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Preoperative Fasting Duration and Medication Instruction: Are We Improving?
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Preoperative Fasting Duration and Medication Instruction: Are We Improving? JEANNETTE T. CRENSHAW, MSN, RN, LCCE, FACCE, IBCLC; ELIZABETH H. WINSLOW, PHD, RN, FAAN
P
atients scheduled for an elective surgery or procedure routinely are told not to eat or drink anything after midnight the night before their procedure (ie, remain NPO after midnight), whether their surgery is scheduled for 7 AM or 2 PM the next day. Rigid fasting regimens, prescribed in an attempt to reduce pulmonary aspiration during anesthesia, have prevailed since the 1940s when Mendelson1 reported a high incidence of pulmonary aspiration during obstetrical anesthesia. Mendelson found 66 instances of pulmonary aspiration in 44,016 (0.15%) women during obstetrical anesthesia at the Lying-In Hospital, New York City, New York, from 1932 to 1945. Two of the patients died. More than half of the patients had received a mixture of gas, oxygen, and ether for anesthesia. Endotracheal intubation during obstetrical anesthesia was rare at the time.2 Mendelson recommended withholding oral feedings during labor and he also suggested emptying the stomach before administering anesthesia (eg, using the “finger in the throat” method). In the 60 years since Mendelson’s report, anesthetic techniques have changed dramatically, and hundreds of studies have been conducted on the effects of fasting on gastric contents. As a result, strict NPO after midnight fasting routines have been challenged.3,4 In 1999, the American Society of Anesthesiologists (ASA) published landmark guidelines that recommend shortening preoperative fasting durations for healthy patients of all ages undergoing elective surgeries and procedures.3 The ASA guidelines are intended for physicians, nurses, and © AORN, Inc, 2008
other health care professionals who care for patients who receive general anesthesia, regional anesthesia, or sedation/ analgesia.3 Although physicians prescribe preoperative fasting durations, nurses have the important responsibilities of instructing patients about preoperative fasting, promoting evidencebased guidelines for fasting, and monitoring patients for compliance and adverse effects.5-7 Nurses need to understand the scientific evidence supporting liberalized fasting practices and what to teach patients. Nurses who are able to publicly state and defend this evidence can be advocates for patients when evidence-based guidelines are not being followed. They also can lead efforts to implement evidence-based changes in fasting practices at their facilities. Unfortunately, many nurses and physicians may not be aware of the
ABSTRACT RESEARCH HAS SHOWN that preoperative fasting practices commonly are much longer than national guidelines, and medication instructions are not always given to patients before surgery. After implementation of an evidence-based preoperative fasting policy and educational efforts for health care providers at one facility, a follow up project was conducted to determine whether these efforts had improved fasting practices. THE PROJECT FINDINGS indicate that preoperative fasting in excess of safe minimum guidelines persists. Improvements were found in the percentage of patients receiving specific instructions about whether to take their routine medications on the morning of surgery. Continued efforts must be made to implement best practices for preoperative fasting. AORN J 88 (December 2008) 963-976. © AORN, Inc, 2008.
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The American Society of Anesthesiologists recommends a minimum fast of two hours for clear liquids and eight hours for a regular meal before surgery.
recommendations to liberalize fasting durations, and if they do know of them, they are not making efforts to change their practices.8 Even when efforts are made to educate health care providers and to implement updated policies and procedures, old habits tend to persist. We studied preoperative fasting practices at an 866-bed, urban, nonprofit hospital in Texas before and after widespread educational efforts about the ASA guidelines.
BACKGROUND This quality improvement (QI) project was a follow-up to a research study we conducted in 2000 and was undertaken to determine whether practices had improved in our facility. The 2000 study5 described how long 155 patients fasted from liquids and solids before undergoing elective procedures, compared these fasting durations to national guidelines,3 and identified the instructions patients were given about taking their routine medications the morning of surgery. We found that, on average, patients were instructed to fast from liquids and solids for nine and 10 hours, respectively.5 These fasting times were longer than those recommended by the ASA, which recommends a minimum fast of two hours for clear liquids and eight hours for a regular meal.3 Nearly two-thirds of the patients (n = 97, 63%) reported that nurses were involved in instructing them about preoperative fasting, and one-third (n = 49, 32%) reported that their only instructions came from a nurse.5 One hundred eighteen patients said
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they took medications regularly. Almost onethird of these patients (n = 38, 32%) reported that they did not receive instructions about whether to take them on the day of surgery. At our institution, surgeons, anesthesia care providers, direct care nurses, and office staff members may give preoperative fasting instructions as prescribed by a physician. We directed our education efforts at all of these groups, although we did not go to surgeons’ offices to talk with their staff members. As a result of our initial research findings, we collaborated with nurses, physicians, and administrators to develop and adopt an evidence-based preoperative fasting policy that addressed clear liquids. The policy was approved by the Medical Board in August 2002. We gave several presentations about this new policy, the ASA guidelines, the scientific evidence on which they are based, and our findings showing the discrepancy between what was being done at our institution and what is recommended. We and others at our facility presented at our nursing council; interprofessional process improvement committee meetings (eg, anesthesiology, surgery); leadership meetings; service line meetings (eg, OR, postanesthesia care unit); the hospital’s research symposium; and the system-wide quality conference. In addition, we presented our research at the Texas Association of Perianesthesia Nurses Conference, September 12, 2003, in Dallas, Texas, which many of our staff members attended. We encouraged questioning of prolonged fasting, which is still common for patients who have afternoon surgery. We also published articles about the new evidence-based preoperative fasting policy, ASA recommendations, and our research findings in our nursing and hospital newsletter and in the system-wide physician newsletter. We developed and circulated a colorful, onepage evidence-based practice flyer on preoperative fasting in collaboration with our nursing research committee. Members of the surgery process improvement committee changed preprinted fasting orders for our day surgery unit to include options other than NPO after midnight, such as “Clear liquids until _________.” We placed the
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“NPO after midnight” option last instead of first on the preprinted order sheet to promote the use of alternative recommendations. Our educational efforts were supported by the widespread media attention that our 2002 fasting publication received. Our research was featured in newspapers, magazines, and radio and television programs nationwide, with titles such as “Presurgical fasts slow to be taken off the menu”9 and “No need to go on empty so long before surgery.”10 Some of our staff members learned of our research through this media attention or through the updates that our health care system’s media department sent out. In fact, intermittent media attention continued beyond the immediate time frame of publication. In the summer of 2006, a reporter wrote a newspaper article about unnecessarily long surgical fasting times after his child was instructed to remain NPO after midnight and surgery was delayed.11 Data collection for the QI project reported here began in June 2004, about two years after the policy was adopted and focused education about liberalizing preoperative fasting was initiated at our facility. The purpose of the QI project was to determine the effects of our educational efforts and policy. All patients included in the present project gave verbal agreement to participate. A semi-final draft of this article was sent to the chair of the hospital’s institutional review board, who confirmed that this project adequately protected the rights and privacy of patients and other persons directly and indirectly involved.
REVIEW
OF THE
LITERATURE
Based on an exhaustive review of the literature and expert opinion, the ASA3 published new fasting guidelines in 1999 for healthy patients of all ages having elective surgery or procedures. These guidelines are not standards or mandates; rather, they are recommendations for best practices developed through rigorous analysis of more than 1,000 studies, sophisticated statistical techniques, and expert consensus. The ASA guidelines are based on studies showing that • pulmonary aspiration is a rare complication in modern anesthesia;
•
there is little relationship between fasting duration and gastric volume and pH; • prolonged fasting does not ensure an empty stomach; and • clear liquids taken two to four hours before surgery may reduce gastric volumes. The guidelines differentiate between clear liquids; breast milk; formula, nonclear liquids, and light solids; and heavy, fatty solids. The guidelines indicate a minimum fast of • two hours from clear liquids (eg, black tea, black coffee, soda, juice without pulp); • four hours from breast milk; • six hours from infant formula, nonhuman milk, and from a light meal (eg, tea and toast); and • eight hours from a regular or heavy meal (eg, fried or fatty foods)3 (Table 1). We call this the “2-4-6-8 guideline.” The fasting guidelines apply to both children and adults; however, the guidelines are not intended for women in labor; for patients with conditions that might affect gastric emptying (eg, obesity, diabetes, gastroesophageal reflux disease [GERD]); or for patients with potential airway management problems. Maltby12 pointed out
TABLE 1
Summary of Preoperative Fasting Recommendations1 Length of fast
Beverage or food
2 hours
Clear liquids
4 hours 6 hours
Breast milk Formula, milk, light meal (eg, tea and toast)
8 hours
Regular meal
For healthy patients of all ages undergoing elective procedures (excluding women in labor). 1. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: Report by the American Society of Anesthesiologists Task Force on Preoperative Fasting. Anesthesiology. 1999;90(3):896-905.
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that the ASA’s recommendation for a twohour minimum fast from clear liquids is not revolutionary, but was what Lister recommended in 1882: While it is desirable that there should be no solid matter in the stomach when chloroform is administered, it will be found very salutary to give a cup of tea or beef-tea about two hours previously.13(p172) PREOPERATIVE FASTING AND ASPIRATION PNEUMONIA. The instruction to remain NPO after midnight is based on the assumption that food or fluid consumed six to eight hours before anesthesia remains in the stomach and increases the risk of aspiration.2 In addition, there is an assumption that by abstaining from food and fluids for six to eight hours, the stomach is more likely to be empty and the chance of aspiration is decreased. Aspiration pneumonia, caused by pulmonary aspiration of gastric contents, can be life-threatening and is one of the most feared anesthetic complications.14-16 Pulmonary aspiration and death resulting from aspiration are rare complications in modern anesthesia17-19 and do not justify rigid preoperative fasting orders for all patients. In a retrospective study of 185,358 surgical patients with and without risk factors for aspiration, Swedish researchers identified 83 aspirations.17 The incidence of x-ray confirmed aspiration pneumonitis was lower (one in 4,521 or 2.2 in 10,000). Four patients died. Aspirations in this
study were more common at night, in sicker patients, and during emergency surgery. Similar results were found in a prospective survey of anesthesia-related morbidity and mortality in 40,240 infants and children who received general and regional anesthesia in 461 randomly selected institutions in France.18 Four patients aspirated; none of them died. The authors noted that two patients whose tracheas were not intubated were categorized as having had pulmonary aspiration, but that they would have been more correctly categorized as having suffered airway mismanagement. In a more recent retrospective study, investigators studied 172,334 healthy patients undergoing 215,488 surgeries with general anesthesia during a six-year period at the Mayo Clinic.19 Pulmonary aspiration occurred in 67 patients. The incidence of aspiration was one in 8,000 for patients with an ASA physical status of I or II (Table 2); none of these aspirations caused serious pulmonary complications or death. These studies demonstrate a dramatic reduction in pulmonary aspiration during anesthesia since Mendelson’s report.1 Mendelson reported an incidence of pulmonary aspiration of 0.15% (66 of 44,016) compared with 0.04% (83 of 185,358) reported by Olsson et al,17 0.01% (4 of 40,240) reported by Tiret et al,18 and 0.04% (67 of 172,334) reported by Warner et al.19 Thus, Mendelson’s 1946 report of pulmonary aspiration during anesthesia is about four to 15 times higher than that reported within the last three decades.
TABLE 2
American Society of Anesthesiologists (ASA) Physical Status Classification System1 Physical status
Definition
I II III IV V VI
A normal healthy patient A patient with mild systemic disease A patient with severe systemic disease A patient with systemic disease that is a constant threat to life A moribund patient who is not expected to survive without the surgery A brain-dead declared patient whose organs are removed for donor purposes
1. ASA Physical Status Classification System. American Society of Anesthesiologists. http://www.asahq.org /clinical/physicalstatus.htm. Accessed October 7, 2008.
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Fortunately, death from pulmonary aspiration during anesthesia is a rare occurrence. Pandit and Pandit2 attribute the current low incidence to better identification of patients at risk for pulmonary aspiration and improvements in anesthetic techniques and medications rather than to the use of traditional fasting guidelines. The traditional fasting practices may subject surgical patients to unduly long fasting periods. FASTING DURATION, GASTRIC VOLUME, AND PH. The ASA guidelines cite numerous well-designed and controlled studies showing little relationship between fasting duration, gastric volume, and pH.3 A few of these studies are summarized here. British researchers randomly assigned 45 nonpregnant women having gynecological surgery to two groups.20 The first group (n = 22) fasted overnight (average fast 12 hours ± 35 minutes) and the second group (n = 23) was given a light breakfast comprising one slice of buttered toast and one cup of tea or coffee with milk the morning of surgery (average fast 4 hours ± 1 hour). Gastric contents were aspirated by gastric tube immediately after induction of anesthesia. To obtain maximum recovery of gastric contents, patients were turned to the right and left lateral position and the headdown position. No significant difference between the fasting and nonfasting groups was found in gastric volume, median pH of stomach contents, or the incidence of gastric pH < 3.0. The authors concluded that prolonged fasting does not guarantee an empty stomach and that a light breakfast four hours before elective gynecological surgery does not alter the gastric volume or pH. In a similar study, 300 elective surgical patients were randomly assigned to one of three groups: those who received 150 mL of black coffee the morning of surgery, those who received 150 mL of orange juice the morning of surgery, or those who fasted overnight.21 The average fast for the coffee and juice groups was two to three hours; the average fast for the overnight group was 12 hours. All participants were considered to be at low risk for anesthesia complications. After induction of anesthesia, residual gastric fluids were suc-
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The traditional fasting instruction of remaining NPO after midnight does not differentiate between clear liquids and other food and beverages even though the rates of gastric emptying vary significantly.
tioned through a nasogastric tube. No significant differences in gastric volume or pH were found among the three groups. Drinking clear liquids a few hours before surgery actually may reduce gastric volumes by stimulating gastric peristalsis and emptying. Investigators randomly assigned women scheduled for a first trimester therapeutic abortion to remain NPO until surgery or to drink 150 mL of water 2.5 hours before surgery.22 Gastric volumes were significantly less in the group of women who drank 150 mL of water compared to the group who fasted (17.6 mL ± 14.5 versus 26.7 ± 18.9 mL). Other research has produced similar findings.4,23,24 TYPE OF LIQUID OR FOOD AND GASTRIC TRANSIT. The traditional fasting instruction of remaining NPO after midnight does not differentiate between clear liquids and other foods and beverages even though the rates of gastric emptying vary significantly. Clear liquids, full liquids, and solids behave differently in the stomach.3 Clear liquids leave the stomach almost immediately after ingestion while solids first must be broken down. Full liquids fall in between. In a 1968 study of gastric emptying, adult participants were given a 750-mL, clear-liquid test meal.25 It took an average of 11 ± 2.2 minutes for half of the gastric contents to empty; an average of 72 ± 13.1 minutes were required for the gastric volume to be reduced to 10 mL. By contrast, many hours are needed for the stomach to empty after solid foods.26,27 Given the difference in gastric transit AORN JOURNAL •
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Studies have shown that preoperative patients fast for prolonged periods of time from both clear liquids and solids and often do not receive instructions about taking routine medications on the morning of surgery.
between clear liquids and solid foods, it is puzzling that patients are told to fast the same amount of time from clear liquids and other liquids and foods. The ASA guidelines3 indicate that the volume of liquid ingested is less important than the type of liquid ingested.
PURPOSES Previous studies have shown that preoperative patients fast for prolonged periods of time from both clear liquids and solids and often do not receive instructions about taking routine medications on the morning of surgery or, if they are hospitalized, may not be given their medications.5,7,28 The purpose of this QI project was to compare preoperative fasting practices at our facility before and after widespread educational efforts and implementation of an evidence-based preoperative fasting policy for clear liquids. For the purposes of this QI project, instructed fasting time was defined as the time between when the patient was told to start fasting and the scheduled surgery time and actual fasting time was defined as the time between the last time the patient ate or drank and the induction of anesthesia. The specific objectives of the QI project were to determine whether there were differences between • instructed liquid and solid fasting times, in hours, for patients in 2000 versus 2004; • actual liquid and solid fasting times, in hours, for patients in 2000 versus 2004; • the percentage of patients scheduled for
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afternoon surgery who were told to remain NPO after midnight in 2000 versus 2004; the percentage of patients who fasted for 12 hours or more in 2000 versus 2004; the percentage of patients who fasted for 15 hours or more in 2000 versus 2004; and the percentage of patients on routine medications given specific instructions about taking their medications the morning of surgery in 2000 versus 2004.
SAMPLE Because we wanted to compare data from our 2000 study with data from the 2004 QI project, we used similar inclusion and exclusion criteria. To be eligible to participate, patients had to • be 18 years of age or older; • speak English; • be admitted to the hospital from home for a nonobstetric, nongastrointestinal procedure; • be in stable condition; • have no IV infusion for more than four hours before surgery; • have been admitted to a noncritical care unit after surgery; and • agree to participate. To be consistent with the hospital’s new preoperative fasting policy for clear liquids, the QI project exclusion criteria included the following: • obesity (ie, body mass index > 30); • diabetes mellitus; • hiatal hernia; • GERD; • gastrointestinal surgery; and • pregnancy. Data collection for the 2004 QI project (N = 275) began on June 7, 2004, and was completed on October 6, 2004. We compared data for the QI project with our previous research study data (N = 155), which were collected between November 12, 1999, and May 18, 2000.5
PROCEDURES For the QI project, 275 postoperative patients were interviewed by 15 nurse data collectors using a structured interview tool. The interview tool used in this QI project was similar to the tool used in two previous studies of preoperative fasting practices.5,7 The original
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interview tool was based on a literature review, our clinical experiences, and recommendations from members of the hospital’s nursing research committee and two anesthesiologists.5 This tool was later slightly revised to increase the specificity of a few questions for a study of preoperative fasting practices in women having scheduled cesarean birth.7 The tool used in the current QI project was a simpler, shorter version of the original tool (ie, 16 questions versus 24). This abbreviated version was designed to focus on fasting durations and medication instructions and to omit questions related to thirst, hunger, and discomfort. Questions about age, gender, type and date of surgery, scheduled and actual time of surgery, and ASA classification were included to describe the population. Patient questions included the following: • What instructions did you receive regarding eating and drinking before your procedure/ surgery? • Do you take medications by mouth daily? • What instructions did you receive about taking your medications on the day of your procedure/surgery? • What time did you have your last liquid/ beverage before your procedure/surgery? • What was this liquid/beverage? • What time did you eat your last solid food before your procedure/surgery? Data were not collected about patients who did not agree to take part in this QI project. Data were collected by more nurses in the QI project than in the previous research study (15 versus nine), and educational efforts about liberalizing preoperative fasting continued during the QI project.
DATA ANALYSIS The data were entered into a spreadsheet. We used the Statistical Package for Social Sciences (SPSS) version 15.029 and Microsoft® Excel 2002 statistical functions for data analysis. Descriptive statistics included frequency counts, percentages, and measures of central tendency and dispersion. Inferential statistics (ie, chi-square and t tests for independent samples) were computed to test for differences between the 2000 and 2004 populations in
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• • • •
age, gender, physical status, instructed and actual fasting durations for liquids and solids, • liquid fasting times greater than 12 hours and greater than 15 hours, • the percentage of patients who were told to remain NPO after midnight, • the percentage of patients scheduled for afternoon surgery who were told to remain NPO after midnight, • the percentage of patients who received instructions for medications on the day of surgery, and • the percentage of patients whose surgery was early. The level of statistical significance was set at P = .05.
RESULTS Results are described in Table 3. Patients in the 2004 QI project averaged 49.5 ± 17 years of age, while patients in the 2000 study averaged 53.5 ± 17 years of age (P = .02). A total of 77% of the patients in 2004 were women compared with 53% in 2000 (P = .00). The percentage of patients categorized with an ASA physical status of I or II was 81% in 2004 compared with 70% in 2000 (P = .01). FASTING DURATIONS—LIQUIDS. Patients were instructed to fast from clear liquids for 9.0 ± 3 hours in 2004 compared with 9.4 ± 2 hours in 2000 (P = .11). The range of time patients were instructed to fast from clear liquids in 2004 was one to 16 hours. The instruction for the patient who had the shortest fast was “clear liquids until 6 AM” for vaginal sling surgery scheduled at 7:15 AM. The longest instructed clear liquid fast was for a patient scheduled for orthopedic surgery at 3:45 PM who was told to remain NPO after midnight. Patients actually fasted from clear liquids for an average of 11 ± 3 hours in 2004 versus 11.9 ± 3 hours in 2000 (P = .005). The percentage of patients fasting from liquids for 12 hours was 40% in 2004 compared with 47% in 2000 (P = .15). The percentage of patients fasting from liquids for 15 hours was 8% in 2004 versus 13% in 2000 (P = .13). FASTING DURATIONS—SOLIDS. Patients were instructed to fast from solids for 9.7 ± 2 hours in AORN JOURNAL •
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TABLE 3
Comparison of 2000 and 2004 Findings of Preoperative Fasting Practices in 430 Patients Variable
2000
2004
Number of surgical patients
155
275
Mean age (standard deviation [SD]; range)
53.5 (± 17; 20-90)
49.5 (± 17; 18-87)
0.02*
Gender: % women
53%
77%
0.00*
70%
81%
0.01*
9.4 (± 2; 4-20)
9.0 (± 3; 1-16)
0.11
11.9 (± 3; 3-20)
11.0 (± 3; 2-21)
0.005*
10.0 (± 3; 7-31)
9.7 (± 2; 6-16)
0.61
14.5 (± 4; 6-37)
14.2 (± 3; 6-24)
0.32
47%
40%
0.15
13%
8%
0.13
91%
85%
0.08
81%
69%
0.19
68%
87%
0.0001*
5%
9%
0.11
American Society of Anesthesiologists physical status: % physical status I or II Mean (SD; range) instructed fasting time for liquids in hours Mean (SD; range) actual fasting time for liquids in hours Mean (SD; range) instructed fasting time for solids in hours Mean (SD; range) actual fasting time for solids in hours % patients fasting from liquids 12 hours: actual % patients fasting from liquids 15 hours: actual % patients instructed to remain NPO after midnight % patients scheduled for afternoon surgery instructed to remain NPO after midnight % patients on routine medications given specific instructions % patients whose surgery was performed early
P value
*P 0.05 (significant difference)
2004 versus 10 ± 3 hours in 2000 (P = .61). Patients actually fasted from solids for an average of 14.2 ± 3 hours in 2004 versus 14.5 ± 4 hours in 2000 (P = .32). NPO INSTRUCTIONS. Most patients received NPO after midnight instructions (85% in 2004 versus 91% in 2000; P = .08). In 2004, 68 patients were scheduled for afternoon surgery. One of these patients reported being given no fasting instructions. Of the 67 remaining patients, 46 (69%) were instructed to remain NPO after midnight. In 2000, 33 patients were scheduled for after-
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noon surgery. One of these patients reported receiving no instructions. Of the 32 remaining patients, 26 (81%) were instructed to remain NPO after midnight. Thus, the percentage of patients scheduled for afternoon surgery who were told to remain NPO after midnight was 69% in 2004 versus 81% in 2000 (P = .19). INSTRUCTIONS ABOUT ROUTINE MEDICATIONS. The percentage of patients on routine medications who were given specific instructions about whether to take the medications was 87% in 2004. The percentage was 68% in 2000 (P = .0001).
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EARLY SURGERIES. Nine percent of the surgeries in 2004 and 5% in 2000 were performed early (ie, more than 20 minutes before the scheduled time of surgery; P = .11). These surgeries averaged 56 minutes early (range 21-166 minutes) in 2004 compared to 33 minutes early (range 25-50 minutes) in 2000.
DISCUSSION Although this QI project had more data collectors, had more participants, and was conducted during a shorter period of time than the original study, and educational efforts continued during the project, the results are similar. The prolonged fasting durations from clear liquids were particularly disappointing. Despite widespread educational efforts about the ASA guidelines and their supporting evidence, and despite the adoption of a preoperative fasting policy for clear liquids, little progress has been made in liberalizing preoperative fasting for liquids at our facility. Fasting times were similar in both 2000 and 2004, and fasting from clear liquids was well in excess of recommended safe fasting durations. Based on our colleagues’ reports, unnecessarily long preoperative fasting times are common in facilities across the country. In fact, this may be a problem worldwide.30 Although the findings from our QI project show trends toward shorter fasting durations from the period between 2000 and 2004 in our facility, the only result that was statistically significant was the actual fasting time for liquids (11 hours in 2004 versus 11.9 in 2000). We do not consider this difference to be a clinically important difference, however. This fasting time is still substantially longer than the ASA recommended minimum fasting time of two hours for clear liquids. The patients in the 2004 QI project were significantly younger than those in the 2000 study, and there were more women and more patients with an ASA physical status of I or II. Differences in age and gender, however, should not influence fasting instructions. Differences in ASA physical status also should not affect fasting instructions,6 as long as patients who are obese; have diabetes mellitus, hiatal hernia, or GERD; are undergoing gastrointestinal sur-
Little progress has been made in liberalizing preoperative fasting for liquids at our facility. The prolonged fasting durations from clear liquids were particularly disappointing.
gery; or have other contraindications are excluded. These patients were excluded in our 2004 QI project. Recently, Maltby and colleagues31 showed that obesity does not affect the volume and pH of gastric contents. Patients continue to be instructed to fast for unnecessarily long times before surgery. Instructions for fasting from clear liquids and solids continue to be similar despite dramatic differences in gastric transit times. These and our other findings show that many caregivers continue to base their fasting instructions on the Mendelson1 tradition rather than on evidencebased guidelines.3 We are most concerned about instructions for fasting from clear liquids, since this is where the largest discrepancy exists between ASA recommendations and practice. The ASA guidelines recommend a minimal fast from clear liquids of two hours; by contrast, patients in our studies were instructed to fast from clear liquids for an average of nine hours. In addition, thirst is more bothersome to patients than hunger.5 Thirst, as well as caffeine headaches for those patients who are caffeine-dependent, can be important dissatisfiers for preoperative patients. Fasting from solids is a lesser concern. The average instructed fasting time for solids (ie, 10 hours) is only two hours more than the eight hours recommended by the ASA for a regular meal. Almost half the patients in our investigations fasted from liquids for 12 hours or more and some fasted from liquids for 15 hours or more. The vast majority of our patients were instructed to remain NPO after midnight. The AORN JOURNAL •
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Almost half of the patients in our investigations fasted from liquids for 12 hours or more, and some fasted from liquids for 15 hours or more; the vast majority of patients were instructed to remain NPO after midnight.
proportion of patients scheduled for afternoon surgery who were told to remain NPO after midnight was lower in 2004 than in 2000 (69% versus 81%) but this difference was not statistically significant (P = .19). Our data show average instructed time of fasting for liquids of nine hours in both 2000 and in 2004. Patients’ actual fasting durations for liquids were 11.9 hours in 2000 and 11 hours in 2004. Patients’ actual fasting durations generally are longer than instructed because of individual sleeping and eating schedules. For example, if a female patient who is instructed to be NPO after midnight for surgery scheduled at 10 AM (ie, instructed fast of 10 hours) has dinner at 6 PM and goes to bed at 10 PM, then she actually has fasted for 16 hours before surgery. If she has a snack before bed, her fasting duration would be 12 hours. If the patient had been told she could have clear liquids until 7 AM, however, this could have reduced her thirst, irritability, symptoms of caffeine withdrawal, and susceptibility to dehydration and hypovolemia. Our major concern is instructed rather than actual fasting durations since physicians and nurses have control over the instructed fasting durations. EARLY SURGERIES. One reason stated by physicians and nurses at our facility and elsewhere for the reluctance to give instructions other than NPO after midnight is the possibility that procedures may be moved to an earlier time
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slot.32,33 This concern can be put to rest by our findings in both 2000 and 2004. Fewer than 10% of the studied procedures were moved to an earlier time slot, and the procedures averaged only 33 minutes early in the 2000 study and 56 minutes early in 2004. If the ASA guidelines for preoperative fasting from clear liquids were followed, no procedures would have been cancelled because of this earlier time slot. As Chapman pointed out,34 physicians and nurses tend to exaggerate the variability in the OR schedule. Other researchers found that permitting clear liquids until three hours before surgery did not affect cancellations or delays.32 MEDICATION INSTRUCTION. The significant improvement in instruction about whether to take medications on the morning of surgery was gratifying; however, 13% of patients on routine medications did not receive instructions. Taking medications that should not be taken (eg, medications that increase the chance of bleeding) or not taking medications that should be taken (eg, asthma medications) can increase the risk of adverse operative and postoperative events. A potential participant in a study of preoperative fasting in women having a scheduled cesarean birth7 did not take her asthma medication because she was told to fast. She had an acute asthma attack and the surgery had to be postponed. This highlights the fact that all patients on routine medications need to receive specific instructions about which medications to take before surgery. WHY NPO AFTER MIDNIGHT PERSISTS. Although scientific data are available, resistance to change is significant. Barriers to implementing evidencebased guidelines are complex and multifactorial and are influenced by political, organizational, financial, cultural, and scientific interests.8 Education alone will not “fix” the problem; rather, multimodal strategies are needed. Physicians and nurses prefer to give all preoperative patients one instruction. It is simpler to tell everyone to remain NPO after midnight than to individualize instructions depending on the time of surgery and other factors; however, patients are perfectly capable of stopping solids by a specified time, differentiating between clear and nonclear liquids, and stopping clear liquids
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by a specified time.6,32 Health care providers’ fear that patients cannot or will not follow instructions other than NPO after midnight is patronizing and unjustified. Based on their self reports, the patients in our investigations were overly compliant, fasting longer than instructed, suggesting patients do not want to jeopardize their surgical outcomes. Other major reasons that the “NPO after midnight” ritual persists include the difficulty in changing entrenched traditions that do not seem to be hurting patients, concerns that more liberalized fasting instructions will prevent surgical procedures from being moved to an earlier time, and exaggerated fears about the risk of pulmonary aspiration.8 Lack of knowledge about the ASA preoperative fasting guidelines, the hundreds of controlled trials demonstrating the safety and efficacy of liberalized preoperative fasting, and the difference in gastric transit of liquids versus solids contributes to the perpetuation of the “NPO after midnight” tradition. Many health care providers still believe the myth that prolonged fasting reduces gastric volumes and are unfamiliar with the studies that show consumption of clear liquids several hours before surgery actually may decrease gastric volumes.4,23 Longer fasting is not better or safer; basing fasting on evidence-based guidelines is better and safer.
IMPLICATIONS
FOR
PRACTICE
Because the “NPO after midnight” tradition is difficult to change and new scientific evidence is not enough to change practice,8,35 nurses, anesthesia care providers, and surgeons must work together to actively implement evidence-based practice. We recommend continuing widespread education about the ASA guidelines and their strong supporting evidence for physicians and nurses in hospitals, day surgery facilities, and physicians’ offices. We suggest focusing on • liberalizing fasting instructions for clear liquids for all patients, • differentiating between clear liquids and solids in fasting instructions, and • targeting the afternoon surgery patients to make sure they are instructed to have clear liquids or a light breakfast the morning of surgery.
Health care providers’ fear that patients cannot or will not follow instructions other than NPO after midnight is patronizing and unjustified.
Afternoon surgery patients have the longest preoperative fasting times and are at the greatest risk for adverse effects of prolonged fasting. In addition, preprinted orders need to be evaluated and options other than NPO after midnight need to be included. It may be necessary to track fasting times on a unit to make it more obvious to caregivers how long patients are fasting, or to have a “model unit” to demonstrate the safety and ease of liberalized fasting in the facility. It also is important to educate consumers about preoperative fasting guidelines. Consumers may be the most important agents for change. Patients scheduled for afternoon surgery need to ask for a light meal and clear liquids; patients who do not ask may go hungry and thirsty. Nurses can make a big difference in preventing unnecessarily long preoperative fasting. Nurses can cite evidence from the ASA guidelines, make recommendations to physicians, and lead the way toward implementing best practices. Nurses can use 2-4-6-8 as a reminder that the minimum fasting guidelines are • two hours for clear liquids, • four hours for breast milk, • six hours for milk or a light meal, and • eight hours for a regular meal. This is safe for healthy patients of all ages undergoing elective procedures who have no contraindications. It is time to base our practice on up-to-date evidence as opposed to evidence from the 1940s. We hope this article will serve as a catalyst for renewed efforts to update outmoded fasting practices, and will encourage individual AORN JOURNAL •
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nurses to act as vocal and knowledgeable advocates for the fasting patient. Acknowledgements: The authors would like to thank Margaret Martin, MSN, RN, BC, CIC, director, patient care resources, Presbyterian Hospital of Dallas, Texas, and David Eubanks, MSN, RN, former administrative director clinical learning academic partnerships, Arlington, TX, for administrative support; Richard Gilder, BSN, RN, former clinical consultant/outcomes analyst, Texas Health Resources, Arlington, TX, for statistical analysis assistance; the nurses who helped with data collection, the Nursing Research Committee, and the patients who participated; and Cathy Y. Nakashima, MLS, MBA, and Jeanette Prasifka, MLS, medical librarians, Presbyterian Hospital of Dallas, for library services. We also thank Joy Don Baker, PhD, RN-BC, CNE, CNOR, NEA-BC, associate clinical professor and director, distance education, University of Texas at Arlington, and Kathy A. Baker, PhD, RN, ACNS-BC, CGRN, associate professor, director, doctor of nursing practice program, Texas Christian University, Fort Worth, Texas, for their thoughtful reviews of an earlier version of this article. Editor’s note: Excel is a registered trademark of Microsoft Corp, Redmond, WA.
REFERENCES 1. Mendelson CL. The aspiration of stomach contents into the lungs during obstetric anesthesia. Amer J Obstet Gynecol. 1946;52:191-205. 2. Pandit UA, Pandit SK. Fasting before and after ambulatory surgery. J Perianesth Nurs. 1997;12(3): 181-187. 3. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: a report by the American Society of Anesthesiologist Task Force on Preoperative Fasting. Anesthesiology. 1999; 90(3):896-905. 4. Agarwal A, Chari P, Singh H. Fluid deprivation before operation. The effect of a small drink. Anaesthesia. 1989;44(8):632-634. 5. Crenshaw JT, Winslow EH. Preoperative fasting: old habits die hard. Am J Nurs. 2002;102(5):36-45. 6. Winslow EH, Crenshaw JT, Warner MA. Best practices shouldn’t be optional: prolonged fasts aren’t more effective—or even safer. Am J Nurs. 2002;102(6):59, 63. 7. Crenshaw JT, Winslow EH. Actual versus in-
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structed fasting times and associated discomforts in women having scheduled cesarean birth. J Obstet Gynecol Neonatal Nurs. 2006;35(2):257-264. 8. Bosse G, Breuer JP, Spies C. The resistance to changing guidelines—what are the challenges and how to meet them. Best Pract Res Clin Anaesthesiol. 2006;20(3):379-395. 9. Davis R. Pre-surgical fasting slow to be taken off the menu. USA Today. May 7, 2002. 10. Lange DP. No need to go on empty so long before surgery. Los Angeles Times. May 13, 2002:S2. 11. Kohn D. Slow demise for long preoperative fasts; doctors ban food, drink for hours before surgery, though the practice has little benefit. The Baltimore Sun. July 23, 2006:1A. 12. Maltby JR. Fasting from midnight—the history behind the dogma. Best Pract Res Clin Anaesthesiol. 2006;20(3):363-378. 13. Lister JL. The Collected Papers of Joseph Baron Lister. Vol 1. Special ed. Birmingham, AL: Classics of Medicine Library; 1979:172. 14. Brown DL, Heard SO, Stevens DS, Kirby RR. Preoperative evaluation of high-risk surgical patients. In: Civetta JM, Taylor RW, Kirby RR, eds. Critical Care. 3rd ed. Philadelphia: LippincottRaven; 1997:999-1007. 15. Mecca RS. Postoperative recovery. In: Barash PG, Cullen BF, Stoelting RK, eds. Clinical Anesthesia. Philadelphia, PA: Lippincott Williams & Wilkins; 1989:1516. 16. Schreiner MS. Preoperative and postoperative fasting in children. Pediatr Clin North Am. 1994; 41(1):111-120. 17. Olsson GL, Hallen B, Hambraeus-Jonzon K. Aspiration during anaesthesia: a computer-aided study of 185,358 anaesthetics. Acta Anaesthesiol Scand. 1986;30(1):84-92. 18. Tiret L, Nivoche Y, Hatton F, Desmonts JM, Vourc’h G. Complications related to anaesthesia in infants and children. A prospective survey of 40240 anaesthetics. Br J Anaesth. 1988;61(3):263-269. 19. Warner MA, Warner ME, Weber JG. Clinical significance of pulmonary aspiration during the perioperative period. Anesthesiology. 1993;78(1):56-62. 20. Miller M, Wishart HY, Nimmo WS. Gastric contents at induction of anaesthesia. Is a 4-hour fast necessary? Br J Anaesth. 1983;55(12):1185-1188. 21. Hutchinson A, Maltby JR, Reid CR. Gastric fluid volume and pH in elective inpatients. Part I: coffee or orange juice versus overnight fast. Can J Anaesth. 1988;35(1):12-15. 22. Maltby JR, Sutherland AD, Sale JP, Shaffer EA. Preoperative oral fluids: is a five-hour fast justified prior to elective surgery? Anesth Analg. 1986;65: 1112-1116. 23. Maltby JR, Koehli N, Ewen A, Shaffer EA. Gastric fluid volume, pH, and emptying in elective inpatients. Influences of narcotic-atropine premedication, oral fluid, and ranitidine. Can J Anaesth. 1988;35(6):562-566. AORN JOURNAL •
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24. Sutherland AD, Maltby JR, Sale JP, Reid CR. The effect of preoperative oral fluid and ranitidine on gastric fluid volume and pH. Can J Anaesth. 1987; 34(2):117-121. 25. George JD. New clinical method for measuring the rate of gastric emptying: the double sampling test meal. Gut. 1968;9(2):237-242. 26. Maltby JR. New guidelines for preoperative fasting. Can J Anaesth. 1993;40(5 Pt 2):R113-R121. 27. Minami H, McCallum RW. The physiology and pathophysiology of gastric emptying in humans. Gastroenterology. 1984;86(6):1592-1610. 28. Pearse R, Rajakulendran Y. Pre-operative fasting and administration of regular medications in adult patients presenting for elective surgery. Has the new evidence changed practice? Eur J Anaesthesiol. 1999;16(8):565-568. 29. Statistical Package for Social Sciences, version 15.0. Chicago, IL: SPSS; 2006. 30. Shime N, Ono A, Chihara E, Tanaka Y. Current practice of preoperative fasting: a nationwide survey in Japanese anesthesia-teaching hospitals. J Anesth. 2005;19(3):187-192. 31. Maltby JR, Pytka S, Watson NC, Cowan RA, Fick GH. Drinking 300 mL of clear fluid two hours before surgery has no effect on gastric fluid volume and pH in fasting and non-fasting obese patients. Can J Anaesth. 2004;51(2):111-115. 32. Murphy GS, Ault ML, Wong HY, Szokol JW.
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The effect of a new NPO policy on operating room utilization. J Clin Anesth. 2000;12(1):48-51. 33. Doswell WM, Jones MA, O’Donnell JM. One size may not fit all: it's not always possible—or appropriate—to use the ASA guidelines for preoperative fasting. Am J Nurs. 2002;102(6):58, 61. 34. Chapman A. Current theory and practice: a study of pre-operative fasting. Nurs Stand. 1996; 10(18):33-36. 35. Søreide E, Ljungqvist O. Modern preoperative fasting guidelines: a summary of the present recommendations and remaining questions. Best Pract Res Clin Anaesthesiol. 2006;20(3):483-491.
Jeannette T. Crenshaw, MSN, RN, LCCE, FACCE, IBCLC, is a clinical education specialist at Texas Health Resources, the Center for Learning, Arlington, TX, and graduate faculty for the Nursing Administration Program at the University of Texas at Arlington School of Nursing. Elizabeth H. Winslow, PhD, RN, FAAN, is the research consultant at Presbyterian Hospital of Dallas, Texas.
Electronic Health Records Improve Quality of Care
P
hysicians who use outpatient electronic health records (EHRs) believe they improve quality of care, and usage has increased in the past year, according to an article in the July 3, 2008, issue of The New England Journal of Medicine. Researchers included 2,758 physicians in their national survey, which garnered a 62% response rate between September 2007 and March 2008. For the analysis, researchers differentiated between fully functional and basic systems. Fully functional systems were defined as those that could • record clinical and demographic data; • view and manage laboratory test results and imaging; • manage order entry (eg, electronic prescriptions); and • support clinical decisions (eg, medication interactions or contraindications). Basic systems, by comparison, did not have orderentry capabilities or clinical-decision support. Survey results showed 4% of physicians used fully functional EHRs and 13% used a basic system. Seventy-one percent of physicians using fully func-
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tional systems integrated it with an electronic system at the hospital where they admitted patients, compared to 56% of basic system users. Those using either type of EHR generally were satisfied overall (ie, 93% for fully functional versus 88% for basic) and were satisfied with system reliability (ie, 90% for fully functional versus 79% for basic). Those who were most likely to use EHRs were • primary care physicians, • physicians practicing in large groups, and • hospitals or medical centers. Physicians in the western United States and younger physicians were also more likely to have incorporated EHRs into their practices. Of the 83% of respondents not using an EHRs, 16% had purchased but not yet incorporated a system and 26% stated their intent to purchase one within two years. The most common reason for not using an EHR was the cost. DesRoches CM, Campbell EG, Rao SR et al. Electronic health records in ambulatory care—a national survey of physicians. N Engl J Med. 2008;359(1):50-60.
Preoperative Fasting Duration and Medication Instruction: Are We Improving? JEANNETTE T. CRENSHAW, MSN, RN, LCCE, FACCE, IBCLC; ELIZABETH H. WINSLOW, PHD, RN, FAAN
P
atients scheduled for an elective surgery or procedure routinely are told not to eat or drink anything after midnight the night before their procedure (ie, remain NPO after midnight), whether their surgery is scheduled for 7 AM or 2 PM the next day. Rigid fasting regimens, prescribed in an attempt to reduce pulmonary aspiration during anesthesia, have prevailed since the 1940s when Mendelson1 reported a high incidence of pulmonary aspiration during obstetrical anesthesia. Mendelson found 66 instances of pulmonary aspiration in 44,016 (0.15%) women during obstetrical anesthesia at the Lying-In Hospital, New York City, New York, from 1932 to 1945. Two of the patients died. More than half of the patients had received a mixture of gas, oxygen, and ether for anesthesia. Endotracheal intubation during obstetrical anesthesia was rare at the time.2 Mendelson recommended withholding oral feedings during labor and he also suggested emptying the stomach before administering anesthesia (eg, using the “finger in the throat” method). In the 60 years since Mendelson’s report, anesthetic techniques have changed dramatically, and hundreds of studies have been conducted on the effects of fasting on gastric contents. As a result, strict NPO after midnight fasting routines have been challenged.3,4 In 1999, the American Society of Anesthesiologists (ASA) published landmark guidelines that recommend shortening preoperative fasting durations for healthy patients of all ages undergoing elective surgeries and procedures.3 The ASA guidelines are intended for physicians, nurses, and © AORN, Inc, 2008
other health care professionals who care for patients who receive general anesthesia, regional anesthesia, or sedation/ analgesia.3 Although physicians prescribe preoperative fasting durations, nurses have the important responsibilities of instructing patients about preoperative fasting, promoting evidencebased guidelines for fasting, and monitoring patients for compliance and adverse effects.5-7 Nurses need to understand the scientific evidence supporting liberalized fasting practices and what to teach patients. Nurses who are able to publicly state and defend this evidence can be advocates for patients when evidence-based guidelines are not being followed. They also can lead efforts to implement evidence-based changes in fasting practices at their facilities. Unfortunately, many nurses and physicians may not be aware of the
ABSTRACT RESEARCH HAS SHOWN that preoperative fasting practices commonly are much longer than national guidelines, and medication instructions are not always given to patients before surgery. After implementation of an evidence-based preoperative fasting policy and educational efforts for health care providers at one facility, a follow up project was conducted to determine whether these efforts had improved fasting practices. THE PROJECT FINDINGS indicate that preoperative fasting in excess of safe minimum guidelines persists. Improvements were found in the percentage of patients receiving specific instructions about whether to take their routine medications on the morning of surgery. Continued efforts must be made to implement best practices for preoperative fasting. AORN J 88 (December 2008) 963-976. © AORN, Inc, 2008.
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The American Society of Anesthesiologists recommends a minimum fast of two hours for clear liquids and eight hours for a regular meal before surgery.
recommendations to liberalize fasting durations, and if they do know of them, they are not making efforts to change their practices.8 Even when efforts are made to educate health care providers and to implement updated policies and procedures, old habits tend to persist. We studied preoperative fasting practices at an 866-bed, urban, nonprofit hospital in Texas before and after widespread educational efforts about the ASA guidelines.
BACKGROUND This quality improvement (QI) project was a follow-up to a research study we conducted in 2000 and was undertaken to determine whether practices had improved in our facility. The 2000 study5 described how long 155 patients fasted from liquids and solids before undergoing elective procedures, compared these fasting durations to national guidelines,3 and identified the instructions patients were given about taking their routine medications the morning of surgery. We found that, on average, patients were instructed to fast from liquids and solids for nine and 10 hours, respectively.5 These fasting times were longer than those recommended by the ASA, which recommends a minimum fast of two hours for clear liquids and eight hours for a regular meal.3 Nearly two-thirds of the patients (n = 97, 63%) reported that nurses were involved in instructing them about preoperative fasting, and one-third (n = 49, 32%) reported that their only instructions came from a nurse.5 One hundred eighteen patients said
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they took medications regularly. Almost onethird of these patients (n = 38, 32%) reported that they did not receive instructions about whether to take them on the day of surgery. At our institution, surgeons, anesthesia care providers, direct care nurses, and office staff members may give preoperative fasting instructions as prescribed by a physician. We directed our education efforts at all of these groups, although we did not go to surgeons’ offices to talk with their staff members. As a result of our initial research findings, we collaborated with nurses, physicians, and administrators to develop and adopt an evidence-based preoperative fasting policy that addressed clear liquids. The policy was approved by the Medical Board in August 2002. We gave several presentations about this new policy, the ASA guidelines, the scientific evidence on which they are based, and our findings showing the discrepancy between what was being done at our institution and what is recommended. We and others at our facility presented at our nursing council; interprofessional process improvement committee meetings (eg, anesthesiology, surgery); leadership meetings; service line meetings (eg, OR, postanesthesia care unit); the hospital’s research symposium; and the system-wide quality conference. In addition, we presented our research at the Texas Association of Perianesthesia Nurses Conference, September 12, 2003, in Dallas, Texas, which many of our staff members attended. We encouraged questioning of prolonged fasting, which is still common for patients who have afternoon surgery. We also published articles about the new evidence-based preoperative fasting policy, ASA recommendations, and our research findings in our nursing and hospital newsletter and in the system-wide physician newsletter. We developed and circulated a colorful, onepage evidence-based practice flyer on preoperative fasting in collaboration with our nursing research committee. Members of the surgery process improvement committee changed preprinted fasting orders for our day surgery unit to include options other than NPO after midnight, such as “Clear liquids until _________.” We placed the
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“NPO after midnight” option last instead of first on the preprinted order sheet to promote the use of alternative recommendations. Our educational efforts were supported by the widespread media attention that our 2002 fasting publication received. Our research was featured in newspapers, magazines, and radio and television programs nationwide, with titles such as “Presurgical fasts slow to be taken off the menu”9 and “No need to go on empty so long before surgery.”10 Some of our staff members learned of our research through this media attention or through the updates that our health care system’s media department sent out. In fact, intermittent media attention continued beyond the immediate time frame of publication. In the summer of 2006, a reporter wrote a newspaper article about unnecessarily long surgical fasting times after his child was instructed to remain NPO after midnight and surgery was delayed.11 Data collection for the QI project reported here began in June 2004, about two years after the policy was adopted and focused education about liberalizing preoperative fasting was initiated at our facility. The purpose of the QI project was to determine the effects of our educational efforts and policy. All patients included in the present project gave verbal agreement to participate. A semi-final draft of this article was sent to the chair of the hospital’s institutional review board, who confirmed that this project adequately protected the rights and privacy of patients and other persons directly and indirectly involved.
REVIEW
OF THE
LITERATURE
Based on an exhaustive review of the literature and expert opinion, the ASA3 published new fasting guidelines in 1999 for healthy patients of all ages having elective surgery or procedures. These guidelines are not standards or mandates; rather, they are recommendations for best practices developed through rigorous analysis of more than 1,000 studies, sophisticated statistical techniques, and expert consensus. The ASA guidelines are based on studies showing that • pulmonary aspiration is a rare complication in modern anesthesia;
•
there is little relationship between fasting duration and gastric volume and pH; • prolonged fasting does not ensure an empty stomach; and • clear liquids taken two to four hours before surgery may reduce gastric volumes. The guidelines differentiate between clear liquids; breast milk; formula, nonclear liquids, and light solids; and heavy, fatty solids. The guidelines indicate a minimum fast of • two hours from clear liquids (eg, black tea, black coffee, soda, juice without pulp); • four hours from breast milk; • six hours from infant formula, nonhuman milk, and from a light meal (eg, tea and toast); and • eight hours from a regular or heavy meal (eg, fried or fatty foods)3 (Table 1). We call this the “2-4-6-8 guideline.” The fasting guidelines apply to both children and adults; however, the guidelines are not intended for women in labor; for patients with conditions that might affect gastric emptying (eg, obesity, diabetes, gastroesophageal reflux disease [GERD]); or for patients with potential airway management problems. Maltby12 pointed out
TABLE 1
Summary of Preoperative Fasting Recommendations1 Length of fast
Beverage or food
2 hours
Clear liquids
4 hours 6 hours
Breast milk Formula, milk, light meal (eg, tea and toast)
8 hours
Regular meal
For healthy patients of all ages undergoing elective procedures (excluding women in labor). 1. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: Report by the American Society of Anesthesiologists Task Force on Preoperative Fasting. Anesthesiology. 1999;90(3):896-905.
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that the ASA’s recommendation for a twohour minimum fast from clear liquids is not revolutionary, but was what Lister recommended in 1882: While it is desirable that there should be no solid matter in the stomach when chloroform is administered, it will be found very salutary to give a cup of tea or beef-tea about two hours previously.13(p172) PREOPERATIVE FASTING AND ASPIRATION PNEUMONIA. The instruction to remain NPO after midnight is based on the assumption that food or fluid consumed six to eight hours before anesthesia remains in the stomach and increases the risk of aspiration.2 In addition, there is an assumption that by abstaining from food and fluids for six to eight hours, the stomach is more likely to be empty and the chance of aspiration is decreased. Aspiration pneumonia, caused by pulmonary aspiration of gastric contents, can be life-threatening and is one of the most feared anesthetic complications.14-16 Pulmonary aspiration and death resulting from aspiration are rare complications in modern anesthesia17-19 and do not justify rigid preoperative fasting orders for all patients. In a retrospective study of 185,358 surgical patients with and without risk factors for aspiration, Swedish researchers identified 83 aspirations.17 The incidence of x-ray confirmed aspiration pneumonitis was lower (one in 4,521 or 2.2 in 10,000). Four patients died. Aspirations in this
study were more common at night, in sicker patients, and during emergency surgery. Similar results were found in a prospective survey of anesthesia-related morbidity and mortality in 40,240 infants and children who received general and regional anesthesia in 461 randomly selected institutions in France.18 Four patients aspirated; none of them died. The authors noted that two patients whose tracheas were not intubated were categorized as having had pulmonary aspiration, but that they would have been more correctly categorized as having suffered airway mismanagement. In a more recent retrospective study, investigators studied 172,334 healthy patients undergoing 215,488 surgeries with general anesthesia during a six-year period at the Mayo Clinic.19 Pulmonary aspiration occurred in 67 patients. The incidence of aspiration was one in 8,000 for patients with an ASA physical status of I or II (Table 2); none of these aspirations caused serious pulmonary complications or death. These studies demonstrate a dramatic reduction in pulmonary aspiration during anesthesia since Mendelson’s report.1 Mendelson reported an incidence of pulmonary aspiration of 0.15% (66 of 44,016) compared with 0.04% (83 of 185,358) reported by Olsson et al,17 0.01% (4 of 40,240) reported by Tiret et al,18 and 0.04% (67 of 172,334) reported by Warner et al.19 Thus, Mendelson’s 1946 report of pulmonary aspiration during anesthesia is about four to 15 times higher than that reported within the last three decades.
TABLE 2
American Society of Anesthesiologists (ASA) Physical Status Classification System1 Physical status
Definition
I II III IV V VI
A normal healthy patient A patient with mild systemic disease A patient with severe systemic disease A patient with systemic disease that is a constant threat to life A moribund patient who is not expected to survive without the surgery A brain-dead declared patient whose organs are removed for donor purposes
1. ASA Physical Status Classification System. American Society of Anesthesiologists. http://www.asahq.org /clinical/physicalstatus.htm. Accessed October 7, 2008.
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Fortunately, death from pulmonary aspiration during anesthesia is a rare occurrence. Pandit and Pandit2 attribute the current low incidence to better identification of patients at risk for pulmonary aspiration and improvements in anesthetic techniques and medications rather than to the use of traditional fasting guidelines. The traditional fasting practices may subject surgical patients to unduly long fasting periods. FASTING DURATION, GASTRIC VOLUME, AND PH. The ASA guidelines cite numerous well-designed and controlled studies showing little relationship between fasting duration, gastric volume, and pH.3 A few of these studies are summarized here. British researchers randomly assigned 45 nonpregnant women having gynecological surgery to two groups.20 The first group (n = 22) fasted overnight (average fast 12 hours ± 35 minutes) and the second group (n = 23) was given a light breakfast comprising one slice of buttered toast and one cup of tea or coffee with milk the morning of surgery (average fast 4 hours ± 1 hour). Gastric contents were aspirated by gastric tube immediately after induction of anesthesia. To obtain maximum recovery of gastric contents, patients were turned to the right and left lateral position and the headdown position. No significant difference between the fasting and nonfasting groups was found in gastric volume, median pH of stomach contents, or the incidence of gastric pH < 3.0. The authors concluded that prolonged fasting does not guarantee an empty stomach and that a light breakfast four hours before elective gynecological surgery does not alter the gastric volume or pH. In a similar study, 300 elective surgical patients were randomly assigned to one of three groups: those who received 150 mL of black coffee the morning of surgery, those who received 150 mL of orange juice the morning of surgery, or those who fasted overnight.21 The average fast for the coffee and juice groups was two to three hours; the average fast for the overnight group was 12 hours. All participants were considered to be at low risk for anesthesia complications. After induction of anesthesia, residual gastric fluids were suc-
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The traditional fasting instruction of remaining NPO after midnight does not differentiate between clear liquids and other food and beverages even though the rates of gastric emptying vary significantly.
tioned through a nasogastric tube. No significant differences in gastric volume or pH were found among the three groups. Drinking clear liquids a few hours before surgery actually may reduce gastric volumes by stimulating gastric peristalsis and emptying. Investigators randomly assigned women scheduled for a first trimester therapeutic abortion to remain NPO until surgery or to drink 150 mL of water 2.5 hours before surgery.22 Gastric volumes were significantly less in the group of women who drank 150 mL of water compared to the group who fasted (17.6 mL ± 14.5 versus 26.7 ± 18.9 mL). Other research has produced similar findings.4,23,24 TYPE OF LIQUID OR FOOD AND GASTRIC TRANSIT. The traditional fasting instruction of remaining NPO after midnight does not differentiate between clear liquids and other foods and beverages even though the rates of gastric emptying vary significantly. Clear liquids, full liquids, and solids behave differently in the stomach.3 Clear liquids leave the stomach almost immediately after ingestion while solids first must be broken down. Full liquids fall in between. In a 1968 study of gastric emptying, adult participants were given a 750-mL, clear-liquid test meal.25 It took an average of 11 ± 2.2 minutes for half of the gastric contents to empty; an average of 72 ± 13.1 minutes were required for the gastric volume to be reduced to 10 mL. By contrast, many hours are needed for the stomach to empty after solid foods.26,27 Given the difference in gastric transit AORN JOURNAL •
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Studies have shown that preoperative patients fast for prolonged periods of time from both clear liquids and solids and often do not receive instructions about taking routine medications on the morning of surgery.
between clear liquids and solid foods, it is puzzling that patients are told to fast the same amount of time from clear liquids and other liquids and foods. The ASA guidelines3 indicate that the volume of liquid ingested is less important than the type of liquid ingested.
PURPOSES Previous studies have shown that preoperative patients fast for prolonged periods of time from both clear liquids and solids and often do not receive instructions about taking routine medications on the morning of surgery or, if they are hospitalized, may not be given their medications.5,7,28 The purpose of this QI project was to compare preoperative fasting practices at our facility before and after widespread educational efforts and implementation of an evidence-based preoperative fasting policy for clear liquids. For the purposes of this QI project, instructed fasting time was defined as the time between when the patient was told to start fasting and the scheduled surgery time and actual fasting time was defined as the time between the last time the patient ate or drank and the induction of anesthesia. The specific objectives of the QI project were to determine whether there were differences between • instructed liquid and solid fasting times, in hours, for patients in 2000 versus 2004; • actual liquid and solid fasting times, in hours, for patients in 2000 versus 2004; • the percentage of patients scheduled for
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afternoon surgery who were told to remain NPO after midnight in 2000 versus 2004; the percentage of patients who fasted for 12 hours or more in 2000 versus 2004; the percentage of patients who fasted for 15 hours or more in 2000 versus 2004; and the percentage of patients on routine medications given specific instructions about taking their medications the morning of surgery in 2000 versus 2004.
SAMPLE Because we wanted to compare data from our 2000 study with data from the 2004 QI project, we used similar inclusion and exclusion criteria. To be eligible to participate, patients had to • be 18 years of age or older; • speak English; • be admitted to the hospital from home for a nonobstetric, nongastrointestinal procedure; • be in stable condition; • have no IV infusion for more than four hours before surgery; • have been admitted to a noncritical care unit after surgery; and • agree to participate. To be consistent with the hospital’s new preoperative fasting policy for clear liquids, the QI project exclusion criteria included the following: • obesity (ie, body mass index > 30); • diabetes mellitus; • hiatal hernia; • GERD; • gastrointestinal surgery; and • pregnancy. Data collection for the 2004 QI project (N = 275) began on June 7, 2004, and was completed on October 6, 2004. We compared data for the QI project with our previous research study data (N = 155), which were collected between November 12, 1999, and May 18, 2000.5
PROCEDURES For the QI project, 275 postoperative patients were interviewed by 15 nurse data collectors using a structured interview tool. The interview tool used in this QI project was similar to the tool used in two previous studies of preoperative fasting practices.5,7 The original
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interview tool was based on a literature review, our clinical experiences, and recommendations from members of the hospital’s nursing research committee and two anesthesiologists.5 This tool was later slightly revised to increase the specificity of a few questions for a study of preoperative fasting practices in women having scheduled cesarean birth.7 The tool used in the current QI project was a simpler, shorter version of the original tool (ie, 16 questions versus 24). This abbreviated version was designed to focus on fasting durations and medication instructions and to omit questions related to thirst, hunger, and discomfort. Questions about age, gender, type and date of surgery, scheduled and actual time of surgery, and ASA classification were included to describe the population. Patient questions included the following: • What instructions did you receive regarding eating and drinking before your procedure/ surgery? • Do you take medications by mouth daily? • What instructions did you receive about taking your medications on the day of your procedure/surgery? • What time did you have your last liquid/ beverage before your procedure/surgery? • What was this liquid/beverage? • What time did you eat your last solid food before your procedure/surgery? Data were not collected about patients who did not agree to take part in this QI project. Data were collected by more nurses in the QI project than in the previous research study (15 versus nine), and educational efforts about liberalizing preoperative fasting continued during the QI project.
DATA ANALYSIS The data were entered into a spreadsheet. We used the Statistical Package for Social Sciences (SPSS) version 15.029 and Microsoft® Excel 2002 statistical functions for data analysis. Descriptive statistics included frequency counts, percentages, and measures of central tendency and dispersion. Inferential statistics (ie, chi-square and t tests for independent samples) were computed to test for differences between the 2000 and 2004 populations in
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• • • •
age, gender, physical status, instructed and actual fasting durations for liquids and solids, • liquid fasting times greater than 12 hours and greater than 15 hours, • the percentage of patients who were told to remain NPO after midnight, • the percentage of patients scheduled for afternoon surgery who were told to remain NPO after midnight, • the percentage of patients who received instructions for medications on the day of surgery, and • the percentage of patients whose surgery was early. The level of statistical significance was set at P = .05.
RESULTS Results are described in Table 3. Patients in the 2004 QI project averaged 49.5 ± 17 years of age, while patients in the 2000 study averaged 53.5 ± 17 years of age (P = .02). A total of 77% of the patients in 2004 were women compared with 53% in 2000 (P = .00). The percentage of patients categorized with an ASA physical status of I or II was 81% in 2004 compared with 70% in 2000 (P = .01). FASTING DURATIONS—LIQUIDS. Patients were instructed to fast from clear liquids for 9.0 ± 3 hours in 2004 compared with 9.4 ± 2 hours in 2000 (P = .11). The range of time patients were instructed to fast from clear liquids in 2004 was one to 16 hours. The instruction for the patient who had the shortest fast was “clear liquids until 6 AM” for vaginal sling surgery scheduled at 7:15 AM. The longest instructed clear liquid fast was for a patient scheduled for orthopedic surgery at 3:45 PM who was told to remain NPO after midnight. Patients actually fasted from clear liquids for an average of 11 ± 3 hours in 2004 versus 11.9 ± 3 hours in 2000 (P = .005). The percentage of patients fasting from liquids for 12 hours was 40% in 2004 compared with 47% in 2000 (P = .15). The percentage of patients fasting from liquids for 15 hours was 8% in 2004 versus 13% in 2000 (P = .13). FASTING DURATIONS—SOLIDS. Patients were instructed to fast from solids for 9.7 ± 2 hours in AORN JOURNAL •
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TABLE 3
Comparison of 2000 and 2004 Findings of Preoperative Fasting Practices in 430 Patients Variable
2000
2004
Number of surgical patients
155
275
Mean age (standard deviation [SD]; range)
53.5 (± 17; 20-90)
49.5 (± 17; 18-87)
0.02*
Gender: % women
53%
77%
0.00*
70%
81%
0.01*
9.4 (± 2; 4-20)
9.0 (± 3; 1-16)
0.11
11.9 (± 3; 3-20)
11.0 (± 3; 2-21)
0.005*
10.0 (± 3; 7-31)
9.7 (± 2; 6-16)
0.61
14.5 (± 4; 6-37)
14.2 (± 3; 6-24)
0.32
47%
40%
0.15
13%
8%
0.13
91%
85%
0.08
81%
69%
0.19
68%
87%
0.0001*
5%
9%
0.11
American Society of Anesthesiologists physical status: % physical status I or II Mean (SD; range) instructed fasting time for liquids in hours Mean (SD; range) actual fasting time for liquids in hours Mean (SD; range) instructed fasting time for solids in hours Mean (SD; range) actual fasting time for solids in hours % patients fasting from liquids 12 hours: actual % patients fasting from liquids 15 hours: actual % patients instructed to remain NPO after midnight % patients scheduled for afternoon surgery instructed to remain NPO after midnight % patients on routine medications given specific instructions % patients whose surgery was performed early
P value
*P 0.05 (significant difference)
2004 versus 10 ± 3 hours in 2000 (P = .61). Patients actually fasted from solids for an average of 14.2 ± 3 hours in 2004 versus 14.5 ± 4 hours in 2000 (P = .32). NPO INSTRUCTIONS. Most patients received NPO after midnight instructions (85% in 2004 versus 91% in 2000; P = .08). In 2004, 68 patients were scheduled for afternoon surgery. One of these patients reported being given no fasting instructions. Of the 67 remaining patients, 46 (69%) were instructed to remain NPO after midnight. In 2000, 33 patients were scheduled for after-
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noon surgery. One of these patients reported receiving no instructions. Of the 32 remaining patients, 26 (81%) were instructed to remain NPO after midnight. Thus, the percentage of patients scheduled for afternoon surgery who were told to remain NPO after midnight was 69% in 2004 versus 81% in 2000 (P = .19). INSTRUCTIONS ABOUT ROUTINE MEDICATIONS. The percentage of patients on routine medications who were given specific instructions about whether to take the medications was 87% in 2004. The percentage was 68% in 2000 (P = .0001).
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EARLY SURGERIES. Nine percent of the surgeries in 2004 and 5% in 2000 were performed early (ie, more than 20 minutes before the scheduled time of surgery; P = .11). These surgeries averaged 56 minutes early (range 21-166 minutes) in 2004 compared to 33 minutes early (range 25-50 minutes) in 2000.
DISCUSSION Although this QI project had more data collectors, had more participants, and was conducted during a shorter period of time than the original study, and educational efforts continued during the project, the results are similar. The prolonged fasting durations from clear liquids were particularly disappointing. Despite widespread educational efforts about the ASA guidelines and their supporting evidence, and despite the adoption of a preoperative fasting policy for clear liquids, little progress has been made in liberalizing preoperative fasting for liquids at our facility. Fasting times were similar in both 2000 and 2004, and fasting from clear liquids was well in excess of recommended safe fasting durations. Based on our colleagues’ reports, unnecessarily long preoperative fasting times are common in facilities across the country. In fact, this may be a problem worldwide.30 Although the findings from our QI project show trends toward shorter fasting durations from the period between 2000 and 2004 in our facility, the only result that was statistically significant was the actual fasting time for liquids (11 hours in 2004 versus 11.9 in 2000). We do not consider this difference to be a clinically important difference, however. This fasting time is still substantially longer than the ASA recommended minimum fasting time of two hours for clear liquids. The patients in the 2004 QI project were significantly younger than those in the 2000 study, and there were more women and more patients with an ASA physical status of I or II. Differences in age and gender, however, should not influence fasting instructions. Differences in ASA physical status also should not affect fasting instructions,6 as long as patients who are obese; have diabetes mellitus, hiatal hernia, or GERD; are undergoing gastrointestinal sur-
Little progress has been made in liberalizing preoperative fasting for liquids at our facility. The prolonged fasting durations from clear liquids were particularly disappointing.
gery; or have other contraindications are excluded. These patients were excluded in our 2004 QI project. Recently, Maltby and colleagues31 showed that obesity does not affect the volume and pH of gastric contents. Patients continue to be instructed to fast for unnecessarily long times before surgery. Instructions for fasting from clear liquids and solids continue to be similar despite dramatic differences in gastric transit times. These and our other findings show that many caregivers continue to base their fasting instructions on the Mendelson1 tradition rather than on evidencebased guidelines.3 We are most concerned about instructions for fasting from clear liquids, since this is where the largest discrepancy exists between ASA recommendations and practice. The ASA guidelines recommend a minimal fast from clear liquids of two hours; by contrast, patients in our studies were instructed to fast from clear liquids for an average of nine hours. In addition, thirst is more bothersome to patients than hunger.5 Thirst, as well as caffeine headaches for those patients who are caffeine-dependent, can be important dissatisfiers for preoperative patients. Fasting from solids is a lesser concern. The average instructed fasting time for solids (ie, 10 hours) is only two hours more than the eight hours recommended by the ASA for a regular meal. Almost half the patients in our investigations fasted from liquids for 12 hours or more and some fasted from liquids for 15 hours or more. The vast majority of our patients were instructed to remain NPO after midnight. The AORN JOURNAL •
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Almost half of the patients in our investigations fasted from liquids for 12 hours or more, and some fasted from liquids for 15 hours or more; the vast majority of patients were instructed to remain NPO after midnight.
proportion of patients scheduled for afternoon surgery who were told to remain NPO after midnight was lower in 2004 than in 2000 (69% versus 81%) but this difference was not statistically significant (P = .19). Our data show average instructed time of fasting for liquids of nine hours in both 2000 and in 2004. Patients’ actual fasting durations for liquids were 11.9 hours in 2000 and 11 hours in 2004. Patients’ actual fasting durations generally are longer than instructed because of individual sleeping and eating schedules. For example, if a female patient who is instructed to be NPO after midnight for surgery scheduled at 10 AM (ie, instructed fast of 10 hours) has dinner at 6 PM and goes to bed at 10 PM, then she actually has fasted for 16 hours before surgery. If she has a snack before bed, her fasting duration would be 12 hours. If the patient had been told she could have clear liquids until 7 AM, however, this could have reduced her thirst, irritability, symptoms of caffeine withdrawal, and susceptibility to dehydration and hypovolemia. Our major concern is instructed rather than actual fasting durations since physicians and nurses have control over the instructed fasting durations. EARLY SURGERIES. One reason stated by physicians and nurses at our facility and elsewhere for the reluctance to give instructions other than NPO after midnight is the possibility that procedures may be moved to an earlier time
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slot.32,33 This concern can be put to rest by our findings in both 2000 and 2004. Fewer than 10% of the studied procedures were moved to an earlier time slot, and the procedures averaged only 33 minutes early in the 2000 study and 56 minutes early in 2004. If the ASA guidelines for preoperative fasting from clear liquids were followed, no procedures would have been cancelled because of this earlier time slot. As Chapman pointed out,34 physicians and nurses tend to exaggerate the variability in the OR schedule. Other researchers found that permitting clear liquids until three hours before surgery did not affect cancellations or delays.32 MEDICATION INSTRUCTION. The significant improvement in instruction about whether to take medications on the morning of surgery was gratifying; however, 13% of patients on routine medications did not receive instructions. Taking medications that should not be taken (eg, medications that increase the chance of bleeding) or not taking medications that should be taken (eg, asthma medications) can increase the risk of adverse operative and postoperative events. A potential participant in a study of preoperative fasting in women having a scheduled cesarean birth7 did not take her asthma medication because she was told to fast. She had an acute asthma attack and the surgery had to be postponed. This highlights the fact that all patients on routine medications need to receive specific instructions about which medications to take before surgery. WHY NPO AFTER MIDNIGHT PERSISTS. Although scientific data are available, resistance to change is significant. Barriers to implementing evidencebased guidelines are complex and multifactorial and are influenced by political, organizational, financial, cultural, and scientific interests.8 Education alone will not “fix” the problem; rather, multimodal strategies are needed. Physicians and nurses prefer to give all preoperative patients one instruction. It is simpler to tell everyone to remain NPO after midnight than to individualize instructions depending on the time of surgery and other factors; however, patients are perfectly capable of stopping solids by a specified time, differentiating between clear and nonclear liquids, and stopping clear liquids
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by a specified time.6,32 Health care providers’ fear that patients cannot or will not follow instructions other than NPO after midnight is patronizing and unjustified. Based on their self reports, the patients in our investigations were overly compliant, fasting longer than instructed, suggesting patients do not want to jeopardize their surgical outcomes. Other major reasons that the “NPO after midnight” ritual persists include the difficulty in changing entrenched traditions that do not seem to be hurting patients, concerns that more liberalized fasting instructions will prevent surgical procedures from being moved to an earlier time, and exaggerated fears about the risk of pulmonary aspiration.8 Lack of knowledge about the ASA preoperative fasting guidelines, the hundreds of controlled trials demonstrating the safety and efficacy of liberalized preoperative fasting, and the difference in gastric transit of liquids versus solids contributes to the perpetuation of the “NPO after midnight” tradition. Many health care providers still believe the myth that prolonged fasting reduces gastric volumes and are unfamiliar with the studies that show consumption of clear liquids several hours before surgery actually may decrease gastric volumes.4,23 Longer fasting is not better or safer; basing fasting on evidence-based guidelines is better and safer.
IMPLICATIONS
FOR
PRACTICE
Because the “NPO after midnight” tradition is difficult to change and new scientific evidence is not enough to change practice,8,35 nurses, anesthesia care providers, and surgeons must work together to actively implement evidence-based practice. We recommend continuing widespread education about the ASA guidelines and their strong supporting evidence for physicians and nurses in hospitals, day surgery facilities, and physicians’ offices. We suggest focusing on • liberalizing fasting instructions for clear liquids for all patients, • differentiating between clear liquids and solids in fasting instructions, and • targeting the afternoon surgery patients to make sure they are instructed to have clear liquids or a light breakfast the morning of surgery.
Health care providers’ fear that patients cannot or will not follow instructions other than NPO after midnight is patronizing and unjustified.
Afternoon surgery patients have the longest preoperative fasting times and are at the greatest risk for adverse effects of prolonged fasting. In addition, preprinted orders need to be evaluated and options other than NPO after midnight need to be included. It may be necessary to track fasting times on a unit to make it more obvious to caregivers how long patients are fasting, or to have a “model unit” to demonstrate the safety and ease of liberalized fasting in the facility. It also is important to educate consumers about preoperative fasting guidelines. Consumers may be the most important agents for change. Patients scheduled for afternoon surgery need to ask for a light meal and clear liquids; patients who do not ask may go hungry and thirsty. Nurses can make a big difference in preventing unnecessarily long preoperative fasting. Nurses can cite evidence from the ASA guidelines, make recommendations to physicians, and lead the way toward implementing best practices. Nurses can use 2-4-6-8 as a reminder that the minimum fasting guidelines are • two hours for clear liquids, • four hours for breast milk, • six hours for milk or a light meal, and • eight hours for a regular meal. This is safe for healthy patients of all ages undergoing elective procedures who have no contraindications. It is time to base our practice on up-to-date evidence as opposed to evidence from the 1940s. We hope this article will serve as a catalyst for renewed efforts to update outmoded fasting practices, and will encourage individual AORN JOURNAL •
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nurses to act as vocal and knowledgeable advocates for the fasting patient. Acknowledgements: The authors would like to thank Margaret Martin, MSN, RN, BC, CIC, director, patient care resources, Presbyterian Hospital of Dallas, Texas, and David Eubanks, MSN, RN, former administrative director clinical learning academic partnerships, Arlington, TX, for administrative support; Richard Gilder, BSN, RN, former clinical consultant/outcomes analyst, Texas Health Resources, Arlington, TX, for statistical analysis assistance; the nurses who helped with data collection, the Nursing Research Committee, and the patients who participated; and Cathy Y. Nakashima, MLS, MBA, and Jeanette Prasifka, MLS, medical librarians, Presbyterian Hospital of Dallas, for library services. We also thank Joy Don Baker, PhD, RN-BC, CNE, CNOR, NEA-BC, associate clinical professor and director, distance education, University of Texas at Arlington, and Kathy A. Baker, PhD, RN, ACNS-BC, CGRN, associate professor, director, doctor of nursing practice program, Texas Christian University, Fort Worth, Texas, for their thoughtful reviews of an earlier version of this article. Editor’s note: Excel is a registered trademark of Microsoft Corp, Redmond, WA.
REFERENCES 1. Mendelson CL. The aspiration of stomach contents into the lungs during obstetric anesthesia. Amer J Obstet Gynecol. 1946;52:191-205. 2. Pandit UA, Pandit SK. Fasting before and after ambulatory surgery. J Perianesth Nurs. 1997;12(3): 181-187. 3. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: a report by the American Society of Anesthesiologist Task Force on Preoperative Fasting. Anesthesiology. 1999; 90(3):896-905. 4. Agarwal A, Chari P, Singh H. Fluid deprivation before operation. The effect of a small drink. Anaesthesia. 1989;44(8):632-634. 5. Crenshaw JT, Winslow EH. Preoperative fasting: old habits die hard. Am J Nurs. 2002;102(5):36-45. 6. Winslow EH, Crenshaw JT, Warner MA. Best practices shouldn’t be optional: prolonged fasts aren’t more effective—or even safer. Am J Nurs. 2002;102(6):59, 63. 7. Crenshaw JT, Winslow EH. Actual versus in-
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structed fasting times and associated discomforts in women having scheduled cesarean birth. J Obstet Gynecol Neonatal Nurs. 2006;35(2):257-264. 8. Bosse G, Breuer JP, Spies C. The resistance to changing guidelines—what are the challenges and how to meet them. Best Pract Res Clin Anaesthesiol. 2006;20(3):379-395. 9. Davis R. Pre-surgical fasting slow to be taken off the menu. USA Today. May 7, 2002. 10. Lange DP. No need to go on empty so long before surgery. Los Angeles Times. May 13, 2002:S2. 11. Kohn D. Slow demise for long preoperative fasts; doctors ban food, drink for hours before surgery, though the practice has little benefit. The Baltimore Sun. July 23, 2006:1A. 12. Maltby JR. Fasting from midnight—the history behind the dogma. Best Pract Res Clin Anaesthesiol. 2006;20(3):363-378. 13. Lister JL. The Collected Papers of Joseph Baron Lister. Vol 1. Special ed. Birmingham, AL: Classics of Medicine Library; 1979:172. 14. Brown DL, Heard SO, Stevens DS, Kirby RR. Preoperative evaluation of high-risk surgical patients. In: Civetta JM, Taylor RW, Kirby RR, eds. Critical Care. 3rd ed. Philadelphia: LippincottRaven; 1997:999-1007. 15. Mecca RS. Postoperative recovery. In: Barash PG, Cullen BF, Stoelting RK, eds. Clinical Anesthesia. Philadelphia, PA: Lippincott Williams & Wilkins; 1989:1516. 16. Schreiner MS. Preoperative and postoperative fasting in children. Pediatr Clin North Am. 1994; 41(1):111-120. 17. Olsson GL, Hallen B, Hambraeus-Jonzon K. Aspiration during anaesthesia: a computer-aided study of 185,358 anaesthetics. Acta Anaesthesiol Scand. 1986;30(1):84-92. 18. Tiret L, Nivoche Y, Hatton F, Desmonts JM, Vourc’h G. Complications related to anaesthesia in infants and children. A prospective survey of 40240 anaesthetics. Br J Anaesth. 1988;61(3):263-269. 19. Warner MA, Warner ME, Weber JG. Clinical significance of pulmonary aspiration during the perioperative period. Anesthesiology. 1993;78(1):56-62. 20. Miller M, Wishart HY, Nimmo WS. Gastric contents at induction of anaesthesia. Is a 4-hour fast necessary? Br J Anaesth. 1983;55(12):1185-1188. 21. Hutchinson A, Maltby JR, Reid CR. Gastric fluid volume and pH in elective inpatients. Part I: coffee or orange juice versus overnight fast. Can J Anaesth. 1988;35(1):12-15. 22. Maltby JR, Sutherland AD, Sale JP, Shaffer EA. Preoperative oral fluids: is a five-hour fast justified prior to elective surgery? Anesth Analg. 1986;65: 1112-1116. 23. Maltby JR, Koehli N, Ewen A, Shaffer EA. Gastric fluid volume, pH, and emptying in elective inpatients. Influences of narcotic-atropine premedication, oral fluid, and ranitidine. Can J Anaesth. 1988;35(6):562-566. AORN JOURNAL •
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24. Sutherland AD, Maltby JR, Sale JP, Reid CR. The effect of preoperative oral fluid and ranitidine on gastric fluid volume and pH. Can J Anaesth. 1987; 34(2):117-121. 25. George JD. New clinical method for measuring the rate of gastric emptying: the double sampling test meal. Gut. 1968;9(2):237-242. 26. Maltby JR. New guidelines for preoperative fasting. Can J Anaesth. 1993;40(5 Pt 2):R113-R121. 27. Minami H, McCallum RW. The physiology and pathophysiology of gastric emptying in humans. Gastroenterology. 1984;86(6):1592-1610. 28. Pearse R, Rajakulendran Y. Pre-operative fasting and administration of regular medications in adult patients presenting for elective surgery. Has the new evidence changed practice? Eur J Anaesthesiol. 1999;16(8):565-568. 29. Statistical Package for Social Sciences, version 15.0. Chicago, IL: SPSS; 2006. 30. Shime N, Ono A, Chihara E, Tanaka Y. Current practice of preoperative fasting: a nationwide survey in Japanese anesthesia-teaching hospitals. J Anesth. 2005;19(3):187-192. 31. Maltby JR, Pytka S, Watson NC, Cowan RA, Fick GH. Drinking 300 mL of clear fluid two hours before surgery has no effect on gastric fluid volume and pH in fasting and non-fasting obese patients. Can J Anaesth. 2004;51(2):111-115. 32. Murphy GS, Ault ML, Wong HY, Szokol JW.
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The effect of a new NPO policy on operating room utilization. J Clin Anesth. 2000;12(1):48-51. 33. Doswell WM, Jones MA, O’Donnell JM. One size may not fit all: it's not always possible—or appropriate—to use the ASA guidelines for preoperative fasting. Am J Nurs. 2002;102(6):58, 61. 34. Chapman A. Current theory and practice: a study of pre-operative fasting. Nurs Stand. 1996; 10(18):33-36. 35. Søreide E, Ljungqvist O. Modern preoperative fasting guidelines: a summary of the present recommendations and remaining questions. Best Pract Res Clin Anaesthesiol. 2006;20(3):483-491.
Jeannette T. Crenshaw, MSN, RN, LCCE, FACCE, IBCLC, is a clinical education specialist at Texas Health Resources, the Center for Learning, Arlington, TX, and graduate faculty for the Nursing Administration Program at the University of Texas at Arlington School of Nursing. Elizabeth H. Winslow, PhD, RN, FAAN, is the research consultant at Presbyterian Hospital of Dallas, Texas.
Electronic Health Records Improve Quality of Care
P
hysicians who use outpatient electronic health records (EHRs) believe they improve quality of care, and usage has increased in the past year, according to an article in the July 3, 2008, issue of The New England Journal of Medicine. Researchers included 2,758 physicians in their national survey, which garnered a 62% response rate between September 2007 and March 2008. For the analysis, researchers differentiated between fully functional and basic systems. Fully functional systems were defined as those that could • record clinical and demographic data; • view and manage laboratory test results and imaging; • manage order entry (eg, electronic prescriptions); and • support clinical decisions (eg, medication interactions or contraindications). Basic systems, by comparison, did not have orderentry capabilities or clinical-decision support. Survey results showed 4% of physicians used fully functional EHRs and 13% used a basic system. Seventy-one percent of physicians using fully func-
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tional systems integrated it with an electronic system at the hospital where they admitted patients, compared to 56% of basic system users. Those using either type of EHR generally were satisfied overall (ie, 93% for fully functional versus 88% for basic) and were satisfied with system reliability (ie, 90% for fully functional versus 79% for basic). Those who were most likely to use EHRs were • primary care physicians, • physicians practicing in large groups, and • hospitals or medical centers. Physicians in the western United States and younger physicians were also more likely to have incorporated EHRs into their practices. Of the 83% of respondents not using an EHRs, 16% had purchased but not yet incorporated a system and 26% stated their intent to purchase one within two years. The most common reason for not using an EHR was the cost. DesRoches CM, Campbell EG, Rao SR et al. Electronic health records in ambulatory care—a national survey of physicians. N Engl J Med. 2008;359(1):50-60.