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A study of surgical patients' temperatures
aintenance of body temperature in patients undergoing surgical intervention is a major concern of operating room nurses and physicians caring for surgical patients. A search of the literature revealed little mention of the incidence of postoperative shivering 9s it relates to ope? a!mg room technique and preoperative care of the snrgical patient. The prevention of body heat loss in these patients is seldom discussed nor is there mention that a drop in body temperature often occurs in adult patients during surgery. Body temperature of adult patients typically falls 0.5 C to 1.5C during surgical operations under general anesthesia. Postoperative shivering, which has a reported incidence of up to 5w0,~ often occurs in patients with decreased body t e m p e r a t ~ r e . ~ Shivering can increase oxygen consumption up to 400%,4 and the muscular activity associated with shivering can make blood pressure, heart sounds, and respiratory rates difficult t o monitor during the postanesthetic recovery period. Causes of decreased body temperature may be varied. Anesthetic drugs and drugs used to supplement anesthesia can depress the heat-regulating mechanisms, resulting in a fall in body temperature. This effect can be produced by depressing the hypothalmic thermoregulatory area, by abolishing shivering and voluntary muscle activity, by causing cutaneous vasodilat i ~ n and/or , ~ by reducing afferent stimuli from cutaneous receptors through the spinal cord.6 Other factors that contribute to a lowered body temperature in the surgical patient include the administration of intravenous fluids and blood transfusions, preparation of the skin for incision, exposure of the abdominal cavity, age, weight, and duration of the operati~n.~
M
A study of surgical patients’ temperatures Effects of preoperative procedures on patients’ body ternperatures Judith M Ozuna, RN
240
A n R N Journal, August 1978, Vol28, No 2
Body temperature changes during operations and anesthesia have been studied extensively.* However, I was unable to find any studies pertaining to the events of the preoperative period and their effects on body temperature of surgical patients. I was surprised by this lack of information since drugs given can interfere with thermal balance, and other procedures such as skin preparation, nerve blocks, removal of clothing and blankets, and transportation through cool corridors all contribute to the lowering of body temperature. 1decided t o examine the relative contribution of the preoperative period and the intraoperative period to the ob-
Ozuna, R N , MN, is an instructor, University of Washington School of Nursing, Seattle, and a clinical nurse specialist, Epilepsy Center, University of Washington. She received her BS and M N from the University of Washington. The author would like to thank George Brengelrnann, Department of Physiology and Biophysics, University of Washington, for his help in developing the temperature correction charts and for ensuring the accuracy of the temperature recording instrument. The author would also like to thank Louise Mansfield. Department of Physiological Nursing, University of Washington, for her helpful suggestions. Preparation of this manuscript was supported in part by BRSG Grant No RR05758, Biomedical Research Support Program, Divisionof Research Resource, National Institutes of Health, US Department of Health. Education, and Welfare. Judith M
served total change in body temperature, to identify factors associated with t e m p e r a t u r e changes d u r i n g t h e preoperative period, and to establish the relationships between the oral and esophageal t e m p e r a t u r e s d u r i n g surgery to check the reliability of oral temperature monitoring. Body temperature was monitored in the posterior sublingual pocket and in the lower esophagus using thermistors and a portable six-channel electric thermometer. Three of the six channels were used with each subject-one for oral temperature, one for esophageal temperature, and one for room air temperature. Two flexible oral probes and two esophageal probes were used to allow time for sterilization between operations. The esophageal temperature probe was a component of a n esophageal stethoscope used by t h e anesthesiologist to monitor heart rate, breath sounds, and temperature. In a well-stirred water bath, t h e thermistors were calibrated against a laboratory thermometer with accuracy traceable to the National Bureau of Standards. The electric thermometer was adjusted each day for mechanical zero set and deffection produced by a fixed resistor chosen t o correspond to 36.02 C. The study sample, nine adult females and one adult male, was chosen from the surgical patients of a private general surgeon a t a 300-bed metropolitan hospital. On the day of surgery, all subjects were free of any evidence of infection and had oral temperatures no higher then 37.5 C. All patients were scheduled for major surgical procedures involving organs of the upper abdomen, excluding appendectomy and herniorrhaphy procedures. Preanesthesia medication included e i t h e r morphine sulfate or meperidine hydrochloride. Anesthesia consisted of a barbiturate drug, intercostal nerve block, intubation, and
A O H N -loiirrirrl Arigitst 1978, Vol28. No 2
24 1
38
I
I
33
0
1
I
1
I
40
I
I
1
I
80 Time, minutes
I
I
I
I
I
1
I 160
I
120
200
Fig 1. Oral (dots) and esophageal (triangles) temperatures in patient 9. Times indicated and associated events are: TI, preoperative medication; Tz, one-half hour after
medication; T3, on entering induction room; T q on entering operating room; T5, coincident with surgical incision; T6, end of anesthesia.
nitrous oxide. Each patient signed a written consent form approved by the institutional Human Subjects Review Committee. All oral temperatures were taken in the left posterior sublingual pocket because the endotracheal tube was in the right side of the mouth. Erickson has shown that temperature measured in this site is slightly higher than in the right sublingual pocket, although the difference is neither statistically nor clinically ~ i g n i f i c a n t . ~ The first oral temperature (TI) for each patient was taken not more than t e n minutes before t h e preoperative medication was given. The probe was left in place for three minutes t,o allow the instrument to stabilize The sir temperature was also recorded at this time and with all subsequent reading-,. The second oral temperature (Tr?)wss taken
a s close as possible to one-half hour after administration of the premedication. On four occasions, that time coincided with the transportation of the subject to the induction room, in which case the temperatures for both times (onehalf hour after premedication and entry to the induction room) were recorded simultaneously. The third oral temperature ("3) was taken within five minutes of the patient arrival at the induction room. The time each patient spent in the induction room varied from 22 minutes to 65 minutes. All patients were covered with a gown and two cotton bath blankets. During this period, each patient had an intravenous line started and was then turned to a prone position with both arms placed in a dependent position over the side of the stretcher. The back was bared to the buttocks. Povidone-iodine solution was
242
AORN Journal, August 1978, Vol28, No 2
painted on the back from the upper scapulae to the mid-lumbar region and around both sides of the rib cage. At this time the patient was rendered unconscious by an intravenous injection of a short-acting barbiturate. The anesthesiologist then injected 4 to 5 cc of 0.5% bupivacaine hydrochloride with epinephrine around t h e intercostal nerves of the seven or eight lower ribs. Eight patients also received a deep splanchnic block with diluted bupivacaine hydrochloride solution. The b a r b i t u r a t e was discontinued toward the end of the block procedure. The patient was then transported to the operating room i n a semi-conscious state, still prone. On arrival i n the operating room, the patient was immediately placed in a supine position on the operating table. The fourth oral temperature (T4)was taken at this time. After the patient was intubated, the anesthesiologist placed the esophageal stethoscope containing the temperature probe 37 to 38 cm beyond the teeth into
T
T
the esophagus. The flexible oral probe was placed in the left side of the mouth by a blind approach since the endotracheal tube, oral airway, and esophageal stethoscope were already in place. The oral, esophageal, and air temperature readings were begun five to ten minutes after t h e subject was intubated. Temperature number five (T5) coincided with the making of the surgical incision. Temperatures were recorded every five minutes until the subject was extubated (%). Figure 1shows a typical record of oral a n d esophageal temperatures. The mean temperatures and standard errors of the means for six different time points (Ti to T6) are shown in Figure 2. The total drops in oral temperature for all patients during the preoperative period, the intraoperative period, and the total study period are shown in Table 1. All ten patients experienced a fall in body temperature beginning when the preoperative medication was given and lasting through t h e termination of
T
T
Ti
Tz
T3
T4
T5
T6
Fig 2. Mean oral temperatures and standard errors of the means at the six times defined in the text and in Fig 7 . N = 10.
AORN Journal, August 1978, V o l 2 8 , N o 2
243
Table 1
Observed temperature (C) differences in ten surgical patients in relation to preoperative and intraoperative events Preoperative oral temperature Subject 1 2 3 4 5 6 7 8 9 10
Mean
drop (Ti to Tz) 1.26 .63 1.36 .94 .67 1.01 .54 1.90 1.66 1.11 1.1 1
lntraoperative oral temperature drop (T5
to
.48 .59 .83 .77 .35 -.04 .06 .43 .30 -.03 .37
anesthesia. The mean preoperative oral drop w a s 1.11 C and the mean intraoperative oral drop was 0.37 C. The overall oral temperature drop ranged from 0.60 C to 2.33 C, with a mean of 1.48C . The data obtained in this study generally showed parallel behavior of oral and esophageal temperatures, therefore, oral measurement was considered to be a reliable indicator of deep body temperature during this study. The ambient air temperature was recorded each time a subject’s temperature was taken. Temperature of the patient’s room varied from 21.40 C to 24.85 C . The induction room had a similar range, 22.50 C to 23.90 C. Operating room temperatures were much cooler, ranging from 18.63 C to 22.80 C. Discussion. In all patients, the oral temperature drop in the preoperative period was greater than i n the intraoperative period. The largest temperature drop occurred in the induction room (T3 to T4), with the mean being 0.73
244
T6)
lntraoperative esophageal temperature
Total oral temperature
drop (T5 tO T6) .16 .65 .78 .71 -.15 -.11 .22 .36 .37 .09 .28
drop (Ti to T6) 1.74 1.22 2.1 9 1.71 1.02 .97
.60 2.33 I .96 1.08 1.48
C . Thus, factors that contributed most to the preoperative temperature drop were skin preparation of the back, administration of a barbiturate, and administration of an intercostal nerve block. Heat loss was probably accounted for by evaporation of the skin preparation solution as well as by radiation and convection from the exposed skin surface. The unconscious patient cannot use mechanisms normally employed to conserve body heat such as movement o r adding covers. By depressing transmission in the sympathetic ganglia, the barbiturate created a loss of vasoconstrictor tone, bringing more blood flow and therefore more heat to the body surface. Intercostal nerve block does not involve the sympathetic rami communicans or the sympathetic ganglia.’O However, a deep splanchnic block does denervate the sympathetic fibers that innervate the viscera. Loss of vasoconstrictor tone due to the splanchnic blockade was probably not as significant as was the loss of cutaneous va-
AORN Journal, August 1978, Vol28, No 2
soconstriction due to the preanesthetic narcotic and barbiturate. The study suggest that low temperatures of surgical patients on arrival in the recovery room may not completely or even primarily be t h e result of activities during t h e intraoperative period, but may be related to procedures performed during the preoperative preparation of the patient. In this study, a large percent of the recorded fall in body temperature occurred from the time of the patient's arrival in the surgical area to the time of surgical incision. During this time, cooling could probably be reduced by nursing measures designed to conserve body heat. Preoperative nursing procedures should be planned to include maintenance of thermal balance by reducing the exposed body surface area and decreasing the time the surgical patient is exposed. Thermal blankets could be substituted for bath blankets since these could safely be used in the induction room. Radiant heat would help to prevent heat loss to exposed body areas. Shivering is often associated with lowered body temperature during the postoperative period. This shivering places a n added stress on t h e cardiopulmonary system and contributes to patient discomfort. Findings from this study indicate that more attention should be given to body temperature maintenance during the preoperative period as well a s the intraoperative period. Body temperature monitoring and appropriate adjustment of t h e thermal environment of the surgical patient should be primary concerns of nursing personnel, both on the patient unit and in the operating suite. 0
3. Goldberg, Roe, "Temperature changes"; H Jones, C McLaren, "Postoperative shivering and hypoxaemia after halothane, nitrous oxide and oxygen anaesthesia," British Journal of Anaesthisia 37 (1965) 35-40; C Stephen, "Post-operativetemperature changes," Anesthesiology 22 (SepternberOctober 1961) 795-799. 4. Jones, McLaren, "Postoperative shivering." 5. S Horvath, "The metabolic cost of shivering," Journal of Applied Physiology 8 (May 1956) 595-
602. 6. W Wylie, A Practice of Anesthesia (Chicago: Year Book Publishers, Inc, 1972) 1275, 1288. 7. Stephen, "Post-operative temperature changes," M Halsey,"Mechanisms of general anesthesia," in Anesthetic Uptake and Action, E Eger, ed. (Baltimore: Williams and Wilkins Go, 1974) 45-76. 8. Goldberg, Roe, "Temperature changes"; Stephen, "Postoperative temperature changes"; Halsey, "Mechanisms of general anesthesia"; C Roe, "Temperature regulation and energy metabolism in surgical patients," Progress in Surgery 12 (1973) 96-127; R Morris, "influence of ambient temperature on patient temperature during intra-abdominal surgery," Annals of Surgery 173 (February 1971) 230-233. 9. R Erickson, "Thermometer placement for oral temperature measurement in febrile adults," lnternational Journal of Nursing Studies 13 (1976) 199-
208. 10. J Bonica. Tbe Management of Pain (Phiidelphia: Lea & Febiger, 1954) 332.
Notes 1. M Goldberg, C Roe, "Temperature changes during anesthesia and operations," Archives of Surgery 98 (August 1966) 365-374 2. S Liem, J Aldrete, "Control of postanesthetic shivering," Canadian Anaestbetists' Society Journal 21 (September 1974) 506-510.
AORN Journal, August 1978, Vol28, No 2
245
M
A study of surgical patients’ temperatures Effects of preoperative procedures on patients’ body ternperatures Judith M Ozuna, RN
240
A n R N Journal, August 1978, Vol28, No 2
Body temperature changes during operations and anesthesia have been studied extensively.* However, I was unable to find any studies pertaining to the events of the preoperative period and their effects on body temperature of surgical patients. I was surprised by this lack of information since drugs given can interfere with thermal balance, and other procedures such as skin preparation, nerve blocks, removal of clothing and blankets, and transportation through cool corridors all contribute to the lowering of body temperature. 1decided t o examine the relative contribution of the preoperative period and the intraoperative period to the ob-
Ozuna, R N , MN, is an instructor, University of Washington School of Nursing, Seattle, and a clinical nurse specialist, Epilepsy Center, University of Washington. She received her BS and M N from the University of Washington. The author would like to thank George Brengelrnann, Department of Physiology and Biophysics, University of Washington, for his help in developing the temperature correction charts and for ensuring the accuracy of the temperature recording instrument. The author would also like to thank Louise Mansfield. Department of Physiological Nursing, University of Washington, for her helpful suggestions. Preparation of this manuscript was supported in part by BRSG Grant No RR05758, Biomedical Research Support Program, Divisionof Research Resource, National Institutes of Health, US Department of Health. Education, and Welfare. Judith M
served total change in body temperature, to identify factors associated with t e m p e r a t u r e changes d u r i n g t h e preoperative period, and to establish the relationships between the oral and esophageal t e m p e r a t u r e s d u r i n g surgery to check the reliability of oral temperature monitoring. Body temperature was monitored in the posterior sublingual pocket and in the lower esophagus using thermistors and a portable six-channel electric thermometer. Three of the six channels were used with each subject-one for oral temperature, one for esophageal temperature, and one for room air temperature. Two flexible oral probes and two esophageal probes were used to allow time for sterilization between operations. The esophageal temperature probe was a component of a n esophageal stethoscope used by t h e anesthesiologist to monitor heart rate, breath sounds, and temperature. In a well-stirred water bath, t h e thermistors were calibrated against a laboratory thermometer with accuracy traceable to the National Bureau of Standards. The electric thermometer was adjusted each day for mechanical zero set and deffection produced by a fixed resistor chosen t o correspond to 36.02 C. The study sample, nine adult females and one adult male, was chosen from the surgical patients of a private general surgeon a t a 300-bed metropolitan hospital. On the day of surgery, all subjects were free of any evidence of infection and had oral temperatures no higher then 37.5 C. All patients were scheduled for major surgical procedures involving organs of the upper abdomen, excluding appendectomy and herniorrhaphy procedures. Preanesthesia medication included e i t h e r morphine sulfate or meperidine hydrochloride. Anesthesia consisted of a barbiturate drug, intercostal nerve block, intubation, and
A O H N -loiirrirrl Arigitst 1978, Vol28. No 2
24 1
38
I
I
33
0
1
I
1
I
40
I
I
1
I
80 Time, minutes
I
I
I
I
I
1
I 160
I
120
200
Fig 1. Oral (dots) and esophageal (triangles) temperatures in patient 9. Times indicated and associated events are: TI, preoperative medication; Tz, one-half hour after
medication; T3, on entering induction room; T q on entering operating room; T5, coincident with surgical incision; T6, end of anesthesia.
nitrous oxide. Each patient signed a written consent form approved by the institutional Human Subjects Review Committee. All oral temperatures were taken in the left posterior sublingual pocket because the endotracheal tube was in the right side of the mouth. Erickson has shown that temperature measured in this site is slightly higher than in the right sublingual pocket, although the difference is neither statistically nor clinically ~ i g n i f i c a n t . ~ The first oral temperature (TI) for each patient was taken not more than t e n minutes before t h e preoperative medication was given. The probe was left in place for three minutes t,o allow the instrument to stabilize The sir temperature was also recorded at this time and with all subsequent reading-,. The second oral temperature (Tr?)wss taken
a s close as possible to one-half hour after administration of the premedication. On four occasions, that time coincided with the transportation of the subject to the induction room, in which case the temperatures for both times (onehalf hour after premedication and entry to the induction room) were recorded simultaneously. The third oral temperature ("3) was taken within five minutes of the patient arrival at the induction room. The time each patient spent in the induction room varied from 22 minutes to 65 minutes. All patients were covered with a gown and two cotton bath blankets. During this period, each patient had an intravenous line started and was then turned to a prone position with both arms placed in a dependent position over the side of the stretcher. The back was bared to the buttocks. Povidone-iodine solution was
242
AORN Journal, August 1978, Vol28, No 2
painted on the back from the upper scapulae to the mid-lumbar region and around both sides of the rib cage. At this time the patient was rendered unconscious by an intravenous injection of a short-acting barbiturate. The anesthesiologist then injected 4 to 5 cc of 0.5% bupivacaine hydrochloride with epinephrine around t h e intercostal nerves of the seven or eight lower ribs. Eight patients also received a deep splanchnic block with diluted bupivacaine hydrochloride solution. The b a r b i t u r a t e was discontinued toward the end of the block procedure. The patient was then transported to the operating room i n a semi-conscious state, still prone. On arrival i n the operating room, the patient was immediately placed in a supine position on the operating table. The fourth oral temperature (T4)was taken at this time. After the patient was intubated, the anesthesiologist placed the esophageal stethoscope containing the temperature probe 37 to 38 cm beyond the teeth into
T
T
the esophagus. The flexible oral probe was placed in the left side of the mouth by a blind approach since the endotracheal tube, oral airway, and esophageal stethoscope were already in place. The oral, esophageal, and air temperature readings were begun five to ten minutes after t h e subject was intubated. Temperature number five (T5) coincided with the making of the surgical incision. Temperatures were recorded every five minutes until the subject was extubated (%). Figure 1shows a typical record of oral a n d esophageal temperatures. The mean temperatures and standard errors of the means for six different time points (Ti to T6) are shown in Figure 2. The total drops in oral temperature for all patients during the preoperative period, the intraoperative period, and the total study period are shown in Table 1. All ten patients experienced a fall in body temperature beginning when the preoperative medication was given and lasting through t h e termination of
T
T
Ti
Tz
T3
T4
T5
T6
Fig 2. Mean oral temperatures and standard errors of the means at the six times defined in the text and in Fig 7 . N = 10.
AORN Journal, August 1978, V o l 2 8 , N o 2
243
Table 1
Observed temperature (C) differences in ten surgical patients in relation to preoperative and intraoperative events Preoperative oral temperature Subject 1 2 3 4 5 6 7 8 9 10
Mean
drop (Ti to Tz) 1.26 .63 1.36 .94 .67 1.01 .54 1.90 1.66 1.11 1.1 1
lntraoperative oral temperature drop (T5
to
.48 .59 .83 .77 .35 -.04 .06 .43 .30 -.03 .37
anesthesia. The mean preoperative oral drop w a s 1.11 C and the mean intraoperative oral drop was 0.37 C. The overall oral temperature drop ranged from 0.60 C to 2.33 C, with a mean of 1.48C . The data obtained in this study generally showed parallel behavior of oral and esophageal temperatures, therefore, oral measurement was considered to be a reliable indicator of deep body temperature during this study. The ambient air temperature was recorded each time a subject’s temperature was taken. Temperature of the patient’s room varied from 21.40 C to 24.85 C . The induction room had a similar range, 22.50 C to 23.90 C. Operating room temperatures were much cooler, ranging from 18.63 C to 22.80 C. Discussion. In all patients, the oral temperature drop in the preoperative period was greater than i n the intraoperative period. The largest temperature drop occurred in the induction room (T3 to T4), with the mean being 0.73
244
T6)
lntraoperative esophageal temperature
Total oral temperature
drop (T5 tO T6) .16 .65 .78 .71 -.15 -.11 .22 .36 .37 .09 .28
drop (Ti to T6) 1.74 1.22 2.1 9 1.71 1.02 .97
.60 2.33 I .96 1.08 1.48
C . Thus, factors that contributed most to the preoperative temperature drop were skin preparation of the back, administration of a barbiturate, and administration of an intercostal nerve block. Heat loss was probably accounted for by evaporation of the skin preparation solution as well as by radiation and convection from the exposed skin surface. The unconscious patient cannot use mechanisms normally employed to conserve body heat such as movement o r adding covers. By depressing transmission in the sympathetic ganglia, the barbiturate created a loss of vasoconstrictor tone, bringing more blood flow and therefore more heat to the body surface. Intercostal nerve block does not involve the sympathetic rami communicans or the sympathetic ganglia.’O However, a deep splanchnic block does denervate the sympathetic fibers that innervate the viscera. Loss of vasoconstrictor tone due to the splanchnic blockade was probably not as significant as was the loss of cutaneous va-
AORN Journal, August 1978, Vol28, No 2
soconstriction due to the preanesthetic narcotic and barbiturate. The study suggest that low temperatures of surgical patients on arrival in the recovery room may not completely or even primarily be t h e result of activities during t h e intraoperative period, but may be related to procedures performed during the preoperative preparation of the patient. In this study, a large percent of the recorded fall in body temperature occurred from the time of the patient's arrival in the surgical area to the time of surgical incision. During this time, cooling could probably be reduced by nursing measures designed to conserve body heat. Preoperative nursing procedures should be planned to include maintenance of thermal balance by reducing the exposed body surface area and decreasing the time the surgical patient is exposed. Thermal blankets could be substituted for bath blankets since these could safely be used in the induction room. Radiant heat would help to prevent heat loss to exposed body areas. Shivering is often associated with lowered body temperature during the postoperative period. This shivering places a n added stress on t h e cardiopulmonary system and contributes to patient discomfort. Findings from this study indicate that more attention should be given to body temperature maintenance during the preoperative period as well a s the intraoperative period. Body temperature monitoring and appropriate adjustment of t h e thermal environment of the surgical patient should be primary concerns of nursing personnel, both on the patient unit and in the operating suite. 0
3. Goldberg, Roe, "Temperature changes"; H Jones, C McLaren, "Postoperative shivering and hypoxaemia after halothane, nitrous oxide and oxygen anaesthesia," British Journal of Anaesthisia 37 (1965) 35-40; C Stephen, "Post-operativetemperature changes," Anesthesiology 22 (SepternberOctober 1961) 795-799. 4. Jones, McLaren, "Postoperative shivering." 5. S Horvath, "The metabolic cost of shivering," Journal of Applied Physiology 8 (May 1956) 595-
602. 6. W Wylie, A Practice of Anesthesia (Chicago: Year Book Publishers, Inc, 1972) 1275, 1288. 7. Stephen, "Post-operative temperature changes," M Halsey,"Mechanisms of general anesthesia," in Anesthetic Uptake and Action, E Eger, ed. (Baltimore: Williams and Wilkins Go, 1974) 45-76. 8. Goldberg, Roe, "Temperature changes"; Stephen, "Postoperative temperature changes"; Halsey, "Mechanisms of general anesthesia"; C Roe, "Temperature regulation and energy metabolism in surgical patients," Progress in Surgery 12 (1973) 96-127; R Morris, "influence of ambient temperature on patient temperature during intra-abdominal surgery," Annals of Surgery 173 (February 1971) 230-233. 9. R Erickson, "Thermometer placement for oral temperature measurement in febrile adults," lnternational Journal of Nursing Studies 13 (1976) 199-
208. 10. J Bonica. Tbe Management of Pain (Phiidelphia: Lea & Febiger, 1954) 332.
Notes 1. M Goldberg, C Roe, "Temperature changes during anesthesia and operations," Archives of Surgery 98 (August 1966) 365-374 2. S Liem, J Aldrete, "Control of postanesthetic shivering," Canadian Anaestbetists' Society Journal 21 (September 1974) 506-510.
AORN Journal, August 1978, Vol28, No 2
245