Notes from the AmericanSociety of Anesthesiologists Annual Meeting

Notes from the American Society of Anesthesiologists Annual Meeting DENISE

O'BRIEN, BSN,

AST OCTOBER, key ASPAN leaders attended the 1999 American Society of Anesthesiologists (ASA) Annual Meeting in Dallas, TX. Vice President/President Elect Nancy Saufl, Public Relations and Marketing Chair Susan Shelander, Executive Director Kevin Dill, ASPAN member and Anesthesia Patient Safety Foundation Board member David Wharton. member Mary Mulkay, and Interim JoPAN Editor Denise O'Brien met for the opening ceremonies on October 10 as President Myrna Mamaril was introduced to the House of Delegates and officers of the ASA. On subsequent days, the ASPAN members staffed an ASPAN booth in the Scientific Exhibit area, visited and met with exhibitors, attended lectures and presentations, and participated an meetings of the Anesthesia Care Team and the Anesthesia Patient Safety Foundation. Each year at the ASA annual meeting, research findings are presented. Once again, we will highlight some of those findings on these pages, those of greatest interest to perianesthesia nurses. To read more about the annual meeting, review abstracts of poster presentanons, and for general information about the ASA, you can visit the ASA web site at http://www.asahq.org.

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RESEARCHERS WARN OF POTENTIAL HERBAL ANESTHESIA INTERACTIONS

Herbal medicines are being taken by millions of people and according to Charles H. McLeskey, MD, chair of anesthesiology and director of penoperative services at Scott & White Hospital of Texas A & M University, he warned " .. we don't know enough about these products, their effects or interactions." Patients need to inform their anesthesia Journal of PerlAnesthesta Nursing, Vo115, No 2 (Aprd), 2000 pp 129-132

RN, CPAN, CAPA

care providers about all the medications they are taking, including herbal products and over-thecounter remedies. Anesthesia care providers need to begin to ask all their patients specifically about herbal medicines. Dr McLeskey surveyed surgical patients, asking what herbs they consumed. The most commonly taken herbal was gingko biloba (32%) which has been linked with an increased risk of bleeding. This could lead to excessive blood loss during surgery. Other herbal medicines have also been linked to interference with blood clotting, including feverfew. Kava, which is used as a relaxant, may have additive effects when combined with sedatives administered before and during procedures. Current recommendations suggest herbal medications be stopped 2 to 3 weeks before surgery. If this is impossible, instruct patients to bring all their medications with them to the surgical facility. Many products contain several ingredients that could cause problems during anesthesia. These need to be identified so safe anesthesia care can be provided. More research is needed to understand the impact of herbal supplements on anesthesia care, Dr McLeskey said. "As the popularity of herbals continues to grow, so will reports of allergic Demse O'Brlen, BSN, RN, CPAN, CAPA, ts an Educational Nurse Coordtnator/Chmeal Nurse 111 in the PACU/ASU, University of Mwhtgan Health System, Ann Arbor, MI. Condensed from the press releases contained m the ASA me&a kit for the 1999 annual meeting Address correspondence to Demse O'Brlen, BSN, RN, CPAN, CAPA, 8383 Geddes Rd, Ypsllantl, M1 48198-9404; e-mad address, dedeo @umich edu © 2000 by American Society of PerlAnesthesla Nurses 1089-9472/00/1502-0088503 00/0 129

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reactions and adverse drug-herb interactions." Future studies planned by Dr McLeskey's group include a study of the relationship between herbal consumption and coagulation status in surgical patients and to determine herbal consumption in patients seeking therapy for chronic pare conditions. STUDY SHOWS OUTPATIENT SURGERY SAFE FOR THE ELDERLY

Lee A. Fleisher, MD, an anesthesiologist at Johns Hopkins Umversity, reported the results of the first large-scale study on safety of outpatient surgery for the elderly. A total of 150,000 surgeries performed on Medicare patients from 1994 to 1996 were analyzed, evaluating death rates and hospital admission rates caused by complications assooated with a number of common procedures. The procedures were cataract removal, hysterectomy, hernia repair, dilation and curettage, laparoscopic cholecystectomy, and arthroscopy. The findings showed the safety of performing these common procedures in hospital-based outpatient clinics and freestanding surgical centers. Death and hospital admission rates averaged less than 1% for hospital-based outpatient clinics and freestanding surgical centers. However, in patients over 75 years old with coexisting medical conditions mad patients who had been hospitalized during the 6 months before surgery, death and admission rates were higher in all three outpatient settings (hospital, freestanding, and office). According to Dr Flelsher, data on sufficiently large numbers of patients were available for only one type of procedure--cataract removal--in officebased settings. Of interest, complication rates within the first week after cataract surgery was performed in an office were higher than rates for the other 2 types of facilities. This finding warrants further study because office-based settings typically have fewer resources available if complications occur. Dr Fleisher's long-term goal is to identify populations of patients who might benefit from having surgery in facilities with greater resources to deal with emergencies and complications. WRIST DEVICE COMBINES ACUPUNCTURE WITH ELECTRICAL STIMULATION TO CONQUER POSTOPERATIVE NAUSEA

Melinda L. Mingus, MD, an anesthesiologist at Mount Sinai Medical Center, New York, reported

DENISE O'BRIEN on a watch-like device on a patient wrist that is natural, user-friendly, and uses no drugs to treat or prevent postoperative nausea and vomiting (PONV). The lightweight, battery-powered wristband delivers a very low level of electrical current through 2 small electrodes to a forearm acupuncture point. The device blends acupuncture therapy with electrical stimulation. This combination of approaches is known as transcutaneous accupoint electrical stimulation (TAES). It has also been shown effective for motion sickness. The multicenter study presented at the ASA meeting was the first test of TAES for PONV management. The device significantly reduced PONV in a study of 200 patients undergoing laparoscopic cholecystectomy at the University of Texas Southwestern Medical Center, Dallas; Mount Sinai; Wake Forest University; and the University of Southern California-Los Angeles. Patients participating in the study were divided into experimental, placebo, and sham groups. All patients wore wristbands. The experimental group received electrical stimulation to the appropriate acupuncture point. The placebo group wore the device but the electrodes were inactive. The sham group's wristbands were deliberately mispositioned. On a 0 to 7 (none to extreme) nausea scale, participants rated their feelings of nausea at 6 intervals: 45, 90, 120 minutes and 4, 6, and 9 hours. At all intervals except 120 minutes, the patients with TikES reported significantly fewer episodes of nausea and less severe episodes of nausea. Dr Mingus stated, "The devices might have been even more effective if patients had worn them before and during surgery as well as after." ADULT RESPIRATORY DISTRESS SYNDROME PATIENTS BENEFIT FROM NUTRITIONAL SUPPLEMENT

Adult respiratory distress syndrome (ARDS), caused by foreign body inhalation, trauma, or bacterial infection, results in severe pulmonary inflammation and fluid accumulation and major respiratory distress. Sixty to 70% of patients with ARDS die. In a study of 150 patients by researchers at the Mayo Clinic, a 35% reduction in the death rate was achieved in patients that received an experimental treatment: a diet of borage seed oil, fish oil, proteins, carbohydrates, and antioxidants fed

NOTES FROM THE ASA ANNUAL MEETING through a nasogastric tube. Patients receiving the treatment had significantly lower white blood cell counts on analysis of pulmonary fluid samples. Laboratory studies suggest that the benefits are not from the fats or antioxidants but from gammalinolenic acid, a substance found in the oil of the borage seed plant. The researchers, led by anesthesiologist Michael J. Murray, MD, PhD, believed that the compound reduces inflammation, improves oxygen flow and increases the chances of recovery. A second study of 30 patients who consumed the experimental diet also showed significant improvements. In that study, 72% of the ARDS patients on the diet lived but only 22% of patients not on the diet survived. TIMED-RELEASE LOCAL ANESTHETICS COULD LAST FOR DAYS

Currently, postoperative pain relief after the injection of local anesthetics lasts only 4 to 6 hours. Researchers have now created a timed-release form of local anesthetics that could last days instead of hours after surgery. Charles B. Berde, MD, PhD, a professor of anesthesiology and pediatrics at Harvard Medical School reported on a novel approach that allows anesthesiologists to administer an injection that contains microspheres of bupivacaine during operative procedures. "The microspheres would dissolve slowly and steadily and last several days instead of hours," Dr Berde said. This could be especially helpful for pediatric pain management. Microspheres are small, round particles, made up of bupivacaine and some tiny strands of a long-chain molecule (polymer) that is absorbed by the body like dissolvable sutures. Dr Berde suggests that "the medication would be most useful for operations involving the chest, abdomen and other areas that the patient doesn't mind being numb for several days." The new formulation is now being tested in adults and if successful, clinical trials with children could begin within the year. PROSTATECTOMY PROTOCOL SPEEDS RECOVERY AND DISCHARGE

Evelina Worwag, MD, assistant professor of anesthesiology and critical care medicine at the University of Chicago and director of the acute pain service at Weiss Memorial Hospital, reported on a new patient care protocol that uses an old

131 analgesic: methadone. The new protocol for patients undergoing radical retropubic prostatectomy (RRP) allows men to go home only 1 day after surgery. Dr Worwag said, "The new clinical pathway shortens hospital stays, lowers costs, and benefits patients because it reduces pain, minimizes complications, and speeds recovery." The study of 252 men who underwent RRP between 1995 to 1999 showed that 75% of the methadone protocol group returned home the day after surgery. Additional patients met the discharge criteria but chose to stay longer. Ninety-seven percent of the 91% of patients that responded to a follow-up survey expressed satisfaction with their care. Three patients reported complications (1 headache and 2 reports of blood clot retention) that were "directly related" or "probably related" to the protocol. The new protocol uses a combination of regional anesthesia, small doses of methadone, and a complementary pairing of over-the-counter analgesics (acetaminophen and ibuprofen); a focus on ambulation, exercise, and eating soon after surgery; and extensive patient education before and after the procedure. The methadone was injected at the end of the operative procedure and the over-the-counter analgesics were given beginning 4 hours after surgery and continued at home. Patient education is central to the success of the protocol. " I f patients know it is actually better for them to begin walking, eating, and exercising soon after surgery, they are more likely to do so," Dr Worwag said. TELEMEDICINE PROVIDES LONG-DISTANCE CONNECTION

Elderly patients and patients in remote locations often find it difficult to visit hospitals and clinics for preoperative visits. Anesthesiologists at Virginia Mason Medical Center (VMMC) in Seattle, WA have begun using telemedicine to assist in reaching these patients and eliminate day of surgery cancellations owing to Inadequate patient assessment and preparation. Karen J. Roetman, MD, reported that with VMMC's new telemediclne system, the patient will sit in an examination room with a technical assistant at a satellite clinic that may be several miles from the hospital. At VMMC, an anesthesiologist is seated in a room. Both the patient and physician see and hear each other on television monitors.

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Using a key pad, the anesthesiologist can zoom m on a patient's face, mouth, and throat to complete

an airway examination. Difficult airways can be assessed and prepared for using this device. A digital stethoscope can be used to "telemedically" auscultate the patient's heart and lungs. "A number of studies show how important preoperative evaluations are in overall operating room efficiency, and the use of telemedicine mcreases the chances that those evaluations will take place," Dr Roetman said. Day-of-surgery examinations may delay or cancel operative cases because of undetected patient problems. Delays and cancellations add to health care costs. Telemedicine also supports patient education. Dr Roetman said, "Panents handle surgery better when they know what to expect before, during and after their surgery" DOPPLER "RADAR" KEEPS BLOOD FLOWING

Doppler ultrasound may replace invasive line placement for monitoring of cardiac output and fluid volume. The same Doppler technology used to predict the weather can be used to predict potentially hazardous conditions during major surgery. T.J. Gan, MD from Duke University reported substituting a pulmonary artery catheter w~th a catheter with a flexible, pencil-sized Doppler ultrasound probe. After the patient was asleep, the probe was placed in the esophagus near the heart. Continuous display of cardmc output and fired volume was possible with the Doppler probe. Dr Gan's group studied 100 patients, 50 who had surgery with the Doppler probe and 50 who had surgery with routine monitoring. Patients in the Doppler probe group were discharge an average of 2 days earher than the control group. A key difference was the Doppler probe group's ability to eat solid food m 3 days versus 5 days for the control group. Type of surgery did not influence the outcome. "By managing fluid optimally during surgery,

DENISE O'BRIEN we've shown it is possible to reduce length of hospital stay--a difference that translates into conslderable cost savings," Dr Gan said.

MAGNETIC RESONANCE IMAGING USED TO TREAT PAIN

Panents with cancer and nerve injuries suffering from chronic severe pain have a new treatment option: magnetic resonance therapy (MRT), using magnetic resonance imaging that enables anesthesiologists to pinpoint injection sites more accurately. Injected medicaUons or continuous infusion catheters can be placed in specific areas while minimizing damage to surrounding nerves and arteries. The techmque also allows the anesthesiologist to track the injected medications in the body. Sean C. Mackey, MD, PhD, assistant professor of anesthesia and pare management at Stanford University Medical School, said, "MRT's superior imaging capabilities allow us to more safely target the area we want to reach." This technique is particularly useful for patients with tumors that distort normal anatomy and make successful injections more difficult. Pain management specmlists and radiologists working together create MRT's success Dr Mackey reported that in a study of 21 patients, MRT allowed placement of successful regional blocks in every patient without complications. The MRT's system configuration &ffers from the traditional, claustrophobic magnetic resonance imaging design. The patient lays on a table that shdes into the center of 2 doughnut-shaped scanners. The anesthesiologist and radiologist stand between the "doughnuts" and, using video display monitors, adjust the position and trajectory of the needle or catheter. MRT has been used at Stanford to manage pain in patients with pancreatic and other abdominal cancers, complex regional pare syndrome (formerly known as reflex sympatheUc dystrophy or RSD), and traumatic injuries