Rebecca S. Twersky

Practice advisory for preanesthesia evaluation: an updated report by the American Society of Anesthesiologists Task Force on Preanesthesia Evaluation.

P RACTICE Advisories are systematically developed reports that are intended to assist decision-making in areas of patient care. Advisories provide a synthesis and analysis of expert opinion, clinical feasibility data, open forum commentary, and consensus surveys. Practice Advisories developed by the American Society of Anesthesiologists (ASA) are not intended as standards, guidelines, or absolute requirements, and their use cannot guarantee any specific outcome. They may be adopted, modified, or rejected according to clinical needs and constraints and are not intended to replace local institutional policies. Practice Advisories are not supported by scientific literature to the same degree as standards or guidelines because of the lack of sufficient numbers of adequately controlled studies. Practice Advisories are subject to periodic update or re-

Society for Ambulatory Anesthesia consensus statement on perioperative blood glucose management in diabetic patients undergoing ambulatory surgery.

Optimal evidence-based perioperative blood glucose control in patients undergoing ambulatory surgical procedures remains controversial. Therefore, the Society for Ambulatory Anesthesia has developed a consensus statement on perioperative glycemic management in patients undergoing ambulatory surgery. A systematic review of the literature was conducted according the protocol recommended by the Cochrane Collaboration. The consensus panel used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system for providing suggestions. It was revealed that there is insufficient evidence to provide strong recommendations for the posed clinical questions. In the absence of high-quality evidence, recommendations were based on general principles of blood glucose control in diabetics, drug pharmacology, and data from inpatient surgical population, as well as clinical experience and judgment. In addition, areas of further research were also identified.

What happens after discharge? Return hospital visits after ambulatory surgery.

The purpose of this study was to examine the frequency of return hospital visits after ambulatory surgery discharge and to identify any predictor variables for its occurrence.A retrospective review of hospital records for all patients returning to the same hospital within 30 days after ambulatory surgery was conducted. Data on return hospital visits that resulted in rehospitalization (as an inpatient or to the ambulatory surgery unit [ASU]) or treatment as an outpatient in the emergency room were recorded. A total of 6243 patients underwent ambulatory surgery over 12 consecutive months and 187 returned to the same hospital of which 1.3% were for complications. Of all the returns, 54% returned to the emergency room (ER) and 46% were rehospitalized as inpatients or to ASU. To identify factors associated with an increased likelihood of return, two case controls for each return visit were obtained from medical records of ambulatory surgical patients operated on during the same time period. Results of the multivariate analysis on the matched case controls identified urology as the only significant surgical service that predicted returns. (Odds ratio 27.87; confidence interval [CI] 3.78-74.86; P = 0.0002). A separate analysis of the most common ASU procedures performed identified two surgical procedures that predicted hospital return as compared with overall ambulatory surgery population: patients undergoing varicocelectomy and hydrocelectomy procedures were 8.3 times more likely to return (CI 2.090-23.75; P = 0.0042); patients undergoing dilation and curettage were three times as likely to return (CI 1.78-5.55; P = 0.0002). Bleeding was the most common reason for all hospital returns (41.5%), with 76.5% of these patients treated and discharged through the ER. The increased likelihood of return visits after urology procedures warrants further evaluation. As patients with bleeding were most likely to return to the ER and discharged, more effective pre- and postprocedure patient education may further reduce this occurrence. Better informing patients regarding the prognosis of bleeding, and advising them of medical alternatives, could reduce inappropriate patient returns to the ER. (Anesth Analg 1997;84:319-24)

Midazolam Enhances Anterograde but not Retrograde Amnesia in Pediatric Patients

BackgroundMidazolam sedation has been shown to diminish recall of one to four cards shown prior to induction of general anesthesia in pediatric patients. This promising but limited finding prompted us to investigate the effect of midazolam sedation on retrograde and anterograde recall and recognition in children scheduled for elective surgery. MethodsForty patients aged 4–10 yr were randomized using a double-blind study design to receive either 0.2 mg/kg intranasal midazolam or 0.2 ml/5 kg placebo (distilled water) using a Devilbiss #286 atomizer. To assess postoperative memory of preoperative events, recall and recognition tasks were performed using a series of picture cards designed for this purpose. Retrograde amnesia was measured by postoperative recall and recognition of cards shown prior to midazolam/placebo administration, and anterograde amnesia was measured by postoperative recall and recognition of cards shown during the interval between midazolam/placebo administration and induction of general anesthesia. ResultsCompared to placebo, the midazolam group experienced a significant postoperative reduction in ability to both recall (P <.003) and recognize (P <.001) cards shown subsequent to midazolam/placebo administration (anterograde amnesia). In distinction, there was no difference between groups in postoperative ability to recall or recognize cards shown prior to midazolam/placebo administration (retrograde amnesia). ConclusionsThese results support and extend the inference that midazolam diminishes anterograde recall. In addition, our findings indicate that midazolam diminishes anterograde recognition, thereby providing partial anterograde amnesia without affecting retrograde memory in pediatric patients.

A comparison of the remifentanil and fentanyl adverse effect profile in a multicenter phase IV study

STUDY OBJECTIVE To compare the frequency of adverse effects of remifentanil and fentanyl in a large and diverse patient population. DESIGN Prospective, randomized, open-label study. SETTING Multicenter study including academic and community hospitals. PATIENTS 2,438 adult patients (1,496 outpatients and 942 inpatients) scheduled for elective surgical procedures under general endotracheal anesthesia of at least 30-minute duration. INTERVENTIONS Patients were randomly assigned to receive either intravenous (IV) remifentanil (n = 1,229) 0.5 microg/kg/min for induction and tracheal intubation followed by an infusion rate of 0.25 microg/kg/min or fentanyl (n = 1,209) administered according to the anesthesiologists usual practice. Anesthesia was maintained with propofol and/or isoflurane (with or without nitrous oxide) titrated according to protocol. Transition analgesia with either morphine or fentanyl was administered in the remifentanil and, at the anesthesiologists discretion, in the fentanyl group. MEASUREMENTS The overall nonspecific and specific (i.e., opioid-related) adverse effects were recorded. MAIN RESULTS Remifentanil was associated with more intraoperative hypotension than fentanyl (p < 0.05). All four cases (0.3%) of muscle rigidity occurred in the remifentanil-treated outpatients. There were no significant differences between the two drugs with respect to other adverse events (i.e., episodes of hypertension, bradycardia, respiratory depression, and apnea). CONCLUSIONS In the doses used, both remifentanil and fentanyl have a similar frequency of adverse effects except for the higher frequency of hypotension associated with the use of remifentanil.

Anesthesia Induction Using Video Glasses as a Distraction Tool for the Management of Preoperative Anxiety in Children

BACKGROUND: Distraction technology suitable for the perioperative setting is readily available, but there is little evidence to show how it compares with oral midazolam in managing anxiety. Video glasses, which enable children to view and listen to cartoons and movies, may be used through the completion of inhaled induction. We compared the efficacy of oral midazolam and behavioral distraction with video glasses in managing preoperative anxiety in children. METHODS: In this prospective, randomized study, 96 children aged 4 to 9 years undergoing outpatient surgery were recruited to one of 3 intervention groups receiving midazolam, video glasses, or both. The Modified Yale Preoperative Anxiety Scale was the primary dependent measure used to assess anxiety at baseline before intervention, 20 minutes later at transport to the operating room (OR), and during mask induction. RESULTS: There was no significant increase in anxiety score within any group between baseline and OR transport (P = 0.21, 0.42, and 0.57 for midazolam, video glasses, and combined groups, respectively). An increase in anxiety, though not large enough to be clinically significant, was observed from baseline to induction in the midazolam and combined groups (P = 0.02 and 0.03) but not in the video glasses group (P = 0.38). Confidence intervals for pairwise comparisons in Modified Yale Preoperative Anxiety Scale changes among groups were all within a clinically significant difference of 15 units. CONCLUSIONS: The use of video glasses and midazolam alone or in combination maintains baseline levels of anxiety at time of transport to the OR and prevents significantly increased anxiety during induction of anesthesia in children. Video glasses are not inferior to midazolam for preoperative anxiolysis and provide a safe, noninvasive, nonpharmacologic, and pleasant alternative.

Fast tracking in ambulatory surgery

Fast tracking after ambulatory surgery is a new paradigm which involves transferring patients from the operating room to the phase II recovery unit (i.e. bypassing the postanaesthesia care unit). The success of fast tracking depends upon appropriate modification of the anaesthetic technique, which would allow rapid emergence from anaesthesia, and the prevention of common postoperative complications such as pain, nausea and vomiting using a multimodal approach. Implementation of a fast track program involves use of clinical pathways that would reduce hospital stay and ensure patient safety. Finally, the concept of fast tracking should be expanded to the overall postoperative recovery, not just bypassing the postanaesthesia care unit.

Neuroleptic malignant syndrome.

In recent years a substantial number of malignant hyperthermia (MH) cases have been reported (1). At the same time over 60 cases of neuroleptic malignant syndrome (NMS) have been presented in the psychiatric literature (2). The similarity of clinical and physiologic features among MH, NMS, and other hypermetabolic syndromes have prompted many investigators to hypothesize a common pathophysiologic mechanism (1-3). We recently anesthetized a patient diagnosed as having NMS whose clinical and laboratory picture resembled that of a patient with MH .

Office-Based Anesthesia: How to Start an Office-Based Practice

Ambulatory, office-based anesthesia (OBA) has experienced an exponential growth in the last decade, and is popular among patients and health care providers alike. About 17% to 24% of all elective ambulatory procedures in the United States are currently being performed in an office-based setting. Special considerations must be made when comparing OBA to a hospital setting, particularly with respect to facility and environment, administration, and accreditation. Increasing regulation will ensure that patient safety remains the primary focus. In the meantime, the anesthesia provider must take adequate steps to ensure that the quality of care in OBA is comparable to that in a hospital.

Office-based anesthesia: safety and outcomes

The increasing volume of office-based medical and surgical procedures has fostered the emergence of office-based anesthesia (OBA), a subspecialty within ambulatory anesthesia. The growth of OBA has been facilitated by numerous trends, including innovations in medical and surgical procedures and anesthetic drugs, as well as improved provider reimbursement and greater convenience for patients. There is a lack of randomized controlled trials to determine how office-based procedures and anesthesia affect patient morbidity and mortality. As a result, studies on this topic are retrospective in nature. Some of the early literature broaches concerns about the safety of office-based procedures and anesthesia. However, more recent data have shown that care in ambulatory settings is comparable to hospitals and ambulatory surgery centers, especially when offices are accredited and their proceduralists are board-certified. Office-based suites can continue to enhance the quality of care that they deliver to patients by engaging in proper procedure and patient selection, provider credentialing, facility accreditation, and incorporating patient safety checklists and professional society guidelines into practice. These strategies aiming at patient morbidity and mortality in the office setting will be increasingly important as more states, and possibly the federal government, exercise regulatory authority over the ambulatory setting. We explore these trends, their implications for patient safety, strategies for minimizing patient complications and mortality in OBA, and future developments that could impact the field.