Airway responses to desflurane during maintenance of anesthesia and recovery in children with laryngeal mask airways.

BACKGROUND: We sought to characterize the airway responses to desflurane during maintenance of and emergence from anesthesia in children whose airways were supported with laryngeal mask airways (LMAs). METHODS/MATERIALS: Four hundred healthy children were randomized in a 3 : 1 ratio to either desflurane or isoflurane (reference group) during anesthetic maintenance. After induction of anesthesia, anesthesia was maintained with the designated anesthetic. The investigator chose the airway (LMA and facemask), ventilation strategy and when to remove the LMA. The incidence of airway events during maintenance, emergence and recovery was recorded. RESULTS: Ninety percent of children received LMAs. The frequency of major airway events after desflurane (9%) was similar to that after isoflurane (4%) (number needed to harm [NNH] 20), although the frequency of major events after the LMA was removed during deep desflurane anesthesia (15%) was greater than during awake removal (5%) (NNH 10) (P < 0.006) and during deep isoflurane removal (2%) (NNH 8) (P < 0.03). The frequency of airway events of any severity after desflurane was greater than that after isoflurane (39% vs 27%) (P < 0.05). The frequencies of laryngospasm and coughing of any severity after desflurane were greater than those after isoflurane (13% vs 5% and 26% vs 14%, respectively) (P < 0.05). CONCLUSIONS: When an LMA is used during desflurane anesthesia in children, fewer airway events occur when it is removed when the child is awake. Although the time to discharge from recovery was not delayed and no child required overnight admission, caution should be exercised when using an LMA in children who are anesthetized with desflurane.

Should I get a Master of Business Administration? The anesthesiologist with education training: training options and professional opportunities.

PURPOSE OF REVIEW: Many physicians want to know whether they should get a Master of Business Administration (MBA), what type of program is best, and what career paths exist. RECENT FINDINGS: It is commonly (incorrectly) assumed that a physician successful in clinical practice can easily transfer to managing/leading an organization. To be effective, the MD/MBA must bridge the cultures of the business world and medicine. Often just a single management course is sufficient to give the physician the knowledge they seek. MBA programs come in many forms and require choosing from a range of time commitments. Leaving a good clinical job in favor of the less-defined course of an MD/MBA can be daunting. Although a wide spectrum of opportunities are available, the MD/MBA may have to start over professionally, most likely with a pay cut, and will have to 'work their way up' again. A stigma exists for MD/MBAs because they are often perceived as caring more about business than about patients. Many MD/MBAs eventually choose to stay in full-time medical practice because financial and geographic stability may be more easily attained. SUMMARY: The MBA is a good idea for the physicians who enjoy the intellectual challenges of business administration and proactively plan their own career.

Intravenous emulsified halogenated anesthetics produce acute and delayed preconditioning against myocardial infarction in rabbits.

BACKGROUND: Preconditioning against myocardial infarction by volatile anesthetics is well known. The authors tested the hypothesis that new emulsified formulations of halogenated anesthetics administered intravenously reduce myocardial infarct size when administered either 1 or 24 h before prolonged ischemia and reperfusion. METHODS: Pentobarbital-anesthetized rabbits (n = 39) were instrumented for measurement of hemodynamics and randomly assigned to receive intravenous saline (control), lipid vehicle, or infusions (3.5 ml . kg . h for 30 min) of emulsified isoflurane (6.9%), enflurane (7.1%), or sevoflurane (7.5%). Infusions were discontinued 30 min before a 30-min coronary occlusion and 3 h of reperfusion. In three additional groups, conscious rabbits (n = 21) received saline, lipid vehicle, or emulsified sevoflurane (7.5%) infusions (3.5 ml . kg . h for 30 min) 24 h before ischemia and reperfusion. Infarct size was determined using triphenyltetrazolium staining. RESULTS: Lipid vehicle produced transient increases in heart rate, whereas emulsified volatile anesthetics had no effect on hemodynamics before coronary occlusion. Lipid vehicle did not affect infarct size (38 +/- 2% of the area at risk; mean +/- SEM) as compared with saline control (41 +/- 4%). In contrast, emulsified isoflurane, enflurane, and sevoflurane reduced infarct size (20 +/- 3%, 20 +/- 3%, and 21 +/- 2% of the area at risk, respectively; P < 0.05). Administration of lipid vehicle or emulsified sevoflurane did not produce sedation or respiratory depression in conscious rabbits. Emulsified sevoflurane (18 +/- 2%) but not lipid vehicle (44 +/- 2%) reduced infarct size as compared with control in delayed preconditioning experiments. CONCLUSIONS: Intravenous emulsified halogenated anesthetics produce acute and delayed preconditioning against myocardial infarction.

The comparative effects of desflurane and isoflurane on lumbar cerebrospinal fluid pressure in patients undergoing craniotomy for supratentorial tumors.

UNLABELLED: We compared the effects of desflurane and isoflurane on cerebral perfusion pressure (CPP), lumbar cerebrospinal fluid pressure (LCSFP), and mean arterial blood pressure (MAP) in patients anesthetized with desflurane or isoflurane undergoing craniotomy for supratentorial mass lesions. Additionally, emergence from anesthesia was examined to determine if neurologic function could be assessed earlier after isoflurane or desflurane anesthesia. Thirty-six patients were randomized to receive either desflurane or isoflurane for maintenance of anesthesia at 1.2 minimum alveolar concentration (MAC). Patients were hyperventilated (PaCO(2), 30 +/- 2 mm Hg) after baseline LCSFP was obtained via the subarachnoid catheter. At a MAC of 1.2, mean LCSFP was not statistically different between the two study groups either before or after hyperventilation. Additionally, CPP was not significantly different between the two groups. Finally, patient's time to respond to commands was 50% shorter in the desflurane group (30 +/- 36 min) (mean +/- SD) when compared with the isoflurane group (72 +/- 126 min); however, this was not significant (P = 0.17). In patients undergoing craniotomy for supratentorial mass lesions, desflurane and isoflurane have similar effects on CPP and MAP. Additionally, desflurane in the setting of hyperventilation does not cause significant changes in LCSFP. IMPLICATIONS: This is the largest study to date comparing the effects of desflurane and isoflurane on patients undergoing craniotomy for supratentorial mass lesion with evidence of midline shift or edema. Neither desflurane nor isoflurane significantly altered lumbar cerebrospinal fluid pressure when moderate hypocapnia was maintained.

Esmolol in acute ischemic syndromes.

BACKGROUND: beta-Blockers have been shown to reduce both morbidity and mortality rates in patients with acute coronary syndromes. However, because of potential side effects, their use is limited in patients who might benefit the most from such therapy. It was thought that the use of an ultra-short-acting intravenous beta-blocker might produce similar results with fewer complications in those patients with relative contraindications to beta-blocker therapy. METHODS: Accordingly, we evaluated the use of esmolol in patients with acute coronary syndromes and relative contraindication to beta-blocker therapy in a prospective randomized trial. One hundred eight patients at 21 sites received an infusion of intravenous esmolol or standard therapy on admission and were followed for 6 weeks from the day of admission. The primary efficacy outcome was a composite event consisting of any of the following that occurred during the index hospitalization: death, myocardial (re)infarction, recurrent ischemia, or arrhythmia as well as silent myocardial ischemia assessed by ambulatory electrocardiographic monitoring. Safety end points including hypotension, bradyarrhythmias, new or worsening congestive heart failure, and bronchospasm were also recorded. RESULTS: Event rates for primary end points were similar in the 2 groups: death (2% in the standard care group vs 4% in the group receiving esmolol), myocardial (re)infarction (4% standard vs 7% esmolol), ischemia (12% vs 13%), arrhythmias (4% vs 2%), and silent ischemia (13% vs 15%). There was a higher incidence of transient hypotension in the group receiving esmolol (2% vs 16%), but all such events were noted to resolve after discontinuation of the esmolol infusion. There were no additional differences in safety end points: bradycardia (2% for those receiving standard care vs 9% receiving esmolol), new congestive heart failure (10% vs 16%), bronchospasm (0% vs 7%), and heart block (2% vs 2%). CONCLUSIONS: The use of an ultra-short-acting beta-blocker such as esmolol might offer an alternative to patients with contraindications to standard beta-blocker therapy. Although this trial had limited power to detect safety and efficacy differences between the 2 therapies, it was observed that safety end points, which occurred during esmolol administration, resolved readily when the infusions were decreased or discontinued. Additional testing is needed to substantiate these findings.