Anesthesia and analgesia
-
Anesthesia and analgesia · Oct 2013
Rescheduling of Previously Cancelled Surgical Cases Does Not Increase Variability in Operating Room Workload When Cases Are Scheduled Based on Maximizing Efficiency of Use of Operating Room Time.
Conceptually, cancelling a case close to the scheduled day of surgery increases variability in operating room (OR) workload (i.e., total hours of scheduled cases plus turnovers), creating managerial problems. However, in our recent study of an OR scheduling office, cancellations (slightly) reduced variability in workload among days. If a relatively low incidence of cancellations does not cause increased variability in workload, this would be a useful finding when focusing strategic OR management initiatives. However, the previous study considered only the effect on the schedule for the day the cancelled case originally was scheduled to be performed, not the future date on which the case was performed. ⋯ Rescheduled cancelled cases did not increase variability in OR workload. This finding is useful combined with our recent finding that cancellation slightly reduces variability in OR workload on the date of cancellation. Cancellations should not be interpreted as a system failure that increases variability in surgical workload. We recommend that anesthesiologists aim to reduce cancellation rates if above benchmarked averages, but otherwise focus on more strategically beneficial initiatives. We recommend also that these results be considered if cancellation rates are used in assessing anesthesiology group performance.
-
Anesthesia and analgesia · Oct 2013
ReviewUnderstanding the Mechanism: Mediation Analysis in Randomized and Nonrandomized Studies.
In comparative clinical studies, a common goal is to assess whether an exposure, or intervention, affects the outcome of interest. However, just as important is to understand the mechanism(s) for how the intervention affects outcome. For example, if preoperative anemia was shown to increase the risk of postoperative complications by 15%, it would be important to quantify how much of that effect was due to patients receiving intraoperative transfusions. ⋯ We discuss the proper design and analysis of studies investigating mediation, including the importance of distinguishing mediator variables from confounding variables, the challenge of identifying potential mediators when the exposure is chronic versus acute, and the requirements for claiming mediation. Simple designs are considered, as well as those containing multiple mediators, multiple outcomes, and mixed data types. Methods are illustrated with data collected by the National Surgical Quality Improvement Project (NSQIP) and utilized in a companion paper which assessed the effects of preoperative anemic status on postoperative outcomes.
-
Anesthesia and analgesia · Oct 2013
Biography Historical ArticleThomas Linwood Bennett, MD: One of New York City's First Prominent Physician Anesthetists.
Thomas Linwood Bennett (1868-1932) was one of New York City's first prominent physician anesthetists. He was the first dedicated anesthetist at the Hospital for the Ruptured and Crippled, subsequently renamed Hospital for Special Surgery. He subsequently practiced at multiple institutions throughout New York City as one of the first physicians in the United States to dedicate his entire practice to the emerging field of anesthesia. Bennett was considered the preeminent anesthetist of his time, excelling at research, innovation, education, and clinical care.
-
Anesthesia and analgesia · Oct 2013
ReviewReduction of Myocardial Infarct Size with Ischemic "Conditioning": Physiologic and Technical Considerations.
A wealth of evidence has revealed that the heart can be "conditioned" and rendered less vulnerable to ischemia-reperfusion injury via the upregulation of endogenous protective signaling pathways. Three distinct conditioning strategies have been identified: (1) preconditioning, the phenomenon where brief episodes of myocardial ischemia (too brief to cause cardiomyocyte death) limit necrosis caused by a subsequent sustained ischemic insult; (2) postconditioning, the concept that relief of myocardial ischemia in a staged or stuttered manner attenuates lethal ischemia-reperfusion injury; and (3) remote conditioning, or upregulation of a cardioprotective phenotype initiated by ischemia in a remote organ or tissue and "transported" to the heart. ⋯ There is, however, a potentially important caveat to the clinical translation of myocardial conditioning: emerging data suggest that the efficacy of ischemic conditioning is compromised in aging, diabetic, and hypertensive cohorts, the specific populations in which myocardial protection is most relevant. Successful clinical application of myocardial conditioning will therefore require an understanding of the potential confounding consequences of these comorbidities on the "conditioned" phenotype.