Pharmacological Approach for the Prevention of Postoperative Shivering: A Systematic Review of Prospective Randomized Controlled Trials.

Shivering is a common postoperative complication that occurs after both general and regional anesthesia even in the cases when hypothermia during surgery has been averted. Patients describe it as a highly unpleasant experience, while clinicians are concerned due to its adverse effects such as increased oxygen consumption. In this article, we present a summary of the pathophysiological mechanisms involved in postoperative shivering (POS), risk factors, and inadvertent effects. The major objective of this article was to review the existing literature on the effi ciency of various drug interventions as a prophylactic measure against POS. Since α2-adrenergic, opioid, anticholinergic, and serotonergic pathways are thought to play a role in the pathogenesis of POS, a wide variety of drugs has been investigated in this regard. Although the methodological diversity of the study designs and regimens does not support drawing defi nite conclusions, there is evidence indicating a benefi cial effect of dexmedetomidine, ketamine, tramadol, meperidine, dexamethasone, nefopam, granisetron, and ondansetron in the prevention of POS. The purpose of this review is to provide a thorough insight on various drug options and to serve as an aid for clinicians for careful analysis of the advantages and disadvantages of each regimen to decide which regimen will be ideally suited for the medical profi le of each patient

Anesthesia Related Toxic Effects on In Vitro Fertilization Outcome: Burden of Proof

Management of pain and anxiety during oocyte retrieval makes anesthesia an important part of the in vitro fertilization (IVF) procedures. There are many studies investigating the influence of anesthesia on IVF success. This review article provides an overview of published data regarding the potential toxic effects of different anesthetic techniques (Loco-regional, general anesthesia (GA), and monitored anesthesia care (MAC)), different anesthetic agents, and alternative medicine approach (principally acupuncture) on the IVF outcome. From our analysis, evidence of serious toxicity in humans is not well established. Trials regarding different anesthetic techniques ended up without clear conclusions. Studies about GA came up with conflicting results. A few trials relate GA with lower pregnancy rates, although some others failed to prove this conclusion. Furthermore, detectable amounts of some anesthetic agents are measurable in the follicular fluid but these findings are not strongly associated with toxicity. MAC and Loco-regional anesthesia appear as safe alternative choices and there is evidence of improved outcome. Whereas acupuncture may provide assistance increasing IVF success according to some trials, some others could not obtain these effects. Questions about the appropriate time of application and the underlying mechanism of action are not answered yet, so further investigation should be done

No change in serum melatonin, or plasma beta-endorphin levels after sevoflurane anesthesia

Study objective: To investigate the effect of sevoflurane as single anesthetic on melatonin and beta-endorphin plasma levels during the first 24 hours postoperatively. Design: Prospective, open-cohort study. Setting: University hospital. Patients: 13 ASA physical status I and II adults, scheduled for dilatation and curettage of the uterus, and 13 healthy volunteers. Interventions: Patients received general anesthesia with sevoflurane. Measurements: Metatonin and beta-endorphin plasma levels were determined before anesthesia, immediately after, and two, 4, 8, and 24 hours after the end of anesthesia. Melatonin and beta-endorphin were also measured in 13 healthy subjects (controls) not undergoing anesthesia at similar times during the day. Systolic and diastolic blood pressure, heart rate, bispectral index, and oxygen saturation via pulse oximeter (SpO(2)) were recorded before and after anesthesia. Quality of sleep postoperatively was also assessed. Main results: Melatonin levels (pg/mL) in patients and controls were 8.2 +/- 7.9 versus 15.2 +/- 15.0 before anesthesia and 7.7 +/- 7.9 versus 11.1 +/- 7.0, 6.5 +/- 6.1 versus 15.6 +/- 16.3, and 19.5 +/- 17.9 versus 23.7 +/- 23.3 at the end of anesthesia and 4 and 24 hours after the end of anesthesia, respectively (P = 0.057). At the same time points, beta-endorphin plasma levels (pmol/L) in patients and controls were 5.2 +/- 2.0 versus 4.0 +/- 2.3, 5.4 +/- 3.3 versus 3.9 +/- 2.5, 4.9 +/- 1.2 versus 4.4 +/- 1.7, and 3.7 +/- 2.6 versus 4.2 +/- 1.8, respectively (P = 0.285). The quality of sleep assessed clinically was not altered. Conclusion: Sevoflurane as a single anesthetic for minor gynecological procedures did not influence significantly melatonin or beta-endorphin plasina levels. Sleep quality assessed clinically was not influenced. (c) 2007 Elsevier Inc. All rights reserved