Perioperative management of obstructive sleep apnea in bariatric surgery: a consensus guideline.

BACKGROUND: The frequency of metabolic and bariatric surgery (MBS) is increasing worldwide, with over 500,000 cases performed every year. Obstructive sleep apnea (OSA) is present in 35%-94% of MBS patients. Nevertheless, consensus regarding the perioperative management of OSA in MBS patients is not established. OBJECTIVES: To provide consensus based guidelines utilizing current literature and, when in the absence of supporting clinical data, expert opinion by organizing a consensus meeting of experts from relevant specialties. SETTING: The meeting was held in Amsterdam, the Netherlands. METHODS: A panel of 15 international experts identified 75 questions covering preoperative screening, treatment, postoperative monitoring, anesthetic care and follow-up. Six researchers reviewed the literature systematically. During this meeting, the "Amsterdam Delphi Method" was utilized including controlled acquisition of feedback, aggregation of responses and iteration. RESULTS: Recommendations or statements were provided for 58 questions. In the judgment of the experts, 17 questions provided no additional useful information and it was agreed to exclude them. With the exception of 3 recommendations (64%, 66%, and 66% respectively), consensus (>70%) was reached for 55 statements and recommendations. Several highlights: polysomnography is the gold standard for diagnosing OSA; continuous positive airway pressure is recommended for all patients with moderate and severe OSA; OSA patients should be continuously monitored with pulse oximetry in the early postoperative period; perioperative usage of sedatives and opioids should be minimized. CONCLUSION: This first international expert meeting provided 58 statements and recommendations for a clinical consensus guideline regarding the perioperative management of OSA patients undergoing MBS.

Acute pain management in morbid obesity - an evidence based clinical update.

Increasing numbers of patients with morbid obesity are presenting for surgery and their acute pain management requires an evidence-based clinical update. The objective of this study was to complete a literature review for acute pain management in morbid obesity and provide an evidence-based clinical update with recommendations. Using standardized search terms, in March 2015, we completed a literature search to determine evidence for different acute pain pharmacological modalities in morbid obesity. For each modality the highest level of evidence was ascertained and recommendations for each pharmacological modality are presented. Though overall evidence is limited to few well conducted clinical trials, mostly related to weight loss surgery, multimodal analgesia with step-wise, severity-based, opioid-sparing approach appears to improve acute pain management in morbid obesity. The perioperative use of non-opioid adjuvants appears to offer further improvements in patient safety and outcomes. Further research into standardization of pain assessments and implementation of acute pain management protocols is required.

Designing intelligent anesthesia for a changing patient demographic: a consensus statement to provide guidance for specialist and non-specialist anesthetists written by members of and endorsed by the Society for Obesity and Bariatric Anaesthesia (SOBA).

BACKGROUND: As a result of the increasing prevalence of obesity in the UK, anesthetists are increasingly encountering overweight and obese patients in routine practice. There is currently a paucity of evidence to guide best clinical practice for anesthetists managing overweight and obese patients. The current guidelines from the Association of Anaesthetists of Great Britain and Ireland (AAGBI), entitled Peri-Operative Management of the Morbidly Obese Patient, give an excellent overview of organizational issues, but leave much clinical detail to the discretion of the individual clinician. METHODS: In May 2010, a panel of experts convened to develop consensus on anesthesia of overweight, obese and morbidly obese patients, in consultation with the Society for Obesity and Bariatric Anaesthesia (SOBA). All Panel members are practicing clinicians from recognized bariatric surgical training centers and have extensive experience of anesthesia for obese patients. This statement aims to provide guiding principles on best practice for this challenging patient demographic, and to increase awareness of current issues so that these can be addressed more appropriately. RESULTS: In this document, we emphasize key principles for best practice, rather than giving prescriptive guidance and specific regimens for all clinical eventualities. We provide evidence-based justification for best-practice techniques, where this exists. In areas for which there is no evidence, but there is clear consensus, we offer this as guidance. We also aim to dispel misconceptions that have arisen in the anesthetic practice of overweight, obese, and morbidly obese patients. CONCLUSION: Ultimately, the choice of specific technique depends on clinician experience, patient characteristics, and center facilities. As well as providing guiding principles for anesthesia, this consensus statement also highlights other areas where anesthetists can contribute towards the enhanced recovery and overall quality of patient care.

Plasma volume measurement in septic patients using an albumin dilution technique: comparison with the standard radio-labelled albumin method.

OBJECTIVE: To investigate a technique using 20% albumin for measurement of plasma volume in critically ill patients. DESIGN AND SETTING: Laboratory and clinical investigation in the adult intensive care unit and anaesthetic laboratories of a university hospital. PATIENTS: 12 patients fulfilling ACCP/SCCM criteria for septic shock. INTERVENTIONS AND MEASUREMENTS: Each patient received (125)I-labelled albumin, and the volume of distribution was measured at 1 and 10 min. The accepted standard plasma volume measurement (98% of the 10-min volume of distribution) was calculated. Immediately thereafter 200 ml 20% human albumin was given. Albumin concentrations were measured before and 1 min after this 40-g bolus, and the volume of distribution calculated using a formula that corrected for the 200 ml fluid in which the albumin was dissolved. RESULTS: Plasma volumes measured using the albumin dilution technique at 1 min were smaller than the standard technique by 110+/-280 ml; limits of agreement were from -660 to +440 ml (-16% to +11%). Plasma volumes measured by (125)I-albumin at 1 min were smaller than the standard by 120+/-110 ml; limits of agreement were from -330 to +100 ml (-8 to +2%). CONCLUSIONS: Non-labelled albumin can be used easily and quickly to measure a plasma volume in ICU patients and gives a moderately accurate estimate when compared with the (125)I-labelled albumin methods. The normal isotope method over-estimates plasma volumes in septic patients because excessive transcapillary escape of albumin is inadequately compensated for by the standard correction factor.

Effects of albumin supplementation on microvascular permeability in septic patients.

Albumin has a stabilizing effect on endothelium and helps maintain capillary permeability to macromolecules. Critically ill patients with sepsis may have profound hypoalbuminemia, but the effect of this hypoalbuminemia on microvascular permeability is unknown. To determine the degree and potential importance of this effect, we measured the transcapillary escape rate (TER) of (125)I-labeled albumin in 12 adult patients fulfilling American College of Chest Physicians/Society of Critical Care Medicine criteria for septic shock. We measured TER over a 90-min baseline period and then repeated these measurements immediately after the rapid infusion of 200 ml of 20% albumin. At baseline, patients had a mean serum albumin concentration of 10.3 +/- 3.8 g/l, which, at 30 min after the albumin infusion, was 18.5 +/- 3.7 g/l. The baseline TER was 6.7 +/- 1.5%/h, with a postinfusion TER of 6.4 +/- 2.1%/h (P = 0.550). Albumin supplementation sufficient to nearly double serum concentrations in profoundly hypoalbuminemic septic patients had no clinically significant effect in reducing microvascular permeability.