Unravelling the analgesic effects of perioperative magnesium in general abdominal surgery: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Prior research has established the effectiveness of magnesium in relieving postoperative pain. This article aims to evaluate magnesium sulfate for perioperative analgesia in adults undergoing general abdominal surgery under general anesthesia. OBJECTIVE: The primary aim was to assess pain scores at 6 and 24 hours postoperatively in patients receiving magnesium sulfate vs. the control group. Secondary outcomes were postoperative opioid consumption, perioperative complications, and time to rescue analgesia. METHODS: A comprehensive database search identified studies comparing magnesium sulfate with control in adults undergoing general anesthesia for general abdominal surgery. Using random-effects models, data were presented as mean ± Standard Deviation (SD) or Odds Ratios (OR) with corresponding 95% Confidence Intervals (95% CI). A two-sided p-value < 0.05 was considered statistically significant. RESULTS: In total, 31 studies involving 1762 participants met the inclusion criteria. The magnesium group showed significantly lower postoperative pain scores at both early (within six hours) and late (up to 24 hours) time points compared to the control group. The early mean score was 3.1 ± 1.4 vs. 4.2 ± 2.3, and the late mean score was 2.3 ± 1.1 vs. 2.7 ± 1.5, resulting in an overall Mean Difference (MD) of -0.72; 95% CI -0.99, -0.44; p < 0.00001. The magnesium group was associated with lower rates of postoperative opioid consumption and shivering and had a longer time to first analgesia administration compared to the saline control group. CONCLUSION: Magnesium sulfate administration was linked to reduced postoperative pain and opioid consumption following general abdominal surgery.

Comparison of Different Weight Scalars to Dose Sugammadex for the Reversal of Neuromuscular Blockade in Morbidly Obese Patients: A Systematic Review.

This systematic review was conducted to evaluate the optimal weight scalar to dose sugammadex in a morbidly obese (MO) patient population (BMI≥40 kg/m2). The primary outcome was recovery time from moderate neuromuscular blockade (NMB) or deep NMB. Secondary outcomes included time to extubation and incidence of postoperative residual curarization (PORC). Eight randomized controlled trials (RCTs) involving 645 participants were included. The different dose scalars included were total body weight (TBW), ideal body weight (IBW), 20% corrected body weight (CBW) and 40% CBW). A dose of 2 mg/kg of sugammadex based on 40% CBW and a 4 mg/kg dose of sugammadex based on 40% CBW provide a reliable and timely reversal of moderate and deep NMB respectively in the MO patients.

Guidelines to the Practice of Anesthesia-Revised Edition 2024.

OVERVIEW: The Guidelines to the Practice of Anesthesia-Revised Edition 2024 (the Guidelines) were prepared by the Canadian Anesthesiologists' Society (CAS), which reserves the right to determine their publication and distribution. The Guidelines are subject to revision and updated versions are published annually. The Guidelines to the Practice of Anesthesia-Revised Edition 2024 supersede all previously published versions of this document. Although the CAS encourages Canadian anesthesiologists to adhere to its practice guidelines to ensure high-quality patient care, the CAS cannot guarantee any specific patient outcome. Anesthesiologists should exercise their own professional judgement in determining the proper course of action for any patient's circumstances. The CAS assumes no responsibility or liability for any error or omission arising from the use of any information contained in its Guidelines to the Practice of Anesthesia.

RéSUMé: Le Guide d'exercice de l'anesthésie, version révisée 2024 (le Guide), a été préparé par la Société canadienne des anesthésiologistes (SCA), qui se réserve le droit de décider des termes de sa publication et de sa diffusion. Le Guide est soumis à révision et des versions mises à jour sont publiées chaque année. Le Guide d'exercice de l'anesthésie, version révisée 2024, remplace toutes les versions précédemment publiées de ce document. Bien que la SCA incite les anesthésiologistes du Canada à se conformer à son guide d'exercice pour assurer une grande qualité des soins dispensés aux patient·es, elle ne peut garantir les résultats d'une intervention spécifique. Les anesthésiologistes doivent exercer leur jugement professionnel pour déterminer la méthode d'intervention la mieux adaptée à l'état de leur patient·e. La SCA n'accepte aucune responsabilité ou imputabilité de quelque nature que ce soit découlant d'erreurs ou d'omissions ou de l'utilisation des renseignements contenus dans son Guide d'exercice de l'anesthésie.

Efficacy and Safety of Sugammadex versus Neostigmine in Reversing Neuromuscular Blockade in Morbidly Obese Adult Patients: A Systematic Review and Meta-Analysis.

CONTEXT: Sugammadex is known to reverse neuromuscular blockade (NMB) more rapidly and reliably than neostigmine. However, data remain limited in bariatric patients. In this review, we systematically evaluated the efficacy and safety of sugammadex versus neostigmine in reversing NMB in morbidly obese (MO) patients undergoing bariatric surgery. AIMS: Our primary objective was to determine the recovery time from drug administration to a train-of-four (TOF) ratio >0.9 from a moderate or deep NMB. SETTINGS AND DESIGN: This systematic review and meta-analysis (SR and MA) was conducted in accordance with the Preferred Items for SRs and MAs guidelines. SUBJECTS AND METHODS: A systematic search was conducted within multiple databases for studies that compared sugammadex and neostigmine in MO patients. STATISTICAL ANALYSIS USED: We reported data as mean difference (MD) or odds ratios (OR) and corresponding 95% confidence interval (CI) using random-effects models. A two-sided P < 0.05 was considered statistically significant. RESULTS: Seven studies with 386 participants met the inclusion criteria. Sugammadex significantly reduced the time of reversal of moderate NMB-to-TOF ratio >0.9 compared to neostigmine, with a mean time of 2.5 min (standard deviation [SD] 1.25) versus 18.2 min (SD 17.6), respectively (MD: -14.52; 95% CI: -20.08, -8.96; P < 0.00001; I 2 = 96%). The number of patients who had composite adverse events was significantly lower with sugammadex (21.2% of patients) compared to neostigmine (52.5% of patients) (OR: 0.15; 95% CI: 0.07-0.32; P < 0.00001; I 2 = 0%). CONCLUSIONS: Sugammadex reverses NMB more rapidly with fewer adverse events than neostigmine in MO patients undergoing bariatric surgery.

Incidence, Risk Factors, and Outcomes of Perioperative Atrial Fibrillation following Noncardiothoracic Surgery: A Systematic Review and Meta-Regression Analysis of Observational Studies.

BACKGROUND: Atrial fibrillation (AF) occurs in 16-30% of patients after cardiac and thoracic surgery and can lead to serious complications like hypoperfusion of vital organs, pulmonary edema, and myocardial infarction. The evidence on risk factors and complications associated with perioperative AF after noncardiothoracic surgery is limited. METHODS: The primary objective was to determine demographic and clinical risk factors for new-onset atrial fibrillation associated with noncardiothoracic surgery. A secondary aim was to identify the incidence and odds of perioperative complications associated with the new-onset atrial fibrillation. A systematic search within multiple databases was conducted for studies that explicitly reported on new-onset atrial fibrillation after noncardiothoracic surgery. We reported data on demographics, comorbidities, and perioperative complications as mean difference (MD) or odds ratios (OR) and corresponding 95% confidence interval (CI) using random effects models. A two-sided P value of less than 0.05 was considered significant. We performed meta-regression and sensitivity analysis of various subgroups to confirm the inference of our findings. RESULTS: Eleven studies reporting on 121,517 patients were included, of whom 2,944 developed perioperative AF (incidence rate: 3.7%; 95% CI: 2.3%--6.2%). Advanced age (AF group versus control group: 69.36 ± 10.5 versus 64.37 ± 9.53 years; MD: 4.06; 95% CI: 1.67--6.44; P=0.0009), male gender (52.85% versus 43.59%; OR: 1.08; 95% CI: 0.54 to 1.62; I 2: 84%; P < 0.0001), preoperative hypertension (60.42% versus 56.51%; OR: 1.15; 95% CI: 1.08 to 1.23; I 2: 0%; P < 0.00001), diabetes mellitus (22.6% versus 23.04%; OR: 0.97; 95% CI: 0.89 to 1.05; I 2: 0; P < 0.00001), and cardiac disease (30.64% versus 8.49%; OR: 2.3; 95% CI: 0.28 to 4.31; I 2: 93%; P=0.03) were found to be significant predictors for perioperative AF. The AF group was at increased odds of developing postoperative cardiac complications (34.1% versus 5%; OR: 5.44; 95% CI: 0.49 to 10.39; I 2: 82%; P=0.03), postoperative stroke (0.5% versus 0.1%; OR: 3; 95% CI: 0.65 to 5.35; I 2: 0%; P=0.01), and mortality (7.40% versus 1.92%; OR: 3.58; 95% CI: 0.14 to 7.02; I 2: 0%; P=0.04). Study quality assessment by meta-regression and sensitivity analysis of the various subgroups did not affect the final inference of the results. CONCLUSION: We identified advanced age, male gender, preoperative hypertension, diabetes mellitus, and cardiac disease as important risk factors for perioperative atrial fibrillation. The atrial fibrillation group was at increased odds for postoperative cardiac complications, stroke, and higher mortality, emphasizing the need for risk stratification and close monitoring.

Perioperative adherence to continuous positive airway pressure and its effect on postoperative nocturnal hypoxemia in obstructive sleep apnea patients: a prospective cohort study.

BACKGROUND: Although continuous positive airway pressure (CPAP) is the first line treatment for obstructive sleep apnea (OSA) patients, the perioperative adherence rate is unclear. The objective of this study was to determine the perioperative adherence rate of patients with OSA with a CPAP prescription and the effect of adherence on nocturnal oxygen saturation. METHODS: This prospective cohort study included adult surgical patients with a diagnosis of OSA with CPAP prescription undergoing elective non-cardiac surgery. Patients were divided into CPAP adherent and non-adherent groups based on duration of usage (≥ 4 h/night). Overnight oximetry was performed preoperatively and on postoperative night 1 and 2 (N1, N2). The primary outcome was adherence rate and the secondary outcome was nocturnal oxygen saturation. RESULTS: One hundred and thirty-two patients completed the study. CPAP adherence was 61% preoperatively, 58% on postoperative N1, and 59% on N2. Forty-nine percent were consistently CPAP adherent pre- and postoperatively. Using a linear fixed effects regression, oxygen desaturation index (ODI) was significantly improved by CPAP adherence (p = 0.0011). The interaction term CPAP x N1 was significant (p = 0.0015), suggesting that the effect of CPAP adherence varied on N1 vs preoperatively. There was no benefit of CPAP adherence on postoperative mean SpO2, minimum SpO2, and percentage of sleep duration with SpO2 < 90%. Use of supplemental oxygen therapy was much lower in the CPAP adherent group vs non-adherent group (9.8% vs 46.5%, p <  0.001). CONCLUSIONS: Among patients with a preoperative CPAP prescription, approximately 50% were consistently adherent. CPAP adherence was associated with improved preoperative ODI and the benefit was maintained on N1. These modest effects may be underestimated by a higher severity of OSA in the CPAP adherent group and a higher rate of oxygen supplementation in the non-adherent group. TRIAL REGISTRATION: ClinicalTrials.Gov registry ( NCT02796846 ).

Perioperative Satisfaction and Health Economic Questionnaires in Patients Undergoing an Elective Hip and Knee Arthroplasty: A Prospective Observational Cohort Study.

Background: Early hospital discharge shifts the recovery burden toward the patient and can leave patients and their caregivers anxious about the recovery process. Postoperative home care must be broadened to include appropriate and adequate support to address recovery at home. In this prospective study, patient and caregiver perspectives on the level of preparation/satisfaction and cost associated with management of recovery in the postoperative period were evaluated. Methods: We designed this prospective study to measure patient-reported outcomes and to inform the design of a postoperative home monitoring system. Patients undergoing inpatient total hip or knee replacements were recruited from a preadmission clinic at a university hospital. Patients and caregivers completed preoperative, postoperative, and health economic questionnaires. Bivariate analyses were conducted to understand factors associated with satisfaction with care. Results: Of 239 patients and caregivers recruited, preoperative questionnaire was completed by 98.8% of patients, the postoperative follow-up questionnaire was completed by 94.2% of patients, 75% of informal caregivers completed the postoperative follow-up questionnaires, and 93.7% completed the health economic questionnaire. The postoperative satisfaction scores were higher than the preoperative needs/expectation scores for both the overall and individual subscales. Patients undergoing hip arthroplasty reported higher satisfaction scores for postoperative pain management than patients undergoing knee arthroplasty (hip arthroplasty vs. knee arthroplasty: 4.07 ± 1.11 vs. 3.37 ± 1.51; P < 0.001). Patients who underwent knee arthroplasty reported better satisfaction scores with regard to having enough information on how to manage leg stiffness at home compared to patients undergoing hip arthroplasty (knee arthroplasty vs. hip arthroplasty: 3.13 ± 1.35 vs. 2.78 ± 1.30; P = 0.04). Conclusion: Overall, patients are generally satisfied with perioperative care, but they have distinct needs and expectations regarding perioperative medication and postoperative pain management. Virtual postoperative monitoring may be a useful tool during postoperative care to address many of patients' concerns.

Medications for the prevention of pruritus in women undergoing cesarean delivery with Intrathecal morphine: A systematic review and bayesian network meta-analysis of randomized controlled trials.

PURPOSE: Intrathecal morphine-induced pruritus can cause significant discomfort in parturients and is refractory to conventional antipruritic treatment. This systematic review and network meta-analysis evaluates the effectiveness of the medications used for prevention of intrathecal (IT) morphine-induced pruritus after cesarean delivery under spinal anesthesia. METHODS: A literature search was conducted from 1946 up to October 2019. We included all randomized controlled trials (RCTs) that compared medications used for prevention of pruritus with a control group in women undergoing cesarean delivery under spinal anesthesia with IT morphine. The primary outcome examined was the incidence of pruritus up to 24 h after cesarean delivery. Dichotomous data were extracted and summarized using odds ratios (OR) and 95% credible intervals (CrI) with Bayesian random effects network meta-analysis model. The GRADE approach was used to evaluate quality of the studies and effect evidence. RESULTS: Of the 26 studies included in the systematic review, 21 studies with a total of 2594 patients were included in the network meta-analysis [prophylaxis, n = 1603 (62%) vs. control, n = 991 (38%)]. These studies investigated seven classes of drugs including serotonin-receptor antagonists, dopamine-receptor antagonists, opioid agonist-antagonists, opioid-receptor antagonists, histamine-receptor antagonists, propofol and celecoxib. The network meta-analysis showed that serotonin-receptor antagonists' prophylaxis [control vs. prophylaxis: 60% vs. 47%; OR (95% CrI): 2.69 (1.43-5.36)] and opioid agonist-antagonists prophylaxis [control vs. prophylaxis: 72% vs. 47%; OR (95% CrI): 4.57 (1.67-12.91)] decreased the incidence of pruritus compared to the control group. Although all included studies were at low risk of bias, the quality of the overall network meta-analysis pooled estimates was low. CONCLUSION: This bayesian network meta-analysis of RCTs demonstrates serotonin-receptor antagonists and opioid agonist-antagonists may prevent pruritus in women undergoing cesarean delivery with intrathecal morphine compared to control group. However, further RCTs of adequate power and clearly defined end points are warranted.

Effect of intrathecal lipophilic opioids on the incidence of shivering in women undergoing cesarean delivery after spinal anesthesia: a systematic review and bayesian network meta- analysis of randomized controlled trials.

BACKGROUND: Shivering is a common side effect in women having cesarean delivery (CD) under spinal anesthesia, which can be bothersome to the patient, and it can also interfere with perioperative monitoring. In several studies, the intrathecal (IT) addition of a lipophilic opioid to local anesthetics has been shown to decrease the incidence of shivering. OBJECTIVE: We performed this network meta-analysis to evaluate the effects of intrathecal lipophilic opioids in preventing the incidence of shivering in patients undergoing CD. METHODS: This review was planned according to the PRISMA for Network Meta-Analysis (PRISMA-NMA) guidelines. An English literature search of multiple electronic databases was conducted. We included randomized controlled trials (RCTs) that reported on the incidence of shivering, with study groups receiving either IT fentanyl, sufentanil, or meperidine in women undergoing CD under spinal anesthesia. Quality of the studies was assessed using the modified Oxford scoring system. Using random-effects modeling, dichotomous data were extracted and summarized using odds ratio (OR) with a 95% credible interval (CrI). Statistical analysis was conducted using R studio version 1.0.153 - Inc. RESULTS: Twenty-one studies consisting of 1433 patients (Control group: 590 patients in twenty-one studies; Fentanyl group:199 patients in seven studies; Sufentanil group: 156 patients in five studies; Meperidine group: 488 patients in ten studies) met the inclusion criteria for this systematic review investigating the effect of intrathecal lipophilic opioids in preventing the incidence of shivering in women undergoing cesarean delivery under spinal anesthesia. Methodological validity scores ranged from 3 to 7. The Bayesian mixed network estimate showed the incidence of shivering was significantly lower with IT fentanyl (pooled odds ratio (OR): 0.13; 95% credible interval (CrI): 0.04 to 0.35; P = 0.0004) and IT meperidine (OR: 0.12; 95% CrI: 0.05 to 0.29; P < 0.00001), but not with IT sufentanil (OR: 0.37; 95% CrI: 0.11 to 1.22; P = 0.23). The IT fentanyl group had a significantly lower incidence of intraoperative discomfort [Risk Ratio (RR): 0.19; 95% CI: 0.10-0.35; P < 0.00001], the IT sufentanil group had a significantly higher incidence of pruritus (RR: 6.18; 95% CI: 1.18-32.46; P = 0.03) The IT meperidine group had a significantly lower incidence of intraoperative discomfort (2.7% vs. 13.6%; RR: 0.22; 95% CI: 0.09-0.55; P = 0.001), but there was a significant increase in nausea and vomiting (IT meperidine group vs. Control group: 42.7% vs. 19.4%; RR: 2.56; 95% CI: 1.14-5.75; P = 0.02). Meta-regression analysis based on the opioid dose and quality of the study did not impact the final inference of our result. CONCLUSION: IT fentanyl significantly decreased the incidence of shivering in women undergoing CD under spinal anesthesia without increasing maternal adverse events, confirming that routine use in this patient population is a good choice. IT sufentanil did not decrease the incidence of shivering. IT meperidine decreased the incidence and severity of shivering, but its use was also associated with significant nausea and vomiting.

Preoperative Evaluation: Estimation of Pulmonary Risk Including Obstructive Sleep Apnea Impact.

One in 4 deaths occurring within a week of surgery are related to pulmonary complications, making it the second most common serious morbidity after cardiovascular events. The most significant predictors of the postoperative pulmonary complications (PPCs) are American Society of Anesthesiologists physical status, advanced age, dependent functional status, surgical site, and duration of surgery. The overall risk of PPCs can be predicted using scores that incorporate readily available clinical data.

Best perioperative practice in management of ambulatory patients with obstructive sleep apnea.

PURPOSE OF REVIEW: The perioperative outcome in obstructive sleep apnea (OSA) patients undergoing ambulatory surgery can be potentially impacted by the type of anesthetic technique, fluid management and choice of anesthetic agents. This review highlights the best perioperative practices in the management of OSA patients undergoing ambulatory surgical procedures. RECENT FINDINGS: A recent meta-analysis found that STOP-Bang might be used as a perioperative risk stratification tool. Patients with high-risk OSA (STOP-Bang ≥3) were found to be associated with an increased risk of postoperative complications and prolonged length of hospital stay compared with low-risk OSA (STOP-Bang 0-2) patients undergoing noncardiac surgical procedures. A bidirectional relationship exists between OSA and difficult airway. Both suspected or diagnosed OSA may be associated with either difficult intubation or difficult mask ventilation or both. A recent meta-analysis identified OSA as an important risk factor for opioid-induced respiratory depression. A dose-response relationship was shown between the morphine equivalent daily dose and death or near-death events in OSA patients undergoing surgery. Postoperative continuous monitoring is recommended for high-risk OSA patients receiving opioids. Minimising the dose of muscle relaxant, neuromuscular monitoring and ensuring complete reversal of neuromuscular blockade before extubation is essential in OSA patients to avoid postoperative complications. Whenever feasible, regional anesthesia with multimodal analgesia may be considered as a better alternative to general anesthesia in OSA patients. SUMMARY: Patients with OSA and associated comorbidities present a challenge to anesthesiologists as they are at a high risk of perioperative complications. It is important to identify patients with OSA, with the goal to raise awareness among providers, mitigate risk and improve outcomes.

Association of STOP-Bang Questionnaire as a Screening Tool for Sleep Apnea and Postoperative Complications: A Systematic Review and Bayesian Meta-analysis of Prospective and Retrospective Cohort Studies.

BACKGROUND: The risk of postoperative complications increases with undiagnosed obstructive sleep apnea (OSA). The high-risk OSA (HR-OSA) patients can be easily identified using the STOP-Bang screening tool. The aim of this systematic review and meta-analysis is to determine the association of postoperative complications in patients screened as HR-OSA versus low-risk OSA (LR-OSA). METHODS: The following data bases were searched from January 1, 2008, to October 31, 2016, to identify the eligible articles: Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, Cochrane Databases of Systematic Reviews, Medline-in-Process & other nonindexed citations, Google Scholar, Embase, Web of Sciences and Scopus. The search included studies with adult surgical patients screened for OSA with STOP-Bang questionnaire that reported at least 1 cardiopulmonary or any other complication requiring intensive care unit admission as diagnosis of outcome. We used a Bayesian random-effects analysis to evaluate the existing evidence of STOP-Bang in relation to OSA and to assess the association of postoperative complications with the identified HR-OSA patients by study design and methodologies. RESULTS: This systematic review and meta-analysis was conducted using 10 cohort studies: 23,609 patients (HR-OSA, 7877; LR-OSA, 15,732). The pooled odds of perioperative complications were higher in the HR-OSA versus LR-OSA patients (odds ratio 3.93, 95% credible interval, 1.85-7.77, P= .003; 6.86% vs 4.62%). The length of hospital stay was longer in HR-OSA by 2 days when compared with LR-OSA (5.0 ± 4.2 vs 3.4 ± 2.8 days; mean difference 2.01; 95% credible interval, 0.77-3.24; P= .005). Meta-regression to adjust for baseline confounding factors and subgroup analysis did not materially change the results. CONCLUSIONS: This systematic review and meta-analysis suggests that HR-OSA is related with higher risk of postoperative adverse events and longer length of hospital stay when compared with LR-OSA patients. Our findings support the implementation of the STOP-Bang screening tool for perioperative risk stratification.

Optimal propofol induction dose in morbidly obese patients: A randomized controlled trial comparing the bispectral index and lean body weight scalar.

PURPOSE: Propofol dosing based on total body weight (TBW) can lead to overdosing in morbidly obese (MO) patients. Our aim was to determine whether an induction dose of propofol based on a bispectral index (BIS) target is better for achieving loss of consciousness in MO patients than dosing based on lean body weight (LBW). METHODS: Sixty MO patients with a body mass index (BMI) of ≥ 40 kg·m-2 were randomized to either BIS- or LBW-based propofol dosing groups. Anesthesia was induced with a propofol infusion of 100 mg·kg-1·hr-1 to an initial target endpoint of a BIS of 50 (BIS group) or until a precalculated dose of 2.6 mg·kg-1 LBW based on the Janmahasatian equation was administered (LBW group). Induction was assessed using the observer's assessment alertness/sedation scale (OAA/S). If an OAA/S score of 0 was not achieved, infusions continued until it reached 0. The groups were compared for the primary outcome which was the difference in the propofol doses at the initial target endpoint. RESULTS: The median [interquartile range] OAA/S score at the initial target endpoint was lower in the BIS group than in the LBW group (0 [0-0] vs 1 [0-3], respectively; median difference 1, 95% confidence interval [CI] 0 to 3; P = 0.001). The number of patients requiring additional propofol doses was also higher for the LBW group [1 vs 18 patients, respectively; relative risk of requiring additional propofol 18; 95% CI 3 to 126; P = 0.001]. The mean (SD) propofol dose at the target endpoint was significantly lower in the LBW group than in the BIS group [164 (36) mg vs 225 (44) mg, respectively; mean difference 61 mg; 95% CI 41 to 83 mg; P = 0.002]. There was no difference between the two groups, however, regarding the total induction dose of propofol needed for the OAA/S to reach 0 (P = 0.07). CONCLUSION: The induction dose of propofol based on the BIS index was different from the induction dose based on LBW in MO patients. Patients in the LBW group required additional propofol to achieve an OAA/S of 0.

The Benefits of Perioperative Screening for Sleep Apnea in Surgical Patients.

Obstructive sleep apnea (OSA) is a chronic disease affecting millions of people worldwide. Untreated OSA can lead to about a 2-fold increase in medical expenses, mainly because of cardiovascular morbidity. OSA is highly prevalent in the surgical population, with an increased risk of perioperative complications. This article describes the perioperative and long-term social and economic benefits of preoperative screening for OSA. Screening patients to identify high-risk OSA is important to decrease the adverse outcomes and associated health care costs in the perioperative period. Screening for OSA is particularly relevant because most patients are undiagnosed at the time of surgery.

Understanding Phenotypes of Obstructive Sleep Apnea: Applications in Anesthesia, Surgery, and Perioperative Medicine.

Obstructive sleep apnea (OSA) is a prevalent sleep-disordered breathing with potential long-term major neurocognitive and cardiovascular sequelae. The pathophysiology of OSA varies between individuals and is composed of different underlying mechanisms. Several components including the upper airway anatomy, effectiveness of the upper airway dilator muscles such as the genioglossus, arousal threshold of the individual, and inherent stability of the respiratory control system determine the pathogenesis of OSA. Their recognition may have implications for the perioperative health care team. For example, OSA patients with a high arousal threshold are likely to be sensitive to sedatives and narcotics with a higher risk of respiratory arrest in the perioperative period. Supplemental oxygen therapy can help to stabilize breathing in OSA patients with inherent respiratory instability. Avoidance of supine position can minimize airway obstruction in patients with a predisposition to upper airway collapse in this posture. In this review, the clinically relevant endotypes and phenotypes of OSA are described. Continuous positive airway pressure (CPAP) therapy is the treatment of choice for most patients with OSA but tolerance and adherence can be a problem. Patient-centered individualized approaches to OSA management will be the focus of future research into developing potential treatment options that will help decrease the disease burden and improve treatment effectiveness.

Cardiorespiratory effects of balancing PEEP with intra-abdominal pressures during laparoscopic cholecystectomy.

BACKGROUND: Applying appropriate positive end-expiratory pressure (PEEP) to corresponding intra-abdominal pressure (IAP) can improve gas exchange during capnoperitoneum without any hemodynamic effects. MATERIALS AND METHODS: A total of 75 patients were randomly allocated to group 0PEEP (n=25), group 5PEEP (n=25), and group 10PEEP (n=25) according to the level of PEEP, in whom capnoperitoneum was created with IAP of 14, 8, and 14 mm Hg, respectively. Hemodynamic and respiratory parameters were recorded up to 30 minutes after capnoperitoneum. RESULTS: In 0PEEP group, mean end-tidal carbon dioxide demonstrated significant rise 2 minutes after capnoperitoneum and plateaued at about 15 minutes but remained at high level for up to 30 minutes when compared with the 5PEEP and 10PEEP groups (P<0.05). Correspondingly, the mean PaCO2 (48.0±4.1 mm Hg) for the 0PEEP group was higher at 30 minutes when compared with 5PEEP (37.8±2.7 mm Hg) and 10PEEP (37.2±3.9 mm Hg) groups. The oxygenation was better preserved in 5PEEP and 10PEEP groups with significantly higher PaO2/Fio2 ratio. Heart rate, mean arterial pressure, and cardiac output remained stable throughout the study in all the 3 groups. CONCLUSIONS: Application of appropriate PEEP corresponding to the IAP helped maintain CO2 elimination and improved oxygenation without any hemodynamic disturbance in patients undergoing laparoscopic cholecystectomy.