Morphometric and ultrasonographic determinants of difficult laryngoscopy in obese patients: A prospective observational study.

BACKGROUND: Obese people have a higher risk of difficult laryngoscopy due to their thick neck, large tongue, and redundant pharyngeal soft tissue. However, there is still no established predictive factor for difficult laryngoscopy in obese population. METHODS: We conducted a prospective assessor-blind observational study to enroll adult patients with a body mass index of 30 kg·m-2 or higher undergoing laparoscopic sleeve gastrectomy at a medical center between May 2020 and August 2021. Conventional morphometric characteristics along with ultrasonographic airway parameters were evaluated before surgery. The primary outcome was difficult laryngoscopy, defined as a Cormack and Lehane's grade III or IV during direct laryngoscopy. Logistic regression analyses were performed to evaluate the association between included factors and difficult laryngoscopy. Discrimination performance of predictive factors was assessed using area under the receiver operating characteristic curve (AUC). RESULTS: A total of 80 patients were evaluated, and 17 (21.3%) developed an event of difficult laryngoscopy. Univariate analyses identified five factors associated with difficult laryngoscopy, including age, sex, hypertension, neck circumference, and cross-sectional area of tongue base. After adjusting for these variables, neck circumference was the only independent influential factor, adjusted odds ratio: 1.227 (95% confidence interval, 1.009-1.491). Based on Youden's index, the optimal cutoff of neck circumference was 49.1 cm with AUC: 0.739 (sensitivity: 0.588, specificity: 0.889; absolute risk difference: 0.477, and number needed to treat: 3). CONCLUSION: Greater neck circumference was an independent risk factor for difficult laryngoscopy in obese patients. This finding provides a way of reducing unanticipated difficult airway in this high-risk population.

A Comparison of Oxygenation Efficacy between High-Flow Nasal Cannulas and Standard Facemasks during Elective Tracheal Intubation for Patients with Obesity: A Randomized Controlled Trial.

Obese patients are predisposed to rapid oxygen desaturation during tracheal intubation. We aimed to compare the risk of desaturation between high-flow nasal oxygenation (HFNO) and classical facemask oxygenation (FMO) during rapid sequence intubation for elective surgery in obese patients. Adults with a body mass index ≥30 kg·m−2 undergoing laparoscopic sleeve gastrectomy at a medical center were randomized into the HFNO group (n = 40) and FMO group (n = 40). In the HFNO group, patients used a high-flow nasal cannula to receive 30 to 50 L·min−1 flow of heated and humidified 100% oxygen. In the FMO group, patients received a fitting facemask with 15 L·min−1 flow of 100% oxygen. After 5-min preoxygenation, rapid sequence intubation was performed. The primary outcome was arterial desaturation during intubation, defined as a peripheral capillary oxygen saturation (SpO2) <92%. The risk of peri-intubation desaturation was significantly lower in the HFNO group compared to the FMO group; absolute risk reduction: 0.20 (95% confidence interval: 0.05−0.35, p = 0.0122); number needed to treat: 5. The lowest SpO2 during intubation was significantly increased by HFNO (median 99%, interquartile range: 97−100) compared to FMO (96, 92−100, p = 0.0150). HFNO achieved a higher partial pressure of arterial oxygen (PaO2) compared to FMO, with medians of 476 mmHg (interquartile range: 390−541) and 397 (351−456, p = 0.0010), respectively. There was no difference in patients' comfort level between groups. Compared with standard FMO, HFNO with apneic oxygenation reduced arterial desaturation during tracheal intubation and enhanced PaO2 among patients with obesity.

Adverse Outcomes after Non-Cardiac Surgeries in Patients with Heart Failure: A Propensity-Score Matched Study.

The impact of heart failure (HF) on postoperative outcomes is not completely understood. Our purpose is to investigate complications and mortality after noncardiac surgeries in people who had HF. In the analyses of research data of health insurance in, we identified 32,808 surgical patients with preoperative HF and 32,808 patients without HF undergoing noncardiac surgeries. We used a matching procedure with propensity score and considered basic characteristics, coexisting diseases, and information of index surgery between patients with and without HF. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for complications and mortality after noncardiac surgeries in patients with HF were analyzed in multivariate logistic regressions. HF increased the risks of postoperative acute myocardial infarction (OR 2.51, 95% CI 1.99-3.18), pulmonary embolism (OR 2.46, 95% CI 1.73-3.50), acute renal failure (OR 1.97, 95% CI 1.76-2.21), intensive care (OR 1.93, 95% CI 1.85-2.01), and 30-day in-hospital mortality (OR 1.80, 95% CI 1.59-2.04). Preoperative emergency care, inpatient care, and injections of diuretics and cardiac stimulants due to heart failure were also associated with mortality after surgery. Patients with HF had increased complications and mortality after noncardiac surgeries compared with those without HF. The surgical care team may consider revising the protocols for perioperative care in patients with HF.

Recovery Profiles of Sevoflurane and Desflurane with or without M-Entropy Guidance in Obese Patients: A Randomized Controlled Trial.

Obesity increases the risk of prolonged emergence from general anesthesia due to the delayed release of anesthetic agents from body fat. This trial aimed to evaluate the effects of sevoflurane and desflurane along with anesthetic depth monitoring on emergence time from anesthesia in obese patients. Adults with a body mass index ≥ 30 kg·m-2 undergoing laparoscopic sleeve gastrectomy at a medical center were randomized into four groups: sevoflurane or desflurane anesthesia with or without M-Entropy guidance on anesthetic depth in a ratio of 1:1:1:1. In the M-Entropy guidance groups, the dosage of sevoflurane and desflurane was adjusted to achieve response and state entropy values between 40 and 60 during surgery. In the non-M-Entropy guidance groups, the dosage of anesthetics was titrated according to clinical signs. Primary outcome was time to spontaneous eye opening. A total of 80 participants were randomized. Compared to sevoflurane, desflurane anesthesia significantly reduced the time to spontaneous eye opening [mean difference (MD): -129 s; 95% confidence interval (CI): -211, -46], obeying commands (-160; -243, -77), tracheal extubation (-172; -266, -78), and leaving operating room (-148; -243, -54). M-Entropy guidance further reduced time to eye opening (MD: -142 s; 99.2% CI: -276, -8), tracheal extubation (-199; -379, -19), and leaving operating room (-190; -358, -23) in the desflurane but not the sevoflurane group. M-Entropy guidance significantly reduced the risk of agitation during emergence, i.e., risk difference: -0.275 (95% CI: -0.464, -0.086); and number needed to treat: 4. Compared to sevoflurane, using desflurane to maintain general anesthesia accelerated the return of consciousness in obese patients. M-Entropy guidance further hastened awakening in patients using desflurane and prevented emergence agitation.

Outcomes After Nonobstetric Surgery in Pregnant Patients: A Nationwide Study.

OBJECTIVE: To evaluate outcomes after nonobstetric surgical procedures in pregnant patients. METHODS: We conducted a retrospective cohort study of 5591 pregnant women who underwent nonobstetric surgical procedures using Taiwan's National Health Insurance Research Database 2008-2012 claims data. Using a propensity score matching procedure, 22,364 nonpregnant women were selected for comparison. Logistic regression was used to calculate the odds ratios (ORs) and 95% CIs of postoperative complications and in-hospital mortality associated with pregnancy. RESULTS: Pregnant women had higher risks of postoperative septicemia (OR=1.75; 95% CI, 1.47-2.07), pneumonia (OR=1.47; 95% CI, 1.01-2.13), urinary tract infection (OR=1.29; 95% CI, 1.08-1.54), and in-hospital mortality (OR=3.94; 95% CI, 2.62-5.92) compared with nonpregnant women. Pregnant women also had longer hospital stays and higher medical expenditures after nonobstetric surgical procedures than controls. Higher rates of postoperative adverse events in pregnant women receiving nonobstetric surgery were noted in all age groups. CONCLUSION: Surgical patients with pregnancy showed more adverse events, with a risk of in-hospital mortality approximately 4-fold higher after nonobstetric surgery compared with nonpregnant patients. These findings suggest the urgent need to revise the protocols for postoperative care for this population.

Risk and mortality of gastrointestinal hemorrhage in patients with thrombocytopenia: Two nationwide retrospective cohort studies.

INTRODUCTION: The association between thrombocytopenia (TP) and gastrointestinal hemorrhage was not completely understood. The purpose of this study is to evaluate the risk of gastrointestinal hemorrhage and post-hemorrhage mortality in patients with TP. METHODS: Using the Taiwan National Health Insurance Research Database, we identified 1033 adults aged ≥18 years diagnosed with TP in 2000-2003. Non-TP cohort consisted of 10,330 adults randomly selected and matched by age and sex from the same dataset. Incident events of gastrointestinal hemorrhage occurring after TP from January 1, 2000, through December 31, 2008, were ascertained from medical claims. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of gastrointestinal hemorrhage associated with TP were calculated. Another nested cohort study consisted of 27,369 patients with hospitalization due to gastrointestinal hemorrhage between January 1, 2004, and December 31, 2010. We calculated the adjusted odds ratios (ORs) and 95% CIs of 30-day mortality after gastrointestinal hemorrhage in patients with and without TP during admission. RESULTS: The incidences of gastrointestinal hemorrhage for people with and without TP were 14.5 and 5.07 per 1000 person-years, respectively (P<0.0001). Compared to people without TP, patients with TP had increased risk of gastrointestinal hemorrhage (HR, 2.61; 95% CI, 2.05-3.32). In the nested cohort study, TP was associated with post-hemorrhage mortality (OR, 1.98; 95% CI, 1.09-3.59). CONCLUSION: Patients with TP showed higher risks of gastrointestinal hemorrhage and post-hemorrhage mortality. Our findings suggest the urgency of preventing and managing gastrointestinal hemorrhage by a multidisciplinary medical team for this specific population.

Postoperative recovery after anesthesia in morbidly obese patients: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: Obese patients present a challenge to safe general anesthesia because of impaired cardiopulmonary physiology and increased risks of aspiration and acute upper airway obstruction. Since studies are lacking regarding the postoperative effects on recovery from general anesthesia in morbidly obese patients, we conducted a systematic review and meta-analysis of recovery outcomes in morbidly obese patients who had undergone general anesthesia. SOURCE: We systematically searched the PubMed, EMBASE™, Cochrane, and Scopus™ databases for randomized controlled trials that evaluated the outcome of anesthesia with desflurane, sevoflurane, isoflurane, or propofol in morbidly obese patients. Using a random effects model, we conducted meta-analyses to assess recovery times (eye opening, hand squeezing, tracheal extubation, and stating name or birth date), time to discharge from the postanesthesia care unit (PACU), and the incidence and severity of postoperative nausea and vomiting (PONV). PRINCIPAL FINDINGS: We reviewed results for 11 trials and found that patients given desflurane took less time: to respond to commands to open their eyes (weighted mean difference [WMD] -3.10 min; 95% confidence interval (CI): -5.13 to -1.08), to squeeze the investigator's hand (WMD -7.83 min; 95% CI: -8.81 to -6.84), to be prepared for tracheal extubation (WMD -3.88 min; 95% CI: -7.42 to -0.34), and to state their name (WMD -7.15 min; 95% CI: -11.00 to -3.30). We did not find significant differences in PACU discharge times, PONV, or the PACU analgesic requirement. CONCLUSION: Postoperative recovery was significantly faster after desflurane than after sevoflurane, isoflurane, or propofol anesthesia in obese patients. No clinically relevant differences were observed regarding PACU discharge time, incidence of PONV, or postoperative pain scores. The systematic review was registered with PROSPERO (CRD42014009480).

Modeling the Trajectory of Analgesic Demand Over Time After Total Knee Arthroplasty Using the Latent Curve Analysis.

OBJECTIVES: Patient-controlled epidural analgesia (PCEA) is commonly used for pain relief after total knee arthroplasty (TKA). This study aimed to model the trajectory of analgesic demand over time after TKA and explore its influential factors using latent curve analysis. METHODS: Data were retrospectively collected from 916 patients receiving unilateral or bilateral TKA and postoperative PCEA. PCEA demands during 12-hour intervals for 48 hours were directly retrieved from infusion pumps. Potentially influential factors of PCEA demand, including age, height, weight, body mass index, sex, and infusion pump settings, were also collected. A latent curve analysis with 2 latent variables, the intercept (baseline) and slope (trend), was applied to model the changes in PCEA demand over time. The effects of influential factors on these 2 latent variables were estimated to examine how these factors interacted with time to alter the trajectory of PCEA demand over time. RESULTS: On average, the difference in analgesic demand between the first and second 12-hour intervals was only 15% of that between the first and third 12-hour intervals. No significant difference in PCEA demand was noted between the third and fourth 12-hour intervals. Aging tended to decrease the baseline PCEA demand but body mass index and infusion rate were positively correlated with the baseline. Only sex significantly affected the trend parameter and male individuals tended to have a smoother decreasing trend of analgesic demands over time. Patients receiving bilateral procedures did not consume more analgesics than their unilateral counterparts. Goodness of fit analysis indicated acceptable model fit to the observed data. CONCLUSIONS: Latent curve analysis provided valuable information about how analgesic demand after TKA changed over time and how patient characteristics affected its trajectory.

Innominate artery dissection with presentation of sudden right frontal desaturation detected by cerebral oximetry in complicated thoracic aortic aneurysm repair surgery: a case report.

Cerebral oximetry is a noninvasive bedside monitor for cerebral oxygen saturation (rSO(2)). A patient with a thoracic aneurysm underwent combined surgical and endovascular repair. A sudden decrease in right rSO(2) led to the finding of acute innominate artery dissection. Immediate repair was instituted. Sudden asymmetry of rSO(2) may be a warning sign of underlying pathology.

Bilateral tension pneumothorax and tension pneumoperitoneum secondary to tracheal tear in a patient with relapsing polychondritis.

Relapsing polychondritis (RP) is a rare disease that is characterized by recurrent inflammation and destruction of cartilage and connective tissues. RP can have significant airway pathology that may require procedures to maintain airway patency and thus may have serious implications for anesthesiologists. Anesthesiologists must be prepared to deal with the possible complications that may occur during airway manipulation in patients with RP. Here, we present a case of life-threatening bilateral tension pneumothorax and tension pneumoperitoneum that developed after a tracheal tear during Montgomery T-tube insertion in a patient with tracheal stenosis due to RP. Correct diagnosis was delayed due to a misdiagnosis of airway obstruction. As a result, we emphasize that bilateral tension pneumothorax should be considered during refractory cardiac arrest in patients with increased airway pressure. A high index of suspicion and adequate management are mandatory for patients to survive these life-threatening complications.

Factors associated with vomiting in orthopedic patients receiving patient-controlled epidural analgesia.

BACKGROUND: Although patient-controlled epidural analgesia (PCEA) can effectively relieve postoperative pain in orthopedic patients, some adverse effects are still troublesome. We conducted this study to survey the possible risk factors related to vomiting induced by PCEA. METHODS: This retrospective study was conducted to review orthopedic patients receiving postoperative PCEA. The agent for PCEA was bupivacaine prepared as a 0.1% solution with added fentanyl (1 microg/mL). Patients' characteristics including demographic data and types of surgical procedures were collected. All patients were dichotomized into vomiting and non-vomiting groups and subgroup comparisons were also performed. Stepwise logistic regression analyses were conducted to determine significant factors associated with vomiting in these patients. RESULTS: There were 320 patients (111 men, 209 women) included in the analysis. No significant differences in demographic data were noted between the groups except in sex distribution. Factors related to surgery, anesthesia and PCEA were similar between groups (p > 0.05 in all). The incidence of vomiting for orthopedic patients receiving PCEA was about 9.7% (12.4% for female, 4.5% for male). After stepwise model selection, we found female sex was the only risk factor of vomiting. The odds ratio of vomiting for female gender was 3 (95% confidence interval, 1.1-8.1). General anesthesia was not associated with vomiting in these patients. CONCLUSION: Our study demonstrated the risk factor associated with vomiting for orthopedic patients receiving PCEA was female sex. Other demographic variables and factors related to surgery or anesthesia did not have an influence on vomiting.