The impact of perioperative ketamine or esketamine on the subjective quality of recovery after surgery: a meta-analysis of randomised controlled trials.

BACKGROUND: This meta-analysis aimed to evaluate the impact of ketamine/esketamine on postoperative subjective quality of recovery (QoR). METHODS: MEDLINE, Embase, Cochrane library, and Google Scholar were searched for randomised controlled trials (RCTs) that examined the impacts of perioperative ketamine/esketamine use and postoperative QoR. The primary outcome was subjective QoR (QoR-9, QoR-15, QoR-40) on postoperative day (POD) 1-3, whereas the secondary outcomes included pain severity, anxiety scores, depression scores, risk of adverse events (i.e. nausea, vomiting, dizziness, drowsiness), and length of stay. RESULTS: The analysis included 18 RCTs (1554 participants; ketamine: seven trials, esketamine: 11 trials), of which 15 were conducted in China. Ketamine/esketamine improved the QoR scores on PODs 1 and 2 compared with the control (standardised mean difference [SMD]: 0.63, P<0.0001 for POD 1; SMD: 0.56, P=0.04 for POD 2), without beneficial effect on POD 3. Subgroup analyses revealed significant differences in QoR scores on POD 1 by regimen (SMD: esketamine 1.14, ketamine 0.01) and country (SMD: China 0.82, other countries -0.21). The emotional domain of QoR was improved from PODs 1 to 3, whereas the other domains were only improved on POD 1. Lower postoperative anxiety (SMD: -0.48, P=0.003) and depression (SMD: -0.72, P=0.001) scores were also observed with ketamine/esketamine use. Furthermore, pain severity was reduced on PODs 1 and 2, with no difference in the risk of adverse events or length of stay. CONCLUSIONS: This meta-analysis demonstrated that ketamine/esketamine use in the perioperative period is associated with improved early subjective QoR, pain severity, and psychological symptoms without an increase in the likelihood of adverse events. SYSTEMATIC REVIEW PROTOCOL: PROSPERO (CRD42023477580).

Systemic immune-inflammation index for predicting postoperative atrial fibrillation following cardiac surgery: a meta-analysis.

Background: Postoperative atrial fibrillation (POAF) is a frequent complication that may increase morbidity and mortality risk following cardiac surgery. The systemic immune-inflammation index (SII) is an emerging biomarker that provides an integrated measure of inflammation by incorporating neutrophil, lymphocyte, and platelet counts. Recent studies have reported associations between elevated SII and increased POAF risk; however, significant heterogeneity exists regarding its predictive efficacy. This meta-analysis aimed to assess SII's diagnostic efficacy for predicting POAF risk. Methods: To synthesize existing evidence on the ability of perioperative SII for predicting POAF in patients undergoing cardiac surgery, a systematic review and meta-analysis was conducted. In August 2023, a comprehensive literature search was performed to identify relevant studies reporting SII cutoff values with corresponding sensitivity and specificity. The primary aim was to evaluate SII's diagnostic utility for predicting POAF, whereas secondary outcomes included the pooled incidence of POAF and the relationship between the SII and POAF. Results: Eight studies published between 2021 and 2023 with 3,245 patients were included. Six studies involved coronary artery bypass grafting (CABG) surgery; one encompassed various cardiac procedures, and another focused solely on mitral valve surgery. The pooled incidence of POAF was 23.6% [95% confidence interval (CI), 18.7%-29.2%]. Elevated SII significantly increased the odds of POAF by 3.24-fold (odds ratio, 3.24; 95% CI, 1.6-6.55; p = 0.001). SII's pooled sensitivity and specificity for predicting POAF were 0.80 (95% CI, 0.68-0.89) and 0.53 (95% CI, 0.23-0.8), respectively. The SII had moderate predictive accuracy based on a hierarchical summary receiver operating characteristic (HSROC) area under the curve of 0.78 (95% CI, 0.74-0.81). Subgroup analyses, whether focusing on CABG alone or CABG with cardiopulmonary bypass (CPB), both indicated an area under the HSROC curve of 0.78 (95% CI, 0.74-0.81). Conclusion: Elevated SII is significantly correlated with an increased POAF risk following cardiac surgery, highlighting its utility as a predictive biomarker. Considering its moderate diagnostic accuracy, further research is essential for clarifying SII's clinical effectiveness, either as an independent predictor or combined with other risk factors, for stratifying patients at high POAF risk. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier [CRD42023456128].

Prediction of early postoperative pain using sleep quality and heart rate variability.

PURPOSE: Accurate predictions of postoperative pain intensity are necessary for customizing analgesia plans. Insomnia is a risk factor for severe postoperative pain. Moreover, heart rate variability (HRV) can provide information on the sympathetic-parasympathetic balance in response to noxious stimuli. We developed a prediction model that uses the insomnia severity index (ISI), HRV, and other demographic factors to predict the odds of higher postoperative pain. METHODS: We recruited gynecological surgery patients classified as American Society of Anesthesiologists class 1-3. An ISI questionnaire was completed 1 day before surgery. HRV was calculated offline using intraoperative electrocardiogram data. Pain severity at the postanesthesia care unit (PACU) was assessed with the 0-10 numerical rating scale (NRS). The primary outcome was the model's predictive ability for moderate-to-severe postoperative pain. The secondary outcome was the relationship between individual risk factors and opioid consumption in the PACU. RESULTS: Our study enrolled 169 women. Higher ISI scores (p = 0.001), higher parasympathetic activity (rMSSD, pNN50, HF; p < 0.001, p < 0.001, p < 0.001), loss of fractal dynamics (SD2, alpha 1; p = 0.012, p = 0.039) in HRV analysis before the end of surgery were associated with higher NRS scores, while laparoscopic surgery (p = 0.031) was associated with lower NRS scores. We constructed a multiple logistic model (area under the curve = 0.852) to predict higher NRS scores at PACU arrival. The five selected predictors were age (OR: 0.94; p = 0.020), ISI score (OR: 1.14; p = 0.002), surgery type (laparoscopic or open; OR: 0.12; p < 0.001), total power (OR: 2.02; p < 0.001), and alpha 1 (OR: 0.03; p < 0.001). CONCLUSION: We employed a multiple logistic regression model to determine the likelihood of moderate-to-severe postoperative pain upon arrival at the PACU. Physicians could personalize analgesic regimens based on a deeper comprehension of the factors that contribute to postoperative pain.

Association between the neutrophil-to-lymphocyte ratio and cognitive impairment: a meta-analysis of observational studies.

Background: Systemic inflammation is one of the underlying mechanisms of cognitive impairment. The neutrophil-to-lymphocyte ratio (NLR) has emerged as a systemic inflammation indicator. This meta-analysis aimed to evaluate the association between high NLR and cognitive impairment (CI) risk. Method: A comprehensive systematic search was conducted to identify eligible studies published until May 30, 2023. The reference group comprised patients with the lowest NLR level, whereas the exposure group comprised those with the highest NLR level. The main outcome was to examine the relationship between NLR and CI risk. The secondary outcome included the association between patient characteristics or comorbidities and CI risk. Results: This meta-analysis included 11 studies published between 2018 and 2023, involving 10,357 patients. Patients with CI had a higher NLR than those without (mean difference=0.35, 95% confidence interval [CI]: 0.26-0.44, p < 00001, I2 = 86%). Consistently, pooled results revealed an association between high NLR and CI risk (odds ratio [OR]=2.53, 95% CI:1.67-3.82, p<0.0001, I2 = 84%). Furthermore, aging (mean difference =4.31 years, 95% CI:2.83-5.8, p < 0.00001, I2 = 92%), diabetes (OR=1.59, 95% CI:1.35-1.88, p < 0.00001, I2 = 66%), and hypertension (OR=1.36, 95% CI:1.19-1.57, p < 0.00001, I2 = 0%) were significant risk factors for CI. However, no significant associations were observed between CI and male gender (OR = 0.84, 95% CI:0.64-1.11, p = 0.22, I2 = 81%), body mass index (mean = -0.32 kg/m2, 95% CI: -0.82, 0.18, p = 0.2, I2 = 82%), alcohol consumption (OR = 1.11, 95% CI:0.95-1.3, p = 1.35, I2 = 0%), and smoking (OR = 0.99, 95% CI:0.87-1.13, p = 0.86, I2 = 0%). Meta-regression found that diabetes and hypertension, but not age, significantly moderated the association between NLR and CI. Conclusion: This meta-analysis showed a significant association between high NLR and increased CI risk. Moreover, meta-regression identified diabetes and hypertension, but not age, as significant moderating factors in the relationship between NLR and CI. To validate and strengthen these findings, further large-scale studies are required. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023430384, identifier CRD42023430384.

Impact of prior bariatric surgery on risk and severity of COVID-19 infection: A meta-analysis of observational studies.

BACKGROUND: The association of prior bariatric surgery (BS) with infection rate and prognosis of coronavirus disease 2019 (COVID-19) remains unclear. We conducted a meta-analysis of observational studies to address this issue. METHODS: We searched databases including MEDLINE, Embase, and CENTRAL from inception to May, 2022. The primary outcome was risk of mortality, while secondary outcomes included risk of hospital/intensive care unit (ICU) admission, mechanical ventilation, acute kidney injury (AKI), and infection rate. RESULTS: Eleven studies involving 151,475 patients were analyzed. Meta-analysis showed lower risks of mortality [odd ratio (OR)= 0.42, 95% CI: 0.27-0.65, p < 0.001, I2 = 67%; nine studies; 151,113 patients, certainty of evidence (COE):moderate], hospital admission (OR=0.56, 95% CI: 0.36-0.85, p = 0.007, I2 =74.6%; seven studies; 17,810 patients; COE:low), ICU admission (OR=0.5, 95% CI: 0.37-0.67, p < 0.001, I2 =0%; six studies; 17,496 patients, COE:moderate), mechanical ventilation (OR=0.52, 95% CI: 0.37-0.72, p < 0.001, I2 =57.1%; seven studies; 137,992 patients, COE:moderate) in patients with prior BS (BS group) than those with obesity without surgical treatment (non-BS group). There was no difference in risk of AKI (OR=0.74, 95% CI: 0.41-1.32, p = 0.304, I2 =83.6%; four studies; 129,562 patients, COE: very low) and infection rate (OR=1.05, 95% CI: 0.89-1.22, p = 0.572, I2 =0%; four studies; 12,633 patients, COE:low) between the two groups. Subgroup analysis from matched cohort studies demonstrated associations of prior BS with lower risks of mortality, ICU admission, mechanical ventilation, and AKI. CONCLUSION: Our results showed a correlation between prior BS and less severe COVID-19, which warrants further investigations to verify.

Prophylactic effect of intravenous lidocaine against cognitive deficit after cardiac surgery: A PRISMA-compliant meta-analysis and trial sequential analysis.

BACKGROUND: This study aimed at providing an updated evidence of the association between intraoperative lidocaine and risk of postcardiac surgery cognitive deficit. METHODS: Randomized clinical trials (RCTs) investigating effects of intravenous lidocaine against cognitive deficit in adults undergoing cardiac surgeries were retrieved from the EMBASE, MEDLINE, Google scholar, and Cochrane controlled trials register databases from inception till May 2021. Risk of cognitive deficit was the primary endpoint, while secondary endpoints were length of stay (LOS) in intensive care unit/hospital. Impact of individual studies and cumulative evidence reliability were evaluated with sensitivity analyses and trial sequential analysis, respectively. RESULTS: Six RCTs involving 963 patients published from 1999 to 2019 were included. In early postoperative period (i.e., 2 weeks), the use of intravenous lidocaine (overall incidence = 14.8%) was associated with a lower risk of cognitive deficit compared to that with placebo (overall incidence = 33.1%) (relative risk = 0.49, 95% confidence interval: 0.32-0.75). However, sensitivity analysis and trial sequential analysis signified insufficient evidence to arrive at a firm conclusion. In the late postoperative period (i.e., 6-10 weeks), perioperative intravenous lidocaine (overall incidence = 37.9%) did not reduce the risk of cognitive deficit (relative risk = 0.99, 95% confidence interval: 0.84) compared to the placebo (overall incidence = 38.6%). Intravenous lidocaine was associated with a shortened LOS in intensive care unit/hospital with weak evidence. CONCLUSION: Our results indicated a prophylactic effect of intravenous lidocaine against cognitive deficit only at the early postoperative period despite insufficient evidence. Further large-scale studies are warranted to assess its use for the prevention of cognitive deficit and enhancement of recovery (e.g., LOS).

Impact of combined epidural anaesthesia/analgesia on postoperative cognitive impairment in patients receiving general anaesthesia: a meta-analysis of randomised controlled studies.

BACKGROUND: To investigate the efficacy of combined epidural anaesthesia/analgesia (EAA) against postoperative delirium/cognitive dysfunction (POD/POCD) in adults after major non-cardiac surgery under general anaesthesia (GA). METHODS: The databases of PubMed, Google Scholar, Embase and Cochrane Central Register were searched from inception to November 2021 for available randomised controlled trials (RCTs) that assessed the impact of EAA on risk of POD/POCD. The primary outcome was risk of POD/POCD, while the secondary outcomes comprised postoperative pain score, length of hospital stay (LOS), risk of complications, and postoperative nausea/vomiting (PONV). RESULTS: Meta-analysis of eight studies with a total of 2376 patients (EAA group: 1189 patients; non-EAA group: 1187 patients) revealed no difference in risk of POD/POCD between the EAA and the non-EAA groups [Risk ratio (RR): 0.68; 95% CI: 0.41 to 1.13, p = 0.14, I2 = 73%], but the certainty of evidence was very low. Nevertheless, the EAA group had lower pain score at postoperative 24 h [mean difference (MD): -1.49, 95% CI: -2.38 to -0.61; I2 = 98%; five RCTs; n = 476] and risk of PONV (RR = 0.73, 95% CI: 0.57 to 0.93, p = 0.01, I2 = 0%; three RCTs, 1876 patients) than those in the non-EAA group. Our results showed no significant impact of EAA on the pain score at postoperative 36-72 h, LOS, and risk of complications. CONCLUSION: This meta-analysis demonstrated that EAA had no significant impact on the incidence of POD/POCD in patients following non-cardiac surgery.

Efficacy of high flow nasal oxygenation against hypoxemia in sedated patients receiving gastrointestinal endoscopic procedures: A systematic review and meta-analysis.

STUDY OBJECTIVE: To evaluate the impact of high flow nasal oxygenation (HFNO) on the risk of hypoxemia during gastrointestinal endoscopic procedures (GEPs) under sedation. DESIGN: Meta-analysis of randomized controlled trials. SETTING: Gastrointestinal endoscopy. INTERVENTION: HFNO. PATIENTS: Adults patients undergoing GEPs under sedation. MEASUREMENTS: The primary outcome was risk of hypoxemia, while the secondary outcomes included risks of severe hypoxemia, hypercapnia, need for jaw thrust or other airway interventions, and procedural interruption as well as procedure time, minimum SpO2, and level of carbon dioxide (CO2). Analyses based on age, gender, flow rate, risk status of patients were performed to investigate subgroup effects. RESULTS: Medline, Google scholar, Cochrane Library, and EMBASE databases were searched from inception to July 2021. Seven randomized controlled trials (RCTs) involving 2998 patients published from 2019 to 2021 were included. All GEPs were performed under propofol sedation. Pooled results revealed significantly lower risks of hypoxemia [relative risk (RR) = 0.31, 95% CI:0.13-0.75; 2998 patients], severe hypoxemia (RR = 0.38, 95% CI:0.2-0.74; 2766 patients), other airway interventions (RR = 0.34, 95% CI:0.22-0.52; 2736 patients), procedural interruption (RR = 0.12, 95% CI:0.02-0.64, 451 patients) and a lower CO2 level [standard mean difference (MD) = -0.21, 95% CI: -0.4 to -0.03; 458 patients] in HFNO group compared to control group. Subgroup analysis focusing on risk of hypoxemia showed no significant subgroup effects, indicating consistent benefits of HFNO in different clinical settings. There were no difference in minimum SpO2 (p = 0.06; 262 patients), risk of hypercapnia (p = 0.09; 393 patients), need for jaw thrust (p = 0.28; 2256 patients), and procedure time (p = 0.41, 1004 patients) between the two groups. CONCLUSION: Our results demonstrated the efficacy of high flow nasal oxygenation for reducing the risk of hypoxemia in patients receiving elective gastrointestinal endoscopic procedures under sedation. Further studies are warranted to verify its cost-effectiveness in the gastrointestinal endoscopy setting.

Impact of intravenous and topical lidocaine on clinical outcomes in patients receiving propofol for gastrointestinal endoscopic procedures: a meta-analysis of randomised controlled trials.

BACKGROUND: The efficacy of i.v. or topical lidocaine as an anaesthesia adjunct in improving clinical outcomes in patients receiving gastrointestinal endoscopic procedures under propofol sedation remains unclear. METHODS: Electronic databases (MEDLINE, EMBASE, and Cochrane Library) were searched for RCTs comparing the clinical outcomes with or without lidocaine application (i.v. or topical) in patients receiving propofol for gastrointestinal endoscopic procedures from inception to 29 March 2021. The primary outcome was propofol dosage, while secondary outcomes included procedure time, recovery time, adverse events (e.g. oxygen desaturation), post-procedural pain, and levels of endoscopist and patient satisfaction. RESULTS: Twelve trials (1707 patients) published between 2011 and 2020 demonstrated that addition of i.v. (n=7) or topical (n=5) lidocaine to propofol sedation decreased the level of post-procedural pain (standardised mean difference [SMD]=-0.47, 95% confidence interval [CI]: -0.8 to -0.14), risks of gag events (risk ratio [RR]=0.51, 95% CI: 0.35-0.75), and involuntary movement (RR=0.4, 95% CI: 0.16-0.96). Subgroup analysis demonstrated that only i.v. lidocaine reduced propofol dosage required for gastrointestinal endoscopic procedures (SMD=-0.83, 95% CI: -1.19 to -0.47), increased endoscopist satisfaction (SMD=0.75, 95% CI: 0.21-1.29), and shortened the recovery time (SMD=-0.83, 95% CI: -1.45 to -0.21). Intravenous or topical lidocaine did not affect the incidence of oxygen desaturation (RR=0.72, 95% CI: 0.41-1.24) or arterial hypotension (RR=0.6, 95% CI: 0.22-1.65) and procedure time (SMD=0.21, 95% CI: -0.09 to 0.51). CONCLUSION: This meta-analysis demonstrated that i.v. or topical lidocaine appears safe to use and may be of benefit for improving propofol sedation in patients undergoing gastrointestinal endoscopic procedures. Further large-scale trials are warranted to support our findings.

Association of preoperative prognostic nutritional index with risk of postoperative delirium: A systematic review and meta-analysis.

Study objective: To assess the association between prognostic nutritional index (PNI) and risk of postoperative delirium (POD) in adult patients. Methods: MEDLINE, Google scholar, EMBASE, and Cochrane library databases were searched from inception till April 2022. The primary outcome was the association between PNI and the risk of POD, while the secondary outcomes were correlations of other prognostic factors with POD risk. The correlation between PNI and the incidence of POD was assessed with three approaches: Difference in preoperative PNI between POD and non-POD groups (Model 1) as well as the association of PNI as a continuous parameter (Model 2) or as a binary variable (i.e., low vs. high using a PNI cut-off value of 50) (Model 3) with POD risk. Results: Analysis of nine observational studies published from 2010 to 2021 recruiting 3,743 patients showed a POD incidence of 6.4-35%. Our meta-analysis demonstrated a lower PNI among patients in the POD group (MD: -3.78, 95% CI: -4.85 to -2.71, p < 0.0001, I 2 = 54.2%) compared to the non-POD group (Model 1). Pooled results revealed a negative association between PNI and POD risk for both Model 2 (OR: 0.91, 95% CI: 0.86-0.97, p = 0.002, I 2 = 71%) and Model 3 (OR: 1.68, 95% CI: 1.26-2.23, p < 0.0001, I 2 = 0%). Besides, while our results supported an age-dependent increase in POD risk, other factors including body-mass index, surgical time, health status, hypertension, diabetes mellitus, and male gender were non-significant predictors of POD. Conclusion: Our results demonstrated a negative association between PNI and POD, which warrant further large-scale studies for validation. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022323809.

A Case Report of an Incidental Ultrasound Finding in a Suspected Malignant Hyperthermia Patient.

Malignant hyperthermia (MH) is a rare but life-threatening genetic disorder of the skeletal muscles triggered by inhalation anesthetics or succinylcholine. A 49-year-old female developed symptoms of MH shortly after a lumbar surgery. Despite being insidious, MH was diagnosed based on the clinical grading scale. We incidentally discovered fine fasciculations in extremities while inserting an ultrasound-guided arterial catheter. On receiving dantrolene, her symptoms improved within 20 minutes; a subsequent ultrasound revealed no fasciculations. Although halothane contracture testing was not available, the fasciculations that resolved with dantrolene administration in a MH suspected patient opens up a new potential avenue of diagnostics.

A meta-analysis of randomized clinical trials on the impact of oral vitamin C supplementation on first-year outcomes in orthopedic patients.

This meta-analysis aimed at investigating the impact of oral vitamin C supplementation on the post-procedural recovery of orthopedic patients, including functional outcomes and complex regional pain syndrome type I (CRPS I). Literature search using the Medline, Cochrane Library, and Embase databases from inception till March 2021 identified seven eligible randomized controlled trials with 1,361 participants. Forest plot revealed no significant difference in the functional outcomes at 6-12 months [standardized mean difference (SMD) = -0.00, 95% CI - 0.19 to 0.18, 467 patients], risk of overall complications (RR = 0.98, 95% CI 0.68 to 1.39, 426 patients), and pain severity at 3-6 months (SMD = - 0.18, 95% CI - 0.49 to 0.12, 486 patients) between patients with and without oral vitamin C supplementation. Pooled analysis showed that vitamin C treatment reduced the risk of CRPS I regardless of dosage (RR = 0.46, 95% CI 0.25 to 0.85, 1143 patients). In conclusion, the current meta-analysis demonstrated that oral vitamin C supplementation may reduce the risk of complex regional pain syndrome type I but did not improve the functional outcomes in orthopedic patients. Nevertheless, because of the small number of trials included in the present study, further large-scale clinical studies are warranted to support our findings.

Myasthenic crisis and late deep vein thrombosis following thymectomy in a patient with myasthenia gravis: A case report.

INTRODUCTION: Surgical stress and pain are potential provoking factors for postoperative myasthenic crisis (POMC). We report the occurrence of early POMC and late deep vein thrombosis (DVT) in a man with myasthenia gravis (MG) undergoing thymectomy, addressing possible link between reversal of opioid overdose with naloxone and the triggering of POMC. PATIENT CONCERNS: A 71-year-old man with impaired renal function (ie, estimated glomerular filtration rate [egfr]: 49.1 mL/min/1.73 m) with diagnosis of MG made 2 months ago was scheduled for thymectomy. After uncomplicated surgery, he experienced opioid overdose that was treated with naloxone. Hyperlactatemia then developed with a concomitant episode of hypertension. Three hours after reversal, he suffered from myasthenic crisis presenting with respiratory failure and difficult weaning from mechanical ventilation. DIAGNOSIS: Stress-induced hyperlactatemia and subsequent myasthenic crisis INTERVENTIONS:: Pyridostigmine and immunosuppressive therapy with prednisolone were initiated. Hyperlactatemia subsided on postoperative day (POD) 5. Tracheal extubation was performed successfully on POD 6. OUTCOMES: During the course of hospitalization, his eGFR (ie, 88.9 mL/min/1.73 m) was found to improve postoperatively. After discharge from hospital, he developed DVT in the left femoral and popliteal veins on POD 24 when he was readmitted for immediate treatment with low-molecular-weight heparin. He was discharged without sequelae on POD 31. There was no recurrence of myasthenic crisis or DVT at 3-month follow-up. CONCLUSIONS: Following naloxone administration, hyperlactatemia may be an indicator of pain-related stress response, which is a potential provoking factor for myasthenic crisis. Additionally, patients with MG may have an increased risk of DVT possibly attributable to immune-mediated inflammation. These findings highlight the importance of perioperative avoidance of provoking factors including monitoring of stress-induced elevations in serum lactate concentration, close postoperative surveying for myasthenic crisis, and early recognition of possible thromboembolic complications in this patient population.

Heart rate variability and surgical pleth index under anesthesia in poor and normal sleepers.

Poor sleep quality is associated with autonomic dysfunctions and altered pain perception and tolerance. To investigate whether autonomic dysregulations related to insomnia would still exist under general anesthesia, we adopt heart rate variability (HRV) analysis to evaluate ANS activity and surgical pleth index (SPI) to compare nociceptive/anti-nociceptive balance. We enrolled 61 adult females scheduled for gynecological surgeries under general anesthesia. All the subjects were ASA Class I to III without using medicines affecting HRV. We used the Insomnia Severity Index to evaluate sleep qualities. ECG data were recorded and signals which denote four different surgical stages were extracted (baseline, incision, mid-surgery, and end of surgery). We analyzed the HRV changes across the whole surgical period and differences among good and poor sleepers. We also compared the SPI differences among groups. For baseline HRV analysis, we found significant differences in the RMSSD (p = 0.043), pNN50 (p = 0.029), VLF power (p = 0.035), LF power (p = 0.004), and HF power (p = 0.037) between the good and poor sleeper groups. However, all intergroup differences disappeared after anesthesia induction. Temporal HRV changes significantly among different perioperative stages (RMSSD, p < 0.001; pNN50, p = 0.004; LF, p < 0.001; and HF, p < 0.001). Patients with different sleep qualities did not exhibit different SPI levels in all four periods. Poor sleepers exhibited attenuated parasympathetic activities at the baseline but no differences after the induction. Nociceptive/anti-nociceptive balance seems not be altered by poor sleep condition under general anesthesia.

Impact of serum uric acid on renal function after bariatric surgery: a retrospective study.

BACKGROUND: Despite a known negative association between serum uric acid level (SUA) and renal function, this correlation in patients after bariatric surgery remains unknown. OBJECTIVE: To assess correlation between postoperative SUA and estimated glomerular filtration rate (eGFR) at 12 months after bariatric surgery. SETTING: A single tertiary referral center. METHODS: A total of 252 patients (age = 40.5 ± 11.2; body mass index = 39.0 ± 5.5 kg/m2) undergoing bariatric surgery divided into 2 groups (i.e., normal renal function [90 ≤ eGFR < 125 mL/min/1.73 m2, n = 176] versus renal function impairment [eGFR < 90 mL/min/1.73 m2, n = 76]) were assessed for relationships between SUA and eGFR in both groups (primary endpoint) and associations of percentage weight loss with changes in SUA (△SUA) and eGFR (△eGFR) for all patients (secondary endpoint) at 12 months. RESULTS: Overall, prevalence of hyperuricemia was 40.4% and 22.2% (baseline and postoperative 12 mo, respectively). Reverse relationship was observed between SUA and eGFR (r = -.152, P = .007) for all patients with no association noted between baseline SUA and eGFR in each group as well as between SUA and eGFR at 12 months in the normal group (r = -.076, P = .437). The reverse relationship was found (r = -.417, P = .005) in renal function impairment group for whom SUA was identified as a predictor of eGFR at 12 months. There was no association of percentage weight loss with △SUA (r = .089, P = .601) and △eGFR (r = -.046, P = .785). CONCLUSION: The results demonstrated a negative relationship between postoperative SUA and renal function in patients with preexisting renal dysfunction undergoing bariatric surgery. Clinical significance of our findings warrants further investigation.

Association of Serum Zinc Concentration with Preservation of Renal Function After Bariatric Surgery: a Retrospective Pilot Study.

BACKGROUND: Although serum zinc level (Zn) is known to impact renal function in patients with diabetes, their correlation following bariatric surgery remains unknown. This study aimed at assessing the association of Zn with estimated glomerular filtration rate (eGFR) after laparoscopic sleeve gastrectomy (LSG). METHODS: One hundred and twenty-nine patients in total (mean age, 38.1 ± 10.8; body mass index, 39.1 ± 5.1 kg/m2) with normal preoperative kidney function undergoing LSG at a single tertiary referral center were reviewed. The primary study endpoint was the relationship between Zn and post-LSG eGFR at 12-month follow-up. The secondary outcomes were the associations of percentage weight loss (%WL) with changes in Zn (△Zn) and eGFR (△eGFR). RESULTS: The incidence of zinc deficiency was 8.5%, 8.1%, and 29.9% at baseline, post-LSG and one- and 12-month follow-up, respectively. At 12-month follow-up, Zn dropped from 104.1 ± 19.2 to 85.3 ± 38.9 µg/dL (p = 0.001), while eGFR levels decreased from 106.6 ± 10.3 to 102.1 ± 19.4 mL/min per 1.73 m2 (p = 0.025). Zn correlated positively with eGFR at 6-month (r = 0.252, p = 0.037) and 12-month (r = 0.41, p = 0.001) follow-ups. Multiple linear regression analyses including baseline variables of age, sex, BMI, %WL, and diabetes identified Zn and %WL as independent predictors of eGFR at 12-month follow-up. There was no evidence of multicollinearity among these variables. Despite positive association between %WL and △eGFR (r = 0.222, p = 0.031), no correlation was noted between %WL and △Zn (r = - 0.129, p = 0.40). CONCLUSION: The results demonstrated a positive relationship between post-LSG serum zinc levels and preservation of renal function among patients with obesity in a surgical setting. Large-scale studies are warranted to support the findings.

Association of preoperative hemoglobin with weight loss after bariatric surgery: a retrospective study.

BACKGROUND: Despite the known positive correlation between exercise and weight loss after bariatric surgery as well as the established association of hemoglobin level with maximal aerobic power and endurance performance, the correlation between preoperative hemoglobin concentration (pre-Hb) and postoperative weight loss remains unknown. OBJECTIVE: This study aimed at assessing the association of pre-Hb with postoperative percentage weight loss (%WL) at 3, 6, 12, and 24 months after surgery. SETTING: A single tertiary referral center. METHODS: Outcomes of 282 patients undergoing laparoscopic sleeve gastrectomy at the 4 timepoints within a 24-month follow-up period were assessed. The primary study endpoint was the relationship between pre-Hb and postoperative %WL at 12-month follow-up. RESULTS: The 282 patients had a mean preoperative body mass index of 39.0 ± 4.5 kg/m2 with a slight female predominance (57.4%). Follow-up data were available for 221 of 282 (78.4%) patients (mean %WL: 30.9% ± 6.6%) at 1 year. Pearson's correlation showed that pre-Hb correlated positively with post-Hb (r = 0.778, P < .001) and %WL (r = .237, P < .001) at 12-month follow-up but not at 24 months (r = .145, P = .331). Multiple linear regression analyses including baseline variables of age, sex, preoperative body mass index, and diabetes revealed that pre-Hb, age, and preoperative body mass index were independent predictors of %WL. There was no evidence of multicollinearity among these variables. CONCLUSION: The present study showed a potential positive relationship between pre-Hb and postoperative weight loss. More well-designed, large-scale studies are warranted to clarify the effect of hemoglobin level on postoperative weight loss in this patient population.

Successful endotracheal intubation with Trachway after failed fiber-optic manipulations in a patient with retropharyngeal cervical chordoma.

A retropharyngeal mass may distort the airway anatomy and reduce the space available for manipulation of intubation devices. We encountered a patient with a cervical chordoma occupying the retropharyngeal space. Fiber-optic orotracheal intubation was attempted to secure the airway. Although the fiber-optic bronchoscope (FOB) was successfully placed into the trachea, the tracheal tube could not be passed through the glottis. An airway was then successfully established with the Trachway device, a video-assisted system with a rigid but malleable intubating stylet. In conclusion, although a FOB is commonly used to secure a difficult airway, the present case report demonstrates that fiber-optic intubation is not always successful. Video intubation devices with a rigid stylet (such as Trachway) may be helpful in patients with a cervical chordoma. We suggest this device be available as backup for patients with distorted airway anatomy.

Difficult weaning from mechanical ventilator in a patient with corticosteroid insufficiency after low anterior resection of sigmoid colon.

A 75-year-old man underwent low anterior resection for sigmoid colon cancer under general anesthesia. Comprehensive preoperative surveys showed normal cardiopulmonary functions. In spite of adequate fluid administration, persistent intraoperative hypotension required vasopressors to maintain an acceptable blood pressure. Although the patient was fully awakened from anesthesia with adequate oxygenation, repeated attempts to wean him from the ventilator failed in the postanesthesia intensive care unit, despite recovery from the effect of muscle relaxant. Low plasma cortisol level was found in a series of laboratory analyses. After supplementation with corticosteroid, the patient was successfully weaned from the mechanical ventilator without any sequelae.