Recovery of cardiac electrophysiological alterations by heart rate complexity based on multiscale entropy following liver transplantation.

Autonomic nervous dysfunction is a known cardiac sequalae in patients with end-stage liver disease and is associated with a poor prognosis. Heart rate analysis using nonlinear models such as multiscale entropy (MSE) or complexity may identify marked changes in these patients where conventional heart rate variability (HRV) measurements do not. To investigate the application of heart rate complexity (HRC) based on MSE in liver transplantation settings. Thirty adult recipients of elective living donor liver transplantation were enrolled. HRV parameters using conventional HRV analysis and HRC analysis were obtained at the following time points: (1) 1 day before surgery, (2) postoperative day (POD) 7, (3) POD 14, (4) POD 90, and (5) POD 180. Preoperatively, patients with MELD score ≥ 25 had significantly lower HRC compared to patients with lower MELD scores. This difference in HRC disappeared by POD 7 following liver transplantation and subsequent analyses at POD 90 and 180 continued to show no significant difference. Our results indicated a significant negative correlation between HRC based on MSE analysis and liver disease severity preoperatively, which may be more sensitive than conventional linear HRV analysis. HRC in patients with MELD score ≧ 25 improved over time and became comparable to those with MELD < 25 as early as in 7 days.

Efficacy and safety of remifentanil for endoscopic ultrasound-guided tissue acquisition: a single center retrospective study.

BACKGROUND: Remifentanil is a rapid onset and rapid recovery opioid. The combination of remifentanil and propofol for deep sedation decreases the incidents of movement, cough, and hiccup. We evaluated the efficacy and safety of remifentanil during endoscopic ultrasound-guided tissue acquisition. METHODS: We retrospectively reviewed patients in whom endoscopic ultrasound-guided tissue acquisition was performed for solid mass lesions of the upper gastrointestinal tract and adjacent organs. All patients were premedicated with midazolam (2 mg), and target-controlled infusion of propofol, opioid, and Bispectral Index (BIS) monitoring were administered as necessary to maintain moderate-to-deep sedation. The opioids used were a bolus of alfentanil or remifentanil infusion. The discharge time, consumption of propofol and opioid, adverse events, diagnostic accuracy, and sensitivity and specificity for malignancy, were compared. RESULTS: Tissue acquisition was achieved in 123 patients (alfentanil group, n = 64; remifentanil group, n = 59). The discharge time of the remifentanil group (16.5 ± 3.2 min) was significantly shorter than that of the alfentanil group (19.0 ± 4.9 min, P = 0.001). The consumption of propofol, adverse events, diagnostic accuracy, sensitivity, and specificity for malignancy in the alfentanil group were not significantly different from those in the remifentanil group. CONCLUSIONS: Use of alfentanil or remifentanil for target-controlled infusion of propofol-BIS monitoring can provide good sedative and diagnostic quality for endoscopic ultrasound-guided tissue acquisition. However, remifentanil resulted in faster recovery than alfentanil.

Long-term outcomes after nonintubated versus intubated thoracoscopic lobectomy for clinical stage I non-small cell lung cancer: A propensity-matched analysis.

BACKGROUND: Nonintubated thoracoscopic lobectomy has been described as a feasible surgical treatment for early-stage lung cancer since 2011. Despite promising perioperative results, studies on tumor recurrence and long-term survival are very limited. This study was aimed to compare outcomes after thoracoscopic lobectomy with versus without intubation for stage I non-small cell lung cancer. METHODS: A retrospective data set including 115 and 155 patients who underwent nonintubated and intubated thoracoscopic lobectomy, respectively, between January 2011 and December 2013 was used to identify matched nonintubated and intubated cohorts (n = 97 per group) using a propensity score matching algorithm that accounted for confounding effects of preoperative patient variables. Primary outcome variables included freedom from recurrence and overall survival. Factors affecting survival were assessed using Cox regression analysis and Kaplan-Meier survival estimates. RESULTS: No perioperative mortality occurred in both groups. At an average follow-up of 74 months, comparing nonintubated thoracoscopic lobectomy with intubated procedure, no differences were observed in recurrence rates (14.4% vs. 25.8%, respectively; p = .057). Furthermore, no significant differences were noted in overall survival (97.9% vs. 93.8%, respectively; p = .144). Nonintubated thoracoscopic lobectomy was not found to be an independent predictor of recurrence (hazard ratio, .53; 95% confidence interval [CI], .28-1.02) or overall survival (hazard ratio, .33; 95% CI, .07-1.61). CONCLUSION: In this propensity-matched comparison, nonintubated thoracoscopic lobectomy was not associated with an increased risk for recurrence and overall survival during the 5-year follow-up. However, more randomized trials should be conducted for further validation of these results.

Target-controlled propofol infusion with or without bispectral index monitoring of sedation during advanced gastrointestinal endoscopy.

BACKGROUND AND AIM: Target-controlled infusion (TCI) uses averaged pharmacokinetic datasets derived from population samples to automatically control the infusion rate. Bispectral index (BIS) technology non-invasively measures levels of consciousness during surgical procedures. We compared the efficacy and safety of propofol TCI with or without BIS monitoring for sedation during advanced gastrointestinal endoscopy. METHODS: This prospective study enrolled 200 patients who were premedicated with midazolam 2 mg and alfentanil 0.4 mg before undergoing advanced gastrointestinal endoscopy. The initial target blood concentration of propofol was set at 1.0 µg/mL, and adjustments of 0.2 µg/mL were made as necessary to maintain moderate-to-deep sedation. Patients were randomized to either the BIS-blind group and evaluated for depth of anesthesia by monitoring scores of 1-2 on the Modified Observer's Assessment of Alertness/Sedation scale (n = 100) or to the BIS-open group and monitored by BIS scores of 60-80 (n = 100). The primary outcome was the total amount of propofol required to maintain anesthesia. Secondary outcomes were sedation-induced adverse events, recovery, and quality of sedation (endoscopist and patient satisfaction). RESULTS: The mean propofol infusion rate was significantly higher in patients not monitored by BIS scores than in those who were (5.44 ± 2.12 vs 4.76 ± 1.84 mg/kg/h; P = 0.016). Levels of satisfaction were higher for endoscopists who used BIS monitoring than in those who did not. CONCLUSIONS: Mean infusion rates were higher in propofol TCI without BIS monitoring compared with propofol TCI with BIS during advanced gastrointestinal endoscopy. Endoscopists expressed satisfaction with BIS monitoring.

Sample entropy analysis of EEG signals via artificial neural networks to model patients' consciousness level based on anesthesiologists experience.

Electroencephalogram (EEG) signals, as it can express the human brain's activities and reflect awareness, have been widely used in many research and medical equipment to build a noninvasive monitoring index to the depth of anesthesia (DOA). Bispectral (BIS) index monitor is one of the famous and important indicators for anesthesiologists primarily using EEG signals when assessing the DOA. In this study, an attempt is made to build a new indicator using EEG signals to provide a more valuable reference to the DOA for clinical researchers. The EEG signals are collected from patients under anesthetic surgery which are filtered using multivariate empirical mode decomposition (MEMD) method and analyzed using sample entropy (SampEn) analysis. The calculated signals from SampEn are utilized to train an artificial neural network (ANN) model through using expert assessment of consciousness level (EACL) which is assessed by experienced anesthesiologists as the target to train, validate, and test the ANN. The results that are achieved using the proposed system are compared to BIS index. The proposed system results show that it is not only having similar characteristic to BIS index but also more close to experienced anesthesiologists which illustrates the consciousness level and reflects the DOA successfully.

Upper airway obstruction after cervical spine fusion surgery: role of cervical fixation angle.

Upper airway obstruction is one of the life-threatening events in cervical spine surgery. The risk is particularly great during the period immediately after operation. We present the case of a 56-year-old female with breast cancer and metastasis to the cervical spine. The surgical procedure involved C2-C3 laminectomy, posterior fixation (C0-C5), and C2 neurectomy. Tracheal extubation was carried out in the intensive care unit, and upper airway obstruction immediately followed. Emergency cricothyrotomy was performed under well-managed ventilation with a laryngeal mask after several failed intubation attempts. Over-flexion of the cervical spine fixation and severe prevertebral soft tissue swelling were the most probable causes of upper airway obstruction. With a well-adjusted angle for fixation of the cervical spine under fluoroscopic guidance before the procedure, such a surgical mishap could be avoided. Reintubation with a fiberscope might be considered first, and sustaining intubation for 2-3 days postoperatively could be safer in such high risk patients.

Successful living-related renal transplantation in a 2-year-old girl weighing less than 10 kilograms.

The success of renal transplantation for infants weighing less than 10 kg is very limited because of graft thrombosis. We report a successful living-related renal transplant in a 2-year-old girl weighing 9.5 kg. Chronic renal failure was diagnosed 1 month before the transplantation. Laparoscopic donor nephrectomy was performed to retrieve the left kidney of her father, a 36-year-old man weighing 70 kg, and the recipient operation was conducted via a right retroperitoneal approach. The right native kidney of the recipient was removed to accommodate the graft kidney during the transplant surgery. The graft renal artery, renal vein, and ureter were anastomosed to the recipient abdominal aorta, inferior vena cava, and bladder, respectively. The abdominal fascial defect was closed with absorbable mesh grafting, and the skin was closed primarily. With intensive fluid therapy and monitoring after reperfusion of the graft kidney, the patient recovered uneventfully and was discharged with an FK506-based immunosuppressive regimen 2 weeks after the operation. Renal function was good, and serum creatinine was 0.5 mg/dL 6 months after the operation.