Open datasets in perioperative medicine: a narrative review

With the growing interest of researchers in machine learning and artificial intelligence (AI) based on large data, their roles in medical research have become increasingly prominent. Despite the proliferation of predictive models in perioperative medicine, external validation is lacking. Open datasets, defined as publicly available datasets for research, play a crucial role by providing high-quality data, facilitating collaboration, and allowing an objective evaluation of the developed models. Among the available datasets for surgical patients, VitalDB has been the most widely used, with the Medical Informatics Operating Room Vitals and Events Repository recently launched and the Informative Surgical Patient dataset for Innovative Research Environment expected to be released soon. For critically ill patients, the available resources include the Medical Information Mart for Intensive Care, the eICU Collaborative Research Database, the Amsterdam University Medical Centers Database, and the High time Resolution ICU Dataset, with the anticipated release of the Intensive Care Network with Million Patients' information for the AI Clinical decision support system Technology dataset. This review presents a detailed comparison of each to enrich our understanding of these open datasets for data science and AI research in perioperative medicine

The EC90 of remifentanil for blunting cardiovascular responses to head fixation for neurosurgery under total intravenous anesthesia with propofol and remifentanil based on bispectral index monitoring: estimation with the biased coin up-and-down sequential method

Abstract Background Head fixation can induce hemodynamic instability. Remifentanil is commonly used with propofol for total intravenous anesthesia (TIVA) during neurosurgery. This study investigated the 90% effective concentration (EC90) of remifentanil for blunting of cardiovascular responses to head fixation during neurosurgery via bispectral index (BIS) monitoring. Methods Fifty patients undergoing neurosurgery requiring head fixation were enrolled. This study was performed using the biased coin up-and-down design sequential method (BCD). After tracheal intubation, the effect-site target concentration (Ce) of remifentanil was adjusted to achieve hemodynamic stability and reset to the level preoperatively assigned to each patient, according to the BCD method, approximately 10 min before head fixation. Baseline hemodynamic values were recorded before head fixation. An ineffective response was defined as a case with a > 20% increase in hemodynamic values from baseline. Otherwise, the response was determined to be effective. The EC90 of remifentanil was calculated as a modified isotonic estimator. Results Forty-three patients completed this study. The EC90 of remifentanil for blunting cardiovascular responses to head fixation was estimated to be 6.48 ng/mL (95% CI, 5.94–6.83 ng/mL). Conclusions Adjustment of the Ce of remifentanil to approximately 6.5 ng/mL before head fixation could prevent noxious cardiovascular responses in 90% of neurosurgical ASA I-II patients aged 20 to 65 years old during propofol target-controlled infusion titrated to maintain BIS between 40 and 50. Trial registration ClinicalTrials.gov Identifier NCT01489137 , retrospectively registered 5 December 2011

Intraoperative Oliguria with Decreased SvO2 Predicts Acute Kidney Injury after Living Donor Liver Transplantation

Acute kidney injury (AKI) is a frequent complication after living donor liver transplantation (LDLT), and is associated with increased mortality. However, the association between intraoperative oliguria and the risk of AKI remains uncertain for LDLT. We sought to determine the association between intraoperative oliguria alone and oliguria coupled with hemodynamic derangement and the risk of AKI after LDLT. We evaluated the hemodynamic variables, including mean arterial pressure, cardiac index, and mixed venous oxygen saturation (SvO2). We reviewed 583 adult patients without baseline renal dysfunction and who did not receive hydroxyethyl starch during surgery. AKI was defined using the Kidney Disease Improving Global Outcomes criteria according to the serum creatinine criteria. Multivariable logistic regression analysis was performed with and without oliguria and oliguria coupled with a decrease in SvO2. The performance was compared with respect to the area under the receiver operating characteristic curve (AUC). Intraoperative oliguria <0.5 and <0.3 mL/kg/h were significantly associated with the risk of AKI; however, their performance in predicting AKI was poor. The AUC of single predictors increased significantly when oliguria was combined with decreased SvO2 (AUC 0.72; 95% confidence interval (CI) 0.68–0.75 vs. AUC of oliguria alone 0.61; 95% CI 0.56–0.61; p < 0.0001; vs. AUC of SvO2 alone 0.66; 95% CI 0.61–0.70; p < 0.0001). Addition of oliguria coupled with SvO2 reduction also increased the AUC of multivariable prediction (AUC 0.87; 95% CI 0.84–0.90 vs. AUC with oliguria 0.73; 95% CI 0.69–0.77; p < 0.0001; vs. AUC with neither oliguria nor SvO2 reduction 0.68; 95% CI 0.64–0.72; p < 0.0001). Intraoperative oliguria coupled with a decrease in SvO2 may suggest the risk of AKI after LDLT more reliably than oliguria alone or decrease in SvO2 alone. Intraoperative oliguria should be interpreted in conjunction with SvO2 to predict AKI in patients with normal preoperative renal function and who did not receive hydroxyethyl starch during surgery

Efficacy of nutritional support protocol for patients with pressure ulcer: comparison of before and after the protocol

Objectives: Because most patients who develop pressure ulcer (PU) are malnourished, additional nutritional support is important for PU improvement. The aim of this study was to investigate the potential benefit of a simple nutritional support protocol in PU improvement. Methods: This study was a comparative before-and-after study, prospectively performed from May to December 2020. Participants were inpatients of Seoul National University Hospital (SNUH), South Korea. Among the patients who developed PU from May to December 2020, those on enteral nutrition were included in the protocol group. Application of the nutritional support protocol was established in May 2020 in SNUH. Serum levels of prealbumin, transferrin, cholesterol, and zinc were measured initially and 2 and 4 wk after protocol application to evaluate clinical course. A tailored regimen that adjusted the amount of protein and trace elements was provided according to consultation with the nutritional support team. Size and Pressure Ulcer Scale for Healing was evaluated every 2 wk by the same nurse in charge of PU. To validate the efficacy of the protocol, patients who developed PU from May to December 2018, were hospitalized for 2 wk, and who received enteral nutrition were selected as a control group. Results: Sixty-one patients were included in the protocol group and 100 were in the control group. The protocol group had a higher proportion of PU improvement (85.2 versus 50%; P < 0.001), daily protein intake (1.6 ?? 3.2 versus 0.9 ?? 0.4; P = 0.048), Braden scale (12.9 ?? 1.8 versus 12.3 ?? 1.8; P = 0.025), and baseline albumin level (3.1 ?? 0.5 versus 2.8 ?? 0.4; P = 0.001) when compared with the control group. Multivariate analysis showed that implementation of the nutritional support protocol was the most effective factor in improving PU (odds ratio, 0.18; 95% confidence interval, 0.089-0.366; P < 0.001). Conclusions: A simple nutritional support protocol was easy to develop and its application contributed significantly to the recovery of PU.N