Thoracic epidural analgesia (TEA) and transversus abdominis plane (TAP) block are used for pain control after abdominal surgery. Although there have been several meta-analyses comparing these two techniques, the conclusion was limited by a small number of studies and heterogeneity among studies. Our meta-analysis used the Medline, EMBASE, and Cochrane central library databases from their inception through September 2022. Randomized controlled trials (RCTs) comparing TEA and TAP block were included. The pre-specified primary outcome was the pain score at rest at 12 h postoperatively. Twenty-two RCTs involving 1975 patients were included. Pooled analyses showed the pain score at rest at 12 h postoperatively was significantly different between groups favoring TEA group (Mean difference [MD] 0.58, 95% confidence interval CI − 0.01, 1.15, P = 0.04, I2 = 94%). TEA group significantly reduced the pain score at 48 h at rest (MD 0.59, 95% CI 0.15, 1.03, P = 0.009, I2 = 86%) and at 48 h at movement (MD 0.53, 95% CI 0.07, 0.99, P = 0.03, I2 = 76%). However, there was no significant difference at other time points. Time to ambulation was shorter in TAP block but the incidence of hypotension at 24 h and 72 h was significantly lower in TAP block compared to TEA. Trial sequential analysis showed that the required information size has not yet been reached. Our meta-analysis demonstrated there was no significant or clinically meaningful difference in the postoperative pain scores between TEA and TAP block group. Given the insufficient information size revealed by TSA, the high risk of bias of our included studies, and the significant heterogeneity of our meta-analysis results, our results should be interpreted carefully but it is not likely that the addition of further studies could prove any clinically meaningful difference in pain score between these two techniques.

Early allograft dysfunction (EAD) and acute kidney injury (AKI) are common and clinically important complications after liver transplantation. Serum lactate level at the end of surgery could predict EAD and neutrophil gelatinase-associated lipocalin (NGAL) is known as a biomarker for AKI after liver transplantation. The authors investigated whether the combination of these two laboratory tests could be used as an early predictor of these two complications of EAD and AKI. We reviewed cases undergoing living donor liver transplantation (n = 353). Lactate-adjusted NGAL level, a combination of these two predictors, was calculated as the sum of each value multiplied by the odds ratio for EAD or AKI. We evaluated whether this combined predictor at the end of surgery is significantly associated with both postoperative AKI or EAD. We compared the area under the receiver operating characteristic curve (AUC) between our multivariable regression models with and without NGAL, lactate, or lactate-adjusted NGAL. NGAL, lactate and lactate-adjusted NGAL are significant predictors for EAD and AKI. The regression model for EAD or AKI including lactate-adjusted NGAL showed a greater AUC (for EAD: odds ratio [OR] 0.88, 95% confidence interval [CI] 0.84–0.91; for AKI: OR 0.89, 95% CI 0.85–0.92) compared to the AUC of the models including lactate (for EAD: OR 0.84, 95% CI 0.81–0.88; for AKI: OR 0.79, 95% CI 0.74–0.83) or NGAL alone (for EAD: OR 0.82, 95% CI 0.77–0.86; for AKI: OR 0.84, 95% CI 0.80–0.88) or the model without lactate or NGAL (for EAD: OR 0.64, 95% CI 0.58–0.69, for AKI: OR 0.75, 95% CI 0.70–0.79). In conclusion, lactate-adjusted NGAL level at the end of surgery could be a reliable combined laboratory predictor for postoperative EAD or AKI after liver transplantation with a greater discriminative ability than lactate or NGAL alone.

Emergency abdominal surgery has high rates of mortality and morbidity. However, perioperative strategies to mitigate adverse outcomes are not well established yet. Given the frequent comorbidities and pathophysiology of these patients, the incidence of acute kidney injury (AKI) could be high. Therefore, we aimed to investigate the incidence and prognosis of AKI and potentially modifiable risk factors of AKI after emergency abdominal surgery. We retrospectively reviewed consecutive patients who underwent emergency open abdominal surgery at a single tertiary care university hospital. The overall incidence of AKI was 20.3% (n = 96). Postoperative AKI is significantly associated with clinical outcomes including admission to ICU, length of hospital and ICU stay, and in-hospital mortality. Multivariable logistic regression analysis for postoperative AKI revealed that age, body-mass index and ASA classification class 3 or 4 versus 2 were significant predictors. Furthermore, intraoperative vasopressin infusion (odds ratio 4.06, 95% confidence interval [CI] 1.19–13.9), preoperative platelet count (odds ratio 0.72, 95% CI 0.57–0.90, p = 0.003) and maximal serum lactate level (and odds ratio 1.14, 95% CI 1.04–1.26, p = 0.006) were identified as potentially modifiable risk factors. Further prospective clinical trials are required to investigate whether modification of these risk factors could mitigate the risk of AKI.