Koichi Suehiro

Background: Intraoperative hypotension is associated with postoperative acute kidney injury (AKI), but the optimal intraoperative blood pressure target for patients with hypertension remains uncertain. The authors hypothesized that individualized blood pressure management based on each patient’s preoperative baseline blood measure would reduce the incidence of postoperative AKI compared with standard blood pressure management. Methods: In this randomized clinical trial, the authors enrolled adult patients with a history of hypertension scheduled for elective major abdominal surgery expected to last more than 3 h. Patients were randomly assigned in a 1:1 ratio to individualized or standard intraoperative blood pressure management. In the individualized group, anesthesiologists targeted a mean arterial pressure (MAP) within ±10% of the preoperative baseline MAP; in the standard group, MAP was maintained at 65 mmHg or higher. The primary outcome was the incidence of AKI within 7 days after surgery. Secondary outcomes included the incidence of AKI (stage 2 or greater), initiation of renal replacement therapy, and an ordinal analysis of AKI severity. Results: Of the 400 randomized patients, 381 were included in the final analysis (191 individualized, 190 standard). Intraoperative MAP was higher in the individualized group (84 [79 to 89] vs. 78 [74 to 83] mmHg; P < 0.0001), and the cumulative duration of MAP less than 65 mmHg was shorter (10 [3 to 28] vs. 27 [9 to 64] min; P < 0.0001). Postoperative AKI occurred in 25 of 191 patients (13.1%) in the individualized group and 29 of 190 patients (15.3%) in the standard group (risk ratio: 0.85; 95% CI: 0.52 to 1.41; P = 0.543). Secondary renal outcomes did not differ significantly between groups. Conclusions: In patients with treated hypertension and preserved renal function undergoing prolonged elective abdominal surgery, individualized intraoperative blood pressure management increased MAP and reduced intraoperative hypotension but did not reduce the incidence or severity of postoperative AKI compared with standard blood pressure management.

Background: It is controversial whether hydrogen (H ₂ ) gas can activate cellular survival cascades and autophagy in the myocardium. This translational study aimed to investigate the hypothesis that preconditioning with inhaled H ₂ gas had a cardio-protective effect mediated through the activation of cellular signaling cascades and autophagy. Methods: Rat cardiomyocytes were isolated following 3% H ₂ gas inhalation for 60 min and were then incubated in a solution with or without 10 μM of 3-methyladenine (MA), an autophagy inhibitor. Intracellular Ca ²⁺ concentration after 10-min perfusion of hydrogen peroxide, Ca ²⁺ mobilization from the endoplasmic reticulum (ER), and opening of the mitochondrial permeability transition pore (MPTP) were estimated using fluorescence imaging. The expressions of extracellular signal-regulated kinase (ERK) and Akt and the levels of mitochondrial membrane potentials (ψm) were determined using flow cytometry. Furthermore, autophagosomes and microtubule-associated light chain (LC) 3-II were estimated using for autophagy activation flow cytometry. Results: H ₂ gas inhalation effectively inhibited the increase in the intracellular Ca ²⁺ concentration and Ca ²⁺ mobilization from the ER. The inhibitory effects of H ₂ gas were completely abolished by pretreatment with 3-MA. H ₂ gas inhalation also prolonged the time to MPTP opening, which was considerably shortened by the 3-MA pretreatment. The expression of signaling molecules and the levels of ψm decreased after 1.8 mM Ca ²⁺ stimulation. Regardless of the stimulation, H ₂ gas inhalation preserved the ERK expression and ψm levels and increased autophagosomes and the LC3-II expression, but it did not affect the Akt expression. The 3-MA pretreatment completely abolished the cardio-protective effects of H ₂ gas as well as the autophagy activation. Conclusions: Preconditioning with H ₂ gas confers the cardio-protective effect in association with the activation of the mitogen-activated protein kinase/ERK pathway and autophagy in the myocardium. Thus, it may be feasible and effective as preventive intervention in patients undergoing cardiac surgery.

Background: Esophagectomy for esophageal cancer is complex and frequently complicated by pulmonary issues, cardiac problems, and anastomotic leakage. While numerous factors contribute to these complications, the specific effects of intraoperative hypotension (IOH) on postoperative outcomes remain poorly understood. This study examined the relationship between IOH severity during esophagectomy and subsequent complications. Methods: This retrospective observational study analyzed patients undergoing elective open transthoracic or thoraco-laparoscopic esophagectomy for esophageal cancer between May 2007 and February 2020. Multiple logistic regression assessed IOH’s association with primary outcomes (composite of major complications including 30-day mortality, reoperation, anastomotic leakage, pneumonia, reintubation, and prolonged ventilation > 48 h) and secondary outcomes of anastomotic leakage. Additionally, Cox regression analyzed IOH’s impact on long-term prognosis. Results: The final cohort comprised 884 patients. The most prevalent postoperative complications were anastomotic leakage (25.2%) and pneumonia (23.4%). The 30-day mortality rate was 0.8%. No significant association existed between IOH and major composite outcomes across mean blood pressure (MBP) and systolic blood pressure thresholds. However, IOH was significantly associated with anastomotic leakage when MBP fell below 65 mmHg for extended periods (adjusted odds ratio: 1.02 per 10-min interval, 95% confidence interval: 1.01–1.04, P = 0.01). IOH did not significantly affect long-term survival. Conclusions: This study did not identify a significant association between intraoperative hypotension and composite major postoperative complications or long-term survival outcomes. However, intraoperative hypotension, specifically prolonged episodes with mean blood pressure below 65 mmHg, was significantly associated with the short-term complication of anastomotic leakage. Trial registration: UMIN Clinical Trials Registry, UMIN000040455. Registered 28 May 2020, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000046165 .

Background/Objective: The endothelial glycocalyx is a gel-like layer on the vascular endothelial surface that is crucial for maintaining vascular homeostasis. Massive bleeding leads to the shedding of the glycocalyx, which can lead to vascular leakage during fluid administration. Recently, the beneficial effect of hydrogen inhalation in the treatment of hemorrhagic shock has been reported. However, the efficacy of hydrogen-rich saline in protecting the glycocalyx remains unclear. In this study, we investigated the effects of hydrogen-rich saline on glycocalyx degeneration. Methods: Rats under general anesthesia were divided into five groups: the sham, hemorrhagic shock, normal saline, colloid solution, and hydrogen-rich saline groups (n = 6 for each group). Blood was withdrawn, and blood pressure was maintained at 30–35 mmHg for 60 min. After inducing hemorrhagic shock in this way, each infusion product was administered intravenously to maintain blood pressure at 80 mmHg for 60 min. Glycocalyx thickness was assessed using the GlycoCheck system. Results: The use of hydrogen-rich saline significantly improved the survival rate (p < 0.05), and glycocalyx degeneration was significantly suppressed (p < 0.001), indicating the protective effect of hydrogen on the glycocalyx. Conclusion: Intravenous administration of hydrogen-rich saline in hemorrhagic shock attenuates glycocalyx degeneration compared to conventional fluid resuscitation, which can improve survival rates.

Purpose Prone position has recently gained renewed importance as a treatment for acute respiratory distress syndrome and spine and brain surgeries. Our study aimed to perform an error grid analysis to examine the clinical discrepancies between arterial blood pressure (ABP) and non-invasive blood pressure (NIBP) in the prone position and to investigate the risk factors influencing these differences. Methods Error grid analysis was performed retrospectively on 1389 pairs of 100 consecutive prone positioning cases. This analysis classifies the difference between the two methods into five clinically relevant zones, from “no risk” to “dangerous risk”. Additionally, multivariable ordinal logistic regression analysis was conducted to evaluate the relationship between the risk zones of mean blood pressure (MBP), as classified by error grid analysis and the covariate of interest. Results Error grid analysis showed that the proportions of measurement pairs in risk zones A–E for systolic blood pressure were 96.8%, 3.2%, 0.1%, 0%, and 0%, respectively. In contrast, the MBP proportions were 74.0%, 25.1%, 0.9%, 0.1%, and 0%. Multivariable ordinal logistic regression analysis revealed that the position of arms (next to the head) was a significant factor (adjusted odds ratio: 4.35, 95% CI: 2.38–8.33, P < 0.001). Conclusion Error grid analysis revealed a clinically unacceptable discrepancy between ABP and NIBP for MBP during prone positioning surgery. The position of the arms next to the head was associated with increased clinical discrepancy between the two MBP measurement methods.

Purpose Spinal anesthesia is a standard technique for cesarean delivery; however, it possesses a risk of hypotension. We hypothesised that the changes in the corrected flow time induced by the Trendelenburg position could predict the incidence of hypotension after spinal anesthesia for cesarean delivery. Methods Patients undergoing elective cesarean delivery under spinal anesthesia were enrolled. Before anesthesia induction, corrected flow time was measured in the supine and Trendelenburg positions (FTc-1 and FTc-2, respectively). Additionally, a percent change in corrected flow time induced by the Trendelenburg position was defined as ΔFTc. The primary endpoint was to investigate the ability of ΔFTc to predict the incidence of spinal anesthesia-induced hypotension until delivery. The receiver operating characteristics curves to assess the ability of FTc-1, FTc-2, and ΔFTc to predict the incidence of hypotension were generated. Results Finally, 40 patients were included, and of those, 26 (65%) developed spinal anesthesia-induced hypotension. The areas under the curve for FTc-1, FTc-2, and ΔFTc were 0.591 (95% CI: 0.424 to 0.743) (P = 0.380), 0.742 (95% CI: 0.579 to 0.867) (P = 0.004), and 0.882 (95% CI: 0.740 to 0.962) (P < 0.001) respectively, indicating ΔFTc as the best predictor among these three parameters. The best threshold for ΔFTc was 6.4% (sensitivity: 80.8% (95% CI: 53.8 to 96.2), specificity: 85.7% (95% CI: 42.9 to 100.0)). Conclusions This study demonstrated that changes in the corrected carotid flow time induced by the Trendelenburg position could serve as a good predictor of spinal anesthesia-induced hypotension for cesarean delivery.