Efficacy and Safety of Remimazolam Versus Etomidate for Induction of General Anesthesia: Protocol for a Systematic Review and Meta-Analysis.

BACKGROUND: Postinduction hypotension (PIHO) is a hemodynamic abnormality commonly observed during the induction of general anesthesia. Etomidate is considered a safer drug for the induction of anesthesia because it has only minor adverse effects on the cardiovascular and pulmonary systems. Recent evidence indicates that the novel benzodiazepine remimazolam has minimal inhibitory effects on the circulation and respiration. However, the efficacy and safety of remimazolam versus etomidate in the induction of anesthesia are unclear. OBJECTIVE: To further understand the potential of remimazolam in anesthesia induction, it is necessary to design a meta-analysis to compare its effects versus the classic safe anesthetic etomidate. The aim of this study is to determine which drug has more stable hemodynamics and a lower incidence of PIHO. Our study will also yield data on sedation efficiency, time to loss of consciousness, time to awakening, incidence of injection pain, and postoperative nausea and vomiting with the two drugs. METHODS: We plan to search the Web of Science, Cochrane Library, Embase, PubMed, China National Knowledge Infrastructure, and Wanfang databases from the date of their creation until March 31, 2025. The language is limited to English and Chinese. The search terms are "randomized controlled trials," "etomidate," and "remimazolam." The incidence of PIHO is the primary outcome measure. Secondary outcomes include depth of anesthesia after induction, sedation success rate, time to loss of consciousness, hemodynamic profiles, recovery time, incidence of injection pain, and postoperative nausea and vomiting. Reviews, meta-analyses, case studies, abstracts from conferences, and commentaries will not be included. The heterogeneity of the results will be evaluated by sensitivity and subgroup analyses. RevMan software and Stata software will be used for data analysis. We will evaluate the quality of included studies using version 2 of the Cochrane risk-of-bias tool. The confidence of the evidence will be assessed through the Grading of Recommendations, Assessments, Developments, and Evaluations system. RESULTS: The protocol was registered in the international PROSPERO (Prospective Register of Systematic Reviews) registry in November 2023. As of June 2024, we have performed a preliminary article search and retrieval for further review. The review and analyses are expected to be completed in March 2025. We expect to submit manuscripts for peer review by the end of June 2025. CONCLUSIONS: By synthesizing the available evidence and comparing remimazolam and etomidate, we hope to provide valuable insights into the selection of anesthesia-inducing drugs to reduce the incidence of PIHO and improve patient prognosis. TRIAL REGISTRATION: PROSPERO CRD42023463120; https://tinyurl.com/333jb8bm. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/55948.

A Case-based Implementation of Heart Failure Therapies, a Consensus Pathway by the Saudi Heart Failure Working Group.

The implementation of guideline-directed medical therapy (GDMT) in heart failure (HF) has many challenges in real-world clinical practice. The consensus document is written considering the variability of the clinical presentation of HF patients. HF medical therapies need frequent dose adjustment during hospital admission or when patients develop electrolyte imbalance, acute kidney injury, and other acute illnesses. The paper describes clinical scenarios and graphs that will aid the managing physicians in decision-making for HF therapy optimization.

A Low-Volume Epidural Blood Patch for the Treatment of Spontaneous Intracranial Hypotension: A Case Report.

Spontaneous intracranial hypotension (SIH) is a rare neurological syndrome. We report the case of a 47-year-old woman with acute, severe orthostatic headache after surgery, chemotherapy, and radiotherapy for breast cancer. The brain and spine magnetic resonance imaging showed signs of intracranial hypotension. We describe the results of a non-targeted epidural blood patch with 10 mL of the patient's blood administered after unsuccessful conservative treatment. After the procedure, the patient reported gradual headache relief. This effect persisted over one year. The case shows that a single non-targeted low-volume epidural blood patch can be an effective treatment option for a patient with SIH when conservative treatment fails.

Predictive Value of Ultrasound-Measured Quadriceps Depth and Frailty Status for Hypotension in Older Patients Undergoing Reverse Total Shoulder Arthroplasty in the Beach Chair Position under General Anesthesia.

The beach chair position (BCP) is widely used in shoulder surgery; however, it frequently leads to hypotension. Hypotension in BCP is prevalent among older patients who are at risk of secondary complications such as ischemic injuries. Therefore, this prospective study aimed to investigate the association and predictive value of frailty, as assessed by ultrasound-measured quadriceps depth and questionnaire, in patients aged ≥65 years undergoing elective shoulder surgery under general anesthesia. A multivariable logistic regression analysis was performed to identify independent risk factors for hypotension in BCP under general anesthesia. Receiver operating characteristic curves were constructed to assess the predictive values of various parameters. The results indicated that a quadriceps depth < 2.3 cm and BCP for an extended period significantly increased the risk of hypotension. The combined consideration of quadriceps depth < 2.3 cm and frailty demonstrated markedly superior predictive power compared with each factor individually. In conclusion, the study findings facilitate the screening and identification of risk factors for older patients undergoing surgery in BCP, thereby enhancing perioperative management.

Effect of pneumatic leg compression on phenylephrine dose for hypotension prophylaxis via variable rate infusion at cesarean delivery: an unblinded randomized controlled trial.

BACKGROUND: Phenylephrine infusion is recommended to prevent spinal hypotension during cesarean delivery (CD) but may be associated with dose-dependent side effects. We hypothesized that adding intermittent pneumatic compression (IPC) of the lower legs to a variable-rate phenylephrine infusion will reduce the dose of phenylephrine required during CD. METHODS: Seventy-six healthy women undergoing elective CD under combined spinal-epidural anesthesia were randomly assigned to IPC or control groups (n = 38 per group). After spinal anesthesia, IPC of the lower legs was initiated in the IPC group, and all women received a phenylephrine infusion starting at 25 µg·min-1 and increasing by 16.7 µg·min-1 for systolic blood pressure (SAP) < 90% baseline. If hypotension (SAP < 80% baseline) occurred, 100 µg phenylephrine bolus was administered. The primary outcome was the dose of phenylephrine per minute. RESULTS: The dose of phenylephrine per minute (34.4 ±â€¯7.3 µg·min-1 vs. 40.9 ±â€¯9.5 µg·min-1, P = 0.001; mean difference -6.6 µg·min-1, 95% CI -10.5 to -2.7 µg·min-1) and the incidence of hypotension (24% vs. 55%, P = 0.005) were lower in the IPC group than in the control group. There were no significant differences between the two groups in the total dose of phenylephrine (603.2 ±â€¯217.1 µg vs. 706.2 ±â€¯247.5 µg, P = 0.058; mean difference -102.9 µg, 95% CI -209.4 to 3.5 µg), maternal side effects, or neonatal outcomes. CONCLUSIONS: Intermittent pneumatic compression combined with a variable-rate phenylephrine infusion reduced the phenylephrine dose per minute and the incidence of hypotension during CD under spinal anesthesia.

Rapid changes in cerebrovascular compliance during vasovagal syncope.

PURPOSE: The compensatory mechanisms supporting cerebral perfusion throughout head-up tilt (HUT) in patients with vasovagal syncope (VVS) remain unclear. We tested the hypothesis that increased cerebrovascular compliance (Ci) and decreased cerebrovascular resistance (CVR) support cerebral blood velocity (CBV) during pre-syncope in VVS. METHODS: Finger arterial blood pressure (ABP) and right middle cerebral artery blood velocity (CBV) were recorded in 15 individuals diagnosed with VVS (n = 11 female, mean age: 40 ± 16 years, mean body mass index: 24.9 ± 4.0 kg/m2) at supine rest and during HUT (80 degree angle). Individual ABP and CBV waveforms during VVS were input into a modified Windkessel model to calculate Ci and ohmic CVR. Gosling's pulsatility index (Pi; pulse amplitude/mean CBV) was calculated. RESULTS: Diastolic ABP, systolic ABP, mean ABP (72 ± 11 to 51 ± 12 mmHg), and CVR decreased progressively during presyncope (all P ≤ 0.04). As expected, systolic CBV was sustained (all P ≥ 0.29) while diastolic and mean CBV (51 ± 13 to 38 ± 13 mmHg) fell during presyncope (all P ≤ 0.04). Both Ci and Pi increased during presyncope (128 ± 97 and 60 ± 41%, respectively; all P ≤ 0.049) and were positively correlated (R2 = 0.79, P < 0.01). Increased Ci contributed to changes in mean CBV (P < 0.01) but decreased CVR did not (P = 0.28). CONCLUSIONS: These data provide evidence that Ci increases during presyncope in patients with VVS and is likely involved in the maintenance of systolic CBV during a fall in diastolic CBV. However, this regulation is not sufficient to preserve CBV in the presence of such extreme and progressive reductions in ABP.

Continuous Monitoring of Advanced Hemodynamic Parameters during Hemodialysis Demonstrated Early Variations in Patients Experiencing Intradialytic Hypotension.

Intradialytic hypotension (IDH) is a severe complication of hemodialysis (HD) with a significant impact on morbidity and mortality. In this study, we used a wearable device for the continuous monitoring of hemodynamic vitals to detect hemodynamic changes during HD and attempted to identify IDH. End-stage kidney disease patients were continuously monitored 15 min before starting the session and until 15 min after completion of the session, measuring heart rate (HR), noninvasive cuffless systolic and diastolic blood pressure (SBP and DBP), stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR). Data were analyzed retrospectively and included comparing BP measured by the wearable devices (recorded continuously every 5 s) and the cuff-based devices. A total of 98 dialysis sessions were included in the final analysis, and IDH was identified in 22 sessions (22.5%). Both SBP and DBP were highly correlated (r > 0.62, p < 0.001 for all) between the wearable device and the cuff-based measurements. Based on the continuous monitoring, patients with IDH had earlier and more profound reductions in SBP and DBP during the HD treatment. In addition, nearly all of the advanced vitals differed between groups. Further studies should be conducted in order to fully understand the potential of noninvasive advanced continuous monitoring in the prediction and prevention of IDH events.

Dexmedetomidine and surgical field visibility in nasal surgery: A systematic review and meta-analysis.

INTRODUCTION: Nasal and sinus surgery, especially using endoscopy, relies upon adequate haemostasis to be safe and effective. Often other haemostatic methods, such as cautery are not viable, and other methods must be employed. This study examines the effectiveness of dexmedetomidine in controlled hypotension and for surgical field visibility in endoscopic sinus surgery and other nasal surgeries. REVIEW METHODS: A literature search was conducted in PubMed, Scopus, CINAHL and Central for randomised controlled trials using dexmedetomidine for controlled hypotension in adult patients undergoing endoscopic sinus surgery or other nasal surgery. Meta-analysis of mean differences and single means were performed. RESULTS: Of 935 identified studies, 31 met the inclusion criteria. A statistically significant difference in Fromme-Boezaart surgical field visibility scores was found comparing dexmedetomidine to placebo (p < 0.00001) and propofol (p < 0.0001), but not other agents. A significant difference in intraoperative blood loss volume was found compared with placebo (51.5mL, p < 0.00001) and propofol (13.6mL, p < 0.0001), but not other agents. CONCLUSION: Dexmedetomidine demonstrated significantly improved surgical field visibility and blood loss volume compared with placebo and propofol, but not other agents. Dexmedetomidine is viable and useful for controlled hypotension in nasal surgery. Choice of controlled hypotension agent should follow patient and procedure-specific considerations.

PeriOperative Quality Initiative (POQI) international consensus statement on perioperative arterial pressure management.

Arterial pressure monitoring and management are mainstays of haemodynamic therapy in patients having surgery. This article presents updated consensus statements and recommendations on perioperative arterial pressure management developed during the 11th POQI PeriOperative Quality Initiative (POQI) consensus conference held in London, UK, on June 4-6, 2023, which included a diverse group of international experts. Based on a modified Delphi approach, we recommend keeping intraoperative mean arterial pressure ≥60 mm Hg in at-risk patients. We further recommend increasing mean arterial pressure targets when venous or compartment pressures are elevated and treating hypotension based on presumed underlying causes. When intraoperative hypertension is treated, we recommend doing so carefully to avoid hypotension. Clinicians should consider continuous intraoperative arterial pressure monitoring as it can help reduce the severity and duration of hypotension compared to intermittent arterial pressure monitoring. Postoperative hypotension is often unrecognised and might be more important than intraoperative hypotension because it is often prolonged and untreated. Future research should focus on identifying patient-specific and organ-specific hypotension harm thresholds and optimal treatment strategies for intraoperative hypotension including choice of vasopressors. Research is also needed to guide monitoring and management strategies for recognising, preventing, and treating postoperative hypotension.

Noradrenaline infusion prevents anesthesia-induced hypotension in severe aortic stenosis patients undergoing transcatheter aortic valve replacement: a retrospective observational study.

BACKGROUND: Patients with severe aortic valve stenosis (AS) are particularly prone to developing hypotension during general anesthesia induction, which increases postoperative morbidity and mortality. Although the preventive effect of a single vasopressor dose on anesthesia-induced hypotension has been reported, the effects of continuous vasopressor infusion are unknown. This study aimed to assess the effect of noradrenaline (NAd) infusion on hemodynamic stability during general anesthesia induction in severe AS patients undergoing transcatheter aortic valve replacement (TAVR). METHODS: This single-center, retrospective study included severe AS patients who underwent elective TAVR. Patients in the NAd group received a continuous prophylactic NAd infusion of 0.1 µg/kg/min from the time of anesthesia induction. The control group received inotropes and vasopressors as indicated by the occurrence of hypotension. The primary outcome was the lowest mean blood pressure (MBP) before the start of surgery. RESULTS: The study included 68 patients in the NAd group and 113 in the control group. The lowest MBP before the start of surgery was significantly higher in the NAd group than in the control group (63 ± 15 vs 47 ± 13 mmHg, P < 0.01). MBP immediately before intubation was also significantly higher in the NAd group (75 ± 17 vs 57 ± 16 mmHg, P < 0.01). Differences in postoperative complications between the groups were negligible. CONCLUSION: Continuous administration of NAd at 0.1 µg/kg/min in patients with severe AS might prevent hypotension during general anesthesia induction for TAVR.

Postoperative Hypotension After Cardiac Surgery Is Associated With Acute Kidney Injury.

OBJECTIVES: To describe the incidence of postoperative hypotension in patients undergoing cardiac surgery during the first 12 hours in the intensive care unit (ICU) and any relationship between hypotension and the development of acute kidney injury (AKI). DESIGN: This was a retrospective, observational cohort study. SETTING: The study took place in a single-center tertiary teaching hospital in London, UK. PARTICIPANTS: Adult patients (n = 100) who underwent elective cardiac surgery requiring intraoperative cardiopulmonary bypass between May and November 2021 were enrolled. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A hypotensive event was defined as mean arterial pressure <65 mmHg lasting at least 1 minute. Invasive blood pressure data was analyzed for the first 12 hours after surgery, and any association between postoperative hypotension and AKI was assessed. A total of 91% of patients experienced hypotension in the first 12 hours postprocedure. On average, patients experienced 9 hypotensive events, with events lasting an average of 5 minutes. A total of 16 patients (16%) developed at least stage 1 AKI. The average duration of hypotension was significantly higher in the AKI group (4.6 min [IQR 3.3, 8.0] v 8.1 min [IQR 5.2, 14.2], p = 0.029). Those suffering AKI had longer ICU and hospital stays. CONCLUSIONS: This study demonstrated that hypotension in the first 12 hours following cardiac surgery is common and prolonged hypotensive events are associated with developing AKI. This emphasizes the importance of treating hypotension aggressively and highlights a target for further research and intervention.

Syncope in the Emergency Department: A Practical Approach.

Syncope is a common condition encountered in the emergency department (ED), accounting for about 0.6-3% of all ED visits. Despite its high frequency, a widely accepted management strategy for patients with syncope in the ED is still missing. Since syncope can be the presenting condition of many diseases, both severe and benign, most research efforts have focused on strategies to obtain a definitive etiologic diagnosis. Nevertheless, in everyday clinical practice, a definitive diagnosis is rarely reached after the first evaluation. It is thus troublesome to aid clinicians' reasoning by simply focusing on differential diagnoses. With the current review, we would like to propose a management strategy that guides clinicians both in the identification of conditions that warrant immediate treatment and in the management of patients for whom a diagnosis is not immediately reached, differentiating those that can be safely discharged from those that should be admitted to the hospital or monitored before a final decision. We propose the mnemonic acronym RED-SOS: Recognize syncope; Exclude life-threatening conditions; Diagnose; Stratify the risk of adverse events; Observe; decide on the Setting of care. Based on this acronym, in the different sections of the review, we discuss all the elements that clinicians should consider when assessing patients with syncope.

The impact of pre-rehydration guided by carotid corrected flow time on hypotension prevention following general anesthesia induction in patients undergoing gastrointestinal surgery: a prospective randomized controlled trial.

Background: Patients undergoing gastrointestinal surgery often experience hypotension following general anesthesia induction due to insufficient volume. This study aimed to assess whether pre-rehydration guided by carotid corrected flow time (FTc) could mitigate post-induction hypotension induced by general anesthesia. Methods: Patients undergoing resection of gastrointestinal tumors were assigned to either the conventional treatment group (Group C) or the fluid treatment group based on FTc (Group F). Within Group F, patients were further divided into Group A (carotid FTc <340.7 ms) and Group B (carotid FTc ≥340.7 ms) based on pre-rehydration carotid FTc values. Group A patients received pre-rehydration with 250 mL of colloids (hydroxyethyl starch-HES) administered within 15 min until carotid FTc reached ≥340.7 ms to counteract hypovolemia prior to induction. Patients in Group B and Group C received a continuous HES infusion at a rate of 6 mL/kg/h 30 min before induction to compensate for physiological fluid loss. All patients received a perioperative background infusion of 3 mL/kg/h compound sodium chloride, with infusion rates optimized based on mean arterial pressure (MAP) and heart rate (HR). The incidence of post-induction hypotension was compared between Group C and Group F, as well as between Group A and Group B. Results: The incidence of hypotension after induction was significantly lower in Group F compared to Group C (26.4% vs. 46.7%, respectively; p < 0.001). Patients in Group A received significantly more pre-rehydration, leading to a greater increase in carotid FTc values compared to Group B (336.5 ± 64.5 vs. 174.3 ± 34.1 ms, p = 0.002). However, no significant difference in carotid FTc values after pre-rehydration was observed between the groups. There was no significant difference in the incidence of hypotension after general anesthesia induction between Group A and Group B (22.9% vs. 28.8%, p = 0.535). Conclusion: Pre-rehydration based on FTc can effectively reduce the occurrence of post-induction hypotension in patients undergoing gastrointestinal surgery who present with insufficient volume. Clinical trial registration: https://www.chictr.org.cn/showprojEN.html?proj=201481.

Corrigendum: Progression of functional and structural glaucomatous damage in relation to diurnal and nocturnal dips in mean arterial pressure.

[This corrects the article DOI: 10.3389/fcvm.2022.1024044.].

Determinants of orthostatic hypotension in type 2 diabetes: is cardiac autonomic neuropathy the main factor?

OBJECTIVES: To evaluate the determinants of orthostatic hypotension (OH) in type 2 diabetes (T2D) and the usefulness of ΔHR/ΔSBP, index of cardiac baroreflex function, in identifying neurogenic OH. METHODS: In 208 participants with T2D, we performed three heart rate based cardiovascular reflex tests (HR-CARTs) and OH test and assessed clinical history and variables. We defined OH as a systolic blood pressure (BP) fall ≥20 and ≥30 mmHg with supine BP <140 and ≥140 mmHg, respectively, and early and confirmed CAN based on 1 and 2 abnormal HR-CARTs. In participants with OH, we measured ΔHR/ΔSBP, using data from the lying to standing and OH test, and its diagnostic accuracy for neurogenic OH (as OH plus confirmed HR-CAN). RESULTS: OH was present in 25 participants and associated with lower HR-CARTs (P=0.01), higher HbA1c (P=0.0048), presence of CAN (P=0.0058), retinopathy (P=0.037), and peripheral vascular disease (P=0.0056), absence of hypertension (P=0.0008) and physical activity (P=0.0214), but not with interfering drugs and beta-blockers. In a multiple logistic regression, HR-CAN was the main independent determinant of OH (odds ratio: 4.74) with physical activity and hypertension (odds ratio: 0.16 and 0.23) (R2=0.22). ΔHR/ΔSBP had a good diagnostic accuracy for neurogenic OH (AUC: 0.816±0.087), and at the cut-off of 0.5 bpm/mmHg a sensitivity of 100% and specificity of 63.2%. CONCLUSION: CAN is still the main determinant of OH in T2D but does not explain all its variance with contribution of comorbidities and physical inactivity. The index ΔHR/ΔSBP might represent a useful clinical tool to identify neurogenic OH.

The effect of restrictive compared to liberal intravenous fluid volume on hypotension in adults undergoing major abdominal surgery.

In a cardiac output (CO) sub-study of the Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial, it was shown that restrictive fluid management was associated with lower cardiac index at the end of surgery. However, the association of the fluid protocol with intraoperative blood pressure was less clear. This paper primarily compares rates of hypotension between the two fluid regimens. The haemodynamic effects of these protocols may increase our understanding of perioperative fluid prescription. Using a data set of arterial pressure and cardiac output measurements, this observational cohort study primarily compares intraoperative hypotension rates defined by a mean arterial pressure < 65 mmHg between liberal and restrictive fluid protocols. Secondary analyses explore predictors of invasive mean arterial pressure and doppler-derived cardiac output, including fluid volume regimens and surgical duration. 105 patients had a combined total of 835 haemodynamic data capture events from the beginning to the end of the surgery. Here we report that a restrictive regimen is not associated with a greater proportion of participants who experience at least one episode of hypotension than the liberal regimen 64.1% vs. 61.5% (mean difference 2.6%, 95% CI - 15.9% to 21%, p = 0.78). Duration of surgery was associated with an increased risk of hypotension (OR 1.05, 1 to 1.1, p = 0.038). A fluid restriction protocol compared to liberal fluid administration is not associated with lower blood pressure.

Improvement of health-related quality of life after closure of spinal CSF leaks in patients with spontaneous intracranial hypotension.

OBJECTIVE: Spontaneous intracranial hypotension (SIH) is an important cause of orthostatic headaches caused by spinal CSF leaks. It has a strong negative impact on patients' socioeconomic status and health-related quality of life (HRQOL). This study aimed to analyze the impact of surgical and endovascular treatments on patients' HRQOL. METHODS: The authors conducted a prospective, observational cohort study that included all patients treated for SIH with microsurgery or embolization, depending on the type of CSF leak, at their institution between April 2022 and May 2023. Patients were asked to complete a specifically designed questionnaire, as well as the 15D HRQOL questionnaire, before and 3 months after treatment. RESULTS: A total of 21 patients (14 female; mean age 51.7 years) were treated in the study period. There were 12 (57%) type 1 leaks, 3 (14%) type 2, and 6 (29%) type 3. While 20 (95.2%) leaks were localized in the thoracic spine, only 1 (4.8%) was found in the lumbar spine. All patients completed the questionnaires. Fifteen (71.4%) patients underwent microsurgery and 6 (28.6%) endovascular embolization. The mean 15D score improved from 0.802 before to 0.889 after treatment (p = 0.013). Compared with an age- and sex-matched general population, HRQOL was significantly impaired in patients with SIH before treatment. After treatment, the authors found no significant difference in the overall HRQOL between patients and the healthy population. Mean headache intensity on a numeric rating scale improved from 8.1 before treatment to 2.3 after treatment (p = 0.003). Patients reported that SIH had a notable impact on their social and working life. CONCLUSIONS: SIH has a considerable negative impact on HRQOL. Microsurgery or embolization can dramatically improve HRQOL, subjective perception of health, and headache intensity. Therefore, surgical or endovascular treatment should be considered given the improvement observed in HRQOL for patients with SIH.

A Review of Fluid Bolus in Critically Ill Patients After Initial Volume Expansion: Bayesian Probability Analysis and Case Studies.

Introduction Fluid resuscitation is a crucial intervention for the management of critically ill patients. However, after initial volume expansion, the advantages of fluid bolus administration remain controversial. Our aim was to investigate the probabilistic reasoning against fluid bolus administration in critically ill patients after initial volume expansion. We then applied this reasoning to two hypothetical case studies that evaluated the benefits and risks associated with a fluid bolus for each patient. Methods We analyzed data from 12 previously published studies, totaling 334 patients, on fluid responsiveness in critically ill patients. Owing to differences in these studies, we used a Monte Carlo simulation based on their parameters to improve our Bayesian prior, generate strong estimates, and address uncertainty. Using the established Bayesian prior for volume responsiveness, we scrutinized two hypothetical case studies employing Bayesian mathematical notation to assess the pre-test probability, posterior probability, and likelihood ratios in patients with septic shock. Results The Monte Carlo simulation yielded a mean response rate of 0.54 (SD = 0.026), suggesting that only approximately 54% of patients were responsive to fluid bolus administration. These results had an effective sample size of 17,204 and an R-hat value of 1, demonstrating the reliability of our results. In our Bayesian case studies, we demonstrate the low probabilities of volume and VO2 responsiveness over time using common bedside testing. Conclusion Our analysis shows that the pretest and posttest probabilities for volume responsiveness following initial fluid resuscitation are low. Additional bedside testing should be pursued before administering additional volume. This approach emphasizes the importance of evidence-based decision-making in the management of critically ill patients to optimize patient outcomes and minimize potential risks.

Associations between intraoperative nociceptive response index and early postoperative acute kidney injury in patients undergoing non-cardiac surgery under general anesthesia: a single-center retrospective cohort study.

Both tissue hypoperfusion and elevated surgical stress during surgery are involved in the pathogenesis of postoperative acute kidney injury (AKI). Although intraoperative hypotension, which evokes renal hypoperfusion, has been reported to be associated with the development of postoperative AKI, there is no consensus on the association between surgical stress responses (e.g., hypertension and inflammation) and postoperative AKI. Given that intraoperative values of nociceptive response (NR) index are reportedly associated with surgical stress responses, the present study was performed to assess associations between intraoperative NR index and postoperative AKI in patients undergoing non-cardiac surgery. In this single-institutional retrospective cohort study, data of the highest and lowest values of NR index during surgery were obtained in consecutive adult patients undergoing non-cardiac surgery under general anesthesia from February 2022 to August 2023. Data on highest and lowest mean blood pressure (MBP) during surgery were also obtained. In 5,765 patients enrolled, multivariate regression analysis revealed that the development of early postoperative AKI was significantly associated with highest NR during surgery ≥ 0.920, lowest MBP during surgery < 54 mmHg, age ≥ 48 years, male sex, ASA-PS ≥ III, emergency, and duration of surgery ≥ 226 min. In addition to intraoperative hypotension, a higher level of intraoperative NR index is likely associated with higher incidence of early postoperative AKI in adult patients undergoing non-cardiac surgery under general anesthesia.