Hypotensive Events Research Articles

Development and Validation of a Prediction Model for Acute Hypotensive Events in Intensive Care Unit Patients.

Background: Persistent hypotension in the intensive care unit (ICU) is associated with increased mortality. Predicting acute hypotensive events can lead to timely intervention. We aimed to develop a prediction model of acute hypotensive events in patients admitted to the ICU. Methods: We included adult patients admitted to the Nagoya City University (NCU) Hospital ICU between January 2018 and December 2021 for model training and internal validation. The MIMIC-III database was used for external validation. A hypotensive event was defined as a mean arterial pressure < 60 mmHg for at least 5 min in 10 min. The input features were age, sex, and time-series data for vital signs. We compared the area under the receiver-operating characteristic curve (AUROC) of three machine-learning algorithms: logistic regression, the light gradient boosting machine (LightGBM), and long short-term memory (LSTM). Results: Acute hypotensive events were found in 1325/1777 (74.6%) and 2691/5266 (51.1%) of admissions in the NCU and MIMIC-III cohorts, respectively. In the internal validation, the LightGBM model had the highest AUROC (0.835), followed by the LSTM (AUROC 0.834) and logistic regression (AUROC 0.821) models. Applying only blood pressure-related features, the LSTM model achieved the highest AUROC (0.843) and consistently showed similar results in external and internal validation. Conclusions: The LSTM model using only blood pressure-related features had the highest AUROC with comparable performance in external validation.

Postoperative Hypotension After Cardiac Surgery Is Associated With Acute Kidney Injury

ObjectivesTo describe the incidence of post-operative hypotension in patients undergoing cardiac surgery during the first 12 hours in ICU and any relationship between hypotension and the development of acute kidney injury (AKI). DesignRetrospective, observational cohort study. SettingSingle centre tertiary teaching hospital in London, UK. Participants100 adult patients who underwent elective cardiac surgery requiring intra-operative cardiopulmonary bypass between May 2021 and November 2021. InterventionsNone. Measurements and Main ResultsA hypotensive event was defined as mean arterial pressure < 65 mmHg of at least 1 minute in duration. Invasive blood pressure data was analysed for the first 12 hours after the surgery and any association between post-operative hypotension and AKI was assessed. 91% of patients experienced hypotension in the first 12 hours post-procedure. On average, a patient would experience 9 hypotensive events, with an event lasting for an average of 5 minutes. 16 patients (16%) developed at least stage 1 AKI. The average duration of hypotension was significantly higher in the AKI group (4.6 min [3.3, 8.0] vs 8.1 min [5.2, 14.2], p=0.029). Those suffering an AKI had a longer ICU and hospital length of stay. ConclusionsThis study has demonstrated that hypotension in the first 12 hours after cardiac surgery is common and that prolonged hypotensive events are associated with developing an acute kidney injury. This emphasises the importance of treating hypotension aggressively and highlights a target for further research and intervention.

Remimazolam to prevent hemodynamic instability during catheter ablation under general anesthesia: a randomized controlled trial.

Maintaining hemodynamic stability during cardiac ablation under general anesthesia is challenging. Remimazolam, a novel ultrashort-acting benzodiazepine, is characterized by maintaining comparatively stable blood pressure and does not influence the cardiac conduction system, which renders it a reasonable choice for general anesthesia for cardiac ablation. We aimed to evaluate whether remimazolam is associated with a decreased incidence of intraoperative hypotension compared with desflurane. In this single-centre, parallel-group, prospective, single-blind, randomized clinical trial, we randomized patients (1:1) into a remimazolam group (remimazolam-based total intravenous anesthesia) or desflurane group (propofol-induced and desflurane-maintained inhalational anesthesia) during cardiac ablation procedures for arrhythmia. The primary outcome was the incidence of intraoperative hypotensive events, defined as mean arterial pressure of < 60mm Hg at any period. Overall, we enrolled 96 patients between 2 August 2022 and 19 May 2023 (47 and 49 patients in the remimazolam and desflurane groups, respectively). The remimazolam group showed a significantly lower incidence of hypotensive events (14/47, 30%) than the desflurane group (29/49, 59%; relative risk [RR], 0.5; 95% confidence interval [CI], 0.31 to 0.83; P = 0.004). Remimazolam was associated with a lower requirement for bolus or continuous vasopressor infusion than desflurane was (23/47, 49% vs 43/49, 88%; RR, 0.56; 95% CI, 0.41 to 0.76; P < 0.001). No between-group differences existed in the incidence of perioperative complications such as nausea, vomiting, oxygen desaturation, delayed emergence, or pain. Remimazolam was a viable option for general anesthesia for cardiac ablation. Remimazolam-based total intravenous anesthesia was associated with significantly fewer hypotensive events and vasopressor requirements than desflurane-based inhalational anesthesia was, without significantly more complications. ClinicalTrials.gov (NCT05486377); first submitted 1 August 2022.

Haemodynamic effects of intravenous acetaminophen in critically ill paediatric patients: a retrospective chart review

ObjectivesHaemodynamic changes following intravenous acetaminophen are well studied in adults. Limited data are published in critically ill paediatric patients, especially from the Middle East. We aim to investigate haemodynamic effects...

Efficacy and safety during endoscopic retrograde cholangiopancreatography (ERCP) under total intravenous anesthesia – propofol alone versus propofol supplemented with dexketa, a comparative study in medical college, Kolkata

Background: Endoscopic retrograde cholangiopancreatography (ERCP) is an invasive procedure and, hence, is distressing for awake patients, requiring an adequate level of anesthesia. Recent advancements have encouraged the use of monitored anesthesia care, that allows the patient to tolerate unpleasant experiences during procedures while maintaining cardio-respiratory function. Usually, propofol-based anesthesia is given in ERCP. The main aim of this study is to compare the effect of propofol alone and propofol with ketamine and dexmedetomidine on the hemodynamics during ERCP, recovery profile, and side effects (if any). Aims and Objectives: (1) To compare efficacy in terms of hemodynamic stability and desaturation events. (2) Recovery and quality of recovery. (3) Pain score. (4) Incidence of post-operative nausea and vomiting. Materials and Methods: This is a comparative double-blinded study. Adult patients from the age group of 18–70 years belonging to the American Society of Anesthesiologists (ASA-I) and ASA-II who had undergone ERCP under total intravenous anesthesia were taken and randomly assigned to either of the two groups. Both groups received 0.01 mg/kg glycopyrrolate, 0.1 mg/kg ondansetron, 0.05 mg/kg midazolam, 50 mcg fentanyl, and 40 mg hyoscine. Group A patients received 30 mg propofol as a bolus dose and then repeated according to requirements. Group B patients received 0.5 mcg/kg dexmedetomidine as a loading dose and 0.3 mcg/kg/h as a maintenance infusion dose. 30 mg propofol was given before negotiating scope and then 1 mL (1:1) mixture of propofol and ketamine was repeated according to requirements. Total propofol consumption, hemodynamics, quality of recovery, and side effects (if any) were recorded at regular intervals. Results: The study showed significant cases in Group A had episodes of hypotension and apneic events, whereas there were very few hemodynamic instability and almost no apneic events in Group B patients. The requirement of propofol was much higher in Group A patients. Conclusion: Dexmedetomidine when used along with propofol and ketamine in ERCP patients reduced the dose requirement of propofol and maintained hemodynamic stability without causing any apneic events.

Comparison of Differences in Cohort (Forward) and Case Control (Backward) Methodologic Approaches for Validation of the Hypotension Prediction Index.

The Hypotension Prediction Index (the index) software is a machine learning algorithm that detects physiologic changes that may lead to hypotension. The original validation used a case control (backward) analysis that has been suggested to be biased. This study therefore conducted a cohort (forward) analysis and compared this to the original validation technique. A retrospective analysis of data from previously reported studies was conducted. All data were analyzed identically with two different methodologies, and receiver operating characteristic curves were constructed. Both backward and forward analyses were performed to examine differences in area under the receiver operating characteristic curves for the Hypotension Prediction Index and other hemodynamic variables to predict a mean arterial pressure (MAP) less than 65 mmHg for at least 1 min 5, 10, and 15 min in advance. The analysis included 2,022 patients, yielding 4,152,124 measurements taken at 20-s intervals. The area under the curve for the index predicting hypotension analyzed by backward and forward methodologies respectively was 0.957 (95% CI, 0.947 to 0.964) versus 0.923 (95% CI, 0.912 to 0.933) 5 min in advance, 0.933 (95% CI, 0.924 to 0.942) versus 0.923 (95% CI, 0.911 to 0.933) 10 min in advance, and 0.929 (95% CI, 0.918 to 0.938) versus 0.926 (95% CI, 0.914 to 0.937) 15 min in advance. No variable other than MAP had an area under the curve greater than 0.7. The areas under the curve using forward analysis for MAP predicting hypotension 5, 10, and 15 min in advance were 0.932 (95% CI, 0.920 to 0.940), 0.929 (95% CI, 0.918 to 0.938), and 0.932 (95% CI, 0.921 to 0.940), respectively. The R2 for the variation in the index due to MAP was 0.77. Using an updated methodology, the study found that the utility of the Hypotension Prediction Index to predict future hypotensive events is high, with an area under the receiver operating characteristics curve similar to that of the original validation method.

Impact of Gabapentin on Postoperative Hypotension in Enhanced Recovery after Surgery Protocols for Microvascular Breast Reconstruction.

Enhanced recovery after surgery (ERAS) protocols have been associated with hypotensive episodes after autologous breast reconstruction. Gabapentin (Gaba), a nonopioid analgesic used in ERAS, has been shown to attenuate postoperative hemodynamic responses. This study assesses ERAS's impact, with and without Gaba, on postoperative hypotension after microvascular breast reconstruction. Three cohorts were studied: traditional pathway, ERAS + Gaba, and ERAS no-Gaba. We evaluated length of stay, inpatient narcotic use [morphine milligram equivalents (MME)], mean systolic blood pressure, hypotension incidence, and complications. The traditional cohort was retrospectively reviewed, whereas the ERAS groups were enrolled prospectively after the initiation of the protocol in April 2019 (inclusive of Gaba until October 2022). In total, 441 patients were analyzed. The three cohorts, in the order mentioned above, were similar in age and bilateral reconstruction rates (57% versus 61% versus 60%). The ERAS cohorts, both with and without Gaba, had shorter stays (P < 0.01). Inpatient MME was significantly less in the ERAS + Gaba cohort than the traditional or ERAS no-Gaba cohorts (medians: 112 versus 178 versus 158 MME, P < 0.01). ERAS + Gaba significantly increased postoperative hypotensive events on postoperative day (POD) 1 and 2, with notable reduction after Gaba removal (P < 0.05). Across PODs 0-2, mean systolic blood pressure was highest in the traditional cohort, followed by ERAS no-Gaba, then the ERAS + Gaba cohort (P < 0.05). Complication rates were similar across all cohorts. Postmicrovascular breast reconstruction, ERAS + Gaba reduced overall inpatient narcotic usage, but increased hypotension incidence. Gaba removal from the ERAS protocol reduced postoperative hypotension incidence while maintaining similar stay lengths and complication rates.

Comparative Effectiveness and Safety of Intermittent, Repeated, or Continuous Use of Levosimendan, Milrinone, or Dobutamine in Patients With Advanced Heart Failure: A Network and Single-Arm Meta-analysis.

The aim of this study was to synthesize the available evidence regarding differences in the long-term safety and efficacy of intermittent, repeated, or continuous palliative inotropic therapy among patients with advanced heart failure. We systematically searched the PubMed, Embase, and Cochrane Library electronic databases, with a cutoff date of November 23, 2023, for studies reporting outcomes in adult patients with advanced heart failure treated with intermittent, repeated, or continuous levosimendan, milrinone, or dobutamine. Forty-one studies (18 randomized controlled trials and 23 cohort studies) comprising 5137 patients met the inclusion criteria. The results of the network meta-analysis of randomized controlled trials showed that levosimendan had significant advantages over milrinone or dobutamine in reducing mortality and improving left ventricular ejection fraction. A single-arm meta-analysis also indicated that levosimendan had the lowest mortality and significantly improved B-type brain natriuretic peptide and left ventricular ejection fraction. Regarding safety, hypotension events were observed more frequently in the levosimendan and milrinone groups. However, the current evidence is limited by the heterogeneity and relatively small sample size of the studies.

A Quantitative Assessment of Cerebral Hemodynamic Perturbations Associated with Long R-R Intervals in Atrial Fibrillation: A Pilot-Case-Based Experience.

Background and Objectives: Atrial fibrillation (AF) results in systemic hemodynamic perturbations which impact cerebral circulation, possibly contributing to the development of dementia. However, evidence documenting effects in cerebral perfusion is scarce. The aim of this study is to provide a quantitative characterization of the magnitude and time course of the cerebral hemodynamic response to the short hypotensive events associated with long R-R intervals, as detected by near-infrared spectroscopy (NIRS). Materials and Methods: Cerebral NIRS signals and arterial blood pressure were continuously recorded along with an electrocardiogram in twelve patients with AF undergoing elective electrical cardioversion (ECV). The top 0.5-2.5% longest R-R intervals during AF were identified in each patient and used as triggers to carry out the triggered averaging of hemodynamic signals. The average curves were then characterized in terms of the latency, magnitude, and duration of the observed effects, and the possible occurrence of an overshoot was also investigated. Results: The triggered averages revealed that long R-R intervals produced a significant drop in diastolic blood pressure (-13.7 ± 6.1 mmHg) associated with an immediate drop in cerebral blood volume (THI: -0.92 ± 0.46%, lasting 1.9 ± 0.8 s), followed by a longer-lasting decrease in cerebral oxygenation (TOI: -0.79 ± 0.37%, lasting 5.2 ± 0.9 s, p < 0.01). The recovery of the TOI was generally followed by an overshoot (+1.06 ± 0.12%). These effects were progressively attenuated in response to R-R intervals of a shorter duration. Conclusions: Long R-R intervals cause a detectable and consistent cerebral hemodynamic response which concerns both cerebral blood volume and oxygenation and outlasts the duration of the systemic perturbation. These effects are compatible with the activation of dynamic autoregulatory mechanisms in response to the hypotensive stimulus.

AcumenTM hypotension prediction index guidance for prevention and treatment of hypotension in noncardiac surgery: a prospective, single-arm, multicenter trial

BackgroundIntraoperative hypotension is common during noncardiac surgery and is associated with postoperative myocardial infarction, acute kidney injury, stroke, and severe infection. The Hypotension Prediction Index software is an algorithm based on arterial waveform analysis that alerts clinicians of the patient’s likelihood of experiencing a future hypotensive event, defined as mean arterial pressure < 65 mmHg for at least 1 min.MethodsTwo analyses included (1) a prospective, single-arm trial, with continuous blood pressure measurements from study monitors, compared to a historical comparison cohort. (2) A post hoc analysis of a subset of trial participants versus a propensity score-weighted contemporaneous comparison group, using external data from the Multicenter Perioperative Outcomes Group (MPOG). The trial included 485 subjects in 11 sites; 406 were in the final effectiveness analysis. The post hoc analysis included 457 trial participants and 15,796 comparison patients. Patients were eligible if aged 18 years or older, American Society of Anesthesiologists (ASA) physical status 3 or 4, and scheduled for moderate- to high-risk noncardiac surgery expected to last at least 3 h. Measurements: minutes of mean arterial pressure (MAP) below 65 mmHg and area under MAP < 65 mmHg.ResultsAnalysis 1: Trial subjects (n = 406) experienced a mean of 9 ± 13 min of MAP below 65 mmHg, compared with the MPOG historical control mean of 25 ± 41 min, a 65% reduction (p < 0.001). Subjects with at least one episode of hypotension (n = 293) had a mean of 12 ± 14 min of MAP below 65 mmHg compared with the MPOG historical control mean of 28 ± 43 min, a 58% reduction (p< 0.001). Analysis 2: In the post hoc inverse probability treatment weighting model, patients in the trial demonstrated a 35% reduction in minutes of hypotension compared to a contemporaneous comparison group [exponentiated coefficient: − 0.35 (95%CI − 0.43, − 0.27); p < 0.001].ConclusionsThe use of prediction software for blood pressure management was associated with a clinically meaningful reduction in the duration of intraoperative hypotension. Further studies must investigate whether predictive algorithms to prevent hypotension can reduce adverse outcomes.Trial registrationClinical trial number: NCT03805217. Registry URL: https://clinicaltrials.gov/ct2/show/NCT03805217. Principal investigator: Xiaodong Bao, MD, PhD. Date of registration: January 15, 2019.

Effects of opioid-free anaesthesia compared with balanced general anaesthesia on nausea and vomiting after video-assisted thoracoscopic surgery: a single-centre randomised controlled trial

ObjectivesOpioid-free anaesthesia (OFA) has emerged as a promising approach for mitigating the adverse effects associated with opioids. The objective of this study was to evaluate the impact of OFA on...

Prevention of post-operative delirium using an overnight infusion of dexmedetomidine in patients undergoing cardiac surgery: a pragmatic, randomized, double-blind, placebo-controlled trial

BackgroundAfter cardiac surgery, post-operative delirium (PoD) is acknowledged to have a significant negative impact on patient outcome. To date, there is no valuable and specific treatment for PoD. Critically ill patients often suffer from poor sleep condition. There is an association between delirium and sleep quality after cardiac surgery. This study aimed to establish whether promoting sleep using an overnight infusion of dexmedetomidine reduces the incidence of delirium after cardiac surgery.MethodsRandomized, pragmatic, multicentre, double-blind, placebo controlled trial from January 2019 to July 2021. All adult patients aged 65 years or older requiring elective cardiac surgery were randomly assigned 1:1 either to the dexmedetomidine group or the placebo group on the day of surgery. Dexmedetomidine or matched placebo infusion was started the night after surgery from 8 pm to 8 am and administered every night while the patient remained in ICU, or for a maximum of 7 days. Primary outcome was the occurrence of postoperative delirium (PoD) within the 7 days after surgery.ResultsA total of 348 patients provided informed consent, of whom 333 were randomized: 331 patients underwent surgery and were analysed (165 assigned to dexmedetomidine and 166 assigned to placebo). The incidence of PoD was not significantly different between the two groups (12.6% vs. 12.4%, p = 0.97). Patients treated with dexmedetomidine had significantly more hypotensive events (7.3% vs 0.6%; p < 0.01). At 3 months, functional outcomes (Short-form 36, Cognitive failure questionnaire, PCL-5) were comparable between the two groups.ConclusionIn patients recovering from an elective cardiac surgery, an overnight infusion of dexmedetomidine did not decrease postoperative delirium.Trial registration This trial was registered on ClinicalTrials.gov (number: NCT03477344; date: 26th March 2018).

Intensive vs Conventional Blood Pressure Control After Thrombectomy in Acute Ischemic Stroke

Endovascular thrombectomy (EVT) is standard treatment for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO), but optimal post-EVT blood pressure (BP) control remains debated. To assess the association of different systolic BP targets following EVT with functional outcomes, mortality, and complications in patients with AIS due to LVO. Systematic review and meta-analysis of databases (PubMed, Embase, Web of Science, Scopus, and Cochrane Library) to September 8, 2023. Inclusion criteria consisted of randomized clinical trials examining post-EVT management of systolic BP in patients with AIS and LVO comparing intensive vs conventional targets. Nonrandomized studies, observational studies, noninterventional trials, meeting abstracts, duplicate studies, studies with overlapping data, and non-English language studies were excluded. Two authors independently applied these criteria through a blinded review, with discrepancies resolved through consensus. The risk of bias in the included studies was assessed using the revised tool for assessing risk of bias in randomized trials. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline. Three authors extracted data regarding study characteristics, baseline patient data, and outcomes of interest. The pooled data were analyzed using a random-effects meta-analysis. Rates of functional independence, 90-day mortality, symptomatic intracranial hemorrhage, and hypotensive events. A total of 4 randomized clinical trials with 1571 initially enrolled patients were included in the analysis. Lower functional independence rates were observed in the intensive control group (relative risk [RR], 0.81 [95% CI, 0.67-0.98]). No significant differences were found in 90-day mortality (RR, 1.18 [95% CI, 0.92-1.52]), symptomatic intracranial hemorrhage (RR, 1.12 [95% CI, 0.75-1.67]), or hypotensive events (RR, 1.80 [95% CI, 0.37-8.76]). There was minimal heterogeneity among the studies included in the functional independence outcome (I2 = 13% and τ2 = 0.003), which was absent among other outcomes (I2 = 0 and τ2 = 0). These findings suggest that intensive post-EVT BP reduction does not yield benefits and may carry risks. While awaiting the results of additional ongoing trials, a conservative BP management strategy after endovascular recanalization is favored in daily practice.

Effectiveness and safety of empegfilgrastim (Extimia®, BIOCAD) in patients with lymphoproliferative diseases receiving cytotoxic therapy: results of LEGERITY, a multicenter retrospective-and-prospective observational post-marketing study

Aim. To evaluate the effectiveness and safety of Extimia® BIOCAD (international non-proprietary name: empegfilgrastim) to reduce the incidence and duration of neutropenia, the incidence of febrile neutropenia (FN) and infections associated with FN in patients with lymphoproliferative diseases receiving myelosuppressive therapy.&#x0D; Materials and methods. The paper presents the results of a multicenter retrospective-and-prospective observational post-marketing study of the safety and effectiveness of Extimia® BIOCAD (international non-proprietary name: empegfilgrastim) in patients with lymphoproliferative diseases receiving cytotoxic therapy. Initially, the study was defined as retrospective-and-prospective. However, only 2 of 671 (0.3%) patients were included retrospectively. Thus, the study is based on the evaluation of prospectively collected data. The analysis describes the characteristics and treatment of 671 patients diagnosed with lymphoma who received one or more cycles of chemotherapy in the LEGERITY study. The endpoints of interest included the incidence of grade 3–4 neutropenia, FN, and grade 3–4 infectious complications, the frequency of antibiotic therapy, and the incidence of all adverse reactions in patients who received at least one dose of the study medication.&#x0D; Results. A total of 671 patients were enrolled in the study, the majority having B-cell non-Hodgkin lymphoma (428/671, 64%) and Hodgkin lymphoma (211/671, 31%). The mean age was 54 years (18–84); 35% (236/671) of patients were elderly (over 60). The number of injections of empegfilgrastim for the entire observation period was 3093 (n=671). Adverse events were reported in 57/3093 (1.8%) cases. The most common adverse events were mild to moderate ossalgia and myalgia (27/671, 4%), back pain, and arthralgia (12/671, 1.8%), which did not require drug therapy. Two patients developed serious adverse reactions – CTCAE v.5 grade 4 hypotension events. 529 (78.8%) patients received at least 4 courses of chemotherapy. FN was reported in 14 (2.6%) patients and did not require antimicrobial therapy.&#x0D; Conclusion. The final analysis results confirm the high clinical efficacy and safety of the Russian original pegylated granulocyte colony-stimulating factor empegfilgrastim (Extimia®) in patients with indolent and aggressive lymphomas. The data obtained from real-world clinical practice demonstrate a favorable safety and tolerability profile of empegfilgrastim in all age groups, including the elderly population.

Safety of Intravenous Push Valproate Compared with Intravenous Piggyback at a Tertiary Academic Medical Center.

Data are limited regarding the safety associated with administering valproate sodium by intravenous push (IVP) compared with intravenous piggyback (IVPB). The objective of this retrospective pre-post analysis was to compare the safety profile of valproate administration via IVPB from March to May 2022 and IVP from June to August 2022. A total of 890 IVPB and 440 IVP administrations were included. The major endpoint of this analysis was the incidence of infusion site reactions (infiltration or phlebitis). The incidence of documented intravenous (IV) site reactions demonstrated minimal differences between both IVPB and IVP administration cohorts. Based on the Naranjo algorithm, all IVPB and IVP infusion site reactions were classified as possible or doubtful. Additional safety endpoints included bradycardia, hypotension, or sedation attributable to valproate sodium administration. Similar safety profiles were observed, including valproate-associated bradycardia, hypotension, and sedation events. All safety events were further classified as possible or doubtful by the Naranjo algorithm. Time from pharmacist verification to valproate administration was also collected. The mean time from pharmacist order verification to valproate administration was significantly faster in the IVP cohort compared to the IVPB cohort. IVP valproate administration may be considered safe, allowing for more optimal clinical and operational outcomes in the acute care setting.

Continuous vs intermittent Non-Invasive blood pressure MONitoring in preventing postoperative organ failure (niMON): study protocol for an open-label, multicenter randomized trial

BackgroundBlood pressure has become one of the most important vital signs to monitor in the perioperative setting. Recently, the Italian Society of Anesthesia Analgesia Resuscitation and Intensive Care (SIAARTI) recommended, with low level of evidence, continuous monitoring of blood pressure during the intraoperative period. Continuous monitoring allows for early detection of hypotension, which may potentially lead to a timely treatment. Whether the ability to detect more hypotension events by continuous noninvasive blood pressure (C-NiBP) monitoring can improve patient outcomes is still unclear. Here, we report the rationale, study design, and statistical analysis plan of the niMON trial, which aims to evaluate the effect of intraoperative C-NiBP compared with intermittent (I-NiBP) monitoring on postoperative myocardial and renal injury.MethodsThe niMon trial is an investigator-initiated, multicenter, international, open-label, parallel-group, randomized clinical trial. Eligible patients will be randomized in a 1:1 ratio to receive C-NiBP or I-NiBP as an intraoperative monitoring strategy. The proportion of patients who develop myocardial injury in the first postoperative week is the primary outcome; the secondary outcomes are the proportions of patients who develop postoperative AKI, in-hospital mortality rate, and 30 and 90 postoperative days events. A sample size of 1265 patients will provide a power of 80% to detect a 4% absolute reduction in the rate of the primary outcome.ConclusionsThe niMON data will provide evidence to guide the choice of the most appropriate intraoperative blood pressure monitoring strategy.Clinical trial registrationClinical Trial Registration: NCT05496322, registered on the 5th of August 2023.

The Incidence of Perioperative Hypotension in Patients Undergoing Major Abdominal Surgery with the Use of Arterial Waveform Analysis and the Hypotension Prediction Index Hemodynamic Monitoring-A Retrospective Analysis.

Intraoperative hypotension (IH) is common in patients receiving general anesthesia and can lead to serious complications such as kidney failure, myocardial injury and increased mortality. The Hypotension Prediction Index (HPI) algorithm is a machine learning system that analyzes the arterial pressure waveform and alerts the clinician of an impending hypotension event. The purpose of the study was to compare the frequency of perioperative hypotension in patients undergoing major abdominal surgery with different types of hemodynamic monitoring. The study included 61 patients who were monitored with the arterial pressure-based cardiac output (APCO) technology (FloTrac group) and 62 patients with the Hypotension Prediction Index algorithm (HPI group). Our primary outcome was the time-weighted average (TWA) of hypotension below < 65 mmHg. The median TWA of hypotension in the FloTrac group was 0.31 mmHg versus 0.09 mmHg in the HPI group (p = 0.000009). In the FloTrac group, the average time of hypotension was 27.9 min vs. 8.1 min in the HPI group (p = 0.000023). By applying the HPI algorithm in addition to an arterial waveform analysis alone, we were able to significantly decrease the frequency and duration of perioperative hypotension events in patients who underwent major abdominal surgery.

Intranasal dexmedetomidine as premedication for magnetic resonance imaging examinations in dogs with neurological disorders mitigates hypotension and hypothermia.

This study aimed to evaluate the safety and feasibility of intranasal administration of dexmedetomidine as a premedication for preventing hypotension and hypothermia in canine patients undergoing MRI examinations. Dogs undergoing MRI examinations for neurological disorders were enrolled in this study. The dogs were randomly assigned: 15 to the N-Dex group (without premedication) and 13 to the Dex group (125 μg/m2 of dexmedetomidine, intranasally, as a premedication). During the examination, pulse rate, systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure were recorded every 5 minutes for the first 30 minutes. Body temperature was measured before and after the examination. Any adverse events during the procedure were documented. Significant changes in pulse rate during the examination were not distinguishable. Although blood pressure and body temperature decreased in both groups under anesthesia, dogs in the Dex group had a significantly smaller drop in blood pressure and body temperature and fewer hypotension events than those in the N-Dex group MRI examinations of 1 hour's duration. Two dogs in the Dex group exhibited bradycardia at 45 and 60 minutes of MRI examination, which resolved after receiving atipamezole. Our results indicate that intranasal administration of 125 μg/m2 of dexmedetomidine as premedication is safe and can potentially mitigate hypothermia and hypotension in dogs with neurological disorders during MRI examinations.

Does intradialytic oral nutrition impact hemodialysis patients' quality of life, appetite, and safety? A pilot study of a crossover clinical trial.

Introduction: due to the catabolic characteristics of hemodialysis (HD), patients should consume foods or supplements during this treatment to meet their energy requirements and maintain a neutral nitrogen balance; however, there are some outcomes in which the effect of intradialytic oral nutrition (ION) is scarcely known. Objectives: this study aims to evaluate the effect of two types of ION (liquid and solid) on Quality of Life (QoL), appetite, and safety in HD patients. Methods: a pilot randomized, crossover clinical trial was performed in 18 patients on chronic HD. One group received ION for 18 HD sessions, after the crossover continued for 18 more sessions in the control group, and vice versa. We recorded QoL, appetite, systolic blood pressure (SBP), and intradialytic hypotension (IH) events. Results: clinical improvement was observed for most QoL components. Regardless of the consistency of supplementation, SBP increased to 4.10 mmHg. Both study groups reported a "very good-to-good" appetite. Conclusion: favorable clinical changes were observed in QoL scores during the study. Five of six IH events were reported for patients in the ION group, and SBP increased within the safe range (≤ 10 mmHg); appetite remained stable in both groups. Therefore, we concluded that this strategy, regardless of implementation consistency, is safe to be used in stable patients.

Frequency Domain Deep Learning With Non-Invasive Features for Intraoperative Hypotension Prediction.

Intraoperative hypotension can lead to postoperative organ dysfunction. Previous studies primarily used invasive arterial pressure as the key biosignal for the detection of hypotension. However, these studies had limitations in incorporating different biosignal modalities and utilizing the periodic nature of biosignals. To address these limitations, we utilized frequency-domain information, which provides key insights that time-domain analysis cannot provide, as revealed by recent advances in deep learning. With the frequency-domain information, we propose a deep-learning approach that integrates multiple biosignal modalities. We used the discrete Fourier transform technique, to extract frequency information from biosignal data, which we then combined with the original time-domain data as input for our deep learning model. To improve the interpretability of our results, we incorporated recent interpretable modules for deep-learning models into our analysis. We constructed 75 994 segments from the data of 3226 patients to predict hypotension during surgery. Our proposed frequency-domain deep-learning model outperformed conventional approaches that rely solely on time-domain information. Notably, our model achieved a greater increase in AUROC performance than the time-domain deep learning models when trained on non-invasive biosignal data only (AUROC 0.898 [95% CI: 0.885-0.91] vs. 0.853 [95% CI: 0.839-0.867]). Further analysis revealed that the 1.5-3.0 Hz frequency band played an important role in predicting hypotension events. Utilizing the frequency domain not only demonstrated high performance on invasive data but also showed significant performance improvement when applied to non-invasive data alone. Our proposed framework offers clinicians a novel perspective for predicting intraoperative hypotension.