Optimal VAsopressor TitraTION in patients 65 years and older (OVATION-65): protocol and statistical analysis plan for a randomised clinical trial

Comparison of High-Normal Versus Low-Normal Mean Arterial Pressure at Target on Outcomes in Sepsis or Shock Patients: A Meta-Analysis of Randomized Control Trials

The objective of this meta-analysis was to compare the impact of a high-normal and a low-normal mean arterial pressure (MAP) target on outcomes in patients with sepsis or shock. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, two investigators conducted a thorough literature search across online databases, including PubMed, Cochrane Library, Web of Science, and EMBASE, spanning from inception to December 10, 2023. The assessed outcomes encompassed all-cause mortality, the need for renal replacement therapy, and the length of intensive care unit (ICU) stay. A total of four randomized controlled trials (RCTs) were included, involving 3507 participants with individual study participant counts ranging from 118 to 2463. The pooled analysis revealed no statistically significant difference in the risk of all-cause mortality between the two groups (Risk Ratio (RR): 0.94, 95% Confidence Interval (CI): 0.87 to 1.01). Furthermore, there was no disparity in the rates of renal replacement therapy and the duration of ICU stay between the high-normal and low-normal MAP groups. Our findings indicate no significant distinctions in mortality, rates of renal replacement therapy, or ICU stay duration between the two groups. However, future trials with larger sample sizes are warranted to comprehensively understand the nuanced effects of different MAP settings on outcomes in patients with sepsis and shock.

Lower Versus Higher Exposure to Vasopressor Therapy in Vasodilatory Hypotension: A Systematic Review With Meta-Analysis

OBJECTIVES

Balancing the risks of hypotension and vasopressor-associated adverse effects is a daily challenge in ICUs. We conducted a systematic review with meta-analysis to examine the effect of lower versus higher exposure to vasopressor therapy on mortality among adult ICU patients with vasodilatory hypotension.

DATA SOURCES

We searched Ovid Medline, Embase, and the Cochrane Central Register of Controlled Trials for studies published from inception to October 15, 2021.

STUDY SELECTION

We included randomized controlled trials of lower versus higher exposure to vasopressor therapy in adult ICU patients with vasodilatory hypotension without language or publication status limits.

DATA EXTRACTION

The primary outcome was 90-day all-cause mortality, with seven prespecified subgroups. Secondary outcomes included shorter- and longer-term mortality, use of life-sustaining therapies, vasopressor-related complications, neurologic outcome, and quality of life at longest reported follow-up. We conducted random-effects meta-analyses to calculate summary effect measures across individual studies (risk ratio [RR] for dichotomous variables, mean difference for continuous variables, both with 95% CIs). The certainty of the evidence was assessed using Grading of Recommendations, Assessment, Development, and Evaluation. We registered this review on the International Prospective Register of Systematic Reviews (CRD42021224434).

DATA SYNTHESIS

Of 3,403 records retrieved, 68 full-text articles were reviewed and three eligible studies included. Lower exposure to vasopressors probably lowers 90-day mortality but this is based on moderate-certainty evidence, lowered for imprecision (RR, 0.94; 95% CI, 0.87-1.02). There was no credible subgroup effect. Lower vasopressor exposure may also decrease the risk of supraventricular arrhythmia (odds ratio, 0.55; 95% CI, 0.36-0.86; low certainty).

CONCLUSIONS

In patients with vasodilatory hypotension who are started on vasopressors, moderate-certainty evidence from three randomized trials showed that lower vasopressor exposure probably lowers mortality. However, additional trial data are needed to reach an optimal information size to detect a clinically important 10% relative reduction in mortality with this approach.

The evolution of mean arterial pressure in critically ill patients on vasopressors before and during a trial comparing a specific mean arterial pressure target to usual care

Background

In randomized clinical controlled trials, the choice of usual care as the comparator may be associated with better clinician uptake of the study protocol and lead to more generalizable results. However, if care processes evolve to resemble the intervention during the course of a trial, differences between the intervention group and usual care control group may narrow. We evaluated the effect on mean arterial pressure of an unblinded trial comparing a lower mean arterial pressure target to reduce vasopressor exposure, vs. a clinician-selected mean arterial pressure target, in critically ill patients at least 65 years old.

Methods

For this multicenter observational study using data collected both prospectively and retrospectively, patients were recruited from five of the seven trial sites. We compared the mean arterial pressure of patients receiving vasopressors, who met or would have met trial eligibility criteria, from two periods: [1] at least 1 month before the trial started, and [2] during the trial period and randomized to usual care, or not enrolled in the trial.

Results

We included 200 patients treated before and 229 after trial initiation. There were no differences in age (mean 74.5 vs. 75.2 years; p = 0.28), baseline Acute Physiology and Chronic Health Evaluation II score (median 26 vs. 26; p = 0.47) or history of chronic hypertension (n = 126 [63.0%] vs. n = 153 [66.8%]; p = 0.41). Mean of the mean arterial pressure was similar between the two periods (72.5 vs. 72.4 mmHg; p = 0.76).

Conclusions

The initiation of a trial of a prescribed lower mean arterial pressure target, compared to a usual clinician-selected target, was not associated with a change in mean arterial pressure, reflecting stability in the net effect of usual clinician practices over time. Comparing prior and concurrent control groups may alleviate concerns regarding drift in usual practices over the course of a trial or permit quantification of any change.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01529-w.