Midodrine as an Adjuvant to Intravenous Vasopressor Agents in Adults With Resolving Shock: Systematic Review and Meta-Analysis

Evaluation of Midodrine Utilization in Patients with Cancer and Heart Failure

PURPOSE

The purpose of this study was to evaluate safety and cardiovascular outcomes as well as overall survival of cancer patients with concomitant heart failure (HF) treated with midodrine for hypotension.

METHODS

Adult patients diagnosed with cancer and HF who were treated with midodrine at a tertiary cancer center from 03/2013 to 08/2021 were identified. Demographic and clinical parameters were collected retrospectively.

RESULTS

A total of 85 patients were included with a median age of 68 years (IQR: 60, 74; 33% female and 85% White). Of those, 31% had HFpEF (EF ≥ 50%), 42% HF with mildly reduced EF (HFmrEF; EF 41-49%), and 27% HFrEF (EF ≤ 40%). The most common indication for midodrine use was orthostatic hypotension (49%). Midodrine was continued for at least one month in 57% of the patients. Supine hypertension was the only side effect reported in 6% of patients. No statistically significant changes in NYHA class, guideline-directed medical therapy, cardiac biomarkers (NT-proBNP or troponin T), echocardiographic findings or cardiovascular hospitalizations were observed between patients who continued treatment with midodrine compared to those who stopped using midodrine over a median follow-up of 38 months. In the multivariable cox regression analysis, continuation of midodrine, compared to discontinuation, and use of midodrine for orthostatic hypotension, as opposed to other causes of hypotension, were not associated with an increased risk of mortality (HR 0.41, 95% CI 0.24-0.69, p < .0001; HR 0.34, 95% CI 0.18-0.64, p < .001, respectively). In contrast, elevated creatinine (> 1.3 for males and > 1.1 for females) was associated with an increased risk of mortality (HR 1.83, 95% CI 1.07-3.14). LVEF was not significantly associated with lower or higher risk of mortality.

CONCLUSIONS

In our study, midodrine use in patients with cancer and HF was not associated with significant adverse effects, worse cardiovascular outcomes, or increased risk of mortality. Larger, prospective studies are needed to confirm these findings.

Adjunctive Midodrine Therapy for Vasopressor-Dependent Shock in the ICU: A Systematic Review and Meta-Analysis

OBJECTIVES

To summarize the efficacy of midodrine as an adjunctive therapy in critically ill patients. Safety of midodrine was assessed as a secondary outcome.

DATA SOURCES

We performed a systematic review and meta-analysis using a peer-reviewed search strategy combining the themes of vasopressor-dependent shock, critical care, and midodrine and including MEDLINE, Ovid Embase, CINAHL, and Cochrane library databases until September 14, 2023.

STUDY SELECTION

We included studies if they: 1) included patients with vasopressor-dependent shock, 2) were performed in the ICU, 3) evaluated oral midodrine therapy compared with placebo or usual care, and 4) evaluated one of the outcomes of interest.

DATA EXTRACTION

We extracted data independently in duplicate using standardized data abstraction forms, which included the following specific variables: patient characteristics, age, sex, type of ICU, etiology of shock, number of patients, study inclusion and exclusion criteria, and geographical location. We also captured the type, dose, and duration of IV vasopressors, any cointervention used, and outcome data.

DATA SYNTHESIS

We identified seven randomized controlled trials (six included in the pooled analysis) and ten observational studies (four included in the pooled analysis) that met eligibility criteria. Adjunctive midodrine may decrease ICU length of stay (LOS) and there is low certainty of effect on hospital LOS. Midodrine may decrease IV vasopressor support duration, ICU mortality, and hospital mortality. Pooled observational data was based on very low certainty data for all outcomes of interest. The trial sequential analysis-informed required sample size was not met for ICU LOS or IV vasopressor duration and this contributed to Grading of Recommendations, Assessment, Development, and Evaluations assessments of imprecision for both outcomes.

CONCLUSIONS

Adjunctive midodrine may decrease ICU LOS, duration of IV vasopressor therapy, and mortality in critically ill patients. However, required sample sizes was not met to determine our outcomes of interest. Midodrine may increase risk of bradycardia. While midodrine may provide benefit for patient-centered outcomes, due to increased risk of adverse events, further large-scale studies are needed to inform and guide its routine use in the ICU.

Midodrine initiation criteria, dose titration, and adverse effects when administered to treat shock: A systematic review and semi-quantitative analysis

Objective

Systematically examine the literature describing midodrine to treat shock and to summarize current administration and dosing strategies.

Data sources

Structured literature search conducted in MEDLINE (PubMed) from inception through May 10, 2023.

Study Selection and Data Extraction

Abstracts and full texts were assessed for inclusion by two blinded, independent reviewers. English-language publications describing use of midodrine in adult patients with shock were included. Data were extracted by two blinded, independent abstractors using a standardized extraction tool. Quality assessments were completed by paired reviewers using JBI methodology.

Data Synthesis

Fifteen of 698 (2%) screened manuscripts were included with 1,714 patients with a variety of shock types. Seven studies (47%) were retrospective, two (13%) prospective observational, and six (40%) randomized controlled studies. Midodrine was initiated to facilitate intravenous vasopressor (IVP) weaning in most (11, 73%) studies; only two (13%) reported IVP weaning protocol use. Starting doses were 10 mg every 8 hours (4, 27%) or three times a day (3, 20%), 20 mg every 8 hours (2, 13%); six studies (40%) did not report initial midodrine dosing. A midodrine titration protocol was reported in 6 (40%) studies. Thirteen (87%) studies evaluated for bradycardia, identified in 6 (46%) studies among 204 patients; only one (0.5%) patient required midodrine discontinuation. Three (20%) studies reported on hypertension with an incidence of 7-11%. Four (27%) studies assessed for ischemia; 5/1128 (0.4%) patients experienced mesenteric ischemia requiring midodrine discontinuation.

Relevance to Patient care and Clinical Practice

This review explores the pragmatic details involved in initiating, titrating, and weaning midodrine for the bedside clinician and identifies rates of adverse events and complications.

Conclusions

Published literature describing midodrine use for shock is heterogeneous and comprised primarily of low or very low quality data. Future controlled trials addressing the shortcomings identified in this systematic review are warranted.

The Impact of Midodrine Tapering Versus Nontapering Regimens on the Clinical Outcomes of Critically Ill Patients: A Retrospective Cohort Study

BACKGROUND

Midodrine has been used in the intensive care unit (ICU) setting to reduce the time to vasopressor discontinuation. The limited data supporting midodrine use have led to variability in the pattern of initiation and discontinuation of midodrine.

OBJECTIVES

To compare the effectiveness and safety of 2 midodrine discontinuation regimens during weaning vasopressors in critically ill patients.

METHODS

A retrospective cohort study was conducted at King Abdulaziz Medical City. Included patients were adults admitted to ICU who received midodrine after being unable to be weaned from intravenous vasopressors for more than 24 hours. Patients were categorized into two subgroups depending on the pattern of midodrine discontinuation (tapered dosing regimen vs. nontapered regimen). The primary endpoint was the incidence of inotropes and vasopressors re-initiation after midodrine discontinuation.

RESULTS

The incidence of inotropes or vasopressors' re-initiation after discontinuation of midodrine was lower in the tapering group (15.4%) compared with the non-tapering group (40.7%) in the crude analysis as well as regression analysis (odd ratio [OR] = 0.15; 95% CI = 0.03, 0.73, P = 0.02). The time required for the antihypertensive medication(s) initiation after midodrine discontinuation was longer in patients who had dose tapering (beta coefficient (95% CI): 3.11 (0.95, 5.28), P = 0.005). Moreover, inotrope or vasopressor requirement was lower 24 hours post midodrine initiation. In contrast, the two groups had no statistically significant differences in 30-day mortality, in-hospital mortality, or ICU length of stay.

CONCLUSION AND RELEVANCE

These real-life data showed that tapering midodrine dosage before discontinuation in critically ill patients during weaning from vasopressor aids in reducing the frequency of inotrope or vasopressor re-initiation. Application of such a strategy might be a reasonable approach among ICU patients unless contraindicated.

Exploring the Efficacy of Midodrine for Tapering Off Vasopressors

Sepsis and septic shock represent critical conditions, often necessitating vasopressor support in the intensive care unit (ICU). Midodrine, an oral vasopressor, has gathered attention as a potential adjunct to vasopressor therapy, aiming to facilitate weaning and improve clinical outcomes. However, the efficacy of midodrine remains questionable, with conflicting evidence from clinical trials and meta-analyses. This article provides a comprehensive review of the literature on midodrine's role in ICU settings by gathering evidence from multicenter trials, retrospective studies, and meta-analyses. While some studies suggest a limited benefit of midodrine in expediting vasopressor weaning and reducing ICU/hospital stays, others report potential advantages, particularly in reducing mortality rates among septic shock patients. Ongoing efforts aim to address knowledge gaps surrounding midodrine's efficacy and safety.

Droxidopa or Atomoxetine for Refractory Hypotension in Critically Ill Cardiothoracic Surgery Patients

OBJECTIVE

To evaluate the effects of droxidopa or atomoxetine on intravenous (IV) vasoactive agent discontinuation in cardiothoracic intensive care unit (ICU) patients with hypotension refractory to midodrine.

DESIGN

Single-center, retrospective cohort study.

SETTING

Tertiary- and quaternary-care university teaching hospital.

PARTICIPANTS

Included patients who received at least 4 consecutive doses of droxidopa or atomoxetine and remained on concurrent midodrine. Patients were excluded if they received study medication before admission, had clinical deterioration after study medication initiation requiring additional vasoactives/escalation of IV vasoactive dosage for at least 12 hours, had a diagnosis of hepatorenal syndrome, were prisoners, or were pregnant.

INTERVENTIONS

Droxidopa, atomoxetine, or both.

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was time to discontinuation of IV vasoactive agents after initiation of study medication, analyzed using a Kaplan-Meier estimate with the Wilcoxon method, censoring death within 24 hours of the last dose of study medication. No adjustment for repetitive analyses was made, as the analysis was hypothesis-generating. Of the 72 charts reviewed, 45 patients met inclusion criteria (18 atomoxetine, 17 droxidopa, and 10 both). There were no differences in median time to discontinuation of IV vasoactive agents (21.9 days v 8.0 days v 13.9 days, respectively; p = 0.259) or ICU or hospital length of stay between groups. A higher percentage of patients who survived to hospital discharge received both study medications or droxidopa alone (90% v 76.5%) than atomoxetine alone (44.4%, p = 0.028).

CONCLUSIONS

Droxidopa and atomoxetine are oral vasoactive agents with potential mechanisms to facilitate IV vasopressor weaning for patients in the ICU with hypotension refractory to midodrine, but further prospective research is needed.

Midodrine in end-stage heart failure

It is estimated that 5% of patients with heart failure (HF) will progress to end-stage disease refractory to medical therapy and might require prolonged hospitalisation with inotropic support. We present the case of a patient with end-stage HF who was admitted with cardiogenic shock. During his hospitalisation, he required prolonged intravenous vasopressor therapy due to refractory hypotension. He did not qualify for heart transplantation or left ventricular-assist device strategies. Midodrine was started as a last resort attempt to wean off vasopressors. After 5 days of therapy, the patient was weaned entirely off vasopressors and was discharged home for hospice care. By the time of discharge, he was tolerating low-dose carvedilol along with midodrine. We propose midodrine as a reasonable alternative for patients with end-stage HF with reduced ejection fraction and refractory hypotension, who are dependent on intravenous vasoactive drugs and are not candidates for advanced HF therapies.

Oral midodrine does not expedite liberation from protracted vasopressor infusions: A case-control study

Vasopressor dependence is a common problem affecting patients in the recovery phase of critical illness, often necessitating intensive care unit (ICU) admission and other interventions which carry associated risks. Midodrine is an orally administered vasopressor which is commonly used off-label to expedite weaning from vasopressor infusions and facilitate discharge from ICU. We performed a single-centre, case-control study to assess whether midodrine accelerated liberation from vasopressor infusions in patients who were vasopressor dependent. Cases were identified at the discretion of treating intensivists and received 20 mg oral midodrine every eight h from enrolment. Controls received placebo. Data on duration and dose of vasopressor infusion, haemodynamics and adverse events were collected. Between 2012 and 2019, 42 controls and 19 cases were recruited. Cases had received vasopressor infusions for a median of 94 h versus 29.3 h for controls, indicating prolonged vasopressor dependence amongst cases. Midodrine use in cases was not associated with faster weaning of intravenous (IV) vasopressors (26 h versus 24 h for controls, P = 0.51), ICU or hospital length of stay after adjustment for confounders. Midodrine did not affect mean heart rate but was associated with bradycardia. This case-control study demonstrates that midodrine has limited efficacy in expediting weaning from vasopressor infusions in patients who have already received relatively prolonged courses of these infusions.

Midodrine use in critically ill patients: a narrative review

Midodrine is a peripherally acting, oral α-agonist that is increasingly used in intensive care units despite conflicting evidence for its effectiveness. It has pharmacological effects on blood vessels as well as pupillary, cardiac, renal, gastrointestinal, genitourinary, lymphatic and skin tissue. It has approval for use as a treatment for orthostatic hypotension, but a surge in interest over the past decade has prompted its use for a growing number of off-label indications. In critically ill patients, midodrine has been used as either an adjunctive oral therapy to wean vasoplegic patients off low dose intravenous vasopressor infusions, or as an oral vasopressor agent to prevent or minimise the need for intravenous infusion. Clinical trials have mostly focused on midodrine as an intravenous vasopressor weaning agent. Early retrospective studies supported its use for this indication, but more recent randomised controlled trials have largely refuted this practice. Key questions remain on its role in managing critically ill patients before intensive care admission, during intensive care stay, and following discharge. This narrative review presents a comprehensive overview of midodrine use for the critical care physician and highlights why lingering questions around ideal patient selection, dosing, timing of initiation, and efficacy of midodrine for critically ill patients remain unanswered.

Contemporary hemodynamic management of acute spinal cord injuries with intravenous and enteral vasoactive agents: A narrative review

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

The pathophysiology and hemodynamic management of acute spinal cord injuries, including the use of intravenous and enteral vasoactive agents, are reviewed.

SUMMARY

Spinal cord injuries are devastating neurological insults that in the acute setting lead to significant hemodynamic disturbances, including hypotension and bradycardia, that are influenced by the level of injury. High thoracic (usually defined as at or above T6) and cervical injuries often manifest with hypotension and bradycardia due to destruction of sympathetic nervous system activity and unopposed vagal stimulation to the myocardium, whereas lower thoracic injuries tend to result in hypotension alone due to venous pooling. Initial management includes maintaining euvolemia with crystalloids and maintaining or augmenting mean arterial pressure with the use of intravenous vasoactive agents to improve neurological outcomes. Choice of vasopressor should be based on patient-specific factors, particularly level of injury and presenting hemodynamics. This review includes the most recent literature on intravenous vasopressors as well as the limited evidence supporting the use of enteral vasoactive agents. Enteral vasoactive agents may be considered, when clinically appropriate, as a strategy to wean patients off of intravenous agents and facilitate transfer outside of the intensive care unit.

CONCLUSION

The hemodynamic management of acute spinal cord injuries often requires the use of vasoactive agents to meet mean arterial pressure goals and improve neurological outcomes. Patient-specific factors must be considered when choosing intravenous and enteral vasoactive agents.

A pilot, feasibility, randomised controlled trial of midodrine as adjunctive vasopressor for low-dose vasopressor-dependent hypotension in intensive care patients: The MAVERIC study

PURPOSE

To assess the feasibility and physiological efficacy of adjunctive midodrine in patients with vasopressor-dependent hypotension.

MATERIALS AND METHODS

This was a pilot, open label, randomised controlled trial. Patients were enrolled from two tertiary intensive care units on low dose intravenous vasopressor therapy for more than 24 h. We randomly assigned patients to receive either adjunctive midodrine (10 mg every 8 h) or usual care. The primary efficacy outcome was time to cessation of intravenous vasopressor therapy. Secondary outcomes included protocol compliance, ICU and hospital length of stay.

RESULTS

We screened 381 patients over 22-months and enrolled 62 (32 in midodrine group, 30 in usual care group). Median time to cessation of vasopressor infusion was 16.5 h for midodrine vs 19 h for usual care (p = 0.22). Time in ICU (50 [25.50, 74.00] hours for midodrine v 59 [38.50, 93.25] hours for usual care, p = 0.14) and hospital length of stay (9 days vs. 7.5 days, p = 0.92) were similar. Protocol compliance was 96.9%. One patient ceased midodrine early due to symptomatic bradycardia.

CONCLUSIONS

Adjunctive midodrine therapy was feasible with acceptable compliance, duration of therapy, and safety profile. However, at the chosen dose, there was no evidence of physiological or clinical efficacy.

Midodrine improves clinical and economic outcomes in patients with septic shock: a randomized controlled clinical trial

BACKGROUND

Prolonged use of intravenous (IV) vasopressors in patients with septic shock can lead to deleterious effects.

AIMS

This study assessed the impact of midodrine administration on weaning off IV vasopressors and its economic value.

METHODS

It is a prospective randomized controlled study of 60 resuscitated patients with septic shock who demonstrated clinical stability on low-dose IV vasopressors for at least 24 h. Participants were randomized into two groups: norepinephrine (IV norepinephrine) and midodrine (IV norepinephrine + oral midodrine 10 mg thrice a day). A cost comparison was applied based on the outcomes of both groups.

RESULTS

The median duration of norepinephrine administration in the midodrine and norepinephrine groups was 4 and 6 days, respectively (p = 0.001). Norepinephrine weaning time was significantly less in the midodrine versus norepinephrine groups (26 and 78.5 h, respectively; p < 0.001). Mortality was 43.3% versus 73.3% in the midodrine and norepinephrine groups, respectively (p = 0.018). The mean length of stay was comparable in the two groups. The midodrine group showed cost-saving results versus the norepinephrine group.

CONCLUSION

The use of midodrine in septic shock patients significantly reduced IV norepinephrine duration, weaning period during the septic shock recovery phase, and mortality. Thus, the use of midodrine is dominant with less cost, better outcome and a cost-saving option in terms of budget impact analysis. This study was registered at clinicaltrials.gov (NCT 03,911,817) on April 11, 2019.

Vasopressor-Sparing Strategies in Patients with Shock: A Scoping-Review and an Evidence-Based Strategy Proposition

Despite the abundant literature on vasopressor therapy, few studies have focused on vasopressor-sparing strategies in patients with shock. We performed a scoping-review of the published studies evaluating vasopressor-sparing strategies by analyzing the results from randomized controlled trials conducted in patients with shock, with a focus on vasopressor doses and/or duration reduction. We analyzed 143 studies, mainly performed in septic shock. Our analysis demonstrated that several pharmacological and non-pharmacological strategies are associated with a decrease in the duration of vasopressor therapy. These strategies are as follows: implementing a weaning strategy, vasopressin use, systemic glucocorticoid administration, beta-blockers, and normothermia. On the contrary, early goal directed therapies, including fluid therapy, oral vasopressors, vitamin C, and renal replacement therapy, are not associated with an increase in vasopressor-free days. Based on these results, we proposed an evidence-based vasopressor management strategy.

Impact of Adjuvant Use of Midodrine to Intravenous Vasopressors: A Systematic Review and Meta-Analysis

Purpose

To evaluate the efficacy and safety of midodrine use in intensive care units (ICU) to facilitate weaning off intravenous vasopressors (IVV).

Methods

We searched PubMed/MEDLINE, Cochrane library, and Google Scholar (inception through October 18^th, 2020) for studies evaluating adjuvant use of midodrine to IVV in the ICU. The outcomes of interest were ICU length of stay (LOS), hospital LOS, mortality, IVV reinstitution, ICU readmission, and bradycardia. Estimates were pooled using the random-effects model. We reported effect sizes as standardized mean difference (SMD) for continuous outcomes and risk ratios (RRs) for other outcomes with a 95% confidence interval (CI).

Results

A total of 6 studies were found that met inclusion criteria and had sufficient data for our quantitative analysis (1 randomized controlled trial and 5 retrospective studies). A total of 2,857 patients were included: 600 in the midodrine group and 2,257 patients in the control group. Midodrine use was not associated with a significant difference in ICU LOS (SMD 0.16 days; 95% CI −0.23 to 0.55), hospital LOS (SMD 0.03 days; 95% CI −0.33 to 0.0.39), mortality (RR 0.87; 95% CI 0.52 to 1.46), IVV reinstitution (RR 0.47; 95% CI 0.17 to 1.3), or ICU readmission (RR 1.03; 95% CI 0.71 to 1.49) when compared to using only IVV. However, there were higher trends of bradycardia with midodrine use that did not reach significance (RR 7.64; 95% CI 0.23 to 256.42).

Conclusion

This meta-analysis suggests that midodrine was not associated with a significant decrease in ICU LOS, hospital LOS, mortality, or ICU readmissions.

Potential risks in using midodrine for persistent hypotension after cardiac surgery: a comparative cohort study

Background

Persistent hypotension is a frequent complication after cardiac surgery with cardiopulmonary bypass (CPB). Midodrine, an orally administered alpha agonist, could potentially reduce intravenous vasopressor use and accelerate ICU discharge of otherwise stable patients. The main objective of this study was to explore the clinical impacts of administering midodrine in patients with persistent hypotension after CPB. Our hypothesis was that midodrine would safely accelerate ICU discharge and be associated with more days free from ICU at 30 days.

Results

We performed a retrospective cohort study that included all consecutive patients having received midodrine while being on vasopressor support in the ICU within the first week after cardiac surgery with CPB, between January 2014 and January 2018 at the Montreal Heart Institute. A contemporary propensity score matched control group that included patients who presented similarly prolonged hypotension after cardiac surgery was formed.

After matching, 74 pairs of patients (1:1) fulfilled inclusion criteria for the study and control groups. Midodrine use was associated with fewer days free from ICU (25.8 [23.7–27.1] vs 27.2 [25.9–28] days, p = 0.002), higher mortality (10 (13.5%) vs 1 (1.4%), p = 0.036) and longer ICU length of stay (99 [68–146] vs 68 [48–99] hours, p = 0.001). There was no difference in length of intravenous vasopressors (63 [40–87] vs 44 [26–66] hours, p = 0.052), rate of ICU readmission (6 (8.1%) vs 2 (2.7%), p = 0.092) and occurrence of severe kidney injury (11 (14.9%) vs 10 (13.5%) patients, p = 0.462) between groups.

Conclusion

The administration of midodrine for sustained hypotension after cardiac surgery with CPB was associated with fewer days free from ICU and higher mortality. Routine prescription of midodrine to hasten ICU discharge after cardiac surgery should be used with caution until further prospective studies are conducted.

Clinical utility of midodrine and methylene blue as catecholamine-sparing agents in intensive care unit patients with shock

Shock is common in the intensive care unit, affecting up to one third of patients. Treatment of shock is centered upon managing hypotension and ensuring adequate perfusion via administration of fluids and catecholamine vasopressors. Due to the risks associated with catecholamine vasopressors, interest has grown in using catecholamine-sparing agents such as midodrine and methylene blue. Midodrine is an orally administered alpha-1 adrenergic agonist while methylene blue is an intravenously administered blue dye used to restore vascular tone and increase blood pressure. Separate MEDLINE, Scopus, and Embase database searches were conducted to assess literature revolving around these agents. Examples of search terms included "midodrine", "methylene blue", "critically ill", "shock", and "catecholamine-sparing." Several studies have evaluated their use in patients with shock and found potential benefits in terms of causing significant elevations in blood pressure and hastening catecholamine vasopressor discontinuation with few adverse effects; however, robust evidence is lacking for these off-label indications. Because of the variety of dosing strategies used and the incongruences between patient populations, it is also challenging to define finite recommendations. This review aims to summarize current evidence for the use of midodrine and methylene blue as catecholamine-sparing agents in critically ill patients with resolving or refractory shock.

Norepinephrine and Vasopressin Compared With Norepinephrine and Epinephrine in Adults With Septic Shock

Background: The optimal adjuvant vasopressor to norepinephrine in septic shock remains controversial. Objective: To compare durations of shock-free survival between adjuvant vasopressin and epinephrine. Methods: A retrospective, single-center, matched cohort study of adults with septic shock refractory to norepinephrine was conducted. Patients receiving norepinephrine not at target mean arterial pressure (MAP; 65 mm Hg) were initiated on vasopressin or epinephrine to raise MAP to target. Vasopressin-exposed patients were matched to epinephrine-exposed patients using propensity scores. Mortality outcomes were examined using multivariable Poisson regression with robust variance estimation. Results: Of 166 patients, 96 (entire cohort) were included in the propensity score-matched cohort. Shock-free survival durations in the first 7 days were similar between epinephrine- and vasopressin-exposed patients in the matched cohort (median = 13.2 hours, interquartile range [IQR] = 0-121.0, vs median = 41.3 hours, IQR = 0-125.9; P = 0.51). Seven- and 28-day mortality rates were similar in the matched cohort (7-day: 47.9% vs 39.6%, P = 0.35; 28-day: 56.3% vs 58.3%, P = 0.84). Mortality rates were similar between epinephrine- and vasopressin-exposed patients in propensity score-matched regression models with and without adjustments at 7 (relative risk [RR] = 1.28, 95% CI = 0.92-1.79; RR = 1.21, 95% CI = 0.81-1.81) and 28 days (RR = 1.04, 95% CI = 0.81-1.34; RR = 0.96, 95% CI = 0.69-1.34). Conclusion and Relevance: Shock-free survival durations were similar in matched epinephrine- and vasopressin-exposed groups. Adjuvant epinephrine or vasopressin alongside norepinephrine to raise MAP to target requires further investigation.