Association Between Vasopressin Rebranding and Utilization in Patients With Septic Shock

ADJUNCTIVE VASOPRESSORS AND SHORT-TERM MORTALITY IN ADULTS WITH SEPTIC SHOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT

Background: Adjunctive vasopressors are added to norepinephrine in one-third of adults with septic shock in the United States. However, effectiveness of this approach is unclear, and treatment recommendations are based on indirect evidence. We sought to synthesize the direct evidence for adjunctive vasopressor administration in adults with septic shock. Methods: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception to June 7, 2023. We included randomized clinical trials of adults with septic shock comparing adjunctive treatment with a vasopressin analogue, angiotensin II, methylene blue, hydroxocobalamin, or catecholamine analog to standard care vasopressors. The primary outcome was short-term mortality (at or before 28-30 days or intensive care discharge). Secondary outcomes included kidney replacement therapy, digital/peripheral ischemia, and venous thromboembolism. Random-effects meta-analyses were conducted to derive risk ratios (RRs) and 95% CIs. The certainty of the evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. Results: Of 6,763 records, 17 trials (3,813 participants) were included. Compared with standard care, adjunctive vasopressor administration may reduce short-term mortality risk (RR, 0.92 [95% CI, 0.85-1.00], low certainty, 17 trials [3618 participants]) and likely reduces kidney replacement therapy receipt (RR, 0.92 [95% CI, 0.84-1.01], moderate certainty, eight trials [2,408 participants]). Adjunctive vasopressor treatment may increase risk of digital/peripheral ischemia (RR, 2.44 [95% CI, 1.17-5.10], low certainty, nine trials [2,981 participants]) and venous thromboembolism (RR, 16.48 [95% CI, 0.96-283.17], low certainty, one trial [321 participants]). There was some evidence that the pooled estimate for short-term mortality was different (interaction P = 0.13) for trials adjudicated as low risk of bias (RR, 0.95 [95% CI, 0.87-1.05]) compared with trials adjudicated as some concerns or high risk of bias (RR, 0.82 [95% CI, 0.69-0.97]). The findings were robust to multiple sensitivity and subgroup analyses. Conclusions: In adults with septic shock, adjunctive vasopressors may lower short-term death risk and likely lower kidney replacement therapy risk, but may increase risk of adverse effects. In the United States, adjunctive vasopressor use prevalence in septic shock is disconnected from the low evidence certainty for a favorable mortality-to-risk profile.

Optimizing Vasopressin Use and Initiation Timing in Septic Shock: A Narrative Review

TOPIC IMPORTANCE

This review discusses the rationale for vasopressin use, summarizes the results of clinical trials evaluating vasopressin, and focuses on the timing of vasopressin initiation to provide clinicians guidance for optimal adjunctive vasopressin initiation in patients with septic shock.

REVIEW FINDINGS

Patients with septic shock require vasoactive agents to restore adequate tissue perfusion. After norepinephrine, vasopressin is the suggested second-line adjunctive agent in patients with persistent inadequate mean arterial pressure. Vasopressin use in practice is heterogeneous likely because of inconsistent clinical trial findings, the lack of specific recommendations for when it should be used, and the high drug acquisition cost. Despite these limitations, vasopressin has demonstrated price inelastic demand, and its use in the United States has continued to increase. However, questions remain regarding optimal vasopressin use in patients with septic shock, particularly regarding patient selection and the timing of vasopressin initiation.

SUMMARY

Experimental studies evaluating the initiation timing of vasopressin in patients with septic shock are limited, and recent observational studies have revealed an association between vasopressin initiation at lower norepinephrine-equivalent doses or lower lactate concentrations and lower mortality.

Echocardiographic profiles and hemodynamic response after vasopressin initiation in septic shock: A cross-sectional study

PURPOSE

Vasopressin, used as a catecholamine adjunct, is a vasoconstrictor that may be detrimental in some hemodynamic profiles, particularly left ventricular (LV) systolic dysfunction. This study tested the hypothesis that echocardiographic parameters differ between patients with a hemodynamic response after vasopressin initiation and those without a response.

METHODS

This retrospective, single-center, cross-sectional study included adults with septic shock receiving catecholamines and vasopressin with an echocardiogram performed after shock onset but before vasopressin initiation. Patients were grouped by hemodynamic response, defined as decreased catecholamine dosage with mean arterial pressure ≥ 65 mmHg six hours after vasopressin initiation, with echocardiographic parameters compared. LV systolic dysfunction was defined as LV ejection fraction (LVEF) <45%.

RESULTS

Of 129 included patients, 72 (56%) were hemodynamic responders. Hemodynamic responders, versus non-responders, had higher LVEF (61% [55%,68%] vs. 55% [40%,65%]; p = 0.02) and less-frequent LV systolic dysfunction (absolute difference  -16%; 95% CI -30%,-2%). Higher LVEF was associated with higher odds of hemodynamic response (for each LVEF 10%, response OR 1.32; 95% CI 1.04-1.68). Patients with LV systolic dysfunction, versus without LV systolic dysfunction, had higher mortality risk (HR(t) = e[0.81-0.1*t]; at t = 0, HR 2.24; 95% CI 1.08-4.64).

CONCLUSIONS

Pre-drug echocardiographic profiles differed in hemodynamic responders after vasopressin initiation versus non-responders.

Extended Stability of Vasopressin Injection in Polyvinyl Chloride Bags and Polypropylene Syringes and Its Impact on Critically Ill Patient Care and Medication Waste

Background. Vasopressin is frequently utilized for a variety of shock states in critically ill patients. Short stability (≤24 hours) after intravenous admixture with current manufacturer labeling requires just in time preparation and may lead to delays in therapy and increased medication waste. We aimed to evaluate vasopressin stability in 0.9% sodium chloride stored in polyvinyl chloride bags and polypropylene syringes for up to 90 days. Additionally, we evaluated the impact of extended stability on the time to administration and cost savings from reduced medical waste at an academic medical center. Methods. Dilutions of vasopressin to concentrations of 0.4 and 1.0 unit/mL were performed under aseptic conditions. The bags and syringes were stored at room temperature (23°C-25°C) or under refrigeration (3°C-5°C). Three samples of each preparation and storage environment were analyzed on days 0, 2, 14, 30, 45, 60, and 90. Physical stability was performed by visual examination. The pH was assessed at each point and upon final degradation evaluation. Sterility of the samples was not assessed. Chemical stability of vasopressin was evaluated using liquid chromatography with tandem mass spectrometry. Samples were considered stable if there was <10% degradation of the initial concentration. Results. Vasopressin diluted to 0.4 and 1.0 unit/mL with 0.9% sodium chloride injection was physically stable throughout the study. No precipitation was observed. At days 2, 14, 30, 45, 60, and 90 all bags and syringes diluted to 0.4 units/mL had <10% degradation. Vasopressin diluted to 1 unit/mL and stored under refrigeration had <10% degradation at all measured days, but when stored under room temperature was found to have >10% degradation at day 30. Implementation of a batching process resulted in reduced waste ($185 300) and improved time to administration (26 vs 4 minutes). Conclusion. Vasopressin diluted to a concentration of 0.4 units/mL with 0.9% sodium chloride injection is stable for 90 days at room temperature and under refrigeration. When diluted to 1.0 unit/mL with 0.9% sodium chloride injection it is stable for 90 days under refrigeration. Use of extended stability and sterility testing to batch prepare infusions may lead to improved time to administration and cost savings from reduced medication waste.

The pharmacotherapeutic options in patients with catecholamine-resistant vasodilatory shock

INTRODUCTION

Septic and vasoplegic shock are common types of vasodilatory shock (VS) with high mortality. After fluid resuscitation and the use of catecholamine-mediated vasopressors (CMV), vasopressin, angiotensin II, methylene blue (MB) and hydroxocobalamin can be added to maintain blood pressure.

AREAS COVERED

VS treatment utilizes a phased approach with secondary vasopressors added to vasopressor agents to maintain an acceptable mean arterial pressure (MAP). This review covers additional vasopressors and adjunctive therapies used when fluid and catecholamine-mediated vasopressors fail to maintain target MAP.

EXPERT OPINION

Evidence supporting additional vasopressor agents in catecholamine resistant VS is limited to case reports, series, and a few randomized control trials (RCTs) to guide recommendations. Vasopressin is the most common agent added next when MAPs are not adequately supported with CMV. VS patients failing fluids and vasopressors with cardiomyopathy may have cardiotonic agents such as dobutamine or milrinone added before or after vasopressin. Angiotensin II, another class of vasopressor is used in VS to maintain adequate MAP. MB and/or hydoxocobalamin, vitamin C, thiamine and corticosteroids are adjunctive therapies used in refractory VS. More RCTs are needed to confirm the utility of these drugs, at what doses, which combinations and in what order they should be given.

Why So Salty? Transient Diabetes Insipidus After Discontinuation of Vasopressin

In recent years, vasopressin has been increasingly used as an early treatment of vasopressor-refractory septic shock. In this article, we describe 2 episodes of transient diabetes insipidus after vasopressin for the treatment of septic shock was discontinued, which adds to a modest number of case studies reporting the same phenomenon. With the anticipated continued use of vasopressin in intensive care units, it can be expected that this adverse effect will occur with some frequency. Awareness and early recognition of this phenomenon can lead to prompt diagnosis and treatment.