Hemodynamic Response to Vasopressin Dosage of 0.03 Units/Min vs. 0.04 Units/Min in Patients With Septic Shock

asopressin nitiation as a econd-Line Vasoressor in Early eptic hock (VISPSS)

BACKGROUND

Vasopressin is recommended as a second-line vasoactive agent for the management of septic shock; however, a paucity of data to guide its optimal use remains. The aim was to evaluate the effect of time-to vasopressin initiation and norepinephrine (NE) dose at vasopressin initiation on clinical outcomes in patients presenting with septic shock.

METHODS

This was a multi-centered, retrospective, observational study conducted in patients with septic shock. Patients were divided into 2 groups: patients initiated on vasopressin when NE-equivalent dose (NEE) < 0.25 mcg/kg/min or ≥ 0.25 mcg/kg/min. The primary outcome was time-to-vasopressor discontinuation (hours). Secondary outcomes included 28-day in-hospital mortality, intensive care unit (ICU) length of stay (LOS), fluid balance after 72 hours, and the change in NEE at 12 hours.

RESULTS

A total of 302 patients were included in this study. After propensity-score matching, 73 patients in each group were identified for analysis. There was no significant difference in the time-to-vasopressor discontinuation (hours) between the groups (88.8 [55-187.5] vs 86.7 [47-172]); p = 0.7815). Fluid balance (mL) at 72 hours was significantly lower when vasopressin was initiated at NEE < 0.25 mcg/kg/min (1769 [71-7287] vs 5762 [1463-8813]; p = 0.0077). A multivariable linear regression showed shorter time to shock resolution with earlier vasopressin initiation, defined as within 4 hours (p < 0.05).

CONCLUSION

In this propensity-score matched cohort, vasopressin initiation at NEE < 0.25 mcg/kg/min was not associated with shorter vasopressor duration. There was a lower fluid balance at 72 hours when vasopressin was initiated at lower NE doses.

Effect of Early Administration of Vasopressin on New-Onset Arrhythmia Development in Patients With Septic Shock: A Retrospective, Observational Cohort Study

Background: Adjunctive vasopressin use in septic shock reduces catecholamine requirements and is associated with a lower incidence of new-onset arrhythmias (NOAs). The association of vasopressin timing on NOA development is ill-described. Objective: To determine whether early administration of vasopressin was associated with a lower incidence of NOA in septic shock patients. Methods: A retrospective analysis of intensive care unit (ICU) patients at a large, academic medical center. Septic shock patients who required vasopressin and norepinephrine were eligible for inclusion. Patients were excluded for receipt of other vasoactive agents, history of cardiac arrhythmias, or outside hospital admission. Early vasopressin was defined as receipt within 6 hours of septic shock onset. The primary outcome was incidence of NOA. Results: In total, 436 patients, 220 (50.4%) in the early and 216 (49.6%) in the late vasopressin group, were included. Early vasopressin was not associated with a lower incidence of NOA compared with late vasopressin (9% vs 7%, median absolute difference [95% confidence interval, CI]: -2.1 [-7.2, 3.0], P = 0.41). Early vasopressin patients were observed to have shorter shock duration (2 vs 4 days, median absolute difference [95% CI]: 2 [1, 2], P < 0.001), and ICU length of stay (6 vs 7 days, median absolute difference [95% CI]: 1 [0, 2], P = 0.02). Conclusions and Relevance: Early vasopressin use was not associated with a lower incidence of NOA. Additional studies are needed to elucidate the effect of vasopressin timing on NOA and other clinical outcomes.

Influence of Timing and Catecholamine Requirements on Vasopressin Responsiveness in Critically ill Patients with Septic Shock

Introduction: Despite its widespread use, there is a paucity of data to guide the optimal use of arginine vasopressin (AVP) in critically ill patients with septic shock. Methods: This multicenter retrospective cohort study conducted in critically ill adults sought to evaluate the role of catecholamine requirements and timing on responsiveness to AVP. Responsiveness was defined as both a decrease in ≥ 50% of catecholamine requirements and no decrease in mean arterial pressure (MAP) at 4 hours post-AVP initiation. Primary outcomes of interest included the proportion of patients who started AVP within 4 hours after starting catecholamine therapy, as well as baseline norepinephrine (NE) equivalents (< 15, 15-39, or ≥ 40 mcg/min). Multivariate analyses and logistic regression were performed to identify other factors associated with AVP responsiveness. Results: There were 300 patients included in this study, with 74 patients being responders and 226 being non-responders. There was no significant difference in the number of patients who received AVP within 4 hours from catecholamine initiation between responders and non-responders (35% vs. 42%, P = 0.29). There were more patients in the non-responder group requiring ≥ 40 mcg/min of NE equivalents at AVP initiation (30% vs. 16%, P = 0.023). Stress dose steroid use was less common in responders (35% vs. 52%, P = 0.011), which was consistent with logistic regression analysis (OR 0.56, 95% 0.32-0.98, P = 0.044). Clinical outcomes between responders and non-responders were similar, apart from ICU (5.4% vs. 19.5%) and hospital (5.4% vs. 20.4%) mortality being lower in responders (P = 0.0032 and P = 0.0002, respectively). Conclusion: Shorter times to AVP initiation was not associated with responsiveness at 4 hours post-catecholamine initiation, although non-responders tended to require higher doses of NE equivalents at time of AVP initiation. Concomitant corticosteroids were associated with a lower likelihood of AVP responsiveness.

Vasopressin Loading for Refractory Septic Shock: A Preliminary Analysis of a Case Series

Background: Vasopressin is one of the strong vasopressor agents associated with ischemic events. Responses to the administration of vasopressin differ among patients with septic shock. Although the administration of a high dose of vasopressin needs to be avoided, the effects of bolus loading have not yet been examined. Since the half-life of vasopressin is longer than that of catecholamines, we hypothesized that vasopressin loading may be effective for predicting responses to its continuous administration. Methods: We retrospectively analyzed consecutive cases of septic shock for which vasopressin was introduced with loading under noradrenaline at >0.2 μg/kg/min during the study period. Vasopressin was administered in a 1 U bolus followed by its continuous administration at 1 U/h. The proportion of patients with a negative catecholamine index (CAI) change 6 h after the introduction of vasopressin was set as the primary outcome. We defined non-responders for exploration as those with a mean arterial pressure change <18 mmHg 1 min after vasopressin loading, among whom none had a change in CAI <0. Results: Twenty-one consecutive cases were examined in the present study, and included 14 responders and 7 non-responders. The primary outcome accounted for 71.4% of responders and 0% of non-responders, with a significant difference (p = 0.0039). Median CAI changes 2, 4, and 6 h after the administration of vasopressin were 0, -5, and -10 in responders and +20, +10, and +10 in non-responders, respectively. CAI was not reduced in any non-responder. Outcomes including mortality were not significantly different between responders and non-responders. Digital ischemia (1/21) and mesenteric ischemia (1/21) were observed. Conclusions: Vasopressin loading may predict responses to its continuous administration in septic shock patients. Further investigations involving a safety analysis are needed.