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.

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.

Incidence of Hypotension Associated With Two Different Vasopressin Discontinuation Strategies in the Recovery Phase of Septic Shock

INTRODUCTION

Safe and effective vasopressor withdrawal strategies during the recovery phase of septic shock lack consensus and are not addressed in clinical practice guidelines. The purpose of this study was to compare the incidence of clinically relevant hypotension associated with different vasopressin (AVP) discontinuation strategies.

METHODS

This was a single-center, retrospective, cohort study, conducted at a university medical center over a three-year period. Adult patients ≥18 years with septic shock were included in the study. Patients were stratified into two groups; patients incrementally weaned from AVP and patients in which AVP was abruptly discontinued. The primary endpoint was to compare the incidence of clinically relevant hypotension between study groups up to 24 hours following discontinuation. Secondary analyses included the incidence of any hypotensive event up to 24 hours after AVP cessation, intensive care unit and hospital length of stay, and in-hospital mortality.

RESULTS

A total of 74 patients (n = 46 AVP wean and n = 28 AVP no-wean) met inclusion criteria and were included in the study. The primary outcome was not statistically different between groups. Clinically relevant hypotension occurred in 24 patients (52.3%) and 16 patients (57.1%) in the AVP wean and AVP no-wean groups, respectively (P = .68). There were no significant differences in any secondary clinical outcome between the two study groups.

CONCLUSION

No differences were found in the incidence of clinically relevant hypotension, length of stay, or mortality between AVP weaning and no-weaning discontinuation strategies. These findings suggest incremental weaning and abrupt withdrawal of AVP are both acceptable discontinuation strategies.

Association of Arterial pH With Hemodynamic Response to Vasopressin in Patients With Septic Shock: An Observational Cohort Study

OBJECTIVES

Vasopressin is reported to retain vasoconstrictive activity in the setting of acidemia, but preclinical models are inconsistent and studies have not evaluated the clinical effectiveness of vasopressin based on arterial pH. This study sought to determine the association between arterial pH and blood pressure after vasopressin initiation in septic shock.

DESIGN

This retrospective, multicenter, observational cohort study evaluated the association of arterial pH at the time of vasopressin initiation with hemodynamic response to vasopressin and change in catecholamine dose after vasopressin initiation. Hemodynamic response was defined as a catecholamine dose decrease with mean arterial pressure greater than or equal to 65 mm Hg at 6 hours after vasopressin initiation.

SETTING

Patients from eight hospitals in a health system were evaluated.

PATIENTS

Patients with septic shock initiated on vasopressin as a catecholamine adjunct between January 2012 and November 2017 were screened for inclusion.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 1,350 patients were included. At the time of vasopressin initiation patients were severely ill with arterial pH 7.28 ± 0.13, Sequential Organ Failure Assessment 14.1 ± 3.5, lactate 5.6 ± 4.6 mmol/L, and norepinephrine-equivalent catecholamine dose 32.3 ± 25.4 µg/min. After adjusting for lactate and Sequential Organ Failure Assessment with multivariable logistic regression, lower arterial pH was independently associated with lower odds of hemodynamic response to vasopressin (for each 0.1 unit arterial pH was below 7.40, response odds ratio 0.79; 95% CI, 0.72-0.87). For each 0.1 unit the pH was below 7.40 at vasopressin initiation, the norepinephrine-equivalent catecholamine dose increased by 1.5 µg/min (95% CI, 0.5-2.5 µg/min) at 1 hour, and increased by 2.5 µg/min (95% CI, 1.4-3.5 µg/min) at 6 hours after vasopressin initiation.

CONCLUSIONS

Compared with higher arterial pH, patients with septic shock and low arterial pH had lower odds of vasopressin response and higher catecholamine doses after vasopressin initiation. Similar to other vasopressors, the clinical effectiveness of vasopressin appears to be impaired in the setting of acidemia.

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

BACKGROUND

Arginine vasopressin (AVP) is suggested as an adjunct to norepinephrine in patients with septic shock. Guidelines recommend an AVP dosage up to 0.03 units/min, but 0.04 units/min is commonly used in practice based on initial studies. This study was designed to compare the incidence of hemodynamic response between initial fixed-dosage AVP 0.03 units/min and AVP 0.04 units/min.

METHODS

This retrospective, multi-hospital health system, cohort study included adult patients with septic shock receiving AVP as an adjunct to catecholamine vasopressors. Patients were excluded if they received an initial dosage other than 0.03 units/min or 0.04 units/min, or AVP was titrated within the first 6 hours of therapy. The primary outcome was hemodynamic response, defined as a mean arterial pressure ≥65 mm Hg and a decrease in catecholamine dosage at 6 hours after AVP initiation. Inverse probability of treatment weighting (IPTW) based on the propensity score for initial AVP dosage receipt was utilized to estimate adjusted exposure effects.

RESULTS

Of the 1536 patients included in the observed data, there was a nearly even split between initial AVP dosage of 0.03 units/min (n = 842 [54.8%]) and 0.04 units/min (n = 694 [45.2%]). Observed patients receiving AVP 0.03 units/min were more frequently treated at the main campus academic medical center (96.3% vs. 52.2%, p < 0.01) and in a medical intensive care unit (87.4% vs. 39.8%, p < 0.01). The IPTW analysis included 1379 patients with achievement of baseline covariate balance. There was no evidence for a difference between groups in the incidence of hemodynamic response (0.03 units/min 50.0% vs. 0.04 units/min 53.1%, adjusted relative risk 1.06 [95% CI 0.94, 1.20]).

CONCLUSIONS

Initial AVP dosing varied by hospital and unit type. Although commonly used, an initial AVP dosage of 0.04 units/min was not associated with a higher incidence of early hemodynamic response to AVP in patients with septic shock.

Abrupt Discontinuation Versus Down-Titration of Vasopressin in Patients Recovering from Septic Shock

PURPOSE

To compare patient outcomes based on management of arginine vasopressin (AVP) during the recovery phase of septic shock (abrupt vs. tapering discontinuation).

PATIENTS AND METHODS

Multicenter, retrospective cohort study of patients receiving AVP with concomitant norepinephrine for septic shock. Primary outcome measure was time to intensive care unit (ICU) discharge (from decision to titrate or stop AVP). Secondary outcomes included ICU and hospital mortality, and incidence of hypotension.

RESULTS

A total of 958 (73%) abrupt discontinuation and 360 (27%) down-titration patients were included. Patient characteristics and septic shock treatment courses were similar between groups. Median time to ICU discharge was similar between abrupt discontinuation (7.9 days, 95% CI 7.2-8.7 days) and tapered patients (7.3 days, 95% CI 6.3-9.3 days, P = 0.60). After controlling for baseline discrepancies, down-titration was not an independent predictor of time to ICU discharge (HR = 0.99, 95% CI: 0.85-1.15, P = 0.91). There was no difference in ICU mortality (21.8% vs. 18.0%, P = 0.13) or hospital mortality (28.9% vs. 31.1%, P = 0.44). Although incidence of hypotension was similar (39.7% vs. 41.7%, P = 0.53), patients in the down-titration group more frequently required an escalation of AVP dose (5.7% vs. 11.1%, P < 0.001). Median AVP duration was shorter in the abrupt discontinuation group (1.4 days [IQR: 0.6-2.6 days] vs. 1.8 days [IQR: 1.1-3.2 days], P < 0.001).

CONCLUSIONS

A difference in time to ICU discharge was not detected between abrupt AVP discontinuation and down-titration in patients recovering from septic shock. In patients recovering from septic shock, abrupt discontinuation of AVP appears to be safe and may lead to shortened AVP duration.

Efficacy and Safety of Vasopressin as First-Line Treatment of Distributive and Hemorrhagic Shock States

Background: Norepinephrine remains the first-line option to manage patients with circulatory shock. Limited evidence exists evaluating noncatecholamine compounds as first-line monotherapy for managing noncardiogenic shock. Objective: To compare vasopressin monotherapy with norepinephrine monotherapy for reversal of distributive and hemorrhagic shock. Methods: This was a retrospective cohort study including adult patients who were diagnosed with hypovolemic or septic shock, received fluids, and received norepinephrine or vasopressin monotherapy for at least 1 hour. Patients excluded lacked a clear diagnosis, were initiated on 2 or more vasopressors at once, or underwent cardiac surgery. The primary outcome was time to shock reversal. Secondary outcomes included mortality, lengths of stay, and safety end points. A multivariable Cox proportional hazards model was performed incorporating baseline and treatment variables. Results: A total of 85 and 160 patients were treated with vasopressin and norepinephrine, respectively. A decrease in time to shock reversal was observed in the vasopressin group (58.32 hours [95% CI, 50.88-66.00] vs 74.64 hours [95% CI, 60.96-88.32], P = 0.004). Mortality was lower in the vasopressin group (25% vs 41%, P = 0.01), and intensive care unit length of stay was longer (13 days [interquartile range, IQR = 7-19] vs 7 days [IQR = 5-9], P = 0.006). Remaining secondary outcomes were similar. The multivariable analysis revealed no difference in time to shock reversal. Conclusion and Relevance: First-line vasopressin exhibited faster time to distributive shock reversal in the unadjusted analysis but failed to maintain this difference in the multivariable analysis. These findings support safe use of vasopressin as first-line therapy or as an alternative to norepinephrine in distributive shock.

δ opioid receptor antagonist, ICI 174,864, is suitable for the early treatment of uncontrolled hemorrhagic shock in rats

BACKGROUND

Fluid resuscitation is the essential step for early treatment of traumatic hemorrhagic shock. However, its implementation is greatly limited before hospital or during evacuation. The authors investigated whether δ opioid receptor antagonist ICI 174,864 was suitable for the early treatment of traumatic hemorrhagic shock.

METHODS

With uncontrolled hemorrhagic-shock rats, the antishock effects of six dosages of ICI 174,864 (0.1, 0.3, 0.5, 1, 3, and 5 mg/kg) infused with or without a small volume of lactated Ringer's solution (LR) before bleeding controlled or bleeding cessation at different times were observed.

RESULTS

ICI 174,864 (0.1-3 mg/kg) with or without 1/4 volume of LR infusion showed dose-dependent increase in the mean arterial blood pressure, and significantly prolonged the survival time and 8-h survival rate, as compared with ICI 174,864 plus 1/2 volume of LR infusion. The best effect was shown with 3 mg/kg of ICI 174,864. Bleeding cessation at 1, 2, or 3 h during infusion of ICI 174,864 (3 mg/kg) plus 1/4 volume of LR improved subsequent treatment (70% 24-h survival rate vs. 50 and 10% 24-h survival rate in hypotensive resuscitation and LR group, respectively). There was significant improvement in hemodynamic parameters, oxygen delivery, and tissue perfusion of hemorrhagic-shock rats with 3 mg/kg of ICI 174,864 plus 1/4 volume of LR infusion.

CONCLUSION

δ Opioid receptor antagonist ICI 174,864 alone or with small volume of fluid infusion has good beneficial effect on uncontrolled hemorrhagic shock. Its early application can "buy" time for subsequent treatment of traumatic shock.

A comparison of initial monotherapy with norepinephrine versus vasopressin for resuscitation in septic shock

BACKGROUND

Early goal-directed therapy is a time-sensitive therapeutic algorithm with a tiered approach to target hypoperfusion and cardiovascular collapse within the first 6 hours of septic shock. The Surviving Sepsis Campaign guidelines recommend norepinephrine or dopamine as the initial vasoactive agent for resuscitation in septic shock, reserving the administration of vasopressin as adjunctive therapy.

OBJECTIVE

To determine whether vasopressin was noninferior to norepinephrine as the initial vasopressor to achieve a mean arterial pressure (MAP) goal in the first 6 hours of shock onset.

METHODS

This retrospective cohort study evaluated adults who received monotherapy with either norepinephrine or vasopressin as initial vasoactive therapy for the management of septic shock. Patients were excluded if the treatment arm was not monotherapy, if they were admitted to a cardiology or cardiothoracic surgery service, or if they lacked a comparator-based 1:1 frequency matching.

RESULTS

A total of 130 patients were included, 65 in each treatment arm. The proportion of patients who achieved a goal MAP in the vasopressin group was 63% (95% CI 51%-75%) and was 67.7% (95% CI 56%-79%) in the norepinephrine group. This observed difference between goal MAP attainment did not exceed the predefined noninferiority margin of -25% (CI for 4.7% difference -21.2% to 12%), suggesting noninferiority of vasopressin. No significant difference was identified between vasopressin and norepinephrine for final mean (SD) MAP achieved (75 [9.6] and 76.0 [8.2] mm Hg, respectively; p = 0.06) or the mean total change from baseline MAP to goal (14.1 [8.4] and 15.1 [9.1] mm Hg, respectively; p = 0.6).

CONCLUSIONS

Vasopressin was noninferior to norepinephrine for the achievement of a MAP goal in the first 6 hours from onset of septic shock. Further prospective analysis is warranted; however, the results are useful for consideration of alternative vasopressors in the setting of drug shortages.

Effects of infusion of different fluids during controlled hypotension on gastric intramucosal pH and postoperative gastroenterological function

The present study was aimed to investigate the effects of infusion of different fluids combined with controlled hypotension on gastric intramucosal pH (pHi) and postoperative gastrointestinal function in patients undergoing hepatocarcinoma surgery. Forty-five patients (ASA II) scheduled for surgical resection of hepatocarcinoma undergoing controlled hypotension were randomly assigned to three groups and received infusion of 20 mL/kg Ringer's solution (R group), 6% HAES(H group) or 6% Voluven group (W group). Intragastric PgCO2, pHi, hematocrit and hemoglobin were measured. The significant decrease of pHi and increase of PgCO2 were produced at 1 and 2 h after controlled hypotension in the R group (P < 0.05 or P < 0.01). The time of bowel movement after operation was shorter in the W group than the R group. Meanwhile, we also did not find obvious difference in blood gas indexes among the three groups. The infusion of HAES and Voluven during controlled hypotension could improve gastrointestinal perfusion and accelerate the recovery of postoperative gastrointestinal function.