Lack of an effect of body mass on the hemodynamic response to arginine vasopressin during septic shock
ABSTRACT To determine whether body mass alters the effectiveness of a fixed-dose infusion of arginine vasopressin.
Retrospective medical record review.
All intensive care units of a tertiary medical center.
Sixty-six mechanically ventilated patients who received a fixed-dose intravenous infusion of arginine vasopressin at 0.04 U/minute as the sole agent for hemodynamic support during septic shock.
Patients were divided into four groups on the basis of body mass index. Effectiveness was measured as hemodynamic stability, which was defined as the proportion of patients achieving a mean arterial pressure (MAP) of 65 mm Hg or higher, the magnitude of the change in MAP at 1 hour, and the need for additional rescue vasopressors. Secondary outcomes included mortality and length of stay. Baseline characteristics of all four groups were comparable for age, sex, and severity of illness determined by using Acute Physiology and Chronic Health Evaluation II (APACHE II), Simplified Acute Physiology II (SAPS II), and Sequential Organ Failure Assessment (SOFA) scores. The only significant differences in baseline characteristics among the groups were in their central venous pressures. The four groups similarly achieved hemodynamic stability at 1 hour after the administration of arginine vasopressin (p=0.41). We observed no significant differences among groups in the magnitude of MAP change (p=0.62), need for rescue catecholamine vasopressors (p=0.17), 28-day mortality rates (p=0.31), or length of stay in the intensive care unit (p=0.43).
Body mass index did not alter the effects of arginine vasopressin on hemodynamic stability or changes in MAP when the drug was administered as a fixed-dose infusion of 0.04 U/minute. Our results do not support weight-based dosing of vasopressin, unlike the dosing for catecholamine vasopressors.
[Show abstract] [Hide abstract]
ABSTRACT: Vasopressors used for the management of septic shock are often dosed according to body weight. Use of vasopressin for physiologic replacement in patients with septic shock is usually administered as a standard non-weight-based dose. We hypothesized that the efficacy of vasopressin may be influenced by body weight. The primary objective was to determine if the effects of vasopressin on other vasopressor dosing requirements is related to body weight. Secondary objectives included evaluation of blood pressure and heart rate after the start of vasopressin infusion. A retrospective, cohort study in a large academic health center was conducted. Sixty-four adult inpatients with septic shock (26 medical intensive care unit and 38 surgical intensive care unit) who required vasopressor administration including vasopressin therapy were included. Dosing requirements of vasopressors were captured 1 hour before and during the hour of vasopressin initiation and 2 and 4 hours later. Other information collected during the study period included blood pressure, mean arterial pressure, and heart rate. Most of the patients (n = 61) received vasopressin at a dose of 0.04 U/min. Changes in vasopressor dosing were significantly correlated with weight-adjusted vasopressin at 2 hours (correlation coefficient = -0.36, P = .03) and 4 hours (correlation coefficient = -0.46, P < .001). Use of vasopressin was associated with significant increases in systolic blood pressure, diastolic blood pressure, and mean arterial pressure at each time point compared with baseline. Effects of vasopressin on catecholamine dosing requirements in the setting of septic shock may be influenced by body weight. Prospective studies are needed to examine weight-based dosing of vasopressin in this setting.Journal of critical care 08/2011; 27(3):289-93. DOI:10.1016/j.jcrc.2011.06.018 · 2.19 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: STUDY OBJECTIVES: To determine whether vasopressin is detectable in the continuous venovenous hemodialysis (CVVHD) effluent of patients receiving exogenous arginine vasopressin, and to determine whether treatment-specific factors are associated with vasopressin levels in CVVHD effluent. DESIGN. Prospective observational study. SETTING. Intensive care units of a tertiary care academic medical center. PATIENTS. Twenty-seven adults with vasodilatory shock who received a stable-dose continuous intravenous infusion of arginine vasopressin with concomitant uninterrupted CVVHD for at least 4 hours between September 2008 and May 2010. MEASUREMENTS AND MAIN RESULTS. Vasopressin levels in CVVHD effluent were assessed by radioimmunoassay. Statistical analysis was performed with analysis of variance and Pearson correlation. A multivariate linear regression was used to assess for independent factors associated with vasopressin levels in CVVHD effluent. The CVVHD effluent of all patients was assessed for vasopressin levels. The median exogenous arginine vasopressin dose was 0.03 unit/minute (range 0.02-0.18 unit/min), whereas the median CVVHD effluent flow rate was 22.6 ml/kg/hour (interquartile range [IQR] 21.5-26.8 ml/kg/hr). Vasopressin was detectable in all effluent samples (median 88.8 pg/ml, IQR 36.4-113.7 pg/ml). There were no significant differences in CVVHD effluent vasopressin levels among CVVHD filter types (p=0.39). The CVVHD effluent vasopressin levels correlated with exogenous arginine vasopressin dose (r2=0.49, p<0.001). After adjustment for CVVHD effluent flow rate and administration of corticosteroids, with multivariate linear regression, only exogenous arginine vasopressin dose was independently associated with CVVHD effluent vasopressin level. CONCLUSION. Vasopressin is detectable in CVVHD effluent, suggesting that it is removed by CVVHD. In addition, exogenous arginine vasopressin infusion dose is independently associated with CVVHD effluent vasopressin level.Pharmacotherapy 09/2011; 31(9):857-62. DOI:10.1592/phco.31.9.857 · 2.20 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Sepsis remains one of the leading causes of mortality in the United States. Cardiovascular compromise is one of the major contributors to the high mortality associated with sepsis. Current cardiovascular support in patients with septic shock involves fluid administration, use of catecholamines, and potentially the use of inotropes, corticosteroids, or arginine vasopressin. Vasopressin is an endogenous hormone essential for both osmotic and cardiovascular homeostasis. Various studies have suggested that exogenous administration of arginine vasopressin may be an effective adjunctive therapy to traditional catecholamines for the management of hypotension during septic shock. Of particular interest is the Vasopressin and Septic Shock Trial (VASST), which found no mortality benefit when comparing the addition of arginine vasopressin to norepinephrine versus continuous dose increases in norepinephrine alone. However, results of the a priori subgroup and post hoc analyses of this trial suggest that patients may benefit if arginine vasopressin is used in patients with less severe shock, defined as those receiving a relatively low norepinephrine-equivalent dose of 5-14 μg/minute, or in those at risk for renal failure. Current guidelines from the Surviving Sepsis Campaign recommend arginine vasopressin 0.03 unit/minute may be added to norepinephrine with the anticipation of an effect equal to higher doses of norepinephrine alone. Many practitioners continue to utilize arginine vasopressin for patients with septic shock due to its mechanisms of benefit on pathophysiologic derangements in this disease. Clinicians must be knowledgeable about the use of arginine vasopressin in septic shock, including controversial areas where guidelines do not always provide concrete recommendations.Pharmacotherapy 10/2010; 30(10):1057-71. DOI:10.1592/phco.30.10.1057 · 2.20 Impact Factor