Vasopressin – what it does and doesn’t do

The current Surviving Sepsis campaign guidelines recommend that vasopressin should not be administered as the initial vasopressor in septic shock, and that vasopressin at constant dosage of 0.03 units/min may be added to norepinephrine with anticipation of an effect equivalent to that of norepinephrine alone. European intensivists conducted a systematic review to determine vasopressin’s risks and benefits in vasodilatory shock. There was no demonstrated survival benefit but its use is associated with a significant reduction in norepinephrine requirement.

Interestingly, the authors point out: ‘Low-dose vasopressin may help to restore blood pressure in patients with hypotension refractory to catecholamines, and may favor pulmonary vasodilation and increase glomerular filtration rate and plasma cortisol levels’.

My take home: consider its use if an apparent vasodilatory shock state is refractory to catecholamines, but don’t stress if you don’t have access to it (or it will complicate practical aspects of organising resuscitation and transfer), since there’s still no clear evidence for outcome benefit.



OBJECTIVE:
To examine the benefits and risks of vasopressin or its analog terlipressin for patients with vasodilatory shock.


DATA SOURCE:
We searched the CENTRAL, MEDLINE, EMBASE, and LILACS databases (up to March 2011) as well as reference lists of articles and proceedings of major meetings; we also contacted trial authors. We considered randomized and quasirandomized trials of vasopressin or terlipressin versus placebo or supportive treatment in adult and pediatric patients with vasodilatory shock. The primary outcome for this review was short-term all-cause mortality.


STUDY SELECTION:
We identified 10 randomized trials (1,134 patients). Six studies were considered for the main analysis on mortality in adults.


DATA EXTRACTION AND SYNTHESIS:
The crude short-term mortality was 206 of 512 (40.2%) in vasopressin/terlipressin-treated patients and 198 of 461 (42.9%) in controls [six trials, risk ratio (RR) = 0.91; 95% confidence interval (CI) 0.79-1.05; P = 0.21; I (2) = 0%]. There were 49 of 463 (10.6%) patients with serious adverse events in the vasopressin/terlipressin arm and 51 of 431 (11.8%) in the control arm (four trials, RR = 0.90; 95% CI 0.49-1.67; P = 0.75; I (2) = 26%). Metaregression analysis showed negative correlation between vasopressin dose and norepinephrine dose (P = 0.03).


CONCLUSIONS:
Overall, use of vasopressin or terlipressin did not produce any survival benefit in the short term in patients with vasodilatory shock. Physicians may value the sparing effects of vasopressin/terlipressin on norepinephrine requirement given its apparent safe profile.


Vasopressin for treatment of vasodilatory shock: an ESICM systematic review and meta-analysis
Intensive Care Med. 2012 Jan;38(1):9-19