no funding for the study

The purpose of the present study is to evaluate the effect of vasopressin compared to norepinephrine on the clinical complications of patients with vasospastic shock after noncardiac surgeries.

The Systemic Inflammatory Response Syndrome (SIRS) is a common complication after non-cardiac surgery, impacting negatively on patient outcome and with high incidence rates. Vasoplegic syndrome is the most serious complication of SIRS and can happen after any type of surgery. The etiology of the vasoplegic syndrome has not yet been fully elucidated, but is known to occur more frequently in patients at high surgical risk, submitted to major surgeries, or in the presence of perioperative complications and patients with comorbidities. In this circumstance, the depletion of vasopressin stocks is described, which may contribute to the refractoriness of the shock and the lack of response to the catecholaminergic drugs. The standard treatment of perioperative vasoplegia has been adequate volume replacement and administration of vasopressors, with norepinephrine being the most commonly used. However, it is known that norepinephrine may have deleterious effects on the body and in 20% of patients with vasospastic shock it is ineffective. Previous studies have suggested benefits of adding vasopressin in refractory situations, especially in septic shock. Recently the VANCS study (Vasopressin or norepinephrine in the vasopregic shock after cardiac surgery: double-blind, controlled and randomized study) demonstrated superiority of vasopressin in the reversion of vasoplegic shock after cardiac surgery, as well as a lower incidence of renal insufficiency, atrial fibrillation and shorter hospitalization time. (Anesthesiology. 2017 Jan;126(1):85-93.)

Inclusion Criteria:

• Age greater than 18 years;
• Patients undergoing high-risk non-cardiac surgery;
• vasopressor need within 24 hours after surgery, defined as mean arterial pressure (MAP) <65 mmHg after volume resuscitation with at least 1 liter of crystalloid solution (Ringer's lactate) and maintaining a cardiac index> 2.2 ml / min / m²;
• Signature of the informed consent form.

Exclusion Criteria:

• Allergy to vasoactive drugs;
• Previous use of vasopressor;
• Gestation;
• Presence of Raynaud's phenomenon, altered Allen's test, systemic sclerosis or vasospastic diathesis;
• Severe hyponatremia (Na <130 mEq / L);
• Acute mesenteric ischemia;
• Acute coronary syndrome;
• Participation in another study;
• Refusal to participate in the study.