Small Doses of Pituitrin Versus Norepinephrine for the Management of Vasoplegic Syndrome in Patients After Cardiac Surgery

Study Overview
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Brief Summary
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Vasoplegic syndrome is a common complication after cardiac surgery. Low dose vasopressin can up-regulate blood pressure and improve clinical outcomes compared with norepinephrine (mainly acute kidney injury Anesthesiology 2017; 126:85-93). Pituitrin is used as a substitute for vasopressin in our center, which contains both vasopressin and oxytocin. Oxytocin may alleviate inflammatory process-associated kidney injury (Peptides 2006;27:2249-57). Therefore, the investigators hypothesize Pituitrin may be preferable to norepinephrine in the renal protection of patients with vasoplegic syndrome after cardiac surgery. Moreover, the serum levels of vasopressin, catecholamine, corticosteroid and corticotropin-releasing hormone will be measured.

Official Title
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Small Doses of Pituitrin Versus Norepinephrine for the Management of Vasoplegic Syndrome in Patients After Cardiac Surgery

Conditions
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Postoperative Vasoplegic Syndrome

Intervention / Treatment
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* Drug: Pituitrin infusion
* Drug: Norepinephrine infusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Patients diagnosed as vasoplegic syndrome(defined as mean arterial pressure less than 65 mmHg resistant to fluid challenge and cardiac index greater than 2.2 L/min · m2) within 24 hours after cardiac surgery. Exclusion Criteria: Age < 18 and > 75 years. Received renal replacement therapy before cardiac surgery. Diagnosed as endocrine disease before cardiac surgery. Diagnosed as sever peripheral vascular disease before cardiac surgery. Extracorporeal membrane oxygenation support before admission. To receive heart transplantation. Infection on admission. Pregnant or maternal patients. Refusal of consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Pituitrin arm<br>To begin with 0.02 U/min to maintain mean arterial pressure(MAP) higher than 65 mmHg. | Drug: Pituitrin infusion<br>* To begin with 0.02 U/min to maintain mean arterial pressure(MAP) higher than 65 mmHg.<br>|
| Experimental: Norepinephrine arm<br>To begin with 0.04 μg/kg.min to maintain mean arterial pressure(MAP) higher than 65 mmHg. | Drug: Norepinephrine infusion<br>* To begin with 0.04 μg/kg.min to maintain mean arterial pressure(MAP) higher than 65 mmHg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of in-hospital acute renal injury | Acute renal injury (AKI) is defined as any of the following: (1) increase in serum creatinine (SCr) by ≥ 26.5lmol/l in 48 hours; (2) increase in SCr to ≥ 1.5 times baseline, which is known or presumed to have occurred within the prior 7 days; or (3) urine output < 0.5 ml/kg/h for 6 hours (urine output is only assessed when the CRRT machine is absent or with a fluid removal rate of 0 ml/h). | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| In-hospital mortality | All-cause mortality | 30 days | 
| Rate of new arrhythmias | Rate of new arrhythmias after cardiac surgery | 30 days | 
| Hormone levels | Serum hormone levels after cardiac surgery, including vasopressin, catecholamine, corticosteroid and corticotropin-releasing hormone | 30 days | 
| Rate of ECMO or LVAD support | Receiving extracorporeal membrane oxygenation (ECMO) or left ventricle assist device (LVAD) support | 30 days | 
| Duration on ventilator support | Duration on ventilator support after cardiac surgery | 30 days | 
| ICU length of stay | ICU length of stay | 30 days | 
| Hospital length of stay after cardiac surgery | Hospital length of stay after cardiac surgery | 30 days |