Vasopressor Outcomes in Spine Surgery

Study Overview
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Brief Summary
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This is a prospective, randomized control trial comparing norepinephrine versus phenylephrine for vasopressor support in patients undergoing elective spinal fusion surgery.

Detailed Description
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There is limited evidence on the difference in postoperative outcomes between the choices of vasopressors used to treat intraoperative hypotension (IOH) in patients undergoing non-cardiac surgery under general anesthesia. A recent pilot feasibility trial comparing norepinephrine and phenylephrine for first-line intravenous infusion of vasopressor during general anesthesia and major non-cardiac surgery was unable to show any difference in postoperative outcomes. Although the study demonstrated safety and feasibility, it was not powered to detect differences in postoperative outcomes. The impact of vasopressors on postoperative outcomes in patients undergoing complex spinal surgery in the prone position is even scarcer. While it has been demonstrated that the use of intra-operative vasopressor infusion is safe and well tolerated, without any adverse renal outcomes, it is unclear if the choice of vasopressor makes any difference. While animal studies have shown that norepinephrine may provide greater spinal cord protection than phenylephrine, clinical studies in humans are lacking. We aim to fill this gap in knowledge by carrying out a prospective, randomized control trial to evaluate differential outcomes related to the choice of norepinephrine versus phenylephrine as the preferential vasopressor in patients undergoing elective spinal fusion surgery in the prone position.

Official Title
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Vasopressor Outcomes in Spine Surgery

Conditions
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Hypotension

Intervention / Treatment
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* Drug: Phenylephrine
* Drug: Norepinephrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: -Patients > 18 years undergoing elective, prone, spinal fusion surgery Exclusion Criteria: Age < 18 years Emergency surgery Outpatient surgery Pregnancy End-stage renal disease requiring dialysis Diagnosed myocardial ischemia and/or cardiac revascularization within the past month

Ages Eligible for Study
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Minimum Age: 18 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Phenylephrine<br>Patients receiving phenylephrine for intraoperative hypotension | Drug: Phenylephrine<br>* Intraoperative phenylephrine infusion Phenylephrine infusion to be titrated as needed to target a mean arterial pressure (MAP) > 65 mm Hg.<br>|
| Active Comparator: Norepinephrine<br>Patients receiving norepinephrine for intraoperative hypotension | Drug: Norepinephrine<br>* Intraoperative norepinephrine infusion Norepinephrine infusion to be titrated as needed to target a MAP > 65 mm Hg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vasopressor requirement | Total intraoperative vasopressor requirement | During inpatient admission | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative acute kidney injury | Kidney Disease Improving Global Outcomes (KDIGO) criteria Acute Kidney Injury (AKI) is defined as any of the following: Increase in serum creatinine (sCr) ≥0.3 mg/dL (≥26.5 μmol/L) within 48 hours; or Increase in sCr ≥1.5 times baseline, which is known or presumed to have occurred within the prior 7 days; or Urine volume <0.5 mL/kg/h for 6 hours | During inpatient admission | 
| Intraoperative transfusion requirement |  | During inpatient admission | 
| Postoperative vasopressor requirement |  | During inpatient admission | 
| Length of ICU stay |  | During inpatient admission | 
| Length of hospital stay |  | From admission to discharge (up to 100 weeks) | 
| 30-day readmission |  | 30-days post-discharge | 
| Postoperative Myocardial Injury | Troponin elevation (ng/L) | During inpatient admission | 
| Postoperative Lactate Elevation | Lactate (mmol/L) | During inpatient admission | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vasopressor, Phenylephrine, Norepinephrine, Spine Surgery, General Anesthesia