Phenylephrine Versus Norepinephrine in Spine Surgery: A Prospective Randomized Superiority Comparative Effectiveness Trial (SPiNeS)

The purpose of this research is to compare two commonly used medications, phenylephrine and norepinephrine, that are used to treat low blood pressure during complex spine surgery. The goal is to determine whether one medication better maintains blood flow to the body's organs during surgery and whether it leads to better recovery and fewer complications after surgery.

Study Overview

• Status: Not yet recruiting
• Conditions: Spine Surgery; Tissue Perfusion; Intraoperative Hypotension
• Intervention / Treatment: Drug: Phenylephrine hydrochloride infusion; Drug: Norepinephrine bitartrate infusion

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Mariel Anne Reyes; Phone Number: 904-953-4797; Email: Reyes.Mariel@mayo.edu

Study Locations

• United States
  • Florida
    • Jacksonville, Florida, United States, 32224
      • Mayo Clinic
      • Contact: Mariel Anne Reyes; Phone Number: 904-953-4797; Email: Reyes.Mariel@mayo.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Scheduled for elective complex spine surgery including posterior fusion of 5 or more levels of the thoracic and/or lumbar region.
• ASA physical status classification I-III.
• Able to provide informed consent.

Exclusion Criteria:

• Known allergies or contraindication to NE or PE.
• Pregnant or breastfeeding women.
• Emergency surgeries.
• Persistent atrial fibrillation
• LVEF < 40%
• Moderate or severe valvular dysfunction
• RVSP ≥ 60 mm Hg
• Liver failure or cirrhosis
• eGFR < 15 and/or on hemodialysis
• Minimally invasive or endoscopic surgeries

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Phenylephrine; Participants assigned to this group will undergo elective complex spine surgery with intraoperative blood pressure support managed using phenylephrine as the assigned first-line vasopressor strategy.	Drug: Phenylephrine hydrochloride infusion; Phenylephrine hydrochloride will be prepared at a concentration of 40 mcg/mL and initiated at 0.2 mcg/kg/min. The infusion will be titrated intraoperatively to maintain MAP greater than 85 mmHg from surgical manipulation of vertebrae until final wound closure.
Experimental: Norepinephrine; Participants assigned to this group will undergo elective complex spine surgery with intraoperative blood pressure support managed using norepinephrine as the assigned first-line vasopressor strategy.	Drug: Norepinephrine bitartrate infusion; Norepinephrine bitartrate will be prepared at a concentration of 16 mcg/mL, equivalent to 8.47 mcg/mL norepinephrine base, and initiated at 0.02 mcg/kg/min. The infusion will be titrated intraoperatively to maintain MAP greater than 85 mmHg from surgical manipulation of vertebrae until final wound closure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peak Intraoperative Serum Lactate	Highest intraoperative serum lactate concentration measured during surgery. Serum lactate will be analyzed as a continuous marker of tissue perfusion.	Intraoperatively, from initiation of lactate monitoring through final wound closure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Elevated Intraoperative Serum Lactate	Number of patients with presence of serum lactate greater than 2.0 mmol/L at any time during surgery.	Intraoperatively, from initiation of lactate monitoring through final wound closure
Postoperative Myocardial Injury After Noncardiac Surgery	Presence of postoperative myocardial injury after noncardiac surgery, defined as cardiac troponin greater than the 99th percentile of the upper reference limit and not attributable to a nonischemic cause.	Within 30 days after surgery
Postoperative Acute Kidney Injury	Number of patients to be diagnosed with new acute kidney injury during postoperative hospitalization, based on KDIGO creatinine, urine output, renal replacement therapy, or hemodialysis criteria as specified in the protocol.	During postoperative hospitalization, up to 30 days after surgery
Proportion of Intraoperative Hypotension	Duration of intraoperative MAP less than 85 mmHg divided by total surgical length, expressed as a percentage.	Intraoperatively, from surgical incision to turnover to anesthesia
Volume of Blood Transfusion	Total volume of blood transfusion, stratified by packed red blood cells, fresh frozen plasma, cryoprecipitate, platelets, and cell saver.	During surgery and within 24 hours postoperatively
Length of ICU Stay	Postoperative time during which the participant requires ICU-level care, reported in days.	From ICU admission to discharge from ICU-level care, up to 30 days after surgery
Length of Hospital Stay	Time from anesthesia end until discharge to inpatient rehabilitation, skilled nursing facility, or home, reported in days.	From anesthesia end to hospital discharge, up to 30 days after surgery
Quality of Recovery 15 (QoR-15) Score	QoR-15 is an instrument that uses 15 questions regarding patient support, comfort, emotions, physical independence, and pain. Participants rate each question on a scale of 0 (none of the time) to 10 (all of the time).	14 days post-operatively
30-Day Readmission Rate	Number of patients to be readmitted to the hospital for any reason on or before postoperative day 30.	Within 30 days after surgery
30-Day All-Cause Mortality	Incidence of death from any cause within 30 days of surgery	Within 30 days after surgery

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Investigators: Principal Investigator: Eric Deloso, MD, Mayo Clinic

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): May 1, 2028
• Study Completion (Estimated): May 1, 2028

Study Registration Dates

• First Submitted: August 27, 2026
• First Submitted That Met QC Criteria: August 27, 2026
• First Posted (Actual): September 1, 2026

Study Record Updates

• Last Update Posted (Actual): September 1, 2026
• Last Update Submitted That Met QC Criteria: August 27, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 26-004084

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes