5 Versus 10 mcg Norepinephrine Bolus in Treatment of Postinduction and Early Intraoperative Hypotension in Emergency Abdominal Surgery

Comparing 5 mcg and 10 mcg Norepinephrine Bolus in Treatment of Postinduction and Early Intraoperative Hypotension in Emergency Abdominal Surgery: a Randomized Controlled Trial

Postinduction hypotension is a frequent intraoperative complication, particularly in emergency abdominal surgery due to factors such as sepsis, hypovolemia, and limited preoperative cardiac assessment. Because it can lead to serious organ injury, prompt prevention and management are essential. Vasopressors, including ephedrine, phenylephrine, and norepinephrine, are commonly used, with NE gaining interest as an intraoperative bolus despite uncertainty about the optimal dose in general surgery population The aim of this study is to compare 5 mcg to 10 mcg norepinephrine bolus for treatment of postinduction hypotension and early intraoperative in emergency abdominal surgery.

Study Overview

• Status: Not yet recruiting
• Conditions: Hypotension on Induction; Emergency Surgery; Norepinephrine
• Intervention / Treatment: Drug: Norepinephrine 5 mcg; Drug: Norepinephrine 10 mcg

Detailed Description

fluid assessment using stroke volume change after passive leg raising maneuver will be applied. If stroke volume increase >10%, 500-mL bolus of lactated ringer will be given. Passive leg raising will be repeated until the patient is non-responder or 1500 mL were infused.

intraoperatively, heart rate and blood pressure will be monitored at 2 min intervals until 30 min after skin incision.

• Study Type: Interventional
• Enrollment (Estimated): 136
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Maha Mostafa, MD; Phone Number: +201000365115; Email: maha.mostafa@cu.edu.eg

Study Locations

• Egypt
  • Cairo Governorate
    • Cairo, Cairo Governorate, Egypt
      • Cairo University

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adult patients, American Society of anesthesiologists (ASA) I-III undergoing emergency abdominal surgery

Exclusion Criteria:

• Severe cardiac morbidities (impaired contractility with ejection fraction < 45%, heart block, arrhythmias, tight valvular lesions)
• Patients on vasopressor infusion,
• Pregnant or lactating women,
• Allergy of any of the study drugs

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Norepinephrine 5-mcg group; The study drug will be prepared by diluting 4000 mcg of NE in 400 mL of normal saline to achieve a concentration of 10 mcg/mL. The assigned dose (5 mcg, 0.5 mL of the prepared solution) will then be further diluted with normal saline in a 10-mL syringe.	Drug: Norepinephrine 5 mcg; Norepinephrine dose of 5 mcg will be given if patient developed hypotension (mean arterial pressure <65 mmHg). The norepinephrine bolus (5 mcg) will be repeated if mean arterial pressure is not restored within 2 min. Norepinephrine infusion will be started if hypotension persisted after three boluses.
Active Comparator: Norepinephrine 10-mcg group; The study drug will be prepared by diluting 4000 mcg of NE in 400 mL of normal saline to achieve a concentration of 10 mcg/mL. The assigned dose (10 mcg, 1 mL of the prepared solution) will then be further diluted with normal saline in a 10-mL syringe.	Drug: Norepinephrine 10 mcg; Norepinephrine dose of 10 mcg will be given if patient developed hypotension (mean arterial pressure <65 mmHg). The norepinephrine bolus (10 mcg) will be repeated if mean arterial pressure is not restored within 2 min. Norepinephrine infusion will be started if hypotension persisted after three boluses.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of successfully managed hypotensive episode	mean arterial pressure >65 mmHg within 2 min of drug administration	from 0 min of induction of anesthesia until 30 min after skin incision

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area under a mean arterial pressure of 65 mmHg	The area under a mean arterial pressure (MAP) of 65 mm Hg will be calculated by subtracting MAP measurements from 65 mm Hg, multiplying positive differences with the time difference (in minutes) between this MAP measurement and the consecutive MAP measurement, and summing the values	from 0 min of induction of anesthesia until 30 min after skin incision
Duration of MAP<65 mmHg	in minutes	from 0 min after induction of anesthesia until 30 min after skin incision
bradycardia	heart rate < 50 bpm following drug administration	from 0 min after induction of anesthesia until 30 min after skin incision
hypertension	systolic blood pressure >120% of baseline following drug administration	from 0 min after induction of anesthesia until 30 min after skin incision

Collaborators and Investigators

• Sponsor: Cairo University

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: July 17, 2026
• First Submitted That Met QC Criteria: July 17, 2026
• First Posted (Actual): July 22, 2026

Study Record Updates

• Last Update Posted (Actual): July 22, 2026
• Last Update Submitted That Met QC Criteria: July 17, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: norepinephrine; hypotension; emergency surgery
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypotension; Organic Chemicals; Hydrocarbons; Hydrocarbons, Cyclic; Hydrocarbons, Aromatic; Amines; Catechols; Phenols; Benzene Derivatives; Alcohols; Amino Alcohols; Ethanolamines; Biogenic Monoamines; Biogenic Amines; Catecholamines; Norepinephrine
• Other Study ID Numbers: MS-303-2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: data related to this research is available form the PI upon reasonable request

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No