HPI Algorithm for the Prevention of IOH During Spinal Surgery [HPIFPIOH] (HPIFPIOH)

Use of the Hypotension Prediction Index Algorithm (HPI) for the Prevention of Intraoperative Hypotension (IOH) in Adult Patients Undergoing Spinal Surgery: Study Protocol for a Randomized Clinical Trial

The aim of this study is to investigate the hypothesis that the use of the Hypotension Prediction Index algorithm (HPI) can reduce intraoperative hypotension (IOH) in adult patients undergoing spinal surgery in the prone position under general anesthesia, as well as to explore its effect on in-hospital postoperative morbidity and mortality.

Study Overview

• Status: Completed
• Conditions: Intraoperative Hypotension
• Intervention / Treatment: Device: HPI algorithm using Edwards device https://www.edwards.com/gb/devices/decision-software/hpi; Drug: Vasoactive Agent

Detailed Description

The study is a Prospective Randomized clinical trial. Adult patients (>18y) undergoing spinal surgery in the prone position under general anesthesia will be included.

The patients will be randomized using a computer-generated, permuted block randomization with a 1:1 allocation into two groups.

Intervention group: in this group, the HPI algorithm will be used in order to prevent hypotensive episodes Control group: in this group standard anesthetic care will be provided. Hypotensive episodes will be treated with vasoactive agents and fluids.

All patients will receive the same type of anaesthesia (TIVA with propofol) and monitoring including Patient State Index (PSI), non-invasive monitoring of blood pressure, SpO2, continuous electrocardiographic monitoring, ETCO2 and urinary output. Additionally, invasive continuous measurement of the patient's blood pressure will be available via radial artery catheterization. The arterial catheter will be connected to both the standard monitor and the platform which includes the HPI software. Arterial blood gas testing will be performed on an hourly basis.

Intraoperative recordings include PSI values, hemodynamic parameters every 10-15 minutes and urinary output every hour. Hemodynamic parameters will also be collected electronically from the monitor. The total doses of propofol, opioids/sedatives, fluids and vasoactive agents will also be recorded, as well as the estimated blood loss.

In this study, time-weighted average (TWA) in hypotension will be calculated in all patients.[TWA= depth of hypotension x time spent in hypotension / total surgery time].

Postoperatively Blood sampling for hs-TropI will be collected after the surgical procedure and during the following 3 postoperative days. If an increase in the levels hs-Trop I is noted the patient will be inquired for symptoms of myocardial ischemia and a new ECG will be performed. A cardiology consultation will be requested, if necessary.

Creatinine levels and urinary output will be monitored during the first 2 postoperative days. Acute kidney injury will be assessed according to the AKIN classification.

All in-hospital incidents and in-hospital mortality will also be documented.

• Study Type: Interventional
• Enrollment (Actual): 85
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Greece
  • Athens, Greece
    • Attikon Hospital
  • Attiki
    • Athens, Attiki, Greece, 11527
      • General Hospital of Athens "Georgios Gennimatas"

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 86 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients undergoing scheduled spine surgery performed in prone position under general anaesthesia

Exclusion Criteria:

• Heart failure with reduced ejection fraction (LVEF<35%)
• Severe aortic and/or mitral regurgitation
• Persistent atrial fibrillation or other significant cardiac arrhythmias
• Significant preoperative hypotension
• End-stage renal disease on dialysis/RRT

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Intervention group: The HPI algorithm will be used in order to prevent hypotensive episodes. When the HPI is greater than 85%, the anesthesiologist will have to intervene within the next 2 minutes taking the hemodynamic parameters available into consideration, as well as the treatment protocol that has been designed according to current literature	Device: HPI algorithm using Edwards device https://www.edwards.com/gb/devices/decision-software/hpi; The HPI algorithm will be used in order to prevent hypotensive episodes. When the HPI is greater than 85%, the anesthesiologist will have to intervene within the next 2 minutes taking the hemodynamic parameters available into consideration, as well as the treatment protocol that has been designed according to current literature; Other Names: noradrenaline; phenylephrine; Drug: Vasoactive Agent; Hypotensive episodes will be treated with vasoactive agents and fluids. The HPI algorithm recordings will be blinded and will not be available to the anesthesiologist for the duration of the operation.; Other Names: noradrenaline; phenylephrine
Other: Control group: Hypotensive episodes will be treated with vasoactive agents and fluids according to the standard clinical practice. The HPI algorithm recordings will be blinded and will not be available to the anesthesiologist for the duration of the operation.	Drug: Vasoactive Agent; Hypotensive episodes will be treated with vasoactive agents and fluids. The HPI algorithm recordings will be blinded and will not be available to the anesthesiologist for the duration of the operation.; Other Names: noradrenaline; phenylephrine

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time-weighted average (TWA) in hypotension	Time-weighted average (TWA) in hypotension will be calculated in all patients.	Up to 15 minutes after the end of operation

Collaborators and Investigators

• Sponsor: Attikon Hospital
• Investigators: Principal Investigator: Paraskevi Matsota, Prof, 2nd Department of Anesthesiology, Attikon University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): May 11, 2022
• Primary Completion (Actual): November 4, 2023
• Study Completion (Actual): October 10, 2024

Study Registration Dates

• First Submitted: April 17, 2022
• First Submitted That Met QC Criteria: April 17, 2022
• First Posted (Actual): April 22, 2022

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 15, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypotension; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Neurotransmitter Agents; Protective Agents; Adrenergic alpha-Agonists; Adrenergic Agonists; Adrenergic Agents; Respiratory System Agents; Cardiotonic Agents; Sympathomimetics; Vasoconstrictor Agents; Mydriatics; Nasal Decongestants; Adrenergic alpha-1 Receptor Agonists; Norepinephrine; Oxymetazoline; Phenylephrine
• Other Study ID Numbers: HPIFPIOH

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