Post Anaesthesia Care Hypotension Prevention

Study Overview
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Brief Summary
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The goal of this clinical trial is to investigate if the use of the hypotension prediction index during the perioperative period leads to a decrease in hypotension both during and after surgery (24 hrs) in adults undergoing major abdominal surgery. The main question this trial aims to answer is: • Does the use of the hypertension prediction index (HPI) decrease hypotension during surgery and in the post-operative period? During and after their surgery, participants in the intervention group will be treated according to the HPI-algorithm. Participants in the control group will be treated following the standard of care.

Detailed Description
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Rationale: Hypotension during and after surgery is associated with serious complications. Using a machine learning algorithm, hypotension can be accurately predicted. Edwards Lifesciences developed this algorithm, called Hypotension Prediction Index and integrated this in their hemodynamical monitors. Recent studies have shown a decrease in intraoperative hypotension when using the hypotension prediction index. Objective: To investigate if the use of the hypotension prediction index during the perioperative period leads to a decrease in hypotension (time weighted average) both during and after surgery (24 hrs). Intervention: Patients in the intervention group will be treated using the hypotension prediction index algorithm to prevent hypotension. In case of actual hypotension the treatment thereof is at the discretion of the anaesthesiologist. Main study parameters/endpoints: The decrease in time weighted average of hypotension in the peri- and post-operative period.

Official Title
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The Clinical Effects of Perioperative Use of the Hypotension Prediction Index

Conditions
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Hypotension During Surgery

Intervention / Treatment
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* Device: HPI (using HemoSphere) - guided algorithm
* Device: Treatment of hypotension following standard of care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients > 18 years old Patients planned to undergo laparotomy surgery Patients that will receive an invasive arterial catheter as part of their procedure Patients that are planned to go to the post anaesthetic care unit (PACU) post-operatively Exclusion Criteria: Patients with known arrythmias Patients with known severe heart valve disease Patients with the need for dialysis Clamping of the aorta or Pringle's manoeuvre during surgery Emergency procedures

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: 1 control group, 1 intervention group without cross-over
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HPI-intervention algorithm<br>In the intervention group the HemoSphere screen is visible and the anesthesiologist and PACU personal are instructed to follow the algorithm (chapter 4) in case of a HPI >85%. The purpose of the alarm at 85% and the presented algorithm is to prevent hypotension. If hypotension occurs, it should be treated as according to the standard of care. | Device: HPI (using HemoSphere) - guided algorithm<br>* Treatment of hypotension guided by the hypotension prediction index. Patients will receive treatment following the predetermined HPI-algorithm when the HPI exceeds 85%.<br>|
| Other: Control group<br>Patients in the control group are connected to the HemoSphere monitor to evaluate the TWA of hypotension in this group. The screen is not visible to the anesthesiologist or PACU personal and the alarm is set silent. It will be explained to the anesthesiologist and PACU personal that the patients are included to this study and that a blood pressure with a MAP of 65 mmHg should be monitored. | Device: Treatment of hypotension following standard of care<br>* Patients receive standard of care treatment for hypotension, with a goal-mean arterial pressure (MAP) of 65mmHg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time Weighted Average of hypotension | Time Weighted Average (TWA) is measured as (depth of hypotension in mmHg below a MAP op 65mmHg x time in minutes spent below a MAP of 65mmHg) ÷ total duration of surgery/PACU admission in minutes) | During the accumulative duration of surgery and PACU admission | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Frequency and duration of hypotension | Defined as MAP<65mmHg for at least 1 minute | During surgery and in the 24 hours following surgery | 
| Frequency and duration of hypertension | Defined as MAP>100mmHg for at least 1 minute | During surgery and in the 24 hours following surgery | 
| Total amount of administered fluids | Total amount of administered fluids (absolute, ml/kg/min, input/output ratio) | During surgery and in the 24 hours following surgery | 
| Total administration of vasopressors | Total administration of vasopressors (mcg/kg/min) | During surgery and in the 24 hours following surgery | 
| Total administration of inotropy | Total administration of inotropy (mcg/kg/min) | During surgery and in the 24 hours following surgery | 
| Eligibility for discharge to the ward on the day after surgery | Eligibility defined as yes or no | During morning rounds the day after surgery (approximately at 10.00hours) | 
| Lactate | Lactate level as measured in arterial blood gas | at the start of surgery, at PACU admission, day after surgery at 06.00hours | 
| Glomerular filtration rate | Glomerular filtration rate as measured in arterial blood gas | at the start of surgery, at PACU admission, day after surgery at 06.00hours | 
| Number and type of complications in the first 30 days after surgery | Number and type of complications in the first 30 days after surgery | 30 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Laparotomy, Hypotension, Goal Directed Therapy, Post-operative, Prediction, Artificial intelligence