The Hypotension Prediction Index in Free Flap Transplant in Head and Neck Surgery.

Study Overview
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Brief Summary
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The aim of the current study is to evaluate the effects of the Hypotension Prediction Index (HPI) on the degree of intraoperative hypotension in patients undergoing free flap surgery. The hypothesis is that implementation of the HPI algorithm will reduce the time-weighted average (TWA) intraoperative hypotension below a threshold of 65 mmHg (16), and to reveal the relationship between the episodes of hypotension and free flap viability and function.

Official Title
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The Hypotension Prediction Index in Free Flap Transplant in Head and Neck Surgery - a Pilot Study.

Conditions
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Hypotension, Head and Neck Cancer, Perioperative Complication, Postoperative Complications

Intervention / Treatment
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* Device: Hypotension Prediction Index


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients qualified to head and neck free flap surgery Written informed consent Exclusion Criteria: Patients under 18 years Lack of health insurance Pregnancy Known history of congenital heart disease, severe aortic and/or mitral stenosis, heart failure and ejection fraction < 35 % Persistent atrial fibrillation and other arrhythmias impairing arterial pressure-based cardiac output (APCO) monitoring

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: This prospective, randomized, controlled clinical trial will be performed in Poznan University of Medical Science Hospital. Patients fulfilling the inclusion criteria (see below) will be randomly assigned to receive invasive blood pressure monitoring + standard medical therapy (group A) or the hemodynamic monitoring with the Hypotension Prediction Index software (group B).
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Standard Therapy Group<br>The standard therapy group patients will have invasive blood pressure monitoring + standard medical therapy. The therapeutic decision regarding treatment of hypotension, the use of fluids and vasopressors will be determined by the anaesthesia team. The decisions will be based on the information from the standard invasive blood pressure monitoring. | |
| Experimental: Hypotension Prediction Index Group<br>The HPI-group will have the HPI based monitoring with the Acumen IQ sensor (Edwards Lifesciences) and the HPI algorithm connected also to the HemoSphere platform (Edwards Lifesciences). The hemodynamic management will be based on the HPI indications and the specific algorithm, which considers hypovolemia, impaired contractility and vasodilatation. An alert pops up on the monitor screen when the HPI values exceeds 85 and then the clinician needs to make therapeutic decision in order to avoid the hypotensive episode. | Device: Hypotension Prediction Index<br>* Hemodynamic perioperative monitoring with the Hypotension Prediction Index<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TWA Mean Arterial Pressure (MAP) < 65 mmHg | TWA - MAP < 65 mmHg - time weighed average = (depth of hypotension in millimeters of mercury below a MAP of 65 mmHg x time in minutes spent below MAP of 65mmHg)/total duration of operation in minutes | From the beginning of the anesthesia to the end of anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TWA - MAP < 60 mmHg | time weighed average = (depth of hypotension in millimeters of mercury below a MAP of 60 mmHg x time in minutes spent below MAP of 60 mmHg)/total duration of operation in minutes | From the beginning of the anesthesia to the end of anesthesia | 
| TWA - MAP < 55 mmHg | time weighed average = (depth of hypotension in millimeters of mercury below a MAP of 55 mmHg x time in minutes spent below MAP of 55 mmHg)/total duration of operation in minutes | From the beginning of the anesthesia to the end of anesthesia | 
| 30 day mortality | 30 day mortality | 30 days | 
| Length of hospitalisation | Length of hospitalisation | From date of randomisation to the date of hospital discharge or date of death, whichever came first, assesed up to 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypotension, Hypotension Prediction Index, Free Flap Transplant, Head and Neck Cancer, Perioperative Complications