Prediction of Hemodynamic Instability in Patients Undergoing Surgery

Study Overview
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Brief Summary
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Intraoperative hypotension occurs often and is associated with adverse patient outcomes such as stroke, myocardial infarction and renal injury. The aim of this study was to test the accuracy of a physiology-based machine-learning algorithm using continuous non-invasive measurement of the blood pressure waveform with the Nexfin® finger cuff during surgery.

Official Title
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Prediction of Hemodynamic Instability in Patients Undergoing Surgery

Conditions
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Blood Pressure, Prediction Models, Machine Learning, Hemodynamic Instability

Intervention / Treatment
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* Diagnostic Test: Hypotension Probability Indicator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: all adult patients undergoing surgery Exclusion Criteria: none

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Hypotension Probability Indicator|The accurary of the Hypotension Probability Indicator (HPI) is tested in the created offline database. This means data was prospectively collected but the HPI algorithm was not tested prospectively but after collection in the offline database.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity of the HPI algorithm | Sensitivity | three minutes prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | three minutes prior to the hypotensive event | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Predictive positive value of the HPI algorithm | Predictive positive value | one minute prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | two minutes prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | three minutes prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | four minutes prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | five minutes prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | ten minutes prior to the hypotensive event | 
| Predictive positive value of the HPI algorithm | Predictive positive value | 15 minutes prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | one minute prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | two minutes prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | four minutes prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | five minutes prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | ten minutes prior to the hypotensive event | 
| Negative predictive value of the HPI algorithm | Negative predictive value | 15 minutes prior to the hypotensive event | 
| Time from HPI alarm to hypotensive event during surgery | Time from HPI alarm to hypotensive event, this can range from 0,1 min to a high number such as 30 or even 40 minutes. | From the onset of the HPI alarm to the hypotensive event during surgery, this is in minutes. (this can range from 0,1 min to a high number such as 30 or even 40 minutes) | 
| Sensitivity of the HPI algorithm | Sensitivity | one minute prior to the hypotensive event | 
| Sensitivity of the HPI algorithm | Sensitivity | two minutes prior to the hypotensive event | 
| Sensitivity of the HPI algorithm | Sensitivity | five minutes prior to the hypotensive event | 
| Sensitivity of the HPI algorithm | Sensitivity | ten minutes prior to the hypotensive event | 
| Sensitivity of the HPI algorithm | Sensitivity | 15 minutes prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | one minute prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | two minutes prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | five minutes prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | ten minutes prior to the hypotensive event | 
| Specifity of the HPI algorithm | Specifity | 15 minutes prior to the hypotensive event |