Ankle/Brachial Non-Invasive Blood Pressure Difference During General Anesthesia

Study Overview
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Brief Summary
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Brachial non-invasive blood pressure (NIBP) monitoring is recommended as part of the American Society of Anesthesiology (ASA) basic monitoring package. Although brachial NIBP is often practical, some surgeries and patients may require NIBP measurement elsewhere (e.g. the ankle). Several studies have shown that ankle NIBP overestimates brachial NIBP measurements. Algorithms have been proposed, based on correlation studies, to estimate brachial NIBP from ankle NIBP during general anesthesia and mechanical ventilation. These algorithms, however, are based on both heterogeneous populations and surgeries. Our aim was to determine if ankle brachial NIBP difference occurs in in young ASA physical status 1 patients undergoing general anesthesia in the supine position. We also aim to determine if this difference is constant during anesthesia or if it varies according to different predefined time points.

Official Title
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Ankle/Brachial Non-Invasive Blood Pressure Difference During General Anesthesia: a Prospective Cohort Observational Study in Young Healthy Patients

Conditions
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Surgery

Intervention / Treatment
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* Device: Ankle Non-invasive Blood pressure measurement
* Device: Arm Non-invasive Blood pressure measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiology (ASA) pysical status score 1 Patient undergoing elective surgery requiring general anesthesia in supine position Exclusion Criteria: Patient refusal systemic pathology Body mass index (BMI) superior to 30 Surgeon requiring a position other than supine

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 40 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| General anesthesia<br>Patient (15 to 40 years old) undergoing elective surgery requiring general anesthesia in supine position. | Device: Ankle Non-invasive Blood pressure measurement<br>* Non-invasive blood pressure measured simultaneously at the arm (model IntelliVue M8105a MP5 Phillips, calibrated).<br>Device: Arm Non-invasive Blood pressure measurement<br>* Non-invasive blood pressure measured simultaneously at the ankle (model IntelliVue M8105a MP5 Phillips, calibrated).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ankle Brachial non-invasive blood pressure difference - time point 1 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, before induction of anesthesia | 1 day | 
| Ankle Brachial non-invasive blood pressure difference - time point 2 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, after induction of anesthesia | 1 day | 
| Ankle Brachial non-invasive blood pressure difference - time point 3 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, after securing airway | 1 day | 
| Ankle Brachial non-invasive blood pressure difference - time point 4 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, at surgical incision | 1 day | 
| Ankle Brachial non-invasive blood pressure difference - time point 5 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, 10 minutes after surgical incision | 1 day | 
| Ankle Brachial non-invasive blood pressure difference - time point 6 | Difference between the non-invasive blood pressure measured at the ankle and at the arm, at reversal of anesthesia | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain at the arm (yes/no) | Answer 'yes' or 'no' to the question 'pain at the arm' in postoperative period | 1 day | 
| Pain at the ankle (yes/no) | Answer 'yes' or 'no' to the question 'pain at the ankle' in postoperative period | 1 day | 
| Ankle Brachial NIBP difference variation | Determine if Ankle Brachial NIBP difference remains constant or varies during different intraoperative periods | 1 day |