Validity of Aortic Pulse Wave Velocity in Predicting the 6- Minute Walking Test Before Major Non-cardiac Surgery

Study Overview
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Brief Summary
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Methods: Prospective observational study in adult patients requiring preoperative evaluation Objectives: To determine the correlation between the aortic pulse wave velocity (AoPWV) and the distance walked in the 6-minute walk test (6MWT) Sample Size: For a desired precision of estimate of ± 0.10 (95% confidence interval) around a postulated validity correlation coefficient of r = 0.70 (for an AoPWV in the distance prediction of 6MWT) a sample of 100 patients. By allowing a 25% wear rate, a final sample size of 125 participants is required Inclusion criteria: Patients older than 18 years undergoing any surgery and who require pre-anesthesia Statistical analysis If the variables have a normal distribution, the Pearson correlation coefficient (r2) is used, which is between -1 and 1. Where -1 indicates the highest possible negative linear relationship (increasing the value of a variable decreases the another), 0 that there is no association, +1 positive correlation. From 0.7 negative or positive, it is said that the association is strong. Linear regression models of ordinary least squares will be applied to obtain the validity coefficient (r) and the standard error of the estimate (SEE): the typical error associated with the prediction the AoPWV with the distance traveled in the 6MWD test in each individual patient. The analysis of the receiver operating characteristic curve (ROC) will be used to derive cutoff points for an AoPWV value for the prediction of a 6MWD less than 427 meters

Official Title
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Validity of Aortic Pulse Wave Velocity in Predicting the 6- Minute Walking Test Before Major Non-cardiac Surgery (6WAVE)

Conditions
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Perioperative/Postoperative Complications, Surgery, Exercise Tolerance

Intervention / Treatment
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* Diagnostic Test: Aortic pulse wave velocity measurement
* Diagnostic Test: 6 minutes walking test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients older than 18 years undergoing elective surgery that receive a preoperative visit by anesthesiologists. Exclusion Criteria: Patients undergoing emergency surgery Patients under 18 years of age Patients who refuse to participate Patients unable to perform the 6MWT Claudication of the lower extremities and inability to maintain a constant pace of walking on level ground

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients undergoing elective surgery<br>All patients older than 18 years undergoing elective surgery that receive a preoperative visit by anesthesiologists in which Aortic pulse wave velocity measurement and the 6 minutes walking test (6MWT) is carried out | Diagnostic Test: Aortic pulse wave velocity measurement<br>* Aortic pulse pulse wave velocity (AoPWV) measured by photoplethysmography<br>Diagnostic Test: 6 minutes walking test<br>* This test is performed routinely in the pre-rehabilitation units or in external anesthesiology consultations during the preoperative visit. In essence, it consists in measuring the maximum distance the patient is able to walk in 6 minutes, in a short walk in a corridor, simultaneously assessing the heart rate, oxygen saturation and the degree of dyspnea. In general, healthy people can walk between 400 and 700 meters in 6 minutes, depending on age, height and sex.<br>* Other names: 6MWT;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AoPWV validity: relationship between AoPWV and 6MWT distance | The validity of AoPWV-physiological parameter measured non-invasively by photoplethysmography-will be evaluated to predict the distance traveled in 6MWT in adult patients undergoing any type of elective surgery | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AoPWV threshold | AoPWV threshold associated with a 6MWD threshold of 427 meters that defines the patient at risk | 1 day |