Evaluation of V/Q Mismatch as Predictor of Pulmonary Postoperative Complications in Patients Undergoing Major Surgery

Study Overview
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Brief Summary
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Pulmonary postoperative complications (PPC) are among the main causes of surgical complications affecting both postoperative morbidity and mortality. Little is known about the effect of intraoperative VQ mismatch on the occurrence of PPC. In this trial the investigators will evaluate if intraoperative VQ mismatch may predict PPC in a population of patients undergoing major surgery.

Detailed Description
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Pulmonary postoperative complications (PPC) are among the main causes of surgical complications affecting both postoperative morbidity and mortality. Little is known about the effect of intraoperative VQ mismatch on the occurrence of PPC. PPC are classically considered associated to the occurrence of intraoperative atelectasis, and therefore to the development of a certain amount of shunt, but this concept have been recently questioned. Recent studies showed indeed that, despite age is one of the main determinants of PPCs, increasing age is not associated to the increase of intraoperative shunt. Shunt therefore may not be the main determinant of PPC. In this trial the investigators will evaluate if other causes of intraoperative VQ mismatch (e.g. low V/Q, high V/Q, dead space) may predict PPC in a population of patients undergoing major surgery.

Official Title
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Evaluation of Intraoperative V/Q Mismatch and Compliance Trajectories as Predictors of Pulmonary Postoperative Complications in Patients Undergoing Major Surgery

Conditions
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Anesthesia, Postoperative Complications, Mechanical Ventilation Complication

Intervention / Treatment
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* Device: Measure of ventilation/perfusion (V/Q) mismatch using Beacon ALPE (Automatic Lung Paramether Estimator)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-90 years Major elective surgery with general anesthesia Intraoperative cannulation of the radial artery for invasive pressure monitoring Exclusion Criteria: Thoracic surgery with one lung ventilation Refuse to participate Emergency surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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 |
| --- | --- |
| Patients undergoing surgery<br>Mechanical measures, VQ mismatch evaluation | Device: Measure of ventilation/perfusion (V/Q) mismatch using Beacon ALPE (Automatic Lung Paramether Estimator)<br>* Evaluation of intraoperative V/Q mismatch using the Beacon ALPE during anesthesia.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of Pulmonary postoperative complications | Definition derived from the ESA-ESICM joined taskforce on perioperative outcome measures. | In the first 7 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraoperative mechanical measures (pressures) | Intraoperative evaluation of: Peak pressure (Ppeak), cmH2O Plateau pressure (Pplat), cmH2O Total PEEP (PEEP total), cmH2O | During surgery | 
| Intraoperative drug administration | Evalation of anesthetic drugs administered during surgery by the treating physician. | During surgery | 
| Intraoperative arterial pressure | Evaluation during surgery of: systolic pressure (mmHg) diastolic pressure (mmHg) | During surgery | 
| Intraoperative heart rate | evaluation of - Heart rate (beats/min) | During surgery | 
| V/Q mismatch | Evaluation of V/Q mismatch | During anesthesia | 
| fluid balance | Evaluation of patients fluid intake and fluid balance during surgery | During surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anesthesia, Pulmonary postoperative complications, ALPE, Ventilation/perfusion mismatch