Perioperative Atelectasis in Orthopaedic Surgery: a Prospective Study

Study Overview
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Brief Summary
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This study aims at comparing a perioperative pulmonary atelectasis score, measured by pulmonary ultrasound, in patients operated undergoing orthopedic surgery under general anesthesia, spinal anesthesia or peripheral nerve block. The association between the atelectasis score and previously identified risk factors will be studied.

Detailed Description
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Atelectasis is one of the most common pulmonary complications in the perioperative period, occurring in 85% to 90% of patients under general anesthesia. It can be responsible for hypoxemia and be associated with postoperative pulmonary complications such as pneumonia. The consequences are a prolongation of the hospital stay and an increase in mortality. The appearance of perioperative atelectasis is mainly secondary to the induction of general anesthesia with an incidence up to 90%. The different causes are, for example, the administration of muscle relaxants, mechanical ventilation and the position of the patient. In orthopedic surgery, many procedures are performed under spinal anesthesia or under peripheral nerve block. At present, there are no studies measuring the incidence of atelectasis in patients operated under these two techniques of locoregional anesthesia, with the exception of parturients undergoing cesarean section. This study aims at comparing a perioperative pulmonary atelectasis score, measured by pulmonary ultrasound, in patients operated undergoing orthopedic surgery under general anesthesia, spinal anesthesia or peripheral nerve block. The association between the atelectasis score and previously identified risk factors will be studied.

Official Title
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Perioperative Atelectasis in Patients Undergoing Orthopaedic Surgery: Prospective Cohort Study

Conditions
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Atelectasis

Intervention / Treatment
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* Other: Lung ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over the age of 18; Patients scheduled for an elective operation at the Orthopedic Hospital of CHUV; Signature of the study consent Exclusion Criteria: Thoracic deformities preventing the performance of pulmonary ultrasound (dressings, drains, fractures, etc.); Refusal to participate; Patient does not speak French. Inability to discern

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 |
| --- | --- |
| General anesthesia<br> | Other: Lung ultrasound<br>* Lung atelectasis score<br>|
| Spinal anesthesia<br> | Other: Lung ultrasound<br>* Lung atelectasis score<br>|
| Peripheral nerve block<br> | Other: Lung ultrasound<br>* Lung atelectasis score<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lung atelectasis score | Atelectasis score based on validated ultrasound quantification (comparing different anesthesia techniques) | immediately after the surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lung atelectasis score | Atelectasis score | Four timepoints: at baseline, immediatly before surgery (after anesthesia induction), immediately after the surgery, and at the recovery room |