Incidence of Postoperative Persistent Diaphragmatic Dysfunctions in Cardiac Surgery

Study Overview
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Brief Summary
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Postoperative respiratory complication is a common complication that occurs in 6% of patients after cardiac surgery and increases morbidity and mortality and hospital length of stay. Diaphragmatic dysfunction (DD) is one of the main risk factors for post-operative respiratory distress syndrome. It alters the ventilatory mechanical function of patients and promotes pneumonia. In the literature, risk factors included older age, diabetes, harvesting of a mammary artery, intraoperative ice solution using, prolonged cardiopulmonary bypass and intra-operative phrenic nerve injury. Ultrasonography using the two-dimensional (2D) mode is a diagnosis tool for DD. For patients with DD, ultrasound criteria are: 1) an excursion during quiet breathing < 9 mm for woman and < 10 mm for man, 2) an excursion after sniff test < 16 mm for woman and < 18 mm for man and 3) an excursion during deep breathing < 37 mm for woman and < 47 mm for man. A paradoxical diaphragmatic ascent may also be observed during inspiration. DD may be transient, linked to mechanical factors such as pain, the presence of pleural and mediastinal drains, lying down or sternotomy; with recovery from 5 postoperative days. It may be more prolonged (persistent after 7 days) in connection with a partial or complete phrenic nerve injury and / or diaphragmatic devascularization after mammary artery harvesting. The aim of this prospective study is to determine the incidence of persistent DD after cardiac surgery.

Detailed Description
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Diaphragmatic amplitude will be assessed by ultrasonography during quiet breathing and after sniff test, before the surgery and at day 7 post-surgery in all patients. Patients with persistent DD at day 7 post-surgery will have additional Respiratory Functional Explorations.

Official Title
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Incidence of Postoperative Persistent Diaphragmatic Dysfunctions in Cardiac Surgery

Conditions
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Surgery, Cardiac

Intervention / Treatment
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* Diagnostic Test: Ultrasonography using the two-dimensional (2D) mode
* Diagnostic Test: Respiratory Functional Explorations


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing cardiac surgery requiring sternotomy Consent for participation Affiliation to the social security system Exclusion Criteria: Contraindication to preoperative respiratory functional explorations Pregnant or breastfeeding women Patients under protection of the adults (guardianship, curators or safeguard of justice) Communication difficulties or neuropsychiatric disorder

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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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non diaphragmatic dysfunction at day 7 post-surgery<br>Diaphragmatic displacement after sniff test ≥ 16 mm for women and ≥ 18 mm for men | Diagnostic Test: Ultrasonography using the two-dimensional (2D) mode<br>* Diaphragmatic amplitude assessed by ultrasonography during quiet breathing and after sniff test, before the surgery and at day 7 post-surgery in all patients.<br>|
| Persistent diaphragmatic dysfunction at day 7 post-surgery<br>Diaphragmatic displacement after sniff test < 16 mm for women and < 18 mm for men | Diagnostic Test: Ultrasonography using the two-dimensional (2D) mode<br>* Diaphragmatic amplitude assessed by ultrasonography during quiet breathing and after sniff test, before the surgery and at day 7 post-surgery in all patients.<br>Diagnostic Test: Respiratory Functional Explorations<br>* Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV) and total lung capacity (TLC) measured at day 7<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of persistent diaphragmatic dysfunctions after cardiac surgery | Diaphragmatic excursion measured during sniff test (displacement, mm) | 8 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of respiratory complications | Occurrence of pneumonia, atelectasis requiring bronchial clearing by fibroscopy, reintubation, prolonged mechanical ventilation (>24h) or prolonged non-invasive ventilation (>48h) | up to 2 months | 
| Intensive Care Unit (ICU) length of stay | Duration of ICU stay measured in days | up to 2 months | 
| Hospital length of stay | Duration of hospitalization measured in days | up to 2 months | 
| Respiratory function test in the group with persistent diaphragmatic dysfunction | Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV) and total lung capacity (TLC) measured at day 7 and compared to day 0 | 8 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diaphragmatic paralysis, Respiratory complications