Role of Lung Ultrasound Imaging for Intraoperative Monitoring of Atelectasis During Laparoscopic Surgery

Completed

• Conditions: Atelectasis
• Interventions: Other: Lung ultrasound imaging examinations

• Registration Number: NCT01749436
• Lead Sponsor: Centre hospitalier de l'Université de Montréal (CHUM)

Brief Summary

General anesthesia results in the development of atelectasis in the dependent areas of the lungs exposing patients to an increased risk of hypoxemia. During laparoscopic procedures, pneumoperitoneum increases already present atelectasis.

Several methods have been suggested to reduce the impact of atelectasis during surgery. However, few intraoperative modalities for the diagnosis and monitoring of atelectasis are available. Lung ultrasound imaging is a promising non-invasive, non-radiant, portable and easy to use tool that as yet to be studied in the intraoperative setting.

This observational study will aim to clarify the role of lung ultrasound imaging during laparoscopic surgery for the diagnostic and monitoring of atelectasis.

This study is designed to:

* Demonstrate a link between the lung ultrasound aeration score, the partial pressure of oxygen in arterial blood (PaO2) / fraction of inspired oxygen (FiO2) ratio and the oxygenation index.

* In the event of intraoperative desaturation, study the impact of positive end-expiratory pressure (PEEP) and/or increase of FiO2 on the aeration score.

* Study the impact of pain on diaphragmatic function and the aeration score.

Our hypothesis is that lung ultrasound imaging allows detection of lung aeration changes associated with induction of general anesthesia, pneumoperitoneum, emergence from anesthesia and changes occurring during the stay in the recovery room.

Detailed Description

On arrival in the operating theatre, each patient will undergo a baseline lung ultrasound examination.

The anesthetic technique and monitoring will be standardized. The radial artery will be cannulated after induction of anesthesia for blood gas monitoring.

Lung ultrasound examinations will be performed 5 minutes following induction of general anesthesia and 5 minutes after insufflation of the abdomen with carbon dioxide. In the event of a desaturation needing an intervention (increase of FiO2 or PEEP), ultrasound imaging will be repeated before and after the intervention. Presence of a pneumothorax or endobronchial intubation will be assessed during each examination. Fifteen minutes after arrival and immediately before discharge from the recovery room, lung ultrasound examinations will also be performed.

FiO2 and vital signs will be recorded at each ultrasound examination. Arterial blood samples will be collected simultaneously. Pain rating using the visual analog scale and diaphragmatic function will be assessed during the preoperative ultrasound examination and before discharge from the recovery room.

Study Timeline

• Study First Submitted: 2012-12-12
• Study First Submitted QC: 2012-12-12
• Study First Posted: 2012-12-13
• Study Start: 2013-04
• Status Verified: 2013-09
• Primary Completion: 2013-09
• Study Completion: 2013-09
• Last Update Submitted: 2013-09-12
• Last Update Posted: 2013-09-16

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Patients aged 18 years and older
• Scheduled for laparoscopic surgery
• Physical status 1-3

Exclusion Criteria

• Previous thoracic procedure (thoracic drain, thoracotomy, thoracoscopy)
• Contraindication to the placement of an arterial line
• Very severe chronic obstructive pulmonary disease

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Lung ultrasound imaging	Lung ultrasound imaging examinations	Lung ultrasound imaging examinations performed during the perioperative period for the monitoring of atelectasis associated with laparoscopic surgery

Primary Outcome Measures

Name	Time	Method
Lung aeration	From arrival in the operating theatre to immediately before discharge from the recovery room (Day 0)	Estimate lung aeration by ultrasound imaging using a four point aeration score (0 = normal lung, 1 = moderate aeration loss, 2 = severe aeration loss, 3 = complete aeration loss and consolidation)

Secondary Outcome Measures

Name	Time	Method
Diaphragmatic function	On arrival in the operating theatre and immediately before discharge from the recovery room (Day 0)	Assess diaphragmatic function by ultrasound imaging
Incidence of pneumothorax	From 5 minutes following induction of anesthesia to immediately before discharge from the recovery room (Day 0)	Estimate the incidence of pneumothorax by ultrasound imaging
Incidence of endobronchial intubation	From 5 minutes following induction of anesthesia to immediately before discharge from the recovery room (Day 0)	Estimate the incidence endobronchial intubation by ultrasound imaging
Gas exchange	From 5 minutes following induction of anesthesia to immediately before discharge from the recovery room (Day 0)	Assess the impact of the different stages of anesthesia and surgery on gas exchange by measuring arterial blood gases.

Trial Locations

Locations (1)

Centre Hospitalier de l'Université de Montréal (CHUM); 🇨🇦 Montreal, Quebec, Canada