Atelectasis After Pulmonary Lobectomy: The Effect Of Air During One-Lung Ventilation (OLV) On Postoperative Atelectasis

Atelectasis After Pulmonary Lobectomy: The Effect Of Air During One-Lung Ventilation (OLV) On Postoperative Atelectasis.

Patients scheduled for lung lobe resection using video assisted thoracic surgery will be randomly assigned to be ventilated with either only oxygen or a mixture of air and oxygen.

The primary purpose of this study is to determine if the incidence of postoperative collapse (in the non-surgical lung) is decreased when using a mixture of air and oxygen compared to using only oxygen (which is our control measurement) during one-lung ventilation.

One of the concerns with all thoracic procedures employing One Lung Ventilation (OLV) is intra-operative hypoxia due to the large shunt that develops when only one lung is being ventilated. Ventilation with a higher fraction of inspired oxygen (FIO2) is one of the commonly chosen strategies for the treatment of hypoxemia during (OLV) for thoracic surgery. Using an FIO2 of 1.0 at all times during (OLV), however, may increase the risk of absorption atelectasis intra and postoperatively which itself leads to persistent hypoxia and potentially pneumonia.

The aim of this study is therefore to determine the impact of adding air to the inspired fraction of oxygen during (OLV) primarily on the incidence of postoperative atelectasis of the nonsurgical lung after lung resection using video assisted thoracic surgery and secondarily on intraoperative and postoperative oxygenation.

Inclusion Criteria:

• Age 18 years or older
• Competent to give consent to enroll in study
• Booked for open thoracotomy procedure for lobectomy
• American Society of Anesthesiologists comorbidity score 1-4

Exclusion Criteria:

• Unable or unwilling to give consent
• Pregnant women
• Inability to insert an arterial line
• Severe COPD (FEV1 < .7% predicted, or FEV1/FVC < 0.70)
• Presence of other significant pulmonary impairment (PaO2 on room air 50 mmHg, PaCO2 > 50 mmHg or known pulmonary HTN mean PAP > 25 mmHg)
• Presence of significant cardiovascular disease (+MIBI that is non-revascularized, CCS ≥ 3 angina, NYHA ≥ 3 CHF, EF (by angiography or echocardiogram < 40%)
• Chronic renal failure (serum Cr > 200)
• Altered liver function