An Animal Model for the Study of Lung Protective Therapies During One Lung Ventilation (OLV) in Children

Abstract

One-lung ventilation (OLV) is the intentional collapse of one lung during surgical procedures in the chest. The objective of this report is to demonstrate that a piglet model of pediatric OLV mimics the clinical sequelae, and thus is valid to study lung protective interventions. Pediatric pigs (n = 7; 21 ± 1 d old; 7.7 ± 0.5 kg) were instrumented and exposed to OLV (left lung collapsed) for 3 hrs, followed by 30 min of bilateral lung ventilation (BLV) before sacrifice and tissue harvest. Pulmonary compliance (Cp) and resistance (Rp) were measured half-hourly and plasma samples were drawn hourly for inflammatory cytokine analysis. Cp dropped to 86% and Rp rose to 148% of baseline with OLV, which is consistent with clinical observations given the anatomical differences of the pig thorax. Plasma levels of TNF-α and IL- 6 rose throughout the protocol, consistent with clinical observations. Lung histology showed greater atelectasis in the collapsed lungs following 30 min of BLV. The piglet model is valid for the study of OLV-induced lung injury and may be useful for the study of potential therapies to improve outcomes in the pediatric population.