Proof-of-principle of a lung sealant based on functionalized polyoxazolines: experiments in an ovine acute aerostasis model

• Published in: Interdisciplinary cardiovascular and thoracic surgery Vol. 38; no. 6
• Main Authors: Hermans, Bob P, Ten Broek, Richard, Li, Wilson W L, Rooen, Edwin A, Vos, Shoko, Van Der Heijden, Erik, Van Goor, Harry, Erhagen, Ad F T M
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 05.06.2024
• Subjects: Thoracic Non-oncology; lung surgery; in vivo; lung sealing; biomaterials; air leak
• ISSN: 2753-670X; 2753-670X
• DOI: 10.1093/icvts/ivae113

More effective lung sealants are needed to prevent prolonged pulmonary air leakage (AL). Polyoxazoline impregnated gelatin patch (NHS-POx) was promising for lung sealing ex vivo. The aim of this study is to confirm sealing effectiveness in an in vivo model of lung injury. An acute aerostasis model in healthy adult female sheep was used, performing bilateral thoracotomy, amputation lesions (bronchioles Ø > 1.5 mm), sealant application, digital chest tube for monitoring AL, spontaneous ventilation, obduction and bursting pressure (BP) measurement. Two experiments were performed: 1) Three sheep with two lesions per lung (N = 4 NHS-POx double-layer, N = 4 NHS-POx single-layer, N = 4 untreated) and 2) three with one lesion per lung (N = 3 NHS-POx single-layer, N = 3 untreated). In pooled linear regression, AL was analyzed per lung (N = 7 NHS-POx, N = 5 untreated) and BP per lesion (N = 11 NHS-POx, N = 7 untreated). Baseline AL was similar between groups (mean 1.38-1.47L/min, p = 0.90). NHS-POx achieved sealing in one attempt in 8/11 (72.7%) and in 10/11 (90.9%) in > 1 attempt. Application failures were only observed on triangular lesions requiring three folds around the lung. No influences of methodological variation between experiments was detected in linear regression (p > 0.9). AL over initial 3 h of drainage was significantly reduced for NHS-POx (median: 7 mL/min, interquartile range [IQR]: 333 mL/min) versus untreated lesions (367 mL/min, IQR: 680 mL/min, p = 0.036). BP was higher for NHS-POx (mean: 33, SD: 16cmH2O) versus untreated lesions (mean: 19, SD: 15cmH2O, p = 0.081). NHS-POx was effective for reducing early AL, and a trend was seen for improvement of bursting strength of the covered defect. Results were affected by application characteristics and lesion geometry.