Dataset Information

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

ABSTRACT:

Objectives

More effective lung sealants are needed to prevent prolonged pulmonary air leakage (AL). Polyoxazoline-impregnated gelatin patch (N-hydroxysuccinimide ester functionalized poly(2-oxazoline)s; 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.

Methods

An acute aerostasis model was used in healthy adult female sheep, involving bilateral thoracotomy, amputation lesions (bronchioles Ø > 1.5 mm), sealant application, digital chest tube for monitoring AL, spontaneous ventilation, obduction and bursting pressure measurement. Two experiments were performed: (i) 3 sheep with 2 lesions per lung (N = 4 NHS-POx double-layer, N = 4 NHS-POx single-layer, N = 4 untreated) and (ii) 3 with 1 lesion per lung (N = 3 NHS-POx single-layer, N = 3 untreated). In pooled linear regression, AL was analysed per lung (N = 7 NHS-POx, N = 5 untreated) and bursting pressure per lesion (N = 11 NHS-POx, N = 7 untreated).

Results

Baseline AL was similar between groups (mean 1.38-1.47 l/min, P = 0.90). NHS-POx achieved sealing in 1 attempt in 8/11 (72.7%) and in 10/11 (90.9%) in >1 attempt. Application failures were only observed on triangular lesions requiring 3 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, length of interquartile range: 333 ml/min] versus untreated lesions (367 ml/min, length of interquartile range: 680 ml/min, P = 0.036). Bursting pressure was higher for NHS-POx (mean: 33, SD: 16 cmH2O) versus untreated lesions (mean: 19, SD: 15 cmH2O, P = 0.081).

Conclusions

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.

SUBMITTER: Hermans BP

PROVIDER: S-EPMC11250206 | biostudies-literature | 2024 Jun

REPOSITORIES: biostudies-literature

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Publications

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

Hermans Bob P BP Ten Broek Richard P G RPG Li Wilson W L WWL Roozen Edwin A EA Vos Shoko S Van Der Heijden Erik H F M EHFM Van Goor Harry H Verhagen Ad F T M AFTM

Interdisciplinary cardiovascular and thoracic surgery 20240601 6

<h4>Objectives</h4>More effective lung sealants are needed to prevent prolonged pulmonary air leakage (AL). Polyoxazoline-impregnated gelatin patch (N-hydroxysuccinimide ester functionalized poly(2-oxazoline)s; 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.<h4>Methods</h4>An acute aerostasis model was used in healthy adult female sheep, involving bilateral thoracotomy, amputation lesions (bronchioles ...[more]

PMID: 38833687

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Dataset Information

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

Objectives

Methods

Results

Conclusions

Publications

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

Similar Datasets

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