Comparison of exogenous surfactant and positive end-expiratory pressure therapies in a model of human breast milk-induced acute lung injury in rabbits

• Published in: British Journal of Anaesthesia Vol. 84; no. 5; pp. 600 - 607
• Main Authors: Chin, C., O’Hare, B., Lerman, J., Endo, J.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2000; Oxford University Press; Oxford Publishing Limited (England)
• Subjects: Administration, Inhalation; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; aspiration; Biological and medical sciences; compliance; Emergency and intensive respiratory care; Intensive care medicine; lung; Lung - pathology; lung, aspiration; lung, compliance; Medical sciences; Milk, Human; paediatric; Pneumonia, Aspiration - etiology; Pneumonia, Aspiration - pathology; Pneumonia, Aspiration - therapy; positive end-expiratory pressure; Positive-Pressure Respiration; Pulmonary Surfactants - therapeutic use; Rabbits; Specific Pathogen-Free Organisms; surgery; surgery, paediatric; Treatment Outcome; ventilation; ventilation, positive end-expiratory pressure; lung, compliance; lung, aspiration; ventilation, positive end-expiratory pressure; surgery, paediatric; Human origin; Lung disease; Respiratory disease; Rabbit; Artificial ventilation; Lagomorpha; Trauma; Positive end expiratory pressure; Vertebrata; Chemotherapy; Mammalia; Treatment; Pulmonary surfactant; Aspiration pneumonia; Animal; Breast milk
• ISSN: 0007-0912; 1471-6771
• DOI: 10.1093/bja/84.5.600

To evaluate surfactant and positive end-expiratory pressure (PEEP) as potential therapies for the acute lung injury after tracheal instillation of 0.8 ml kg–1 human breast milk (HBM) acidified to pH 1.8, adult white rabbits were anaesthetized, tracheostomized, ventilated and randomized to (six rabbits per treatment): (i) no treatment after HBM (control); (ii) exogenous Bovine surfactant (100 mg kg–1) 1 h after HBM; (iii) PEEP-pre (0.5 kPa PEEP) before and after HBM; or (iv) PEEP-post (0.5 kPa PEEP) after HBM. A fifth group of six rabbits received no tracheal instillate (no aspirate). The alveolar to arterial oxygen tension gradient (A–aDO2) and dynamic compliance were measured pre-injury and hourly for 4 h. At post-mortem, the lungs were examined histologically. A–aDO2 in all four HBM-injured groups increased to a maximum at 1 h post-injury; A–aDO2 then returned towards the baseline in the surfactant and PEEP-post groups, but remained increased in the PEEP-pre and control groups. Dynamic compliance decreased in all four HBM-injured groups. A–aDO2 and compliance were unchanged in the no aspirate group. Bronchoalveolar architecture after surfactant therapy was normal. We conclude that surfactant is a more effective therapy for HBM-induced lung injury than either 0.5 kPa PEEP-post or PEEP-pre injury.