Objectives. Relationships of mechanical ventilation to pneumothorax in neonates and care procedures in particular are rarely studied. We aimed to evaluate the relationship of selected ventilator variables and risk events to pneumothorax. Methods. Pneumothorax was defined as accumulation of air in pleural cavity as confirmed by chest radiograph. Relationship of ventilator mode, selected settings, and risk procedures prior to detection of pneumothorax was studied using matched controls. Results. Of 540 neonates receiving mechanical ventilation, 10 (1.85%) were found to have pneumothorax. Respiratory distress syndrome, meconium aspiration syndrome, and pneumonia were the underlying lung pathology. Pneumothorax mostly (80%) occurred within 48 hours of life. Among ventilated neonates, significantly higher percentage with pneumothorax received mandatory ventilation than controls (70% versus 20%; ). Peak inspiratory pressure >20?cm and overventilation were not significantly associated with pneumothorax. More cases than controls underwent care procedures in the preceding 3 hours of pneumothorax event. Mean airway pressure change ( ) and endotracheal suctioning ( ) were not significantly associated with pneumothorax. Reintubation ( ), and bagging ( ) were significantly associated with pneumothorax. Conclusion. Pneumothorax among ventilated neonates occurred at low frequency. Mandatory ventilation and selected care procedures in the preceding 3 hours had significant association. 1. Introduction Pneumothorax is the most common air-leak syndrome resulting in significant morbidity and mortality in neonates [1–3]. Increased mortality and chronic lung disease with pneumothorax (about 13 times) in very low birth weight (VLBW) neonates have been reported by Powers and Clemens [3]. Its relationship with underlying primary lung disorders is well recognized [1, 4, 5]. However, higher incidences of pneumothorax in ventilated neonates [3–5] with mild increase among those receiving continuous positive airway pressure (CPAP) and dramatic increase with mandatory modes of ventilation have been addressed by only few studies [1, 4]. Similarly studies addressing association of pneumothorax to various ventilation strategies are scarce. Such strategies with high incidence of pneumothorax include high peak inspiratory pressure (PIP) and mean airway pressure (MAP), active expiratory reflex, administration of bag and mask ventilation, endotracheal tube displacement, an increase in clinical interventions [6–9], long inspiratory time [10], and high frequency ventilation [11]. Ventilator
References
[1]
J. D. Miller and W. A. Carlo, “Pulmonary complications of mechanical ventilation in neonates,” Clinics in Perinatology, vol. 35, no. 1, Article ID 27381, pp. 273–281, 2008.
[2]
H. Maksi?, S. Helji?, S. Maksi?, and F. Jonuzi, “Pulmonary complications during mechanical ventilation in the neonatal period,” Medicinski Arhiv, vol. 54, no. 5-6, pp. 271–272, 2000.
[3]
W. F. Powers and J. D. Clemens, “Prognostic implications of age at detection of air leak in very low birth weight infants requiring ventilatory support,” Journal of Pediatrics, vol. 123, no. 4, pp. 611–617, 1993.
[4]
G. Klinger, S. Ish-Hurwitz, M. Osovsky, L. Sirota, and N. Linder, “Risk factors for pneumothorax in very low birth weight infants,” Pediatric Critical Care Medicine, vol. 9, no. 4, pp. 398–402, 2008.
[5]
A. Greenough and A. D. Millner, “Pulmonary airleaks,” in Roberton’s Text Book of Neonatology, J. M. Rennie, Ed., pp. 487–491, Elsevier Churchill Livingstone, Philadelphia, Pa, USA, 4th edition, 2005.
[6]
M. Watkinson and I. Tiron, “Events before the diagnosis of a pneumothorax in ventilated neonates,” Archives of Disease in Childhood: Fetal and Neonatal Edition, vol. 85, no. 3, pp. F201–F203, 2001.
[7]
R. Niwas, A. M. Nadroo, V. G. Sutija, M. Gudavalli, and P. Narula, “Malposition of endotracheal tube: association with pneumothorax in ventilated neonates,” Archives of Disease in Childhood: Fetal and Neonatal Edition, vol. 92, no. 3, pp. F233–F234, 2007.
[8]
S. Ngerncham, P. Kittiratsatcha, and P. Pacharn, “Risk factors of pneumothorax during the first 24 hours of life,” Journal of the Medical Association of Thailand, vol. 88, no. 8, pp. S135–S141, 2005.
[9]
A. Greenough, A. D. Milner, and G. Dimitriou, “Synchronized mechanical ventilation for respiratory support in newborn infants,” Cochrane Database of Systematic Reviews, no. 4, Article ID CD000456, 2004.
[10]
C. O. Kamlin and P. G. Davis, “Long versus short inspiratory times in neonates receiving mechanical ventilation,” Cochrane Database of Systematic Reviews, no. 4, Article ID CD004503, 2004.
[11]
U. H. Thome, W. A. Carlo, and F. Pohlandt, “Ventilation strategies and outcome in randomised trials of high frequency ventilation,” Archives of Disease in Childhood: Fetal and Neonatal Edition, vol. 90, no. 6, pp. F466–F473, 2005.
[12]
A. Hill, J. M. Pariman, and J. J. Volpe, “Relationship of pneumothorax to occurrence of intraventricular hemorrhage in the premature newborn,” Pediatrics, vol. 69, no. 2, pp. 144–149, 1982.
[13]
Z. Il?e, G. Gündogdu, C. Kara, B. Ilikkan, and S. Celayir, “Which patients are at risk? Evaluation of the morbidity and mortality in newborn pneumothorax,” Indian Pediatrics, vol. 40, no. 4, pp. 325–328, 2003.
[14]
H. Esme, ?. Do?ru, ?. Eren, M. Korkmaz, and O. Solak, “The factors affecting persistent pneumothorax and mortality in neonatal pneumothorax,” Turkish Journal of Pediatrics, vol. 50, no. 3, pp. 242–246, 2008.
[15]
J. H. Baumer, “International randomised controlled trial of patient triggered ventilation in neonatal respiratory distress syndrome,” Archives of Disease in Childhood: Fetal and Neonatal Edition, vol. 82, no. 1, pp. F5–F10, 2000.
[16]
B. N. J. Shaw, R. W. I. Cooke, A. B. Gill, and M. Saeed, “Randomised trial of routine versus selective paralysis during ventilation for neonatal respiratory distress syndrome,” Archives of Disease in Childhood, vol. 69, no. 5, pp. 479–482, 1993.
[17]
A. Malek, N. Afzali, M. Meshkat, and N. H. Yazdi, “Pneumothorax after mechanical ventilation in newborns,” Iranian Journal of Pediatrics, vol. 21, no. 1, pp. 45–50, 2011.
[18]
C. J. Morley, P. G. Davis, L. W. Doyle, L. P. Brion, J.-M. Hascoet, and J. B. Carlin, “Nasal CPAP or intubation at birth for very preterm infants,” The New England Journal of Medicine, vol. 358, no. 7, pp. 700–708, 2008.
[19]
A. Greenough, S. Wood, C. J. Morley, and J. A. Davis, “Pancuronium prevents pneumothoraces in ventilated premature babies who actively expire against positive pressure inflation,” The Lancet, vol. 1, no. 8367, pp. 1–3, 1984.
[20]
N. McIntosh, J.-C. Becher, S. Cunningham et al., “Clinical diagnosis of pneumothorax is late: use of trend data and decision support might allow preclinical detection,” Pediatric Research, vol. 48, no. 3, pp. 408–415, 2000.
[21]
R. A. Primhak, “Factors associated with pulmonary air leak in premature infants receiving mechanical ventilation,” Journal of Pediatrics, vol. 102, no. 5, pp. 764–767, 1983.