Development of a tension pneumothorax despite intercostal drain insertion.

To cite: Scott AJ, Davies SJ, Vassiliu P. BMJ Case Reports Published online: 4 December 2012 doi:10.1136/bcr-2012006358 DESCRIPTION A 21-year-old man presented to a trauma department in Johannesburg with two sucking stab wounds on each side of his posterior thorax. The patient was in respiratory distress with oxygen saturation of 91% on 15 L O2. Blood pressure was 105/72 mm Hg, pulse 112/min and blood gas analysis demonstrated a mixed metabolic and respiratory acidosis. A left haemopneumothorax was detected clinically although there was no evidence of tensioning. The stab wounds were covered with damp, three-sided dressings and an intercostal drain (ICD) was inserted into the left hemithorax, draining ∼500 ml of blood. A radiograph (figure 1) confirmed correct ICD placement but also showed a right-sided pneumothorax. Another ICD was therefore inserted and a radiograph (figure 2) was obtained to check location. We were surprised to see enlargement of the pneumothorax and significant left shift of the mediastinum suggesting the development of a right tension pneumothorax. We considered that the ICD might not be functioning, however, this seemed unlikely as the water level was swinging with respiration and bubbles were observed on coughing. A large, unidirectional air-leak into the hemithorax could exceed the drainage capacity of the ICD at low intrathoracic pressure. This would allow a degree of air accumulation and an increase in intrathoracic pressure (until equilibrium was reached) sufficient to cause mediastinal shift. The three-sided dressings should have prevented continued external air-leak but they may not have stuck properly or could have become dislodged. In support of this theory, wound closure in two layers resulted in resolution of the pneumothorax.