RT Journal Article SR Electronic T1 Chest wall thickness may limit adequate drainage of tension pneumothorax by needle thoracocentesis. JF Journal of Accident & Emergency Medicine JO Arch Emerg Med FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 426 OP 427 DO 10.1136/emj.13.6.426 VO 13 IS 6 A1 S Britten A1 S H Palmer YR 1996 UL http://emj.bmj.com/content/13/6/426.abstract AB Tension pneumothorax in a large man was inadequately drained by needle thoracocentesis with a 4.5 cm cannula. Unsuccessful needle thoracocentesis of a clinical tension pneumothorax in a large patient should be followed immediately by chest drain insertion, without local anaesthetic, as dictated by clinical urgency. If the clinical situation is still not improved other diagnoses should be considered.