Prospective trial of the six hour rule in stab wounds of the chest.

Stab wounds of the chest may be associated with a spectrum of injuries ranging from the lethal to the insignificant. The management of asymptomatic patients with stab wounds of the chest is controversial. The results of previous reports have asserted that asymptomatic patients with stab wounds of the chest do not have delayed complications develop if roentgenograms of the chest taken six hours after the injury are normal. This "rule" has not been validated. A three year, prospective study of patients with stab wounds of the chest was done. Patients were excluded from the study if they had symptoms on arrival, evidence of physiologic derangement caused by intrathoracic injury, wounds near the subclavian vessels or precordial wounds. Patients with lower thoracic stab wounds were evaluated by diagnostic peritoneal lavage. If findings from lavage were negative, the patients were included in the study. One hundred and five patients met the criteria for inclusion in the study group. All of the patients were hospitalized and examined serially. All had roentgenograms of the chest performed at admission, at six hours and at 24 hours. Four patients had a pneumothorax or hemothorax develop between the time of admission and six hours of hospitalization. In the remaining 101 patients, none had a pneumothorax or hemothorax between six and 24 hours. No patient asymptomatic on admission had a tension pneumothorax develop later. No patient had delayed evidence of abdominal injury. An asymptomatic patient with a stab wound of the chest that is not precordial, not in proximity to the subclavian artery and not suspected of diaphragmatic penetration should be serially examined and have a follow-up roentgenogram of the chest at six hours. If the patient remains asymptomatic and the six hour film is normal, delayed complications are rarely, if ever, encountered and the patient does not require further studies or hospitalization. The six hour rule for stab wounds of the chest is valid.