In a previous report from this institution, 21% of splenectomies performed between 1957 and 1967 were for iatrogenic injury to the spleen. In the present study, encompassing the years 1971 to 1987, the frequency of iatrogenic splenic injury was reduced to 9% (134 of 1,557 splenectomies). However, there has been no evidence of a progressive decrease in accidental splenic injury from 1971 to 1987. Although the number of injuries related to operations on the stomach or repair of hiatus hernia have declined somewhat in the past decade, the incidence of splenic injuries secondary to colectomy and nephrectomy has not changed appreciably, and injuries linked to complex operations on the aorta and its branches (19 cases) have increased. No evidence could be found that morbidity was increased if the splenic injury is promptly recognized and managed by splenectomy. However, 13 of these 134 patients required reoperation for control of continued bleeding from unrecognized iatrogenic splenic trauma. Constant awareness of the continued prevalence of this operative complication and the mechanisms by which it is produced should enable surgeons to lessen its frequency and potential sequelae., Iatrogenic injury is damage to the body caused by a physician or surgeon. During abdominal operations, such injuries can occur to the spleen, particularly when procedures are performed on the stomach, kidney, or aorta (the large artery carrying blood to the lower part of the body). Although surgeons are well aware of the possibility of this complication, the issue has not been recently assessed. To this end, a review was conducted of the records of 1,557 splenectomies (removal of the spleen) performed between 1971 and 1987. Of these, 9 percent (134) had been performed due to iatrogenic injury to the spleen; in the other 91 percent, the spleen was removed for other reasons. A partial breakdown of the operations during which the spleen was inadvertently damaged was: gastric procedures, 32 patients; nephrectomy (removal of a kidney), 28 patients; colectomy (removal of the colon), 24 patients; repair of hiatus hernia (protrusion of part of the stomach above the diaphragm), 14 patients; and resection of an aortic aneurysm (removal of a dilated part of the aortic wall), 11 patients. In many patients, extensive cancer in the region where the surgeon worked was associated with iatrogenic injury. Thirteen patients for whom splenic trauma was not noted during the original surgical procedure required re-operation to control bleeding. The consequences of damage to the spleen have been a subject of intense debate for decades; a review of relevant articles is provided. The complications are certainly more serious if damage to the spleen goes unrecognized and internal bleeding is allowed to continue. The importance of proper preventive and corrective measures is emphasized. (Consumer Summary produced by Reliance Medical Information, Inc.)