Risk Factors for Wound Infection Following Caesarean Section


Department of Obstetrics and Gynaecology, Middlemore Hospital, Auckland, New Zealand.


EDITORIAL COMMENT: This paper has a special message for readers concerned about post-Caesarean section wound infections, because of the careful documentation after the patients were discharged from hospital. We all have cared for women who telephone to tell us about a discharge from the Caesarean wound after they have returned home. We advise these women to return for examination if febrile, or if the wound is painful, or if there is a purulent discharge from it. Usually the problem is managed by the woman dressing the area of discharge without any but this verbal consultation. At the postnatal visit the wound is healed but the scar may signal the area of the problem. How important are minor wound infections as defined in this study? The patient and the surgeon would of course prefer to avoid these complications, but it is the major wound infections, with or without disruption, that really matter, and which hopefully have a reduced incidence when intraoperative antibiotic administration is practised. In addition to complete documentation we also require grading of wound infections in terms of risk to life and time spent in hospital.

Response to editorial comment from authors: Although the majority of wound infections diagnosed after discharge from hospital were not ‘major’, with only 2 patients requiring readmission, there was significant morbidity amongst this group and considerable cost to the health services. General practitioners saw and treated 12 of the 30 (40%), and there was also an increase in the workload for the Home Care Midwifery service with 49% of all visits to Caesarean section women being to the 30% that were infected (figure 1). Thus, these nonmajor wound infections would appear to be important for both the woman with her delay in returning to normal activities, and for our already overstretched Home Care Midwives, with an increase in demand for their services.

Summary: A prospective study was performed between April 1,1991 and April 30,1992 to determine factors involved in the development of post-Caesarean section wound infection. During this period there were 4,857 deliveries, 428 by Caesarean section (8.8%). Complete data were available on 328 (76.6%) patients. Wound infection occurred in 25.3% of women and was confirmed by positive bacteriology in 77.1%; 36% of wound infections were diagnosed following the patients' discharge from hospital. A negative correlation was found between maternal age and development of wound infection up to age 40 (p = 0.03). Maternal weight was a highly significant indicator of subsequent wound infection development (p = 0.0001), the relationship between increasing maternal weight and infection appearing linear. Antibiotic prophylaxis was found to be the most significant protective factor (p = 0.0007) in the reduction of postoperative wound infection. This relationship was independent of maternal weight.