Culture of the irrigating fluid of the epidural space obtained during chronic epidural catheterization

The most serious complication during long-term epidural catheterization is epidural infection. Bacterial culture of the irrigating fluid of epidural space was carried out periodically in 39 patients in whom epidural catheters were inserted for a long period of time. Eight (17%) of 47 samples of epidural irrigating fluid were contaminated by the normal skin flora. All of these cases were accompanied with epidural contamination by the same organisms. No significant correlation was found between clinical signs of infection (low grade fever, leucocytosis and localized infective signs at the puncture site) and the contamination of the epidural irrigating fluid or that of the epidural catheter. When epidural irrigating fluid was contaminated, the epidural catheter was removed immediately and the patient was treated by antibiotics. None of the patients had epidural abscess or neurological deficit. In conclusion, bacterial culture of epidural irrigating fluid is valuable for the early diagnosis of epidural infection during long-term epidural catheterization.