Major complications after percutaneous nephrostomy-lessons from a department audit.

AIM: To audit the performance of our percutaneous nephrostomy service by comparing the major complication rate with the standards recommended by the Society of Cardiovascular and Interventional Radiology and the American College of Radiology: major haemorrhage in <4%, and septic shock in <4%. Secondary aims were to identify common sources of errors for quality improvement measures.
METHODS: Major complications sustained between January 1997-December 2002 were identified. All cases had been carried out by the interventional radiology service of a large teaching hospital with the assistance of a nurse and radiographer, under fluoroscopic and ultrasound guidance using a Seldinger technique. Existing department protocols specified pre-procedure antibiotics for suspected infected cases and normal coagulation studies. From records and review of case notes pertinent clinical/procedural details and eventual outcome were assessed. The following were particularly noted: adherence to protocols, clinical status at time of procedure, delay in referral, complication sustained, signs of infection or coagulopathy, timing of procedure (in versus out of hours), level of operator and technical faults.
RESULTS: Ten of 318 (3.1%) cases sustained a major complication: five had sepsis alone, two haemorrhage (one with sepsis as well) and three patients had a major pelvic injury (one with sepsis as well). Thus the major sepsis and haemorrhage rates were 2.2 and 0.6%, and were within the recommended threshold limits but proportionately more complications occurred out of hours: six of 105 (5.7%) versus four of 312 (1.8%; p=0.087). Sepsis was the most serious complication and may have contributed to the death of two patients. On individual case analysis, failed instrumentation with delay to definitive renal drainage was a common factor with sepsis; but the following were contributory factors in one or more cases: omitted antibiotics (in three of 10; two became septic), technical factors in four cases [medial renal puncture (n=1), damage due to fascial dilator (n=1) or peelaway sheath (n=2)] and delay in diagnosis/therapy (of 1-8 days, in six of 10 cases of whom four out of six became septic). One pelvic injury required surgical correction (contributory factor-faulty use of peelaway sheath). Patients with haemorrhage settled with prolonged tube drainage alone.
CONCLUSION: An adequately staffed percutaneous nephrostomy service can perform within published clinical standards. Best practice factors identified were: attention to agreed protocols and algorithms, pre-procedure antibiotics, careful renal puncture and care with use of dilators/peelaway sheaths, but the paramount finding was that sepsis was the most serious complication, contributing to death (two of 10 in this study) or a significant increase in the level of care required. The risk is greatest after failed instrumentation (retrograde ureteral stent or percutaneous nephrostomy insertion) and particularly if there is a further delay before establishment of renal drainage. A close working relationship between interventional radiologists and urologists is crucial.