Study objective: To compare success rates, complications, and efficiency of suprapubic bladder aspiration with urethral catheterization in ill infants.
Design: Prospective, randomized clinical study.
Setting: The pediatric emergency department at the University of Mississippi Medical Center in Jackson.
Participants: Convenience sample of infants under 6 months of age requiring an uncontaminated urine specimen for the evaluation of febrile illness, suspected urinary tract infection, or sepsis. Infants with wet diapers were excluded.
Interventions: Patients were randomized to undergo timed suprapubic bladder aspiration (performed by a physician and a nurse) or urethral catheterization (performed by two nurses). If suprapubic bladder aspiration was unsuccessful, urethral catheterization was performed immediately and the bladder was drained; emptying volume was recorded. All patients had a next-void "bag" urinalysis performed for post-procedure hematuria.
Results: Fifty patients underwent primary suprapubic bladder aspiration. The success rate (defined by obtaining at least 2 mL of urine) was 46%. Mean +/- SD time per successful suprapubic bladder aspiration was 16.73 +/- 7.73 seconds. Fifty patients underwent primary urethral catheterization. The success rate was 100%; the mean time required was 80.70 +/- 46.52 seconds. After failed suprapubic bladder aspiration, urethral catheterization was 100% successful, with a mean draining volume of 2.95 +/- 2.38 mL. No immediate problems were identified among any instrumented patients; later complications (next-void hematuria after either procedure, other visceral injury with suprapubic bladder aspiration) were not detected.
Conclusion: Both suprapubic bladder aspiration and urethral catheterization afford the emergency physician low-risk access to uncontaminated urine in ill infants. Suprapubic bladder aspiration is less efficient in that it requires physician participation and failure rates are higher. These data suggest that successful suprapubic bladder aspiration is primarily dependent on the volume of urine in the bladder; thus, in the ill or febrile ED infant who may be dehydrated, the likelihood of success decreases. The authors recommend that ED nursing and physician staff become comfortable with performing urethral catheterization on infants.