The accuracy of clinical assessment of bladder volume.

Abstract

To determine the usefulness of physical examination in detecting elevated bladder volume. A blinded study of clinical examination by physicians to detect elevated bladder volumes compared with a criterion standard (ultrasonic bladder volume measurement). Outpatient department of a general hospital in New Zealand. Sixteen healthy adult volunteers (age range, 21-37 y; body mass index range, 22.9-37.2 kg/m(2)) and 8 qualified resident physicians with 2 to 6 years of clinical experience. Elevated bladder volumes were achieved by randomly allocating the volunteers to void or not to void before the clinical examination. Clinical examination of the abdomen by abdominal palpation and suprapubic percussion, compared with portable ultrasound findings, to determine whether a healthy adult has a full bladder. For bladder volumes of 400 to 600 mL, physical examination to detect a full bladder was 81% sensitive (95% confidence interval [CI], 54-96), 50% specific (95% CI, 39-68), and 55% accurate (95% CI, 45-65). The likelihood ratio for a positive finding on physical examination was 1.62 (95% CI, 1.17-2.24). Physical examination of the abdomen by relatively junior physicians is unreliable in detecting bladder volumes between 400 and 600 mL in healthy volunteers.