Premium
Effects of Catheter Size on Urodynamic Measurements in Men Undergoing Elective Prostatectomy
Author(s) -
NEAL D. E.,
RAO C. V. S.,
STYLES ROSEMARY A.,
NG T.,
RAMSDEN P. D.
Publication year - 1987
Publication title -
british journal of urology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.773
H-Index - 148
eISSN - 1464-410X
pISSN - 0007-1331
DOI - 10.1111/j.1464-410x.1987.tb09136.x
Subject(s) - catheter , medicine , urology , prostatectomy , urodynamic studies , anesthesia , surgery , prostate , cancer , urinary incontinence
Summary— Thirty men undergoing prostatectomy for symptoms of bladder outflow obstruction and low measured maximum flow rates (20 before and 10 after operation) were studied by means of urodynamic investigation. Paired studies were performed on each patient using a large catheter assembly (4 and 10 F) and a small catheter assembly (epidural line, outside diameter 1.1 mm). The order in which the studies were performed was varied randomly. Detrusor pressure at maximum flow rate was significantly greater in the large catheter study (73 ±30 cm H 2 O) than in the small catheter study (65 ±27 cm H 2 O; P < 0.003). The maximum flow rate was significantly smaller in the large catheter study (8.9 ± 9.5 ml/s) than in the small catheter study (12±7 ml/s; P <0.001). The increase in detrusor pressure at maximum flow that was noted during the large catheter study was confirmed in the 20 men who were studied before prostatectomy (mean increase 11 ± 11 cm H 2 O; P <0.001) but no difference was found between the two methods in the 10 men studied after prostatectomy (50 ± 19 cm H 2 O and 49± 15 cm H 2 O). Using a large catheter assembly to perform urodynamic investigations has the advantage that repeated studies can be performed without recatheterisation, but it has the disadvantage of producing a small increase in detrusor pressure at maximum flow in men with symptoms of bladder outflow obstruction. Few errors in diagnosis should result, however, if laboratories using such catheters are aware of this effect and establish their own limit of normal for voiding pressures.