Reliability of intrabladder pressure measurement in intensive care.
BACKGROUND
The reliability of intrabladder pressure measurements obtained in nonsupine patients is unknown.


OBJECTIVE
To investigate the reliability of measurements of intrabladder pressure obtained with 30 degrees head-of-bed elevation.


METHODS
With patients supine, 30 degrees head-of-bed elevation, and instillation of 0 and 25 mL physiological saline, intrabladder pressure was measured in 10 patients: twice by one nurse to assess intraobserver reliability and once by a different nurse to assess interobserver reliability. Data were analyzed by using paired t tests, Pearson correlation, and Bland-Altman analysis.


RESULTS
For intraobserver reliability, measurements obtained with no instillation (mean difference, -1.8; 95% confidence interval [CI], -4.9 to 1.3; P = .22) and with instillation of 25 mL (mean difference, -0.6; 95% CI, -1.8 to 0.6; P = .28) did not differ significantly. Pearson r values were 0.74 and 0.81, respectively. Estimated Bland-Altman bias and limits of agreements were -1.8 and -10.3 to 6.7 mm Hg and -0.6 and -3.82 to 2.62 mm Hg, respectively. For interobserver reliability, measurements obtained with no instillation (mean difference, 1.0; 95% CI, -2.2 to 4.2; P = .49) and with instillation of 25 mL (mean difference, -0.7; 95% CI, -2.45 to 1.05; P = .39) did not differ significantly. Pearson r values were 0.78 and 0.82, respectively. Estimated Bland-Altman bias and limits of agreement were 1.0 and -7.76 to 9.76 mm Hg and -0.7 and -5.5 to 4.0 mm Hg, respectively.


CONCLUSIONS
Reliability of intrabladder pressure measurements obtained with 30 degrees head-of-bed elevation is strong.
Shuster
Melanie Horbal
MH
West Penn Allegheny Health System, Allegheny Center for Digestive Health, Pittsburgh, Pennsylvania, USA. mshuste1@wpahs.org
Haines
Tammy
T
Sekula
L Kathleen
LK
Kern
John
J
Vazquez
Jorge A
JA
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011312:Pressure; D011446:Prospective Studies; D015203:Reproducibility of Results; D016683:Supine Position; D001743:Urinary Bladder / Q000503:physiopathology*