TY - JOUR
T1 - Estimation of fluid status changes in critically ill patients: fluid balance chart or electronic bed weight?
AU - Schneider, Antoine
AU - Baldwin, Ian
AU - Freitag, Elke
AU - Glassford, Neil
AU - Bellomo, Rinaldo
PY - 2012
Y1 - 2012
N2 - Purpose: Monitoring of fluid balance (FB) can be achieved by subtracting recorded fluid output from
input or by measuring changes in body weight (BW). The latter approach is difficult in the critically ill.
Recently, hospital beds have become available with the ability to directly weigh patients in the intensive
care unit (ICU) patients directly. We sought to compare FB estimates obtained by these 2 methods in a
cohort of critically ill patients.
Materials and Methods: Between November 2010 and May 2011, all patients admitted in our ICU for
more than 2 consecutive days and nursed on a Hill-Rom (Batesville, Ind) Total Care bed were weighed
daily at midnight hours. Fluids charting was done by electronic spreadsheet with automated 24 hours
calculation. Differences in BW and FB between 2 consecutive days were compared using correlation
and Bland-Altman analysis. Corrections for unmeasured fluids losses were performed using a
predetermined formula based on peak temperature and intubation status.
Results: We obtained complete data in 160 (31 ) of 504 admissions exceeding 2 days (153 patients)
resulting in 435 data points. The change inBWover 24 hours and FB for the same period was only weakly
correlated before (r = 0.34; P b .001; Fig. 1) or after correction for insensible fluid losses (r = 0.34; P b
.001). On Bland-Altman plot, the mean bias was small (0.07 kg), but the 95 limits of agreement, very
large (-5.8 and 6.0 kg). The lack of agreement increased with the magnitude of the changes.
Conclusion: Obtaining daily weights in ICU patients proved difficult. Compliance was poor. The
correlation between changes in BWs and FB was weak. Further studies are required to establish if accurate
and reproducible daily weighing of ICU patients is feasible.
AB - Purpose: Monitoring of fluid balance (FB) can be achieved by subtracting recorded fluid output from
input or by measuring changes in body weight (BW). The latter approach is difficult in the critically ill.
Recently, hospital beds have become available with the ability to directly weigh patients in the intensive
care unit (ICU) patients directly. We sought to compare FB estimates obtained by these 2 methods in a
cohort of critically ill patients.
Materials and Methods: Between November 2010 and May 2011, all patients admitted in our ICU for
more than 2 consecutive days and nursed on a Hill-Rom (Batesville, Ind) Total Care bed were weighed
daily at midnight hours. Fluids charting was done by electronic spreadsheet with automated 24 hours
calculation. Differences in BW and FB between 2 consecutive days were compared using correlation
and Bland-Altman analysis. Corrections for unmeasured fluids losses were performed using a
predetermined formula based on peak temperature and intubation status.
Results: We obtained complete data in 160 (31 ) of 504 admissions exceeding 2 days (153 patients)
resulting in 435 data points. The change inBWover 24 hours and FB for the same period was only weakly
correlated before (r = 0.34; P b .001; Fig. 1) or after correction for insensible fluid losses (r = 0.34; P b
.001). On Bland-Altman plot, the mean bias was small (0.07 kg), but the 95 limits of agreement, very
large (-5.8 and 6.0 kg). The lack of agreement increased with the magnitude of the changes.
Conclusion: Obtaining daily weights in ICU patients proved difficult. Compliance was poor. The
correlation between changes in BWs and FB was weak. Further studies are required to establish if accurate
and reproducible daily weighing of ICU patients is feasible.
UR - http://www.sciencedirect.com/science/article/pii/S0883944112000032
U2 - 10.1016/j.jcrc.2011.12.017
DO - 10.1016/j.jcrc.2011.12.017
M3 - Article
SN - 0883-9441
VL - 27
SP - e7 - e12
JO - Journal of Critical Care
JF - Journal of Critical Care
IS - 6
M1 - 754
ER -