Critical Illness, Fluid Overload
Conditions
Keywords
Fluid Balance, Body Weight Change, Critical Illness
Brief summary
Positive fluid status has been consistently associated with worse prognosis in critically ill adult patients.However, observational studies showed poor agreement between fluid balance and body weight changes. The objective of the study is to compare the measurements of FB and BW over time and to assess correlation with ICU mortality.
Detailed description
Positive fluid status has been consistently associated with worse prognosis in critically ill adult patients. Daily and cumulative fluid balance (FB) is a routine nursing activity in intensive care unit (ICU). In view of the potential for errors in the calculation of FB totals and the problem of accounting for insensible fluid losses, measurement of body weight (BW) changes is an alternative non-invasive method commonly used for estimating body fluid status. Its accuracy over FB assumes a one kilogram change in BW equates to a one liter gain or loss in body fluid volume. However, observational studies showed poor agreement between those measurements, particularly among individuals staying more than a week in ICU possibly due to muscle and fat loss as well as bone demineralization. The objective of the study is to compare the measurements of FB and BW over time and to assess correlation with ICU mortality.
Interventions
OTHERRegular critical care
Clinical demographic data, daily and cumulative FB (input minus output) with and without insensible fluid losses, and daily and total BW changes are recorded, as well as survival outcome.
Sponsors
Hospital de Clinicas de Porto Alegre
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Individuals aged \>18 years-old admitted to ICU; * Expected length of ICU stay superior to 24 hours.
Exclusion criteria
* Individuals receiving oral diet; * Actual body weight superior to 227kgs or 501lb.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between daily fluid balance (difference between fluid input and output during 24 hours) and the change on daily weight | At midnight every 24 hours up to patient's ICU discharge or up to 6 months, whichever comes first. | Correlation between daily fluid balance and weight change (Bland-Altman agreement test) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between cumulative fluid balance and total weight change | Last day of each patient's ICU hospitalization, up to 6 months | Correlation between cumulative fluid balance and total weight change (Bland-Altman) |
| Discriminative power of fluid balance in predicting ICU mortality | Through study completion, up to 6 months | Area under ROC curve for fluid balance (L). ICU mortality as reference variable. |
| Discriminative power of body weight changes in predicting ICU mortality | Through study completion, up to 6 months | Area under ROC curve for body weight change (kg). ICU mortality as reference variable. |
Countries
Brazil
Outcome results
None listed