Table 1.
Authors | Publication Date | N, CSW/Total | CSW, % | Assessment of ECF/IVF Volume |
---|---|---|---|---|
Nelson et al. (1) | 1981 | 10/12 | 81 | RBC mass (chromium-51 erythrocytes),a plasma volume (isotope dilution),b and total blood volumea |
Wijdicks et al. (2) | 1985 | 6/9 | 67 | >10% decrease in plasma volume (isotope dilution),b increased BUN,c and decreased body weightd |
Sivakumar et al. (4) | 1994 | 17/18 | 94 | Decreased hematocrite and total blood volumea and/or low CVPf |
Sherlock et al. (5) | 2006 | 4/62 | 6.5 | Low CVPf with ongoing natriuresis and diuresis |
Kao et al. (6) | 2009 | 11/48 | 22.9 | Daily fluid balance and response to isotonic NaCl infusiong |
Hannon et al. (7) | 2014 | 0/49 | 0 | Daily clinical assessment of ECFV, increased BUN,c and low CVPf |
CSW, cerebral salt wasting; ECF, extracellular fluid; IVF, intravascular fluid; RBC, red blood cell; CVP, central venous pressure; ECFV, extracellular fluid volume.
Decreased RBC mass and total blood volume are indicators of blood loss but not ECF volume depletion.
Decreased plasma volume by isotope dilution may indicate ECF/IVF volume depletion but also can be due to venoconstriction with intact ECF and IVF volumes.
BUN may be increased by ECF volume contraction but also by other causes (e.g., gastrointestinal bleeding, glucocorticoid administration, or catabolic state).
Decreased body weight is typical in sick hospitalized patients, and it is an unreliable indicator of ECF/IVF volume status.
Decreased hematocrit may indicate blood loss or dilution from water retention but not ECF/IVF volume depletion, in which case the hematocrit would be increased.
Low CVP may indicate ECF/IVF volume depletion but can be influenced by many other factors, including vasodilation and mode of measurement.
Increase in serum [Na+] in response to isotonic saline infusion is generally indicative of ECF volume depletion, but it may also occur in conjunction with spontaneous resolution of transient syndrome of inappropriate antidiuretic hormone secretion.