Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support
ii.
Dosage of hydrochloric acid:
| (a) | Chloride deficit (Arch Surg 1975;110:819-21): |
|---|
Dose (mEq) = 0.2 L/kg x Wt (kg) x (103 β serum chloride)
| (b) | Bicarbonate excess (J Am Soc Nephrol 2000;11:369-75): |
|---|
Dose (mEq) = 0.5 L/kg x Wt (kg) x (serum bicarbonate -24)
| (c) | A practical approach is to administer one-half of the calculated dose over 12 hours and |
|---|
repeat the arterial blood gas at 6 and 12 hours with readjustment of infusion rate, if
necessary. Discontinue the infusion when the pH is less than 7.5.
Treatment β Saline-unresponsive alkalosis: Treat underlying cause (if possible).
Exogenous corticosteroids β Decrease dose or use drug with less mineralocorticoid effect.
Excessive alkali intake β Alter regimen.
Profound hypokalemia (serum potassium less than 3 mEq/L) β Aggressive potassium
supplementation
| d. | Rare causes: Endogenous mineralocorticoid excess (Bartter or Gitelman syndrome) β |
|---|
Spironolactone, amiloride, or triamterene; consider surgery
Liddle syndrome: Amiloride or triamterene
Nutrition Risk Assessment
βDetermination of Nutrition Riskβ β recommended by 2016 SCCM/ASPEN guidelines to guide
the approach to nutrition support therapy in critically ill patients. High nutrition risk identifies
those patients most likely to benefit from early EN therapy. (JPEN J Parenter Enteral Nutr 2016;40:
159-211)
Nutritional Risk Screening (NRS 2002; Clin Nutr 2003;22:321-36)
Nutritional Status
Severity of Disease
Score
Score
Normal Nutritional Status
Normal nutritional requirements
Wt loss > 5% in 3 months or food intake < 50%
to 70% of normal in preceding week
Hip fracture, chronic patients with acute
complications (e.g., cirrhosis, COPD, diabetes,
oncology)
Wt loss > 5% in 2 months or body mass index
(BMI) 18.5 to 20.5 + impaired general condi-
tion or food intake < 25% to 50% of normal in
preceding week
Major abdominal surgery, stroke, pneumonia,
hematologic malignancy
Wt loss > 5% in 1 month (~15% in 3 months) or
BMI < 18.5 + impaired general condition or food
intake 0 to 25% of normal in preceding week
Head injury, bone marrow transplantation,
critically ill ICU patient
Add the two scores (nutritional status + severity of disease). If age 70 years or greater, add 1 to total score. If age-
corrected score 3 or greater, start nutritional support.