[Hypophosphatemia in parenteral nutrition: prevention and associated risks factors].
OBJECTIVE
To determine the incidence of hypophosphatemia in parenterally fed patients, the phosphate amount necessary to prevent this complication and associated risks factors.


METHODS
Observational study, not controlled, in a third level hospital.


METHODS
In-patients with parenteral nutrition with at least a complete laboratory work-up.


METHODS
For a complete year, days on parenteral nutrition, administered phosphate and plasmatic ionised calcium levels, y-glutamiltranspeptidase, glucose, phosphate, pre-albumin, urea, and leukocytes were recorded. A multiple stepwise regression analysis and logistic regression are used for data analysis.


RESULTS
Eight hundred and twenty seven determinations, corresponding to 401 patients, were included. Significant variables (p < 0.05) were: administered phosphate and ionised calcium serum levels, glucose, pre-albumin, and urea; regression coefficients were 0.004 (95%CI: 0.002 to 0.006), -0.156 (95%CI: -0.270 to 0.037), -0.014 (95%IC: -0.022 to 0.009), 0.005 (95%CI: 0.002 to 0.009) and 0.019 (95%CI: 0.016 to 0.022), respectively; the constant was 1.0735 (95%CI: 0.939 to 1.2079). The risk for developing hypophosphatemia decreased from 0.65 (95%CI: 0.33 to 1.26) to 0.16 (95%CI: 0.078 to 0.35) when administered phosphate varied from the span 7.5-17.5 mmol to values higher than 27.5 mmol.


CONCLUSIONS
It is necessary to routinely supplement nutrition with phosphate since its content in commercially available lipidic emulsions is not sufficient to prevent hypophosphatemia in the majority of patients with parenteral nutrition. Phosphate intake must be sufficient to restore the intracellular phosphate deficit and to compensate for the plasmatic phosphate fall, with special attention to poorly nourished, hyperglycaemic or with renal failure patients. Phosphate intakes around 27-37 mmol dramatically decrease the incidence of hypophosphatemia in studied patients, with no recorded cases of severe hypophosphatemia.
Llop Talaverón
J M
JM
Servicio de Farmacia. Hospital Universitari de Bellvitge. L'Hospitalet de Llobregat. Barcelona. josep.llop@csub.scs.es
Comas Sugrañes
D
D
Badía Tahull
M B
MB
Sáez Fernández
A
A
Jódar Masanés
R
R
Gómez Sáez
J M
JM
D001774:Blood Chemical Analysis; D002130:Calcium Phosphates / Q000008:administration & dosage; D005260:Female; D006801:Humans; D017674:Hypophosphatemia / Q000097:blood / Q000209:etiology* / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D010288:Parenteral Nutrition / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors
D002130:Calcium Phosphates