Computers in clinical practice: screening renal patients for abnormal biochemistry and malnutrition

Develop and compare a computer program (CP) and a screening tool (ST) to determine the best method of identifying patients undergoing hemodialysis (HD) who are at risk of malnutrition. Investigate the benefits of using the CP to screen biochemical test results of patients undergoing HD, continuous ambulatory peritoneal dialysis (CAPD), nephrology patients, and transplant recipients for abnormal levels, such as hyperkalemia.

The CP was designed by using the program Proton (Clinical Computing Clinical Information Systems, Middlesex, England). Proton can automatically download biochemical results from pathology, making it possible to generate a list of patients with results outside a desired biochemical range in accordance with national renal standards for adult patients. Biochemical measures of nutritional status were used to define malnutrition as 2 or more results outside of these parameters: 10% weight loss; Kt/V < 1.1; predialysis urea, <20 mmol/L; phosphate, <0.75 mmol/L; and potassium, <3.3 mmol/L. One hundred eighty-four HD patients were incidentally screened for their risk of malnutrition by using both the CP and the ST.

Richard Bright Renal Unit, Bristol, England, and 4 satellite HD units in Southwest England.

Three thousand five renal outpatients, including 468 patients with diabetes, had blood test results screened by the CP for abnormal levels. This included 235 HD patients (unit A, n = 32; unit B, n = 58; unit C, n = 70; Unit D, n = 24; home HD unit, n = 51), 88 CAPD patients, 416 transplant recipients, and 2,266 nephrology patients.

The CP and the ST were compared with standardized dietetic assessments (SDAs) for validity. In the clinic setting, the length of time taken to review biochemical test results was measured before and after implementation of the CP.

The CP identified 36% of HD patients at risk of malnutrition, compared with 20% by the ST and 42% by SDA. However, only 57% of the STs were completed. The CP found 42% of transplant recipients and 92% of nephrology patients have glycosylatid hemoglobin levels >7, and 16% of HD patients have fluid weight gains >3 kg on 4 or more occasions in a month.

Using the present parameters, the CP is not sensitive enough to correctly identify all HD patients at risk of malnutrition. Screening for serum cholesterol, prealbumin, protein equivalent of total nitrogen appearance, and C-reactive protein levels should be incorporated into the CP to compare it with a simple, inexpensive, and reproducible screening tool, such as subjective global assessment, to identify malnutrition in patients undergoing dialysis. The CP improves time management and rationalization of dietetic activity by screening abnormal biochemistry levels. Renal dietitians are urged to investigate the practicalities and the benefits of computers in clinical practice because early identification of malnutrition in patients allows dietitians to work in a more proactive manner.