Cuena BR, Maciá MMA, López RR, Martín MMP

Language: Spanish
References: 14
Page: 306-312
PDF size: 74.04 Kb.

ABSTRACT

Purpose: To evaluate three methods for digoxin dose adjustment in aged patients. Methods: We determined the plasma digoxin levels that would be atained in 47 consecutive old patients with doses adjusted to the creatinin clearance (Clc) by means of three mathematical functions. Results: Age: 79.1 ± 6.1 years of age; Clc: 0.77 ± 0.24 mL/kg of lean body weight and minute. Once the dose has been fitted to the digoxin pharmacokinetic parameters described in the bibliography, the drug levels would oscillate between 0.8 and 2.0 ng/mL in 85.1% of the patients, with a 95% confidence interval (95% CI) from 72.3% to 92.6%; in 0.0% of the patients the levels would be greater than 2 ng/mL (95% IC: 0.0% to 7.6%). The precision and the bias would be 0.40 ng/mL (95% IC: 0.33 to 0.46 ng/mL) and –0.08 ng/m (95% IC: -0.19 to 0.04 ng/mL), respectively. The drug level would not be associated with the Clc (coefficient of Clc in the regression line: -0.0003; P › 0.9). The results would be worse with the others two mathematical functions. Conclussion: The first of the above adjustment methods would lead to good results if digoxin has not been prescripted in order to control the cardiac frequency in the setting of auricular fibrilation.

REFERENCES

1. Cuena Boy R: Evaluación de métodos para la elección de la dosis inicial de digoxina en ancianos. Farm Clín 1998; 15: 10-20.

2. Jellife RW: An improved method of digoxin therapy. Ann Intern Med 1968; 69: 703-717.

3. Sheiner LB, Benet LZ, Pagliaro, LA: A standard approach to compiling clinical pharmacokinetic data. J Pharmacokinet Biopharm 1981; 9: 59-127.

4. Sheiner LB, Rosenberg BG, Marathe VV: Estimation of population characteristics of pharmacokinetic parameters from routine clinical data. J Pharmacokinet Biopharm 1977; 5: 445-479.

5. Anónimo. Dosificación de la digoxina. Boletín del Centro Regional de Farmacovigilancia de Castilla-La Mancha 1995; 6: 10-12.

6. Cockroft DW, Gault MH: Prediction of creatinine clearance from serum creatinine. Nephron 1976; 16: 31-41.

7. Devine BJ: Gentamicin therapy. Drug Intel Clin Pharm 1974; 8: 650-655.

8. Bresnahan JF: Understanding and using data on serum digoxin concentrations in clinical practice: a case study. En: Moyer TP, Boeckx RL. eds. Applied therapeutic drug monitoring. Vol. 2: review and case studies. Washington: The American Association for Clinical Chemistry, 1984. p. 97-99.

9. Armijo JA: Leyes generales y aplicaciones de la farmacocinética. En: Flórez J, Armijo A, Mediavilla A. eds. Farmacología humana. 2ª Ed. Barcelona: Ediciones Científicas y Técnicas, S. A., 1992. p. 75-97.

10. Sheiner LB, Beal SL: Some suggestions for measuring predictive performance. Pharmacokinetic Biopharm 1981; 9: 503-512.

11. Carruthers SG, Kelly JG, McDevitt DG: Plasma digoxin concentrations In patients on admission to hospital. Br Heart J 1974; 36: 707-712.

12. Beller GA, Smith TW, Abelmann WH, Haber E, Hood WB: Digitalis intoxication: a prospective clinical study with serum level correlations. N Engl J Med 1971; 284: 989-997.

13. Fogelman AM, La Mont JT, Finkelstein S, Rado E, Pearce ML: Fallibility of plasma-digoxin in differentiating toxic from non-toxic patients. Lancet 1971; 2: 727-729.

14. Nolan L, Kenny R, O´Malley: The need for reassessment of digoxin prescribing for the elderly. Br J Clin Pharmacol 1989; 27: 367-370.