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D R Conti

Publications and source records attributed to D R Conti.

7 recordsLinked to original sources
PubMed1979

Clinical pharmacokinetics of procainamide infusions in relation to acetylator phenotype.

The pharmacokinetics of procainamide was determined in 21 lidocaine-resistant patients who received the drug according to a pharmacokinetically designed double-infusion technique. Thirteen patients were phenotyped as slow acetylators, seven as fast, and one as intermediate. The total body clearances (ClT) of PA in slow and fast acetylators were 22.6 and 34.8 liters/hr, respectively. The fraction of PA cleared by the formation of NAPA in the corresponding acetylator group was 0.2 and 0.4. Renal impairment affected the pharmacokinetics of PA more profoundly as the ClT's of PA in patients with and without renal impairment were 17.9 and 31.2 liters/hr, respectively. None of the calculated volumes of distribution was affected by acetylator phenotype or renal impairment. These data identify the contribution of at least two of the major factors accounting for variability in PA disposition in patients undergoing therapy.

Acetylation↗
PubMed1979

Safety and efficacy of procainamide infusions.

Thirty-four patients who were resistant to conventional doses of lidocaine received procainamide intravenously according to a pharmacokinetically designed two infusion technique. A mean peak serum concentration of 7.1 mg/liter was achieved with an average loading dose of 989 mg administered over 1 hour. A mean steady state serum concentration of procainamide of 6.5 mg/liter was achieved with a mean dose of 64.4 mg/kg body weight for the first 24 hours of treatment. Dose, renal impairment, the degree of congestive heart failure and acetylator status influenced the steady state serum concentration of procainamide. Dangerous ventricular arrhythmias were abolished in 74% of the patients at a steady state level of 6.9 +/- 3.7 mg/liter (mean +/- standard deviation). Nonresponders to procainamide had a mean steady state serum concentration of procainamide of 4.2 +/- 2.1 mg/liter (P less than 0.05). Systolic and diastolic blood pressures decreased moderately (10 and 8%, respectively), and heart rate decreased 11%. The infusion was interrupted in one patient because of hypotension. The duration of electrocardiographic conduction intervals was increased slightly in some patients. It is concluded that procainamide administered by this two infusion method is effective and well tolerated by most patients.

Arrhythmias, Cardiac↗
PubMed1978

Pharmacokinetic approach to intravenous procainamide therapy.

A pharmacokinetic approach was employed to design a dosing regimen for the i.v. use of procainamide (PA) which consisted of a loading infusion given over one hour followed by a maintenance infusion. Therapeutic serum concentrations of PA were achieved in less than 15 min, and toxic serum concentrations were avoided in 12 patients. A mean maximum serum concentration of PA of 5.78 mg/l was obtained with a loading infusion of 16.6 mg/min PA HCl. An average steady-state serum concentration of PA of 5.05 mg/l was obtained with a mean maintenance infusion of 222 mg/hour PA HCl. The total body clearance of PA in slow and fast acetylators averaged 31 and 43 l/h respectively. Use of PA in cardiac patients by i. v. infusion can be safe and effective therapy.

Acetylation↗
PubMedDate not supplied

Procainamide disposition in obesity.

The pharmacokinetics of intravenous procainamide (PA) were studied in seven obese and seven normal subjects. Serum concentrations and urinary excretion rates of PA and its active metabolite, NAPA, were measured by high performance liquid chromatography. Pharmacokinetic parameters were related to ideal body weight (IBW) and total body weight (TBW). The volume of distribution at steady state (Vssd) was similar for both groups when based per unit of IBW. Plasma clearance of PA, corrected for body surface area, was greater in obese subjects when adjusted for IBW, but similar on the basis of TBW. For its components, metabolic and renal clearance, the obese subjects showed similar metabolic clearances, but a significant increase was found in renal clearance per unit of body surface area based on both IBW (normal mean, 11.9 L/h/m2; obese, 19.0 L/h/m2) and TBW (normal mean, 11.7 L/h/m2; obese, 15.7 L/h/m2). This appears to be due to increased tubular secretion of PA in the obese group. In contrast, these subjects had lower renal clearances of NAPA. Variability in disposition of PA may, thus, be affected by patient physiology and method of parameter normalization.

Acecainide↗