Search PubMedSearch

Biomedical subjects

C M Swartz

Publications and source records attributed to C M Swartz.

At least 19 recordsLinked to original sources

Electroconvulsive therapy-induced cortisol release after dexamethasone in depression.

ECT-induced cortisol release was distinctly seen, and fell along a course of ECT in each of 12 inpatient male melancholics (p = 0.00024, binomial), with dexamethasone given to diminish the elevated baseline cortisol levels typically seen in depression. Cortisol release dropped on average by 55% (p = 0.015), from 16.6 +/- 6.8 micrograms/dl (p = 0.000002) with the first ECT to 8.0 +/- 7.7 micrograms/dl (p = 0.000003) after 6 or more ECTs. The fall along the course was larger with unilateral ECT than bilateral ECT (p = 0.042), although significant regardless of electrode placement, suggesting that unilateral ECT tends to lose therapeutic impact along a course in comparison to bilateral ECT.

Aged

Antidepressant effects of high-dose right unilateral electroconvulsive therapy.

In a random-assignment, double-blind, controlled comparison in 38 melancholic men, overall antidepressant potency of high-dose electroconvulsive therapy (378-mC charge) given with right unilateral electrode placement was not significantly different from that with bilateral placement, although there was a trend for faster improvement with bilateral ECT. The suprathreshold character of the stimulus, about 2.5 times the expected seizure threshold, may have contributed to the high efficacy of brief-pulse right unilateral electroconvulsive therapy found in this study.

Adult

Drug dose prediction with flexible test doses.

This article presents the first known practical method to apply one-compartment pharmacokinetic modeling to prediction of doses for drugs from one or more blood-drug concentrations, without requiring approximations or a computer. It should be useful for regulating doses of orally administered CNS drugs whose effects develop over a day or more, e.g., lithium, antidepressants, and anticonvulsants. Pharmacokinetic calculations for sequences of one, two, and three test doses are condensed into graphs that can be rapidly applied for clinical purposes. These graphs account for dose division, blood sampling time, and drug elimination rate; they show that the ratio of the steady-state day-mean drug level to the test-drug blood level is independent of the half-life if the test level is about a day after the last test dose. The calculations show the same value as experimental measurements for the ratio between steady-state serum lithium level and serum lithium level measured after a test dose. A rational strategy for drug-loading doses is discussed.

Central Nervous System Agents

Theophylline reversal of electroconvulsive therapy (ECT) seizure inhibition.

Oral sustained-release theophylline 200-400 mg, given 10 hours prior to electroconvulsive therapy (ECT) increased ECT seizure length in each of eight male patients who had shown unacceptably short seizures. The increase was on average 13.9 (+/- 6.0, SD) sec (p = .00016 by t test; p = .0000034 by exact probability). The absence of unduly prolonged seizures was attributed to previously demonstrated high seizure thresholds and to relatively low concentrations of theophylline. No adverse effects from theophylline were seen.

Aged

Determination of drug half-life while giving doses between blood samples.

Traditional methods of determining drug elimination half-life require that no doses be given between the blood samples, which delays drug administration. This article details a new method to determine drug half-life from blood samples drawn with intervening drug doses, that is, while blood levels are building rather than falling. This method was derived from one-compartment pharmacokinetic modeling to assist regulation of doses of central nervous system drugs whose blood concentrations have clinical meaning, for example, lithium and some antidepressants. It should improve the accuracy and practicality of pharmacokinetic methods to predict desirable steady-state drug doses at start-up and to monitor the total daily drug exposure during followup.

Half-Life

Albumin decrement in depression and cholesterol decrement in mania.

Within all psychiatric inpatients over a 4-year period, on admission depressives showed serum albumin 5.4% lower (P less than 0.001) than non-psychiatric controls. Similarly, manics showed cholesterol 10% lower (P less than 0.0005) and serum calcium/protein ratio 2.2% higher (P less than 0.05) than controls. These deviations suggest a tendency towards dietary aberrations in these patients of potential medical significance. These tests had shown the most distinct variation with diagnosis on split-half discriminant function analysis of routine chemistry and hematology tests of 107 patients with mania, 132 with depression, 67 with schizophrenia, 18 with schizoaffective illness, and 83 non-psychiatric controls admitted for elective surgery.

Adult

Electroconvulsive therapy emergence agitation and succinylcholine dose.

In this prospective study, five patients who had repeatedly shown troublesome restless emergence agitation after each of 20 sessions of electroconvulsive therapy (ECT) with a succinylcholine dose about .7 mg/kg showed no agitation after 15 ECT sessions in which the succinylcholine dose was increased to about 1.0 mg/kg. The probability that the pattern of response to higher succinylcholine dose resulted from random processes is less than .005. This provides evidence that patients predisposed to emergence agitation are sensitive to seizure-induced metabolic changes in skeletal muscle tissue and that the likelihood of emergence agitation rises with the ratio of skeletal muscle mass to succinylcholine dose. Because ECT-inducted serum lactate elevations are blocked by succinylcholine, emergence agitation might be essentially the same phenomenon as lactate-induced panic.

Adult

Multiple muscle enzyme release with psychiatric illness.

Associations (p less than .001) between serum concentrations of lactate dehydrogenase (LDH) and glutamic oxaloacetic transaminase (SGOT) were observed in physically well patients with mania (N = 100, r = .70), depression (N = 138, r = .51), chronic schizophrenia (N = 85, r = .68), and schizoaffective or atypical psychosis (N = 39, r = .52) discharged from 1978 through 1981. In contrast, there was a negligible association between these enzymes in 90 nonpsychiatric inpatient control subjects. Patients with mania (229.0 +/- 106.1 IU/l) showed significantly (t = 3.16, p less than .002, two-tailed) higher lactate dehydrogenase (LDH) levels than control subjects (191 +/- 41.7 IU/l) and a 14% incidence of abnormally high serum LDH levels vs. 1% among control subjects. Results were unchanged when patients taking neuroleptics were excluded. These results indicate that psychiatric illness, especially mania, induces release of LDH and SGOT, occasionally to unusually high levels. This is similar to previous reports of muscle creatine phosphokinase release in psychiatric patients. Presumably, these enzymes are released from skeletal muscle in association with agitation, with muscle tension, or with blood stasis and local tissue hypoxia consequent to hypoactivity.

Aspartate Aminotransferases

Serum prolactin levels during extended cocaine abstinence.

Following a report indicating almost a 100% risk for hyperprolactinemia in cocaine users after 1 month of abstinence, the authors determined the serum prolactin concentrations of 23 male inpatients who had abstained from cocaine for 2-43 weeks. None showed high prolactin levels; this places the incidence below 12.3% with 95% confidence. These results imply that persistent hyperprolactinemia requires a medical explanation other than cocaine abstinence itself.

Bromocriptine

Blood pressure reduction with ECT response.

A group of 48 male inpatients who responded to electroconvulsive therapy for major depression showed decreases in resting blood pressure along the course of treatment. Decreases occurred in both systolic (mean +/- SD = 8.0 +/- 17.3 mm Hg, p = .0025) and diastolic (7.4 +/- 13.2 mm Hg, p = .00030) pressures. Systolic pressure decreased by at least 20 mm Hg in 15 patients. These findings are consistent with reports that depressives show elevated plasma catecholamine levels, and that, with response to tricyclic antidepressants, their blood pressures decrease. Depression-associated blood pressure elevation might contribute to the excessive cardiac mortality of depressives; conversely, antidepressant treatment might control hypertension in some depressives.

Antidepressive Agents, Tricyclic

Correction of blood drug levels for changes over the day.

A graph-based method is presented to compensate for the influence of variations in drug dosage schedules and blood sampling times upon the blood concentrations of drugs whose elimination half-life is between 7 and 48 hours. This method permits the clinician to interpret blood drug levels drawn at nonstandard times, and to correct blood drug levels for how the daily dose was divided. This method is expected to improve the convenience of monitoring blood drug levels.

Blood Specimen Collection

Pharmacologic provocation and dexamethasone suppression test sensitivity.

In expectation of improving sensitivity, the standard 1-mg dexamethasone suppression test (DST) was given to 10 depressed inpatients and repeated with theophylline or caffeine and again following 3 days of lorazepam with abrupt discontinuation. Two patients showed nonsuppression on the standard DST; 2 suppressors changed to nonsuppression after lorazepam discontinuation, and 1 also changed after theophylline. This increase from 20 to 40% sensitivity remains significantly less than a desirable minimum 80% sensitivity (p less than 0.001), which suggests that a consistent DST sensitivity of 80% in melancholia is unlikely to be attained.

Caffeine