Search PubMed⌕ Search

Biomedical subjects

P A Singer

Publications and source records attributed to P A Singer.

173 records · Page 10Linked to original sources
PubMed1973

Assessment of thyrotropin-releasing hormone and thyrotropin reserve in man.

Endogenous thyrotropin-releasing hormone (TRH) reserve and pituitary thyrotropin (TSH) reserve were assessed in four normal subjects, three patients post-cryohypophysectomy, one patient with a hypothalamic lesion secondary to trauma, and four patients with Sheehan's syndrome. TSH reserve was determined by the immunoassayable TSH response to 500 mug TRH given i.v. (TRH stimulation test). TRH reserve was assessed by the rebound response in thyroidal iodine release (TIR) following withdrawal of pharmacologic doses of prednisolone (glucocorticoid withdrawal test). When compared with normals, the post-cryohypophysectomy patients demonstrated parallel impairment of TRH stimulation and glucocorticoid withdrawal testing. The patient with the hypothalamic lesion and the four patients with Sheehan's syndrome all had normal TRH stimulation tests, indicating adequate TSH reserve capacity, yet had abnormal glucocorticoid withdrawal tests, indicative of impairment in endogenous TRH reserve or neurohumoral transport. Three of the patients (hypothalamic injury and two Sheehan's) with impaired TRH reserve were euthyroid. THE FOLLOWING CONCLUSIONS WERE REACHED: (a) A combination of the TRH stimulation test and glucocorticoid withdrawal test may allow for differentiation between pituitary and suprahypophyseal disorders. (b) Certain cases of Sheehan's syndrome appear to have impaired endogenous TRH reserve or transport. (c) Euthyroidism can be maintained in spite of diminished TRH reserve.

Adolescent↗
PubMedDate not supplied

Accuracy of clinical impressions and Mini-Mental State Exam scores for assessing capacity to consent to major medical treatment. Comparison with criterion-standard psychiatric assessments.

The authors evaluated the accuracy of clinical impressions and Mini-Mental State Exam scores for assessing patient capacity to consent to major medical treatment, relative to expert psychiatric assessment. Consecutive medical inpatients (N = 63) facing a decision about major medical treatment received a clinical impression of capacity from their treating physician and the Standardized Mini-Mental State Exam (SMMSE); 48 received independent psychiatric assessment of capacity. Analyses revealed that both clinical impressions and SMMSE scores were generally inaccurate in determining capacity, although all 23 participants with a clinical impression of "definitely capable" were found capable by the psychiatrist. Given the importance of assessing capacity to consent to major medical treatment, better approaches to the clinical assessment of capacity are required. Several strategies are discussed.

Adult↗
PubMedDate not supplied

Referral for dialysis in Ontario.

BACKGROUND: Because the incidence rates of treated end-stage renal disease are much lower in Canada than in the United States, we hypothesized that decisions, made by family physicians and community internists, not to refer certain patients to nephrologists might explain this difference. OBJECTIVE: To elicit patterns of practice and attitudes from nonnephrologist physicians who care for, and possibly refer, patients with renal disease. METHODS: A mailed survey was sent to a random sample of 1924 members of the Ontario Medical Association, Sections on General and Family Practice and Internal Medicine. Of 1778 eligible respondents, responses were received from 728 physicians (40.9%). RESULTS: Patients with microscopic hematuria (79.2%), proteinuria (69.5%), and serum creatinine levels in the 120 to 150 mumol/L (1.4 to 1.7 mg/dL) range (84.3%) were generally not referred by family physicians. A hypothetical question about patient age and comorbid features revealed that physicians were less likely to refer patients as their age and comorbidity increased. In response to the question, "In the past 3 years, did you care for a patient who, after due consideration, died of renal failure without referral for dialysis," 14.2% of family physicians and 44.6% of internists said yes. Overall, 67.4% of respondents strongly or somewhat agree that rationing of dialysis is occurring now. Opinions about possible criteria for rationing of dialysis were that the majority strongly or somewhat agreed to basing a decision on the wishes of a competent patient (94.1%), short life expectancy (87.9), poor quality of life (87.0%), and age (63.6%). CONCLUSIONS: These results suggest that nonreferral for dialysis occurs in Ontario and that the act of referral, or nonreferral as the case may be, is influenced by both age and coexisting disease. The patterns of nonreferral reported raise a concern that patients who might benefit are not being referred to dialysis centers.

Age Factors↗