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P Crome

Publications and source records attributed to P Crome.

At least 19 recordsLinked to original sources
PubMed2001

Drug absorption may be delayed after stroke: results of the paracetamol absorption test.

BACKGROUND: Autonomic changes are frequent after stroke but it is not known whether gastric emptying is altered. We have investigated this using the paracetamol absorption test. METHODS: 12 acute stroke patients and 13 healthy controls of similar age received 1 g oral paracetamol tablets. We studied all patients within 24 h of the stroke and 5 days later. Standard pharmacokinetic measurements were derived from the plasma paracetamol-time curve. RESULTS: In acute stroke patients, mean plasma T(max) was delayed compared with that in controls (96.3 vs 46.2 min, P=0.015). The C(max) of paracetamol was also lower (16.1 vs 23.9 mg l(-1), P=0.028). The area under the curve of paracetamol did not differ significantly in acute stroke patients and controls. CONCLUSIONS: Gastric emptying appears to be delayed in acute stroke patients, and this may result in delayed pharmacological action of orally administered drugs.

Acetaminophen↗
PubMed2001

Effect of hemiparetic stroke on pulse oximetry readings on the affected side.

BACKGROUND AND PURPOSE: Hypoxia is common after stroke, and monitoring by pulse oximetry is suggested in the acute phase. Physical changes on the affected side or intravenous infusions may affect oximeter readings. This study was designed to test whether pulse oximetry recordings are the same on the affected and nonaffected sides in stroke patients. METHODS: Oxygen saturation (SpO(2)) and heart rate (HR) were assessed simultaneously in the left and right hands in patients with hemiparetic stroke over a 3-hour period with 2 Minolta Pulsox-3i oximeters attached to the index fingers. RESULTS: Fifteen patients (53% men; 67% left hemiparesis; mean age, 73 years [SD, 7.5 years]) were recruited. HR and SpO(2) (12 measurements per minute) were monitored. The maximum difference between simultaneous left and right arm readings was 2% SpO(2). HR fluctuated more, but no affected/nonaffected side pattern was seen. Means for each patient of HR and SpO(2) for the affected and nonaffected sides were compared by t tests. Mean SpO(2) was 96% (SD, 1%) on both sides. Mean HR was 81 bpm (SD, 11 bpm) on the affected side and 80 bpm (SD, 10 bpm) on the nonaffected side. There was no significant difference between the 2 sides for either parameter (n=15; P=0.86 for SpO(2) and P=0.91 for HR). CONCLUSIONS: Oximeters can be attached to either the affected or nonaffected side in hemiparetic stroke.

Aged↗
PubMed2000

Domiciliary visits to the old and the mentally ill: how valuable?

In the early days of the British National Health Service, domiciliary visits were a continuation of the tradition whereby general practitioners (GPs) met consultants in the patient's home. The nature of domiciliary visits, which still attract a special fee, has since changed. We analysed the effectiveness of all domiciliary visits undertaken in a NHS trust providing primary care, mental health and elderly care services to a population of 470,000. Data were obtained from domiciliary visit claim forms and from questionnaires completed by the consultant, the referring GP and consultant peer reviewers. The largest number of visits (total 234) was in geriatric medicine 48.9%, followed by old-age psychiatry 44.9%. Geriatric medicine was more likely than psychiatry to admit patients to hospital (19%) after a visit. All domiciliary visits in old-age psychiatry were done during the day (9 am to 5 pm). Only 2% of GPs stated that they attended any of the domiciliary visits; almost all thought that the outcome of domiciliary visits was of value. Old-age-psychiatry peer reviewers believed that all visits in that specialty were appropriate; in geriatric medicine this figure was 77% and in other psychiatric specialties 65%. The findings indicate that domiciliary visits were not being used routinely as a pathway to hospital admission, though they were often used to expedite admission or gain a quick consultant opinion; the visits were valued by GPs. The practice of domiciliary visits differs greatly from the definition in NHS terms and conditions of service. One or other should be altered.

Aged↗
PubMed1999

Orthostatic haemodynamic responses in acute stroke.

Little is known about orthostatic blood pressure regulation in acute stroke. We determined postural haemodynamic responses in 40 patients with acute stroke (mild or moderate severity) and 40 non-stroke control in-patients, at two days ('Day 1') and one week ('Week 1') post-admission. Following a 10-minute supine rest and baseline readings, subjects sat up and blood pressure and heart rate were taken for 5 minutes. The procedure was repeated with subjects moving from supine to the standing posture. Haemodynamic changes from supine data were analysed. On standing up, the control group had a transient significant fall in mean arterial blood pressure on Day 1 but not Week 1. No significant changes were seen on either day when sitting up. In contrast to controls, the stroke group showed increases in mean arterial blood pressure on moving from supine to the sitting and standing positions on both days. Persistent postural hypotension defined as > or = 20 mmHg systolic fall occurred in < 10% of either of the study groups on both days. Sitting and standing heart rates in both groups were significantly faster than supine heart rate on both days. The orthostatic blood pressure elevation is consistent with sympathetic nervous system overactivity which has been reported in acute stroke. Upright positioning as part of early rehabilitation and mobilisation following mild-to-moderate stroke would, therefore, not predispose to detrimental postural reductions in blood pressure.

Aged↗
PubMed1997

Health status and disability among elderly people in three UK districts.

AIM: To obtain population data on health status and disability of elderly people which may help in planning and maintaining services and be used as comparators for research. METHOD: Random samples of people aged 70 and over were interviewed in their own homes in West Glamorgan, Dudley and North Staffordshire. The interviews included standardized assessments of health status (SF-36), disability (Barthel index) and cognitive function (Abbreviated Mental Test). RESULTS: 1608 interviews were completed. Response rates varied between 66 and 84%. Age and sex adjusted scores for five of the eight parameters of the SF-36 and the Barthel score differed significantly between districts. CONCLUSIONS: Local studies are required to provide appropriate normative data for each area. In the absence of such studies, the data in this paper are the best currently available.

Activities of Daily Living↗
PubMed1997

Clinical pharmacokinetic considerations in the elderly. An update.

There are a number of areas in which advances have been made over the last few years in the area of pharmacokinetics in the elderly. There is increasing understanding of the diversity of cytochrome P450s (CYP) and the variability of the age-related decline in CYP activity. This has helped to explain some of the interindividual variability in drug metabolism with age. The importance of ethnic differences has emerged, but specific work is needed in this area in the elderly. Differences in the handling of chiral compounds has been reported but as yet no clinically important findings that may lead to a change in clinical practice have emerged. The emerging importance of extrahepatic drug metabolism, especially in the intestine, has added a new complexity to our understanding of pharmacokinetics. The issue of frailty is also discussed in this article. Whether it will be of value at the bedside has yet to emerge. Nonetheless, as a concept, recent data has supported its potential use to define those more at risk of clinically meaningful pharmacokinetic alterations. Other advances have included the appreciation that selectivity in induction and inhibition in the elderly are due to the existence of multiple CYP forms. Similarly, the role of these various enzymes in disease is also improving our clinical understanding, as exemplified in Parkinson's disease.

Aged↗
PubMed1996

Inhibition of dihydropyrimidine dehydrogenase by 5-propynyluracil, a metabolite of the anti-varicella zoster virus agent netivudine.

OBJECTIVE: To study the effects of the anti-herpetic drug netivudine on dihydropyrimidine dehydrogenase activity in elderly volunteers and to relate them to concentrations of netivudine and its metabolite 5-propynyluracil. METHODS: Three groups of eight elderly volunteers received 400 or 800 mg netivudine or placebo once daily for 8 days. Plasma netivudine, 5-propynyluracil, and uracil, an indirect measure of dihydropyrimidine dehydrogenase activity, were assayed before the first dose and on days 2, 3, 5, 7 and 8. Full plasma profiles of netivudine and 5-propynyluracil were determined after the last dose. RESULTS: Plasma uracil was unquantifiable in all subjects before the first dose and at all time points in the placebo group. In recipients of netivudine it reached a plateau between days 3 and 5, with mean values of 23.2 and 23.5 mumol/L on day 8 in the subjects who received 400 and 800 mg. Plasma netivudine concentrations were approximately dose proportional, but 5-propynyluracil concentrations were similar in both groups. The half-maximal rise in plasma uracil occurred after a cumulative 5-propynyluracil exposure of 120 mumol/L.hr; such exposures will be achieved even after doses as low as 50 to 100 mg daily. CONCLUSIONS: Netivudine dosing produces complete inhibition of plasma dihydropyrimidine dehydrogenase. Coadministration with the antimetabolite 5-fluorouracil will require a substantial reduction in 5-fluorouracil dose to avoid toxicity but may also improve the therapeutic index of 5-fluorouracil.

Aged↗
PubMed1996

Multiple dose netivudine, a potent anti-varicella zoster virus agent, in healthy elderly volunteers and patients with shingles.

Netivudine is a nucleoside analogue with potent anti-varicella zoster virus activity. We now report two open studies of the pharmacokinetics and tolerability of netivudine in doses of 50, 100 and 200 mg twice daily. In one study, healthy volunteers received an initial, single dose followed, a week later, by repeat dosing for 9 1/2 days; in the other, patients with shingles were treated for 8 days and data were also recorded for rash resolution and pain duration and intensity. Netivudine was well tolerated in both studies. Plasma concentrations were similar in patients and healthy volunteers and increased in proportion to dose. Steady state concentrations were 15-25% lower than expected from single dose data, probably because of slightly decreased netivudine absorption after food. Elimination half-life was l4-20 h. Plasma concentrations of 5-propynyluracil (5-PU), the main metabolite of netivudine, did not increase in proportion to the netivudine dose and tended to be higher in patients than volunteers. 5-PU concentrations remained elevated for up to 72 h after the last netivudine dose, suggesting continued but slow release from unabsorbed netivudine in the gut lumen. New lesion formation ceased and vesicles crusted most quickly in the 200 mg group; zoster-associated pain intensity, was reduced in a dose-related manner.

Aged↗
PubMed1995

Pharmacokinetics and tolerability of single oral doses of 882C87, a potent, new anti-varicella-zoster virus agent, in healthy volunteers.

882C87 is a nucleoside analog with potent, specific activity against varicella-zoster virus. It is approximately seven times as potent as acyclovir with an in vitro 50% inhibitory concentration of 1 to 2 microM. The tolerability and pharmacokinetics of single doses of 882C87 have been investigated in a series of studies with healthy young and elderly adult volunteers. The young received 50 to 1,600 mg, and the elderly received 50 and 100 mg. Concentrations of 882C87 and its main metabolite, the pyrimidine base 5-(1-propynyl)uracil (5PU), in plasma and urine were assayed by an automated sequential trace enrichment of dialysate-high-performance liquid chromatography procedure, and noncompartmental pharmacokinetic parameters were derived from the data. Concentrations of 882C87 in plasma increased proportionally for doses of up to 400 mg, but after higher doses the increase was less than dose proportional. In young adults, after 200, 400, and 1,600 mg, the maximum concentrations of the drug in plasma were 9.0, 16.3, and 34.7 microM, respectively, and the areas under the concentration-time curve (AUC) from 0 h to infinity were 166.6, 333.7, and 822.9 microM.h, respectively. Elimination half-life was 11.3 to 13.0 h after 50 to 400 mg, increasing to 15.3 h after 1,600 mg, associated with a small decrease in renal clearance. In healthy elderly volunteers concentrations of 882C87 in plasma after 50 and 100 mg were similar to those in young adults after twice the dose; apparent clearance and renal clearance were significantly reduced, and half-life was significantly longer at 15 h. Administration of 882C87 with food produced a small, nonsignificant reduction in mean AUC from 0 h to infinity, but in subjects with a low fasting AUC there was an increase after food and in subjects with a high fasting AUC there was a decrease. Concentrations of 5PU in plasma were one-third to one-half those of 882C87 and, in most subjects, were not dose proportional. There was a lag of at least 5 h after dosing with 882C87 before 5PU was detectable in plasma.

Administration, Oral↗
PubMed1994

Evaluation of a clinical score for prognostic stratification of elderly stroke patients.

Orpington Prognostic Score (OPS) is a clinically derived score which incorporates measures of motor deficit, proprioception, balance and cognition. OPS and urinary continence were measured prospectively in 217 stroke survivors over 75 years of age at 1, 2 and 4 weeks after stroke and were correlated with dependence at discharge. Three levels of dependence were defined based on personal self-care abilities. OPS ranged from 2.0 to 3.2 (median 2.8) at 2 weeks after stroke in patients independent at discharge (n = 54). Their initial median Barthel index of 4 improved by a median of 12. Urinary continence was achieved in 95% of these patients by 2 weeks. All patients were discharged home, 39 (72%) within 4 weeks. Patients with limited dependence at discharge (n = 129) had OPS of 3.2-4.8 (median 4.0) at 2 weeks. Two-thirds were continent at 2 weeks. Their initial median Barthel index was 2 and changed by a median of 12. Seventy-one (55%) of these patients went home. OPS ranged from 5.2 to 6.8 (median 6.0) at 2 weeks in patients dependent at discharge (n = 34). About 20% of these patients were continent. Their initial median Barthel index of 2 improved by a median of 6 at discharge. Only five (15%) patients in this group went home. OPS was comparable with urinary incontinence for sensitivity (96% vs. 90%), specificity (36% vs. 39%) and accuracy (75% vs. 66%) in identifying stroke patients achieving independent living. OPS had a greater predictive value than urinary incontinence in identifying patients requiring institutional care (82% vs. 57%). OPS is a simple objective predictor of outcome in elderly stroke patients, suitable for everyday clinical use. It also can facilitate stroke research by identifying a 'middle group' of patients who would be most sensitive to changes in therapy or organization of stroke services.

Activities of Daily Living↗