Robin Briant

Interaction between Clonidine and Desipramine in Man

Interaction between the tricyclic antidepressant desipramine and the antihypertensive agent clonidine has been investigated in five hypertensive patients in a double-blind placebo controlled study. Introduction of the tricyclic antidepressant led to loss of blood pressure control in four of the patients. The average blood pressure rise in the desipramine period compared with the placebo period was 22/15 mm Hg in the lying position and 12/11 mm Hg standing. Thus addition of a tricyclic antidepressant may lead to loss of blood pressure control in a hypertensive patient treated with clonidine.

Theophylline target concentration in severe airways obstruction : 10 or 20 mg/L ? A randomised concentration-controlled trial

SummaryThe optimal serum concentration of theophylline for the management of acute airways obstruction was evaluated by comparing the response to target concentrations at the extremes of the usual therapeutic range. 174 patients requiring intravenous theophylline were randomly assigned to a target concentration of 10 or 20 mg/L. Control of theophylline dosage using measured theophylline concentrations and evaluation of efficacy and toxicity was performed under double-blind conditions. 87 patients (50%) required hospital admission. Of these, 54 patients (62%) were followed throughout their hospital admission and reviewed at an outpatient clinic approximately 1 week after discharge. The duration of hospital stay, and rate and extent of improvement in peak expiratory flow rate were not different between the groups. There was significantly more toxicity in the 20 mg/L group. The initial target concentration for theophylline in the management of acute airway obstruction should be 10 mg/L under circumstances where concentration is used to control theophylline dosages.

Preventable in-hospital medical injury under the “no fault” system in New Zealand

Objectives: To describe the pattern of preventable in-hospital medical injury under the “no fault” system and to assess the level of serious preventable patient harm. Design: Cross sectional survey using a two stage retrospective assessment of medical records conducted by structured implicit review. Setting: General hospitals with over 100 beds providing acute care in New Zealand. Participants: A sample of 6579 patients admitted in 1998 to 13 hospitals selected by stratified systematic list sample. Main outcome measures: Occurrence, preventability, and impact of adverse events. Results: Over 5% of admissions were associated with a preventable in-hospital event, of which nearly half had an element of systems failure. The elderly, ethnic minority groups, and particular clinical areas were at higher risk. The chances of a patient experiencing a serious preventable adverse event subsequent to hospital admission were just under 1%, a figure close to published results from comparable studies under tort. On average, these events required an additional 4 weeks in hospital. System related issues of protocol use and development, communication, and organisation, as well as requirements for consultation and education, were pre-eminent. Conclusions: The risk of serious preventable in-hospital medical injury for patients in New Zealand, a well established “no fault” jurisdiction, is within the range reported in comparable investigations under tort.

Quality of hospital care for Māori patients in New Zealand: retrospective cross-sectional assessment

BACKGROUND New Zealand has a substantial indigenous minority--the Māori--that has considerably worse health status than the majority population. We aimed to assess possible disparities in quality of hospital care for Māori with data on preventable adverse events as an indicator of suboptimum treatment. METHODS We undertook a nationally representative cross-sectional survey of admissions to general public hospitals with more than 100 beds providing acute care. A sample of 6579 patients admitted in 1998 to 13 hospitals was selected by stratified systematic list sample. We did a two-stage retrospective assessment of records by structured implicit review. Outcome measures were occurrence, effect, and preventability of adverse events. FINDINGS Māori accounted for just greater than 15% of admissions and were on average younger, were more likely to be from from deprived areas, had a different case mix, and were in hospital for a shorter stay compared with patients of non-Māori/non-Pacific origin. Overall, after age standardisation, 14% of admissions for Māori were associated with an adverse event, compared with 11% for non-Māori/non-Pacific patients (p=0.01 for difference between groups). For preventable, in-hospital events, this disparity persisted after controlling for age, other sociodemographic factors, and case mix (adjusted odds ratio 1.47; p=0.05). Analysis of potential causal factors showed no markedly or consistently different pattern between the groups. INTERPRETATION Despite a predominantly publicly funded hospital system, our findings suggest that hospital care received by Māori is marginally poorer than that received by New Zealand citizens of non-Māori/non-Pacific origin. Although no cause specific to Māori was evident, various policy and system issues can be addressed.

The Rate of Acetaminophen Metabolism in the Elderly and the Young

ABSTRACT: Twenty‐eight elderly volunteers of the 65+ age group and 28 control subjects of the 20–40 age group each received a single oral dose (1 gm) of acetaminophen in powder form. The plasma level of acetaminophen was measured over 6 hours. Plasma half‐life, clearance and relative volume of distribution of the drug were calculated. Within each age group there was a wide (threefold) range of plasma half‐life and clearance rate, with a great deal of overlap between the two groups. However, for the elderly, the group mean half‐life of acetaminophen was 2.17 hours, significantly longer than for the young (1.75 hours). The clearance rate in the elderly was significantly slower than in the young (.254 and .340 L/kg/hour respectively). There was no age‐related difference in volume of distribution of the drug by any measure, and no significant influence of sex.

Cost of medical injury in New Zealand: a retrospective cohort study.

Objective To estimate the cost of treating medical injury associated with hospital admissions in New Zealand and the patient characteristics of costly adverse events. Methods As part of the New Zealand Quality in Healthcare Study (NZQHS), a retrospective examination of medical records in 13 public hospitals identified the occurrence of clinical procedures and hospital bed days attributable to adverse events. The prices charged to foreign patients were used to estimate the cost of the health care resources used. Results 850 adverse events were identified in the NZQHS which cost an average of

Metabolism of Δ1‐tetrahydrocannabinol by the isolated perfused dog lung. Comparison with in vitro liver metabolism

NZ 10 264 per patient. For New Zealand, adverse events are estimated to cost the medical system

The Metabolism of Sympathomimetic Bronchodilator Drugs by the Isolated Perfused Dog Lung

NZ 870 million, of which

Compensation for Medical Injury in New Zealand: Does “No-Fault” Increase the Level of Claims Making and Reduce Social and Clinical Selectivity?

NZ 590 million went toward treating preventable adverse events. The results suggest that up to 30% of public hospital expenditure goes toward treating an adverse event. The results also suggest that older patients, neonates and those with moderately serious co-morbidity tended to have more costly adverse events. Conclusions Adverse events lead to a significant use of health care resources in New Zealand. These findings suggest that substantial resources could be saved by eliminating preventable adverse events.

The influence of the route of administration on urinary metabolites of isoetharine.

The metabolism of (—)‐Δ1‐tetrahydrocannabinol (Δ1‐THC) has been studied in the isolated perfused dog lung. After intravascular administration of [3H]‐Δ1‐THC there was an overall biotransformation of 12%. Two major metabolites were isolated and identified as 3“‐hydroxy‐Δ1‐THC and 4”‐hydroxy‐Δ1‐THC. 7‐Hydroxy‐Δ1‐THC was also present together with small amounts of 6α‐hydroxy‐Δ1‐THC and 6β‐hydroxy‐Δ1‐THC. An in vitro experiment using a dog liver microsomal preparation was also carried out and showed that the major metabolites were 6β‐hydroxy‐Δ1‐THC and 6α‐hydroxy‐Δ1‐THC. 7‐Hydroxy‐Δ1‐THC and 1,2‐epoxy‐hexahydrocannabinol were also isolated together with small amounts of 3“‐hydroxy‐Δ1‐THC and 4”‐hydroxy‐Δ1‐THC. The side‐chain hydroxylated compounds are hitherto undescribed metabolites of Δ1‐THC.