Showing papers by "Glenfield Hospital published in 1994"

Domains, constructs and the development of the breathing problems questionnaire

Abstract: Health-related quality of life (QoL) questionnaires are commonly developed as content valid instruments with conventionally defined domain subscales. We contrasted content valid domain subscales with construct valid construct subscales and developed a 13-domain QoL questionnaire, the Breathing Problems Questionnaire (BPQ), for patients with chronic bronchitis. In a series of studies, we examined the constructs relevant to COPD patients' experience of health. First, we provided psychometric evidence that items in the BPQ form two distinct groups: functional problems and negative evaluations. Second, we showed that problems were significantly more correlated with morbidity whereas negative evaluations were significantly more correlated with neuroticism. Third, we showed that negative evaluations correlated with neuroticism whereas positive evaluations (measured by the Satisfaction with Illness Scale) correlated with extraversion. Patients are more likely to make positive evaluations of their illness when they recognize that they are seriously ill. Most of the BPQ domains are subcategories of the construct of problems: both domains and construct classifications provide useful information.

Evidence for the Involvement of Oxygen-Derived free Radicals in Ischaemia-Reperfusion Injury

Abstract: Six patients undergoing vascular reconstructive surgery were examined for evidence of oxygen-derived free radical (ORF) damage to the protein, immunoglobulin G (IgG). OFR damage was determined as an increase in the fluorescence (ex 360 nm em 454 nm) to ultraviolet absorption (280 nm) ratio of IgG, representing N-Formyl kynurenine and other as yet unidentified fluorophores. The IgG ratio was found to increase slightly during ischaemia and to undergo marked elevation upon reperfusion (275 +/- 405% baseline value at 40 min post-clamp; mean +/- sd). A high ratio was maintained post-reperfusion, even after 60 min reperfusion. Determination of thromboxane B2, (TXB2), leukotriene B4, (LTB4) and 6-keto prostaglandin F1 alpha, (PGF1a), revealed a decrease in their concentrations during ischaemia and a transient, marked increase on reperfusion. Only TXB2 concentrations were found to correlate with the IgG ratio (negative correlation, p < 0.05). No correlation was observed between von Willebrand antigen factor, a marker of endothelial cell damage and fluorescent IgG ratio. However, levels of the factor increased slightly during ischaemia and more sharply upon reperfusion. These preliminary results therefore suggest that a more likely source of the OFRs responsible for IgG damage is endothelial cell xanthine oxidase, rather than cyclo-oxygenase or lipoxygenase.

Value of physical signs in the diagnosis of ventricular tachycardia.

Abstract: BACKGROUNDAlthough the use of physical signs for the diagnosis of ventricular tachycardia (VT) was described in the early 1900s, their value in this role has never been systematically assessed.METHODS AND RESULTSUsing a blinded, randomized protocol, we examined the ability of 26 clinicians to detect ventriculoatrial (VA) dissociation during cardiac pacing in 21 patients with both atrial and ventricular pacing wires in situ after successful ablation of accessory pathways. In protocol 1 (10 patients), pacing was randomized to either ventricular pacing alone (simulating VT) or to atrioventricular sequential pacing (simulating supraventricular tachycardia or VT with intact VA conduction) at rates of 150 or 180 beats per minute. Each patients was examined by four clinicians blinded to the pacing mode. Clinicians were asked to make a diagnosis of "VA association" or "VA dissociation" after examining the patient for variability of the arterial pulse, jugular venous pulse (JVP), and first heart sound. In protocol...

Effects of intravenous adenosine in patients with preexcited functional tachycardias: Therapeutic efficacy and incidence of proarrhythmic events

Abstract: It is concluded that adenosine is effective in terminating preexcited junctional tachycardias, but may be complicated by serious proarrhythmic effects in these patients. These proarrhythmic effects of adenosine (1) preclude its use as the agent of first choice in the acute treatment of arrhythmias in which this diagnosis is suspected, and (2) highlight the need for continuous electrocardiographic monitoring and availability of direct-current cardioversion when adenosine is used as a diagnostic agent in wide-complex tachycardias of unknown origin.

Possibilities for antihypertensive drug therapy withdrawal in the elderly.

Abstract: The aims of this study were to determine: (1) the proportion of elderly hypertensive subjects currently attending a hospital hypertension clinic suitable for a trial of antihypertensive drug withdrawal, (2) the proportion of suitable patients who can be successfully withdrawn from drug therapy while receiving nonpharmacological advice, and (3) the factors associated with successful withdrawal. One hundred and five consecutive hypertensive subjects, 53% female, mean age 76 years (range 65-84 years) on pharmacological antihypertensive therapy for > 1 year were studied, of whom 78 (74%) had a clinic SBP or = 160 mmHg and/or DBP > or = 90 mmHg on two consecutive visits. After 12 months, 20 (25%) of those withdrawn remained normotensive, the majority restarting therapy did so in the first three months.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinic and 24h blood pressure in elderly treated hypertensives with postural hypotension.

Abstract: The objectives of this study were to determine the prevalence of, and factors associated with, postural hypotension (PH) in elderly treated hypertensive subjects, to examine the 24h BP profile in those subjects with and without PH and to determine the effects of antihypertensive treatment withdrawal on the prevalence and symptoms of PH. Eighty-six subjects (mean age +/- standard deviation 76 +/- 6 years) on antihypertensive drug therapy for > 6 months had three clinic BP measurements taken in supine and standing positions followed by 24h ambulatory BP monitoring. Forty-seven subjects underwent repeat BP measurement five weeks after withdrawal of antihypertensive medication and institution of standard nonpharmacological methods. Twenty-six (30%) of the 86 subjects exhibited PH (defined as SBP fall on standing > or = 20 mmHg) within three minutes of standing. Supine clinic and 24h SBP and DBP, age and presence of previous cardiovascular events were similar in the groups with and without PH. There was a significant correlation between the orthostatic BP fall for all subjects and day-night SBP difference (r = -0.30, P = 0.01) and urinary sodium:creatinine ratio (r = -0.33, P = 0.04). Multiple regression analysis revealed only the day-night SBP difference was a significant predictor of orthostatic BP change. In the PH group, 19 subjects had treatment withdrawn resulting in a reduction of 58% (P > 0.001) in those continuing to demonstrate PH. If indicated a trial of antihypertensive drug treatment withdrawal could reduce the risk of PH; the additional benefit of instituting nonpharmacological therapy in reducing BP and orthostatic hypotension warrants further assessment.

Absence of a prothrombotic state in restenotic patients

Abstract: AIMS To determine whether, in patients undergoing percutaneous transluminal coronary angioplasty (PTCA), there are prothrombotic markers indicating those with a predisposition to restenosis. METHODS Venous blood samples were obtained from patients undergoing PTCA for chronic stable angina. Patients with restenotic lesions, conduit stenoses or occlusive lesions were not included in the study. Samples were assayed for coagulation factors (fibrinopeptide A, antithrombin III, protein C), fibrinolytic factors [tissue-type plasminogen activator (t-PA), alpha 2 antiplasmin, plasminogen activator inhibitor (PAI-1)] and markers of platelet activation (platelet factor 4, beta thromboglobulin). RESULTS Of 46 patients who underwent successful PTCA, restenosis, defined as loss in absolute gain of more than 50%, occurred in 16 (35%). The minimal luminal diameter (mean +/- SD) at follow-up in those who had suffered restenosis was 1.07 +/- 0.7 mm compared with 1.73 +/- 0.5 mm in the non-restenotic patients. However, no significant differences in the levels of markers of platelet activation, coagulation factors, or fibrinolytic factors were observed between the two groups. The only significant difference between the groups was a higher platelet count in the restenotic patients [median (interquartile range): 263 (247-278) versus 224 (175-263), P < 0.05]. CONCLUSION Our results suggest that patients who suffer restenosis following PTCA appear to have no clearly detectable pre-existing imbalance in their prothrombotic/antithrombotic status. Although the platelet count was higher in restenotic patients, the levels of markers of platelet activation were no different in the two groups. Thus, it is at present unlikely that simple blood assays before PTCA assessing an individual's 'thrombotic state' can help to predict which of the 30-40% of patients undergoing PTCA will suffer restenosis.

Hospital management in the 1990s: fundholding consultants?

Abstract: Explores a model of clinical management which attempts to cope with the management-professional conflict and seeks to enable the hospital to run effectively and efficiently. Two key goals are identified for the hospital which are: to support consultant staff and provide physical and emotional support for patients. Notes that clinical services do not lend themselves to bureaucratic management and that there needs to be two distinct and parallel organizations within the hospital. Outlines the new structure for clinical service management.

Appropriate indications for radiofrequency catheter ablation.

Abstract: Most cardiologists take a very conservative approach to treatment of benign ventricular extrasystoles, usually advising no treatment or perhaps ,B blockade if a patient has significant symptoms. On page 492 Gumbrielle and coworkers describe the apparently successful use of radiofrequency catheter ablation in a patient with this common clinical condition. Should these patients (or an identifiable subgroup) be referred for ablation? In considering the indications for radiofrequency catheter ablation, like those for any treatment, the efficacy and safety of the procedure need to be taken into account, in addition to the symptoms and prognosis of the condition to be treated.

Effects of N-methyl hexanoylhydroxamic acid (NMHH) and myoglobin on endothelial damage by hydrogen peroxide

Abstract: Objective: The aim was to investigate the interaction of the novel antioxidant N-methyl hexanoylhydroxamic acid (NMHH) with myoglobin in protecting endothelial cells against H2O2 mediated damage. Methods: Cultured bovine aortic endothelial cells were exposed to 50–100 μM H2O2 for 10–60 min with and without NMHH and/or myoglobin, and immediate or delayed damage was assessed by lactate dehydrogenase release, 3H adenine uptake, a tetrazolium reduction assay, and microscopy. Results: Brief exposure to low concentrations of H2O2 caused cell damage, for which the tetrazolium reduction assay was the most sensitive assay, and inhibited subsequent cell division. NMHH in concentrations from 50 to 200 μM protected against damage provided it was present at the time of adding H2O2, and the effect was markedly potentiated by 10 μM oxymyoglobin, which had little protective effect alone. Conclusions: NMHH is an effective antioxidant which is markedly potentiated by low concentrations of oxymyoglobin. Oxymyoglobin may potentiate NMHH by scavenging H2O2 through the rapid formation of ferrylmyoglobin, which is then reduced by NMHH. This synergism may be particularly relevant to the protection of myoglobin-rich cells such as myocytes. Cardiovascular Research 1994; 28 :1641-1646

Clinical significance of heparin in the residual pump oxygenator blood, reinfused postoperatively after cardiopulmonary bypass:

Abstract: Postcardiopulmonary bypass (CPB) heparin levels and thrombin time were measured in 20 patients following routine open cardiac operations.There was a statistically significant increase in heparin co...

Targeted antiplatelet therapy.

Abstract: Antiplatelet therapy has been demonstrated to be beneficial in a variety of vascular disorders. This was confirmed in a recently reported meta-analysis of antiplatelet therapy use and benefit in acute myocardial infarction, unstable angina, secondary prevention after myocardial infarction, arterial thrombosis after angioplasty, occlusion of saphenous vein coronary grafts, stroke prevention after previous transient ischemic episodes and strokes, and prevention of deep venous thrombosis and pulmonary embolism in high risk individuals. 1-3 ISIS-2, a large randomised study of patients presenting with suspected acute myocardial infarction, showed that aspirin alone at a dose of 162.5 mg reduced 35 day mortality by 23% and had a synergistic effect when administered with streptokinase (mortality reduction of 42'X,).4 The most widely used antiplatelet agent both in clinical practice and in clinical trials is aspirin, with doses ranging from 75 mg to 1500 mg daily. Other antiplatek t agents in general clinical use include dipyridamole and ticlopidine. There is little data to suggest that these agents are more effective than a ~ p i r i n . ~ . ~ Aspirin, however, does have limitations as an antiplatelet agent, and more potent agents may produce greater clinical benefit in conditions such as unstable angina, acute myocardial infarction (both in improving re-establishment of vessel patency and reducing vessel reocclusion), occlusion of saphenous vein grafts and restenosis after successful coronary angioplasty. Aspirin acts by inhibiting the enzyme cyclo-oxygenase, thus limiting the formation of

Which "internal market"?

Abstract: There are two potential types of “internal markets”. In Type I, the patient is treated only by “contracted” providers while in Type II, he/she is free to choose a provider. The rhetoric of Working for Patients is Type II while the practice is Type I. Type I market with its contracting concept is a pernicious version of the line relationship that existed in the past between health authorities and provider units. The ethos of the NHS is best suited to the Type II market which is similar to the market that operates in higher education, another public service.