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O Boyd

Publications and source records attributed to O Boyd.

At least 19 recordsLinked to original sources
PubMed2006

Dietetic guidelines on food and nutrition in the secondary prevention of cardiovascular disease - evidence from systematic reviews of randomized controlled trials (second update, January 2006).

AIM: To update dietetic guidelines based on systematic review evidence on dietary advice to prevent further events in people with existing cardiovascular disease (CVD) (secondary prevention). METHODS: The Cochrane Library, MEDLINE and EMBASE were comprehensively searched to January 2005 for systematic reviews on aspects of diet and heart health. Reviews were included if they searched systematically for randomized controlled trials relating to diet and secondary prevention of CVD. Each review was critically appraised by at least two members of the UK Heart Health and Thoracic Dietitians Group. The quality and results of each review were discussed and summarized at a group meeting. RESULTS: Evidence-based strategies that reduce cardiovascular events in those with CVD include reduction in saturated fat and substitution with unsaturated fats. Individuals who have suffered a myocardial infarction may also benefit from adopting a Mediterranean type diet and increasing intake of omega 3 fats, but it is not clear whether they are beneficial for all patients with CVD. There is no systematic review evidence to support the use of antioxidant vitamins supplements, low glycaemic index diets, or homocysteine lowering therapies in this group. CONCLUSION: There remains good evidence that reducing saturated fat reduces morbidity in patients with CVD. This advice is consistent for most manifestations of CVD, with the addition of Mediterranean dietary advice and increased omega 3 fats for those who have had a myocardial infarction.

Antioxidants↗
PubMed2004

Cell-free plasma DNA as a prognostic marker in intensive treatment unit patients.

Recent evidence suggests that cell-free plasma DNA has potential use as a prognostic marker in many clinical settings. The aim of the present study was to evaluate the prognostic role of cell-free plasma DNA in the prediction of clinical outcome in intensive treatment unit (ITU) patients. Cell-free plasma DNA was measured by real-time polymerase chain reaction assay for the beta-globin gene and SOFA score, APACHE II score, CRP concentrations, and clinical outcome (duration of stay, ventilation time, and mortality) were noted in 94 patients on admission to the ITU. The median plasma DNA concentration in ITU patients was 5493 GE/mL and this was significantly (P <0.001) higher than the DNA concentration in healthy subjects (1970 GE/mL). DNA concentration demonstrated a significant correlation with serum C-reactive protein (CRP) (r = 0.363) concentration and Sepsis-related Organ Failure Assessment (SOFA) (r = 0.360) score (P <0.001 for both by Pearson correlation) but not with Acute Physiology And Chronic Health Evaluation (APACHE II) score. Patients on ventilation had significantly higher DNA concentrations compared to nonventilated patients (7362 GE/mL versus 4479 GE/mL; P = 0.004). The median DNA concentration in nonsurvivors was 9148 GE/mL, and this was 2.3-fold greater than that in survivors (3921 GE/ml, P <0.001). ROC analysis of the data indicated a sensitivity of 85% and a specificity of 80% when DNA concentration of 6109 GE/mL was taken as a predictor of death. The data suggest that cell-free plasma DNA concentration is potentially useful as a prognostic marker in ITU patients.

Adult↗
PubMed2003

Optimisation of oxygenation and tissue perfusion in surgical patients.

Surgical patients with limited cardiovascular reserve have much worse prognosis than patients with normal hearts. This review identifies 17 randomised controlled clinical trials that have investigated peri-operative therapy designed to increase tissue perfusion in surgical patients, many of whom have limited cardiovascular reserve. Although there are differences which make equating the trials complex, a total of 1974 patients have been enrolled in the studies and the odds ratio for reduction in mortality is 0.45 (95% confidence intervals 0.33-0.60). Further research needs to be undertaken in the identification of patients with limited cardiovascular reserve and for investigating proposed treatment strategies. Despite this, it appears that such patients have improved outcome if they are admitted to intensive care unit pre-operatively and have suitable therapy given to improve tissue oxygen delivery.

Blood Circulation↗
PubMed1999

The oxygen trail: the goal.

Over the last 10 years, there have been great advances in knowledge concerning changes in tissue perfusion and its prognostic implications. Has this translated into improved patient management? We review the clinical trials that have deliberately increased tissue oxygen delivery by increasing cardiac output. We have divided the studies into those that intervene early or those that intervene late in the course of a patient's illness. Although there are methodological problems limiting interpretation of the results, we show a combined odds ratio of a reduction in mortality for the early studies but not for the late studies. We conclude that a treatment policy whereby oxygen delivery is deliberately increased improves patient outcome if it is initiated early, prior to the onset of organ failure.

Cardiac Output↗
PubMed1997

A cost analysis of a treatment policy of a deliberate perioperative increase in oxygen delivery in high risk surgical patients.

OBJECTIVE: To investigate the cost implications of a treatment policy of a deliberate perioperative increase of oxygen delivery in high risk surgical patients. DESIGN: A cost-effectiveness analysis comparing 'protocol' high risk surgical patients in whom oxygen delivery was specifically targeted towards 600 ml/min/m2 with 'control' patients. INTERVENTIONS: In a randomised, controlled clinical trial we previously demonstrated a significant reduction in mortality (5.7% vs 22.2%, p = 0.015) and morbidity (0.68 +/- 0.16 complications vs 1.35 +/- 0.20, p = 0.008) in 'protocol' high risk surgical patients in whom oxygen delivery was specifically targeted towards 600 ml/min per m2 compared with 'control' patients. This current study retrospectively analysed the medical care and National Health Service resource use of each patient in the trial. Departmental purchasing records and business managers were consulted to identify the unit cost of these resources, and thereby the cost of treating each patient was calculated. RESULTS: The median cost of treating a protocol patient was lower than for a control patient (6,525 pounds vs 7,784 pounds) and this reduction was due mainly to a decrease in the cost of treating postoperative complications (median 213 pounds vs 668 pounds). The cost of obtaining a survivor was 31% lower in the protocol group. CONCLUSION: Perioperative increase of oxygen delivery in high risk surgical patients not only improves survival, but also provides an actual and relative cost saving. This may have important implications for the management of these patients and the funding of intensive care.

Clinical Protocols↗
PubMed1996

Gastric tonometry.

Explore the source record for details and available documents.

Acid-Base Imbalance↗
PubMed1996

Enhancement of perioperative tissue perfusion as a therapeutic strategy for major surgery.

Multiple organ dysfunction syndrome (MODS) accounts for most surgical deaths which occur some days postoperatively. Current hypotheses concerning the pathophysiology of MODS place tissue hypoxia and reperfusion as a central feature of the initiation and continuation of the syndrome. Surgical patients are at risk of developing overt and covert tissue hypoxia and hypoperfusion due to anesthetic, surgical, and other factors; and it is known that surgical patients with poor cardiovascular reserve have a worse outcome postoperatively. A number of clinical studies have attempted to intervene early in surgical patients to prophylactically improve tissue perfusion in the perioperative period by augmentation of cardiac output. These studies demonstrate a reduction in mortality and morbidity in these groups of patients. A similar approach has been tried in other groups of critically ill patients, at a later state in the evolution of their illness; these studies have not shown any improvement in outcome. In surgical patients, data show that those with more coexisting pathology and worse cardiac function may benefit most from a treatment approach aimed at improving tissue perfusion; furthermore, this may result in cost savings. The implications for the management of the higher risk surgical patient are obvious. It may no longer be acceptable to undertake surgery in these patients without facilities to monitor and improve cardiac output and tissue perfusion.

Blood Circulation↗
PubMed1995

Sickle cell anemia, right atrial thrombosis, and the antiphospholipid antibody.

We report a patient with sickle cell anemia (homozygous Hb SS) and typical features of sickle chest syndrome but with no response to exchange transfusion. A right atrial thrombus was found, and antiphospholipid antibodies were detected in his blood. He responded to thrombolytic therapy. The relationship between right atrial thrombus and massive pulmonary embolus, and the implications of an additional thrombophilic state in sickle cell disease are discussed.

Adult↗
PubMed1995

A comparison of the efficacy of dopexamine and dobutamine for increasing oxygen delivery in high-risk surgical patients.

Peri-operative increase of oxygen delivery has been shown to reduce mortality in high-risk surgical patients. This study compares the effectiveness of dopexamine and dobutamine when used to increase cardiac output as part of a regimen to increase oxygen delivery. Sixteen surgical patients were randomly allocated to receive either dopexamine or dobutamine, which was increased to a stable dose defined as either oxygen delivery index > 600 ml/min/m2, or tachycardia > 20% above baseline, other dysrhythmias or angina. At this "stable" dose there were significant increases in cardiac index (2.4 +/- 0.2 vs 3.7 +/- 0.3 l/min/m2) and oxygen delivery (380 +/- 73 vs 579 +/- 40 ml/min/m2) in the dopexamine group (P < 0.05); but not the dobutamine group. Five out of eight patients receiving dopexamine and three out of eight receiving dobutamine reached target oxygen delivery. Three dobutamine patients, but no dopexamine patients, had angina or dysrhythmias. In preoperative high-risk surgical patients, dopexamine can allow greater increases in oxygen delivery than dobutamine, due to cardiac effects that limit the dobutamine infusion rate.

Adrenergic beta-Agonists↗
PubMed1995

Follicular fluid levels of midazolam, fentanyl, and alfentanil during transvaginal oocyte retrieval.

OBJECTIVE: To investigate the time course of changes in follicular fluid (FF) concentrations of midazolam (Roche Products Ltd., Welwyn Garden City, United Kingdom), fentanyl (Janssen Pharmaceuticals Ltd., Wantage, United Kingdom), and alfentanil (Janssen Pharmaceuticals Ltd.) during ultrasound-guided transvaginal oocyte collection. STUDY DESIGN: Forty-five patients with tubal infertility were randomized to receive a bolus IV dose of midazolam, fentanyl, or alfentanil for sedation during ultrasound-guided transvaginal oocyte collection. Paracervical block with lignocaine was given for analgesia. Simultaneous blood and FF samples were drawn at 5-minute intervals after the bolus dose for analysis of drug levels. RESULTS: Data were obtained on 15 women receiving midazolam and fentanyl and on 13 women receiving alfentanil. Plasma levels of all agents rose to a peak and then fell in an exponential fashion as was expected. The FF levels of the agents continued to rise significantly to 25 minutes after the bolus dose, although the absolute level was low when compared with the blood level. There were no significant differences in fertilization or pregnancy rates in the three groups, but patient numbers were small. CONCLUSION: We conclude that midazolam, fentanyl, and alfentanil are found in FF after a single IV dose, but further investigation needs to be undertaken to investigate any potential influence on fertilization and implantation rates.

Adult↗