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D Oakes

Publications and source records attributed to D Oakes.

At least 37 records · Page 2Linked to original sources
PubMed1997

Nurse-physician collaboration and satisfaction with the decision-making process in three critical care units.

OBJECTIVE: To assess and compare levels of nurse-physician collaboration and satisfaction with the decision-making process as reported by critical care nurses, resident physicians (residents), and attending physicians (attendings) in making decisions to transfer individual patients out of the critical care unit, and to assess if satisfaction predicts nurse retention. DESIGN: Longitudinal descriptive correlational study using self-reporting instruments. SETTINGS: A university hospital's surgical ICU, a community teaching hospital's medical ICU, and a community hospital's mixed ICU. SUBJECTS: Eighty-one nurses, 23 residents, and 37 attendings from the surgical ICU; 44 nurses and 51 residents from the medical ICU; 25 nurses and 45 attendings from the community hospital's ICU, reporting on the transfers of 473, 465, and 494 patients, respectively. MAIN OUTCOME MEASURES: Healthcare providers' reported levels of collaboration and satisfaction with the decision-making process, the correlations between collaboration and satisfaction, and nurse retention. RESULTS: Nurses and physicians within sites (except attendings from the surgical ICU) reported similarly moderate amounts of collaboration, but nurses reported less satisfaction with decision making than did physicians in all sites. Collaboration was related to satisfaction with decision making for all providers, but more strongly for nurses. The strength of the relationship for nurses was similar in all sites. Nurses' satisfaction with decision making did not predict their retention. CONCLUSIONS: Collaboration between nurses and physicians is a more important component of satisfaction with decision making for nurses than for physicians. Any interventions to change the amount of collaboration in practice must take account of this difference.

Adult↗
PubMed1995

Multiple time scales in survival analysis.

In some problems in survival analysis there may be more than one plausible measure of time for each individual. For example mileage may be a better indication of the age of a car than months. This paper considers the possibility of combining two (or more) time scales measured on each individual into a single scale. A collapsibility condition is proposed for regarding the combined scale as fully informative regarding survival. The resulting model may be regarded as a generalization of the usual accelerated life model that allows time-dependent covariates. Parametric methods for the choice of time scale, for testing the validity of the collapsibility assumption and for parametric inference about the failure distribution along the new scale are discussed. Two examples are used to illustrate the methods, namely Hyde's (1980) Channing House data and a large cohort mortality study of asbestos workers in Quebec.

Aged↗
PubMed1995

A randomized, double-blind, placebo-controlled trial of systemically administered interferon-alpha, -beta, or -gamma in combination with cryotherapy for the treatment of condyloma acuminatum.

One hundred fifty-two patients were enrolled in a study to evaluate 3 interferon (IFN) preparations used in combination with cryotherapy for treatment of anogenital warts. Subjects received subcutaneous injections (2 x 10(6) units/m2) of IFN-alpha n1, -beta, -gamma or placebo 3 times a week for 6 weeks and cryotherapy with liquid nitrogen. Subjects were followed < or = 1 year. Among patients followed > or = 12 weeks, two-thirds had a complete response. No significant differences in rates of complete response (P = .37) or reappearance of a wart at the initial site (P = .20) were noted among the treatment groups. However, patients who received IFN-beta or -gamma developed new warts at a significantly lower frequency (P = .02). IFN administration was associated with side effects but was well tolerated. IFN-beta was the least toxic of the 3 preparations and had the best therapeutic ratio.

Adult↗
PubMed1992

Hypolipidemic effect of type Ia antiarrhythmic agents in postinfarction patients.

BACKGROUND: Elevated levels of cholesterol and apoprotein B (apo B), the essential carrier protein for low density lipoprotein, are major lipid risk factors for premature coronary disease. Antiarrhythmic agents are frequently prescribed to patients with coronary heart disease and associated cardiac arrhythmias. As part of another study, we retrospectively investigated the effect of antiarrhythmic agents on blood lipids. METHODS AND RESULTS: The study population consisted of 1,567 postinfarction patients on whom we prospectively collected serial blood samples for lipid and apoprotein determinations and recorded the concomitant medications the patients were receiving at three follow-up time periods. The lipids, analyzed at a central core laboratory, included total cholesterol, triglycerides, high density lipoprotein cholesterol (HDL C), and apoproteins A-I (apo A-I), A-II (apo A-II), and apo B. The difference in the group mean lipid values for patients receiving and not receiving type Ia antiarrhythmic agents (quinidine, procainamide, and disopyramide) was evaluated by the two-sample t test, and multiple linear regression analyses were performed to adjust for relevant covariates. Patients using type Ia antiarrhythmic agents at the 30-month postinfarction contact (n = 76) had 8.6% lower cholesterol (p less than 0.003), 22.3% lower triglycerides (p less than 0.0002), 6.2% lower apo A-I (p = 0.02), 10.1% lower apo A-II (p less than 0.001), and 12.7% lower apo B (p less than 0.0001) levels than patients not on these medications (n = 1,491). These lower lipid levels were found after adjustment for age, sex, diabetes, smoking status, concomitant medications, and a variety of clinical factors relating to the severity of the coronary disease process. The HDL C levels were similar in those receiving and not receiving type Ia agents. CONCLUSIONS: Patients on type Ia antiarrhythmic agents had significantly and meaningfully lower cholesterol, triglyceride, apo A-II, and apo B levels than patients not receiving these agents. The mechanism of this hypolipidemic effect is undefined, but the mechanism may be related to an alteration by these agents of ionic membrane currents at the hepatocyte level.

Anti-Arrhythmia Agents↗
PubMed1992

Markers of dopamine metabolism in Parkinson's disease. The Parkinson Study Group.

We used two analytic methods (a multichannel coulometric electrode array with high-performance liquid chromatography, and gas chromatography-mass spectrophotometry) to measure CSF dopamine (DA) and its metabolites in mildly affected, unmedicated subjects with Parkinson's disease (PD). The mean (+/- SD) concentration of homovanillic acid (HVA), the most abundant product of DA turnover, was 164.57 +/- 95.05 nM. As sequential aliquots of CSF were collected from the first to 23rd ml, CSF HVA concentration almost doubled. After HVA, 3-O-methyldopa (3-O-MD) was the next most abundant compound. The summed concentrations of 3-O-MD, 3,4-dihydroxyphenylacetic acid, 3-methoxytyramine, DA, DA-3-sulfate, homovanillol, and levodopa (LD) amounted to 12.6% of HVA. Concentrations of the DA metabolites did not correlate to a variety of indices of PD severity. The presence of LD and 3-O-MD may be indicators of DA synthesis and possibly could reflect compensatory processes among surviving dopaminergic neurons of the PD brain.

Aged↗
PubMed1991

Effects of diltiazem on long-term outcome after acute myocardial infarction in patients with and without a history of systemic hypertension. The Multicenter Diltiazem Postinfarction Trial Research Group.

The effect of diltiazem on long-term outcome in patients with acute myocardial infarction with and without a history of systemic hypertension was investigated in 2,466 patients using the Multicenter Diltiazem Postinfarction Trial data-base. The baseline variables were comparable in the diltiazem and placebo-treated patients within the groups with and without hypertension. The initial 60-mg dose of diltiazem was associated with a significant (p less than 0.001) but modest (3%) reduction in blood pressure and heart rate in both groups with and without hypertension. Univariate and multivariate analyses revealed a meaningful overall reduction in first recurrent cardiac events (cardiac death or nonfatal reinfarction, whichever occurred first) and cardiac death in patients with hypertension treated with diltiazem compared with results in those treated with placebo. Similar effects were not observed in patients without a history of hypertension. When first recurrent cardiac events were used as the end point, the diltiazem:placebo hazard ratio (95% confidence limits) was 0.77 (0.58, 1.01) for the total hypertension group, and 0.67 (0.47, 0.96) and 1.32 (0.83, 2.10) for patients with hypertension with and without pulmonary congestion during the acute infarction, respectively. Similar results were observed using cardiac death as the end point. Beta blockers had a negligible effect on the hypertension-diltiazem relation. These findings suggest that diltiazem may exert a long-term beneficial effect in most patients with hypertension who do not have pulmonary congestion during an acute infarction, and a detrimental effect in the minority who have pulmonary congestion.

Adult↗
PubMed1991

Electrocardiographic subset analysis of diltiazem administration on long-term outcome after acute myocardial infarction. The Multicenter Diltiazem Post-Infarction Trial Research Group.

The effect of diltiazem on long-term outcome after acute myocardial infarction (AMI) was assessed in 2,377 patients enrolled in the Multicenter Diltiazem Post-Infarction Trial and subsequently followed for 25 +/- 8 months. The study population included 855 patients (36%) with at least 1 prior AMI before the index infarction and 1,522 patients (64%) with a first AMI, of whom 409 (27%) had a first non-Q-wave AMI, 664 (44%) a first inferior Q-wave AMI, and 449 (30%) a first anterior Q-wave AMI. This post hoc analysis revealed that, among patients with first non-Q-wave and first inferior Q-wave AMI, there were fewer cardiac events during follow-up in the diltiazem than in the placebo group, and that the reverse was true for patients with first anterior Q-wave AMI or prior infarction. The diltiazem:placebo Cox hazard ratio (95% confidence limits) for the trial primary end point (cardiac death or nonfatal reinfarction, whichever occurred first) was: first non-Q-wave AMI-0.48 (0.26, 0.89); first inferior Q-wave AMI-0.66 (0.40, 1.09); first anterior Q-wave AMI-0.82 (0.51, 1.31); and prior AMI-1.11 (0.85, 1.44). Use of cardiac death alone as an end point gave an even more sharply focused treatment difference: first non-Q-wave AMI-0.46 (0.18, 1.21); first inferior Q-wave AMI-0.53 (0.27, 1.06); first anterior Q-wave AMI-1.28 (0.68, 2.40); prior infarction-1.26 (0.90, 1.77). Further analysis revealed that these differences in the effect of diltiazem in large part reflected the different status of the 4 electrocardiographically defined subsets in terms of left ventricular function.(ABSTRACT TRUNCATED AT 250 WORDS)

Diltiazem↗
PubMed1990

The prognostic significance of first myocardial infarction type (Q wave versus non-Q wave) and Q wave location. The Multicenter Diltiazem Post-Infarction Research Group.

The prognostic significance of the type of first acute myocardial infarction (Q wave versus non-Q wave) and Q wave location (anterior versus inferoposterior) was determined from a multicenter data base involving 777 placebo-treated patients who were participants in the Multicenter Diltiazem Post-Infarction Trial. There were 224 patients (29%) with a non-Q wave infarction, 326 (42%) with an inferoposterior Q wave infarction and 227 (29%) with an anterior Q wave infarction. Mean left ventricular ejection fraction was significantly (p less than 0.001) lower in patients with an anterior Q wave infarction than in the other two groups (anterior Q wave 0.39; inferior Q wave 0.52; non-Q wave 0.53). Nevertheless, the total cardiac mortality rate during the follow-up period (average 25 months per patient) was only marginally higher (p = 0.42) in the anterior Q wave group (8.4%) than in the other two groups (inferoposterior Q wave 7.1%; non-Q wave 6.3%). The total first recurrent cardiac event was somewhat higher (p = 0.08) in the anterior Q wave group (18.1%) than in the other two groups (inferoposterior Q wave 11.7%; non-Q wave 15.6%). Survivorship analyses extending over 3 years revealed that electrocardiographic classification of the type of first infarction and Q wave location did not make significant independent contributions to the risk of postinfarction cardiac death or first recurrent cardiac event, either before or after adjustment for baseline clinical variables.

Adult↗
PubMed1990

Prognostic significance of nonfatal myocardial reinfarction. Multicenter Diltiazem Postinfarction Trial Research Group.

In most risk stratification and intervention postinfarction trials, cardiac mortality is used as the major outcome end point either alone or in combination with nonfatal reinfarction. However, the independent risk carried by nonfatal reinfarction for subsequent cardiac death has not been quantified. The prognostic significance of nonfatal reinfarction was determined from the multicenter diltiazem trial data base of 1,234 patients treated with placebo followed up for 1 to 4 years after acute myocardial infarction. One hundred sixteen patients had at least one nonfatal reinfarction, 14 (12%) of whom subsequently experienced cardiac death. Of the remaining 1,118 patients without nonfatal reinfarction, 110 (9.8%) experienced cardiac death. Compared with event-free patients, patients with nonfatal reinfarction were more likely (p less than 0.05) to be women, to have had an infarction before their index event and to have had prior cardiac-related symptoms. Cox survivorship analyses, using pertinent baseline clinical variables along with nonfatal reinfarction as a time-dependent predictor variable, revealed that nonfatal reinfarction carried a significant and independent risk for subsequent cardiac mortality (hazard ratio 3.0, p = 0.002), which was greater than that carried by other significant predictor variables (New York Heart Association functional class, pulmonary congestion on chest radiograph, blood urea nitrogen level, predischarge Holter-recorded ventricular premature complexes and radionuclide ejection fraction). The cardiac mortality risk associated with nonfatal reinfarction was further increased in patients whose index event was their first infarction (hazard ratio 5.4, p = 0.0006). Thus, nonfatal reinfarction carries a strong, significant and independent risk for subsequent cardiac death in patients surviving an acute myocardial infarction.

Adult↗
PubMed1990

Treatment of condyloma acuminatum with three different interferon-alpha preparations administered parenterally: a double-blind, placebo-controlled trial.

One hundred seventy-eight patients were enrolled in a placebo-controlled trial to evaluate three interferon-alpha preparations administered parenterally for the treatment of condyloma acuminatum. When all interferon groups were combined and compared with placebo, interferon recipients had greater rates of complete, 75%, 50%, and 25% lesion resolution than did placebo recipients (P = .21, P = .14, P = .02, and P = .02, respectively). Rates of lesion resolution were higher among women than among men, and women were more likely than men to respond to interferon. Virologic measurements in paired lesion biopsies did not correlate with interferon treatment or disease outcome. Although interferon toxicity was observed frequently, no participant withdrew from the study because of side effects, and dosage alterations were not required. Parenterally administered interferon-alpha is more effective than placebo in treating condyloma acuminatum, although rates of complete response are low. Different regimens, including combination therapy, should be evaluated for treatment of this common sexually transmitted disease.

Adult↗
PubMed1989

A controlled clinical trial of baclofen as protective therapy in early Huntington's disease.

We carried out a controlled clinical trial to examine the potential of baclofen to slow the functional decline of patients with early Huntington's disease (HD). The basis of the trial was: (1) the hypothesis that excitatory amino acid neurotransmission mediates the neuronal degeneration of HD, (2) preclinical evidence that baclofen retards corticostriatal release of glutamate and aspartate, and (3) reports that baclofen produces short-term clinical benefits in some HD patients. Sixty patients with early HD were randomized to chronic baclofen, 60 mg/day, or placebo treatments and followed systematically for up to 42 months. Total functional capacity was not favorably influenced by baclofen treatment. Factors that contributed, although nonsignificantly, to a more rapid rate of total functional capacity decline included younger age (less than 35 years), earlier stage (stage I) of illness, paternal inheritance of the HD gene, and baclofen treatment. Our patients declined at a pace slower than that observed in other prospective studies, a finding likely due to selection criteria, avoidance of neuroleptic therapy, and strong psychosocial support.

Adolescent↗
PubMed1989

The interaction between diltiazem and left ventricular function after myocardial infarction. Multicenter Diltiazem Post-Infarction Research Group.

The interactions between diltiazem and three parameters of left ventricular function using cardiac death as the end point were investigated in 2,466 patients, aged 25-75 years, who were involved in the long-term diltiazem postinfarction trial. Indexes of left ventricular function included pulmonary congestion on chest x-ray, acute anterolateral Q wave myocardial infarction on electrocardiogram, and radionuclide ejection fraction. Pulmonary congestion and acute anterolateral infarction had significant (p less than 0.01) interactions with treatment allocation, and the third variable, ejection fraction, showed a similar trend (p less than 0.1). There was a diltiazem-related reduction in cardiac death (Cox hazard ratio, 0.76-0.86) for each of the parameters reflecting good ventricular function, and a significant diltiazem-related increase in cardiac death (Cox hazard ratio, 1.52-1.85) for each of the parameters associated with impaired function. Three-factor interactions highlighted the extremes of the favorable and adverse effects of diltiazem in subsets with unimpaired and impaired left ventricular function. These findings permit more appropriate selection of patients for the safe and effective administration of diltiazem to postinfarction patients.

Adult↗
PubMed1988

Mortality of workers at acetylene production plants.

To reduce the risk of explosion oxyacetylene cylinders are filled with a spongy mass, acetone is added to saturate the mass, and acetylene is pumped into the cylinder. The first cylinders manufactured before 1936 used a kapok filling topped off with about 16 oz of crocidolite asbestos, with a metal gauze thimble inserted to reduce risk of flash back. Cylinders must be examined annually. The use of crocidolite ceased in 1972 and other fillings have been adopted since 1970; kapok cylinders now constitute less than 5% of the total stock. To assess possible hazards, a mortality study of workers first employed between 1935 and 1975 and followed up to December 1984 was undertaken. Simulation tests showed low concentrations of asbestos in the air even in the earliest period. The population studied consisted of 370 workers at the Bilston plant in the West Midlands, 611 at the 14 other plants in England and Wales, and 120 in Scotland. No deaths occurred from mesothelial tumours but there was an excess of deaths from cancer, particularly lung cancer, cancer of the stomach, and cancer of the pancreas, the latter accounting for eight deaths. Risks appeared to be concentrated at the Bilston plant. The importance of these findings is discussed.

Acetylene↗
PubMed1988

Exercise-induced hypotension in a male population. Criteria, causes, and prognosis.

The objective of this study was to demonstrate the causes, optimal definition, and predictive value of exercise-induced hypotension occurring during treadmill testing. This study included all patients referred for clinical reasons to the Long Beach Veterans Administration Medical Center treadmill laboratory and then followed for a 2-year period for cardiac events. The population consisted of 2,036 patients who underwent testing from April 4, 1984, to May 7, 1987, 131 of whom exhibited exercise-induced hypotension (6.4%). We found that exercise-induced hypotension is usually related to myocardial ischemia or myocardial infarction, is best defined as a drop in systolic blood pressure during exercise below the standing preexercise value, and indicates a significantly increased risk for cardiac events (3.2-fold, p less than 0.005). This increased risk was not found in those having no previous myocardial infarction or no signs or symptoms of ischemia during the exercise test, and the increased risk was also not found in those undergoing a treadmill test within 3 weeks after a myocardial infarction. Exercise-induced hypotension appeared to be reversed by revascularization procedures, but confirmation of a beneficial effect on survival requires a randomized trial. The clinical importance of this study is that we have demonstrated that a drop in systolic blood pressure below standing preexercise values during treadmill testing indicates an increased risk for cardiac events except in certain subsets of patients.

Adult↗
PubMed1988

Treatment of condyloma acuminatum with three different interferons administered intralesionally. A double-blind, placebo-controlled trial.

STUDY OBJECTIVE: To determine the efficacy and toxicity of intralesionally administered interferons in the treatment of condyloma acuminatum. DESIGN: Randomized, double-blind, and placebo-controlled study. SETTING: Outpatient clinics at university medical centers. PATIENTS: Seventy-nine patients with biopsy-proved condyloma acuminatum that was refractory to conventional therapy were enrolled in the study. INTERVENTIONS: Alpha-2b, alpha-nl-, and beta-interferons were used. One wart on each patients was injected three times per week for 4 weeks with either 1 x 10(6) units of interferon or placebo. MEASUREMENTS AND MAIN RESULTS: Forty-seven percent of warts injected with interferon resolved completely, compared with 22% of placebo-injected warts (P = 0.009). In addition, more recipients of interferon had a complete resolution of uninjected lesions. No differences in rates of response were noted among the different interferon groups. Approximately one third of interferon-injected warts recurred, compared with none of four placebo-injected warts. Intralesionally administered interferon was nontoxic and well tolerated, although transient pain on injection was observed frequently. CONCLUSIONS: Intralesional administration of each of these three interferons appears to be useful in treating condyloma acuminatum. However, the frequent recurrence of disease and the failure of many lesions to resolve indicate that different regimens, such as longer courses of therapy or different routes of administration, should be evaluated to maximize beneficial effects of interferon for treating this common sexually transmitted disease.

Adult↗