PubMed Health⌕ Search

Biomedical subjects

William R Clarke

Publications and source records attributed to William R Clarke.

15 recordsLinked to original sources

Feasibility of acute clinical trials during aerial interhospital transfer.

BACKGROUND AND PURPOSE: In rural America, patients are often first seen at a small community hospital and then transferred to a tertiary care center by helicopter for further care. If acute clinical research were feasible during the aerial interhospital transport, more patients might be enrolled in trials at a critical earlier stage. METHODS: Prospective data were collected for all aerial transfers of a university-based helicopter service from April 2005 to January 2006. Flight nurses were educated about stroke research and offered certification and participation. Data collected included patient characteristics and the availability of relatives to provide surrogate consent. RESULTS: All 12 flight nurses completed the institutional review board certification requirements and collected data on 215 transfers. Sixty-one patients had acute stroke or myocardial events (MIs). The median time from symptom onset to helicopter arrival at an outside hospital was 213 minutes (range, 90 to 2135) for ischemic stroke (n=12), 186 (45 to 1332) for intracranial hemorrhage (n=28), and 157 (47 to 1044) for MI (n=21). A relative was available in >74% of those transfers. A trial with a 4-hour window would permit enrollment of 67% of the ischemic strokes, 82% of intracranial hemorrhage cases, and 76% of MI patients. CONCLUSIONS: Clinical trials are feasible during aerial interhospital transport of patients. Flight nurses became successful investigators in clinical research and were exposed to potentially eligible patients with the ability to consent either directly or through surrogates. This approach could improve current clinical trial recruitment in rural areas, as well as permit testing of inflight ancillary interventions to improve outcome during patient transport.

Acute Disease↗

Effects of intraoperative hypothermia on neuropsychological outcomes after intracranial aneurysm surgery.

OBJECTIVE: Subarachnoid hemorrhage and surgical obliteration of ruptured intracranial aneurysms are frequently associated with neurological and neuropsychological abnormalities. We reported that intraoperative cooling did not improve neurological outcome in good-grade surgical subarachnoid hemorrhage patients, as assessed by the Glasgow Outcome Scale score or other neurological and functional measures (National Institutes of Health Stroke Scale, Rankin Disability Scale, Barthel Activities of Daily Living). We now report the results of neuropsychological testing in these patients. METHODS: A total of 1,001 patients who bled < or = 14 days before surgery were randomly assigned to intraoperative hypothermia (t = 33 degrees C) or normothermia (37 degrees C). Outcome was assessed approximately 3 months after surgery. Patients underwent the Benton Visual Retention, Controlled Oral Word Association, Rey-Osterrieth Complex Figure, Grooved Pegboard, and the Trail Making tests. T-scores for each test were calculated from normative data. T-scores were averaged to calculate a Composite Score. A test result (or the Composite Score) was considered "impaired" if the T-score was two or more standard deviations below the norm. A Mini-Mental State Examination was also performed. RESULTS: Neurological outcome data were available in 1,000 patients. Sixty-one patients died. Of the 939 survivors, 873 completed 3 or more tests (exclusive of the Mini-Mental State Examination). Patients with poor neurological outcomes were less likely to complete testing; only 3.9% of Good Outcome (Glasgow Outcome Scale score = 1) patients were untested, compared with 38.6% of patients with Glasgow Outcome Scale scores of 3 and 4. There were no prerandomization demographic differences between the two treatment groups. For hypothermic patients, 16.8% were impaired from their Composite Score versus 20.0% of patients in the normothermic group (p = 0.317). For patients in the hypothermic group, 54.5% were impaired on at least one test, compared with 55.5% of patients in the normothermic group (p = 0.865). Similar results were seen in patients with baseline WFNS scores = I. Mini-Mental State Examination scores in the hypothermic and normothermic groups were 27.4 +/- 3.8 and 26.8 +/- 4.5, respectively. INTERPRETATION: This is the largest prospective evaluation of neuropsychological function after subarachnoid hemorrhage to date. Testing was completed in a high fraction of patients, demonstrating the feasibility of such testing in a large trial. However, the frequent inability to complete testing in poor-outcome patients suggests that testing may be best used to refine outcome assessments in good-grade patients. Many patients showed impairment on at least one test, with global impairment present in 17 to 20% of patients (18-21% of survivors). This was true even among the patients with the best preoperative condition (WFNS = 1). There was no difference in the incidence of impairment between hypothermic and normothermic groups.

Aged↗

Blood pressure as an independent prognostic factor in acute ischemic stroke.

BACKGROUND AND PURPOSE: Blood pressure is elevated in most patients during acute ischemic stroke, but the prognostic significance of this is unclear as the current data yield conflicting results. METHODS: Admission blood pressure from the 1281 patients in the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) was analyzed for prognostic significance as well as the risk of hemorrhagic transformation. We also examined weighted-average blood pressure over seven days, and the impact of a 30% change in blood pressure in 24 hours. Patients with severe hypertension were excluded from the TOAST trial. RESULTS: Increasing systolic blood pressure (SBP) on admission, but not diastolic (DBP) or mean arterial pressure (MAP) was predictive of poor outcome, but this effect was not significant after adjustment for other know prognostic factors. Increasing weighted-average SBP and MAP over seven days were predictive for poor outcome, but a 30% change in blood pressure over 24 hours was not. CONCLUSIONS: Admission blood pressure is not an independent prognostic factor in acute ischemic stroke, but the weighted-average of SBP and MAP over seven days probably does have predictive value with higher values having a worse prognosis. A prospective trial of blood pressure control during acute stroke is needed.

Blood Pressure↗

Mild intraoperative hypothermia during surgery for intracranial aneurysm.

BACKGROUND: Surgery for intracranial aneurysm often results in postoperative neurologic deficits. We conducted a randomized trial at 30 centers to determine whether intraoperative cooling during open craniotomy would improve the outcome among patients with acute aneurysmal subarachnoid hemorrhage. METHODS: A total of 1001 patients with a preoperative World Federation of Neurological Surgeons score of I, II, or III ("good-grade patients"), who had had a subarachnoid hemorrhage no more than 14 days before planned surgical aneurysm clipping, were randomly assigned to intraoperative hypothermia (target temperature, 33 degrees C, with the use of surface cooling techniques) or normothermia (target temperature, 36.5 degrees C). Patients were followed closely postoperatively and examined approximately 90 days after surgery, at which time a Glasgow Outcome Score was assigned. RESULTS: There were no significant differences between the group assigned to intraoperative hypothermia and the group assigned to normothermia in the duration of stay in the intensive care unit, the total length of hospitalization, the rates of death at follow-up (6 percent in both groups), or the destination at discharge (home or another hospital, among surviving patients). At the final follow-up, 329 of 499 patients in the hypothermia group had a Glasgow Outcome Score of 1 (good outcome), as compared with 314 of 501 patients in the normothermia group (66 percent vs. 63 percent; odds ratio, 1.14; 95 percent confidence interval, 0.88 to 1.48; P=0.32). Postoperative bacteremia was more common in the hypothermia group than in the normothermia group (5 percent vs. 3 percent, P=0.05). CONCLUSIONS: Intraoperative hypothermia did not improve the neurologic outcome after craniotomy among good-grade patients with aneurysmal subarachnoid hemorrhage.

Bacteremia↗

Test-retest of self-reported exposure to artificial tanning devices, self-tanning creams, and sun sensitivity showed consistency.

OBJECTIVE: Exposure to ultraviolet radiation has consistently been linked to an increased risk of melanoma. Epidemiologic studies are susceptible to measurement error, which can distort the magnitude of observed effects. Although the reliability of self-report of many sun exposure factors has been previously described in several studies, self-report of use of artificial tanning devices and self-tanning creams has been less well characterized. STUDY DESIGN AND METHODS: A mailed survey was re-administered 2-4 weeks after completion of the initial survey to 76 randomly selected participants in a case-control study of melanoma. Cases and controls were individuals diagnosed in 1999 and 2000 who were ascertained from the Iowa Cancer Registry in 2002. We assessed the consistency of self-reported use of sunlamps and self-tanning creams, sun sensitivity, and history of sunburns. RESULTS: There was substantial reliability in reporting the use of sunlamps or self-tanning creams (cases: Kappa (kappa)=1.0 for both exposures; controls: kappa=0.71 and 0.87, respectively). kappa estimates of 0.62-0.78 were found for overall reliability of several sun sensitivity factors. CONCLUSION: Overall, the survey instrument demonstrated substantial reproducibility for factors related to the use of sunlamps or tanning beds, self-tanning creams, and sun sensitivity factors.

Adult↗

Can we predict early recurrence in acute stroke?

BACKGROUND: The prevention of early recurrent stroke, which worsens outcomes after a cerebral infarction, is a major objective for acute stroke therapy. The ability to predict which patients are at risk for early recurrence would be useful for both the management and design of clinical trials. METHODS: Using the prospective database with the 1,266 stroke patients admitted in the TOAST study, we analyzed all the patients who had suffered either a transient ischemic attack (TIA) or a recurrent stroke within 3 months after stroke, and their possible association with 20 selected clinical variables. Both univariate and stepwise regression analyses were performed. RESULTS: Sixty-two patients (4.9%) had a second stroke, and 47 patients (3.7%) had at least one TIA. No particular high-risk period was observed. Early recurrent stroke was associated with the large artery atherosclerosis subtype. A prior history of TIA increased the odds for recurrent stroke (OR = 2.52; 1.16-5.46) or poststroke TIA (OR = 3.46; 1.59-7.48). In addition, patients who had a TIA after the stroke had a 17% chance of having an early recurrent stroke, as compared with 4.4% among those that did not (p = 0.001). CONCLUSION: Our present ability to identify patients at risk for early recurrence based on baseline clinical features remains limited. While the presence of TIA before or after the stroke denotes a subgroup of acute stroke patients at higher risk for early recurrence in the first 3 months, no other factors reliably identify high-risk patients.

Acute Disease↗

The Carotid Occlusion Surgery Study.

The St. Louis Carotid Occlusion Study demonstrated that ipsilateral increased O2 extraction fraction (OEF) (Stage II hemodynamic failure) measured by positron emission tomography (PET) is a powerful independent risk factor for subsequent stroke in patients with symptomatic complete carotid artery (CA) occlusion. The ipsilateral ischemic stroke rate at 2 years has been shown to be 5.3% in 42 patients with normal OEF and 26.5% in 39 patients with increased OEF (p = 0.004). In patients in whom hemispheric symptoms developed within 120 days, the 2-year ipsilateral stroke rates were 12% in 27 patients with normal OEF and 50% in 18 patients with increased OEF. Previous PET studies have demonstrated that anastomosis of the superficial temporal artery (STA) to a middle cerebral artery (MCA) cortical branch can restore OEF to normal. The authors discuss the undertaking of a study that will test the hypothesis that STA-MCA anastomosis, when combined with the best medical therapy, can reduce ipsilateral ischemic stroke by 40% at 2 years in patients with symptomatic internal CA occlusion and Stage II hemodynamic failure occurring within 120 days after surgery. Only patients with increased OEF distal to a symptomatic occluded CA will be randomized to surgery or medical treatment. The primary endpoint will be all strokes and death occurring between randomization and the 30-day postoperative cut off (with an equivalent period in the nonsurgical group), as well as subsequent ipsilateral ischemic stroke developing within 2 years. It is estimated that 186 patients will be required in each group. Assuming that 40% of PET scans will demonstrate increased OEF, this will require enrolling 930 clinically eligible individuals.

Anticoagulants↗

Effectiveness of a nationally implemented smoking cessation guideline on provider and patient practices.

BACKGROUND: The Agency for Health Care Policy and Research (AHCPR) smoking cessation guideline outlines a set of recommendations for physicians to follow in daily practice. However, the effectiveness of this guideline has not been reported. The goal of this project was to evaluate the effect of the AHCPR smoking cessation guideline on provider practices with smokers and on patient smoking rates. METHODS: Patient survey and chart review data from 138 Veterans Administration (VA) acute care medical centers with outpatient facilities were examined. Data were available from both sources in 1996, 1997, and 1998. At the midpoint of this period (1997), the VA recommended the AHCPR smoking cessation clinical practice guideline for implementation throughout the VA healthcare system. RESULTS: From 1996 to 1998, both the chart audit and the patient survey showed a significant increase in the percentage of patients in the VA who were counseled about smoking and a significant decrease in the percentage of patients who smoke. CONCLUSIONS: Because the VA tied the guideline implementation to report cards and other performance-enhancing measures, guideline adherence may have been maximized in this setting. These findings suggest that healthcare systems should take an integrated approach to guideline implementation.

Adult↗

Acute pain treatment for older adults hospitalized with hip fracture: current nursing practices and perceived barriers.

This article examines acute pain management practices for patients 65 years of age and older who were hospitalized during 1999 for hip fracture. Data were collected from the medical records of patients (N = 709) admitted to 12 hospitals in the Midwest and from questionnaires on pain practices completed by nurses (N = 172) caring for these patients. The major variables examined were (1). pharmacological and nonpharmacological treatments for acute pain in hospitalized elders, (2). nurses' perceived stage of adoption for avoiding meperidine use and for administering analgesics around-the-clock, and (3). nurses' perceived barriers to optimal treatment of acute pain in elders. Acetaminophen was the most frequently administered analgesic, but administered doses were far less than the maximum daily recommended dose. More than one third (39%) of the nurses reported that they always avoided the use of meperidine, and over half reporting avoiding its use sometimes. However, the majority of patients (56.8%) received at least one dose of meperidine, even though evidence suggests that other analgesic agents are more appropriate for treatment of acute pain in elders. Only 27% of patients received patient-controlled analgesia, and only 22.3% of patients received around-the-clock administration during the first 24 hours after admission of analgesics that had been ordered on a prn basis. The majority of nurses were aware that around-the-clock administration of analgesics was preferable, but only 33.7% were persuaded (believed) that this method should be used. Intramuscular injection was used for 52.2% of patients, even though this route is not recommended for older adults. The most frequently used nonpharmacological intervention was repositioning, followed by use of pressure relief devices and cold application. Nurses reported difficulty contacting physicians and difficulty communicating with them about type and/or dose of analgesics as the greatest barriers to pain management. Findings from this multi-site study show that active and focused "translation" interventions are needed to promote adoption of evidence-based acute pain management practices by health care providers.

Acute Disease↗

Health-related quality of life in Gulf War era military personnel.

The Gulf War's impact on veterans' health-related quality of life (HRQL) remains unclear. The authors examined the HRQL of military personnel deployed to the Gulf War Theater compared with those not deployed. In 1995-1996, a structured, population-based telephone survey was conducted 5 years postconflict among a cohort originally from Iowa on active duty during the conflict. The sample included 4,886 eligible subjects stratified by deployment and military status and proportionately distributed within five substrata. The Medical Outcome Study Short Form-36 (SF-36) assessed HRQL, and multivariable linear regression identified pre- and perideployment risk factors. A total of 3,695 respondents (76%) participated. Nondeployed participants reported excellent health more often than deployed participants (31% vs. 21%, p < 0.01). SF-36 scores for deployed participants were poorer than those for nondeployed controls across all health domains. Modifiable factors such as smoking and military preparedness, and other factors such as predeployment physical and mental health morbidity, were independent risk factors for poorer HRQL after deployment. Deployed veterans reported slightly poorer HRQL even after the authors adjusted for other risk factors. Further investigation of factors influencing postdeployment HRQL is needed. Routine collection of health information by using standardized instruments pre- and perideployment should be implemented.

Adult↗

Methodologic issues in a population-based health survey of Gulf War veterans.

This report describes the principal methods used in the development, conduct, and analysis of the research study "Health Assessment of Persian Gulf War Veterans from Iowa" (Iowa Gulf War Study). The methods presented include an outline of the organizational structure, study timeline, hypotheses, outcome definitions, and study design. Adhering to a strict timeline, the study protocol and instruments were developed, and a stratified sample of 3,695 military personnel (76% participation) was located and surveyed by structured telephone interview. The study tracked personnel from all service branches residing nationally and internationally, including those discharged from service. This study required development and implementation of methods appropriate to analysis of data collected in a complex sampling framework and methodological procedures to ensure scientific rigor in a highly public and politicized environment. Statistical analyses were conducted on a priori health outcomes and required development of methods to compute Cochran-Mantel-Haenszel adjusted rate differences. This environment facilitated rapid implementation, critique by scientific and public advisors, a high participation rate, and rapid publication.

Adult↗

Physician knowledge, attitudes and practices regarding a widely implemented guideline.

RATIONALE, AIMS AND OBJECTIVES: Although clinical practice guidelines have been promoted widely, there is considerable concern that physicians have not incorporated them into their practice. Models suggest that a 'knowledge-attitude-behaviour' sequence is important in modifying physician practice patterns. To address this, we examined physicians' knowledge of, attitudes towards and compliance with a widely implemented guideline - the Agency for Health Care Policy and Research (AHCPR) smoking cessation guideline. METHODS: A survey was mailed to a random sample of physicians at 128 veterans health administration facilities, which had implemented the guideline 2 years previously. RESULTS: Completed surveys were received from 879 physicians (50.3 response rate). Only 26 of physicians reported receiving a copy or summary of the guideline, 44 reported little or no familiarity with it, 42 did not know if they agreed with it, 40 did not know if they complied with it and 46 did not know if it was effective. However, a high percentage of physicians reported that they always or usually explain the health risks of smoking (86) and that they always or usually suggest that their smoking patients stop (94). CONCLUSIONS: In spite of little familiarity with the guideline, the responding physicians reported practice patterns consistent with adherence to it. Knowledge is only one of a spectrum of barriers that affects physician adherence to guidelines. There are numerous opportunities for health care organizations to overcome the barriers to physician adoption of clinical practice guidelines in their day-to-day practice.

Adult↗

Evidence-based assessment of acute pain in older adults: current nursing practices and perceived barriers.

OBJECTIVES: To report data on current nurse practice behaviors related to evidence-based assessment of acute pain in older adults, perceived stage of adoption of pain assessment practices, and perceptions of barriers to optimal assessment in this population. METHODS: Medical records from 709 older adult patients hospitalized with hip fractures from 12 acute care settings were abstracted for nurse assessment practices during the first 72 hours after admission. Questionnaires sent to nurses on study units regarding perceived stage of adoption and barriers to assessment in older adults. RESULTS: Data revealed several areas in which pain assessment practices were not optimal. Pain was not routinely assessed every 4 hours, and pain location was assessed even less frequently. Pain behaviors were assessed more in patients with a diagnosis of dementia compared to those without dementia, but the frequency of pain behavior assessments was low. Pain was not routinely assessed within 60 minutes of administering an analgesic. Nurses reported not using optimal pain assessment practices even when they were aware of and persuaded that those practices were desirable. In addition, nurses reported that difficulty communicating with patients created the greatest challenge in managing pain. CONCLUSIONS: Our data suggest that pain is not being assessed and reassessed in a manner that is consistent with current practice recommendations in older adult patients with pathologic processes that highly suggest the presence of acute pain.

Aged↗