Rationale and design of a comparative effectiveness trial of home- and clinic-based self-management support coaching for older adults with asthma.

Older adults with asthma face numerous barriers to effective self-management and asthma control, and experience worse outcomes than younger asthmatics. Yet, there have been no controlled trials of interventions specifically designed to improve their care and outcomes. Through a multi-stakeholder collaboration (patients, academia, community-based organizations, a state department of health, and an advocacy organization) we developed a multi-component asthma self-management support intervention to address the myriad psychosocial, functional, health status, and cognitive barriers to effective asthma self-management in adults ages 60 and older. We are recruiting 425 New Yorkers in Manhattan and the Bronx for a pragmatic randomized controlled trial with 3 arms: the intervention delivered in primary care settings or in their home, or usual care. In the intervention, care coaches use a novel screening tool to identify the specific barriers to asthma control and self-management they experience. Once identified, the coach and patient choose from a menu of actions to address it. The intervention emphasizes efficiency, flexibility, shared decision making and goal setting, communication strategies appropriate for individuals with limited cognition and literacy skills, and ongoing reinforcement and support. Additionally, we introduced asthma-specific enhancements to the electronic health records of all participating clinical practices, including an asthma severity assessment, clinical decision support, and a patient-tailored asthma action plan. Patients will be followed for 12months and interviewed at baseline, 3, 6, and 12months and data on emergency department visits and hospitalizations will be obtained through the New York State Statewide Planning and Research Cooperative System.

Thromboprophylaxis after hip fracture: evaluation of 3 pharmacologic agents.

We compared the clinical efficacy and side-effect profiles of aspirin, dextran 40, and low-molecular-weight heparin (enoxaparin) in preventing thromboembolic phenomena after hip fracture surgery. All patients admitted with a diagnosis of hip fracture to our institution between July 1, 1987, and December 31, 1999, were evaluated. Study inclusion criteria were age 65 years or older, previously ambulatory, cognitively intact, home-dwelling, and having a nonpathologic intertrochanteric or femoral neck fracture. Each patient received mechanical thromboprophylaxis (above-knee elastic stockings) and 1 pharmacologic agent (aspirin, dextran 40, or enoxaparin); patients who received aspirin were also given a calf sequential compression device. Meeting the selection criteria and included in the study were 917 patients. Findings included low incidence of thromboembolic phenomena (deep vein thrombosis, 0.5%-1.7%; pulmonary embolism, 0%-2.0%; fatal pulmonary embolism, 0%-0.5%) and no difference among the 3 pharmacologic agents in thromboembolic prophylaxis efficacy. Use of enoxaparin was associated with a significant increase (3.8%) in wound hematoma compared with dextran 40 (1.6%) and aspirin (2.4%) (P<.01). The 3 agents were found not to differ with respect to mortality, thromboembolic phenomena, hemorrhagic complications, or wound complications.

Predictive value of preoperative arterial blood gas evaluation for geriatric patients with hip fractures.

The high incidence of preoperative silent pulmonary embolisms (PEs) among elderly patients with hip fractures has led some authors to recommend making acquisition of arterial blood gas (ABG) levels a routine part of the preoperative workup. In the study reported here, we retrospectively reviewed 254 patients in our hip-fracture database and determined that ABG levels have poor positive predictive value for PEs and add little to the positive predictive value or negative predictive value of careful clinical examination. Therefore, we do not recommend making acquisition of ABG levels a routine part of the preoperative evaluation.

Effect of postoperative delirium on outcome after hip fracture.

Nine-hundred twenty-one community-dwelling patients 65 years of age or older, who sustained an operatively treated hip fracture from July 1, 1987 to June 30, 1998 were followed up for the development of postoperative delirium. The outcomes examined in the current study were postoperative complication rates, in-hospital mortality, hospital length of stay, hospital discharge status, 1-year mortality rate, place of residence, recovery of ambulatory ability, and activities of daily living 1 year after surgery. Forty-seven (5.1%) patients were diagnosed with postoperative delirium. Patients who had delirium develop were more likely to be male, have a history of mild dementia, and have had surgery under general anesthesia. Patients who had postoperative delirium develop had a significantly longer length of hospitalization. They also had significantly higher rates of mortality at 1 year, were less likely to recover their prefracture level of ambulation, and were more likely to show a decline in level of independence in basic activities of daily living at the 1-year followup. There was no difference in the rate of postoperative complications, in-hospital mortality, discharge residence, and recovery of instrumental activities of daily living at 1 year.

Time-dependent surgical outcomes following cauda equina syndrome diagnosis: comments on a meta-analysis.

STUDY DESIGN: In this Journal Club review, we critically examine the methodology and results of a recently published meta-analysis describing the time dependency of surgical outcomes associated with cauda equina syndrome (CES) diagnosis. OBJECTIVES: Our objectives are to clarify the strengths, weaknesses, and appropriate use of statistics regarding the findings of the previous publication. SUMMARY OF BACKGROUND DATA: Surgical outcomes from published reports are related to both preoperative conditions and the time between surgery and diagnosis of CES. METHODS: We reexamined many of the papers that were used to create the surgical outcomes data set, including the publications that supplied quantitative information for logistic regression. Of special focus were studies that contributed to the "less than 24 hours from diagnosis" data. The use of statistical parameters such as probabilities and odds ratios to infer possible future outcomes is also addressed to clarify the papers' interpretations. To support the overall limitations of their generalized findings, we conducted a power analysis, which highlights the lack of statistical strength in the resulting conclusions. RESULTS: The results of the initial work state that an advantage exists in treating patients within 48 hours in comparison to treating them during a period greater than 48 hours after the onset of CES symptoms. However, the authors also state that no difference exists between the effects of an early surgery (less than 24 hours) compared with a subsequent period between 24 and 48 hours after CES onset. Key elements of logistic regression and meta-analysis are used to refute specific aspects of their methodology as well as their clinical interpretation regarding acute intervention. CONCLUSIONS: We conclude that a flawed methodology and misinterpretation of results are reported, understating the value of early surgical intervention.

Spatial distribution of hypoxic pulmonary vasoconstriction in the supine pig.

Hypoxic pulmonary vasoconstriction (HPV) serves to maintain optimal gas exchange by decreasing perfusion to hypoxic regions. However, global hypoxia and nonuniform HPV may result in overperfusion of poorly constricted regions leading to local edema seen in high-altitude pulmonary edema. To quantify the spatial distribution of HPV and its response to regional Po2 (Pr(O2)) among small lung regions, five pigs were anesthetized and mechanically ventilated in the supine posture. The animals were ventilated with an inspired O2 fraction (Fi(O2)) of 0.50 and 0.21 and then (in random order) 0.15, 0.12, and 0.09. Regional blood flow (Q) and alveolar ventilation (Va) were measured by using intravenous infusion of 15 microm and inhalation of 1-microm fluorescent microspheres, respectively. Pr(O2) was calculated for each piece at each Fi(O2). Lung pieces differed in their Q response to hypoxia in a manner related to their initial Va/Q with Fi(O2) = 0.21. Reducing Fi(O2) < 0.15 decreased Q to the initially high Va/Q (higher Pr(O2)) regions and forced Q into the low Va/Q (dorsal-caudal) regions. Resistance increased in most lung pieces as Pr(O2) decreased, reaching a maximum resistance when Pr(O2) is between 40 and 50 Torr. Local resistance decreased at PrO2 < 40 Torr. Pieces were statistically clustered with respect to their relative Q response pattern to each Fi(O2). Some clusters were shown to be spatially organized. We conclude that HPV is spatially heterogeneous. The heterogeneity of Q response may be related, in part, to the heterogeneity of baseline Va/Q.