Cost–Effectiveness of Helicopter Transport of Stroke Patients for Thrombolysis

: Objectives: Treatment with intravenous (IV) or intra-arterial (IA) thrombolysis in patients with acute ischemic stroke demands careful patient selection and specialized institutional capabilities. Physicians at hospitals without these resources may prefer patient transfer for acute treatment. Helicopter transport for these patients has been described but without analysis of the effects of its additional cost. The authors examined the cost–effectiveness of helicopter transport for patients with acute stroke. Methods: Costs per additional good outcome and per quality-adjusted life-year (QALY) were calculated using a computer model. Input variables included flight, thrombolytic agent, and angiography costs; annual cost per patient for long-term care of symptomatic stroke; percentage of transported patients treated; percentage of patients receiving IV versus IA therapy; discount rate; absolute probability of good outcome; annual mortality with and without treatment; and quality-of-life modifier. Sensitivity analysis was performed. Results: Helicopter transport of acute stroke patients to tertiary care centers for thrombolytic therapy costs $35,000 per additional good outcome and$3,700 per QALY for the reference case. Cost–effectiveness was sensitive to the effectiveness of thrombolysis but minimally sensitive to most other input values. Cost per QALY ranged from $0 to$50,000, as the absolute increase in good outcomes (minimal or no deficit) ranged from 20% to 5%. Cost–effectiveness was not sensitive to ranges of helicopter flight costs or the proportion of flown patients undergoing treatment. Conclusions: This model indicates helicopter transfer of patients with suspected acute ischemic stroke for potential thrombolysis is cost-effective for a wide range of system variables.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73463/1/S1069-6563_03_00316-6.pd

Thrombolysis for Acute Stroke: The Incontrovertible, the Controvertible, and the Uncertain

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72429/1/j.aem.2004.10.027.pd

ESETT Study Protocol: A multicenter, randomized, blinded, comparative effectiveness study of fosphenytoin, valproic acid, or levetiracetam in the emergency department treatment of patients with benzodiazepine-refractory status epilepticus.

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154124/1/Combined ESETT protocol and SAP with simulation report.pdfDescription of Combined ESETT protocol and SAP with simulation report.pdf : Original protocol, final protocol, original statistical analysis plan, final statistical analysis plan, and design repor

RAMPART (Rapid Anticonvulsant Medication Prior to Arrival Trial): A double‐blind randomized clinical trial of the efficacy of intramuscular midazolam versus intravenous lorazepam in the prehospital treatment of status epilepticus by paramedics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86836/1/j.1528-1167.2011.03235.x.pd

Midazolam Versus Diazepam for the Treatment of Status Epilepticus in Children and Young Adults: A Meta-analysis

Rapid treatment of status epilepticus (SE) is associated with better outcomes. Diazepam and midazolam are commonly used, but the optimal agent and administration route is unclear.The objective was to determine by systematic review if nonintravenous (non-IV) midazolam is as effective as diazepam, by any route, in terminating SE seizures in children and adults. Time to seizure cessation and respiratory complications was examined.We performed a search of PubMed, Web of Knowledge, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, American College of Physicians Journal Club, Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, and International Pharmaceutical Abstracts for studies published January 1, 1950, through July 4, 2009. English language quasi-experimental or randomized controlled trials comparing midazolam and diazepam as first-line treatment for SE, and meeting the Consolidated Standards of Reporting Trials (CONSORT)-based quality measures, were eligible. Two reviewers independently screened studies for inclusion and extracted outcomes data. Administration routes were stratified as non-IV (buccal, intranasal, intramuscular, rectal) or IV. Fixed-effects models generated pooled statistics.Six studies with 774 subjects were included. For seizure cessation, midazolam, by any route, was superior to diazepam, by any route (relative risk [RR] = 1.52; 95% confidence interval [CI] = 1.27 to 1.82). Non-IV midazolam is as effective as IV diazepam (RR = 0.79; 95% CI = 0.19 to 3.36), and buccal midazolam is superior to rectal diazepam in achieving seizure control (RR = 1.54; 95% CI = 1.29 to 1.85). Midazolam was administered faster than diazepam (mean difference = 2.46 minutes; 95% CI = 1.52 to 3.39 minutes) and had similar times between drug administration and seizure cessation. Respiratory complications requiring intervention were similar, regardless of administration route (RR = 1.49; 95% CI = 0.25 to 8.72).Non-IV midazolam, compared to non-IV or IV diazepam, is safe and effective in treating SE. Comparison to lorazepam, evaluation in adults, and prospective confirmation of safety and efficacy is needed.ACADEMIC EMERGENCY MEDICINE 2010; 17:575–582 © 2010 by the Society for Academic Emergency MedicinePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79121/1/j.1553-2712.2010.00751.x.pd

Clinical Practice Variability in Temperature Correction of Arterial Blood Gas Measurements and Outcomes in Hypothermia-Treated Patients After Cardiac Arrest

Mechanical ventilation in patients treated with mild therapeutic hypothermia (MTH) for the postcardiac arrest syndrome may be challenging given changes in solubility of arterial blood gases (ABGs) with cooling. Whether ABG measurements should be temperature corrected (TC) remain unknown. We sought to describe practice variability in TC at a single institution and explored the association between TC and neurological outcome. We conducted a retrospective cohort study reviewing electronic health records of all patients treated with MTH after cardiac arrest. We examined whether the percentage of TC ABGs relative to total number of ABGs drawn for each subject during hypothermia was associated with the neurological outcome at hospital discharge and 6?12-month follow-up. The cerebral performance category of 1?2 was defined as a favorable outcome in the logistic regression models. 1223 ABGs were obtained during MTH on 122 subjects over 6 years. TC was never used in 72 subjects (59%; no TC group), made available in 1?74% of ABGs in 17 subjects (14%; intermediate TC group), and made available in ≥75% of ABGs in 33 subjects (27%; mostly TC group). Groups differed in the proportion of subjects with shockable presenting rhythms (47% vs. 47% vs. 76%, p=0.02) and admitting ICU (p=0.005). Favorable 6-month outcomes were more common in the mostly TC than no TC group (48% vs. 25%; OR [95% CI]: 2.9 [1.2?7.1]), but not after adjustment (OR 1.5, 95% CI 0.33?6.9). There was substantial practice variability in the temperature correction strategy. Availability of temperature-corrected ABGs was not associated with improved neurological outcomes after adjusting for covariates.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140256/1/ther.2014.0029.pd

'Stable' QPOs and Black Hole Properties from Diskoseismology

We compare our calculations of the frequencies of the fundamental g, c, and p--modes of relativistic thin accretion disks with recent observations of high frequency QPOs in X-ray binaries with black hole candidates. These classes of modes encompass all adiabatic perturbations of such disks. The frequencies of these modes depend mainly on only the mass and angular momentum of the black hole; their weak dependence on disk luminosity is also explicitly indicated. Identifying the recently discovered relatively stable QPO pairs with the fundamental g and c modes provides a determination of the mass and angular momentum of the black hole. For GRO J1655-40, M=5.9\pm 1.0 M_\sun, $J=(0.917\pm 0.024)GM^2/c$, in agreement with spectroscopic mass determinations. For GRS 1915+105, M=42.4\pm 7.0 M_\sun, $J=(0.926\pm 0.020)GM^2/c$ or (less favored) M=18.2\pm 3.1 M_\sun, $J=(0.701\pm 0.043)GM^2/c$. We briefly address the issues of the amplitude, frequency width, and energy dependence of these QPOs.Comment: 10 pages, 1 figure. Accepted for publication in Astrophysical Journal Letter

Quality of Emergency Care on the Night Shift

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72839/1/j.aem.2005.09.005.pd

Corotation Resonance and Diskoseismology Modes of Black Hole Accretion Disks

We demonstrate that the corotation resonance affects only some non-axisymmetric g-mode oscillations of thin accretion disks, since it is located within their capture zones. Using a more general (weaker radial WKB approximation) formulation of the governing equations, such g-modes, treated as perfect fluid perturbations, are shown to formally diverge at the position of the corotation resonance. A small amount of viscosity adds a small imaginary part to the eigenfrequency which has been shown to induce a secular instability (mode growth) if it acts hydrodynamically. The g-mode corotation resonance divergence disappears, but the mode magnitude can remain largest at the place of the corotation resonance. For the known g-modes with moderate values of the radial mode number and axial mode number (and any vertical mode number), the corotation resonance lies well outside their trapping region (and inside the innermost stable circular orbit), so the observationally relevant modes are unaffected by the resonance. The axisymmetric g-mode has been seen by Reynolds & Miller in a recent inviscid hydrodynamic accretion disk global numerical simulation. We also point out that the g-mode eigenfrequencies are approximately proportional to m for axial mode numbers |m|>0.Comment: 16 pages, no figures. Submitted to The Astrophysical Journa