Lit Bits: Dec 11, 2010

From the recent medical literature...

1. High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: prospective cohort study

Perry JJ, et al. BMJ 2010; 341:c5204

Objective: To identify high risk clinical characteristics for subarachnoid haemorrhage in neurologically intact patients with headache.

Design: Multicentre prospective cohort study over five years.

Setting: Six university affiliated tertiary care teaching hospitals in Canada. Data collected from November 2000 until November 2005.

Participants: Neurologically intact adults with a non-traumatic headache peaking within an hour.
Main outcome measures: Subarachnoid haemorrhage, as defined by any of subarachnoid haemorrhage on computed tomography of the head, xanthochromia in the cerebrospinal fluid, or red blood cells in the final sample of cerebrospinal fluid with positive results on angiography. Physicians completed data collection forms before investigations.

Results: In the 1999 patients enrolled there were 130 cases of subarachnoid haemorrhage. Mean (range) age was 43.4 (16-93), 1207 (60.4%) were women, and 1546 (78.5%) reported that it was the worst headache of their life. Thirteen of the variables collected on history and three on examination were reliable and associated with subarachnoid haemorrhage. We used recursive partitioning with different combinations of these variables to create three clinical decisions rules. All had 100% (95% confidence interval 97.1% to 100.0%) sensitivity with specificities from 28.4% to 38.8%. Use of any one of these rules would have lowered rates of investigation (computed tomography, lumbar puncture, or both) from the current 82.9% to between 63.7% and 73.5%.

Conclusion: Clinical characteristics can be predictive for subarachnoid haemorrhage. Practical and sensitive clinical decision rules can be used in patients with a headache peaking within an hour. Further study of these proposed decision rules, including prospective validation, could allow clinicians to be more selective and accurate when investigating patients with headache.

Full-text (free): http://www.bmj.com/content/341/bmj.c5204.full

2. Give It Some Time! Plug Pulled Too Soon in Hypothermia-Treated Cardiac-Arrest Patients

American Heart Association (AHA) 2010 Scientific Sessions

Michael O’Riordan. November 14, 2010 (Chicago, Illinois) — New data from multiple studies suggest that clinicians are pulling the plug too early in patients who suffer an out-of-hospital cardiac arrest, especially among patients treated with therapeutic hypothermia. In one study, investigators showed that arbitrarily withdrawing life support 72 hours after an out-of-hospital cardiac arrest prematurely "terminates life" in as much as 10% of patients.

"What is challenging for me, as a clinician who has spent 20 years trying to increase survival rates and to get people alive to the hospital, is to think that we are losing them because we don't know what to do with them," lead investigator Dr Keith Lurie (University of Minnesota, Minneapolis) told heartwire . "It suggests there is a huge opportunity to improve survival. I'm thinking, in absolute terms, of 5% to 10% for any patient who comes into the hospital with a pulse--they have a 5% to 10% greater likelihood of walking out intact if we give them time."

To withdraw support, or the idea of making a pronouncement about the degree of neurologic recovery on day three, needs to be revisited.

In addition to that report, Drs Shaker Eid and Nisha Chandra (John Hopkins University School of Medicine, Baltimore, MD) also provide data suggesting that care for cardiac-arrest patients treated with therapeutic hypothermia is withdrawn too soon. In that analysis, no cardiac-arrest patient who was treated with hypothermia was alert and conscious after 72 hours, whereas one-third of these patients had regained alertness by day seven.

"At this stage, the data are too premature to make any formal recommendations, but we do believe there needs to be a deliberate evaluation of these patients," Chandra told heartwire . "To withdraw support, or the idea of making a pronouncement about the degree of neurologic recovery on day three, needs to be revisited."

A Clinical Disagreement Leads to Study

The results of both investigations were presented this week here at the American Heart Association (AHA) 2010 Resuscitation Science Symposium. In the first trial, Lurie said the small retrospective study emerged from a disagreement about when to withdraw care for a comatose patient who had an out-of-hospital cardiac arrest. Another patient, not alert and unconscious 72 hours following cardiac arrest, was sent to a nursing home, only to wake up two weeks later "feeling fine," but confused about his surroundings.

With the lack of certitude about when to withdraw care and the disagreements that can arise among experienced clinicians, Lurie analyzed the existing data at his center, trying to determine whether clinicians might be giving up on patients too soon and to seek out clinical predictors that might be used to identify patients who wake up late, such as those who awoke 72 hours or more after rewarming from therapeutic hypothermia.

In total, 66 cardiac-arrest patients presented to the hospital between 2007 and 2009 and were cooled to 33ºC for 24 hours. Of these, six patients awoke after 72 hours and had "good neurological function" within 30 days of cardiac arrest. In a multivariate analysis examining predictors of late awakening, those who presented in ventricular fibrillation, those who received bystander-initiated cardiopulmonary resuscitation (CPR) and had witnessed arrests, and those with longer times from the 911 call to advanced life support were more likely to awaken after 72 hours.

To heartwire , Lurie said these late-awakening patients are "slipping through the survival cracks," and the study challenges clinicians by showing them that patients can wake up late, and they need to be more judicious in their recommendations and discussions with family members.

I think we ought to support them and we think we should tell the family there is still a possibility that they'll wake up.

In Minnesota, comatose patients are generally treated after hypothermia for at least 48 hours before any decision to withdraw supportive care. However, once patients are rewarmed to 37ºC, the decision to continue or withdraw support is not standardized and is typically made after consulting with family members. Usually, if a patient is younger, Lurie said he encouraged waiting at least 72 hours before making a decision. Based on this research, his recommendation is to wait at least six or seven days for all patients.

"By day seven, if the patient is still intubated and on a ventilator, that means they're probably not going to do well," said Lurie. "If they're extubated, and breathing on their own, but they just haven't woken up, then I think we ought to support them, and we think we should tell the family there is still a possibility that they'll wake up."

Hypothermia Changes the Game

In an interview with heartwire , Chandra explained that the three-day threshold is a holdover from another era, from a paper published 25 years ago showing that most patients who "wake up" will do so by 72 hours. However, as she and Eid pointed out, treatment following cardiac arrest, particularly the use of therapeutic hypothermia, has changed since then.

In their study, Eid, Chandra, and colleagues wanted to examine the prognosis for recovery in the hypothermia era. They evaluated 47 consecutive patients who survived out-of-hospital cardiac arrest and were admitted to an academic medical center. Of these, 15 patients received therapeutic hypothermia and were cooled to 33ºC, with seven of these individuals surviving until discharge. The remaining patients did not undergo hypothermia, and 13 of these 32 patients survived until discharge.

After 72 hours, 38.5% of patients treated without hypothermia were alert after resuscitation and had mild cognitive defects, as assessed by the cerebral performance category (CPC) score, whereas no cardiac-arrest patient cooled was alert or conscious after three days. By day seven, one-third of the hypothermia patients regained alertness, with mild cognitive deficits, while 83% were recovered by discharge. The average length of hospital stay was 13 days for those undergoing hypothermia compared with four days for those treated without cooling.

"Looking at their neurological recovery, we saw that in those patients who were treated with hypothermia, their recovery was actually delayed," Eid told heartwire . "So you'd have a small number that would have some type of neurologic recovery at day three, but most recover around five to seven days, mostly at seven days."

The use of therapeutic hypothermia for unconscious patients who have been successfully resuscitated from out-of-hospital cardiac arrest has been endorsed by the AHA since 2003. Collectively, said Chandra, the data presented this week are gratifying in that they all show similar results--hypothermia patients take longer to wake up--but are also concerning, because it means clinicians have been pulling the plug too soon. A third study, also presented during the Resuscitation Science Symposium by Dr Kyle McCarty (Maricopa Medical Center, Phoenix, AZ), suggested that care is withdrawn too early in cardiac-arrest patients who underwent therapeutic hypothermia. In that trial, care was withdrawn in 33% of patients within 24 hours and in 30% of patients within 25 hours to 72 hours.

3. PECARN’s Clinical Tool Helps Predict Pediatric Cervical Spine Injury after Blunt Trauma

Leonard JC, Kuppermann N, Olsen C, et al. Ann Emerg Med. 2010 Oct 28. [Epub ahead of print]

Megan Brooks. November 12, 2010 — A group of pediatric emergency care doctors says an eight-factor tool can accurately tell when kids are at high risk for cervical spine injury after blunt trauma.

The presence of any one factor was highly sensitive for cervical spine injury: altered mental status, focal neurologic findings, neck pain, torticollis, substantial torso injury, conditions predisposing to cervical spine injury, diving, and high-risk motor vehicle crash.

The authors of the study point out that according to a multicenter report published in 2001, cervical spine injuries are seen in less than 1% of children who present for trauma evaluation. To play it safe, however, the vast majority of these children are immobilized and imaged for potential cervical spine injury, which can be associated with adverse effects, including pain, pressure wounds, respiratory issues, and exposure to ionizing radiation, often unnecessarily.

In adults, there are validated risk stratification tools to help guide immobilization and imaging decisions; the National Emergency X-Radiography Utilization Study (NEXUS) criteria and the Canadian C-spine Rule are the two most common.

But in children, there is a "pressing need" for a cervical spine injury risk stratification tool, said lead author Dr. Julie C. Leonard of Washington University and St. Louis Children's Hospital in Missouri and colleagues in the November 1 online issue of Annals of Emergency Medicine.

To that end, the researchers compared 1060 randomly selected children without cervical spine injury to 540 blunt trauma patients younger than age 16 who had cervical spine x-rays done at one of 17 US hospitals in the Pediatric Emergency Care Applied Research Network. The eight-factor tool is drawn from the results of multivariate analyses of the data from these children.

"These historical and physical examination findings are highly predictive of cervical spine injury in children after trauma," the authors note in their report. Having one or more of these factors was 98% sensitive and 26% specific for cervical spine injury.

The predictive value of the eight-factor model was confirmed in additional analyses using two different control groups (i.e., a group matched to cases according to age and mechanism of injury and, for cases receiving out-of-hospital EMS care, a group of patients matched on age who had also received pre-hospital EMS care).

In an e-mail to Reuters Health, Dr. Leonard noted that the factors associated with cervical spine injury in children differ somewhat from the factors contained in the NEXUS tool and Canadian C-spine Rule -- which isn't that surprising.

"When compared to adults, children have age-dependent anatomic differences and differing injury patterns," she said. They also have differing injury mechanisms and age-related differences in ability to localize and communicate pain.

"As a result, the constellation of predictors for cervical spine injury in children differed from the two tools that have been validated for use in adults (the NEXUS tool and the Canadian C-spine Rule). Interestingly, most of the predictors identified in our model are included in one or the other of these decision support tools," she added.

"While the findings from our study are compelling, the tool should be prospectively tested in the out-of-hospital setting before it is accepted as a standard of care for injured children," Dr. Leonard told Reuters Health. It requires "prospective refinement and validation."

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21035905

4. Postdischarge secobarbital after ED migraine treatment decreases pain and improves resolution

Gerhardt RT, et al. Amer J Emerg Med. 2011;29:86-90.

Objective
The objective of the study was to determine whether the addition of postdischarge oral secobarbital to standard emergency department (ED) migraine headache therapy improves pain relief and headache resolution compared with placebo.

Setting
The setting is an urban ED with 70 000 yearly visits.

Methods
This is an Institutional Review Board–approved, randomized, nonconsecutive, double-blinded, concealed, and placebo-controlled clinical trial. Patients with a clinical diagnosis of migraine underwent standard ED treatment and were discharged with 2 tablets of either secobarbital 100 mg or placebo. At home arrival, subjects recorded headache pain on a visual analog scale (VAS), took 1 tablet, and went to bed, taking the second tablet after 1 hour if not asleep. Upon awakening, subjects completed a second VAS and survey.

Statistical analysis
The VAS data were analyzed using 2-tailed t test with unequal variance. Headache resolution data were analyzed using Fisher exact test.

Results
Fifty subjects were enrolled. Complete data and follow-up were available for 30 subjects (60%). Fourteen subjects received placebo; 16 received secobarbital. Secobarbital subjects reported an average headache pain decrease of 25 mm (−13 to −38) compared with an average increase of 3 mm (−13 to 19) in the placebo group (P = .01). Ninety-four percent of the secobarbital group vs 50% of the placebo group had complete or partial headache resolution (P less than .02). All subjects in the secobarbital group reported some relief.

Conclusions
Addition of postdischarge oral secobarbital to a standard ED migraine treatment regimen decreased headache pain at 24 hours after discharge and improved the rate of headache resolution compared with placebo.

5. My Mother Was Right About VapoRub!

Paul IM, et al. Vapor rub, petrolatum, and no treatment for children with nocturnal cough and cold symptoms. Pediatrics. 2010;126:1092-9.

OBJECTIVE: To determine if a single application of a vapor rub (VR) or petrolatum is superior to no treatment for nocturnal cough, congestion, and sleep difficulty caused by upper respiratory tract infection.

METHODS: Surveys were administered to parents on 2 consecutive days-on the day of presentation when no medication had been given the previous evening, and the next day when VR ointment, petrolatum ointment, or no treatment had been applied to their child's chest and neck before bedtime according to a partially double-blinded randomization scheme.

RESULTS: There were 138 children aged 2 to 11 years who completed the trial. Within each study group, symptoms were improved on the second night. Between treatment groups, significant differences in improvement were detected for outcomes related to cough, congestion, and sleep difficulty; VR consistently scored the best, and no treatment scored the worst. Pairwise comparisons demonstrated the superiority of VR over no treatment for all outcomes except rhinorrhea and over petrolatum for cough severity, child and parent sleep difficulty, and combined symptom score. Petrolatum was not significantly better than no treatment for any outcome. Irritant adverse effects were more common among VR-treated participants.

CONCLUSIONS: In a comparison of VR, petrolatum, and no treatment, parents rated VR most favorably for symptomatic relief of their child's nocturnal cough, congestion, and sleep difficulty caused by upper respiratory tract infection. Despite mild irritant adverse effects, VR provided symptomatic relief for children and allowed them and their parents to have a more restful night than those in the other study groups.

6. A Clinical Prediction Model to Estimate Risk for 30-Day Adverse Events in Emergency Department Patients with Symptomatic Atrial Fibrillation

Barrett TW, et al. Ann Emerg Med. In press.

Study objective
Atrial fibrillation affects more than 2 million people in the United States and accounts for nearly 1% of emergency department (ED) visits. Physicians have little information to guide risk stratification of patients with symptomatic atrial fibrillation and admit more than 65%. Our aim is to assess whether data available in the ED management of symptomatic atrial fibrillation can estimate a patient's risk of experiencing a 30-day adverse event.

Methods
We systematically reviewed the electronic medical records of all ED patients presenting with symptomatic atrial fibrillation between August 2005 and July 2008. Predefined adverse outcomes included 30-day ED return visit, unscheduled hospitalization, cardiovascular complication, or death. We performed multivariable logistic regression to identify predictors of 30-day adverse events. The model was validated with 300 bootstrap replications.

Results
During the 3-year study period, 914 patients accounted for 1,228 ED visits. Eighty patients were excluded for non–atrial-fibrillation-related complaints and 2 patients had no follow-up recorded. Of 832 eligible patients, 216 (25.9%) experienced at least 1 of the 30-day adverse events. Increasing age (odds ratio [OR] 1.20 per decade; 95% confidence interval [CI] 1.06 to 1.36 per decade), complaint of dyspnea (OR 1.57; 95% CI 1.12 to 2.20), smokers (OR 2.35; 95% CI 1.47 to 3.76), inadequate ventricular rate control (OR 1.58; 95% CI 1.13 to 2.21), and patients receiving β-blockers (OR 1.44; 95% CI 1.02 to 2.04) were independently associated with higher risk for adverse events. C-index was 0.67.

Conclusion
In ED patients with symptomatic atrial fibrillation, increased age, inadequate ED ventricular rate control, dyspnea, smoking, and β-blocker treatment were associated with an increased risk of a 30-day adverse event.

7. Use of CT Scans in Emergency Departments 'Skyrocketing'

Larson DB, et al. Radiology. 2010 Nov 30. [Epub ahead of print]

National Trends in CT Use in the Emergency Department: 1995-2007.

Fran Lowry. December 9, 2010 (Chicago, Illinois) — The use of computed tomography (CT) scans in emergency departments (EDs) throughout the United States has increased dramatically in recent years, and this increase shows little signs of slowing, according to a study presented here at the Radiological Society of North America 96th Scientific Assembly and Annual Meeting, and published online November 30 in Radiology.

From 1995 to 2007, the number of visits in which a CT scan was performed increased 6-fold, from 2.7 million to 16.2 million, representing a growth rate of 16% per year, said David B. Larson, MD, MBA, from Cincinnati Children's Hospital Medical Center in Ohio.

"This increase is potentially concerning, given the questions about the safety of radiation exposure and increasing healthcare costs," he told Medscape Medical News.

The percentage of visits that were associated with a CT scan also increased substantially, from 2.8% of all visits in 1995 to 13.9% of all visits in 2007, Dr. Larson said.

He and his team examined data from the Centers for Disease Control and Prevention's National Hospital Ambulatory Medical Care Survey, which collects data on approximately 30,000 emergency visits each year.

CT use was greater in older patients, white patients, patients admitted to the hospital, and in hospitals located in urban areas. Toward the end of the study period, most CTs were for abdominal pain, headache, and chest pain.

According to Dr. Larson, it is not just the magnitude of the growth in CT scanning that is so striking, but the nature of that growth. "When you look at the model of how technology diffuses in a population, it usually starts with accelerating growth and then, after a period of time, it begins to decelerate and taper off. But the use of CT scans is still in the acceleration phase, at least in 2007. It hasn't even started to taper by this time period, so we've seen very rapid, steady, and sustained growth."

He added that there is no question that in the setting of a life-threatening injury or severe illness, a CT is appropriate. "The real question is when an indication is less clear, where there is less severe illness. At what point do you draw the line and say no to CT? It is such a great test, it is an excellent modality, and in some ways it's harder to make the decision not to do it."

Increase in CT Scans Might Not Be a Bad Thing

Elliot K. Fishman, MD, professor of radiology, surgery, and oncology at Johns Hopkins Hospital in Baltimore, Maryland, believes it is important to put this increase in the proper perspective.

"When you first look at this study, there is a tendency to say: 'Oh dear, we've got increased volume. This must be terrible.' But I think for a lot of the volume increases there are very good reasons," he told Medscape Medical News.

"If you look at those years, it was an era when CT was really moving into the [emergency department]. People were finally getting scanners in the [emergency department]. Before that, the scanner was in the hospital, and this made it difficult to schedule an exam. So the ability to get a scan when you needed it in the emergency setting became much more common."

This period was also one of rapid growth in terms of CT technology, Dr. Fishman noted. "We went from basically 4 slice, to 16, to 64. So it wasn't like the technology stood still."

CT also came to be used in place of other tests for ruling out common reasons for visits to the emergency department, such as pulmonary embolism and appendicitis.

"It became very common in the [emergency] setting to use CT to rule out pulmonary embolism. Before the advent of CT, this was done by nuclear medicine," Dr. Fishman noted. "This study does not address whether CT replaced anything, but it is very probable that some of the CT scans are replacing other tests; they didn't just fall out of the sky and start being used for no reason," he said.

Abdominal pain is a common complaint in emergency departments, and CT scans can rule out appendicitis. "These days, the percentage of people who go to surgery with a negative appendix is well under 5%, whereas it used to be 20% to 30%. Stone disease is another common cause of abdominal pain, and CT can rule that out. This is another of the true growth areas in CT, and here it was probably replacing plain films and [intravenous pyelograms]."

Another area of true growth for CT is in triage.

"CTs in the [emergency] setting are really good triage tools," said Dr. Fishman. "We used to keep people in the [emergency department] for 12 to 24 hours to observe them, but with CT, if you suspect something, you go in and scan the patient and if there is nothing there, you discharge the patient. So CT, because of its high positive and negative predictive value, makes it easy to do rapid triage. In this cost-conscious era, it is very cost effective."

Dr. Fishman said he is not surprised to learn that growth of CT was so rapid from 1995 to 2007. But he believes that now, such growth has plateaued. "From 2007 to 2010, I would say, those curves have flattened. Here at Hopkins, our volumes are probably down about 7% to 10%."

Dr. Larson and Dr. Fishman have disclosed no relevant financial relationships.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21115875

8. Oxygen saturation is not clinically useful in the exclusion of bacterial pneumonia in febrile infants

Simon LV, et al. Emerg Med J 2010;27:904-906.

Background: Acute respiratory infection remains a common presentation to Emergency Departments. Oxygen saturations (Sao2) may be useful in determining which febrile infants require chest x-rays (CXR) in investigation for bacterial pneumonia (PNA). This study aimed to determine whether Sao2 is clinically useful in excluding bacterial PNA in febrile infants less than 24 months.

Methods: A febrile infant registry was instituted at a tertiary care military hospital (55 000 annual patients, 27% children) from December 2002–December 2003. Eligible patients consisted of infants younger than 3 months with temperature 38°C and up or 3–24 months with temperature 39°C or more. Bacterial PNA was defined in this cohort by a CXR revealing a ‘lobar infiltrate’ by a board-certified radiologist. Descriptive statistics are presented on groups who received CXR versus groups who did not, and on infants who had bacterial PNA versus those who did not. Student t tests were used to compare maximum temperature (Tmax), RR, and Sao2. Logistic regression for PNA was performed using age, sex, Tmax, RR, HR and Sao2. A Receiver Operator Characteristic (ROC) curve was created to show Sao2 cut-off points as related to sensitivity and specificity.

Results: 985 patients (55% boys; median age: 12 months) met entry criteria. 790 underwent CXR and 82 were diagnosed with bacterial PNA. Sao2 was lower in infants with bacterial PNA (96.6%±2.5% vs 97.7%±1.8%, p less than 0.001). Sao2 was also predictive of bacterial PNA by logistic regression (p=0.017) but the ROC curve yielded a poor sensitivity/specificity profile (area under curve (AUC) of 0.6786).

Conclusions: In febrile infants, Sao2 was not found to be clinically useful for excluding bacterial PNA.

9. Meta-analysis: Effect of B-Type Natriuretic Peptide Testing on Clinical Outcomes in Patients with Acute Dyspnea in the Emergency Setting

Lam LL, et al. Ann Intern Med. 2010;153:728-735.

Background: Although the accuracy of B-type natriuretic peptide (BNP) testing for diagnosing acute decompensated heart failure has been extensively evaluated, the effect of this test on clinical outcomes remains unclear.

Purpose: To investigate whether BNP testing of patients presenting with acute dyspnea in the emergency department leads to fewer admissions, shorter length of stay, and improved short-term survival compared with usual care without BNP testing.

Data Sources: Two reviewers searched Ovid MEDLINE and EMBASE, without language restrictions, to identify pertinent studies published from January 1996 to July 2010.

Study Selection: Randomized, controlled trials that compared BNP testing to diagnose heart failure with routine care in patients presenting with acute dyspnea and information about 1 or more of the following outcomes: mortality, admission, or length of hospital stay.

Data Extraction: Two authors independently reviewed articles, extracted data, and assessed quality and risk for bias of studies.

Data Synthesis: Five trials conducted in 5 countries and involving 2513 patients met inclusion criteria. Study settings had differing emergency department staffing models and used various BNP testing protocols. The pooled estimate of effect of BNP testing on all-cause mortality had wide confidence bounds and was inconclusive (odds ratio, 0.96 [95% CI, 0.65 to 1.41]). Admission rates decreased in the tested group compared with the control group (odds ratio, 0.82 [CI, 0.67 to 1.01]), although this finding was not statistically significant. Length of hospital and critical care unit stay were both modestly reduced in the tested group compared with the control group, with a mean difference of −1.22 days (CI, −2.31 to −0.14 day) and −0.56 day (CI, −1.06 to −0.05 day), respectively.

Limitation: Few relevant trials were studied. Patients included in the trials and the settings in which trials were conducted were heterogeneous.

Conclusion: B-type natriuretic peptide testing in the emergency department for patients presenting with acute dyspnea decreased length hospital of stay by about 1 day and possibly reduced admission rates but did not conclusively affect hospital mortality rates.

10. A Randomised Placebo Controlled Trial of Adrenaline in Cardiac Arrest - the PACA Trial

Jacobs I, et al. Resuscitation Science Symposium. Best of the Best Oral Abstract Presentations

Background: Adrenaline (Epinephrine) remains the primary pharmacological agent in cardiac arrest. Despite a total absence of any experimental trials to establish efficacy, adrenaline is considered standard of care in resuscitation.

Methods: We undertook a double-blind randomised placebo controlled trial of adrenaline in out-of-hospital cardiac arrest in Perth, Western Australia between August 2006 and November 2009. Patients were randomly assigned to receive either 1 ml aliquots of adrenaline 1:1000 or Sodium Chloride (0.9%) by means of computerised random number generator. Primary outcome was survival to hospital discharge and secondary outcomes included return of spontaneous circulation (ROSC) and neurological outcome (Cerebral Performance Category Score) at hospital discharge. Odds ratios (OR) and 95% confidence intervals were derived for these outcomes and analysis was on an intention to treat basis.

Results: During the study period paramedics attended 4107 cardiac arrests of which resuscitation was commenced in 1586 (38.6%) patients. Of these 602 (37.9%) were enrolled into the study with a further 67 (11.1%) being excluded after randomisation. Of the remaining 535 patients 262 (48.9%) and 273 (51.0%) received placebo or adrenaline respectively. The percentage male (70.6% versus 74.8%); mean age (64.8 versus 65.4 years) and percentage of patients who received bystander CPR (55.7% versus 53.1%) were similar for the adrenaline and placebo groups respectively. ROSC was achieved in 83 (30.4%) patients receiving adrenaline and 29 (11.1%) receiving placebo - OR= 3.51 [95% CI 2.21 to 5.58]. Survival to hospital discharge occurred in 11 (4.1%) and 5 (1.9%) of the adrenaline and placebo patients respectively - OR= 2.16 [95% CI: 0.74 to 6.30]

Conclusions: The use of adrenaline in cardiac arrest was associated with a significant increase in the proportion of patients achieving ROSC however this improvement did not extend to survival to hospital discharge. As our results are unable to rule out a clinically meaningful benefit of adrenaline in terms of survival to hospital discharge, further investigation into the post resuscitation period for those achieving ROSC is required in order to identify management strategies to improve survival.

11. Emergency Physician Ultrasonography for Evaluating Patients at Risk for Ectopic Pregnancy: A Meta-Analysis

Stein JC, et al. Ann Emerg Med. 2010;56:674-683.

Study objective
Ectopic pregnancy is a common concern in emergency departments (EDs) and remains the leading cause of first-trimester mortality. Pelvic ultrasonography by emergency physicians has been investigated as a diagnostic test for ectopic pregnancy. We present a meta-analysis of the use of emergency physician ultrasonography in the evaluation of patients at risk of ectopic pregnancy.

Methods
A structured search was performed of both MEDLINE and EMBASE. Inclusion criteria were that (1) the study reported original research on ED patients at risk for ectopic pregnancy; (2) an emergency physician performed and interpreted the initial pelvic ultrasonography; and (3) follow-up was conducted on all patients. Sensitivity was defined as the proportion of patients with ectopic pregnancy for which ED ultrasonography demonstrated no intrauterine pregnancy. A random-effects model was used to obtain summary test characteristics.

Results
The initial search showed 576 publications, abstract review yielded 60 with potential relevance, and 10 studies were included. There was a total of 2,057 patients, of whom 152 (7.5%) had ectopic pregnancy. The pooled sensitivity estimate was 99.3% (95% confidence interval [CI] 96.6% to 100%), negative predictive value was 99.96% (95% CI 99.6% to 100%), and negative likelihood ratio was 0.08 (95% CI 0.025 to 0.25), all without significant heterogeneity.

Conclusion
The results of this meta-analysis suggest that in a wide variety of clinical settings, the use of bedside ultrasonography performed by emergency physicians as a diagnostic test for ectopic pregnancy provides excellent sensitivity and negative predictive value. Visualization of an intrauterine pregnancy by an emergency physician is generally sufficient to rule out ectopic pregnancy.

Full-text (free): http://www.annemergmed.com/article/S0196-0644(10)01196-0/fulltext

12. Prehospital Intubation Results in Worse Outcomes in Adult Cardiac Arrest Patients

Prehospital intubation was negatively associated with return of spontaneous circulation and survival to discharge.

Although studies in children suggest worse outcomes among those managed with prehospital intubation versus bag-valve-mask ventilation (JW Emerg Med Apr 1 2000), few studies have addressed this issue in adult patients with out-of-hospital cardiac arrest. In a retrospective study of data from an emergency medical services system in North Carolina for 1142 adult patients with cardiac arrest, researchers assessed the association between performance of prehospital endotracheal intubation and return of spontaneous circulation (ROSC) in the field and survival to discharge. The decision to attempt intubation was at the paramedics' discretion.

Intubation was not performed in 203 patients. In analysis that controlled for initial arrest rhythm, patients who were managed without any attempt at prehospital intubation were 2.3 times more likely to have ROSC in the field and 5.5 times more likely to be discharged from the hospital alive than patients who had one successful prehospital intubation attempt.

Comment: The 2010 American College of Cardiology/American Heart Association Advanced Cardiac Life Support guidelines emphasize chest compressions before airway management for all patients with cardiac arrest except newborns. Although these retrospective results could not determine cause and effect, the findings suggest that attempts at prehospital intubation are associated with worse outcomes in patients with out-of-hospital cardiac arrest. Interruption of chest compressions might contribute to the worse outcomes. Further study is warranted to determine whether prehospital intubation might cause more harm than good in adult patients with cardiac arrest.

— Diane M. Birnbaumer, MD, FACEP. Published in Journal Watch Emergency Medicine November 19, 2010. Citation: Studnek JR et al. The association between prehospital endotracheal intubation attempts and survival to hospital discharge among out-of-hospital cardiac arrest patients. Acad Emerg Med 2010; 17:918.

13. 'Hands-Only' CPR Works, but Survival Still Low

Kitamura T, et al. Time-dependent effectiveness of chest compression-only and conventional cardiopulmonary resuscitation for out-of-hospital cardiac arrest of cardiac origin. Resuscitation. 2010 Nov 18. [Epub ahead of print]

Amy Norton. NEW YORK (Reuters Health) Nov 30 - "Hands-only" cardiopulmonary resuscitation (CPR) is usually as effective as traditional CPR that includes mouth-to-mouth breathing - but the odds that cardiac arrest victims will survive with minimal brain damage are still quite low, a large study from Japan finds.

Researchers say the findings support statements from the American Heart Association and other groups that compression-only CPR can be a comparable alternative to the traditional technique of alternating chest compressions with mouth-to-mouth breathing.

Since 2008, the American Heart Association has recommended that when an adult suddenly collapses and isn't breathing, bystanders should perform hands-only CPR -- strong, steady chest compressions, at a rate of 100 per minute -- unless they are confident in their ability to perform conventional CPR.

The reasoning is that hands-only CPR is easier for a layperson to learn and remember, and that people are more likely to administer CPR to a stranger if mouth-to-mouth contact is not required.

Moreover, studies in recent years have shown that hands-only CPR can be as effective as the traditional version for when arrest has a cardiac etiology.

But these latest results, published online November 22nd in Resuscitation, also underscore the fact that regardless of CPR technique, the chances of surviving cardiac arrest, with or without significant brain damage, are still low.

Using national data on more than 55,000 Japanese adults who suffered a witnessed cardiac arrest, the researchers found that roughly 7% of those who received CPR from a bystander and were treated by paramedics within 15 minutes survived with a favorable neurological outcome.

There was no significant difference between those who received conventional CPR and those who received the hands-only approach: 7.1% and 6.4%, respectively, survived and had a favorable neurological outcome one month later -- meaning no greater than "moderate" brain damage that left them still able to perform routine daily activities.

That compared with a rate of 3.8% among victims who received no bystander CPR and were treated by emergency medical services within 15 minutes of their collapse.

When treatment from paramedics was delayed for more than 15 minutes, survival with minimal brain damage was universally lower -- though somewhat higher with conventional CPR relative to hands-only and no CPR. Among victims who received no CPR, just 0.7% survived with no more than moderate brain damage one month later. That figure was 1.3% among those who received hands-only CPR, and 2% among victims who received conventional CPR.

Despite that small advantage, though, the findings still support the recommendation for most bystanders to perform hands-only CPR, according to the researchers, led by Dr. Tetsuhisa Kitamura of Kyoto University Health Service.

Dr. Michael Sayre, chair of the American Heart Association's Emergency Cardiovascular Care Committee, agreed. In an interview, he noted that in most cases, paramedics will reach cardiac-arrest victims within 15 minutes.

But he said that the current findings underscore the importance of prompt action -- of bystanders not only starting CPR, but also immediately calling 911. It's estimated that for every minute defibrillation is delayed, the odds of survival drop by 10%.

And while survival rates were low in this study, regardless of CPR technique, Dr. Sayre said that the "good news" is in the changes seen over time.

The 55,014 cardiac arrests in the study occurred between 2005 and 2007; it was in 2005 that the hands-only technique was first promoted as an "acceptable" way to perform CPR. And over that time, the proportion of cardiac-arrest victims who received CPR of any kind increased.

In the last few months of 2007, 28.5% received hands-only CPR -- up from 17% in the first few months of 2005. That was countered by only a small dip in conventional CPR -- from just under 20% in early 2005 to 17% in late-2007.

Moreover, overall survival with a good neurological outcome improved over time. In the last few months of 2007, those survival rates were 7% with hands-only and 6% with conventional CPR, compared with 3% and 4%, respectively, in early 2005.

"The good news is that it's getting better over time," Dr. Sayre said. And he predicted that if a greater proportion of cardiac-arrest victims got prompt CPR and emergency medical attention, more lives could be saved.

A study published last month in the Journal of the American Medical Association found that a mass campaign in Arizona to promote hands-only CPR may be paying off. Five years after the state began the effort, the percent of cardiac-arrest victims surviving to hospital discharge had more than doubled -- from less than 4% in 2005 to just under 10% in 2009.

At the same time, the rate of CPR increased from about 28% to 40%, with a steep increase in compression-only CPR and a drop in CPR with rescue breathing.

While other factors, including changes in medical care, may have been partially at work, the researchers tied hands-only CPR to a 60% increase in the odds of surviving cardiac arrest, versus both no CPR and conventional CPR.

"Performing hands-only CPR can be life-saving," Dr. Sayre said, "and people should not hesitate to help."

The American Heart Association has a Web site with information on how to effectively perform hands-only CPR, at http://handsonlycpr.org/

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21093974

14. Point-of-care testing for coagulation studies in a stroke protocol: a time-saving innovation

Drescher MJ, et al. Amer J Emerg Med 2011;29:82-85.

Study Objectives
Time counts in thrombolytic therapy for stroke. An international normalized ratio (INR) greater than 1.7 may preclude its use. We studied whether the use of point-of-care testing (POCT) for INR in the emergency department (ED) may substitute for the same test done in the central hospital laboratory, thereby reducing time to treatment.

Methods
We performed a prospective observational study comparing a POCT analysis of INR (i-STAT-1; Abbott Inc, Abbott Park, Ill) with a simultaneously drawn sample sent to the central laboratory. We tested a convenience sample of adult patients taking warfarin who presented to the ED of a tertiary teaching hospital.

Results
Thirty-two patients were enrolled. A receiver operator curve analysis was performed. Sensitivity and specificity were calculated for laboratory INR cutoff of 1.7. The area under the curve was 0.979 (95% confidence interval [CI], 0.843-0.991). When POCT INR was 2.1, the sensitivity for laboratory INR being higher than 1.7 was 100% (CI, 62.9%-100.0%), and the specificity was 90.5 (CI, 69.6-98.5). When POCT INR was 1.8, the specificity for laboratory INR being lower than 1.7 was 100% (CI, 83.7%-100%), and the sensitivity was 62.5% (CI, 24.7%-91.0%). The regression coefficient (r) value was 0.9648.

Conclusion
Correlation of POCT INR with that of the central laboratory and receiver operator curve characteristics are excellent. In general, POCT INR is about 0.3 higher than the laboratory INR. This is not generally of clinical importance, but when using cutoff of 1.7 (central laboratory), it may be. We describe a 3-tiered system for use of POCT INR in determining use of tissue-type plasminogen activator.

15. Blunt Advice: Don't Use Recombinant Factor VIIa for Non-Hemophiliac Bleeding

NEW YORK (Reuters Health) Nov 15 - The off-label use of recombinant factor VIIa for hemostasis in patients without hemophilia confers only modest benefits but may increase the risk of thromboembolic events, according to results of a meta-analysis published online November 15 in the Canadian Medical Association Journal.

"Our systematic review did not show a consistent benefit of off-label use of recombinant factor VIIa in the therapeutic setting and at best only modest benefits in the prophylactic setting," the authors conclude. "Given its potential risks, off-label use of this hemostatic agent cannot be recommended, and in most instances, it should be restricted to clinical trials."

In their introduction, Dr. Yulia Lin at the Sunnybrook Health Sciences Centre in Toronto, Ontario, Canada, and colleagues in the UK note that many physicians apparently believe off-label use of recombinant factor VIIa is safe and effective. For example, one registry recorded that only 1% of 2700 patients treated with recombinant factor VIIa had hemophilia.

To assess outcomes in patients without hemophilia, the team identified 14 trials involving a total of 1137 patients in which recombinant factor VIIa was used prophylactically and 12 trials that included 2538 patients where it was used therapeutically.

With prophylactic use, the pooled data gave a relative mortality risk of 0.88, which wasn't significant. The reduction in blood loss with use of recombinant factor VIIa was modest at 276 mL, and that's "likely to be an overestimate," the researchers report.

Results were similar and not statistically significant with therapeutic use: the relative mortality risk was 0.90 and the RR for bleeding was 1.05.

As for thromboembolic events, there was a trend toward increased risk with both types of usage: with prophylactic use the RR was 1.38 and with therapeutic use it was 1.18.

"Continued lack of clarity about the overall clinical effectiveness certainly stems from recombinant factor VIIa being genuinely less effective than was originally predicted," Dr. Lin and colleagues state.

They conclude, "Clinically significant benefits of recombinant factor VIIa as a general hemostatic agent in patients without hemophilia remain unproven."

CMAJ Abstract: http://www.cmaj.ca/cgi/content/abstract/cmaj.100408v1

16. Compression Ultrasonography of the Lower Extremity with Portable Vascular Ultrasonography Can Accurately Detect DVT in the ED

Crisp JG, et al. Ann Emerg Med. 2010;56:601-610.

Study objective
Compression ultrasonography of the lower extremity is an established method of detecting proximal lower extremity deep venous thrombosis when performed by a certified operator in a vascular laboratory. Our objective is to determine the sensitivity and specificity of bedside 2-point compression ultrasonography performed in the emergency department (ED) with portable vascular ultrasonography for the detection of proximal lower extremity deep venous thrombosis. We did this by directly comparing emergency physician–performed ultrasonography to lower extremity duplex ultrasonography performed by the Department of Radiology.

Methods
This was a prospective, cross-sectional study and diagnostic test assessment of a convenience sample of ED patients with a suspected lower extremity deep venous thrombosis, conducted at a single-center, urban, academic ED. All physicians had a 10-minute training session before enrolling patients. ED compression ultrasonography occurred before Department of Radiology ultrasonography and involved identification of 2 specific points: the common femoral and popliteal vessels, with subsequent compression of the common femoral and popliteal veins. The study result was considered positive for proximal lower extremity deep venous thrombosis if either vein was incompressible or a thrombus was visualized. Sensitivity and specificity were calculated with the final radiologist interpretation of the Department of Radiology ultrasonography as the criterion standard.

Results
A total of 47 physicians performed 199 2-point compression ultrasonographic examinations in the ED. Median number of examinations per physician was 2 (range 1 to 29 examinations; interquartile range 1 to 5 examinations). There were 45 proximal lower extremity deep venous thromboses observed on Department of Radiology evaluation, all correctly identified by ED 2-point compression ultrasonography. The 153 patients without proximal lower extremity deep venous thrombosis all had a negative ED compression ultrasonographic result. One patient with a negative Department of Radiology ultrasonographic result was found to have decreased compression of the popliteal vein on ED compression ultrasonography, giving a single false-positive result, yet repeated ultrasonography by the Department of Radiology 1 week later showed a popliteal deep venous thrombosis. The sensitivity and specificity of ED 2-point compression ultrasonography for deep venous thrombosis were 100% (95% confidence interval 92% to 100%) and 99% (95% confidence interval 96% to 100%), respectively.

Conclusion
Emergency physician–performed 2-point compression ultrasonography of the lower extremity with a portable vascular ultrasonographic machine, conducted in the ED by this physician group and in this patient sample, accurately identified the presence and absence of proximal lower extremity deep venous thrombosis.

17. Closed Reduction of Distal Forearm Fractures by Pediatric Emergency Physicians

Khan S, et al. Acad Emerg Med. 2010;1169–1174.

Objectives:  The objective of this study was to determine if there exist differences in length of stay (LOS) in the emergency department (ED) and need for reintervention to restore alignment after distal forearm fracture reduction by pediatric emergency physicians (EPs) versus postgraduate year 3 or 4 orthopedic residents.

Methods:  In a prospective trial at a busy urban pediatric ED, children with closed distal forearm fractures that met predefined criteria for manipulation were randomized to treatment by a postgraduate year 3 or 4 orthopedic resident or by a pediatric EP who had received focused training in forearm fracture reduction. Prereduction, postreduction, and follow-up radiographs were evaluated by an attending pediatric orthopedic surgeon who was unaware of the assigned group. The following outcomes were assessed: LOS during the initial ED encounter, adequacy of alignment immediately postreduction and at follow-up visits after discharge from the ED, the need for remanipulation, unscheduled ED visits, and radiographic healing at 6–8 weeks after injury.

Results:  A total of 103 children were randomized into the pediatric EP (52 patients, mean age 9.1 years) and orthopedic resident (51 patients, mean age 9.7 years) groups. Patients in the two groups were similar in age, involvement of the physes, degree of angulation, percentage of displacement, and need for procedural sedation. The mean LOS in the ED was 4.5 hours in the pediatric EP group versus 5.0 hours in the orthopedic resident group (difference in means –0.5 hours, 95% confidence interval [CI] = −1.26 to 0.37 hours). Remanipulation was required in 4 of 48 (8.3%) in the pediatric EP group versus 6 of 48 (12.5%) in the orthopedic resident group (odds ratio [OR] = 0.64; 95% CI = 0.16 to 2.67). Unscheduled ED visits for cast-related problems occurred in 6 of 51 (11.8%) in the pediatric EP group and 4 of 52 (7.7%) in the orthopedic resident group (OR = 1.59; 95% CI = 0.38 to 6.39). None of these patients with unscheduled ED visits developed compartment syndrome or required admission.

Conclusions:  Length of stay in the ED and clinical outcomes after closed reduction of forearm fractures by trained pediatric EPs are comparable to those after closed reduction by orthopedic residents.

18. Study: Many ED Visits Could Be Handled by Urgent, Retail Clinics

CaliforniaHealthline

Between 13.7% and 27.1% of patients who visit emergency departments could have obtained care from a retail clinic or urgent care clinic instead, a move that could reduce U.S. health care spending by up to $4.4 billion annually, according to a study published Tuesday in the journal Health Affairs, HealthLeaders Media reports (Clark, HealthLeaders Media, 9/8).

Researchers from the RAND Corporation conducted the study, which received funding from the California HealthCare Foundation. CHCF publishes California Healthline ("KPCC News," KPCC, 9/7).

Study Details

For the study, researchers analyzed 354 million annual acute care visits in EDs, retail clinics and urgent care centers between 2001 and 2004 (HealthLeaders Media, 9/8).

They found that retail clinics and urgent care centers effectively could handle conditions such as:
• Lacerations;
• Minor fractures;
• Minor infections; and
• Strains.

Researchers estimated that:
• 13.7% of all hospital ED visits could be treated at a retail clinic;
• 13.4% of ED visits could be treated at an urgent care center; and
• A total of 27.1% of ED visits could be handled by either type of facility.

However, they noted that only 16.8% of all ED visits likely could be redirected to retail and urgent care clinics because of their operating hours (HealthDay/U.S. News & World Report, 9/7).

Researchers also noted that retail and urgent care clinics could help ameliorate the country's growing shortage of primary care physicians. They predicted that the shortage likely will become worse as the U.S. population ages, which could lead more people to seek care in EDs.

Disagreement with Recommendations

Angela Gardner, president of the American College of Emergency Physicians, said her organization has concerns about the RAND researchers' recommendations to shift more care to retail and urgent care clinics.

Gardner said retail clinics vary in quality and might not be properly equipped to manage a serious condition. She added that some people visit EDs for seemingly minor problems that turn out to be serious ailments.

In addition, Gardner criticized RAND's use of data from 2001 through 2004, saying the study fails to consider that the number of patients visiting EDs for nonurgent reasons has declined in recent years (HealthLeaders Media, 9/8).

Read more: http://www.californiahealthline.org/articles/2010/9/8/study-many-ed-visits-could-be-handled-by-urgent-retail-clinics.aspx#ixzz0yyg2PgeY

19. Effectiveness of additional supervised exercises compared with conventional treatment alone in patients with acute lateral ankle sprains: systematic review

van Rijn RM, et al. BMJ 2010; 341:c5688

Objective: To summarise the effectiveness of adding supervised exercises to conventional treatment compared with conventional treatment alone in patients with acute lateral ankle sprains.

Design: Systematic review.

Data sources: Medline, Embase, Cochrane Central Register of Controlled Trials, Cinahl, and reference screening.

Study selection: Included studies were randomised controlled trials, quasi-randomised controlled trials, or clinical trials. Patients were adolescents or adults with an acute lateral ankle sprain. The treatment options were conventional treatment alone or conventional treatment combined with supervised exercises. Two reviewers independently assessed the risk of bias, and one reviewer extracted data. Because of clinical heterogeneity we analysed the data using a best evidence synthesis. Follow-up was classified as short term (up to two weeks), intermediate (two weeks to three months), and long term (more than three months).

Results: 11 studies were included. There was limited to moderate evidence to suggest that the addition of supervised exercises to conventional treatment leads to faster and better recovery and a faster return to sport at short term follow-up than conventional treatment alone. In specific populations (athletes, soldiers, and patients with severe injuries) this evidence was restricted to a faster return to work and sport only. There was no strong evidence of effectiveness for any of the outcome measures. Most of the included studies had a high risk of bias, with few having adequate statistical power to detect clinically relevant differences.

Conclusion: Additional supervised exercises compared with conventional treatment alone have some benefit for recovery and return to sport in patients with ankle sprain, though the evidence is limited or moderate and many studies are subject to bias.

Full-text (free): http://www.bmj.com/content/341/bmj.c5688.full

20. Faulty Estimates of Patient Weight Affect tPA Dose in Stroke

Pauline Anderson. November 18, 2010 — About half of stroke patients cannot communicate their body weight (BW), only 1 in 5 relatives are able to provide this information, and a physician's or nurse's visual estimation of a patient's weight is often inaccurate, according to a new study.

The Weight Approximation In Stroke before Thrombolysis (WAIST) study further showed that about a third of patients received an inaccurate dose of tissue plasminogen activator (tPA) based on these faulty weight estimates.

Although overdosing did not increase the risk for symptomatic intracerebral hemorrhages (sICHs) in this small study, underdosing was a strong predictor for worse clinical outcome, researchers report.

Results of the WAIST study were published online November 11 in Stroke.

The results with regard to the outcome of overdosing should be viewed in context, cautioned the study's lead author, Martin Köhrmann, MD, associate professor of neurology at the University of Erlangen-Nuremberg, Germany. He stressed that this was a single-center pilot study that was undertaken to estimate the power needed for a larger-scale trial.

Dosing Crucial

Stroke patients are frequently unable to communicate their weight due to aphasia or decreased consciousness. tPA is given on a milligram per kilogram basis, but there often is not the time or the equipment in the emergency department to verify a patient's weight and determine the correct drug dose. Physicians therefore often rely on "eyeballing" or visual estimation.

"Dosing itself is really crucial for the activity of tPA, and overdosing may be not as useful as the correct dose, and underdosing may cause harm to the patient," said Dr. Köhrmann. "This, together with the situation where we don't have the correct weight information, is really concerning."

The study included 109 stroke patients with a median age of 71 years set to receive intravenous thrombolysis (IVT) at a dedicated neurological emergency room at University Hospital, Erlangen, Germany, between April 2008 and February 2009. About 61% of the subjects were male.

Before tPA administration, 2 physicians, 2 emergency department nurses, and a neuroradiological technician estimated the BW of each patient. All patients were then weighed within 24 hours after IVT. The mean BW was 77.5 kg.

A physician blinded to the BW and dosage data assessed the outcome of patients at 90 days.

Patients Unable to Communicate Weight

The study found that 55 patients (50.5%) were unable to provide BW information, and only 20% of their relatives could supply this information. Errors in BW estimation were common: 20.8% among the patients themselves, 38.2% among treating physicians, 42.2% for emergency nurses, and 44.4% for the neuroradiological technician.

Performing anthropometric measurements (height, waist, and hip circumference and body mass index) produced fewer errors: 20% overall (17.9% overestimation and 2.1% underestimation).

For the study, the mean tPA dosage was 0.904 mg/kg. Current guidelines recommend a dose of 0.9 mg/kg. Misdiagnosis was defined as more than 10% above (overdosing) or below (underdosing) the target. About a third (33%) of the patients in the study received inappropriate doses; 17% were overdosed and 16% underdosed.

Nine patients weighed more than 100 kg and received the maximum dose (90 mg). Taking this into account, there was an overall combined underdosage and overdosage in 29% of patients.

No symptomatic hemorrhages were seen in patients receiving too much tPA. A larger percentage of this group reached a modified Rankin scale (mRS) score of 0 to 2 (58.8%) than the correct dosage group (54.9%). However, said Dr. Köhrmann, "to draw the conclusion that overdosing doesn't harm is going beyond the power of our trial."

He pointed out that other research has suggested that overdosing may, indeed, be harmful. "We didn't find that, but that doesn't mean that it doesn't exist."

Significant Impact

Fewer patients not receiving enough tPA reached favorable outcomes (ie, 16.7% had mRS scores of 0-1 and 25% had mRS score of 0-2) compared with the correct dosage group (40.8% and 54.9%, respectively).

"I was surprised to find that even in this small number of patients, there was a significant impact of underdosing on their outcome," said Dr. Köhrmann. "We really have to confirm that in a larger-scale study."

On the basis of these data, he and his colleagues will be able to calculate the power needed to a larger-scale study, said Dr. Köhrmann.

Planning for this study — WAIST II — is already under way. It will be a multicenter study, and the protocol will include weighing patients on a bed scale immediately after starting thrombolysis and adapting the tPA dosage when indicated.

Needs Perspective

In an accompanying editorial, Andrei V. Alexandrov, MD, from the Comprehensive Stroke Center, University of Alabama Hospital, Birmingham, said the finding that tPA overdosing did not increase the risk for sICH needs to be put in perspective.

"It is reassuring to see that inadvertent overdosing of tPA in experienced hands at a busy stroke center did not lead (or at least did not show a trend given relatively small numbers) to increasing risk of sICH," he writes.

However, he noted that the study was small as was the number of ICHs at only 3. As well, sICH decreases are likely due to better patient selection, adherence to protocol, and blood pressure management, he said.

Weighing stroke patients while they're on a computed tomographic (CT) scan gantry could be a "quick and practical solution" to determine correct tPA dosing in stroke patients, he said.

"Why not equip this sophisticated moving console with calibrated scales? Weigh the patient precisely and have this information by the time CT scanning is completed."

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21071723

21. A Special Helmet to Deliver Continuous Positive Airway Pressure in Infants

In a small study, 70% of infants with acute respiratory distress stabilized or improved after 2 hours of helmet CPAP.

For logistical reasons, noninvasive ventilation is particularly difficult to achieve in infants. In a prospective observational study, researchers assessed the feasibility of using a specially designed helmet to deliver continuous positive airway pressure (CPAP) at 6 cm H2O in 23 consecutive infants (age range, 2–8 months) with acute respiratory distress in a pediatric intensive care unit in France.

Helmet CPAP failed in two infants (9%) who had severe laryngeal stridor and required intubation. Sixteen infants (70%) stabilized or improved after 2 hours of helmet CPAP. Scores on a 0- to 15-point newborn pain and discomfort scale stabilized or improved in 96% of infants (median scores improved from 4 at baseline to 2 after helmet use). Pressure sores were detected at the base of the skull within 24–48 hours of helmet use in three of the first six patients, but no incidents occurred after the protocol was changed to place a small cushion in the helmet.

Comment: It makes sense to avoid intubation if airway protection and ventilation can be achieved noninvasively. Although larger studies are needed to confirm an outcomes benefit, use of a helmet to provide CPAP for infants is feasible and worth considering in selected cases when appropriate equipment and monitoring capabilities are available.

— Kristi L. Koenig, MD, FACEP. Published in Journal Watch Emergency Medicine September 17, 2010. Citation: Milési C et al. Continuous positive airway pressure ventilation with helmet in infants under 1 year. Intensive Care Med 2010 Sep; 36:1592.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/20607519

22. Light Reading from BMJ’s Special 2010 Holiday Issue

a. Cunningham AL, et al. Red for danger: the effects of red hair in surgical practice. BMJ 2010;341:c6931

Traditionally, surgeons and anaesthetists regard red haired patients with some trepidation because of their reputation for excessive bleeding, a reduced pain threshold, and an, albeit anecdotal, increased tendency to develop hernias.

Full-text: http://www.bmj.com/content/341/bmj.c6931

b. J Groves. Bicycle weight and commuting time: randomised trial. BMJ 2010; 341:c6801

A lighter bicycle did not lead to a detectable difference in commuting time. Cyclists may find it more cost effective to reduce their own weight rather than to purchase a lighter bicycle.

Full-text: http://www.bmj.com/content/341/bmj.c6801