Tuesday, November 15, 2011

The Cure For Bleeding is More Bleeding?

Intraventricular TPA for intraventricular hemorrhage - I wouldn't call it counter-intuitive, but I would certainly call it unusual.

This is a small placebo-controlled, randomized, blinded, prospective trial enrolling 48 patients with intraventricular hemorrhage requiring placement of an intraventricular catheter for CSF drainage.  They were testing the theory that low-dose TPA would assist in clot breakdown, thus speeding recovery.  There are probably not significant differences between groups - although the placebo group was oddly mostly women.  Also fascinatingly, the predicted mortality of each group was ~74% - and ended up being 23% in the placebo group and 19% in the TPA group.  Serious adverse events including 61% in the TPA group and 36% in the TPA group.  Due to the small sample size of the cohort, none of these differences reached statistical significance.

Unfortunately, the screaming major flaw in this study is that they do not truly have a control group - a true control would be standard care without the use of placebo administration through the intraventricular catheter.  Their rate of ventriculitis (8% and 9%) is higher than the typically expected rate for intraventricular catheter placement (probably below 5%), and is consistent with prior studies that showed increased incidence of ventriculitis when the catheter is used for administration of drugs or irrigation.  So, the safety profile and minimal outcome trend in favor of the TPA group can't truly be evaluated because it isn't being compared to the current standard of care, which is leaving the catheter alone for drainage only.

The authors conclude these results support further evaluation - which is already ongoing in the CLEAR III trial - and that the treatment met their pre-defined safety profile cut-offs.  Unfortunately, yet again, propagating their skew on the data is motivated by financial interests - Johns Hopkins has applied for a use patent and Genentech is behind the rtPA licensing and funding.  

"Low-Dose Recombinant Tissue-Type Plasminogen Activator Enhances Clot Resolution in Brain Hemorrhage"

Sunday, November 13, 2011

Big Pharma Is Behind The Money Hemorrhage

This is a research letter from the Archives of Internal Medicine that received a good deal of press recently, examining exactly where in the health system we were wasting money.

They focused on the ambulatory setting, used the NAMCS/NHAMCS database, and evaluated for the activities identified in the "Good Stewardship Working Group" identified by consensus to be low-yield and unnecessary.  They considered this to include antibiotics for afebrile/non-strep pharyngitis, routine EKGs, CT and MRI for uncomplicated low back pain, DEXA scans for young women, etc.  And they found - and this is where the big story comes in - $6.7 billion in these consensus not-recommended activities.

Fortunately for our Internal Medicine and Family Medicine colleagues, they actually weren't ordering a lot of unnecessary tests - $175 million for low back pain and $527 million for DEXA are a lot of money, but still a drop in the bucket.  The majority of the unnecessary activities, $5.8 billion of the total $6.7 billion, was writing for a brand-name statin (atorvastatin or rosuvastatin) instead of one of the generics.

Certainly just the tip of the iceberg.  Drug reps are more than earning their salaries, apparently.

"'Top 5' Lists Top $5 Billion"

Saturday, November 12, 2011

When Parents Refuse a Septic Workup

This is a brief commentary and discussion regarding the implications of parental refusal of hospitalization and evaluation of a potentially septic neonate.  It is absolutely an issue we all hope to never face, but probably will at some point in our careers.

Two pediatricians offer differing opinions on the extent to which social work and child protective services need be involved, raising such issues as the threshold percentage for likelihood of serious bacterial infection/bacteremia should be for "imminent harm" to the child, and the perceived benefits of therapy.  No specific answers are gleaned from the article, but it is worth reading and thinking through the discussions you would have in a similar situation.

"When Parents Refuse a Septic Workup for a Newborn"

Thursday, November 10, 2011

Ethanol - Miracle Drug (For Stroke)

From China, in Stroke, an animal model (poor rats, as usual) of MCA ischemia, collagenase-induced ICH, and post-TPA ICH.  Rats received either 0.5 mg/kg, 1.0 mg/kg, or 1.5 mg/kg ethanol after two hours of MCA occlusion.  Performance on various foot, balance, and parallel behavioral testing significantly favored the ethanol treatment group with initial and sustained reduction in errors as compared to the no-treatment group.

No difference was found between groups in induced ICH volume, and in their (small) series, no increase in ICH after TPA administration.  A transient increase in expression of hypoxia-inducible factor 1-alpha favoring ethanol was seen at 3 hours after reperfusion, gone by 24 hours.

I cannot wait to see the day where we give IV ethanol for acute stroke.

"Beer, the cause and solution to all the world's problems."

"Neuroprotective Effect of Acute Ethanol Administration in a Rat With Transient Cerebral Ischemia"

Wednesday, November 9, 2011

Computers - Probably Better Doctors for UTI

Uncomplicated urinary tract infections are probably one of the diagnoses that Emergency Physicians handle the worst - if they come to the ER, they're likely to get some sort drawn-out testing, whereas, if they went to their regular physician or called the nurse hotline, there would be antibiotics waiting for them at the pharmacy before they finished talking.

This is a prospective study in which patients with possible UTI were referred to a triage kiosk to complete a standardized computer questionnaire.  624 patients with possible UTI interacted with the kiosk - and unfortunately, only 103 qualified for the study by having enough features of typical, low-risk illness.  Patients were then randomized to protocolized antibiotic prescription as reviewed by a triage physician or usual care.

The good news - the kiosk saved a lot of time (89 minutes vs. 146 minutes).  The bad news - there were only 41 patients  followed-up in the intervention group and 26 followed-up in the control group, so we end up with only a tiny number of patients in each arm.  The kiosk group received more antibiotics for negative urine cultures than the control group (93% vs. 67%), so there is some additional element of harm secondary to antibiotic exposure - and, with a limited protocol, there are potential misses - and this study isn't large enough to identify them.

But, really, uncomplicated, typical UTI symptoms in women shouldn't be rocket science - and you shouldn't necessarily be doing any testing.  I would say the computer is a better physician - except, it would be absolutely simple for a physician to simply narrow their approach to match the efficiency of the kiosk with, in theory, some added skill.

"A Randomized Trial of Computer Kiosk–expedited Management of Cystitis in the Emergency Department"

Tuesday, November 8, 2011

Conflict of Interest in TPA Literature

Another tiny bit of self-promotion - a new publication published today.  Stems essentially from a literature review I did after clawing through ECASS-III and noting that 12 of the 14 investigators were paid, sponsored, or employed by the manufacturers of alteplase - which muddied my estimation of the reliability of the conclusions.  Turns out, ECASS-III wasn't the only one....

"Pharmaceutical Sponsorship Bias Influences Thrombolytic Literature in Acute Ischemic Stroke"

Monday, November 7, 2011

Resident Productivity Does Not Predict ABEM Scores

Simple, single-institution study of 11 years of resident in-service scores, patients-per-hour, and ABEM qualifying examination scores - and, as previously shown, only PGY-3 in-service examination scores predicted ABEM oral and written examination scores.

Simulated oral board examination scores did not correlate with ABEM oral examination scores, and the relative number of patients-per-hour had no significant correlations between any testing.

I would say that bears out my observational experience - doing more has no bearing on whether you might be doing more incorrectly.

"Outcome Measures for Emergency Medicine Residency Graduates: Do Measures of Academic and Clinical Performance During Residency Training Correlate With American Board of Emergency Medicine Test Performance?"

Good luck to everyone taking their ABEM exam today!

Sunday, November 6, 2011

CTA Contrast Probably Increases ICH With TPA

...although the authors of this study draw the opposite conclusion.

In an effort to decrease the administration of TPA to stroke mimics and TIAs, some institutions are moving to the use of CT angiographic and perfusion studies after the initial non-contrast scan.  Previous studies have suggested an association between iodinated contrast administration and ICH after TPA.

These authors beg to differ.  In their study cohort, they retrospectively evaluate 319 patients receiving TPA for acute stroke, 69 of whom receive contrast and 243 who do not.  Depending on whether the ECASS or SITS-MOST definition of symptomatic ICH is used:
 ECASS - 4 of 69 (5.8%) with contrast, 12 of 243 (4.9%) without contrast
 SITS-MOST: 3 of 69 (4.4%) with contrast, 9 of 243 (3.7%) without contrast

...and that small absolute difference does not reach statistical significance because their numbers are so small.  This does not prevent the authors from stating "we found no association of either IV contrast administration or contrast dose with SICH in our series of patients treated with IV rtPA."  They're not wrong - but they barely address how underpowered their study is, or how every baseline characteristic (age, stroke severity, comorbid conditions) favored their contrast group, yet they still trended towards increased ICH.

Does the author of every TPA article live in a distortion field that blinds them to reasonable consideration of safety issues and study limitations?

"Iodinated Contrast Media and Cerebral Hemorrhage After Intravenous Thrombolysis"

Friday, November 4, 2011

Predicting Deterioration After Admission

This is a decidedly unsexy topic that I guarantee your Medical Director or QI committee cares about a lot.  Particularly where I work, we occasionally have a prolonged boarding event, the patient isn't reassessed in a certain time frame, the patient is transported out of the ED - and they arrive on the floor or step-down and Rapid Response is called for an unanticipated escalation in care.

This is apparently a bigger deal in the United Kingdom, because it is recommended by their government hospital body to employ a risk-stratification system to predict patient deterioration.  These two articles discuss the derivation in the UK and the validation in Canada of the "ViEWS" score, which is named in part by from their electronic health record that stores their physiologic data.  The general gist of the system is that the authors of the first article derived a score incorporating pulse, respiratory rate, temperature, systolic BP, O2 saturation, whether patient was on oxygen, and a measure of CNS alertness.  They then compare it do several other scoring systems and amazingly enough, the scoring system they derive - using the system from the company the authors' wives work for and in which they own shares of stock - works better than the other systems.

An abbreviated version of this is put into validation at a Canadian hospital that does not use any of the equipment, or have any financial conflict of interests.  They found equally good results - which, in summation they give as four risk-stratification groups:
 - < 3 points: 65% of all patients, only 0.02% died within 48 hrs.
 - 3-6 points: 28% of all patients, 0.41% died within 48 hrs.
 - 7-10 points: 6% of all patients, 3% died within 48 hrs.
 - >11 points: 0.7% of all patients, 13.8% died within 48 hrs.

So, yes, we all can probably look at the patients scoring >11 and know they're sick without a scoring system.  However, this might be a model to look at with nursing staff to help change the parameters for floor beds or to reassess which patients can be downgraded in order to free up more intensive resources upstairs.  Just don't necessarily buy the product being hawked by the original authors.

"ViEWS—Towards a national early warning score for detecting adult inpatient deterioration."

"Validation of an abbreviated VitalpacTM Early Warning Score (ViEWS) in 75,419 consecutive admissions to a Canadian Regional Hospital"

Thursday, November 3, 2011

Medication Errors During Resuscitation

According to previous literature from 2002, up to 19% of medication doses are administered in error to hospitalized patients.  Presumably, we've improved.

Apparently, we haven't.  This is a prospective observational study by pharmacists in Pittsburgh who observed the inpatient Medical Emergency Team in operation - which in this instance, was a physician-led team with "full" critical care capabilities, as opposed to their non-physician Rapid Response Team.  They observed medication administration during 50 of these calls and found that there were 1.6 errors per medication administration.  Yes, they really observed more than one error per dose - but 66% of those issues involved aseptic technique.  Subtracting those, they observed an error merely every other dose.  46% were prescribing errors, 28% administration technique, 14% mislabeling, 10% preparation, and 2% improper doses.  The authors eventually conclude that 14% of the total non-aseptic errors were truly harmful, not just "errors".

Despite the small sample size, I think it's a fair assessment that "medical emergency" situations can be chaotic and error-prone - and we still have a ways to go to implement systemic changes to prevent errors.

In the end, the pharmacists' solution is - more pharmacists.  Hmmm....

"Medication Errors During Medical Emergencies in a Large, Tertiary Care, Academic Medical Center"

Tuesday, November 1, 2011

Dabigatran Worsens/Does Not Worsen Bleeding

Stroke and Circulation are both Journals under the umbrella of the American Heart Association.  So, when they publish articles that come to contrasting conclusions, I find that entertaining.

Both of these articles are mouse models of bleeding on dagibatran, C57BL/6 or CD-1 mice.  Sadly, they are frighteningly complex in their adjustments and statistical analyses - which means it defeats my ability to concisely summarize the findings and methods.

In short, one of these articles looks at intracranial hemorrhage after collagenase injection for mice receiving several different doses of oral dabigatran, and compare it to controls, warfarin, lepirudin, fondaparinux, and heparin.  It appears, and the author's final conclusion is, that dabigatran is the least harmful of all anticoagulants - about halfway between controls and the other anticoagulants.  They also shoot the mice with lasers in another portion of the study, and dabigatran "wins" that as well.

The other article looks at trying to reverse dabigatran - which, if you recall the human study I posted a few weeks back, was not successful in humans.  However, human trials were all surrogate markers of bleeding as measured by laboratory measurements of clotting.  What entertains me is, in contrast to the other study, these authors have no trouble inducing bleeding and significant ICH formation with dabigatran.  In any event, once the mice were adequately bleeding, the authors compared prothrombin concentrate complexes (specifically, Beriplex), FFP, and FVIIa for treatment of ICH 30 minutes after induced injury with collagenase.  Happily, PCCs, in a dose-dependent manner, attenuated the induced ICH, while the others failed.

So, perhaps this "novel, reversible" anticoagulant has a treatment option for life-threatening bleeding.  Human confirmation, at least case reports, needed.

"Anticoagulation With the Oral Direct Thrombin Inhibitor Dabigatran Does Not Enlarge Hematoma Volume in Experimental Intracerebral Hemorrhage"

"Hemostatic Therapy in Experimental Intracerebral Hemorrhage Associated With the Direct Thrombin Inhibitor Dabigatran"

Monday, October 31, 2011

Sodium Polystyrene Sulfonate For Lithium Toxicity

This one is for @drsamko, thanks to his tweet yesterday.  

The most recent of 19 articles in pubmed for the search "sodium polystyrene sulfonate lithium", a retrospective cohort review looking at the use of SPS in the treatment of lithium toxicity.  Given that lithium and potassium are similarly charged cations, multiple animal studies evaluated its use in lithium overdose, but only case reports in humans.  These authors reviewed 9 years of cases at their institutions, two hospitals in Montreal, Canada, for the effect on lithium serum half-life between patients prescribed SPS vs. patients who were not prescribed SPS.

They only looked at chronic overdoses admitted for management - 90 patients, 72 chronic, 48 had data points to properly evaluate the half-life.  36 received "standard treatment" and 12 were prescribed SPS.  The authors don't well-describe the standard treatment group, and don't indicate whether any received hemodialysis - but I get the impression the treatment for chronic toxicity only employs HD on rare occasions of renal failure.  Of the 12 that received SPS, most simply received IV hydration and observation in addition to SPS - and one received hemodialysis due to renal failure.  Half-life of lithium in the controls was 43 hours compared to 20.5 hours in the SPS-receiving group.

SPS isn't totally benign - there was mild hypokalemia in half their treatment population - and in rare cases it causes intestinal necrosis.  And, considering chronic lithium toxicity generally has a benign course, you could go either way.  You can certainly argue that decreased hospital length-of-stay is a significant financial and health benefit and justify giving it, though, so it's worth knowing about.

"Successful treatment of lithium toxicity with sodium polystyrene sulfonate: a retrospective cohort study"

Saturday, October 29, 2011

Novel Ischemia Prediction from CCTA

One of the arguments against CCTA is that it only describes coronary anatomy - and has no demonstrated clinical predictive value regarding whether the observed lesions are flow-limiting or potentially related to anginal symptoms.  This study develops a computational fluid dynamics model that attempts to predict flow through coronary stenoses seen on CCTA.

Korea, Latvia, and California come together to evaluate 103 patients in a multicenter trial in which patients with suspected CAD underwent CCTA, invasive coronary angiography, and fractional flow reserve measurement.  They used only 256 and 64-slice scanners for CCTA, and CAD was quantified as none, mild (0-49%), moderate (50-70%), and severe (>70%).  Patients then underwent invasive coronary angiography where ischemia-related flow-limitation was defined as a fractional flow reserve of < 0.80.  The study group then developed a method of deriving the FFR from CCTA data, and compared it to the actual measurements from invasive coronary angiography using the same threshold value.

The conclusions from this article depend what takeaways you're looking for.  On one hand, the FFR-CT method was pretty decent - 87.9% sensitive and 82.2% specific regarding their definition of ischemia-causing lesions.  The other real takeaway is that CCTA has abysmal performance at the threshold typically used in the CCTA studies of >50% stenosis.  Their calculated +LR for CCTA stenoses >50% was only 1.51 in the setting of a specificity of 39.6%.  To me, another nail in the coffin showing CCTA is the d-Dimer of CAD, leading to a ton of unnecessary testing.

Considering it took them 5(!) hours to generate the FFR-CT measurement based on Newtonian fluid and Navier-Stokes equations on a parallel supercomputer, I don't think we'll be seeing this anytime soon - but hope is out there for the future.

"Cardiac Imaging Diagnosis of Ischemia-Causing Coronary Stenoses by Noninvasive Fractional Flow Reserve Computed From Coronary Computed Tomographic Angiograms"

Friday, October 28, 2011

Soft Drinks & Youth Aggression

This is not an EM article - but it was too bizarre to pass up.  Apparently, the use of soft drinks and junk food is a validated legal strategy for justifying homicide (e.g., the 'Twinkie Defense') - and this study finds an association to support it.

2,725 Boston high-school students surveyed regarding non-diet soft drink use and violence towards peers, dates, children, or firearm use.  Attempting to control for other factors, they eventually find statistically significant associations between youths who drink >5 cans of soft drinks in a week and increased alcohol use, increased tobacco use, as well as all categories of violence.  In fact, with all four categories of violence, the incidence of each increased in a dose-dependent manner with soft drink consumption.

This is, of course, an observed association, not necessarily a causal relationship, although the authors speculate on how sugars and caffeine might incite aggression.  If you are the parent of a high-school student, it isn't necessarily going to prevent violence to deny them access to non-diet soft drinks - but, if your high-school student is a heavy soft drink consumer, look out!

"The ‘Twinkie Defense’: the relationship between carbonated non-diet soft drinks and violence perpetration among Boston high school students."

Wednesday, October 26, 2011

Do/Don't Scan the Trauma Patient

In a study attempting to build consensus, they discovered philosophical differences between the trauma team and the emergency physician.

This is a prospective observational study in which 701 blunt trauma activations at LAC-USC were enrolled, with the EP and the trauma team each giving an opinion on which CT studies were necessary.  The authors then reviewed which scans were obtained, sorted out the scans that were undesired by one or both physicians, and determined whether any injuries would be missed.

Bafflingly, 7% of the 2,804 scans obtained during the study period were deemed unnecessary by both the emergency physician and the trauma attending - yet were still performed.  The remaining 794 undesired scans were desired by the trauma team but not the emergency physician.  Their question - would anything of significance been missed if the scans had been more selectively ordered?

The answer is - yes and no.  The trauma surgeon authors state yes, and justify that by saying that many of the abnormalities missed on CT required closer monitoring - just because none of the missed injuries deteriorated during the study period does not mean they were not significant.  The emergency physician authors point to a 56% reduction in pan-scanning, the benefits of radiation and cost reductions, and hang their hats on the fact that none of the hypothetically missed injuries changed management.

So, who is right?  Both, and neither, of course.  Emergency physicians and trauma teams should work on developing evidence-based clinical decision rules to support selective scanning in blunt trauma - and then try this study again to see if they can generate results they can agree on.

Definitely a fun read.

As far as medical literature goes, of course.

"Selective Use of Computed Tomography Compared With Routine Whole Body Imaging in Patients With Blunt Trauma."

Tuesday, October 25, 2011

ECMO For Influenza

Not many institutions in the U.S. are set up for ECMO in adults, particularly in the Emergency Department, but there are several small datasets out there indicating it should be a significant part of our arsenal for selected patients.  This is a review of ECMO's use in H1N1 influenza-associated ARDS in England during the "Swine Flu" pandemic.

The authors retrospectively reviewed 80 patients with H1N1 from prospectively collected cohort data, all of whom required critical care for ARDS and were referred for ECMO in the United Kingdom.  Through some data calisthenics, these 80 patients were compared to matching subgroups of patients out of 1,756 in the H1N1 critical care cohort.  Of the 80 patients referred for ECMO, only 69 actually received it.  However, when compared to these 80 patients in an intention-to-treat analysis, there was a significant survival advantage associated with referral to ECMO - approximately 24% mortality in the ECMO-referral group compared to 46-52% in the matched controls, depending on which method they used to identify matched controls.

Not a big stretch to interpret this as a positive treatment association for ECMO in H1N1-associated ARDS.  But, I'd still get your flu shot.

"Referral to an Extracorporeal Membrane Oxygenation Center and Mortality Among Patients With Severe 2009 Influenza A(H1N1)"

Sunday, October 23, 2011

EMS Blood Pressures Aren't Unreliable

Ever since a trauma patient billed as normotensive with stable vital signs rolled off the elevator with CPR in progress having "just lost pulses", I've been somewhat skeptical of my prehospital report, including vital signs.  This study, at least, supports a position that, barring untruthfulness, EMS providers vital signs are usually not clinically significantly different than vital signs obtained on arrival to the Emergency Department - even if observed techniques for EMS providers weren't perfect.

The first phase study looked at 100 patients arriving in the Emergency Department.  BP measurements were obtained within 5 minutes of arrival, and compared to the reported measurement from EMS.  There was approximately a 17mmHg +/- spread to the systolic pressures measured by EMS compared to the first BP in the Emergency Department.

The second phase of the study had observers riding with EMS and documenting the technique at which they used to find vital signs - and then having the research assistants performing the same measurement in the field as well.    In this phase, EMS providers systolic pressure was only a 10.1mmgHg +/- spread away from the research assistant - despite having ideal technique deficiencies and a terminal digit preference for numbers ending in zero.

The article concludes that EMS providers measurements had poor agreement with subsequent measurements, and that the differences were clinically significant.  However, based on the distribution of error in their Bland-Altman plots, I disagree that assessment, as most of the variability occurred throughout a range of inconsequential systolic pressures between 120 and 170.  They unfortunately had very few patients with clinically important hypo- or hypertension, so the question really remains unanswered whether EMS measurements at the clinically important extremes are reliable.

I do find it rather entertaining that their methods included a "specially trained research assistant" to measure blood pressure, referred to in the title as an "expert".  You can be an "expert" in anything nowadays, apparently.

"Agreement between emergency medical services and expert blood pressure measurements."

Saturday, October 22, 2011

A Third of TPA Patients Do Not Have Stroke

...but they almost all do well!  Only 5.1% of patients without stroke who receive TPA end up with intracerebral hemorrhage - so it's OK that we give TPA to a ton of patients without a confirmed diagnosis of stroke, right?

This is a retrospective Finnish registry study of 1,104 consecutive TPA patients enrolled in a prospective cohort.  Of these, 119 had basilar artery occlusion, which is angiographically proven prior to treatment, and are excluded from their analysis, and a couple others were excluded for other reasons.  This left 985 patients who were initially diagnosed with ischemic stroke, and, eventually, 14 of those patients were diagnosed as a stroke mimic such as migrane, epilepsy, or a demyelinating disorder.  The authors then go on to say that stroke mimics such as these accounted for a mere 1.4% of all TPA patients, and none of them had ICH.

But, this isn't exactly a true reading of their data.  The authors also state that 275 of their patients had "neuroimaging negative ischemic stroke", which is to say, their follow-up MRI detected no sign of infarct.  Now, there is a false-negative rate on DWI MRI for stroke, but it's in the range of 5% for acute infarcts, and generally involves small lacunar, small cortical, and some posterior circulation strokes.  Not only that, it's reasonable to suggest that around 40% of TIAs actually have DWI or FLAIR sequence abnormalities as well.

So, some of their "neuroimaging negative ischemic stroke" group probably does have ischemic stroke with false negative MRI - but not 30% of the study population.  And, some of their neuroimaging positive group is likely false positive from TIA as well.  These numbers for stroke mimics are also far below other reported case series, which have estimated 10-30% incidence, depending on whether TIAs are included.

I absolutely cannot fathom this line of reasoning and distortion Neurology is developing in justify recklessly pushing TPA onto a larger population.

"Stroke Mimics and Intravenous Thrombolysis"

Thursday, October 20, 2011

Preventing Mechanical Ventilation in Newborns

This is lovely article regarding the treatment of respiratory distress in newborns.  It is not a new concept to use surfactant in clinically indicated situations to improve ventilation in the newborn in distress - however, the typical treatment involves endotracheal intubation and mechanical ventilation prior to application.  This is a randomized, controlled trial of surfactant administration prior to mechanical ventilation.

This involves 220 preterm infants in Germany who were selected for the trial, essentially, if they were on CPAP requiring more than 30% inspired O2.  In the intervention group, patients received intratracheal surfactant if stable on CPAP and 30% O2.  Outcome measures were the portion of patients mechanically ventilated at any time or at day 2 or 3 after birth.  Minimal differences between groups, although the control group was a few grams lighter at birth.

Overall, 33% of all intervention infants required mechanical intervention vs. 73% of the control group.

Simple takeaway - surfactant isn't just useful after intubation, but may also prevent mechanical ventilation.

"Avoidance of mechanical ventilation by surfactant treatment of spontaneously breathing preterm infants (AMV): an open-label, randomised, controlled trial"

Wednesday, October 19, 2011

Ultrasound In Undifferentiated Infant Vomiting

Is there anything ultrasound can't do?  Trauma, vascular access, undifferentiated abdominal pain - and another nice case report for vomiting in children.

These authors are using ultrasound in the projectile-vomiting infant looking at the pylorus, and, after finding a normal pylorus, they scan the rest of the abdomen.  Lo and behold, they identify intussusception.  I am not entirely certain I would be able to well-identify the pylorus, but I can definitely see potentially noting the intussusception.  The authors include several nice images as teaching points.

As the barriers to routine ultrasound use in the ER decrease, hopefully we will all become more facile with using it in many more clinical situations.

"Use of Emergency Ultrasound in the Diagnostic Evaluation of an Infant With Vomiting"

Monday, October 17, 2011

Hypertonic Saline In Cardiac Arrest

There is a physiologic phenomenon observed in animal studies that a small increase in plasma osmolarity using hypertonic saline increases microperfusion, including myocardial and cerebral blood flow.  Therefore, in theory, hypertonic saline administration during resuscitation from cardiac arrest should be efficacious in improving survival and neurologic outcome.

These authors conduct a randomized prospective trial in which they prove that 100 patients in each arm is not enough to make valid claims about a secondary endpoint for which the study was not designed to evaluate.  There is no difference between groups in mortality - and not even non-significant trends - but a small, significant, absolute difference in neurologic impairment, 4.9% without neurologic impairment in the control group and 13% in the intervention group.

So, another study suggesting further study is needed.  If anything, it demonstrates how impossibly hard it is to evaluate treatments in the heterogenous population of out-of-hospital cardiac arrest, and to ensure internal and external validity.

"Randomised study of hypertonic saline infusion during resuscitation from
out-of-hospital cardiac arrest."

Sunday, October 16, 2011

Stroke After-Care Is Far More Important

Somewhere in the rush to but up billboards and focus the medical establishment on experimental revascularization interventions for acute stroke (e.g., time is brain), we've overlooked what truly matters - follow-up care after the ischemic event.  This is a lovely study that reminds us of what we probably knew once, but have forgotten - that even in the absence of acute therapy, simple protocols to prevent fever, prevent hyperglycemia, and prevent aspiration pneumonia lead to profound differences in the number of patients with zero or minimal disability after stroke.

This is a prospective interventional study in which acute stroke units in New South Wales Australia were randomized to either no protocolized intervention, or an intervention with nursing protocols named above.  At the end of the three-year intervention period, 42% of the control group had mRS 0 or 1 at 90 days, and 58% of the intervention group had mRS 0 or 1 at 90 days.  There were small differences in the type of stroke, education level, and prior ability to work that probably favored the intervention group, but the differences at baseline were far smaller than the magnitude of the treatment effect.  In short, a basic nursing protocol intervention improved outcomes more than any other intervention for acute stroke.

"Implementation of evidence-based treatment protocols to manage fever, hyperglycemia, and swallowing dysfunction in acute stroke (QASC): a cluster randomised controlled trial."