I listened to a podcast by Dr Jason
Frank presented on the International Clinical
Educator Network. The discussion reviewed an article on educational
strategies to improve clinical reasoning. The article in question didn't
discuss how they chose their strategies, or which strategies are most
effective, so I don't think that the discussion can be appreciated in a
meaningfully empirical manner. However there are strategies for teaching, and learning, covered in this podcast. The discuss focuses on 7
concepts of teaching:
Dual processing Model: The rapid interpretation of information through heuristics; and the slow analysis of novel information, with strategies to help learners switch between
the two.
Conscious competence model: The movement from unconsciously incompetent to differing
levels of competence. There is a great discussion about how peer learning, and how being able to remember being a new learner is a valuable tool for teachers.
Knowledge Organization: Different tools to structure knowledge of illness to
typical presentations and the diagnoses.
Data Gathering and Data
Processing: The use of standardized
approaches and mnemonics to guide history taking and physical assessment, and
how to filter through information to decide what information is pertinent to
the clinical presentation.
Metacognition: Different ways to approach how you're reasoning through a
clinical encounter.
This is a relatively quick podcast,
the strategies for teaching are easily applied to learning. I think clinical
reasoning is something that is continually perfected, and that there's
something here for all learners.
There was a study published in the BMJ by Lyle Moncur et
al., that examined the correlation between the socio-economic deprivation of a
neighborhood in which a cardiac arrest occured and the rate of bystander initiated CPR. Moncur et al., did this by
examining all OHCA registered with the North East Cardiac Arrest Network to determine
how often bystander CPR was initiated, and the neighborhood in which the arrest
occurred. The address was referenced to the Office of National Statistics to
determine the level of socio-economic deprivation of the neighborhood (1 most
deprived; 5 least deprived). The team was then able to compare the rates of
bystander CPR by socio-economic neighborhood. 
There were 3862 OHCA calls
screened for this study, 683 were excluded because of missing data. What the
team determined is that as economic deprivation increase, rates of
bystander CPR decrease: they found that CPR was initiated by a bystander nearly
40% as often when it occurred in an affluent neighborhood. These results are
sad, but they`re certainly not new. Similar studies were performed in the US
and Asia, showing similar results: as poverty increases bystander CPR
decreases, they also cited differences in racial composition of neighbourhoods
as a possible factor for differences in rates of bystander CPR. This study
however was performed in an ethnically homogeneous region (>95% white), on a
homogeneous patient population (96% white); and as such they're able to exclude
race as a confounding factor. The study doesn't attempt to explain why this
relationship occurs, although lack of access to training was cited as a
potential cause. From a nursing perspective this will likely not impact in-hospital care of poor patients; but it may suggest that targeting CPR education
to poor neighborhoods could be an effective public health mandate.
Justin Morgenstern from First10EM posted a review of managing patients with anaphylaxis. He starts with the obligatory cry of "give the IM Epi stat!": something that still takes on average way too long. Morgenstern then discusses some possible approaches to manage both difficult airways, as well as patients with developing angioedema. There is a good review of shock, with some links to push dose mixing charts, management tips for special populations and a "Dirty Epi Drip" set up. This is a great review for nurses, as Morgenstern makes suggestions not only on medical practice; but also on priorities of care for nursing. Great to see FOAMed that includes the whole care team!
Dr. Rebecca Schroll et al., published a study in the Journal of Trauma Acute Care Surgery earlier this year that compared the outcomes of military and civilian patients who were treated with tourniquets by pre-hospital providers for extremity trauma. This study retrospectively examined the records of patients treated with pre-hospital tourniquets from 9 level one trauma centers in the US and compared them to a prospective military study examining patients treated pre-hospitally with tourniquets during the Iraq war.Schroll et al., reviewed the charts of patients meeting inclusion criteria (>18 years old with extremity trauma treated by tourniquet) and examined them for mortality, effectiveness of tourniquet at controlling hemorrhage, change in SBP after tourniquet application, and complication rates. 197 patients met the inclusion criteria; the average patient was a 39.4(±1.1) year old male (85.8%) with a penetrating injury (56.3%) and ISS of 11. Tourniquets were successful for controlling hemorrhage 88.8% of the time, the overall mortality rate was 3.0%, the average complication rate was 32.4%, with 18.3% of patients requiring amputation.
The results were then compared to a seminal study of combat application tourniquets in Iraq performed by Kragh et al., in 2009, to determine how civilian tourniquet use compared to military use. Schroll et al., determined that the use of tourniquets in the civilian context tended to have better outcomes than the group from the Iraq war study; with both mortality (3 vs. 11%), and amputation rates (18.8 vs 41.8%) being lower. These are impressive statistics, and would seem to suggest that tourniquet use for extremity trauma is safe. They're especially impressive considering that 20% of the patients in the Schroll et al., review were treated with improvised tourniquets that were either self or bystander applied, with "no difference in the incidence of other complications".There are however a few claims made by the authors that I think are overstating the level of this evidence. The study design is weak: there was no control arm to compare outcomes against, there was no discussion on which commercial tourniquets were used, or the indications for using them. The patients in this cohort have drastically different mechanisms from the military cohort; all of whom had blast injuries, tended to be more severely injured, and were being treated in an austere environment (compared to a level one trauma center). The military cohort is also missing key information about limb injury severity and time to "definitive" care, limiting the extent to which the groups can be compared. The claim that improvised tourniquet use had comparable results with no difference in complication rates is also questionable. The that total tourniquet time for this subgroup is unknown, and that the group treated with non-purposed tourniquets had a three fold rate of ischemic/reperfusion injuries (3/40 [7.5%] vs. 4/157 [2.5%]). The suggestion that improvised tourniquets were safe and effective is contrary to previous observational studies that noted higher error rates, and the need for tightening or application of commercial tourniquets when improvised tourniquets were used (see weekly review 1).
I think this research is important, it's the largest of it's type in the civilian context, and in general I think that the evidence supports the use of tourniquets in the civilian context. I don't think that the patient populations were homogeneous enough for this research to be used as a comparison to the Baghdad study by Kragh et al., and would not attempt to extrapolate their findings to the civilian context. I would also disagree with the claim that improvised tourniquets are safe and effective, there were too few patients recruited to make that claim and the outcomes (though underpowered) actually show a three fold increase in risk.
From a nursing perspective I think that this is weak evidence showing that tourniquets are safe for extremity trauma in general. It also shows that a large number of patients will present with improvised tourniquets, and these will need to be assessed as venous only tourniquet can actually speed exsanguination.
http://www.ncbi.nlm.nih.gov/pubmed/26091308
http://www.emdocs.net/neonatal-resuscitation/
No comments:
Post a Comment