As authors of a previous report about serious injuries that occurred
during an extreme sports obstacle course in the U.S. (1), we read with
interest the article by Alana Hawley, etal describing injury and illness
outcomes in a series of Canadian obstacle course events. (2) In this
Canadian study a small percentage of participants presented to onsite
medial services; the majority of complaints were minor and musculoskele...
As authors of a previous report about serious injuries that occurred
during an extreme sports obstacle course in the U.S. (1), we read with
interest the article by Alana Hawley, etal describing injury and illness
outcomes in a series of Canadian obstacle course events. (2) In this
Canadian study a small percentage of participants presented to onsite
medial services; the majority of complaints were minor and musculoskeletal
in nature. Only 2% of those treated were transferred to hospital through
EMS which is consistent with other types of mass gathering events. This
is in sharp contrast to our report in which over 100 EMS (advanced life
support calls) were activated on a single race. Social media drives
continued interest in these outcomes, and as authors, we were surprised by
the robust response of interest by a variety of media outlets in our 2014
manuscript. Particularly as these events become more popular
internationally, we just ask participants and readers to exercise caution
before they are left with the impression that these events are safe. Other
than the identified limitations that the Dr Hawley and her study team
expresses, it should be noted that they studied ONLY Mud Hero obstacle
courses. According to the Mud Hero frequently asked questions, (3) the
obstacles in these races have both hard and easy options and they do not
expose their participants to barbed wire, ice baths, or electric shocks.
The electrical shock injuries were the most severe type (myocarditis,
cerebrovascular accident) that we reported in our study. Ideally those in
the medical profession preparing for an event in their area would
determine the type of obstacles that will be used in the race, and
organize the appropriate EMS support. Likewise, participants preparing
for obstacle races should recognize the potential for increased personal
risk in those that have more dangerous obstacles (such as electrical
shocks).
(1) Greenberg MR, Kim PH, Duprey RT, etal. Unique obstacle race injuries
at an extreme sports event: a case series. Ann Emerg Med. 2014;63:361-6.
(2) Hawley A, Mercuri M, Hogg K, Hanel E. Obstacle Course Runs: Review of
Acquired injuries and illnesses at a Series of Canadian events (RACE)
Emerg Med J (online ahead of print) 9/15/2016
(3) Mud Hero Frequently Asked Questions. http://www.mudhero.com/en/faqs/
Accessed 09/20/2016
We agree that as a retrospective study that compares head injured
patients presenting within and after 24 hours of injury that have
undergone CT imaging our study does have limitations. However, there are
currently few data to guide clinicians in this area. We found only 2
other retrospective cohort studies and an abstract that assessed such
patients in a recently pu...
We agree that as a retrospective study that compares head injured
patients presenting within and after 24 hours of injury that have
undergone CT imaging our study does have limitations. However, there are
currently few data to guide clinicians in this area. We found only 2
other retrospective cohort studies and an abstract that assessed such
patients in a recently published systematic review {1}. Our study is the
first to directly compare patients presenting late after injury with those
who don't, to our knowledge, and includes novel findings.
We agree that it is not possible to estimate the overall prevalence
of significant traumatic brain injury in head injury patients presenting
after 24 hours of injury from our study. However, our study shows that in
patients that undergo CT imaging the prevalence of significant injury is
similar in patients presenting within and after 24 hours of injury. The
yield from the CT scans performed suggests a similar relation between risk
of pathological finding and clinician behaviour, but agree the denominator
for those attending late would be needed to confirm this. Our key finding
is that absence of NICE guideline indications may not reliably exclude
significant injuries in patients presenting after 24 hours of injury.
We agree with Richard Body (Associate Editor) when he opines that the
findings of our study probably call for further research. A prospective
study that evaluates all head injured patients presenting late and
identifies the risk factors that predict significant injury would inform
clinician gestalt. This, in turn, would likely reduce the risk of missing
significant injuries in what appears to an important sub-group.
1. Marincowitz C, Smith CM, Townend W. The risk of intra-cranial
haemorrhage in those presenting late to the ED following a head injury: a
systematic review. Systematic reviews 2015;4(1):165.
I thank the authors for highlighting an ongoing concern I have with
NICE head injury guidance - namely that the guidance is based on studies
of acute head injuries presenting soon after injury and doesn't take
delayed presentations into account.
However my concern would be the reverse of their own as I feel if we
adhered to NICE guidance in patients presenting after 24 hours we would be
performing large numbers of unnece...
I thank the authors for highlighting an ongoing concern I have with
NICE head injury guidance - namely that the guidance is based on studies
of acute head injuries presenting soon after injury and doesn't take
delayed presentations into account.
However my concern would be the reverse of their own as I feel if we
adhered to NICE guidance in patients presenting after 24 hours we would be
performing large numbers of unnecessary investigations for very low yield.
I cannot help but feel that the entire premise of this paper and
conclusions reached are incorrect simply because they look at the wrong
cohort.
The paper examines those patients who underwent a CT of their head
and compares between the delayed presentation and early presentation
(greater and less than 24 hours respectively) and those that had a NICE
indication and those that didn't.
This is easy data to collect retrospectively and analyse but not the
most appropriate.
What is far more valuable is to know what happened to ALL the
patients presenting post head injury - not just those who were selected
for a CT. This is far more challenging data to collect due to coding
issues, quality of note keeping and the vastly higher number of patients
involved.
Conclusions such as clinicians being aware that 'application of NICE
guidance to those presenting >24hrs misses a high proportion of
injuries, clinicians appear aware of this and so are more likely to
request a CT even though no NICE indication is present' appear invalid. We
do not know what proportion of patients with a head injury presented
before and after 24 hours we only know those that had a CT performed. The
clinicians themselves had already selected a group based upon a
combination of NICE guidance and gestalt.
We can best evaluate the sensitivity and specificity of the NICE
guidelines for patients presenting after 24 hours by looking at the
unselected head injured patients presenting to the ED. If we evaluate
those who a clinician had seen and ordered a CT head on then all we can
really comment on is the positive and negative predictive value of the
guidelines in the ED clinician selected patient (which one would hope to
be an inherently higher disease prevalence group).
Whilst I agree that there is somewhat of a lacuna in the guidance
when it comes to delayed presentations of head injuries, clinical gestalt
is key rather than the use of NICE guidance.
The data presented does not in my view show a distinct risk profile for
those presenting after 24 hours with a head injury (as stated in the
conclusions), but instead demonstrates that the negative predictive value
of the 2007 NICE Head Injury guidelines in patients at Hull Royal
Infirmary who had a CT after presenting >24 hours after head injury to
be lower than in those presenting <24 hours after head injury. (7.7%
compared with 9.9%).
Pocock et al present fascinating insight to the challenges of the pre
-hospital environment for undertaking clinical trials (Human factors in
pre hospital research: lessons from the PARAMEDIC trial Pocock H, et al,
Emerg Med J 2016; 33: 562-568) which explain the lack of clear strategies
of the implementation of research protocol on this issue. The need for
strong relationships between teams brings into focus the potenti...
Pocock et al present fascinating insight to the challenges of the pre
-hospital environment for undertaking clinical trials (Human factors in
pre hospital research: lessons from the PARAMEDIC trial Pocock H, et al,
Emerg Med J 2016; 33: 562-568) which explain the lack of clear strategies
of the implementation of research protocol on this issue. The need for
strong relationships between teams brings into focus the potential to
extend this study to incorporate the actions of the first person on the
scene. Recognizing the need for 'normalization' of participation in trails
reflects a similar challenge to find bystander participants to help us
understand lay responder behaviour. Both aspects chime with findings of
research from an earlier point in the pre-hospital care process studied by
the British Red Cross and published in this journal in 2013 (Can first aid
training encourage individuals' propensity to act in an emergency
situation? Oliver E, et al, Emerg Med J 2013 pp.emermed-2012).
The Utstein Formula for Survival (The Formula for Survival in
Resuscitation, Soreide E et al, Resuscitation. 84:1487-1493, 2013) models
the value of medical science as a multiplicative relationship with
educational efficiency and local implementation, yet the volume of
research around how to make education for bystanders effective in order to
guarantee effective intervention is scant. An analysis of the 2015
International Liaison Committee on Resuscitation's 2015 guidelines
identified a lack of research into how best to plan and prepare and how to
recognize an emergency. These crucial gaps need to be filled if bystander
interventions are to be adequate enough for EMS teams to improve their
chances of saving lives.
New guidelines produced by the International Federation of the Red
Cross (International first aid and resuscitation guidelines 2016) include
a new chapter on Education reflecting work to date and incorporating
evidence for improving educational approaches and strategies. Poignant,
though, is the lack of an internationally agreed definition and metric for
effective first aid education. We continue to be severely challenged to
understand the outcome behaviours of lay responders who have been trained
to help and their interaction with the ill or injured. How do we know if
first aid education has been effective? What do we mean by effective
education? And how could we measure it consistently? How do we get a clear
picture of how attitudes and behaviours are related to acquisition of
skills and knowledge?
The volume of medical science relating to emergency response is
substantial. Does such dominance limit discussion on educational
efficiency and local implementation of lay responder strategies? We urge
support for such studies to develop these aspects of survival.
Emily Oliver
Senior Education Research Manager
British Red Cross
eoliver@redcross.org.uk
The comprehensive review by Ramlakhan et al of the effectiveness of
primary care services located within EDs draws mixed conclusions. Whilst
initial efficiency savings were identified (both in terms of GP resource
utilisation and overall cost) and subsequent hospital admission and
referrals appeared reduced, other outcomes proved disappointing or at best
equivocal including length of stay, waiting time and patient satisfa...
The comprehensive review by Ramlakhan et al of the effectiveness of
primary care services located within EDs draws mixed conclusions. Whilst
initial efficiency savings were identified (both in terms of GP resource
utilisation and overall cost) and subsequent hospital admission and
referrals appeared reduced, other outcomes proved disappointing or at best
equivocal including length of stay, waiting time and patient satisfaction.
Given the ongoing critical performance challenges faced by hospitals,
that not only derive from increasing volumes of attendance (whether
through provider-induced demand or otherwise) but also the effect
consequently imposed by inefficiencies and the internal degradation of
pathways, Emergency Departments need to do something radical. The crucial
importance of optimising hospital productivity legitimises the use of
novel streaming services that aim both to minimise the effect on the
hospital of low acuity patients and, specifically, to de-bulk ED Majors
attendance. If a streaming service is to be used, then the same article's
review by Abdulwahid et al identifies the positive impact of senior doctor
assessment at triage. In contrast to the mainly senior ED clinicians that
were reviewed in this paper, our own belief is that senior GPs have a
better chance of deflecting or re-directing potential admissions, not
least because of clinician awareness of community-based options for care.
The introduction of a streaming service to the front door of
Leicester Royal Infirmary (Europe's busiest ED) has aimed to achieve
success using immediate clinical assessment by a senior GP on arrival
followed by rapid assessment using 3 other streaming GPs. In a 6 month
period this small team managed to treat or redirect 19% of all day time
walk in patients that presented (equating to 16,094 patients per year not
entering hospital) while only admitting 5% of patients to ED Majors. This
scale of success in streaming can result in significant performance
advantage for the hospital, both effectively redirecting patients that
could be cared for elsewhere and optimising use of internal pathways and
thereby improving efficiencies.
References:
Ramlakhan S, Mason S, O'Keefe C, et al. Emerg Med J 2016;33:495-503.
Abdulwahid MA, Booth A, Kuczawski M, et al. Emerg Med J 2016;33:504-
513.
Conflict of Interest:
Dr Martin McGrath and Dr Stuart Maitland-Knibb are directors of Lakeside+ Ltd, the company providing the streaming service described at LRI.
I read with interest your recent case report of a perilunate
dislocation. This case highlights the importance of careful assessment of
often complex wrist X-rays.
As a small point, I would however disagree that the 'spilled teacup sign'
is a sign of a perilunate dislocation. This sign is a radiological sign of
a lunate rather than perilunate dislocation.
The key to distinguishing between between both is to first determine...
I read with interest your recent case report of a perilunate
dislocation. This case highlights the importance of careful assessment of
often complex wrist X-rays.
As a small point, I would however disagree that the 'spilled teacup sign'
is a sign of a perilunate dislocation. This sign is a radiological sign of
a lunate rather than perilunate dislocation.
The key to distinguishing between between both is to first determine what
is centred over the radius on the lateral view.
If the capitate is centred over the radius and the lunate is tilted out
with the 'spilled teacup' sign, a lunate dislocation is diagnosed.
If the lunate centres over the distal radius and the capitate is dorsal, a
perilunate dislocation is diagnosed, as your case illustrates.
Murphy-Jones and Timmons described paramedics' experiences of end-of-
life decision making with regard to nursing home residents, including the
challenges faced by paramedics when patients lacked decision making
capacity and the resultant stress from uncertainty about appropriate
treatments. [1] Among the solutions suggested, an essential,
straightforward and well-tested tool for the perplexed paramedic was not
available...
Murphy-Jones and Timmons described paramedics' experiences of end-of-
life decision making with regard to nursing home residents, including the
challenges faced by paramedics when patients lacked decision making
capacity and the resultant stress from uncertainty about appropriate
treatments. [1] Among the solutions suggested, an essential,
straightforward and well-tested tool for the perplexed paramedic was not
available to EMTs in London. Emergency medical providers in the United
States report that that Physicians Orders for Life-Sustaining Treatment
(POLST) Paradigm forms both increase the likelihood that the wishes of
patients with advanced illness and frailty will be honored and decrease
the family and health professional angst of end-of-life decision-making in
moments of crisis. POLST orders have been shown to be effective in
providing clear instructions to emergency medical providers and in making
sure patient wishes at end-of-life are honored -- whether for comfort care
or more intensive treatment. [2] [3] [4]
The POLST Paradigm is an approach to end-of-life planning for those with
advanced illness through a process of shared decision-making between a
patient and his/her health care professional. As a result of these
conversations, patient wishes are documented in a POLST form, [5] which
translates the shared decisions into actionable medical orders, indicating
a patient's wishes regarding treatments that are commonly used in a
medical crisis. As a medical order, emergency personnel - such as
paramedics, EMTs, and emergency physicians - must follow these orders in
the absence of other information. The orders address preferences regarding
cardiopulmonary resuscitation (CPR), other medical interventions such as
intubation and mechanical ventilation, and artificially administered
nutrition. The orders are signed by a physician (and is some jurisdictions
a nurse practitioner or physician assistant) with the concurrence of the
patient or legally recognized decision maker. The POLST form is
distinctive, often brightly colored and can be displayed prominently so
that it can be easily identified by the emergency medical personnel.
The POLST Paradigm has been successfully implemented in the vast majority
of states in the US, and is being adopted in a growing number of
countries. We encourage health systems to adopt and emergency medical
providers who care for patients at the end-of-life to learn more about the
POLST Paradigm and how it can provide medical orders and direction when an
emergent situation faces providers, patients and families. [6]
Arthur R. Derse, MD, JD
Terri A. Schmidt, MD
Susan W. Tolle, MD
[1] Murphy-Jones G, Timmons. Paramedics' experiences of end-of-life
care decision making with regard to nursing home residents: an exploration
of influential issues and factors. ] doi:10.1136/emermed-2015-205405
[2] Schmidt TA, Zive D, Fromme EK, Cook JNB, Tolle SW. Physician
Orders for Life-Sustaining Treatment (POLST): Lessons learned from
analysis of the Oregon POLST Registry. Resuscitation. 2014; 85:480-485.
[3] Richardson DK, Fromme E, Zive D, Fu R, Newgard CD. Concordance of
out-of-hospital and emergency department cardiac arrest resuscitation with
documented end-of-life choices in Oregon. Ann. Emerg. Med. 2014; 63:375-
383.
(4) Schmidt TA, Hickman SE, Tolle SW, Brooks HS. The Physician Orders
for Life-Sustaining Treatment (POLST) Program: Oregon Emergency Medical
Technicians'' Practical Experiences and Attitudes. JAGS. 2004; 52, 1430-
1434.
[5] Oregon POLST Form
http://static1.squarespace.com/static/52dc687be4b032209172e33e/t/56e9951204426272fccd1067/1458148629767/Printing+POLST+instructions+3
-16-2016.pdf Accessed June 17, 2016.
[6] National POLST Paradigm, http://www.polst.org/ Accessed June 16,
2016.
We have read with great interest the review of Ramlakhan et al.
(2016)1 on the effectiveness of co-locating emergency departments (ED) and
primary care centres and the findings of the authors that the evidence is
inconclusive. Yet, we are confident that there are more hints and clues in
the available evidence for policy guidance than was done in the paper by
Ramlakhan et al. (2016). We will illustrate this with a recent po...
We have read with great interest the review of Ramlakhan et al.
(2016)1 on the effectiveness of co-locating emergency departments (ED) and
primary care centres and the findings of the authors that the evidence is
inconclusive. Yet, we are confident that there are more hints and clues in
the available evidence for policy guidance than was done in the paper by
Ramlakhan et al. (2016). We will illustrate this with a recent policy
analysis carried out in Belgium.2 As Burke (2016)3 states in his editorial
it is key to determine the goals of your policy intervention (e.g.
improved access; improved flow; reduced costs; improved patient
satisfaction) and to monitor the implementation of new models. That is
exactly what we have proposed by recommending a 'proof of concept
evaluation' for 24/7 GP posts that are co-located with the ED (with one
entrance and a joint triage area) in order to substitute ED care by
primary care. Indeed, substituting more expensive ED resources by primary
care resources seems a legitimate policy goal.
Belgium has a very high self-referral rate (71%) and a large share of ED
contacts are ambulatory contacts (77%). Furthermore, estimates of
inappropriate ED contacts (40-56%) are higher than the internationally
reported figures of 20-40%.4 As in other countries there is an ever
increasing use of EDs which is in Belgium mainly observed for ambulatory
and self-referred ED contacts. In addition, previous policy measures such
as large investments in out-of-hours GP posts were unsuccessful in
stopping this increasing trend. Most of these out-of-hours GP posts were
not located at hospital sites. In the rare occasions where a GP post was
co-located with an ED they had separate entrances and triage zones not
resulting in substitution.5
Why did our policy recommendation to install GP posts on ED-sites deviate
from the inconclusive findings in the Ramlakhan et al. (2016) review? Our
review of the literature showed that 'design elements' are essential for
successful substitution of ED care by primary care. We believe that these
design elements are insufficiently analysed in the Ramlakhan et al. (2016)
study. In their review several divergent models of co-location were
assessed simultaneously (e.g. nurse-led walk-in clinics instead of GP-lead
urgent care centres; models with separate entrances and triage areas for
the primary care centre and the ED instead of one central entrance and
joint triage area; or even models without a triage function). When
analysing these studies more in-depth, it is clear that these design
elements are making the difference in substituting ED by primary care.
Indeed, 'the devil is in the details'. A difference in prescriptions of
medical imaging and laboratory tests can, for instance, be observed when
the initial triage process was carried out by trained nurses while this
was not the case when triage was done by a receptionist. Moreover, three
recent studies which were not included (van Gils-van Rooij (2015)6 for the
Netherlands; Cowling et al. (2016)7 for England; Eichler et al. (2014)8
for Switzerland) showed that: a co-location of GP posts with one entrance
and joint triage area is effective in reducing the number of self-referred
ED contacts; the largest portion of contacts triaged towards the GP does
only require care from the GP; and that GPs prescribe less medical imaging
and lab tests compared to emergency physicians.
We also acknowledge that the literature is not straightforward. Indeed,
several reviews9 10 illustrated that an expansion of the available
services might unmask latent demand and will increase the overall burden
on the emergency care system even more. However, it cannot be concluded
from the available studies that this increase in activity is caused by
overuse (e.g. shift from regular GP contacts towards urgent care centres)
nor by underuse. To account for these and other potential unintended
effects we recommend a 'proof of concept' evaluation where these (un-
)intended are carefully monitored.
Reference List
1. Ramlakhan S, Mason S, O'Keeffe C, et al. Primary care services
located with EDs: a review of effectiveness. Emerg Med J 2016.
2. Van den Heede K, Dubois C, Devriese S, et al. Organisation and
payment of emergency care services in Belgium: current situation and
options for reform. Health Services Research (HSR). Brussels: Belgian
Health Care Knowledge Centre (KCE), 2016.
3. Burke D. Primary care services located with EDs: a review of
effectiveness. Emerg Med J 2016.
4. Carret ML, Fassa AC, Domingues MR. Inappropriate use of emergency
services: a systematic review of prevalence and associated factors. Cad
Saude Publica 2009;25(1):7-28.
5. Philips H, Remmen R, Van Royen P, et al. What's the effect of the
implementation of general practitioner cooperatives on caseload?
Prospective intervention study on primary and secondary care. BMC health
services research 2010;10:222.
6. van Gils-van Rooij ES, Yzermans CJ, Broekman SM, et al. Out-of-
Hours Care Collaboration between General Practitioners and Hospital
Emergency Departments in the Netherlands. J Am Board Fam Med
2015;28(6):807-15.
7. Cowling TE, Ramzan F, Ladbrooke T, et al. Referral outcomes of
attendances at general practitioner led urgent care centres in London,
England: retrospective analysis of hospital administrative data. Emerg Med
J 2016;33(3):200-7.
8. Eichler K, Hess S, Chmiel C, et al. Sustained health-economic
effects after reorganisation of a Swiss hospital emergency centre: a cost
comparison study. Emerg Med J 2014;31(10):818-23.
9. Ismail SA, Gibbons DC, Gnani S. Reducing inappropriate accident
and emergency department attendances: A systematic review of primary care
service interventions. British Journal of General Practice
2013;63(617):e813-e20.
10. Morgan SR, Chang AM, Alqatari M, et al. Non-emergency department
interventions to reduce ED utilization: a systematic review. Academic
Emergency Medicine 2013;20(10):969-85.
We read with interest the paper by Ramlakhan et al (10.1136/emermed-
2015-204900) on the effectiveness of primary care services located in EDs.
We have just completed a test cycle week of a GP led model for managing
lower acuity patients who present to the Clinical Decisions Unit (CDU) at
the Glenfield Hospital, Leicester; however, we reached different
conclusions. The CDU is a cardiorespiratory unit that receives mixed...
We read with interest the paper by Ramlakhan et al (10.1136/emermed-
2015-204900) on the effectiveness of primary care services located in EDs.
We have just completed a test cycle week of a GP led model for managing
lower acuity patients who present to the Clinical Decisions Unit (CDU) at
the Glenfield Hospital, Leicester; however, we reached different
conclusions. The CDU is a cardiorespiratory unit that receives mixed
acuity urgent patients 24 hours a day from a range of sources (999
ambulance, GP referrals and transfers from both the local ED department
and Urgent Care Centre located on the same site two miles away), but not
self-referrals. The specialist teams are unable to rapidly manage and
discharge low acuity patients because the hospital processes and IT
systems were not designed for this purpose, resulting in overcrowding and
inefficiency. A GP/specialist nurse 'fast track' area was created to
rapidly diagnose (with access to chest x-ray and bloods), and discharge
safely, all patients triaged by experienced nurses at the 'front door' as
potentially fit for same day discharge using the primary care IT system
(SystmOne). 67 patients comprising approximately 30-40% of total
attendances were seen and 88% were discharged (mean of 116 minutes
compared with up to 6 hours at peak periods of activity). No adverse
events or seven day readmissions have been reported. Both patient and
staff satisfaction was high. The overall proportion of patients who left
the department in less than 6 hours (throughput/flow) increased by around
10% easing pressure on specialists who could then focus on the sicker
cohort of patients. GPs handle low acuity problems faster because that
fits in with their training and skill set (they appraise rapidly and
decide). It is a matter of 'right patient in front of the right
clinician'. We are planning a further eight week pilot to consider the
cost effectiveness of our model, greater integration with the local urgent
care system and the best clinician to triage on arrival.
This comparison of non-invasive haemodynamic devices, although
valuable, demonstrates some methodological aspects of the Bland-Altman
method that should be considered to ensure the accuracy of any proposed
conclusions.
The statistical minimum for comparison of two medical device
measurement methods includes reporting mean ?SD values for both methods,
correlation, and Bland-Altman bias and precision, mean % diff...
This comparison of non-invasive haemodynamic devices, although
valuable, demonstrates some methodological aspects of the Bland-Altman
method that should be considered to ensure the accuracy of any proposed
conclusions.
The statistical minimum for comparison of two medical device
measurement methods includes reporting mean ?SD values for both methods,
correlation, and Bland-Altman bias and precision, mean % differences
between methods, and concordance analysis using four quandrant plots if
haemodynamic changes were measured in the same subjects during the
repeated observations.(1) Of critical importance for application of Bland-
Altman statistics is the range of outputs over which the comparison was
made. Repeated measures comparing CO values within a narrow "normal range"
provide little useful information,(2) as the mean differences between
measures will be small and discrimination will be weak. Additionally it is
at high and low outputs that accuracy is the most critical and clinically
consequential.
The authors observed USCOM measures were "considerably" lower than
NICCOMO measures, which were similar to the values they expected. However
the clinical characteristics of the patients are not described, the mean
CO and SVR values or SD were not reported, and no quantitative Bland-
Altman values nor CO ranges presented. Further upon proposing disagreement
between the two methods, no reference was made to normal USCOM reference
values.(3) If any differences existed between the USCOM reference normal
values and the USCOM Green study normal values, then operator error may
have affected the results, and the disagreement is explained, and the
conclusion prefaced with an "in our hands" caveat. Conversely, if the
USCOM values by Green et al. agreed with the previously published normal
USCOM values, and the patient cohorts were substantially clinically
matched, then the conclusion is an error in the measurements by NICCOMO, a
possibility not raised by the authors.
Regardless, this comparison of repeated measures in a single series
of subjects is only designed to demonstrate agreement between two methods,
and not determine which technology is the most reliable, particularly if
the endpoint is attainment of arbitrary and undefined expected values.
Clinical accuracy is related to a more extensive and rigorous series of
comparisons and proofs involving multiple animal and human studies and
comparisons across a range of age groups and clinical applications, and
across wide ranges of cardiac outputs against multiple technologies.
Doppler ultrasound has a long history of reliability and clinical
utility for flow measurements.(4) The USCOM 1A, a transcutaneous Doppler
monitoring technology has been validated against flow probes in animals
across a 6 fold range of outputs during application of inotropes and
vasopressors,(5) and from 0.12L/min to 18.7L/min in humans.(6,7) It has
been validated against invasive standards and non-invasive standards in
approximately 100 studies, and found to provide reliable measures across a
range of outputs and ages.(8,9,10) It has been demonstrated to reliably
measure CI and SVI and detect fluid responsiveness with approximately 90%
sensitivity in patients with AF, free breathing and ventilated patients,
patients on vasoactive and particularly those with dynamic circulation
such as those with sepsis and septic shock where the autonomic nervous
system is active.(11) Further the device is recommended in the paediatric
sepsis guidelines as a means of monitoring disease progress and titration
of therapy,(12) improves outcomes in paediatric septic shock,(13) and has
been recommended as a pregnancy monitoring method for early detection of
pre-eclampsia.(14)
Hodgson et al.,(15) compared inter-rater reliability of stroke volume
measurements at baseline and following passive leg raising measurements,
by emergency physicians and found a 6% error (r=0.96) between measures by
different operators and concluded that "following a training period of
less than 5 h, USCOM stroke volume measurements demonstrated excellent
inter-rater reliability". This confirmed the feasibility of the USCOM
technology in the emergency setting, an assessment not completed in the
current study despite the title.
So the USCOM is comprehensively validated, while NICCOMO is a test
technology, and its disagreement with USCOM suggests further evaluation in
animals and humans, across a wide range of outputs and diseases is
required before its utilisation could be countenanced in emergency
medicine.
Comparison of method studies are technically difficult, and involve
establishing a reference standard, USCOM, and then comparing paired
measures from a proposed test technique, NICCOMO, acquired under identical
conditions. Bland-Altman comparison can only determine if the two methods
agree or disagree.(2) If the comparison demonstrates disagreement, as the
authors propose, then the appropriate scientific conclusion is that, as
the reference method has superior validation and clinical proof, the test
method doesn't agree with the reference method "in our hands", and is
therefore not valid. However additional studies of any new technology may
be worthwhile if a suspicion of occult potential clinical utility
persists.
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As authors of a previous report about serious injuries that occurred during an extreme sports obstacle course in the U.S. (1), we read with interest the article by Alana Hawley, etal describing injury and illness outcomes in a series of Canadian obstacle course events. (2) In this Canadian study a small percentage of participants presented to onsite medial services; the majority of complaints were minor and musculoskele...
Many thanks for your interest in our study.
We agree that as a retrospective study that compares head injured patients presenting within and after 24 hours of injury that have undergone CT imaging our study does have limitations. However, there are currently few data to guide clinicians in this area. We found only 2 other retrospective cohort studies and an abstract that assessed such patients in a recently pu...
I thank the authors for highlighting an ongoing concern I have with NICE head injury guidance - namely that the guidance is based on studies of acute head injuries presenting soon after injury and doesn't take delayed presentations into account. However my concern would be the reverse of their own as I feel if we adhered to NICE guidance in patients presenting after 24 hours we would be performing large numbers of unnece...
Pocock et al present fascinating insight to the challenges of the pre -hospital environment for undertaking clinical trials (Human factors in pre hospital research: lessons from the PARAMEDIC trial Pocock H, et al, Emerg Med J 2016; 33: 562-568) which explain the lack of clear strategies of the implementation of research protocol on this issue. The need for strong relationships between teams brings into focus the potenti...
The comprehensive review by Ramlakhan et al of the effectiveness of primary care services located within EDs draws mixed conclusions. Whilst initial efficiency savings were identified (both in terms of GP resource utilisation and overall cost) and subsequent hospital admission and referrals appeared reduced, other outcomes proved disappointing or at best equivocal including length of stay, waiting time and patient satisfa...
I read with interest your recent case report of a perilunate dislocation. This case highlights the importance of careful assessment of often complex wrist X-rays. As a small point, I would however disagree that the 'spilled teacup sign' is a sign of a perilunate dislocation. This sign is a radiological sign of a lunate rather than perilunate dislocation. The key to distinguishing between between both is to first determine...
Murphy-Jones and Timmons described paramedics' experiences of end-of- life decision making with regard to nursing home residents, including the challenges faced by paramedics when patients lacked decision making capacity and the resultant stress from uncertainty about appropriate treatments. [1] Among the solutions suggested, an essential, straightforward and well-tested tool for the perplexed paramedic was not available...
We have read with great interest the review of Ramlakhan et al. (2016)1 on the effectiveness of co-locating emergency departments (ED) and primary care centres and the findings of the authors that the evidence is inconclusive. Yet, we are confident that there are more hints and clues in the available evidence for policy guidance than was done in the paper by Ramlakhan et al. (2016). We will illustrate this with a recent po...
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This comparison of non-invasive haemodynamic devices, although valuable, demonstrates some methodological aspects of the Bland-Altman method that should be considered to ensure the accuracy of any proposed conclusions.
The statistical minimum for comparison of two medical device measurement methods includes reporting mean ?SD values for both methods, correlation, and Bland-Altman bias and precision, mean % diff...
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