Foreword
Westmead Emergency
Research Unit
Editor
Amith Shetty
This month we are pleased to announce the creation of the Vicky Chaplin
nursing research grant funded by our emergency department trust fund
and research unit. This will be a bi-annual $500 grant which can be used to
pay for nursing research related activities in the department. Eligibility and
selection criteria will be soon worked upon and posted on the ED intranet
site.
Contributors
Margaret Murphy
Naren Gunja
Gopi Mann
Toby Thomas
In this month’s edition –
DUBIUS - Questionable tests
and procedures – P 3
NOSTOS ALGOS - Blast from
the past – Experiments on the
Transfusion of Blood by the
Syringe P4
This edition we launch our telescope into the blog world through the
trained eyes of our resident Druid Toby Thomas! BIN REIECTIS. Here Tobs
will present to you a glimpse into the hot springs from the blog world. Feel
welcome to make contributions.
So what is Nostos Algos? Each month we feature a ground-breaking (or
maybe not) article from the past – the aim is not only to shed light on the
history of our practice of medicine but also to generate a inquisitorial
attitude for us when we go about conducting our daily medical activities.
Hopefully, one of our many unanswered queries will lead to a groundbreaking intervention!
Feel free to send your articles, topics or suggestions to
samit36@hotmail.com or Jennifer.Johnson@swahs.health.nsw.gov.au or
margaret.murphy@swahs.health.nsw.gov.au
DISPUTATIO – aggie baggie –
EMR boom or bust or just
another gen-Y myth – P5-8
PRIMUS – RECAP multicentre
trials at WMH ED - P9
BIN REIECTIS – Blog recap –
P10
PRÉCIS MENSTRUA May 2013
– P11 – P19
CONCLUSIO – Journal club
articles and department
publications – P20.
Instigo Cogito Novo Amplio
Page 1
This month’s research highlights include the Cochrane review article on the use of corticosteroids in
meningitis – which reinstates the past data – steroids reduce risk of development of neurologic
complications without any significant impact on mortality.
An interesting article with contributors from Westmead has noted about the role of aggressive BP
lowering in patient with acute ICH without adverse outcomes for patients but the outcome is been
debated in literary circles and expect some more trial like these before any change in clinical
management to occur.
A recent JAMA pediatrics articles puts into numbers the NNT for radiation induced solid organ
tumours for children. Radiation is soon becoming the next generation Thalidomide. Unfortunately a
lot amongst us (medical profession) will never agree with the findings until a law suit confirms it.
And thus continues the ordering of PAN-scans and chest and abdomen scans to diagnose nonsignificant d-dimer results and mild cases of appendicitis. (Yes, my glass is usually half-empty).
A newly released AMPLIFY trial results on Apixaban, an oral factor Xa inhibitor suggests it to be as
effective as warfarin in management of VTE with reduced risk of bleeding events. Are the days of
warfarin numbered? I am sure we will not give up without a fight! Maybe an off-patent non-financed
drug trial may convince us.
An article highlights the use of Capnography in the diagnosis of DKA – but again I fail to see a realtime application for this in diagnosis of DKA but may make a good study for further research into use
of Capnography for ongoing monitoring for progress of DKA.
There has been a recent surge in evidence suggesting increased risk of development of NIDDM in
patients receiving statins – in this issue we highlight of these articles. But whether there is a causal
role for statins or whether patients on statins belong to the high risk group with metabolic
dysfunction needs to be fully answered.
A great article on outcomes of patients receiving therapeutic hypothermia after cardiac arrest and
undergoing PTCA has shown ongoing evidence for its role in management of patients with cardiac
arrest and ROSC. Our feature articles this month reflect on caloric predictions and Blaming men for
everything wrong! (Remember some humour is good even for doctors)
This month we did not receive any updates on the ED or toxicology journal clubs – hopefully these
will be back next month.
Instigo Cogito Novo Amplio
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DUBIUS





Don’t perform imaging of the carotid arteries for simple syncope without other neurologic
symptoms. Occlusive carotid artery disease does not cause fainting but rather causes focal
neurologic deficits such as unilateral weakness. Thus, carotid imaging will not identify the
cause of the fainting and increases cost. Fainting is a frequent complaint, affecting 40% of
people during their lifetime.
Don’t use opioid treatment for migraine except as a last resort. Opioid treatment for
migraine should be avoided because more effective, migraine-specific treatments are
available. Frequent use of opioid treatment can worsen headaches. Opioids should be
reserved for those with medical conditions precluding the use of migraine-specific
treatments or for those who fail these treatments.
Cough and cold medicines should not be prescribed or recommended for respiratory
illnesses in children under four years of age. Research has shown these products offer little
benefit to young children and can have potentially serious side effects. Many cough and cold
products for children have more than one ingredient, increasing the chance of accidental
overdose if combined with another product.
In the evaluation of simple syncope and a normal neurological examination, don’t obtain
brain imaging studies (CT or MRI). In patients with witnessed syncope but with no
suggestion of seizure and no report of other neurologic symptoms or signs, the likelihood of
a central nervous system (CNS) cause of the event is extremely low and patient outcomes
are not improved with brain imaging studies.
Avoid admission or preoperative chest x-rays for ambulatory patients with unremarkable
history and physical exam. Performing routine admission or preoperative chest x-rays is not
recommended for ambulatory patients without specific reasons suggested by the history
and/or physical examination findings. Only 2% of such images lead to a change in
management. Obtaining a chest radiograph is reasonable if acute cardiopulmonary disease is
suspected or there is a history of chronic stable cardiopulmonary disease in a patient older
than age 70 who has not had chest radiography within six months. 1
1
Adapted from Choosing wisely.org an initiative of American Board of Internal Medicine and involving relevant
other medical specialty groups
Instigo Cogito Novo Amplio
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NOSTOS ALGOS - Blast from the past
In this edition I present to you the first few pages of Dr James Blundell’s presentation on successful
dog to dog blood transfusion – brutal as it may read – I believe that medicine today is a product of
the endeavours of these few thoughtful questioning minds!
Med Chir Trans. 1818; 9(Pt 1): 56–92.
Experiments on the Transfusion of Blood by the Syringe
James Blundell
A FEW months ago I was requested to visit a woman who was sinking under uterine hemorrhagy.
The discharge had stopped before my arrival, but her fate was decided, and notwithstanding every
exertion of the medical attendants, she died in the course of two hours. Reflecting afterwards on
this melancholy scene, for there were circumstances which gave it a peculiar interest, I could not
forbear considering, that the patient might very probably have been saved by transfusion; and that,
although there was little opportunity for operating in the usual manner, the vessels might have been
replenished by means of the syringe with facility and promptitude. As it seemed doubtful, however,
whether the blood would remain fit for the animal functions after its passage through the
instrument, the following experiments were instituted with a view to ascertain the point; and they
are now submitted, with all their imperfections, to the consideration of the Society, under the hope,
that they may contribute a little to excite the attention of the medical philosopher, and recommend
a neglected operation to the experimental investigation which it seems to deserve.
The femoral vessels of the dog were laid bare at the groin; and a pipe, sufficiently large to fill the
artery, was introduced with its extremity toward the heart. On removing the ligature, which had
been thrown around the vessel to prevent a premature discharge, the blood rushed out with such
impetuosity, that eight ounces escaped in the course of two minutes, and the discharge soon
afterwards ceased. From this discharge of blood, the most alarming symptoms arose; distress and
gasping, struggling and convulsions, and at length a profound fainting, marked by stoppage of the
circulation, by insensibility, and by a complete relaxation of the abdominal muscles.
In this condition the animal was suffered to lie for a few seconds, when six ounces of blood taken
from the artery of another dog, were injected into the femoral vein, in a manner which will be
hereafter described. In consequence of this operation, it soon revived; the abdominal muscles
became firm, and the respiration regular, sensibility was restored, and the blood again circulated,
indeed so briskly, that it pushed away the concretion which had formed in the femoral tube, and
rushed out. So sudden and complete was the resuscitation, that the animal seemed rather to awake
from sleep, than arise from apparent death.
To give this experiment (which will be found in the annexed register, together with various
repetitions,) all its force, it may be proper to observe, that the combination of symptoms just
enumerated is mortal, and that whatever the symptoms be, the dog invariably dies, when left to its
natural resources, if the blood is suffered, as in this instance, to flow from the femoral tube, until the
discharge spontaneously ceases. Transfusion alone can save it. From facts like these it is evident,
that the transmission of blood through the syringe, does not unfit it for the animal purposes; but as
is a principle, which lies at the bottom of the whole operation, it may be proper to confirm it by the
following experiments.
Instigo Cogito Novo Amplio
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DISPUTATIO
EMR (electronic medical records) – boom or bust or just another
gen-Y myth!
We all know this is the future and yet we hold out – is this just a personal choice or is it because
there is no evidence yet to prove the benefits of embracing technology. While increasing numbers of
hospitals world-wide continue to implement EMR successfully without the doomsday scenario that
could occur once a year of hardware failure! We wonder if these hospitals have 1:1 medical
personnel to hardware ratios as this is almost always cited as an impediment to successful EMR
installation.
In the next few pages, I try and examine a few papers on this topic. Unfortunately I may be a bit
biased here as though I belong in the gen-X category (or even older) I do believe that may be EMR is
not all that bad, if embraced fully and implemented with specific back up strategies.
Journal of Medical Systems. 36(6):3795-803, 2012 Dec.
Using electronic medical record systems for admission decisions in emergency departments:
examining the crowdedness effect.
Ben-Assuli O, Leshno M et al
This study evaluated the contribution of an EMR IS to physicians by investigating whether EMR IS
leads to improved medical outcomes in points of care in EDs under different levels of crowdedness.
For this purpose a track log-file analysis of a database containing 3.2 million ED referrals in seven
main hospitals in Israel (the whole population in these hospitals) was conducted. The findings
suggest that viewing medical history via the EMR IS leads to better admission decisions, and
reduces the number of possibly avoidable single-day admissions. Furthermore, although the ED
can be very stressful especially on crowded days, physicians used EMR IS more on crowded days
than on non-crowded days. These results have implications as regards the viability of EMR IS in
complex, fast-paced environments.
Modern Healthcare 42.45 (Nov 5, 2012): 10.
Backup plan: Despite outages, EHRs prove their worth
Conn, Joseph.
Abstract (summary)
In New York City, where several hospitals were evacuated due to power outages and flooding, New
York's state-wide health information exchange ran without a flicker, fulfilling the promise of
health information technology brought into focus by Hurricane Katrina, which devastated Gulf
Coast healthcare organizations in 2005. Meanwhile, in Pittsburgh, some 350 miles from the south
New Jersey seashore where super storm Sandy made landfall, remote-hosted EHRs used by the 479bed Western Pennsylvania Hospital and 397-bed Allegheny General Hospital went dark, roughly
between 8 p.m. Monday and 4 a.m. Tuesday. Several dozen more hospital EHRs were similarly
affected as Sandy knocked out an all scripts data center in Mountain Lakes, N.J., about 30 miles
northwest of New York City. The state-wide New York eHealth Collaborative health information
exchange stores partial copies of member hospitals' patient medical records on its own servers and
has a fully redundant data center in Texas.
American Journal of Emergency Medicine. 30(7):1235-40, 2012 Sep.
Instigo Cogito Novo Amplio
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First medical contact and physicians' opinion after the implementation of an electronic record
system.
Claret PG. Sebbanne M et al.
Abstract
Hospitals implement electronic medical record systems (EMRSs) that are intended to support
medical and nursing staff in their daily work. Evolution toward more computerization seems
inescapable. Nevertheless, this evolution introduced new problems of organization. This before-andafter observational study evaluated the door-to-first-medical-contact (FMC) times before and after
the introduction of EMRS. A satisfaction questionnaire, administered after the "after" period,
measured clinicians' satisfaction concerning computerization in routine clinical use. The following 5
questions were asked: Do you spare time in your note taking with EMRS? Do you spare time in the
medical care that you provide to the patients with EMRS? Does EMRS improve the quality of
medical care for your patients? Are you satisfied with the EMRS implementation? Would you
prefer a return to handwritten records? Results showed an increase in door-to-FMC time induced
by EMRS and a lower triage capacity. In the satisfaction questionnaire, clinicians reported minimal
satisfaction but refused to return to handwritten records. The increase in door-to-FMC time may be
explained by the improved quantity/quality of data and by the many interruptions due to the
software. Medical reorganization was requested after the installation of the EMRS.
Journal of the American Medical Informatics Association. 19(3):334-40, 2012 May-Jun.
The impact of electronic health records on care of heart failure patients in the emergency room.
Connelly DP, Park YT et al
We conducted a retrospective study of 5166 adults with heart failure in three metropolitan EDs.
RESULTS: At two EDs internals (patients with EHR) had lower odds of mortality if hospitalized (OR
0.55; 95% CI 0.38 to 0.81 and 0.45; 0.21 to 0.96), fewer laboratory tests during the ED visit (-4.6%; 8.9% to -0.1% and -14.0%; -19.5% to -8.1%) as well as fewer medications (-33.6%; -38.4% to -28.4%
and -21.3%; -33.2% to -7.3%). At one of these two EDs, internals had lower odds of hospitalization
(0.37; 0.22 to 0.60). At the third ED, internal patients only experienced a prolonged ED LOS (32.3%;
6.3% to 64.8%) but no other differences. There was no association with hospital LOS or number of
procedures ordered. DISCUSSION: EHR availability was associated with salutary outcomes in two of
three ED settings and prolongation of ED LOS at a third, but evidence was mixed and causality
remains to be determined. CONCLUSIONS: An EHR may have the potential to be a valuable adjunct
in the care of heart failure patients.
Journal of the American Medical Informatics Association. 19(3):443-7, 2012 May-Jun.
Impact of electronic health record implementation on patient flow metrics in a
pediatric emergency department.
Spellman Kennebeck S, Timm N et al
Implementing electronic health records (EHR) in healthcare settings incurs challenges, none more
important than maintaining efficiency and safety during rollout. This report quantifies the impact of
offloading low-acuity visits to an alternative care site from the emergency department (ED) during
EHR implementation. In addition, the report evaluated the effect of EHR implementation on overall
patient length of stay (LOS), time to medical provider, and provider productivity during
implementation of the EHR. Overall LOS and time to doctor increased during EHR implementation.
On average, admitted patients' LOS was 6-20% longer. For discharged patients, LOS was 12-22%
longer. Attempts to reduce patient volumes by diverting patients to another clinic were not
effective in minimizing delays in care during this EHR implementation. Delays in ED throughput
during EHR implementation are real and significant despite additional providers in the ED, and in
this setting resolved by 3 months post-implementation.
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Academic Emergency Medicine. 19(2):217-27, 2012 Feb.
Electronic versus manual data processing: evaluating the use of electronic health records in out-ofhospital clinical research.
Newgard CD. Zive D et al.
RESULTS: During the 21-month period, 418 patients underwent both data processing methods and
formed the primary cohort. Agreement was good to excellent (kappa = 0.76 to 0.97; intraclass
correlation coefficient [ICC] = 0.49 to 0.97), with exact agreement in 67% to 99% of cases and a
median difference of zero for all continuous and ordinal variables. The proportions of missing out-ofhospital values were similar between the two approaches, although electronic processing generated
more missing outcomes (87 of 418, 21%, 95% confidence interval [CI] = 17% to 25%) than the
manual approach (11 of 418, 3%, 95% CI = 1% to 5%). Case ascertainment of eligible injured patients
was greater using electronic methods (n = 3,008) compared to manual methods (n = 629).
CONCLUSIONS: In this sample of out-of-hospital trauma patients, an all-electronic data processing
strategy identified more patients and generated values with good agreement and validity
compared to traditional data collection and processing methods.
Academic Emergency Medicine. 17(8):824-33, 2010 Aug.
Efficiency and economic benefits of a payer-based electronic health record in an
emergency department.
Daniel GW, Ewen E et al.
OBJECTIVES: The objective was to evaluate the use of a payer-based electronic health record (PEHR), which is a clinical summary of a patient's medical and pharmacy claims history, in
an emergency department (ED) on length of stay (LOS) and plan payments.
Encounters with P-EHR use (n = 779) were identified between September 1, 2005, and February 17,
2006; encounters from the same health plan (n = 1,509) between November 1, 2004, and March 31,
2005, were compared. Outcomes were ED LOS and plan payment for the ED encounter. Analyses
evaluated the effect of using the P-EHR in the ED setting on study outcomes using multivariate
regressions and the nonparametric bootstrap. RESULTS: After covariate adjustment, among visits
resulting in discharge (ED-only), P-EHR visits were 19 minutes shorter (95% confidence interval [CI]
= 5 to 33 minutes) than non-P-EHR visits. Among visits resulting in hospitalization, the P-EHR was
associated with an average 77-minute shorter ED LOS (95% CI = 28 to 126 minutes), compared to
non-P-EHR visits. The P-EHR was associated with an average of $1,560 (95% CI = $43 to $2,910)
lower total plan expenditures for hospitalized visits. No significant difference in total payments was
observed among discharged visits. CONCLUSIONS: In the study ED, the P-EHR was associated with a
significant reduction in ED LOS overall and was associated with lower plan payments for visits that
resulted in hospitalization.
AMII - Annual Symposium Proceedings/AMIA Symposium. 2009:634-8, 2009.
Impact of prior clinical information in an EHR on care outcomes of emergency patients.
Theera-Ampornpunt N, Speedie SM et al.
A patient's prior clinical information available electronically can be helpful during the care process,
particularly in the emergency department (ED). The effect of such information on quality and
efficiency of ED patient care has not been adequately studied. This study uses secondary data to
investigate its impact on surrogate measures of care quality and efficiency among 6,143 congestive
heart failure, diabetic, and asthmatic patients in 3 EDs. Results show that in some subgroups of
chronic patients in some EDs, availability of prior clinical information in the electronic health
records was associated with significantly lower hospitalization rates, shorter inpatient length of
stay, and reduction in the numbers of laboratory tests and diagnostic procedures ordered during
the ED visit. However, there were also contradictory effects and lack of significance in other
subgroups. The effects vary by ED and disease, highlighting the possibility of contextual differences
influencing the effects of such clinical information.
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The Health Care Manager Issue: Volume 29(4), October/December 2010, pp 318-323
Technological Trends in Health Care: Electronic Health Record
Abraham, Sam RN, MS
Conclusion:
EMR is here, like it or not – adapt or struggle! So what does the evidence tell us? Whilst I have only
outlined a few papers here; there are some trends in evidence regarding EMR use in ED based on
many other articles accessible. Bad news first! EMR increases workload and slows EM
physicians during the initial phases of EMR implementation. First-time patients i.e.
patients with no EMR take longer to process but inpatient teams and senior medical staff
gain from the entries and access to this EMR – in decision making and improved work
transparency. Good news – EMR has definite clinical, fiscal and management benefits for
patients with recurrent ED presentations, chronic disease management.
Instigo Cogito Novo Amplio
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PRIMUS
Multicentre trials currently underway at Westmead ED
Microchemirism Study – for patients who may need major transfusions after trauma
All patients meeting Trauma Category 1 criteria collect 2 tubes of
↓
Fill in the label and send to ICPMR with usual samples - no orders on Firstnet
BLISS Study – to correlate loads of bacterial DNA in blood versus outcomes in patients presenting to
ED with sepsis.
All patients meeting Triage category 2 for SEPSIS collect 1 tube of
↓
Order Bacterial load test on power orders and send sample with all the blood samples to ICPMR - PAXGENE sticker
Instigo Cogito Novo Amplio
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BIN REIECTIS
Michelle Lin: Academic Emergency Medicine
http://academiclifeinem.com/rush-protocol-rapid-ultrasound-for-shock-and-hypotension/
This blog is worth visiting just for the PV cards (mind out of the gutter people – its short for “Paucis
Verbis” or “in a few words”) These 1 page PDF’s summarize a huge range of topics and are useful
both on the floor and for fellowship revision.
The recent post is a well written and practical summary of the RUSH Protocol for the assessment and
management of hypotension.
EM Lyceum
http://emlyceum.com/
Each month this site publishes a series of questions which they hope will stimulate debate /
discussion amongst ED practitioners. They then review the literature and publish what they believe
to be evidenced based answers. In the past they have covered burns management, troponin, sepsis,
PE etc etc.
This month they are reviewing fluid responsiveness which seems to be a hot topic in “the blogs” at
the moment
Emergency Literature of Note
http://www.emlitofnote.com/2013/04/new-south-wales-dislikes-cerner.html
Ryan Radecki describes his site as a “poor man’s Journal Watch”. It would be more accurate to say it
is Journal Watch without any conflict of interest or drug-company whores.
He has a scathing review of the recent paper out of Nepean about electronic medical records
Amal Mattu: Case of The Week
http://ekgumem.tumblr.com/
Each week Amal Mattu posts a short (usually about 10 minutes) video on an ECG topic relevant to
Emergency Medicine. Topics covered so far include Wellens Syndrome, Sgarbossa Criteria, RV AMI,
Posterior Wall AMI, subtle signs of electrolyte abnormalities, de Winter T Waves, WCT, NCT and
more. The presentations provide information that (as Mel Herbert would say) you can use on the
floor during your next shift
The Trauma Professional’s Blog
http://regionstraumapro.com/
Michael MacGonigal is a trauma surgeon from Regions Hospital in the USA. He started a blog
because he kept getting asked the same questions by each generation of trainees. His most recent
post is about the value of protocols in trauma. His previous posts about the management of
pneumothorax in trauma patients (does oxygen alone really work; does an occulot PTX in a
ventilated patient really need a chest drain) are excellent
Emergency Medicine Updates
http://emupdates.com/
Reuben Strayer is a friend of Scott Weingardt's but I won’t hold that against him. He doesn’t post
very often but when he does it is invariably worth the wait. Previous posts include management of
severe asthma, check lists for intubation and procedural sedation, a review on ketamine (he is the
man when it comes to ketamine), intubating kids for people who almost never intubate kids. His
recent post is on ectopic pregnancy in the emergency department.
As an added bonus, you can email the authors of all these sites with any question and they will
respond. Very cool!
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PRÉCIS MENSTRUA
BMJ. 2013 May 23; 346:f2610. doi: 10.1136/bmj.f2610.
Risk of incident diabetes among patients treated with statins: population based study.
Carter AA, Gomes T et al.
Abstract
OBJECTIVE:
To examine the risk of new onset diabetes among patients treated with different HMG-CoA
reductase inhibitors (statins).
DESIGN:
Population based cohort study with time to event analyses to estimate the relation between use of
particular statins and incident diabetes. Hazard ratios were calculated to determine the effect of
dose and type of statin on the risk of incident diabetes.
PARTICIPANTS:
All patients aged 66 or older without diabetes that started treatment with statins from 1 August
1997 to 31 March 2010. The analysis was restricted to new users who had not been prescribed a
statin in at least the preceding year. Patients with established diabetes before the start of treatment
were excluded.
RESULTS:
Compared with pravastatin (the reference drug in all analyses), there was an increased risk of
incident diabetes with atorvastatin (adjusted hazard ratio 1.22, 95% confidence interval 1.15 to
1.29), rosuvastatin (1.18, 1.10 to 1.26), and simvastatin (1.10, 1.04 to 1.17). There was no
significantly increased risk among people who received fluvastatin (0.95, 0.81 to 1.11) or lovastatin
(0.99, 0.86 to 1.14). The absolute risk for incident diabetes was about 31 and 34 events per 1000
person years for atorvastatin and rosuvastatin, respectively. There was a slightly lower absolute risk
with simvastatin (26 outcomes per 1000 person years) compared with pravastatin (23 outcomes per
1000 person years). Our findings were consistent regardless of whether statins were used for
primary or secondary prevention of cardiovascular disease. Although similar results were observed
when statins were grouped by potency, the risk of incident diabetes associated with use of
rosuvastatin became non-significant (adjusted hazard ratio 1.01, 0.94 to 1.09) when dose was taken
into account.
CONCLUSIONS:
Compared with pravastatin, treatment with higher potency statins, especially atorvastatin and
simvastatin, might be associated with an increased risk of new onset diabetes.
Cochrane Acute Respiratory Infections Group Published Online: 4 JUN 2013
Corticosteroids for acute bacterial meningitis
Brouwer MC, McIntyre P et al
Background
In experimental studies, the outcome of bacterial meningitis has been related to the severity of
inflammation in the subarachnoid space. Corticosteroids reduce this inflammatory response.
Objectives
To examine the effect of adjuvant corticosteroid therapy versus placebo on mortality, hearing loss
and neurological sequelae in people of all ages with acute bacterial meningitis.
Main results
Twenty-five studies involving 4121 participants were included. Corticosteroids were associated with
a non-significant reduction in mortality (17.8% versus 19.9%; risk ratio (RR) 0.90, 95% confidence
interval (CI) 0.80 to 1.01, P = 0.07). A similar non-significant reduction in mortality was observed in
adults receiving corticosteroids (RR 0.74, 95% CI 0.53 to 1.05, P = 0.09). Corticosteroids were
associated with lower rates of severe hearing loss (RR 0.67, 95% CI 0.51 to 0.88), any hearing loss (RR
0.74, 95% CI 0.63 to 0.87) and neurological sequelae (RR 0.83, 95% CI 0.69 to 1.00).
Instigo Cogito Novo Amplio
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Subgroup analyses for causative organisms showed that corticosteroids reduced mortality
in Streptococcus pneumoniae (S. pneumoniae) meningitis (RR 0.84, 95% CI 0.72 to 0.98), but not
in Haemophilus influenzae (H. influenzae) or Neisseria meningitidis (N. meningitidis) meningitis.
Corticosteroids reduced severe hearing loss in children with H. influenzae meningitis (RR 0.34, 95%
CI 0.20 to 0.59) but not in children with meningitis due to non-Haemophilus species.
In high-income countries, corticosteroids reduced severe hearing loss (RR 0.51, 95% CI 0.35 to 0.73),
any hearing loss (RR 0.58, 95% CI 0.45 to 0.73) and short-term neurological sequelae (RR 0.64, 95%
CI 0.48 to 0.85). There was no beneficial effect of corticosteroid therapy in low-income countries.
Subgroup analysis for study quality showed no effect of corticosteroids on severe hearing loss in
high-quality studies.
Corticosteroid treatment was associated with an increase in recurrent fever (RR 1.27, 95% CI 1.09 to
1.47), but not with other adverse events.
Authors' conclusions
Corticosteroids significantly reduced hearing loss and neurological sequelae, but did not reduce
overall mortality. Data support the use of corticosteroids in patients with bacterial meningitis in
high-income countries. We found no beneficial effect in low-income countries.
Ann Intern Med. 2013 Jun 4; 158(11):800-6. doi: 10.7326/0003-4819-158-11-201306040-00004.
Aspirin versus low-molecular-weight heparin for extended venous thromboembolism prophylaxis
after total hip arthroplasty: a randomized trial.
Anderson DR, Dunbar MJ et al.
BACKGROUND:
The role of aspirin in thromboprophylaxis after total hip arthroplasty (THA) is controversial.
DESIGN:
Multicenter randomized, controlled trial with a noninferiority design based on a minimal clinically
important difference of 2.0%. Randomization was electronically generated; patients were assigned
to a treatment group through a Web-based program. Patients, physicians, study coordinators, health
care team members, outcome adjudicators, and data analysts were blinded to interventions.
(Current Controlled Trials: ISRCTN11902170)
INTERVENTION:
After an initial 10 days of dalteparin prophylaxis after elective THA, patients were randomly assigned
to 28 days of dalteparin (n = 400) or aspirin (n = 386).
MEASUREMENTS:
Symptomatic VTE confirmed by objective testing (primary efficacy outcome) and bleeding.
RESULTS:
Five of 398 patients (1.3%) randomly assigned to dalteparin and 1 of 380 (0.3%) randomly assigned
to aspirin had VTE (absolute difference, 1.0 percentage point [95% CI, -0.5 to 2.5 percentage
points]). Aspirin was noninferior (P < 0.001) but not superior (P = 0.22) to dalteparin. Clinically
significant bleeding occurred in 5 patients (1.3%) receiving dalteparin and 2 (0.5%) receiving aspirin.
The absolute between-group difference in a composite of all VTE and clinically significant bleeding
events was 1.7 percentage points (CI, -0.3 to 3.8 percentage points; P = 0.091) in favor of aspirin.
LIMITATION:
The study was halted prematurely because of difficulty with patient recruitment.
CONCLUSION:
Extended prophylaxis for 28 days with aspirin was noninferior to and as safe as dalteparin for the
prevention of VTE after THA in patients who initially received dalteparin for 10 days. Given its low
cost and greater convenience, aspirin may be considered a reasonable alternative for extended
thromboprophylaxis after THA.
Blood. 2013 May 9; 121(19):3953-61. doi: 10.1182/blood-2012-11-469551. Epub 2013 Apr 2.
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Risk factors for first venous thromboembolism around pregnancy: a population-based cohort
study from the United Kingdom.
Sultan AA, Tata LJ et al.
Abstract
Knowledge of the absolute risk (AR) for venous thromboembolism (VTE) in women around
pregnancy and how potential risk factors modify this risk is crucial in identifying women who would
benefit most from thromboprophylaxis. We examined a large primary care database containing
376 154 pregnancies ending in live birth or stillbirth from women aged 15 to 44 years between 1995
and 2009 and assessed the effect of risk factors on the incidence of antepartum and postpartum VTE
in terms of ARs and incidence rate ratios (IRR), using Poisson regression. During antepartum,
varicose veins, inflammatory bowel disease (IBD), urinary tract infection, and pre-existing diabetes
were associated with an increased risk for VTE (ARs, ≥139/100 000 person-years; IRRs, ≥1.8/100 000
person-years). Postpartum, the strongest risk factor was stillbirth (AR, 2444/100 000 person-years;
IRR, 6.2/100 000 person-years), followed by medical comorbidities (including varicose veins, IBD, or
cardiac disease), a body mass index (BMI) of 30 kg/m (2) or higher, obstetric hemorrhage, preterm
delivery, and caesarean section (ARs, ≥637/100 000 person-years; IRRs, ≥1.9/100 000 person-years).
Our findings suggest that VTE risk varies modestly by recognized factors during antepartum;
however, women with stillbirths, preterm births, obstetric hemorrhage, caesarean section delivery,
medical comorbidities, or a BMI of 30 kg/m(2) or higher are at much higher risk for VTE after
delivery. These risk factors should receive careful consideration when assessing the potential need
for thromboprophylaxis during the postpartum period.
Hypertension. 2013; 61: 1309-1315 Published online before print March 25, 2013, doi: 10.1161/
Blood Pressure Lowering and Cerebral Blood Flow - Intensive Blood Pressure Lowering Increases
Cerebral Blood Flow in Older Subjects With Hypertension
Tryambake D, Jiabao He et al.
Abstract
Hypertension is associated with reduced cerebral blood flow (CBF). Intensive (<130/80 mm Hg)
blood pressure (BP) lowering in older people might give greater reduction in cardiovascular risk,
but there are concerns that this might produce hypoperfusion which may precipitate falls and
possibly stroke. We determined the effect of intensive compared with usual BP lowering on CBF in
hypertensive older subjects. Individuals aged >70 years with a history of systolic hypertension on 1
or no BP lowering drugs were recruited from primary care (n=37; age, 75±4 years; systolic BP, >150
mm Hg) and randomized to receive intensive (target BP, <130/80 mm Hg) or usual (target BP,
<140/85 mm Hg) BP lowering for 12 weeks, with reviews every 2 weeks. CBF, determined using 3T
arterial spin labeling MRI, and 24-hour ambulatory BP were performed at baseline and after 12
weeks of treatment. Baseline BP (ambulatory or in clinic) and baseline gray matter CBF were not
significantly different between the groups. After treatment, BP was reduced significantly in both
groups but fell more in the intensive group (26/17 versus 15/5 mm Hg; P<0.01). Over the same
period, gray matter CBF increased significantly in the intensive group (7±11 mL/min per 100 g;
P=0.013) but was unchanged in the usual BP target group (−3±9 mL/min per 100 g; P=0.23); P<0.01
for comparison. Intensive BP lowering in older people with hypertension increases CBF, compared
with BP lowering to usual target. These findings suggest hypertension in older people shifts the
autoregulatory CBF curve rightward and downward and is reversible with BP lowering.
Western Journal of Emergency Medicine, Articles In Press
Predictive Value of Capnography for Diagnosis in Patients with Suspected Diabetic Ketoacidosis in
the Emergency Department
Soleimanpour H, Taghizadieh A et al.
Introduction: Metabolic acidosis confirmed by arterial blood gas (ABG) analysis is one of the
diagnostic criteria for diabetic ketoacidosis (DKA). Given the direct relationship between end-tidal
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carbon dioxide (ETco2), arterial carbon dioxide (PaCO2) and metabolic acidosis, measuring ETco2 may
serve as a surrogate for ABG in the assessment of possible DKA. The current study focuses on the
predictive value of capnography in diagnosing DKA in patients referring to the emergency
department (ED) with increased blood sugar levels and probable diagnosis of DKA.
Methods: In a cross-sectional prospective descriptive-analytic study carried out in an ED, we studied
181 patients older than 18 years old with blood sugar levels of higher than 250 mg/dl and probable
DKA. ABG and capnography were obtained from all patients. To determine predictive value,
sensitivity, specificity and cut-off points, we developed receiver operating characteristic curves.
Results: Sixty-two of 181 patients suffered from DKA. We observed significant differences between
both groups (DKA and non-DKA) regarding age, pH, blood bicarbonate, PaCO2 and ETco2 values
(P≤0.001). Finally, capnography values more than 24.5 mmHg could rule out the DKA diagnosis with
a sensitivity and specificity of 0.90.
Conclusion: Capnography values greater than 24.5 mmHg accurately allow the exclusion of DKA in
ED patients suspected of that diagnosis. Capnography levels lower that 24.5 mmHg were unable to
differentiate between DKA and other disease entities. [West J Emerg Med.]
Resuscitation - 05 June 2013 (10.1016/j.resuscitation.2013.05.022)
Prophylactic lidocaine for post resuscitation care of patients with out-of-hospital ventricular
fibrillation cardiac arrest
Kudenchuk PJ, Newell C
Background
Antiarrhythmic drugs like lidocaine are usually given to promote return of spontaneous circulation
(ROSC) during ongoing out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation/tachycardia
(VF/VT). Whether administering such drugs prophylactically for post-resuscitation care after ROSC
prevents re-arrest and improves outcome is unstudied.
Methods
We evaluated a cohort of 1721 patients with witnessed VF/VT OHCA who did (1296) or did not
receive prophylactic lidocaine (425) at first ROSC. Study endpoints included re-arrest, hospital
admission and survival.
Results
Prophylactic lidocaine recipients and non-recipients were comparable, except for shorter time to
first ROSC and higher systolic blood pressure at ROSC in those receiving lidocaine. After initial ROSC,
arrest from VF/VT recurred in 16.7% and from non-shockable arrhythmias in 3.2% of prophylactic
lidocaine recipients, 93.5% of whom were admitted to hospital and 62.4% discharged alive, as
compared with 37.4%, 7.8%, 84.9% and 44.5%, of corresponding non-recipients (all p < 0.0001).
Adjusted for pertinent covariates, prophylactic lidocaine was independently associated with reduced
odds of re-arrest from VF/VT, odds ratio, (95% confidence interval) 0.34 (0.26–0.44) and from
nonshockable arrhythmias (0.47 (0.29–0.78)); a higher hospital admission rate (1.88, (1.28–2.76))
and improved survival to discharge (1.49 (1.15–1.95)). However in a propensity score-matched
sensitivity analysis, lidocaine's only beneficial association with outcome was in a lower incidence of
recurrent VF/VT arrest.
Conclusions
Administration of prophylactic lidocaine upon ROSC after OHCA was consistently associated with
less recurrent VF/VT arrest, and therapeutic equipoise for other measures. The prospect of a
promising association between lidocaine prophylaxis and outcome, without evidence of harm,
warrants further investigation.
N Engl J Med 2013; 368:2286-2293June 13, 2013DOI: 10.1056/NEJMoa1301839
Racemic Adrenaline and Inhalation Strategies in Acute Bronchiolitis
Skjerven HO, Gjengstø Hunderi JO et al.
RESULTS
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The mean age of the 404 infants included in the study was 4.2 months, and 59.4% were boys. Length
of stay, use of oxygen supplementation, nasogastric-tube feeding, ventilatory support, and relative
improvement in the clinical score from baseline (preinhalation) were similar in the infants treated
with inhaled racemic adrenaline and those treated with inhaled saline (P>0.1 for all comparisons).
On-demand inhalation, as compared with fixed-schedule inhalation, was associated with a
significantly shorter estimated mean length of stay — 47.6 hours (95% confidence interval [CI], 30.6
to 64.6) versus 61.3 hours (95% CI, 45.4 to 77.2; P=0.01) — as well as less use of oxygen
supplementation (in 38.3% of infants vs. 48.7%, P=0.04), less use of ventilatory support (in 4.0% vs.
10.8%, P=0.01), and fewer inhalation treatments (12.0 vs. 17.0, P<0.001).
CONCLUSIONS
In the treatment of acute bronchiolitis in infants, inhaled racemic adrenaline is not more effective
than inhaled saline. However, the strategy of inhalation on demand appears to be superior to that
of inhalation on a fixed schedule.
BMJ. 2013 Apr 30; 346:f2450. doi: 10.1136/bmj.f2450.
Use of serum C reactive protein and procalcitonin concentrations in addition to symptoms and
signs to predict pneumonia in patients presenting to primary care with acute cough: diagnostic
study.
van Vugt SF, Broekhuizen BD et al.
DESIGN:
Diagnostic study performed between 2007 and 2010. Participants had their history taken,
underwent physical examination and measurement of C reactive protein (CRP) and procalcitonin in
venous blood on the day they first consulted, and underwent chest radiography within seven days.
CONCLUSIONS:
A clinical rule based on symptoms and signs to predict pneumonia in patients presenting to primary
care with acute cough performed best in patients with mild or severe clinical presentation. Addition
of CRP concentration at the optimal cut off of >30 mg/L improved diagnostic information, but
measurement of procalcitonin concentration did not add clinically relevant information in this
group.
Med J Aust 2013; 198 (11): 612-615. doi: 10.5694/mja12.11754
Quantifying the proportion of general practice and low-acuity patients in the emergency
department
Nagree Y, Camarda VJ et al.
Abstract
Objective: To accurately estimate the proportion of patients presenting to the emergency
department (ED) who may have been suitable to be seen in general practice.
Design: Using data sourced from the Emergency Department Information Systems for the calendar
years 2009 to 2011 at three major tertiary hospitals in Perth, Western Australia, we compared four
methods for calculating general practice-type patients. These were the validated Sprivulis method,
the widely used Australasian College for Emergency Medicine method, a discharge diagnosis method
developed by the Tasmanian Department of Human and Health Services, and the Australian Institute
of Health and Welfare (AIHW) method.
Main outcome measure: General practice-type patient attendances to EDs, estimated using the four
methods.
Results: All methods except the AIHW method showed that 10%–12% of patients attending tertiary
EDs in Perth may have been suitable for general practice. These attendances comprised 3%–5% of
total ED length of stay. The AIHW method produced different results (general practice-type patients
accounted for about 25% of attendances, comprising 10%–11% of total ED length of stay). General
practice-type patient attendances were not evenly distributed across the week, with proportionally
more patients presenting during weekday daytime (08:00–17:00) and proportionally fewer overnight
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(00:00–08:00). This suggests that it is not a lack of general practitioners that drives patients to the
ED, as weekday working hours are the time of greatest GP availability.
Conclusion: The estimated proportion of general practice-type patients attending the EDs of
Perth’s major hospitals is 10%–12%, and this accounts for < 5% of the total ED length of stay. The
AIHW methodology overestimates the actual proportion of general practice-type patient
attendances.
J Am Geriatr Soc. 2013 May;61(5):788-92. doi: 10.1111/jgs.12203. Epub 2013 Apr 16.
Overtreatment of presumed urinary tract infection in older women presenting to the emergency
department.
Gordon LB, Waxman MJ et al.
Abstract
OBJECTIVES:
To determine how often older women presenting to an emergency department (ED) are diagnosed
with a urinary tract infection (UTI) without a positive urine culture and to investigate whether
collecting urine by catheterization instead of clean catch improves the accuracy of the urinalysis
(UA).
MEASUREMENTS:
Chief complaint, review of systems, results of UA and culture, urine procurement (clean catch,
straight catheter, or newly inserted Foley catheter), antibiotic administered or prescribed, and
diagnosis. A confirmed UTI was defined as a positive urine culture, with microbial growth of 10,000
colony-forming units (CFU)/ mL or more for clean-catch specimens and 100 CFU/mL or more for
newly inserted catheter specimens; an ED diagnosis of UTI was defined as the designation by an ED
physician.
RESULTS:
Of 153 individuals with an ED-diagnosed UTI, only 87 (57%) had confirmed UTI according to
culture. Of the remaining 66 with negative cultures, 63 (95%) were administered or prescribed
antibiotics in the ED. The method of urine procurement affected the ability of a UA to predict the
culture result (P = .02), with catheterization yielding a lower proportion of false-positive UA (31%)
than clean catch (48%).
CONCLUSION:
Nearly half of older women diagnosed with a UTI in an ED setting did not have confirmatory
findings on urine culture and were therefore inappropriately treated. Catheterization improved
the accuracy of UA when assessing older women for possible UTI.
JAMA Pediatr. 2013;():1-8. doi:10.1001/jamapediatrics.2013.311.
The Use of Computed Tomography in Pediatrics and the Associated Radiation Exposure and
Estimated Cancer Risk
Miglioretti DL, Johnson E et al
Results The use of CT doubled for children younger than 5 years of age and tripled for children 5 to
14 years of age between 1996 and 2005, remained stable between 2006 and 2007, and then began
to decline. Effective doses varied from 0.03 to 69.2 mSv per scan. An effective dose of 20 mSv or
higher was delivered by 14% to 25% of abdomen/pelvis scans, 6% to 14% of spine scans, and 3% to
8% of chest scans. Projected lifetime attributable risks of solid cancer were higher for younger
patients and girls than for older patients and boys, and they were also higher for patients who
underwent CT scans of the abdomen/pelvis or spine than for patients who underwent other types of
CT scans. For girls, a radiation-induced solid cancer is projected to result from every 300 to 390
abdomen/pelvis scans, 330 to 480 chest scans, and 270 to 800 spine scans, depending on age. The
risk of leukemia was highest from head scans for children younger than 5 years of age at a rate of 1.9
cases per 10 000 CT scans. Nationally, 4 million pediatric CT scans of the head, abdomen/pelvis,
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chest, or spine performed each year are projected to cause 4870 future cancers. Reducing the
highest 25% of doses to the median might prevent 43% of these cancers.
Conclusions and Relevance The increased use of CT in pediatrics, combined with the wide variability
in radiation doses, has resulted in many children receiving a high-dose examination. Dose-reduction
strategies targeted to the highest quartile of doses could dramatically reduce the number of
radiation-induced cancers.
Clinical Cardiology Volume 36, Issue 7, pages 414–421, July 2013
Mild Therapeutic Hypothermia After Out-Of-Hospital Cardiac Arrest Complicating ST-Elevation
Myocardial Infarction: Long-term Results in Clinical Practice
Zimmermann S, Flachskampf FA et al
Methods
We analyzed 48 patients who underwent emergency coronary angiography for STEMI after
witnessed OHCA. In 24 consecutive patients, MTH was performed via intravascular cooling (CoolGard
System, 34°C maintained for 24 hours) after initialization by rapid infusion of cold saline. Clinical,
procedural, and mortality data were compared to 24 historical controls. Neurological recovery was
assessed using the Cerebral Performance Category score (CPC) at 30-day and 1-year follow-up.
Results
Median time delay until arrival of emergency medical service was 6 minutes (MTH group) vs 6.5
minutes (controls) (P = 0.16). Initial rhythm was ventricular fibrillation in 75% vs 66.7% (P = 0.75).
There were no differences regarding baseline characteristics, angiographic findings, and success of
cardiac catheterization procedures. MTH was not associated with a higher frequency of bleeding
complications or of pneumonia. Thirty-day mortality was 33.3% in both groups. One-year mortality
was 37.5% (MTH group) vs 50% (controls) (P = 0.56). At 1 year, favorable neurological outcome (CPC
≤2) was significantly more frequent in the MTH group (58.3% vs 20.8%, P = 0.017). Multivariate
analysis identified MTH as independent predictor of favorable neurological outcome (P < 0.02, odds
ratio: 12.73).
Conclusions
MTH via intravascular cooling improves neurological long-term prognosis after OHCA due to STEMI
and is safe in clinical practice.
NEJM July 1, 2013DOI: 10.1056/NEJMoa1302507
Oral Apixaban for the Treatment of Acute Venous Thromboembolism
Agnelli G, Buller HR et al for the AMPLIFY Investigators
Apixaban, an oral factor Xa inhibitor administered in fixed doses, may simplify the treatment of
venous thromboembolism. n this randomized, double-blind study, we compared apixaban (at a dose
of 10 mg twice daily for 7 days, followed by 5 mg twice daily for 6 months) with conventional
therapy (subcutaneous enoxaparin, followed by warfarin) in 5395 patients with acute venous
thromboembolism.
RESULTS
The primary efficacy outcome occurred in 59 of 2609 patients (2.3%) in the apixaban group, as
compared with 71 of 2635 (2.7%) in the conventional-therapy group (relative risk, 0.84; 95%
confidence interval [CI], 0.60 to 1.18; difference in risk [apixaban minus conventional therapy], −0.4
percentage points; 95% CI, −1.3 to 0.4). Apixaban was noninferior to conventional therapy (P<0.001)
for predefined upper limits of the 95% confidence intervals for both relative risk (<1.80) and
difference in risk (<3.5 percentage points). Major bleeding occurred in 0.6% of patients who received
apixaban and in 1.8% of those who received conventional therapy (relative risk, 0.31; 95% CI, 0.17 to
0.55; P<0.001 for superiority). The composite outcome of major bleeding and clinically relevant
nonmajor bleeding occurred in 4.3% of the patients in the apixaban group, as compared with 9.7% of
those in the conventional-therapy group (relative risk, 0.44; 95% CI, 0.36 to 0.55; P<0.001). Rates of
other adverse events were similar in the two groups.
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CONCLUSIONS
A fixed-dose regimen of apixaban alone was noninferior to conventional therapy for the treatment
of acute venous thromboembolism and was associated with significantly less bleeding (Funded by
Pfizer and Bristol-Myers Squibb)
FEATURED ARTICLES THIS MONTH
BMJ. 2013 May 23;346:f2907. doi: 10.1136/bmj.f2907.
Consumers' estimation of calorie content at fast food restaurants: cross sectional observational
study.
Block JP, Condon SK et al.
Abstract
OBJECTIVE:
To investigate estimation of calorie (energy) content of meals from fast food restaurants in adults,
adolescents, and school age children.
DESIGN:
Cross sectional study of repeated visits to fast food restaurant chains.
SETTING:
89 fast food restaurants in four cities in New England, United States: McDonald's, Burger King,
Subway, Wendy's, KFC, Dunkin' Donuts.
PARTICIPANTS:
1877 adults and 330 school age children visiting restaurants at dinnertime (evening meal) in 2010
and 2011; 1178 adolescents visiting restaurants after school or at lunchtime in 2010 and 2011.
MAIN OUTCOME MEASURE:
Estimated calorie content of purchased meals.
RESULTS:
Among adults, adolescents, and school age children, the mean actual calorie content of meals was
836 calories (SD 465), 756 calories (SD 455), and 733 calories (SD 359), respectively. A calorie is
equivalent to 4.18 kJ. Compared with the actual figures, participants underestimated calorie content
by means of 175 calories (95% confidence interval 145 to 205), 259 calories (227 to 291), and 175
calories (108 to 242), respectively. In multivariable linear regression models, underestimation of
calorie content increased substantially as the actual meal calorie content increased. Adults and
adolescents eating at Subway estimated 20% and 25% lower calorie content than McDonald's diners
(relative change 0.80, 95% confidence interval 0.66 to 0.96; 0.75, 0.57 to 0.99).
CONCLUSIONS:
People eating at fast food restaurants underestimate the calorie content of meals, especially large
meals. Education of consumers through calorie menu labelling and other outreach efforts might
reduce the large degree of underestimation.
PLoS Comput Biol 9(6): e1003092. doi:10.1371/journal.pcbi.1003092
Mate Choice and the Origin of Menopause.
Morton RA, Stone JR, Singh RS (2013)
Abstract
Human menopause is an unsolved evolutionary puzzle, and relationships among the factors that
produced it remain understood poorly. Classic theory, involving a one-sex (female) model of human
demography, suggests that genes imparting deleterious effects on post-reproductive survival will
accumulate. Thus, a ‘death barrier’ should emerge beyond the maximum age for female
reproduction. Under this scenario, few women would experience menopause (decreased fertility
with continued survival) because few would survive much longer than they reproduced. However,
no death barrier is observed in human populations. Subsequent theoretical research has shown that
two-sex models, including male fertility at older ages, avoid the death barrier. Here we use a
stochastic, two-sex computational model implemented by computer simulation to show how male
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mating preference for younger females could lead to the accumulation of mutations deleterious to
female fertility and thus produce a menopausal period. Our model requires neither the initial
assumption of a decline in older female fertility nor the effects of inclusive fitness through which
older, non-reproducing women assist in the reproductive efforts of younger women. Our model
helps to explain why such effects, observed in many societies, may be insufficient factors in
elucidating the origin of menopause.
Author Summary
The origin and evolution of menopause is understood poorly and explanations remain
contentious. Virtually ignored among explanations is the effect that mate choice can exert on an
evolving population. We designed and used a computational model and computer simulation to
show that male mating preference for younger females in humans could have led to the
accumulation of mutations deleterious to female fertility and thereby produced menopause. Our
model demonstrates for the first time that neither an assumption of pre-existing diminished
fertility in older women nor a requirement of benefits derived from older, non-reproducing
women assisting younger women in rearing children is necessary to explain the origin of
menopause.
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CONCLUSIO
NO ED or TOXICLOGY journal club articles were received in the last month for publication in Précis.
Westmead ED publications this month
None noted or made aware of to Précis.
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