Archive | January, 2013

Acetaminophen vs Ibuprofen

31 Jan

nice recent post on these two as antipyretics at PEM Blog.


“the FDA has only approved ibuprofen for use in children older than six months of age. In all honesty a single dose in a euvolemic, non septic 4 month old shouldn’t cause kidney injury… But it’s your license  ;-)”


“both drugs cleared fever 23 minutes faster than acetaminophen alone, but no faster than ibuprofen. The combination when given regularly together over 24 hours also resulted in less time with fever vs either drug alone.

So yes, you can use both simultaneously, but the benefit isn’t startlingly great, and this is a surefire way to get confused about how much medicine you are giving the child.”


“So who wins? Well, for a single dose in a child >6 months with fever I prefer ibuprofen alone (by the slimmest of margins). I don’t alternate, nor do I give both at the same time. Ultimately both drugs are safe and effective…”



Ibuprofen (10 mg/kg)

acetaminophen (10-15 mg/kg)



References: PEM Blog post; picture


nebulized epinephrine dosing for croup

30 Jan

2011 Cochrane Review:


  • Compared to no medication, inhaled epinephrine improved croup symptoms in children at 30 minutes following treatment
  • This treatment effect disappeared two hours after treatment 
  • However, children’s symptoms did not become worse than prior to treatment



aerosolized epi works at alpha-adrenergic receptors in subglottic mucosa

vasoconstriction -> decreased edema -> less stridor

quick onset: < 10 min



Croup (laryngotracheobronchitis) is a common respiratory illness of childhood

clinical picture is characterized by the abrupt onset of a distinctive barky cough, which may be accompanied by stridor

often preceded by non-specific symptoms such as cough, rhinorrhea and fever. 

most common etiology is a viral infection, predominantly parain-fluenza virus



Studies used:

  • 0.5 ml of 2.25% racemic epinephrine
  • 0.5 mg/kg of 2.25% racemic epinephrine
  • 0.25 ml of 2.25% racemic epinephrine per 5 kg of body weight
  • 5 ml of 1:1000 dilution of L-epinephrine
  • 0.25 ml of 2.25% of racemic epinephrine 

most common dose: 0.5 mL of 2.25% racemic epi



Small ICU study (96 patients) on post-extubation stridor in kids

Nebulized L-epinephrine at doses of 0.5, 2.5 and 5 ml demonstrated a lack of dose response in effect on PES and a modestly clinically significant increase in undesired side effects (heart rate and blood pressure) at higher doses.”



References: Rosen’s Emergency Medicine (2011); cochrane review; small ICU study; picture

Is water effective for wound cleansing?

29 Jan

Nov 2012 Annals commentary on Cochrane review




tap water, distilled, cooled boiled water, normal saline solution: no statistically significant difference



click through to read the review/commentary, but overall, RR (relative risk) of infection for water vs. saline is ~1.0 or less.


References: annals commentary, cochrane review, picture.

abdominal pain duration and the accuracy of imaging in pediatric appendicitis

28 Jan

Article by Bachur et al:

The effect of abdominal pain duration on the accuracy of diagnostic imaging for pediatric appendicitis.

duration of abdominal pain is associated with severity of disease (risk of appendiceal perforation generally after 24-48 hrs duration of symptoms)

makes sense that the angrier/more inflamed the appendix gets, the easier it is to see on imaging (particularly ultrasound)



1,810 children (age 3-18)

  •  1,216 (68%) assessed by CT
  • 832 (46%) by ultrasonography
  • (238 [13%] had both) 



  • in kids with suspected appy, CT is highly sensitive regardless of symptom duration
  • ultrasound is less sensitive with <48 hrs pain


References: Annals article; picture

does flexed/extended positioning matter for LP opening pressure?

24 Jan

BOTTOM LINE (at the top): not really. not much.

STUDY 1: (Avery et al.)

53 children had their opening pressure measured in both the flexed and extended lateral recumbent positions (mean age = 11.7 years)

mean opening pressure was higher in the flexed (25.1 +/- 9.2 cm H2O) compared with the extended (24.4 +/- 8.4 cm H2O) position

Most (92.4%) opening pressure measurements had less than a 5 cm H2O difference between positions.

a statistically significant decrease in cerebrospinal fluid opening pressure, although the magnitude of the difference is small and of doubtful clinical significance


STUDY 2: (Sithinamsuwan P et al.)

(n = 83) underwent lumbar puncture while in the flexed lateral decubitus position and then were moved to the relaxed position.

Mean pressures for Flexed and recubment position were 178.54 and 160.52 mmH2O respectively, p <0.001.

authors recommend an equation…or using 200 mmH2O as the threshold for increased ICP with flexed posture.

if 20mmH2O is your upper limit threshold for opening pressure, the difference doesn’t matter much.



References: study 1, study 2, picture

just to scare you: saddle PE that didn’t read the textbook

23 Jan

case report in Annals of Emergency Medicine by Hennessey et al.:

PERC Rule = clinical decision rule used to identify patients low-risk for PE, where D-dimer is unnecessary

  • Age <50
  • Pulse <100
  • 02 sat >94%
  • no unilateral leg swelling
  • no hemoptysis
  • no recent trauma/surgery
  • no previous PE/DVT
  • no exogenous estrogen (e.g. OCPs)

if all 8 negative = low risk

may miss 1-2% of PEs, but suggested these would be low mortality/low clot burden patients



42 yo F

chief complaint: chest pain, x 1 day

relieved with Pepto x2, recurred overnight, came to ED

CP 8/10, non-exertional, non-pleuritic, pressure

minimal SOB with speaking, no DOE


PMHx: HTN, anemia, etc.

No hx DVT, no OCPs, family hx unremarkable


VS 115/73, P 92, AF, 100%/RA


Labs unremarkable, troponin negative

low risk Well’s, PERC negative


resident ordered D-dimer prior to attending chat

D-dimer resulted at upper limit of lab testing ability (VERY HIGH)

CTA: multiple L central & subsegmental PEs, large R saddle embolus


inpatient Echo: nml, no RV enlargement


5 wk later, returned to ED for CP: INR therapeutic, resolution of PE’s on CTA



  • clinical decision rules are low-risk, not NO risk
  • accept some tiny risk of missing something when you use these, at the benefit of not irradiating everyone
  • good luck


References: case report; PERC rule; Well’s Criteria; picture

Pain over speed bumps in diagnosis of acute appendicitis

22 Jan

that this study (from the BMJ) exists in literature is awesome, in my opinion:

Ashdown HF, et al:

101 patients aged 17-76 years referred to  surgery for possible appendicitis.

64 participants who had traveled over speed bumps on their journey to hospital.

54/64 (total participants) were “speed bump positive.”



34/64 had a confirmed histological diagnosis of appendicitis

33/34 (with appy diagnosis) reported increased pain over speed bumps.


  • sensitivity was 97% (95% confidence interval 85% to 100%),
  • specificity was 30% (15% to 49%)
  • positive predictive value was 61% (47% to 74%),
  • negative predictive value was 90% (56% to 100%).
  • likelihood ratios were 1.4 (1.1 to 1.8) for a positive test result and 0.1 (0.0 to 0.7) for a negative result. 
  • Speed bumps had a better sensitivity and negative likelihood ratio than did other clinical features assessed, including migration of pain and rebound tenderness.


Presence of pain while travelling over speed bumps was associated with an increased likelihood of acute appendicitis.

As a diagnostic variable, it compared favourably with other features commonly used in clinical assessment

OLD POST ON positive likelihood ratios FOR SIGNS/SYMPTOMS OF APPENDICITIS, for those interested.


“speed bump sign”

  • good sensitivity
  • bad specificity
  • about as good as our other clinical signs on its own (which is not terribly good)
  • as an isolated finding, take it with a grain of salt, but worth adding to your collection of clinical findings

my two cents: 

  • I sometimes jostle or kick the bed/stretcher of my abdominal pain patients as a sideways eval of peritoneal irritation or abdominal discomfort, so its nice to know there might be some small evidence it could be somewhat useful.

References: bmj article; picture