536 Abstracts

year of birth, gender, and physician’s practice. Potential con-founders including mother’s age, gestational age, medicationsduring pregnancy, perinatal injury, and Apgar score were evalu-ated. All exceptmother’s education had a statistically significantassociation and were carried into the final model. Using condi-tional logistic regression, odds ratios were calculated for novaccine; monovalent measles vaccine; and measles, mumps, ru-bella (MMR) vaccine. The risk of autism in vaccinated vs. non-vaccinated children (independent of vaccine type) was 0.28(95% confidence interval [CI] 0.10–0.76). The risk connectedwith being vaccinated before onset of first symptoms was signif-icantly lower only for MMR versus single vaccine (odds ratio0.47, 95% CI 0.22–0.99).

[Marlow Macht, MD

Denver Health Medical Center, Denver, CO]

Comment: This study was able to take advantage of the lateadoption of theMMR vaccine in Poland to compare autism ratesamong unvaccinated children, as well as those vaccinated witheither the MMR or monovalent measles vaccines. This ad-dresses a concern raised by a now-retracted article byWakefieldet al. and adds to the body of evidence that has failed to showa relationship between measles vaccination and autism (1,2).This article is an example of the significant resources that canbe diverted to disproving an unfounded theory that has beenharmful to the public’s heath. Sadly, those who continue toinsist on a link between vaccines and autism will likelycontinue to ignore the results of studies like these perpetuatingthe cycle.

REFERENCES

1. Retraction—Ileal-lymphoid-nodular hyperplasia, non-specific coli-tis, and pervasive developmental disorder in children. Lancet 2010;375:445.

2. Wakefield AJ, Murch SH, Anthony A, et al. Ileal-lymphoid-nodularhyperplasia, non-specific colitis, and pervasive developmental disor-der in children. Lancet 1998;351:637–41.

, QRS PROLONGATION IN PATIENTS WITH ACUTECORONARY SYNDROMES. Baslaib F, Alkaabi S, CasanovaA, et al. Am Heart J 2010;159:593–8.

This study used data from the Canadian Acute CoronarySyndromes (ACS) Registry to evaluate the relationship betweenQRS duration, with and without left or right bundle branchblock (BBB), and 1-year mortality in ACS. In the study, 5003patients were admitted to the hospital for ACS. The authors di-vided these patients into four groups: QRS < 120 ms (n = 4289),QRS > 120 ms without BBB (n = 202), left BBB (n = 262), andright BBB (n = 250) based on their initial electrocardiogram.These groups were evaluated for predictive value of in-hospitalmortality and 1-year mortality. By group, in comparison toQRS < 120 ms, patients with QRS > 120 ms without BBB hada non-significant increased in-hospital risk of death (odds ratio[OR] 1.87, 95% confidence interval [CI] 0.85–4.09) and hada significantly higher risk of 1-year mortality (OR 2.10, 95%CI 1.38–3.18). For left BBB (LBBB) and right BBB (RBBB),

both in-house and 1-year mortality were significantly higher(LBBB unadjusted OR 2.71 and 3.41, respectively, withp = 0.001 and RBBB unadjusted OR 2.62 and 2.25, respectively,with p = 0.001). After adjusting for other independent risk fac-tors for cardiac death, patients with LBBB were the only popu-lation with a significantly higher risk of 1-year death (OR 1.93,95% CI 1.28–2.90, p = 0.002). When QRS was evaluated asa continuous variable, a significant increase was found in riskof death at 1 year per 10-ms-interval increase (OR 1.11, 95%CI 1.06–1.16, p < 0.001). The authors conclude that QRS pro-longation, especially in the setting of LBBB, is an independentpredictor of in-hospital and 1-year mortality.

[Whitney Barrett, MD

Denver Health Medical Center, Denver, CO]

Comments: This study looks at a very large number of pa-tients, and from those large numbers makes a convincing argu-ment for the role of QRS as a risk factor for mortality in patientsadmitted for acute coronary syndromes. Whereas risk associ-ated with LBBB alone had previously been established, therole of QRS prolongation in general is new. The outstandingquestion is whether these data will impact the way in whichwe risk-stratify patients in the future or if this information couldprove useful in impacting long-term outcomes.

, HEAD-POSITION ANGLES IN CHILDREN FOROPENING THE UPPER AIRWAY. Paal P, Niederklapfer T,Keller C, et al. Resuscitation 2010;81:676–8.

The most common cause of pediatric arrest is primary respi-ratory arrest, and adequate ventilation via bag valve mask is ofprime importance in resuscitations. Conventional teaching dic-tates that when ventilating pediatric patients, a neutral positionfor young children vs. slight head extension in older childrenshould be utilized. This study compared ventilatory parametersin various-aged children placed in neutral (mean 6 SD:1.3 6 6.0) and extended head positions (13.2 6 6.0;p < 0.001) in hopes of determining ideal head positioning forchildren of varying ages. Sixty-one children undergoing generalanesthesia for tonsillectomy were divided into two groups: pre-school children ages 1–5 years (n = 38) and school children ages6–10 years (n = 23). Various respiratory variables were mea-sured via a pulmonarymonitor attached to a pneumotachograph,and the presence of stomach insufflation was documented over1-min periods in both neutral and extended head positions.Among preschool-age children, tidal volumes, peak-expiratoryflow, and expiratory airway resistance were similar for neutralvs. extended head positions. For school children, the differencein expiratory airway resistance was statistically significant(17 6 7 vs. 13 6 5 cm H2Osl

�1; p = 0.048), but tidal volumesand peak-expiratory flow were similar. The frequency of stom-ach insufflation was not statistically different between neutralvs. extended head positions in either age group. The authorsconclude that their results are consistent with conventionalteaching, with the exception that among preschool-age children,head positioning may not matter as much as previously thought.A described future application of this study is that investigators