Evidence-Based Medicine

FPIN Journal Club
Title: Suctioning neonates at birth: Time to change our approach
PURL Author: Iliana Neumann, MD;Anne Mounsey, MD; Niladri Das, MD
PURL Citation: J Fam Pract. 2014;63:461-462
Original Article: Oronasopharyngeal suction versus wiping of the mouth and nose at birth: a
randomised equivalency trial. Kelleher J, Bhat R, Salas AA, Addis D, Mills EC, Mallick H,
Tripathi A, Pruitt EP, Roane C, McNair T, Owen J, Ambalavanan N, Carlo WA. Lancet. 2013 Jul
PURL Journal Club Author: Sarah-Anne Schumann, MD University of Oklahoma Tulsa,
Department of Family Medicine
PURL Journal Club Editor: Corey Lyon, DO University of Colorado, Department of Family
1. What question did the study attempt to answer?
Patients – vigorous neonates born after 35 weeks with no major anomalies or meconium
Intervention – wiping nose and mouth with towel
Comparison –oropharyngeal bulb suctioning
Outcome –mean respiratory rate in the 24 hours after birth
Did the study address an appropriate and clearly focused question
2. Determining Relevance:
a. Did the authors study a clinically meaningful
and/or a patient oriented outcome?
b. The patients covered by the review similar to your population
3. Determining Validity:
Study design;
a. Was it a controlled trial?
It was a “randomized equivalency trial”
b. Were patients randomly allocated to
comparison groups?
randomized before delivery
c. Were groups similar at the start of a trial?
d. Were patients and study personnel “blind” to treatment?
e. Aside from allocated treatment, were groups treated equally?
f. Were all patients who entered the trial properly accounted for at it’s conclusion
4. What are the results?
a. What are the overall results of the study?
This was an equivalency trial, testing 2 interventions to ensure that they are equivalent.
For the primary outcome they found a respiratory rate (RR) of 51 in the wipe group and a RR of
50 in the suction group.
Apgar scores at 1 minute 8 vs 8; p=0.55, 5 minute 9 vs 9; p=0.27
Median (interquartile rage) oxygen saturation at discharge 100% (99-100) vs 100% (99-100)
Advanced resuscitation required at birth 24 (10%) vs 17 (7%); Relative Risk 1.40 (CI 0.76-2.50)
p=0.28 – no difference between groups – seen by the nonsignificant p value and the RR
confidence interval crosses 1.
NICU admission required 45 (18%) vs 30 (12%); RR 1.5; 95% CI 0.96-2.30; P=0.07; no difference
between groups – seen by the nonsignificant p value and the RR confidence interval crosses 1.
b. Are the results statistically significant?
c. Are the results clinically significant?
d. Were there other factors that might have
affected the outcome?
there was a high crossover rate. The rate was 20% with 34 undergoing wiping in the suction
group and 64 undergoing suction in the wipe group. This is addressed in the study
5. Applying the evidence:
a. If the findings are valid and relevant, will this change
your current practice?
b. Is the change in practice something that can be done in
a medical care setting of a family physician?
c. Can the results be implemented?
d. Are there any barrier to immediate implementation?
change in the delivery room)
e. How was this study funded? Not funded
No (culture
6. Teaching Points
Noninferiority Studies
 The usual therapeutic study is designed to determine superiority: is arm A or B more
 In some cases, we aim only to prove equivalence, not superiority. This can be if a new
treatment is:
o More patient-friendly
o Cheaper
o More easily available
o Less invasive
** in this study, wiping the nose and mouth applies to all of the above criteria
Non inferiority trials are used when a new treatment has an advantage, asides from
possible treatment efficacy, over the current standard treatment so one might accept a
small decrease in the efficacy of the newer treatment because of this advantage.
Reasons for Choosing a Non-Inferiority Design
o Showing non-inferiority of the experimental treatment E versus the control
treatment C can be of interest because of the following:
 It is not ethically possible (anymore) to do a placebo controlled trial.
 Experimental treatment is not expected to be better than Control on a
primary efficacy end point, but is better on secondary end points or is
safer. (Provide example from article here)
 Experimental treatment is not expected to be better than Control on a
primary efficacy end point but is cheaper to produce or easier to
 Experimental treatment is not expected to be better than Control on a
primary efficacy end point in a clinical trial, but compliance will be better
outside the clinical trial and hence efficacy will be better outside the
In this study, there was a predetermined range of clinical equivalence for the mean
respiratory rate in the first 24 hours after birth
Teaching point #2,3: p values and primary and secondary outcomes
From the PURL: “More neonates in the wiping group than in the suctioning group were admitted
to the neonatal intensive care unit (45 of 246 [18%] vs 30 of 242 [12%]; P=.07), but the study
was not powered to assess this outcome.”
P Value: the probability of getting the results you did given that the null hypothesis is true. Put
simply it’s the chance that the relationship you are observing is observed by pure chance. So if
you obtain a p-value of 0.01, it means that there is a 1% chance that the relationship between
the experimental group and the control group doesn't actually exist. It is important to note that
a p value is attempting to show a statistically significant difference, but it does not show the
magnitude of effect (ie place example here from the article) or show the direction of the
difference. This is why data like Odds Ratios, Hazard Ratios, NNT or more useful statistics than a
p value.
A p value determines the difference between 2 groups.
Difference between primary outcomes and secondary outcomes; the primary outcome is the
outcome of greatest importance and it is these outcomes that the study is powered. Data on
secondary outcomes are used to evaluate additional effects of the intervention, however, a
power calculation is not usually calculated for these outcomes, so should be interpreted with a
little more caution.
In this study, while the primary outcome and the other secondary outcomes are close to
identical, a higher percentage of babies in the wiping group were admitted to the NICU than in
the suctioning group, but the p value of 0.07 is >0.05 and therefore not statistically significant.
Readers have to decide if this difference might still be large enough to question whether this
study is robust enough to change current practice.