Abstract
Objective: to evaluate the efficacy of spontaneous pushing with
pursed lips breathing compared to directed pushing during the second
period of labor in the occurrence of episiotomy.
Methods: this is a quasi-randomized clinical trial, with 62
low-risk pregnant women in the second stage of labor. They were randomly
allocated in control (CG) (n = 31) and intervention (IG) (n = 31)
groups. The IG performed spontaneous pushing with pursed lips breathing
while the CG was oriented to perform directed pushing associated with
Valsalva Maneuver (MV).
Results: There was no difference between the groups regarding
the occurrence of episiotomy (RR 1,1; 95%IC 1,0 to 1,2). However, there
was a decrease in the duration of the maternal pushing by 3.2 minutes
(MD 3,2; 95%CI 1,4 to 5,1) and a difference in maternal anxiety (Md
(IQR) IG 46 (35-52), CG 51 (44-56) p:0,049), both favoring the IG. There
was no difference in others maternal and neonatal outcomes
Conclusions: spontaneous pushing with pursed lips breathing was
effective in reducing the duration of the pushing and showed a
difference in maternal anxiety, but did not decrease the occurrence of
episiotomy, nor did it alter the other studied maternal and neonatal
outcomes.
Brazilian Clinical Trials Registry (ReBEC) under the
identifier: RBR-556d22.
Keywords: Labor, Obstetric; Labor Stage, Second; Respiration;
Parturition; Spontaneous Pushing.
Funding statement: the study had no funding body.
Introduction
Maternal pushing has been
discussed for decades, mainly about its relevance in facilitating care
in the second stage of labor and maternal and fetal outcomes [1,2].
In 1957, Beynon was the pioneer to compare the pushing done
spontaneously with the Valsalva maneuver (VM), leading to a discussion
about imposed breathing patterns associated with expulsive efforts and
their relationship with the integrity of the pelvic floor. That study
initiated a reflection on the importance of changing pushing
instructions in obstetric care [3,4].
Directed pushing is common practice in obstetrics worldwide and it is
done independently of the maternal desire to carry out the expulsive
effort. It is usually associated with a VM sustained for 10 seconds or
more and is oriented by third parties [4-6].
Recently in 2018, the World Health Organization (WHO) recommended that
women in the expulsive phase of the second stage of labor should be
encouraged and supported to follow their desire to push. According to
the WHO, qualitative evidence shows that it is important for women to
feel in charge of childbirth. The recommendation mentions that due to
the absence of evidence of any benefit of imposing directed pushing in
the second stage of labor this technique should be avoided by health
professionals involved in childbirth care [7].
Spontaneous pushing is carried out naturally by the woman according to
the inevitable desire to push down progressively. There is no deep
breathing, and it does not initiate right at the beginning of the
contraction. Generally, three to five pushings occur starting at the
peak of the contraction and mostly happen with open glottis. [4-6].
In this scenario, the idea of using pursed lips breathing arises, which
consists of a nasal inspiration followed by a resisted exhalation
performed with pursed lips and/or semi-closed teeth, which may occur
with or without contraction of the abdominal muscles [8] to
facilitate spontaneous pushing during the expulsive effort, but studies
are still scarce [2]. There is a study that compared a relaxation
technique with breathing exercises, which involved diaphragmatic
inspiration, prolonged fractional expiration, and pursed lips breathing
with usual care but observed only during the first stage of labor
[9].
Several physiological effects are related to pursed lips breathing in
several populations, such as improvement of breathing patterns,
reduction of dyspnea sensation, global relaxation, positive expiratory
pressure maintenance, preventing alveolar collapse while promoting lung
deflation [8]. Also, an increase in arterial oxygen pressure and
arterial oxygen saturation, decreased carbon dioxide pressure, decreased
respiratory rate and increased tidal volume were observed [10], in
addition to changes in respiratory mechanics, with greater activation of
the abdominal, rib cage and accessory expiratory muscles, and lower
diaphragmatic participation, which may be useful to prevent respiratory
fatigue [11,12].
Therefore, given the physiological benefits of pursed lips breathing
described in the literature, we hypothesize that its use during the
second stage of labor may result in better maternal and neonatal
outcomes and thus provide the necessary evidence for its guidance.
Given the gaps in knowledge resulting from the high risk of bias in the
studies regarding the type of pushing, the present study aimed to
evaluate the efficacy of spontaneous pushing with pursed lips breathing
when compared to directed pushing on maternal and neonatal outcomes.
Materials and methods