Re: external cephalic version
From: Ronnie Martinez Brignardello (ronniem@entelchile.net)
Sun Apr 30 20:34:32 2000
good efrain!! all we can say is ........tan-tan.
ronnie
Efrain Ramirez wrote:
> "What are the success rates for external cephalic version, and what
> factors are
> predictive of either success or failure?
>
> A review of 20 studies indicates that success rates for ECV range from
> 35% to 86%, with an
> average success rate of 58% (4, 6, 9, 12–14, 16–18, 21–25, 27, 29–31).
> Most authors report a
> positive association between parity and successful version (4, 6, 13,
> 21–25, 30, 31). A
> transverse or oblique lie is associated with higher immediate success
> rates (13, 29, 30).
> Opinion is divided about the predictiveness of other factors, including
> amniotic fluid volume,
> location of placenta, and maternal weight. Some reports indicate an
> association between
> normal or increased amounts of amniotic fluid and successful ECV (12,
> 13, 24, 32), whereas
> other reports do not (20). Two authors reported an association between
> successful ECV and
> placenta location (20, 24), whereas others failed to find an association
> (12, 13, 29). Two authors
> found obesity to be associated with a higher failure rate (23, 30),
> whereas others found maternal
> weight not to be a significant predictor of success (12, 13, 19, 20).
>
> Although scoring systems have been developed to predict which candidates
> will have a
> successful version attempt, these have not been validated by multiple
> studies. One system
> considered parity, dilatation, estimated fetal weight, placenta
> location, and station. Nulliparity,
> advanced dilatation, fetal weight of less than 2,500 g, anterior
> placenta, and low station were
> less likely to be associated with success (20). Such variables may
> provide useful clinical
> information for obtaining informed consent from individuals for ECV; no
> single system, however,
> has been shown to have complete accuracy.
>
> How does the use of tocolysis affect the success rate of external
> cephalic version?
>
> Two of six randomized controlled trials failed to find a significant
> advantage in using tocolytics
> during ECV attempts (19, 27). One third reported significantly greater
> success associated with
> hexoprenaline but not with ritodrine (33). An additional randomized
> study reported an initial
> advantage associated with the use of ritodrine, specifically among
> nulliparous women. However,
> as the physicians became proficient at the ECV technique, the advantage
> diminished (34). The
> largest randomized study using a ritodrine infusion found significant
> improvement only among
> nulliparous patients (35). Finally, a randomized study of terbutaline
> found the success rate of
> version associated with use of this tocolytic to be almost double the
> rate without its use (36). In
> the vast majority of published studies, a tocolytic agent was used
> routinely (6, 11–18, 20–23,
> 27–29, 37). Several studies used tocolytics selectively (5, 7, 9, 34),
> and some used no tocolytic
> agents (4, 25). Existing evidence may support the use of a tocolytic
> agent during ECV attempts,
> particularly in nulliparous patients.
>
> How does the use of anesthesia affect the success rate of external
> cephalic version?
>
> A randomized study found a significantly greater success rate associated
> with the use of
> epidural anesthesia, although the success rate was unusually low for the
> women who did not
> receive epidural anesthesia (32%) (38). Two studies reported results
> for women in whom ECV
> was performed while using epidural anesthesia (10, 15). In one study,
> use of epidural
> anesthesia was associated with a significantly greater success rate
> compared with no use of
> epidural anesthesia (15). However, the procedure was administered
> selectively to patients
> according to physician preference, raising the potential for selection
> bias. The other study merely
> noted that ECV was performed without difficulty on three women
> undergoing epidural anesthesia
> (10). It also has been suggested that epidural anesthesia be considered
> for women who failed a
> previous version attempt (39). Another randomized trial addressed the
> use of spinal anesthesia
> before the version attempt and found no significant difference between
> treatment groups (40).
> Currently, there is not enough consistent evidence to make a
> recommendation favoring spinal or
> epidural anesthesia during ECV attempts.
>
> Summary
>
> The following recommendation is based on good and consistent scientific
> evidence (Level
> A):
>
> Because the risk of an adverse event occurring as a result of ECV is
> small and the
> cesarean delivery rate is significantly lower among women who have
> undergone
> successful version, all women near term with breech presentations should
> be offered a
> version attempt.
>
> The following recommendations are based on limited or inconsistent
> scientific evidence
> (Level B):
>
> Patients should have completed 36 weeks of gestation before attempting
> ECV.
> Previous cesarean delivery is not associated with a lower rate of
> success; however, the
> magnitude of the risk of uterine rupture is not known.
> There is insufficient evidence to recommend routine tocolysis for ECV
> attempts for all
> patients, but it may particularly benefit nulliparous patients.
> Evidence is inconsistent regarding the benefits of anesthesia use during
> ECV attempts.
> Cost-effectiveness depends upon utilization of vaginal breech deliveries
> and costs of the
> version protocol at a particular institution, but at least one decision
> analysis suggests the
> policy is cost effective.
>
> The following recommendations are based primarily on consensus and
> expert opinion (Level
> C):
>
> Fetal assessment before and after the procedure is recommended.
> External cephalic version should be attempted only in settings in which
> cesarean delivery
> services are readily available."
>
> At Sat, 29 Apr 2000, Steve & Eryl Raymond wrote:
> >
> >On 27 Apr 2000, at 21:35, Kevin D. Dew MD wrote:
> >
> >> 1. What gestational age?
> >> 2. How soon afterward do you deliver?
> >> 3. What do you use to relax the uterus?
> >>
> >> Trying to get an idea of what people are doing.
> >>
> >The WHO Reproductive Health Library states the following in a
> >meta-analysis of trials involving ECV:
> >
> >Conclusions: There is compelling evidence that ECV attempt at
> >term materially reduces the chance of non-cephalic birth and
> >Caesarean section. The randomised trials to date are too small to
> >address the question of the risk of ECV at term, though published
> >uncontrolled series indicate that this is small. In individual cases,
> >the risk of ECV needs to be weighed against the current and future
> >risks of continued breech presentation to mother and fetus.
> >
>
> >As a result of reading this our policy has been established as
> >follows:
> >1. Attempt ECV only if breech presentation at 37/40.
> >2. If unsuccessful then take to a CTG machine and give Ipradol
> >5mcg. (or another tocolytic) i.v. Within three to five minutes
> >attempt ECV again.
> >3. Run CTG for five minutes if unsuccessful, 20 minutes if
> >successful.
> >
> >My experience has been that a more than 50 % success rate can
> >be achieved with this procedure. It is true that there are occasions
> >where the procedure results in profound distress in the baby. You
> >need to be ready to do a C/S if the FH doesn't respond to turning
> >on the side and/or oxygen administration. This is excessively rare.
> >Had to do it once in 20 years. Timing of delivery is no different then
> >from your standard cephalic presentation.
> >
> >Steve Raymond
>
> --
> "The things you learn after you know everything are the important ones"
|
|
