Hi Sheila
It is an interesting question that you ask and of interest to me in my
PhD studies. I agree with the feedback from Rachel, Pamela, Mary Doyle
and Mary Kathleen Longworth.
The only refernce I have found in my reading of the use of Pinard as
part of a full fetal heart rate monitoring package (although not linked
to any specific research study) comes in Gibb and Arulkumaran (2008)
Fetal Monitoring in Practice. 3rd edition. Oxford: Elsevier (pages
12-15). It comes in the context of admission asessment and risk
assessment and they say:
"The importance of clinical sense cannot be over emphasized. Figure 2.4
[a picture of a CTG machine with a tape measure and Pinard]shows the
'complete' CTG machine including an accompanying tape measure and fetal
stethoscope. Why the fetal stethoscope? The CTG shown in figue 2.5
[picture of a CTG with FHR looking OK with good variability] was
undertaken in a mother admitted complaining of reduced fetal movements.
The fetal stethoscope was not used and the ultrasound transducer was
applied directly to the maternal abdomen.The mother was reassured that
the baby was healthy; however a macerated stillbirth occurred 1 hour
later. The heart rate picked up was the maternal pulse from a majot
vessel with the ultrasound beam having passed through the dead
fetus...The stethoscope must always be used to establish a fetal puls
different from the maternal pulse".
This excerpt below, from my recent publication explains a bit more about
what is heard when using a Pinard or Ultrasound device:
The technique of IA, sometimes referred to as periodic listening,
generates information by listening to and counting the foetal heart
sounds through the maternal abdomen, for a specified number of seconds
at a specified time, in relation to uterine contractions. IA is
conducted with either a foetal stethoscope (fetoscope) or a hand-held
ultrasound device. Non-electronic auscultation, such as the application
of a Pinard's fetoscope to the maternal abdomen for periods of up to
one minute or more, allows practitioners to hear the sounds associated
with the opening and closing of the ventricular valves in the foetal
heart, via bone conduction, with each foetal cardiac cycle. With this
type of device, the midwife can hear the actual fetal heart sounds,
including any abnormal heart beat rhythms. Electronic devices such as
the hand held Doppler applied to the maternal abdomen use ultrasound
technology to listen to the reflected and amplified sounds of the motion
within the fetal heart, such as the moving heart walls or valves. The
information received by the Doppler device is converted into a sound
that is heard and displayed as a representation of the foetal cardiac
cycle11
So this, I think, helps to provide a rationale for the use of Pinard
before CTG.
I must say though that I fully agree with Mary Doyles comments below:
"The fundamental issue is the need to retain the skills of listening
with a pinard and giving credit to this as a viable means of identifying
and auscultating a fetal heart in addition to the use of other
technologies as appropriate".
This is really the crux of my thesis. I beleive Intermittent
Auscultation (IA) of the fetal heart rate is a fundamnetal midwifery
skill which is underpinned by the Keeping Birth Normal message. Midwives
have/are becoming deskilled in the art and science of IA due to many
reasons [increased use of technology, medico-legal fears, lack of 1 to 1
care etc] but I think we need to return to the basic skills of using
our hands, ears and eyes (and other senses). This is what I am doing in
my study by way of an education package and a model for intelligent,
structured IA.
Cheers, Robyn Maude
-----Original Message-----
From: A forum for discussion on midwifery and reproductive health
research. [mailto:[log in to unmask]] On Behalf Of Sheila
Stewart
Sent: Monday, 26 April 2010 08:27
To: [log in to unmask]
Subject: ascultation of FHR prior to attaching CTG
Hi,
I am trying to find evidence of why the FHR should be ascultated by a
hand held doppler/sonicaid or pinnards before applying the ultrasound
transducer when attaching a fetal monitor. Why is asculating with an
ultrasound doppler/sonicaid so different from ascultating with the U/S
transducer of a EFM? It is the policy on the unit I work on to take the
maternal pulse and doucment it when attaching EFM to differentiate FHR
from maternal pulse. I would appreciate any information on this.
Thanks
Sheila
(midwife, North Wales)
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