Transcript Percussion pacing*an almost forgotten procedure for

Presented by : Dr Rashmi Bhatt
From: British Journal of Anaesthesia
2007
In his publication from 1920, the physician
Eduard Schott from Cologne, Germany first
described mechanical stimulation of the heart,
which
he
performed,
repeatedly
and
successfully, in a patient with recurrent Adam–
Stokes attacks caused by complete heart block.
 Several case reports and case series have been
published about this technique in the following
decades, percussion (or fist) pacing seems to
remain a ‘forgotten procedure’ in the
management of symptomatic bradycardia or
bradycardic circulatory arrest.
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percussion pacing is still relatively unknown and
does not represent a standard component of the
therapeutic repertoire of most medical
professionals. This is remarkable in as much as
percussion pacing represents an instantly
available and easy to perform procedure for
temporary emergency pacing of the heart in
symptomatic bradycardias, including bradycardic
pulseless electrical activity (PEA) and CHB with
ventricular asystole.
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Case I: On postop day 6, after mechanical aortic
valve replacement, a 78-yr-old female developed
CHB. The intraoperatively inserted epicardial pacing
wires had been removed shortly before. she
presented with marked haemodynamic instability and
recurrent loss of consciousness consistent with classic
Adams–Stokes attacks. During insertion of a venous
sheath and a transvenous electrical pacemaker wire,
percussion pacing was performed as a temporary
intervention.
The patient instantly regained consciousness, and
continuous plethysmographic reading of the pulse
oximeter showed good electromechanical coupling.
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CASE II: Ten days after an aortocoronary bypass operation,
a 65-yr-old female presented for surgical revision of her
sternum. After induction, the patient suddenly developed
CHB associated with marked haemodynamic instability.
percussion pacing was initiated, resulting in rapid
restoration of an adequate mean arterial pressure.
CASE III: a 3-yr-old girl was undergoing percutaneous
closure of a large secundum ASD under GA.
During the procedure, the occluder slipped off the septal
rim and impacted in the right ventricular outflow tract.
During a successful attempt to retrieve the occluder with a
snare catheter, the septal leaflet of the tricuspid valve was
injured, with subsequent CHB and ventricular asystole.
Percussion pacing was started instantly and A good
peripheral pulse was palpable and visible in a continuous
plethysmography signal.
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In a 55-yr-old woman with CHB, Chan and colleagues
compared the three different modes of emergency
cardiac
stimulation:
percussion
pacing,
transcutaneous, and transvenous electrical pacing.
Ventricular stroke volumes calculated with the use of
a previously inserted pulmonary artery catheter, were
comparable for all three techniques.
Whereas chest compressions produce compressions of
the heart with passive expulsion of blood, mechanical
stimulation in percussion pacing generates an almost
physiological situation with electrical impulses
followed by myocardial contractions.
‘Percussion pacing’ and ‘fist pacing’ are used
synonymously. Furthermore, some authors do not
clearly differentiate between ‘percussion (fist)
pacing’ and ‘precordial’, or ‘chest thumping’.
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Percussion pacing is based on the physical
phenomenon of energy transformation; mechanical
energy applied to viable myocardium triggers an
electrical impulse, after an all-or-none principle.
Precordial thumping, which is often confused with
percussion pacing, produces a premature ventricular
beat (PVB), capable of terminating early ventricular
tachycardia, or ventricular fibrillation.
In
percussion
pacing,
rhythmically
applied
mechanical stimuli produce serial PVBs (electrical
coupling), thus generating consecutive contractions
of the myocardium with ventricular ejection
(mechanical coupling).
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In some case reports, one single fist blow terminated
symptomatic bradycardia. However, most authors and
also the European Resuscitation Council (ERC)
recommend serial blows with a rate of approximately
50–70/min.
Compared with precordial thumping, percussion
pacing is performed with less force. To estimate the
required mechanical energy, it is recommended to let
the ulnar side of the fist fall from a height of
approximately 20–30 cm above the chest, on left
lower sternal edge.
Because of its larger force, precordial thumps
intended to terminate tachyarrhythmias are applied
to the mid sternum, whereas for percussion pacing
the lower left sternal edge is recommended,
presumably above the right ventricle.
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increase in right ventricular pressure of at least 15–20 mm Hg
is necessary to generate an electrical impulse in the
myocardium.
the efficacy of percussion pacing must be controlled and
reconfirmed continuously. Mechanical artifacts may render it
difficult to identify percussion-generated QRS complexes (i.e.
electrical coupling), if the ECG leads are attached to the
chest or shoulders. Hence, it seems useful to attach the leads
to the arms and legs, similar to the practice in cardiac
catheterization.
A palpable central or peripheral pulse confirms mechanical
coupling, often visible on the pulse oximeter in a reliable
plethysmographic reading.
an indwelling arterial catheter or a pulmonary artery catheter
may be available for reliable confirmation of the presence of
a pulse with sufficient CO.
Regaining of consciousness in patients suffering Adam–Stokes
attacks is also regarded as a good clinical sign of restitution.
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Percussion pacing is generally indicated in all
haemodynamically unstable bradyarrhythmias, in
particular in CHB with or without ventricular escape
rhythm (‘P wave asystole’).
the presence of atrial activity is regarded as a
prerequisite for successful stimulation. Instantly
started percussion pacing can bridge the time it takes
to establish transcutaneous or transvenous electrical
pacing.
In many patients with bradycardic circulatory arrest
(PEA), percussion pacing can replace chest
compressions until pharmacological or electrical
intervention shows its effect. Particularly, in postcardiac surgical patients, the avoidance of chest
compressions may prevent the serious complication
of an unstable sternum.
If no cardiac stimulation can be achieved in
bradycardic PEA, cardiopulmonary resuscitation
(CPR) must be started immediately.
 Whereas there is a paucity of evidence on
percussion pacing, there exist numerous animal
studies, case reports, and case series to report
on its efficacy. However, partly because of the
ERC’s recent incorporation of percussion pacing
into their 2006 ALS manual, it is likely that this
technique will receive more widespread publicity
and clinical use.
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