EXTERNAL
CARDIAC
COMPRESSION
Method
,Results,
and Complications
Manning Michael Thaler, M.D.
Pathology Department, Hospital for Sick Children, Toronto, Ontario
(Submitted April 19; accepted for publication July 20, 1962.)
ADDRESS: 555 University Avenue, Toronto 2, Ontario.
PEDi&mzcs, Febmary 1963
303 r HE EMERGENCY MANEUVER known as
closed-chest cardiac massage, or more
accurately, external cardiac compression,
has become widely accepted and practiced
by both medical and lay personnel since
its description in 1960.’ As treatment of
cardiac arrest, this procedure has obvious
advantages over thoracotomy; it is simpler,
safer, and applicable in or out of hospital,
without tools or special preparation. More
importantly, tile few precious moments
spent in making the diagnosis and the
de-cision to open tile chest can instead be
utilized for immediate treatment. A further
consideration is the avoidance of injury to
the myocandium; of 60 hearts which had
been massaged through the open wall of
the chest, only 16 were free of traumatic
2
External cardiac compression is
particu-larly useful in pediatric patients, where
cases of “sudden death,” asphyxia, electric
shock, and severe electrolyte disturbance
are not infrequent. Cardiac catheterization
of children with congenital heart disease is
a potential source of asystole on ventricular
fibrillation. Pediatric surgical procedures
often involve tile respiratory passages,
where a high incidence of cardiac arrest is
likely to result from hypoxia or vago-vagal
reflexes. The technique of “pumping” the
heart may be applied not only in cardiac
standstill but in conditions of shock, where
the maintenance of a strong pulse is of
prime importance.
METHOD
The exact definition of cardiac arrest is
still controversial. It may take the form of
asystole, ventricular fibrillation, or extreme
hypotension. In practice, any patient
with-out a pulse or pnecordial heartbeat should
be immediately treated with external
car-diac compression in order to maintain the
circulation. The only contraindications are
pneumothorax and intrathoracic
liemor-nhage. An interval of about 4 minutes may
elapse before irreversible damage to the
central nervous system results, or less if
hypoxia is present prior to cessation of
ef-fective blood flow. Of equal importance
to cardiac massage is maintenance of
yen-tilation, which may be done by
mouth-to-mouth, face mask, or tracheal intubation
methods.
The technique of rhythmic compression
of the heart consists of a few deceptively
simple-appearing steps, which must be
per-formed correctly to be effective and
atrau-matic.
1. The patient should be supine on a
hard surface, which may, if possible, be
tilted so that the subject’s head is about 10
degrees below the horizontal plane
(Tren-delenberg position).
2. The heel of one hand is placed on tile
lower sternum, in the mid-line, just
ceph-alad to the xiphoid (Figs. 1 & 2). Infants
may be resuscitated by the pressure of two
fingers only. In younger children pressure
applied by one hand is usually sufficient.
If necessary, the other hand may be placed
on top of the first with the heels
superim-posed (Fig. 3).
3. The arms are kept in an extended
po-sition, and the sternum only depressed
ver-tically downward with a strong, thrusting push transmitted through the heel followed
by a sudden release. Gradual squeezing
FIc. 1. The heel of one hand is placed on the
sternum, in tile mid-line, just cephalad to the xyphoid. Pressure from one hand is usually sufficient.
..-i
__44 \
,
FIG. 2. TIle arm is held extended, and no pressure is applied by the fingers.
304
applied by the fingers, so that the ribs are
left free.
4. Compression is repeated approximately
50 times per minute. With each motion the
sternum is depressed 3 to 5 cm, squeezing
the heart between it and the vertebrae. A
recommended method of maintaining the
rllythm of the cardiac compression and
ar-tificial respiration is to inflate the lungs
after every four compressions, which are
performed at approximately one-second
in-tervals. In tilis way, the lungs are ventilated
at tile rate of 12 per minute.3
5. The maneuver should be continued
for at least one hour, proi(lecl the time
elapsed before treatment began does not
exceed 4 to 5 minutes or the primary
dis-ease make the patient unsalvageable.
Ob-servation of pupils affords a quick
evalua-tion of the adequacy of the massage;
dilata-tion indicates insufficient cerebral blood
flow. The pulse may be checked by
palpat-ing the femonal or carotid arteries. A more
convenient way of monitoring tile
effective-ness of tile pulse is to attach a
sphygmoma-nometer to the I)atients arm, and inflate it
to 90 to 100 mm. Each compression of the
heart should be followed by a pulsation of
tile indicator needle, showing the pressure
achieved.’ 5
6. When ilelp is available, an
electrocan-diogram should be taken. Ventricular
fibnil-FIG. 3. If necessary, the heels of both Ilands may
Turk &Glenis”
Stahlgren & Angelchik’3 Stephenson et al.”
Roberts & Greenberg27
Rackow et al.’5
Stone”
4’2
70
I,200
70*
76
148
11
9
‘2.50 26 ‘25
‘20 26
13.3
33 33
18.5
* Approximately.
lation, if discovered, can then be treated
with an external defibrillator.11 If the heart
does not respond witll spontaneous
pulsa-tions after several minutes of compression,
5 ml of 10% calcium chloride and 1 to 2
ml of 1 : 10,000 epinephnine solution may be
injected into tile myocardium to stimulate
contractions.3’
Incidence
COMMENT
When Kouwenhoven Ct al.I published
their description of closed-chest cardiac
massage in 1960, they stimulated
investiga-tions which have resulted in oven 50 articles
in the adult literature. Sucil interest in a
metilod of treatment suggests the extent
and urgency of the problem.
The Ilumber of cases of cardiac arrest
occurring yearly in the United States has
been estimated at 3,000 to 10,000. These
estimates tend to be on the conservative
side, consisting mainly of arrests during
anesthesia and the occasional case of
sue-cessful resuscitation outide the operating
room. The terminology is still not exactly
defined, and only since 1952 has acute
ear-diac arrest been coded by number in tile
Standard Nomenclature of Diseases and
Operations of the A.M.A. As a result, many
hospital records are inadequate, listing
cases of cardiac arrest as “sudden death,”
“asphyxia,” “anaesthetic death,” “coronary
tilrombOsis, “cerebral vascular accident,” or
“pulmonary embolism.” Most surveys of
cardiac arrest occurring in adults during
anesthesia quote an incidence of 1 in 1,500
to 1 in 2,500 operations under general
an-eStile5ia.10 Some series give an even
greater incidence, such as 1 in 850
opera-tions at the Philadelphia General
Hospi-tal,IS or 1 arrest in 1,200 operations during
a 30-year period at the Massachusetts
Gen-eral Hospital.
It is possible that in the pediatric age
group tile incidence of cardiac arrest is
even higher, as suggested by several
au-h13’ n; Rackow Ct al.15 ilave recently
shown in a careful study that the rate of
cardiac arrest during anesthesia in infants
is sigmficantly higher than in older
cliii-dren or adults. Among 25 cases of cardiac
arrest, infants under 1 year of age had an
incidence of 1 in 600, while the case rate
of 1 in 1,700 found in olden children was
statistically comparable to the adult rate
in the same hospital. With the exception of
tilis report, studies of cardiac arrest in
chil-dren do not mention the proportion of
pedi-atnic to adult surgical procedures during
which arrests occurred. This makes the
calculation of comparative ineidences
im-possible.
Stephenson et al., in the most
exhaus-tive study of cardiac arrest to date, showed
that 21% of 1,200 cases of cardiac arrest
drawn from 30 large hospitals occurred
dun-ing the first decade of life. In Table I other
percentage figures are collected. These
fig-ures include cases which occurred during
cardiac surgery. Series of cases of cardiac
arrest in children and infants indicate an
incidence of approximately 1 in 1,500 to 1
in 2,500 (Table II), similar to statistics for
adults. All series agree that the nate of
car-diac arrests complicating cardiac surgery is
far greater than during general surgery
(Table III). In these cases, arrest usually
oc-curs as ventricular fibrillation.
Most authors feel that the incidence of
cardiac arrest is increasing.8’ 17 Because
of better methods of reporting and the
greaten awareness of tile condition, this
in-crease may be more apparent than real. A
TABLE I
PEUCENTAGE OF PEDIATuIc CAMLs IN LARGE
Sau:s OF C&uDItc A1IIIFsT
Source
Total
C’ases (no.)
Pediatric Ca.ses
TABLE II
SuItvIvAIi* IN PEDIATRIC CASES OF CARDIAC AIuIKST
Source (‘ases (no.) . Incidence Among . Surgwai Operations 1’ears of study Surriral. Complete No. % . Partial No. % Peabody’
Snyder et al.’7
Raehoweta/.’5
Roberts & Greenberg27 Turk & Glenn’2
6 66 (47)* 5 3 11 1:1,347 1:1,504 1:1,381 ? 1 : 1 ,900
5 8 10 7 5 18 8* 4 8 1 50 17* 16 12 9 .. ()* 4 2 0 .. 0* 16 8 0
* Last 4 years of survey, when cardiac massage was used.
series of 66 cases of cardiac arest in
chil-dren collected over 23 years in two
chil-dren’s hospitals showed a fourfold
in-crease during the last 5 years of the survey.
The large number of cardiac surgical pno
cedures included may account for this in-i
crease. Thirty-five of 58 cases of cardiac
arrest during the last 18 years of this survey
were associated with surgical correction of
congenital cardiac malformations.
RESULTS
To determine the usefulness of external
cardiac compression, its results must be
compared with those in patients treated by
the open chest method. There are many
pitfalls in making this comparison, since
factors other than the method of treatment
itself affect the recovery rate. A composite
picture of the salvage rate following open
chest cardiac massage is difficult to obtain,
because estimates of what constitutes
par-tial or complete recovery differ. The period
of time during which these patients were
followed varies with each report. The
re-sults are also affected by the location where
the cardiac arrest occurred, since with the
open chest method only an occasional
pa-tient survived cardiac arrest which was
di-agnosed and treated outside the operation
room. The reports specifying location
dem-onstrate the lower success rate of treatment
on the ward, in the x-ray room, tile
bronchos-copy room, the ambulance, the emergency
room, or other locations. Survival in five
rep-resentative series ranged from 14 to 29% in
the cases treated inside the operating room,
and from 0 to 21.1% in cases outside the
op-crating room.1113’18’19 These series include
both adults and children. The low survival
rates among these patients are a reflection of
the seriousness of their primary disease
processes, of delay in diagnosing arrest, of
further delay in opening the chest, and
of the adverse conditions under which most
of these cases had to be treated.
The poor results associated with
thoracot-omy in unpremeditated circumstances are
TABLE III
INCIDENCE OF CARDIAC ARREST IN CARDIAC SURGERY
Source Age Group Total (‘ases Cardiac Arrest From Cardiac Surgery Only Cases of Cardiac Surgery Incidence of
Arrest in Cardiac
307
counterbalanced somewhat by the serious
degenerative diseases of the heart now
being treated by tile closed method and in
which recovery rate is also
poor.2#{176}How-ever, the outstanding factor in survival
af-ten cardiac arrest, is the length of time
elapsed before an artificial circulation is
re-established. Stephenson et al.’ showed
that of the permanently resuscitated cases,
94% were massaged within 4 minutes of the
onset of arrest and that survival rate was
only 6% in the cases treated with a delay of
4 or more minutes. Co1e19 presented even
more striking evidence of tile importance
of the 4-minute limit. Of his 132 cases of
cardiac arrest, 33 patients recovered
com-pletely, and all had treatment started
with-in 4 minutes of diagnosis, a survival rate
of 42%. When tile treatment was started
after 4 minutes from the onset only two
patients survived (7%), and these showed
permanent central nervous system damage.
The authors pointed out that the
pre-exist-ing hypoxia in many cases of cardiac
an-rest may make this margin of safety even
smaller.
Series of cases of cardiac arrest in
chil-dren are listed in Table I. These results
vary from 11.5% complete and 7.7% partial
recovery to 50% complete recovery. Young
age does not seem to be a factor in
prog-nosis.11 However, one extensive survey15
re-vealed an adult survival rate of 50%,
corn-pared to the complete and partial recovery
rates of only 16% each, in patients up to the
age of 12.
Results of closed-chest cardiac
compres-sion are even less certain, since only two
sizable 222 have been reported, one
of these by the originators of the method.
Jude et al., in their last report of 118
pa-tients with 138 cardiac arrests, including
some cases previously 10
mdi-cated an over-all survival rate of 24% (28
patients). Seventy-five arrests were outside
of the operating room and recovery room.
Of these, 24 were inpatients with
myocan-dial infarction; the other 51 occurred in
association with miscellaneous diseases in
which hypoxia played a role. Thirteen per
cent of the patients with myocardial
in-fanction in whom resuscitation by external
cardiac massage was attempted were well
enough to be discharged; of the
miscehlane-ous group 7% recovered completely. In the
operating room, 35 arrests were associated
with general surgery and 28 were either
precardiac or postcardiac surgical patients.
Complete recoveries in both groups were
54% and 10% respectively. Ventricular
fibril-lation accounted for 30% of all cases, and
was treated by external defibrillator. These
results compare favourably with salvage
rates obtained by open chest massage,
es-pecially since the majority of cases
resusci-tated by compression took place outside of
the operating room and recovery room,
and involved patients with myocardial
in-fanction and other severe primary diseases.
In contrast, Baringen and associates21
re-ported that of 84 patients treated with
cx-ternal cardiac compression, only 4 survived
to leave the hospital, a salvage rate of 4.5%.
All but five cardiac arrests happened
out-side of the operating room, and most of the
patients suffered from severe or terminal
degenerative diseases. Nevertheless, at least
15 other patients were also resuscitated,
only to succumb a few days later to their
primary disease.
A direct comparison of the effectiveness
with which an artificial circulation can be
maintained by the open and closed
meth-ods of cardiac massage is posible only if the
same patient is treated with both
tech-niques. This has happened in a few cases
when, following external cardiac massage,
the chest was opened in order to arrest
yen-tnicular fibrillation with an internal
defibnil-lator. In these cases similar systolic
pres-sures were achieved by both methods.
Redding and Kozine22 studied the
rela-tive effectiveness of the open and closed
methods and also attempted to determine
what trauma could be associated with the
compression technique. In 20 dogs
weigh-ing between 6 and 12 kg they found that
the artificial circulation produced by closed
chest cardiac compression approximated
mas-sage, and the circulation was effectively
re-stored by either method. External cardiac
compression was found in these
experi-ments to be much less fatiguing to the
operator than direct massage.
Many reports record the aortic and
carot-id blood pressures achieved by external
cardiac 3 2224 Pressures up
to 200 mm Hg have been reached without
difficulty. Safan24 reported eight patients
with arterial blood pressures at 0 mm Hg,
or electrocardiograms showing ventricular
fibrillation or asystole, in whom during
closed-chest cardiac massage near normal
systolic blood pressures were recorded by
catheter and strain gauge, or the cuff
method. He also proved that cardiac
corn-pnession alone will not ventilate the lungs,
and that artificial respiration is as necessary
as artificial circulation in the treatment of
cardiac arrest.
COMPLICATIONS
Beside the advantages of external
car-diac compression its complications should
be considered. Because of the simplicity of
tile method and its use outside the hospital,
many lay persons will be attempting it.
Un-less compression is performed correctly,
several complications may anise. These can
be serious but are usually avoidable.
Though the condition of patients requiring
cardiac massage is often critical, and the
majority of deaths are caused by the
pri-mary disea1,e, the complications of
treat-ment contribute to this mortality. In the
pediatric age group, where primary
candio-vascular disease is rare, the salvage rate
could vell be higher if the complications of
massage were avoided.
Trauma following the application of
cx-tennal cardiac compression has been
men-tioned in several 20, 21, 25 These
complications are attributed to faulty use of
the method. One of the originators4 of the
method stated that “application of the
cx-tennal pressure in the proper location will
usually avert most side effects.” He
men-tioned fractured or cracked ribs as the most
common complication avoided by applying
pressure on the lower sternum only and not
on the ribs. He also listed two cases of
sub-capsular hematoma of the liver resulting
from pressure over the xyphoid or
epigas-tnium, and a fractured sternum from
place-ment of pressure near the sternal angle.
Only one fatal complication, probably due
to massive pressure, was found at
autopsy-a teautopsy-ar of the inferior vena cava in a
67-year-old woman with multiple pulmonary
in-farcts. Bone marrow emboli resulting from
rib fractures were found in the pulmonary
arteries in over 50% of the patients examined
post mortem. Besides fractured nibs, two
cases of ruptured liver and two cases of
major intrathonacic hemorrhage have been
reported by Safar in patients treated by
laymen. The report by Julian2#{176}describing
the results of external cardiac compression
in patients with myocardial infarction
shows how the effectiveness of the
tech-nique is lessened by inexperience and by
delay in starting treatment. In three of
five individuals treated by closed-chest
massage, the person who started the
mas-sage had not used the technique previously.
In three cases there were delays of 2 to 10
minutes before beginning the massage
through the open chest. Closed chest
corn-pression could have been started
immedi-ately. In all five cases 5 or more minutes
elapsed before artificial respiration was
ad-ministered. In one patient severe chest
in-juries were caused by application of
pnes-sure to the ribs, and in another an
made-quate blood pressure was maintained
be-cause the patient was on a soft bed. Most,
if not all, of these mishaps can be prevented
by awareness of the possibility of cardiac
arrest and prompt application of cardiac
compression with careful attention to
de-tails.
The importance of experience in the
prop-en application of the compression
tech-nique is also stressed by Baningen et al.21
in the only published statistical study of
complications. As personnel in their
hos-pital became more familiar with the
method, rib fractures were sharply reduced
with external cardiac compression, they
found two to eight ribs fractured in 15
cases, niarrow eml)oli in 6, various liver
in-juries in 5, Ilemothorax of 100 to 800 ml in
4, and ilemopenicardia of 50 to 100 ml in 2
cases. Despite these complications,
de-SCril)ed also with the open-chest method,7
the possibility of salvaging a “dead”
pa-tient outweighs the risk of trauma.
Since specific errors in the point of
ap-plication or the pressures required in cx-ternal cardiac compression are responsibile
for most of these injuries, the structure of
the thoracic cage in infants and young
chil-dren may expose this age group in
particu-lar to major trauma from compression of
the chest. In our experience, two children
aged 3 and 9 years, who underwent
pro-longed external cardiac compression in the
Emergency Department, llave been found
at post mortem to have extensive tears of
the liver (Fig. 4). In the first case, a
frac-tuned rib vth associated subpleunal,
inter-costal, and suhdiapiiragmatic hemorrhages
vas tlS() 1)r(se11t; ill the secotid, a large sub-capsular hematoma extended from tile edge
of the laceration. Both children had 800 to
1,000 ml of i)lO)d in the abdominal cavity.2s
In the experimental studies mentioned
previously,22 the authors noted that
mcdi-astinal hemorrhage, fractured ribs, and
lac-erations of the liver were encountered
fre-(juently when maximal forces were exerted.
When only moderate force was applied to
tile chest, trauma was minimal. This latter observation has special significance for the
pediatric age group since the
anteropos-tenor diameter of the chest and high lying
(hiaphragm of the dog approximates the
tlioracic dimensions of infants and very
young children. Rupture of the liver and
exsanguinating intraperitoneal llemorrhage
may result from forces applied below the
xyplioid process or on it. Pressure just
be-low the sternal notch vihl cause fracture of
the sternum, which cannot he depressed at
tiliS level. Sufficient pressure upon the ribs will result in rib fractures, marrow embohi
to the pulmonary arteries, and, if excessive,
in hemothorax.
FIG. 4. Tear tilrough the ngllt lobe of the liver. A Su1)erfiCial laceration underlying tile right costal
margin is also present.
Effective arterial blood pressure levels
can be maintained in children when the
compression is applied with the heel of
one hand only.4’2#{176}In the newborn infant,
systolic pressures exceeding 70 mm Hg
have been produced by compression with
the tips of two fingers. One of four infants
was resuscitated to normal status in this
manner.3#{176} Thus the danger of severe
inter-nal tears and ruptures of encapsulated
or-gans from excessive pressure in minimized.
The procedure should result in easily
paip-able femoral pulses or, when followed on a
sphygmomanometer attached to the upper
arm of the patient, in blood pressures of 90
to 120 mm Hg. These effective levels can
be achieved without difficulty or danger in
children whose hearts have stopped.
SUMMARY
External cardiac compression is now the
accepted method of treating sudden cardiac
arrest. The technique is described, with
particular emphasis on the steps which can
cause serious trauma, if not properly
per-formed. Ventilation of the lungs is of
pana-mount importance.
The incidence of cardiac arrest seems to
be increasing and appears to be higher in
infants, perhaps because of the large
pro-portion of cardiac surgical procedures in
this age group. Survivals depend on several
factors, the most important of which are
the time elapsed before treatment is begun,
cardiac arrest, and the primary disease of
the patient. Use of external cardiac
compres-sion diminishes delay, makes the location of
the patient less important, and produces less
trauma
in a
critically ill patient. Bloodpres-sunes achieved by the external method are
comparable to levels reached by direct
mas-sage of the heart. The myocardium is not
traumatized by the external method, which
is also less fatiguing to the operator.
The complications of external cardiac
compression are traceable to excessive
pres-sures and to pressure over wrong areas of
the chest, and are therefore avoidable.
Pres-sure should be applied to the sternum in
the mid-line only, just above the xyphoid
process. Two cases of ruptured liver in
children are mentioned, and reports of
other injuries are discussed in connection
with specific errors in technique.
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