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Once control is achieved
and cardiac activity restored, the patient is transferred
rapidly to the operating room for defintive management.
Equipment:
| Approach: |
|
| Scalpel with 10 blade |
|
| Curved Mayo scissors |
|
| Rib spreader |
|
| Gigli saw or large 'trauma'
shears |
|
| |
|
| Haemorrhage control: |
|
| McIndoe / Metzenbaum scissors |
3/0 non-absorbable suture (nylon,
polypropene) on round-bodied needles - multiple |
| DeBakey vascular forceps (long) |
2/0 absorbable ties (vicryl,
pds etc) - multiple |
| DeBakey aortic clamp |
Laparotomy packs |
| Satinsky vascular clamp (large
& small) |
Teflon pledgets - small. (10) |
| Mosquito / Dunhill artery clips
(10) |
|
| Long & short needle holders |
|
| |
|
| High volume, high-displacement
suction |
|
| |
|
Approach
A supine anterolateral thoracotomy is
the accepted approach for emergency department thoracotomy.
A left sided approach is used in all patients in traumatic
arrest and with injuries to the left chest. Patients
who are not arrested but with profound hypotension
and right sided injuries have their right chest opened
first.
In both cases it may become necessary
to extend the incision across the sternum to aid access
and vision. With a right sided thoracotomy, the left
chest will have to be opened if internal cardiac massage
becomes necessary.
Gaining access to the thoracic cavity
should take no more than 1-2 minutes. After rapid
skin preparation with large antiseptic-soaked swabs,
a skin incision is made in the 5th intercostal space
from the border of the sternum to the mid-axillary
line. This is continued down through subcutaneous
tissues to reach the intercostal musculature.
The intercostal muscles are incised
with a combination of scalpel, heavy scissors and
blunt dissection. Take care not to lacerate the lung
at this stage. Insert the rib spreaders between the
ribs and open.
If the thoracotomy has to be extended
to the other side of the chest, repeat the thoracotomy
on the other side. To divide the sternum, a large
pair of trauma shears (as used to cut the clothes
off patients) will easily go through the sternum.
Otherwise the Gigli saw is used to divide the sternum.
The first time you see a Gigli saw should not be the
first time you perform a thoracotomy. Examine one
to see how it is put together and practice the action
needed to saw through bone. Once through the sternum
the rib spreader is moved to the midline to open the
chest at the sternum.
Division of the sternum results in transection
of the internal mammary arteries. These will start
to bleed once blood pressure is restored and will
need clipping and ligation subsequently.
Relief of tamponade
The pericardium is opened longitudinally
to avoid damage to the phrenic nerve, which runs along
its lateral border. It is difficult to visualise the
phrenic nerve in the emergency thoracotomy. Make a
small incision inthe pericardium with scissors and
then tear the pericardium longitunidally with your
fingers - this will avoid lacerating the phrenic nerve.
Evacuate any blood and clot from the pericardial cavity.
Control of haemorrhage
Cardiac wounds
Cardiac wounds should
be controlled initially with direct finger pressure.
Large wounds may be controlled temporarily by the insertion
of a foley catheter with inflation of the balloon. The
balloon may obstruct inflow or outflow tracts however
and it may also lead to extension of the laceration
if excessive traction is placed on it. Satinsky clamps
can be placed across wounds of the atria to control
haemorrhage. With extensive cardiac damage it may be
necessary to temporarily obstruct venous inflow to allow
repair. Take care also not to miss posterior cardiac
wounds. Examination of the posterior surface of the
heart requires displacing it anteriorly, which may obstruct
venous inflow.
 
Cardiac wounds can be
directly sutured using non-absorbable 3/0 sutures such
as nylon or polypropene. Bypass is unnecessary, even
in the beating heart. Teflon pledgets are unnecessary
in the left ventricle but, if available, may be used
in the right ventricle. With wounds in the region of
the coronary vessels, mattress sutures are used to avoid
obstructing coronary flow. Atrial wounds are sutured
using a continuous technique.
Pulmonary & Hilar
injuries.
Massive haemorrhage from
the lung or pulmonary hilum can be temporarily controlled
with finger pressure at the pulmonary hilum. This may
be augmented by placement of a Satinsky clamp across
the hilum. This can however cause laceration of the
pulmonary veins when used emergently by the inexperienced
surgeon. An alternative is to tie off the pulmonary
hilum using tracheal tube tie or tape from a laparotomy
pack.
Acute occlusion of the
pulmonary hilum often leads to immediate acute right
heart failure, especially in the young fit adult. This
needs to be recognised early and managed with only partial
or intermittent occlusion of the pulmonary hilum.
Lesser haemorrhage from
the lung parenchymas can be controlled with a temporary
clamp.
Great vessel injuries.
Small aortic injuries
can be sutured directly using the 3/0 non-absorbable
suture. Larger injuries, especially to the arch may
require temporary digital occlusion and insitution of
cardiac bypass.
Access to the vascular
structures of the superior mediastinum is difficult
with an anterolateral thoracotomy. The sternum may have
to be split in the midline and/or a supraclavicular
incision used to control haemorrhage from subclavian
and innominate vessels. Again, control is achieved temporarily
with digital pressure or proximal & distal clamp
application prior to defintive repair.
Internal cardiac massage
In traumatic arrest,
internal cardiac massage should be started as soon as
possible following relief of tamponade and control of
cardiac haemorrhage. A two-handed technique produces
a better cardiac output and avoids the low risk of cardiac
perforation with the one-handed manoeuver.
Aortic cross-clamping
Cross-clamping of the
descending thoracic aorta is used routinely in some
centres and not at all in others during emergency thoracotomy.
The rationale for clamping the aorta is to redistribute
blood flow to the coronary vessels, lungs and brain,
to reduce exsanguination from injuries in the lower
torso.
The efficacy of the aortic
cross clamp in improving perfusion of the coronary arteries
and brain is unclear however. Over-zealous fluid replacement
with the aortic clamp in place may lead to a significant
rise in afterload and precipitate cardiac failure.Organs
distal to the clamp will become ischaemic and this includes
the spinal cord when the clamp is placed higher, at
the aortic isthmus. Clamp time should ideally be 30
minutes or less. On removal of the clamp there is reperfusion
of the ischaemic lower torso, and products of anaerobic
metabolism and activated inflammatory mediators are
released back into the system. This may lead to myocardial
depression and subsequent systemic inflammatory response
syndrome.
Cross-clamping of the
descending thoracic aorta should possibly be reserved
for patients with potential exsanguinating injuries
to the distal torso.
Cross-clamping is done
ideally at the level of the diaphragm, to maximise spinal
cord perfusion. Otherwise just below the left pulmonary
hilum. The lung is retracted anteriorly and the mediastinal
pleura incised. Blunt disection is used to separate
the aorta from the oesophagus and prevertebral fascia.
This dissection should be enough to place a clamp across
the aorta but not complete, to avoid avulsing aortic
branches supplying the cord and thorax.
Karim
Brohi, trauma.org 6:6, June 2001
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