Updates in Trauma – REBOA and
SAAP
GSA HEMS Wollongong CGD
August 13th
REBOA
• Resuscitative Endovascular Balloon Occlusion
of the Aorta.
• First described in 1954 in the Korean War.
• Haemorrhage control below the level of the
chest without having to do an open procedure
(thoracotomy with aortic cross clamping)
REBOA
• Simple procedure – gain arterial access and
insert a balloon into the aorta and inflate to
control bleeding.
• Endovascular procedure – vascular surgeons
having been using techniques like REBOA for
the last 20 years for ruptured AAA
REBOA
• Now has expanded into the areas of trauma
and hemorrhagic shock.
• Used as a bridge in haemodynamically
unstable patients to theatre or interventional
radiology.
REBOA - Technique
• Gain access to the CFA (avoid the SFA as this is too
weak to hold a dilator and will rupture)
• Most common site is the right CFA
• Best level to access the CFA is at the inguinal crease
• In cardiac arrest, open procedure is preferred to
percutaneous approach due to difficulty in cannulating
femoral artery in cardiac arrest (alternatively can use
ultrasound approach)
REBOA - Technique
• Float the wire
– Measure externally to the level of the umbilicus
and the second rib
– Advance wire to the measured depth
– Confirm placement with X-Ray
• Place sheath (12F) – will require a dilator
REBOA - Technique
• Float the balloon, measure externally first;
– Zone 1 is to the level of the xiphoid
– Zone 3 is to the level of the umbilicus
• Inflate the balloon until there is moderate
resistance - no set pressure determined as yet.
This is dependent on the size of the patient but
averages between 12-24 mL. Inflate the balloon
with saline and contrast agent.
Secure Everything for Transport
When to use REBOA
Patients who arrive recently dead
Patients who are actively trying to die
Patients with injuries making them prone to try
to die.
REBOA
• Once arterial access is gained, time for
insertion is usually less than 5 minutes
(average is 90 seconds)
• Duration of inflation (based on experimental
animal models)
– Zone 1; 1.5 hours
– Zone 3; 5 hours
REBOA - Effectiveness
• Literature limited to case reports currently.
• On average the blood pressure increased by
55 mmHg when REBOA was used in one case
series.
• In the other case series of 13 patients, the
blood pressure increased from 41 +/- 26 to
111 +/- 47 mmHg.
REBOA - Prehospital
• London’s HEMS performs the worlds first
prehospital REBOA in July of this year.
• Plans for Sydney HEMS to start using
technology in the next few years.
SAAP
• Selective aortic arch perfusion (SAAP) is an
experimental resuscitative intervention that
involves the placement of a large-lumen
balloon occlusion catheter in the descending
thoracic aorta via a femoral artery.
• Allows relatively isolated perfusion of the
heart and brain – useful in resuscitation from
medical and traumatic cardiac arrest.
SAAP
• It differs from REBOA in that the catheter has
ports for infusing oxygen carrying fluids and
vasoactive drugs.
• Inflation of the balloon serves as a functional
aortic cross- clamp and provides for relatively
isolated perfusion of the heart and brain with
an oxygen-carrying perfusate.
SAAP
• Oxygen carrying fluids include;
– Haemoglobin based oxygen carrier (HBOC)
– Fluorocarbon based carriers (PFC)
– Blood (current prototype)
• SAAP also can be used to deliver metabolic
substrates, vasoactive drugs, and agents to
limit ischemic damage and reperfusioninduced injury.
SAAP
• Involves insertion of femoral sheath into
femoral artery.
• Catheter is slightly larger than the CODA
balloon used with REBOA to allow for
perfusion and administration of vasoactive
drugs.
• Balloon inflated to pressure of 150-180
mmHg.
SAAP
• Blood is infused at 10 ml/kg/min
– 750 mL/min (3 units of blood per minute)
– Infuse for up to 3 minutes in medical cardiac
arrest without volume overload.
• Get venous access at the same time
– Allows you to pull off blood
– Limited body ECMO
SAAP
• Infuse vasoactive drugs directly to heart and
brain
– Results in improved ROSC
– Intra-aortic adrenaline has minor effect on
coronary and cerebral vasculature. Thought to
shunt blood by vasoconstriction from upper limbs
to heart and brain.
– IA Adrenaline dose is 1/3 of normal.
SAAP - Trauma
• Feasible to float the balloon in the field
blindly.
• Balloon works as a functional cross clamp and
allows selective perfusion of heart and brain.
• Allows volume replacement
• Next step following a failed REBOA procedure.
EPR – Emergency Preservation &
Resuscitation
• Suspended Animation
• Induced hypothermia – cold saline infused to
core temperature of 10 degrees.
• Vital surgery performed to repair injury and
then patient rewarmed on heart-lung bypass
machine
• Estimated downtime of 4 hours
• ER-CAT trial starting with 10 patients
(penetrating trauma)
Summary - REBOA
• Balloon occlusion of the aorta – equivalent to
cross clamping aorta
• Effective in haemorrhagic shock as a bridge to
definitive therapy.
• Has been used clinically in vascular surgery for
the last 20 years – recent expansion into other
areas including trauma
• Planned introduction into NSW prehospital
system soon.
Summary - SAAP
• Experimental procedure with inflation of
balloon in descending aorta.
• Allows selective perfusion and oxygenation of
heart and brain.
• Allows administration of O2 carrying fluid and
vasoactive drugs directly to brain and heart.
• Proposed next step following failed REBOA.
References
• REBOA review article
– J Trauma. 2011; 71(6);1869
• REBOA case series
– J Trauma. 2010; 68(4);942
– J Trauma Acute Care Surg. 2013;75(3);506
• SAAP
– Critical Care Med. 2001;29(11);2067