1. Updates in Trauma – REBOA and SAAP
GSA HEMS Wollongong CGD
August 13th

2. 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)

3. 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

4. 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.

5. 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)

7. 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

8. 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 mL. Inflate the balloon with saline and contrast agent.

11. Secure Everything for Transport

14. 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.

16. 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

17. 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.

18. 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.

19. 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.

20. 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.

22. 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 reperfusion- induced injury.

23. 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 mmHg.

24. 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

25. 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.

26. 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.

27. 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)

30. 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.

31. 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.

32. References REBOA review article REBOA case series SAAP
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