ECMOBoot Camp Basics

Will Costello, MD

ECMO PUMP

• Centifugal

• Flow dependent on resistance, so minimize drugs that cause vasoconstriction, anxiety.

V-A ECMO

V-V ECMO

Indications (VV)

• PF ratio <60 or PF ratio <100 with PaCO2 100mmHg for >1 hour despite maximal therapy

• Common

• Severe pneumonia

• ARDS

• Pulmonary contusion

• Severe hypoxemia following cardiopulmonary bypass

• Acute graft failure following lung transplant

•

• Other:

• Alveolar proteinosis

• Smoke inhalation

• Status asthmaticus

• Airway obstruction

Indications (VA)

• Common:

• Cardiogenic shock: AMI and complications (including: wall rupture, papillary muscle rupture, refractory VT / VF) refractory to conventional therapy including IABP

• Post cardiac surgery: unable to wean safely from cardiopulmonary bypass using conventional supports

• Drug overdose with profound cardiac depression – local anesthetic toxicity, beta blocker overdose

• Myocarditis

• Early graft failure: post heart / heart-lung transplant

• Idiopathic acute heart failure as a bridge to decision

Indications (VA) cont’d

• Other

• Pulmonary embolism

• Cardiac or major vessel trauma

• Massive hemoptysis / pulmonary hemorrhage with known etiology

• Pulmonary trauma

• Acute anaphylaxis

• Peri-partum cardiomyopathy

• Sepsis with profound cardiac depression

• Bridge to transplant

Contraindications

• Absolute Contraindications to all forms of ECMO • Age > 70 yrs

• Non-recoverable cardiac disease and not a VAD/TX candidate

• Non-recoverable respiratory disease

• Non-recoverable neurological disease or intracranial hemorrhage within the previous 6 months

• Chronic severe pulmonary hypertension

• Active malignancy, graft vs host disease or significant immunosuppression

• Post bone marrow, renal, liver transplant

• Advanced liver disease Childs class C not undergoing transplant

• AIDS as defined by: • Secondary malignancy, prior hepatic or renal (Crt > 250umol/l)

• impairment or need for salvage anti-retroviral therapy

• Un-witnessed cardiac arrest or CPR > 60min prior to commencement of ECMO (this includes set up - cannulation time)

• Pulmonary /alveolar hemorrhage

Contraindications

• Relative Contraindications to all forms of ECMO • Trauma with multiple bleeding sites

• Multiple organ failure

• Absolute Contraindications to VV ECMO for Respiratory Failure

• Severe right or left heart failure (LVEF< 25%)

• Cardiac arrest

• Absolute Contraindications to VA ECMO

• Aortic dissection Severe aortic valve regurgitation

Evidence

• First trials in adults in 1970s. No improvement in long term outcomes, with multiple methodological problems (No lung rest)

• Use in adults limited to select centers through the 90s.

• Published data for adults still limited, but improving

• U of M registry with 56% survival rate in 146 adults with respiratory failure, 33% survival in 31 adults with cardiac failure

CESAR

RR of death or permanent disability 0.69 with P=0.03 in 180 patient RCT for severe ARDS (H1N1)

ELSO registry

• Of 1,473 patients, 50% survived to discharge.

• Median age was 34 years.

• (78%) were supported with venovenous ECMO.

• CPR and complications while on ECMO including circuit rupture, central nervous system infarction or hemorrhage, gastrointestinal or pulmonary hemorrhage, and arterial blood pH < 7.2 or >7.6 were associated with increased odds of death.

Management

• Anticoagulation

• Patients on ECMO must be anticoagulated with heparin or a direct Xa inhibitor. Anticoagulation monitored closely with hepassay, ACT, or PTT determined by ECMO intensivist

• Can be held for short periods of time in the setting of uncontrolled hemorrhage

• Bleeding complications (CVA, retroperitoneal hemorrhage, anemia) common, so vigilance is required

Management

• Lung rest

• Crucial to effectiveness of therapy, particularly when on VV.

• Peak pressures under 20 cm H2O

• TV often too small to prevent alarms. Work with RT to find solution (flows added to circuit to confuse vent)

• Can extubate if neuro allows for pulmonary toilet, maintenance of airway.

• Infection

• Difficult to diagnose

• Circuit can cause SIRS

• Fluid warmer maintains central temp wnl

• Serum markers often used (CRP, procalcitonin)

Management

• Mechanical problems

• Frequently a true emergency

• Damage to circuit: may require emergent replacement of circuit

• Call for help

• Consider returning vent to pressures necessary for temporary support

• May require support with high dose inotropes, pressors until flow re-established

• Thrombosis, air lock, pump failure

• Be prepared to provide support to ECMO specialist, perfusion

• Critical Illness

• Most important: is still a critically ill patient. Excellent ICU care will play as important a role in recovery as ECMO. Be vigilant, precise.

` Management

• Monitors

• Pre and post pump pressure monitors.

• Typical pre pump <100mmHg, but no absolute number

• Trend upward raises concern for hypovolemia, thrombosis

• Post pump <350 mmHg, but also trend is more important

• Sharp increases can indicate kinked cannula, problems with site, thombosis

• ABGs

• Usually done at least Q2 Hrs early on

• Goal pH 7.35-7.45, regardless of PaCO2

• PaO2 drawn form RUE on VA to assure brain oxygenation

• Often low PaO2 due to mixing, but OK if clearing lactate

Questions?