Major Extracorporeal Perfusion
Circulation of blood through an artificial circuit containing a:
- Pump for assisting circulation
- (Usually) a mechanism for exchange of oxygen and carbon dioxide
Organisation of Service
A hospital providing major extracorporeal perfusion should have:
- A Head of service
- Responsible for administration and delivery
- Usually a cardiac anaesthetist or cardiac surgeon
- Appropriate staffing
- Appropriate equipment
- Dedicated space
- Easy access to operating theatres and intensive care unit
- Storage of hardware and disposables
- Appropriate training
- Managing patient on bypass
- Administration of medication
- Assembly and operation of bypass equipment
- For anaesthetic trainees training as medical perfusionists, requirements include:
- At least 12 months
- 75 perfusions
The first 50 cases should be closely supervised.
- Critical scenarios including:
- Pump head failure
- Gas in the circuit
- Oxygenator changeout
- Maintenance
- At least 40 cases per year
Equipment
Heart-lung machine should:
- Meet electrical standards
- Undergo routine inspection and maintenance
- Include:
- Pump heads
- 3 or more available
- Alarms
- Servo-controlled mechanisms
- Manual override capability
In the setting of:- Low blood resevoir
- Arterial over-pressure
- Bubble detection
- Runaway control protection
- Display of flow
In L/min or RPM. - Easily calibrated
- Cranking system
- Transparent removable covers
- Gas supply
- Connect to an indexed piped medical gas system
- Alarms
- Emergency oxygen supply
- Gas flow meters and gas blenders
- Oxygen analyser
Either on:- Oxygenator gas supply line
- Oxygenator effluent gas
- Scavenger
If volatile agents in use.
- Heat exchanger
- May be external or self-contained water supply
- Water between:
- 4 and 42°C
- 10 and 25 L/min
- Not at pressures ≥600mmHg
- May be external or self-contained water supply
- Monitoring and alarms
Appropriately positioned, maintained, and calibrated.- Low-level detection monitor
Detects when the blood resevoir runs low. - Arterial line pressure monitor
- Pre- and post-membrane pressure monitor
- Gas-emboli detector
- Venous saturation
- Low-level detection monitor
- Pump heads
Clinical Management
Involves:
- Assembly, checking, and priming of the ECP circuit
- Completion of pre-bypass checklist
- Exclusive availability of the perfusionist for that patient
- Assessment and documentation of coagulation status
- Continuous assessment of physiology and coagulation during ECP
- Appropriate flows, perfusion pressures, gas exchange, and acid-base homeostasis
- Consideration of co-morbid disease
- Appropriate contemporaneous documentation