Basic components of IABP: Hardware; disposals

1. Catheters

a) Catheter length

i) Approximate length of catheter required for optimal placement in descending aorta estimated by placing the tip of the catheter approximately 1 cm below the sternal angle of Louis before insertion

b) Balloon size

i) Balloon capacities range from 20cc to 40cc

ii) The more blood displaced during diastole, the better the augmentation

iii) Avoid totally occluding aorta

a) Aorta intimal damage

b) Haemolysis

iv) Optimal 85% of aorta occluded

v) Determined by size of:

a) Femoral artery

b) Patient

c) Catheter size

i) Newer, small diameter (10.5F & 9.5F) catheters have a decreased incidence of complications (19%) versus the larger (12F) devices (32%)

ii) RNSH

a) 40 cc: 9.5 Fr

b) 34 cc: 8.5 Fr

d) Catheter type

i) Single chamber

a) Lumen simply for gas to inflate/deflate balloon

b) Reserved for severe PVD &/or small patient

c) Reduced complication of leg ischaemia

ii) Dual chamber

a) Additional lumen for ease in insertion (over guide wire) and monitoring aortic pressures (increased accuracy in timing)

e) Catheter material

i) Copolymer of urethane & silicon

ii) Resilient & nonthrombogenic

2. Hardware

a) IABP console

i) Consists of a pressurised gas reservoir that is connected to the balloon supply line through a solenoid valve that is electronically controlled

3. Disposables

a) Drive line

b) Catheter

c) Can have a separate introduction kit

d) Transducers system

Balloon types; Inflation gases; Timing devices; Safety devices -emergency power & gases

1. Gases

a) Carbon dioxide

i) Dense & therefore slow to inflate & deflate balloon

a) Requires a larger diameter drive line with increased injury to artery

ii) Rapidly dissolved in blood if accidentally introduced

b) Helium

i) Low density [therefore reduced Reynold’s number] & therefore able to rapidly inflate & deflate balloon

a) Requires only a narrow diameter drive line

ii) Source of emboli if accidentally introduced into blood

a) Helium in volumes used in the IABP (20-40 ml) released into the descending aorta is promptly distributed to the cerebral & coronary vessels & is rapidly fatal

2. Battery backup [DataScope]

a) Datascope approx 50 minutes (takes 16 hours to fully charge)

3. Timing

a) Most are automatically timed with timing only having a minor influence - occasional use manual override (gross control) as sometimes parameters of timing fall outside automatic mode parameters

4. Balloon volume

a) Start half flow - organise timing - crank up to an ideal augmented pressure - care with little patients

5. Safety devices

a) Safety chamber

i) to hold blood to prevent entering hydraulics

b) Hydrophobic filter (datascope 96)

i) to prevent blood entering hydraulics

c) Disconnection alarm

d) Depressurising alarm

e) Insufficient inflation alarm

f) Gas alarm (20 more fills available)