Echocardiography in Intensive Care

OVERVIEW

Echocardiography in Intensive Care allows direct visualisation of the heart, vessels and pleura

INDICATIONS

Assessment of:

• preload
• ventricular function
• afterload
• valvular function
• aortic dissection
• pericardial disease

American College of Cardiology Guidelines for ECHO in the Critically Ill

Category I (useful and effective)

• haemodynamically instability
• suspected aortic dissection or aortic injury
• multiple trauma
• chest trauma

Category II (may be beneficial)

• cardiac output monitoring

Category III (unlikely to benefit and may cause harm)

• the haemodynamically stable with no abnormal findings or cardiac disease

ARGUMENTS FOR

• can obtain adequate TTE image in most mechanically ventilated patients
• information gathered can change management
• intensivists more readily available and can perform repeated examinations
• cardiologists not used to assessment of the critically ill (effect of therapeutic interventions, inotropes, fluid therapy, IABP)
• saving images allows review, audit, governance and quality control.

ARGUMENTS AGAINST

• steep learning curve (written assessment + a log book of 250 ECHO’s recommended by British Society of Echocardiography)
• requires structured training (just picking up probe can mean drawing wrong conclusions)
• cardiologists provide more comprehensive assessment

TYPES

(1) Trans-thoracic echo (TTE)

Advantages

• quick, easy
• non-invasive
• no contraindications
• no morbidity or mortality
• useful in seeing LV clot and pericardial effusion

Disadvantages

• limited windows in ventilated
• limited usefulness in endocarditis

(2) Transoesophageal echo (TOE)

Advantages

• minimal morbidity and mortality
• excellent images
• good in ventilated patients
• required in endocarditis and LA clot diagnosis
• very useful for pericardial effusion and LV function
• correlates well with PA catheter
• less invasive than PA catheter
• safe with diathermy

Disadvantages

• take more time
• requires sedation
• oesophageal pathology = contraindication
• bacteraemia
• ulcers
• aspiration

CONCLUSION

• ECHO allows improved assessment and management of unstable, critically ill patients
• essential tool for category I indications
• continued cardiology input essential to maintain safety

References and Links

• Briggs, J et al (2010) “Should echocardiography become a core skill for intensivists?” British Journal of Hospital Medicine, Vol 72(1) page 58