Frequently Asked Questions

Critical Care Ultrasound (CCUS) is a term that applies to a diverse array of applications from focused echocardiography to lung ultrasound to procedural guidance (1,2,3). Guidelines and expert consensus documents have emerged that advocate for critical care medicine training programs across North American to establish CCUS training programs, adopt training standards and develop mechanisms for quality assurance (1,2,3).

The goal of CCUS is not to supplant modalities such as comprehensive echocardiography or abdominal ultrasonography, but to provide a new skill set to acute-care physicians and other allied health care providers alike that can facilitate urgent decisions at the bedside and improve patient safety. Internationally, we have seen the critical care community engaging in CCUS from research to education for the benefit of democratization of this innovative technology.


How does CCUS compare to conventional diagnostic imaging modalities, including comprehensive echocardiography?

CCUS and comprehensive ultrasound should be viewed as complimentary modalities in the care of the critically ill patient. CCUS is most often performed by acute care physicians at the bedside and is goal-directed, performed in the context of immediate and time-sensitive decision making. Ultrasound modalities such as comprehensive echocardiography and abdominal ultrasound are also essential; however, urgent access around the clock may be limited, constrained by resources and frequently requires patient transport.

CCUS empowers acute care physicians with the ability to confront dilemmas that are beyond the realm of bedside examination and at times, conventional radiographs. One example of CCUS is thoracic ultrasound, a non-invasive technique that has demonstrated superiority to chest x-rays in identification of parenchymal and pleural pathology (4,5). Furthermore, modalities such as basic critical care echocardiography can be taught in an accelerated fashion with favorable inter-rater reliability (6,7). CCUS modalities such as focused echocardiography (6,8,9) and lung ultrasound, have demonstrated the ability to reduce the differential diagnosis, improve the time to diagnosis and frequently lead to changes in management (9,10). These are only a select few of a diverse array of CCUS applications.

What are the primary indications for CCUS?

  1. Undifferentiated hypotension or hemodynamic instability
  2. Undifferentiated respiratory failure and thoracic pathology (ie. effusions, consolidation).
  3. Volume status assessment
  4. Procedural guidance including paracentesis, thoracentesis and vascular access
  5. Detection of intra-abdominal free fluid including ascites, hemoperitoneum, etc.
  6. Undifferentiated sepsis and septic shock (i.e. pneumonia, acute cholecystitis).


What are the primary modalities of CCUS?

  1. Focused echocardiography including IVC assessment
  2. Thoracic ultrasound (pleural, parenchymal, pleural space)
  3. Integrated cardiac-lung assessment
  4. Focused abdominal ultrasound (free fluid, kidneys, bladder, aorta, gallbladder)
  5. Procedural guidance (thoracentesis, paracentesis)
  6. Vascular access (Central/peripheral lines) and assessment (for VTE)


References

  1. Mayo PH. American College of Chest Physicians Statement on Competence in Critical Care Ultrasonography. CHEST J. 2009;135(4):1050.
  2. Mayo PH. American College of Chest Physicians Statement on Competence in Critical Care Ultrasonography. CHEST J. 2009;135(4):1050.
  3. Arntfield RT, Millington SJ, Ainsworth CD, et al. Canadian recommendations for critical care ultrasound training and competency. 2014;21(6):341-345.
  4. Xirouchaki N, Magkanas E, Vaporidi K, et al. Lung ultrasound in critically ill patients: Comparison with bedside chest radiography. Intensive Care Med. 2011;37:1488-1493.
  5. Lichtenstein D, Goldstein I, Mourgeon E, Cluzel P, Ph D. Comparative Diagnostic Performances of Auscultation , Chest Radiography , and Lung Ultrasonography in Acute. 2004;(1):9-15.
  6. Vignon P, Chastagner C, François B, et al. Diagnostic ability of hand-held echocardiography in ventilated critically ill patients. Crit Care. 2003;7(5):R84-R91.
  7. Vignon P, Mücke F, Bellec F, et al. Basic critical care echocardiography: validation of a curriculum dedicated to noncardiologist residents. Crit Care Med. 2011;39:636-642.
  8. Stanko LK, Jacobsohn E, Tam JW, De Wet CJ, Avidan M. Transthoracic echocardiography: Impact on diagnosis and management in tertiary care intensive care units. Anaesth Intensive Care. 2005;33(4):492-496.
  9. Kanji HD, McCallum J, Sirounis D, MacRedmond R, Moss R, Boyd JH. Limited echocardiography-guided therapy in subacute shock is associated with change in management and improved outcomes. J Crit Care. 2014;29(5):700-705.
  10. Jones AE, Tayal VS, Sullivan DM, Kline J a. Randomized, controlled trial of immediate versus delayed goal-directed ultrasound to identify the cause of nontraumatic hypotension in emergency department patients. Crit Care Med. 2004;32(8):1703-1708.