In a 2018 article published in the ICU: Management & Practise section of HealthMangement.org, Drs. Adrian Wong and Jonathan Wilkinson discussed the benefits of deploying point-of-care ultrasound for patients in various forms of shock. They conclude that POCUS can help the clinician to more accurately identify the type of shock, or the coexistence of different types of shock. With proper target management strategies, ultrasound is an invaluable tool for emergency physicians and intensivists.
Shock is a common enough occurrence in the ED and ICU, and can co-exist in different forms. The authors point out the example of a septic patient who is in shock due to distributive/vasodilatatory shock or cardiogenic shock. They focus on the key modules in the diagnosis and management of shock with the examination of the cardiovascular and respiratory systems.
Using POCUS with an Integrated Approach
For heart and lung examinations, POCUS can help answer the following key questions:
- Is the left ventricle (LV) dilated or impaired?
- Is the right ventricle (RV) dilated or impaired?
- Is the inferior vena cava (IVC) collapsing?
- Is there a pericardial effusion?
- Is/are there pleural effusion(s)?
The Rapid Ultrasound for Shock and Hypotension (RUSH) protocol allows emergency physicians to carry out a structured ultrasound examination in under two minutes. RUSH requires an examination of the heart, intravascular filling status, and large arteries/veins.1 Another POCUS-based protocol is SESAME (abbreviated from SESAMOOSIC Sequential Echographic Scanning Assessing Mechanism or Origin of Shock of Indistinct Cause) and the Abdominal and Cardiothoracic Evaluation with Sonography in Shock (ACES) protocols.2 These integrated approaches form a significant part of most POCUS practise in emergency medicine and critical care.
Once only used to diagnose pleural effusions, POCUS for lungs has now expanded into many other applications. A recent review and meta-analysis concluded that lung ultrasound was superior to chest radiographs in terms of sensitivity, with similar specificity.3
POCUS in daily practise
The authors emphasise that POCUS, like any other monitoring device, must be paired with a management strategy. Ultimately, different ICUs will adopt different management strategies based on their staffing, working shift patterns, experience and availability of POCUS practitioners, number of ICU/ high dependency unit beds, workload, and ready access to a suitable ultrasound machine.
Image acquisition is only one part of the ability to make the diagnosis and formulate a management plan. Image interpretation is an essential part of the training process and competency assessment. Artificial Intelligence (AI) is also beginning to become an integrated part of health care. AI can be used to interpret scans for signs of malignancies. These AI systems, however, are meant to aid and not replace the human clinician.
Read the full study with statistical charts and references here.
References
1Perera P, Mailhot T, Riley D et al. (2010) The RUSH Exam: Rapid Ultrasound in SHock in the evaluation of the critically ill. Emerg Med Clin N Am, 28: 29–56.
2Lichtenstein D, Malbrain ML (2015) Critical care ultrasound in cardiac arrest. Technological requirements for performing the SESAME-protocol--a holistic approach. Anaesthesiol Intensive Ther, 47(5): 471-81.
3Winkler M, Tuow H, van de Ven P et al. (2018) Diagnostic accuracy of chest radiograph, and when concomitantly studied lung ultrasound, in critically ill patients with respiratory symptoms: a systematic review and meta-analysis. Crit Care Med, 46(7): e707-e714.