Governance in point-of-care ultrasound

The performance and interpretation of ultrasound examination are very user-dependent that require significant training and experience. This chapter details the processes that should be adopted within an intensive care unit using point-of-care ultrasound to ensure that practitioners are appropriately trained and are able to maintain and develop their skills. The chapter also outlines recommendations regarding good practice in reporting and image storage, together with guidance regarding equipment management, to ensure patient safety.

Haemodynamic instability

This chapter will discuss how two-dimensional echo can be used to evaluate ventricular performance in terms of preload (volume status), systolic function (pump status), and filling pressure (pressure status). Using these parameters, it will describe an integrative approach to haemodynamic assessment that categorizes the patient into one of seven characteristic states that become immediately recognizable. It will also present useful practical tips on using echo in clinical practice and avoiding its pitfalls.

Abdominal assessment

The role of focused abdominal scanning includes its use during the initial assessment of severe trauma and to guide safe drainage of ascites. Knowledge of the normal abdominal appearance is essential for the safe interpretation of focused abdominal scanning. Assessment of the sub-diaphragmatic structures is also integral to undertaking lung ultrasound. This chapter describes the technique of abdominal scanning, the ultrasonographic features of the major intra-abdominal organs, and the appearances of some common pathology.

Aortic assessment

Imaging the aorta is an advanced skill, although important pathology may be identified by the critical care sonographer when undertaking focused transthoracic echocardiography and basic abdominal ultrasound. This chapter outlines the appearances of the normal aorta in focused echocardiography and abdominal ultrasound. The ultrasonic appearances of an aortic aneurysm and dissection are described.

Transoesophageal echocardiography, sonoanatomy, and standard views

This chapter will describe the omniplane probe (with its scan planes) and indications, contraindications, and complications of transoesophageal echocardiography (TOE), before defining a scheme for focused TOE assessment in a critically ill patient. It will highlight the cardiac structures that are best imaged using either transthoracic echocardiography or TOE, and outline specific clinical applications (including suspected aortic dissection, left atrial appendage thrombus, mitral disease, and right ventricular failure) that lend themselves to TOE assessment.

Transthoracic echocardiography, sonoanatomy, and standard views

This chapter will describe all the standard focused cardiac ultrasound (FoCUS) views, including the anatomical structures one should expect to see and, importantly, how to obtain and optimize these images to extract the best diagnostic information. It will discuss the cardiac axis, probe handling, and pitfalls in image acquisition. The advanced section will introduce additional views, which are used in comprehensive echocardiography, because some are obtained inadvertently during FoCUS scanning and can be used to guide the operator back to standard views.

Artefacts

This chapter will describe the technical assumptions that produce artefacts and explain acoustic shadowing, enhancement, and reverberation, including the origin of A- and B-lines. It will also describe near-field, side lobe, and mirror image artefacts and how to avoid them. Finally, it will introduce the concept of foreshortening and how off-axis imaging can produce false images.

Lumbar puncture

Undertaking lumbar puncture in the intensive care patient can be technically challenging due to patient positioning and body habitus. Ultrasound guidance can improve the success rate and is relatively easy to learn. This chapter describes the normal sonoanatomy of the lumbar spine and how to use ultrasound to guide lumbar puncture.

Pericardial drainage

This chapter will explain how this potentially lifesaving procedure can be done using echocardiographic guidance, discussing indications, contraindications, monitoring and equipment, positioning and approach, technical aspects of the procedure using ultrasound, and post-procedure care.

Acute kidney injury

Ultrasound assessment of the urinary tract is frequently undertaken to identify post-renal or obstructive causes of renal failure. This chapter describes the normal renal sonoanatomy and the technique for scanning the renal tract, including the bladder. The sonographic features of the common pathology that may be identified are described, including the classification of hydronephrosis. The advanced section introduces the role of ultrasound in assessing renal perfusion.