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202 PART 2: General Management of the Patient

• O’Quinn R, Marini JJ. Pulmonary artery occlusion pressure: clini- GENERAL PRINCIPLES
cal physiology, measurement and interpretation. Am Rev Respir The intensivist uses observation, palpation, percussion, and auscultation
Dis. 1983;128:319. as key tools in their assessment of the critically ill patient. Conceptually,
• Qureshi AS, Shapiro RS, Leatherman JW. Use of bladder pressure ultrasonography is an extension of the standard physical examination,
to correct for the effect of expiratory muscle activity on central as it allows the clinician to directly assess the anatomy and function of
venous pressure. Intensive Care Med. 2007;33:1907. the body in a manner that complements the traditional bedside physi-
• Sharkey SW. A Guide to the Interpretation of Hemodynamic Data in cal examination. In accepting this simple principle, the intensivist uses
the Coronary Care Unit. Philadelphia, PA: Lippincott-Raven; 1997. ultrasonography at point of care whenever it is indicated, just as they
• Sharkey SW. Beyond the wedge: clinical physiology and the Swan- would evaluate the patient with standard physical examination methods.
Critical care ultrasonography is performed at the bedside. The front-
Ganz catheter. Am J Med. 1987;83:111.
line intensivist who is in charge of the management of the patient in
the intensive care unit (ICU) personally performs and interprets the
scan. The results are then promptly integrated into the management
REFERENCES plan. This is very different from the standard radiology or cardiology-
guided approach to ultrasonography in the ICU. In this latter circum-
Complete references available online at www.mhprofessional.com/hall
stance, the intensivist orders the test. Following some period of time,
often many hours, the test is performed. Sometime later, a radiologist
or cardiologist interprets the scan in a reading room without a clear
understanding of the clinical situation. The combination of time delay
ICU Ultrasonography
CHAPTER and clinical disassociation degrades the utility of the results compared
to the scan performed by the intensivist at the bedside. To compound
29 Paul Mayo the problem, resource allocation and economic pressures combine
Seth Koenig
to limit the ability of radiologists and cardiologists to perform serial
examinations. Critical illness implies instability and evolution of illness,
such that serial examinations are an implicit requirement for effective
management in the ICU. The concept of a limited or goal-directed
KEY POINTS ultrasonographic examination is different than the standard radiology
and cardiology approach.
• Ultrasonography has multiple applications in critical care medi- Intensivists use ultrasonography within a different paradigm. They
cine. The development of high-quality portable bedside machines do not order the test and wait for a delayed result. They do not rely on
now allows the frontline intensivist to perform the ultrasono- a technician or specialist to perform the examination. They do not try
graphic examination at the bedside of the critically ill patient. The to integrate a delayed reading into the immediate clinical management
results are applied for diagnostic purposes, to aid in the ongoing of the critically ill patient. Instead, they do everything personally: image
management of the patient, and for procedural guidance. acquisition, image interpretation, and the application of the results to
• The frontline intensivist who is in charge of the management of the clinical situation of the moment.
the patient in the intensive care unit (ICU) personally performs The radiology and cardiology community have been responsible for
and interprets the ultrasound scan at the patient bedside. This the development of the field of diagnostic ultrasonography. Through their
requires mastery of image acquisition and interpretation as well as work, the technology and validation of the field is fully established. The
the cognitive elements of the field. responsibility of the intensivist is to adapt a fully developed tool to
• Conceptually, ultrasonography is an extension of the standard the peculiar demands of the ICU. The issue for the intensivist does not
physical examination, as it allows the clinician to directly assess the so much relate to the utility of ultrasonography, but rather to the ques-
anatomy and function of the body in a manner that complements tion of how to achieve competence in its use. The intensivist must have
the traditional bedside physical examination. The examination definitive skill in all components of bedside ultrasonography: image
may be limited or goal-directed in scope and repeated whenever acquisition, image interpretation, and the cognitive elements required
there is clinical indication. The information derived from the scan for effective clinical applications. There is no expert radiologist or car-
is then integrated into the overall management plan. diologist involved; the intensivist is solely responsible for all aspects of
• Ultrasonographic examination of the heart (goal-directed echo- the examination.
cardiography), thorax (lung and pleura), abdomen (limited scope),
and venous anatomy (deep vein thrombosis) are key elements of SCOPE OF PRACTICE AND TRAINING
critical care ultrasonography. In addition, ultrasonography has
major utility for guidance of vascular access, thoracentesis, para- IN CRITICAL CARE ULTRASONOGRAPHY
centesis, and pericardiocentesis. The scope of practice of critical care ultrasonography includes all
aspects of modalities that have utility for diagnosis and management
of the critically ill patient. A recent Consensus Statement summarizes
the important elements that are required for competence in the field
1
INTRODUCTION and describes a reasonable scope of practice for the field. These include
thoracic, abdominal, vascular, and cardiac ultrasonography, with the
Ultrasonography has multiple applications in critical care medicine. The latter being subcategorized into basic and advanced echocardiography.
development of high-quality portable bedside machines now allows Advanced echocardiography is not a necessary part of competence in
the frontline intensivist to perform the ultrasonographic examination critical care ultrasonography for the intensivist, whereas mastery of
at the bedside of the critically ill patient. The results are applied for diag- basic echocardiography is a key component of competence.
nostic purposes, to aid in the ongoing management of the patient, and A recent Consensus Statement summarizes the important elements
for procedural guidance. The emphasis is on limited or goal-directed of training that are required to achieve competence. This document
2
examination, with serial examinations performed as indicated. This represents the opinion of a working group comprised of 17 national crit-
chapter will review some important aspects critical care ultrasonography. ical care societies including the three societies from the United States.

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