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2009 critical care ultrasonography


CRITICAL CARE

ULTRASONOGRAPHY


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CRITICAL CARE

ULTRASONOGRAPHY
Alexander Levitov, MD, FCCM
Senior Staff, Department of Medicine
Carilion Clinic
Professor, Medicine
Virginia Tech-Carilion School of Medicine
Roanoke, Virginia
Paul H. Mayo, MD, FCCP
Director MICU
Long Island Jewish Medical Center
New Hyde Park, New York
Professor of Clinical Medicine
Albert Einstein College of Medicine
Bronx, New York
Anthony D. Slonim, MD, DrPH, FCCM
Vice President, Medical Affairs
Carilion Roanoke Memorial Hospital
Senior Staff, Departments of Internal Medicine and Pediatrics
Carilion Clinic
Roanoke, Virginia
Professor, Medicine and Pediatrics
Virginia Tech-Carilion School of Medicine
Roanoke, Virginia

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To Dr. Alexandra Arcus (1896–1981), Veda, Marguerite who made this book possible,
and Irina, who makes everything possible.
A.L.
To my wife Charlotte Malasky, MD for all of her patience and support.
P.H.M.
To Terry, Michael, and Samantha . . . thanks for your love, support, and devotion.
A.D.S.


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Contents
Contributors............................................................................................................................................ix
Foreword..............................................................................................................................................xiii
SECTION I: General Principles and Impact of Ultrasound Use in the ICU
1. The Use of Ultrasound in the ICU: Potential Impact on Care........................................................ 3
Anthony D. Slonim
2. Physics of Sound, Ultrasound, and Doppler Effect and its Diagnostic Utility ............................. 11
Alexander Levitov
3. Transducers, Image Formation, and Artifacts ............................................................................ 27
Alexander Levitov
4. Training of the Critical Care Physician as Sonographer ............................................................. 45
Alexander Levitov, Paul H. Mayo, and Anthony D. Slonim
5. Pediatric Critical Care: Use of Bedside Ultrasonography ........................................................... 59
William Tsai and Anthony D. Slonim
SECTION II: Cardiac Sonography in the ICU
6. Goal-Directed Echocardiography in the ICU .............................................................................. 67
John M. Oropello, Anthony R. Manasia, and Martin Goldman
7. Transthoracic Echocardiography: Image Acquisition and Transducer Manipulation ................ 79
Seth Koenig and Paul H. Mayo
8. Transesophageal Echocardiography: Image Acquisition and Transducer Manipulation ............ 89
Pierre Kory and Paul H. Mayo
9. Echocardiographic Assessment of Left Ventricular Function and Hydration Status ................. 101
Balachundhar Subramaniam and Daniel Talmor
10. Echocardiographic Evaluation of Preload Responsiveness ...................................................... 115
Michel Slama, Julien Maizel, and Paul H. Mayo
11. Echocardiographic Diagnosis and Monitoring of Right Ventricular Function ........................... 125
Adolfo Kaplan
12. Echocardiographic Diagnosis of Cardiac Tamponade .............................................................. 135
Daniel A. Sweeney and Dorothea McAreavey
13. Echocardiographic Diagnosis and Monitoring of Acute Myocardial Infarction and
Associated Complications ....................................................................................................... 143
Rodney W. Savage
14. Echocardiographic Diagnosis of Cardiomyopathies ................................................................ 153
Narinder P. Bhalla, Amitabh Parashar, and Marguerite Underwood


viii

Contents

15. Echocardiographic Evaluation of Septic Shock ........................................................................ 173
Marc Mikulski, Olivier Axler, and Paul H. Mayo
16. Echocardiographic Evaluation of Valve Function and Endocarditis ......................................... 181
Paul H. Mayo
17. Echocardiographic Features of Adult Congenital Heart Disease .............................................. 191
Ren´ee J. Roberts and Anthony D. Slonim
18. Echocardiographic Evaluation of Cardiac Trauma ................................................................... 213
David A. Vitberg and Dorothea McAreavey
19. Echocardiographic Evaluation of Cardiopulmonary Interactions ............................................ 225
Antoine Vieillard-Baron
SECTION III: Ultrasound Evaluation of the Neck, Trunk and Extremities
20. Ultrasound Evaluation of the Neck and Upper Respiratory System ........................................ 235
Christian Butcher
21. Ultrasound Evaluation of the Pleura ........................................................................................ 245
Lewis Eisen and Peter Doelken
22. Ultrasound Evaluation of the Lung ......................................................................................... 251
Paul H. Mayo
23. Ultrasound Evaluation of the Abdomen ................................................................................... 259
Alan Cook and Heidi L. Frankel
24. Ultrasound Evaluation of the Renal System and the Bladder ................................................... 273
Yefim R. Sheynkin
25. Ultrasound Evaluation of the Pelvis ......................................................................................... 287
Michael Blaivas
26. Ultrasound Evaluation of the Peripheral Vascular System ....................................................... 295
James E. Foster, II and Kevin Wiseman
SECTION IV: Ultrasound Guidance for Procedures
27. Ultrasound-Guided Transthoracic Procedures ........................................................................ 311
Peter Doelken and Paul H. Mayo
28. Ultrasound Guidance for Abdominal and Soft Tissue Procedures ........................................... 323
Sameh Aziz, William J. Brunelli, Jr., and James S. Cain
29. Peripheral and Central Neuraxial Blocks in Critical Care Medicine .......................................... 337
Santhanam Suresh
30. Ultrasound Guidance for Vascular Access ............................................................................... 345
Christian Butcher
Appendix A: Glossary...........................................................................................................................361
Appendix B: Draft Ultrasound Reports by Body Region..........................................................................367

Index...................................................................................................................................................375


Contributors
Olivier Axler, MD, PhD, FCCP
Cardiovascular Department
Centre Hospitalier Territorial Gaston Bourret
Noumea, New Caledonia, France
Sameh Aziz, MD, FCCP
Senior Staff, Department of Medicine
Carilion Clinic, Roanoke, Virginia
Narinder P. Bhalla, MD
River Region Cardiology, Montgomery, Alabama
Michael Blaivas, MD
Professor of Emergency Medicine
Associate Professor of Internal Medicine
University of South Carolina, Columbia, South Carolina
Northside Hospital Forsyth
Department of Emergency Medicine, Atlanta, Georgia
William J. Brunelli, Jr., MPAS, RDMS, RDCS, PA-C
Radiology Associates of Roanoke, P.C.
Interventional Radiology
Lewis Gale Medical Center, Salem, Virginia
Christian Butcher, MD, FCCP
Assistant Clinical Professor of Medicine
Department of Medicine, University of Virginia
Charlottesville, Virginia
Assistant Professor of Clinical Medicine
Department of Medicine
Virginia College of Osteopathic Medicine
Blacksburg, Virginia
Pulmonary and Critical Care Faculty
Department of Medicine, Carilion Clinic
Roanoke, Virginia
James S. Cain, MD, FACP
Clinical Assistant Professor of Medicine
University of Virginia; Clinical
Assistant Professor of Medicine
Edward Via School of Medicine, Virginia Tech
Chief of Medicine Department
Medical Director for Dialysis Services
Carilion Roanoke Memorial Hospital, Roanoke, Virginia

Alan Cook, MD
Trauma Surgeon, East Texas Medical Center
Tyler, Texas
Peter Doelken, MD
Associate Professor, Division of Pulmonary
Critical Care, Allergy, and Sleep Medicine
Medical University of South Carolina
Medical University Hospital
Division of Pulmonary
Critical Care, Allergy, and Sleep Medicine
Charleston, South Carolina
Lewis Eisen, MD
Assistant Professor of Medicine
Division of Critical Care Medicine
Albert Einstein College of Medicine
Attending Physician, Division of Critical Care Medicine
Montefiore Medical Center, Bronx, New York
James E. Foster, II, MD, FACS, RVT
Asst. Professor of Clinical Surgery
University of Virginia
Medical Director, Noninvasive Vascular Laboratory
Carilion Clinic, Roanoke, Virginia
Heidi L. Frankel, MD
Professor of Surgery
University of Texas Southwestern, Dallas, Texas
Martin Goldman, MD
Professor, Medicine, Department of Cardiology
Mount Sinai School of Medicine
New York, New York
Adolfo Kaplan, MD
Pulmonary and Sleep Center of the Valley
Weslaco, Texas
Seth Koenig, MD
Attending Physician, Division of Pulmonary
Critical Care, and Sleep Medicine
Long Island Jewish Medical Center
New Hyde Park, New York


x

Contributors

Pierre Kory, MD, MPA
Attending Physician
Division of Pulmonary and Critical Care Medicine
Beth Israel Medical Center, New York, New York

Rodney W. Savage, MD
Consultants in Cardiology, Roanoke, Virginia

Alexander Levitov, MD, FCCM
Senior Staff, Department of Medicine, Carilion Clinic
Professor, Medicine
Virginia Tech-Carilion School of Medicine
Roanoke, Virginia

Yefim R. Sheynkin, MD, FACS
Associate Professor of Clinical Urology
Department of Urology
State University of New York at Stony Brook
Department of Urology
Stony Brook University Medical Center
Stony Brook, New York

Julien Maizel, MD
Unite de Reanimation Medicale
Service de Nephrologie, CHU Sud, Amiens, France

Michel Slama, MD
CHU Sud, Unit´e de R´eanimation M´edicale
Service de N´ephrologie, Amiens, France

Anthony R. Manasia, MD
Associate Professor of Surgery and Medicine
Department of Surgery, Mount Sinai School of Medicine
New York, New York

Anthony D. Slonim, MD, DrPH, FCCM
Vice President Medical Affairs
Carilion Roanoke Memorial Hospital
Senior Staff
Departments of Internal Medicine and Pediatrics
Carilion Clinic, Roanoke, Virginia
Professor, Medicine and Pediatrics
Virginia Tech-Carilion School of Medicine
Roanoke, Virginia

Paul H. Mayo, MD, FCCP
Division of Pulmonary, Critical Care, and
Sleep Medicine, Long Island Jewish Medical Center
New Hyde Park, New York
Dorothea McAreavey, MD, FACC
Critical Care Medicine Department
National Institutes of Health
Bethesda, Maryland
Marc Mikulski, MD
Anesthesiology and Critical Care Department
Centre Hospitalier Territorial Gaston Bourret
Noumea, New Caledonia, France
John M. Oropello, MD
Professor of Surgery and Medicine
Department of Surgery
Mount Sinai School of Medicine
New York, New York

Balachundhar Subramaniam, MD
Assistant Professor, Department of Anesthesiology
Harvard Medical School
Director of Cardiac Anesthesia Research
Beth Israel Deaconess Medical Center
Boston, Massachusetts
Santhanam Suresh, MD, FAAP
Director of Research, Children’s Memorial Hospital
Associate Professor of Anesthesiology and Pediatrics
Northwestern University
Feinberg School of Medicine, Chicago, Illinois
Daniel A. Sweeney, MD
Critical Care Department
National Institutes of Health, Bethesda, Maryland

Amitabh Parashar, MD
Assistant Professor
University of Virginia School of Medicine
Department of Internal Medicine
Charlottesville, Virginia
Assistnat Professor, Department of Internal Medicine
Virginia Tech Carilion School of Medicine
Carilion Roanoke Memorial Hospital, Roanoke, Virginia

Daniel Talmor, MD, MPH
Associate Professor of Anesthesia
Harvard Medical School
Director of Trauma Anesthesia and Critical Care
Department of Anesthesia and Critical Care
Beth Israel Deaconess Medical Center
Boston, Massachusetts

Ren´ee J. Roberts, MD
Assistant Professor of Anesthesiology and Pediatrics
Director of Anesthesia Support Services
Children’s National Medical Center
The George Washington University Medical Center
Washington, DC

William Tsai, MD
Attending Physician
Critical Care Medicine and Emergency Medicine
Department of Pediatrics
Levine Children’s Hospital at Carolinas Medical Center
Charlotte, North Carolina


Contributors
Marguerite Underwood, RN, RDCS
Echocardiography Department
Carilion Clinic, Roanoke, Virginia
Antoine Vieillard-Baron, MD
Professor of Medicine
Universit´e de Versailles Saint
Quentin en Yvelines, France

opital Ambroise Par´e
Intensive Care Unit, Boulogne, France

David A. Vitberg, MD
Emergency Department
Baltimore Washington Medical Center
Glen Burnie, Maryland
Kevin Wiseman, BS, RVT, RDMS
Non-invasive Vascular Laboratory
Carilion Clinic, Roanoke, Virginia

xi


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Foreword
As technology improves diagnosis and treatment,
physicians are either “early adopters” or those who
wait to see if a new approach is really better than the
current standard. The “adopters” are challenged with
becoming proficient in new skills, while those who resist need to be convinced that change is called for,
and that it justifies the costs of time and money. Buying new equipment always provokes discussion of who
pays for it, and what must be sacrificed. Finally, a new
program may step on someone else’s turf. There are
disputes about who is best qualified to use the technology, along with calculations of the financial impact
on existing programs and the potential legal liability of
using new methods.
The introduction of ultrasonography into frontline
critical care medicine is a case in point, and obstacles to its current wide use are similar to those that
appeared with the introduction of other new technology that ultimately revolutionized the practice of
pulmonary and critical care medicine. In the 1970s, flexible bronchoscopy gave pulmonary and critical care
physicians a tool to expand their diagnostic abilities beyond the history, physical examination, and the chest
radiograph. They had to learn how to use the bronchoscope, find the money to buy the equipment, and overcome the objections of many otolaryngologists and
thoracic surgeons who strongly believed that people
from internal medicine backgrounds had no business
endoscoping the airways, no less performing biopsies
of the airway and lung parenchyma. Of course, this resolved over several years, and flexible bronchoscopy
is now a core procedure of pulmonary and critical care
medicine physicians.
With ultrasonography, a similar conflict is now being
played out between new practitioners, in this case critical care clinicians, and an “old guard” of radiologists
and cardiologists. Ultrasonography has such strong

utility in critical care medicine that all intensivists are
strongly encouraged to become proficient in its bedside applications. Intensivists are capable of learning
a variety ultrasound skills that greatly improve their
effectiveness in bedside diagnosis and management,
make their procedures safer, and liberate them from a
dependence on other specialists who are not always
immediately available to care for the critically ill patient. An intensivist is responsible for the whole patient; and now, armed with a good ultrasound machine
and the right skills, is capable of acquiring images that
answer urgent clinical questions, interpreting and acting on these images in the context of an overall management strategy.
The technology has existed for decades, and has
been used daily by internists and intensivists in Europe and in parts of Asia. North American intensivists
developed proficiency in ultrasonography only several years ago. Radiologists and cardiologists may fret
about whether intensivists can acquire the competencies to use this technology properly, but with proper
training and experience, ultrasound is now in the hands
of ICU physicians who use it with excellent results for
their patients.
A key element to training in critical ultrasonography
is mastery of the knowledge base of the field. This textbook is designed to meet the needs of the critical care
ultrasonographer who requires a comprehensive and
coherent presentation of the core knowledge of this
discipline; it achieves that goal admirably. This book
is intended to be used by intensivists; its authors are
expert practicing intensivists and ultrasonographers.
Through years of dedicated study and direct experience, they use ultrasound every day in the diagnosis
and management of patients with complex cardiac, pulmonary, renal, and digestive diseases. The chapters of
this text review the basic technology and physics of


xiv

Foreword

ultrasonography, and give detailed descriptions of its
applications in diagnosis in each organ system, as well
as its role in the performance of common ICU procedures.
This book defines the cognitive basis of the field;
the intensivist who seeks to develop competence must
combine this knowledge with hands-on bedside training in image acquisition and interpretation. For the experienced critical care ultrasonographer, the book provides a comprehensive reference for answering complex questions. Regardless of each clinician’s current
level of knowledge and skill, this text is an important
resource for all practicing intenstivists, because like

bronchoscopy in the 1970s, proficiency in ultrasonography will eventually be adopted by all intensivists, as
the use of this technology will certainly serve our patients well.
Mark J. Rosen, MD, FCCP, FCCM, FACP
Chief
Division of Pulmonary, Critical Care and Sleep Medicine
North Shore University Hospital and
Long Island Jewish Medical Center
Professor of Medicine
Albert Einstein College of Medicine
Past President, American College of Chest Physicians


SECTION I

GENERAL
PRINCIPLES AND
IMPACT OF
ULTRASOUND
USE IN THE ICU


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CHAPTER 1

The Use of Ultrasound in the ICU:
Potential Impact on Care
Anthony D. Slonim

INTRODUCTION
Medical care for the critically ill usually advances in an
incremental fashion. Physicians, for the most part, are
a conservative group and critical care physicians are
an important subgroup that tends to value a scientific
approach and evidence-based decision-making. Experimental evidence requires time to generate, appropriate
vetting through the peer review process, and then additional time prior to becoming engrained in clinical
practice at the bedside for the benefit of patients. As a
result, it is only through retrospective evaluation that
the improvements in intensive care unit (ICU) care can
be seen.
There are several important and relatively recent examples of this incremental approach in critical care, including low-tidal-volume ventilation, the management
of hyperglycemia, and the use of hypertonic saline
for acute elevations in intracranial pressure. Despite
these well-defined examples, critically ill patients benefit from these approaches to a lesser degree than expected because their physicians fail to prescribe them
in a large proportion of cases, thus compromising the
quality of care for these critically ill patients. This is
one example of how physicians can improve their own
work by focusing on the elements of physician decisionmaking, particularly the process steps, and aligning
them with the patients’ needs.
Rarely, the quality of care for patient populations
undergoes a major shift that can be thought of as
revolutionary rather than evolutionary. These shifts,
when viewed retrospectively, have usually involved
major technological advances. For example, the use
of fiberoptics in medicine has revolutionized the care
of patients requiring diagnostic and therapeutic procedures. These patients now undergo relatively minor
interventions as compared to what would have been experienced just a few decades ago. These shifts also involve practice settings. Surgeries formerly performed
on inpatients are now performed on an ambulatory

basis. Finally, these shifts involve physicians from
different disciplines. Interventional radiologists are
now performing procedures that previously required
a surgeon. Cardiologists are now treating coronary
syndromes in ways that previously required cardiac
surgery.
Ultrasound use in the ICU is one such shift that
decades from now will be viewed retrospectively as
a revolutionary phenomenon that advanced the care
of critically ill patients. However, the current challenge
is to think prospectively, not retrospectively, about implementing this proven technology for diagnostic and
therapeutic decision-making in a practice setting that
is outside of the radiology suite and by providers who
are neither radiologists nor cardiologists while the evidence base and applications are being further established. This book provides an opportunity to consider
methods of applying this tool, in a thoughtful manner, at the bedside to advance the quality of care for
this vulnerable subgroup of patients. Through an approach that evaluates the risks and benefits of using
ultrasound in the ICU, physicians will be better able to
understand how this technology can influence the care
of their ICU patients.

HEALTH CARE QUALITY
Over the last 30 years, increased attention has been
paid to the issues of quality health care. Donabedian
provided a useful paradigm to consider the issue of
quality by using structure, process, and outcome as
three major components of the quality definition and
applying it to health care. Since then, considerable effort has been put into further defining performance
measures related to health care quality around six
fundamental domains promulgated by the Institute of
Medicine (IOM) in their seminal work titled Crossing the
Quality Chasm and applied to a number of medical disciplines. These six domains include safety, effectiveness,


4

General Principles and Impact of Ultrasound Use in the ICU

TABLE 1.1. The definitions of the IOM domains
IOM domain
Safety

Effectiveness

Efficiency
Equity

Timeliness

Patient-Centeredness

Definition
To limit the unintentional harm
associated with the delivery of
health care
To use evidence-based
practices, the best scientific
evidence, clinical expertise,
and patient values to achieve
the best outcomes for patients
To provide care that is done
well and with limited waste
To provide care that is free
from bias related to personal
demographics like gender,
race, ethnicity, insurance
status, or income
To provide care without
unnecessary wait and to
assure that patients have
access to the care they need
To provide care that reflects a
focus on the patient’s needs,
including empathy,
compassion, and respect

IOM indicates Institute of Medicine.

efficiency, equity, timeliness, and patient-centeredness
(Table 1.1).

Safety
Safety is the domain concerned with medical errors that occur during the health care experience.
These errors are classified as diagnostic errors, treatment errors, preventive errors, and “other” or unclassified errors. Diagnostic errors include delays or errors in
diagnosis, the failure in applying appropriate diagnostic testing, and the failure to respond to the results of
testing. Treatment errors result from errors in the performance of a procedure or test, delays in treatment, or
providing care that is simply not indicated. Preventive
errors occur from failing to provide prophylactic care
or inadequately monitoring the patient. “Other” errors
result from failures of the equipment or team, such as
communication errors or performance issues.
Using this classification scheme, one can see how
ultrasound use in the ICU may impact the safety of patients. Diagnostic errors may arise from operator inexperience in either acquiring or reading ultrasound

images, leading to inaccurate or erroneous diagnoses.
Artifacts that are misinterpreted represent another potential safety problem for patients. While ultrasound
use in the ICU may compromise safety in important
ways, there are also ways in which it improves care. Ultrasound as a diagnostic test can be applied when and
where it is needed for the patients most likely to benefit. In addition, since the operator and interpreter are
the same physician, the intensivist, the vulnerability of
not having test results responded to is reduced.
Treatment errors are another category of safety errors. In this category, both test performance issues
and using a test that is not indicated are important.
If ultrasound is performed incorrectly, the results may
be incorrect and be acted upon more quickly. Hence,
ultrasound use in the ICU may compromise safety by
its ready availability. The lead time from the performance of the procedure to a resulted report that can
be acted upon in traditional diagnostic testing may be
providing a safety net that disappears when the tool
and operators are readily available. With ultrasound
use in the ICU, a finding can be immediately acted upon
for the benefit of the patient. The problem arises when
the finding is a misinterpretation.
Ready availability of a test may also lead to excesses
in use and treatment errors manifested in two specific ways. First, ICU physicians may use ultrasound
because it is available and not because it is the best
test to answer a particular clinical question. Second,
the fact that a technology exists does not mean that it
needs to be used on all patients. Care must be taken
to assure that as a discipline, clinical questions are answered with the right tool and not the most technologically advanced or newest tool that happens to be
available in the ICU. There is no need for ultrasound use
when the physical examination will do just fine. However, there are opportunities to enhance the physical
examination with a thoughtful and more in-depth assessment using ultrasound as an additional technique
if one has been properly trained. If the test is not indicated, it is simply not indicated and its availability
should not change the clinical indications. Ultrasound
use can also improve safety with treatment errors because the findings are immediately available, communicated, documented in the record, and acted upon,
all within a relatively short time span. In addition, by
providing real-time guidance for invasive procedures,
ultrasound allows direct visualization to assure accuracy of placement and avoidance of complications.
Preventive and unclassified errors can also compromise the safety of the ICU patient. Any time the intensivist is diverted from caring for the patient while


The Use of Ultrasound in the ICU: Potential Impact on Care
focusing on a procedure, safety events can occur from
inadequate monitoring. Assuring that ultrasound is
used in a broader context and that the “whole” patient remains under the watchful eye of the intensivist
is important during the procedure. Safety is likewise
improved by bedside ultrasound in this dimension because patients do not need to move from the ICU to
receive their testing. Finally, the bedside ultrasound
evaluation is only as good as the documentation and
communication of the results. Failure to document in
the medical record and report the care to colleagues
creates risk to the patient that can be overcome by
inserting a copy of the study and a report in the record and effectively communicating to staff and other
physicians.

Effectiveness
Effectiveness is the domain concerned with using
evidence-based principles, provider experience, and
patient values in achieving the desired care. This includes the use of clinical guidelines that are evidence
based, contemporary, and updated to keep pace with
the evolving research. When evidence from randomized trials does not exist, other evidentiary methods
can be used to help inform the care of patients.
When considering effectiveness, one needs to be
careful not to fall into the trap of waiting for the literature to document all of the evidence with an available
technology before it is used. That approach will take
years and inadvertently prevent patients from benefiting from a useful bedside technology. Despite the
fact that empiric evidence documenting the use of bedside ultrasound in the ICU is limited, there is face validity to recognizing that ultrasound is a simple diagnostic test that adds benefits to patients and has been
performed in the disciplines of radiology, obstetrics,
emergency medicine, and cardiology for a number of
years. Further, the American Institute of Ultrasound
in Medicine (AIUM), an organization that has existed
since the 1950s, has a number of official statements,
practice guidelines, and technical standards that can
help to inform on the use of ultrasound more broadly,
including in the ICU. In addition, the inexperienced operator and interpreter can also impair the effectiveness
of the study.

Efficiency
Efficiency helps shape the use of health care resources
by recognizing that there are limitations to the supply
of resources that can be provided and by optimizing

5

the value of the resources, by enhancing quality and
limiting waste. The real opportunity for improving efficiency with ultrasound in the ICU is that it provides
important answers to questions without the risk and
danger of transporting a critically ill patient to another
location. Further, having a test immediately available
that can be performed by the providers caring for the
patient helps to alleviate unnecessary steps in the process of obtaining and interpreting the test.

Equity
Equity is the domain responsible for assuring that
health care is provided to patients without bias or discrimination based on personal demographics and for
assuring equal access to health care services for patient populations. Ultrasound, when available as a tool
in the ICU, provides ready and immediate availability
on a 24/7 basis to patients regardless of their personal
demographics. One potential problem is that currently
the technology and expertise are not universally available. Hence, from an access perspective, the ICU to
which a patient gets admitted may be unable to provide the service for the patients it serves. As a result,
patients experience inequities in access to available
technologies for diagnosis or treatment, particularly
when ultrasound is unavailable 24/7 from the radiology department.

Timeliness
Timeliness is the domain responsible for assuring that
patients receive the diagnostic and therapeutic services without delay when they need them. This improved access allows patients to receive the care
they need when they need it. Similar challenges exist with timeliness as with equity. Namely, the ultrasound equipment and expertise may not be available
24/7 when the patient needs it, and the radiology department may also not have the service available.

Patient-Centeredness
Patient-centeredness is the domain where the patient
and family are placed as the focal point of the health
care experience. It also provides for the inclusion of
patient wishes in the determination of what services
are provided. Services that are patient-centered are
those that provide care when and where it is needed by
those who are most likely to benefit the patient. In addition, patient-centeredness ensures “service” aspects
of health care quality including satisfaction with the


6

General Principles and Impact of Ultrasound Use in the ICU

TABLE 1.2. Classification of ICU physician-specific quality components based upon Donabedian’s structure,
process, and outcome framework
Structure
“Bricks and mortar”

Personnel

Process∗

Data gathering

Interpretation

Decision-making

Action

ICU itself
Monitoring equipment
Patient care equipment
E.g.: Ventilators
Ultrasound machines
Medication pumps
Physicians
ICU physicians
Primary care physicians
Consulting physicians
Residents and fellows
Other personnel
ICU nurses
Respiratory therapists
Pharmacists
Social workers
ICU management
Nursing director
ICU medical director
Hospital management
Admission
History
Thorough, timely, and accurate
Physical examination
Thorough, timely, and accurate
Consultant input
Thorough, timely, and accurate
Diagnostic testing
Appropriate test, performed
Pattern recognition from data
Clinical context from the patient
Clinical knowledge based on training and experience
Knowledge from EBM and current literature
Formulation of a plan consistent with patient choice
Medical treatment plan
Surgical treatment plan
Care management plan
Gather further data
Revisit history
Reexamine patient
Perform further diagnostics
Implement a care management plan
Assure appropriate anticipatory measures
E.g.: Gastrointestinal prophylaxis
Deep venous thrombosis prophylaxis
Assure appropriate therapeutic measures
E.g.: Manage hyperglycemia
Low tidal volume ventilation
Elevate head of bed
(continued )


The Use of Ultrasound in the ICU: Potential Impact on Care

7

TABLE 1.2. (Continued )
Implement the medical treatment plan
Appropriate medication use based on EBM
Appropriate diagnostic tests based on sensitivity and specificity
Appropriate therapeutic plan based on EBM
Implement the surgical treatment plan
Right procedure
Performed safely and correctly
Intended outcome without complications
Perform a procedure
Right procedure
Performed safely and correctly
Intended outcome without complications
ICU mortality
ICU morbidity
Physical disabilities
Cognitive disabilities
ICU length of stay
Costs
Duration of ICU therapies
Nosocomial infections
Procedure complications

Outcome

∗Physician-specific

processes. ICU indicates Intensive care unit; EBM, Evidence-based medicine.

technical aspects of the procedure. For ultrasound use
in the ICU, the provision of the service at the bedside
without unnecessary transportation, pain, and burden
on the patient is representative of how ultrasound use
can have a positive influence in this domain.

“DOCTOR QUALITY”
While the IOM report provides a useful framework for
health care quality, physicians tend to think differently
about health care quality. Specifically, when physicians
consider quality they are often thinking about the care
that they, rather than the health care team provides.
Donabedian’s constructs of structure, process, and
outcome are particularly helpful here in assisting the
physician in identifying his or her role in the provision
of quality care to patients (Table 1.2).

Structure
From a structural perspective, the bricks and mortar of the ICU, including its walls, the monitors, the
equipment, and maybe even the ultrasound machine
are, by implication, what constitutes an ICU. However,
the bricks and mortar alone do not make an ICU. It
is the people, both providers and patients, and their

expertise and interactions, that constitute the optimal
delivery of ICU care. Structurally, physicians need to
consider their role within the health care team. The organization of the ICU, how it is managed, and the management of other physicians, including primary care
physicians, other consultants, residents and fellows determines the care the patients receive. The physician
would be remiss not to consider the nurses, therapists,
and ancillary departments who assure the appropriate
delivery of care to the patients when the physician is
not in attendance. When taken together, these elements
are the structural components of ICU care to which
Donabedian might refer (Table 1.2).

Process
Clinical processes, or the interactions between providers and their patients and providers with one another, are also important for physicians to consider.
Nurses, in their discipline, can be very process focused,
but physicians often lack this component in their training. Therefore, when asked to address specific process
steps, like the implementation of the vascular access
bundle, physicians often fail to recognize how such detailed specification of process actually makes a difference in outcome. However, some would argue that the


8

General Principles and Impact of Ultrasound Use in the ICU

process steps are critical to patient care, particularly
key physician processes (Table 1.2).

Doctor Processes and Medical
Decision-Making
Taking a moment to consider doctor quality is helpful when considering how processes are operative in
improving health care quality. The term “doctor quality” is used to describe the elements of the medical
decision-making process that only physicians can influence. Doctor quality can be thought of through the
key core processes of the ICU physician as he or she
cares for the critically ill patient from ICU admission
through discharge (Figure 1.1, Table 1.2). Traditional
medical decision-making has four iterative steps that
assist physicians with making decisions for their patients (Figure 1.1). The first step is data gathering.
Physicians use their history, physical examination, diagnostic testing, consultants, and other members of
the health care team to assist them in assuring that
they have collected appropriate data upon which to
base their clinical decisions (Table 1.2). The next step is
for the physician to interpret the gathered data within
the clinical context of the patient. This step involves
assembling the collected data to see if it coalesces into
a particular pattern and seeing if that pattern is consistent with the patient’s presentation and findings. The
next step is decision-making. Here, the physician may
gather additional data by calling a consultant or ordering additional testing. If sufficient data has been
gathered, the physician may formulate a medical treatment plan and reevaluate the plan’s success as time
progresses (Table 1.2). The physician may recommend
or perform a procedure, the outcome of which may assist with diagnosis or treatment. Finally, as the last step
ICU
Admission

ICU
Discharge

ICU Patient Trajectory

Interpret
Data

Gather
Data

Providers

Make
Decisions

of medical decision-making, the physician must take action. A plan that is not acted upon or a procedure or
test that is thought about but not performed does not
help the patient. These four steps allow the physician
to think through and organize their work (Figure 1.1,
Table 1.2).

Outcomes
Finally, outcomes represent the culmination of the
health care experience. Physicians often focus on outcome measures as the result of their work. In the ICU environment, mortality is a traditional outcome measure
that is important, quantifiable, and often discussed
(Table 1.2). There are other outcome measures of relevance to ICU physicians, including the use of ICU specific therapies, length of stay, cognitive and physical
outcomes, and morbidities arising from the episode of
care (Table 1.2). However, since outcomes tend to be
the end result of a series of process steps that are temporally distinct, it is often important for the physician
to focus on both components of quality. Outcomes have
been held in high regard for considerable time, almost
to the exclusion of process measures. Physicians will
only be able to improve the quality of care for their
patients by focusing on both the process and outcome
components of health care quality.

THE USE OF ULTRASOUND IN THE
ICU: IMPACT ON CARE
The value of providing an overview to health care quality and the specific ways in which physicians are both
affected and can affect it is that it provides a useful
framework for further discussing the role of bedside
ultrasound in the ICU and the potential to impact care
for ICU patients. Table 1.3 uses the IOM domains and
the medical decision-making process to help identify
the opportunities to influence care in the ICU with the
use of this important technology. By understanding the
points in each of the IOM domains or the risk point
in the decision-making process, the physician can approach the use of ultrasound in the ICU with improved
recognition of the risks and benefits applied in this
setting.

CONCLUSION
Take
Action

Figure 1.1. A model for medical decision-making that
occurs throughout the ICU course.

Overall, the use of bedside ultrasound is an important
application of a well-described technology for diagnostic and therapeutic decision-making. Like most other
new applications, it has risks and benefits associated


The Use of Ultrasound in the ICU: Potential Impact on Care

9

TABLE 1.3. The characteristics associated with ultrasound use in the ICU and their ability to impact care
from the perspective of the IOM domains and physician-specific processes in medical decision-making
Safety

Effectiveness

Data gathering
Portable

Interpretation
Based on operator
training/experience

Available 24/7

Based on experience
acquiring images

Noninvasive
No radiation exposure

Based on experience
interpreting images
Easy to learn

Easy to learn

Expertise variable

Expertise variable
Potential for excess use
because of availability
May fail to use, more difficult
to obtain, but better
diagnostic tests
Availability causes overuse
when traditional methods of
physical examination would
be fine
Attention to monitoring
patient while performing
ultrasound needs to be
assured
Testing performed without
moving patients and while
maintaining ICU-level
monitoring and therapy
Clear indications

Limited EBM for ICU
Extensive EBM for
ultrasound use generally
Requires acoustic window

Decision making
Based on operator
training/experience
and confidence in
findings

Action
Improves procedure
performance

Avoids procedural
complications by using
direct visualization
Avoids delays in
interpretation
Misinterpretations may
lead to errors in action
Findings, interpretation,
and actions need to be
documented and
communicated
appropriately

Based on operator
training/experience

Based on operator
training/experience

Limited EBM for ICU
Extensive EBM for
ultrasound use
generally
Requires ability to
distinguish artifacts

Limited EBM for ICU
Extensive EBM for
ultrasound use
generally

Available EBM for
ultrasound use in
specific disciplines like
radiology, emergency
medicine, surgery,
trauma, obstetrics/
gynecology
Limited EBM for ICU
Extensive EBM for
ultrasound use generally

(continued )


10

General Principles and Impact of Ultrasound Use in the ICU

TABLE 1.3. (Continued )
Efficiency

Timeliness

Equity

Patientcenteredness

Data gathering
Operator/decision-maker
are the same providing
clinical context for
focused evaluation

Decision making
Lacks objectivity
between operator and
interpreter subjects
to confirmatory bias

Action
No lag time between
decision and action; risky
if decision is incorrect

No need for patient
transport
May not be available in all
ICUs 24/7
May not be available in all
ICUs 24/7

Interpretation
Operator/decisionmaker are the same
providing clinical
context for focused
evaluation
Immediate availability
of information
May not be available in
all ICUs 24/7
May not be available in
all ICUs 24/7

May not be available
in all ICUs 24/7

May not be available in
all ICUs 24/7

May not be available
in all ICUs 24/7

Not available in all ICUs

Not available in all ICUs

Not available by all ICU
providers
Improves access for all
ICU patients
Not available in all ICUs

Not available by all ICU
providers
Improves access for
all ICU patients
Not available in all
ICUs
Not available by all ICU
providers
Operator/decisionmaker are the
same
Lacks objectivity
between operator and
interpreter

Not available in all
ICUs
Not available by all
ICU providers
Improves access for
all ICU patients
Not available in all
ICUs
Not available by all
ICU providers
Immediate
information available
for patient and family

May not be available in
all ICUs 24/7
Operator/decision-maker
are the same
Not available in all ICUs

Not available by all ICU
providers
Alleviates the need for ICU
patient transportation and
its pain and risks
Expands the breadth of
diagnostic and procedural
capabilities

Not available by all ICU
providers
Improves access for all
ICU patients
Not available in all ICUs
Not available by all ICU
providers
Immediate access to
specific interventions
and next steps

IOM indicates Institute of Medicine; EBM, Evidence-based medicine; ICU, intensive care unit.

with its use. For intensivists to optimize this technology for their patients, an understanding of their
own decision-making process is important. I hope this

chapter has provided a context upon which further use
of this technology can be evaluated for the benefit of
the critically ill patient.

Suggested Reading
Available at: http://www.aium.org/publications/guidelines
StatementsX.aspx#statements. Accessed October 25,
2008.
Available at: http://www.aium.org/publications/technical/
techIntro.asp. Accessed October 25, 2008.
Morris AH. Developing and implementing computerized protocols for standardization of clinical decisions. Ann Intern
Med. 2000;132:373–383.

Institute of Medicine Committee on Quality of Health Care in
America. Crossing the Quality Chasm: A New Health System
for the 21st Century. Washington, DC: National Academies
Press; 2001.
Slonim AD, Pollack MM. Evaluating Pediatric Critical Care.
In: Fink MP, Abraham E, Vincent JL, Kochanek PM, eds.
Textbook of Critical Care. 5th ed. Philadelphia, Pa: Elsevier/
Saunders; 2005:2207–2215.


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