| The following two articles by Dr.
Cohen are meant to give the anesthesiology
community a glimpse at how the Committee
on Patient Safety and Risk Management
intends to help educate the public about
anesthesiology’s important role
in patient safety. This committee will
be working with ASA’s Committee
on Communications to develop such documents
and distribute them to appropriate target
audiences. |
|
What Does the Anesthesiologist Do During the Operation?
 he
role of the anesthesiologist is to provide comprehensive
medical care to the patient undergoing surgical
and diagnostic procedures. Anesthesiologists also
manage the patient’s medical care throughout
the period of their recovery from anesthesia, including
postoperative intensive care when needed. Sometimes
anesthesiologists manage anesthesia directly and
sometimes they medically direct anesthesiologist
assistants or nurse anesthetists. Regardless, the
anesthesiologist is responsible for the overall
care of the patient throughout the anesthetic.
Before the operation can begin, the anesthesiologist
evaluates the patient’s medical history and
performs a physical examination that focuses on
the medical needs of the patient. This examination
concentrates on the organ systems that are challenged
during operations. The aim of this preoperative
evaluation is to discover risk factors that must
be taken into account. These risk factors include
allergies, chronic lung disease, heart disease,
diabetes, thyroid disease, problems related to obesity,
difficult access to the circulation or airway, and
inherited traits that might cause problems such
as malignant hyperthermia or increased sensitivity
to muscle relaxants. Because of the variety of disorders
that can have an impact on the safety of anesthesia,
it is important for the patient to provide the anesthesiologist
with an accurate report of allergies, past hospitalizations,
surgical procedures, family-related problems with
anesthesia, diagnostic tests, medications being
taken and any concerns that may have been raised
regarding previous anesthetics.
The preoperative evaluation also provides the anesthesiologist
with the opportunity to let the patient know what
to expect and to review the risks and benefits of
available treatment options. This conversation is
known as “informed consent.” It is an
opportunity to discuss what the likely challenges
will be and how they will be addressed. Informed
consent for anesthesia can only be obtained by a
person who is trained to provide anesthesia. It
is not the form that is signed acknowledging that
consent has been given.
After the preoperative evaluation is complete, the
patient is taken to the operating room and placed
on the operating table. The anesthesiologist then
attaches several devices to monitor the patient’s
physical well-being, including electrocardiogram,
blood pressure cuff and blood oxygen saturation
probe. Occasionally, for some heart operations or
those where the regulation of blood pressure can
be a problem, the anesthesiologist will insert a
plastic vascular catheter into an artery in the
wrist. This will be used to monitor blood pressure
continuously and provide a source for obtaining
blood for laboratory tests. During or shortly after
placing the monitors, the patient will be asked
to breathe 100-percent oxygen for several minutes.
The exhaled gas will be analyzed to determine adequate
ventilation, as indicated by the exhaled carbon
dioxide level, and to carefully measure and control
the level of inhaled oxygen and anesthetics. The
exhaled gas will be measured throughout the operation.
A monitoring device is often placed on the forehead
to aid in evaluating the level of anesthesia during
the operation.
When all of the monitors are in place, the anesthesiologist
will check vital signs and then induce anesthesia,
usually by injecting sodium pentothal or propofol
intravenously. At this point, patients lose consciousness
and usually stop breathing on their own. The anesthesiologist
will then ventilate the patient using a facemask
attached to a ventilation bag on the anesthesia
machine. After giving a muscle relaxant to facilitate
the examination of the oral airway and larynx, the
anesthesiologist uses a laryngoscope to see the
larynx and place an endotracheal tube through which
the patient will be ventilated during the operation.
The end of this tube, about the diameter of the
pinky finger, sits in the upper trachea and has
a balloon cuff surrounding it. The cuff is inflated
to prevent anything that enters the mouth, such
as acid from the stomach, from entering the lungs.
If the anesthesiologist anticipates that placing
the endotracheal tube may be difficult or if it
proves unexpectedly difficult, this tube may be
placed under anesthesia or sedation using special
techniques. These techniques include bronchoscopy
and laryngoscopy with devices specially designed
to help facilitate intubation of the difficult airway.
Before surgery begins, other invasive monitors may
be inserted to continuously measure blood pressure
and cardiac performance during the operation. For
example, during liver and heart surgery as well
as other major operations, the anesthesiologist
may place a large catheter into the internal jugular
or subclavian vein. Another catheter can be placed
through this large-bore catheter and passed through
the chambers of the right heart into the pulmonary
artery to measure its pressure as well as cardiac
output. These measurements are useful in optimizing
cardiac performance and intravenous fluid management.
Occasionally the anesthesiologist may need to evaluate
cardiac function by examining the heart using a
cardiac ultrasound probe. This probe is inserted
into the esophagus and produces a picture of the
beating heart and its valves.
During the operation, the anesthesiologist gives
a variety of drugs to maintain anesthesia and preserve
stable cardiac and lung function. Sometimes this
involves the use of a variety of drugs and fluids,
especially when the operation is associated with
major interruption of blood flow or with blood loss.
If blood loss is substantial, the anesthesiologist
will replace the lost blood and other blood components
in order to normalize the ability of the blood to
coagulate. These components may include fresh, frozen
plasma, platelets and other clotting factors. During
some procedures, such as vascular or open-heart
operations, anticoagulants may be needed to suspend
coagulation. In this case, the anesthesiologist
will administer and control the level of anticoagulants
and later neutralize them when they are no longer
needed. Low body temperature has been shown to interfere
with normal coagulation, healing and recovery from
anesthesia. Therefore temperature is maintained
in a normal range by warming fluids and using warm
forced-air devices.
After the operation is complete, if it is possible
for the patient to breathe without assistance, the
anesthesiologist will reverse the effects of muscle
relaxants and anesthetics and remove the endotracheal
tube. If the patient requires continued ventilatory
support, the anesthesiologist will leave the tube
in. In either event, depending on the intensity
of the postoperative care required, the anesthesiologist
transports the patient to either the postoperative
care unit or to an intensive care unit. During this
recovery period, the anesthesiologist administers
drugs to relieve pain, control blood pressure and
stabilize organ function.
In essence the anesthesiologist provides continuous
medical care before, during and after operations
to permit the surgeon to make sometimes quite challenging
anatomical changes that could otherwise cause substantial
threats to the patient’s survival. Constant
research and attention to safety has led to a 10-fold
reduction in anesthesia-related deaths over the
past few decades, despite the increase in more challenging
operations and in the number of older and sicker
patients.
How Do Anesthesiologists Track
and Correct Problems With the Quality of Patient Care?
major part of the practice on anesthesiology involves
anesthesiologists tracking and correcting problems
during each anesthetic. Adding up all of the problems
that occur in each anesthetic and making sense of
all of this information is essential to making improvements
in the quality and safety of all anesthetics.
Over the past several decades, the improvements in
care provided by anesthesiologists have resulted in
an extraordinary decrease in complications and death
associated with anesthesia. This has occurred due
to improvements in the techniques and drugs available
and to a careful, ongoing evaluation and correction
of problems associated with anesthetics. ASA and the
Anesthesia Patient Safety Foundation (APSF) have been
leaders in promoting and improving safe practices
and better methods of monitoring patient well-being.
One way that safety has been improved by these organizations
is by establishing consistent high standards of practice
and guidelines to practice that are based on the best
science available. Other improvements have resulted
from the analysis of reports of problems and “near
misses” from operating rooms around the country.
This type of central reporting is important in providing
an early warning about problems that might occur too
infrequently for individual organizations to detect
them. Such evaluations lead to changes in practice
as do the development of better ways to measure how
well patients are doing during operations. For example,
20 years ago, anesthesiologists began to use devices
that continuously measure oxygen levels in the blood.
As a result, dangerous decreases in oxygen level are
detected rapidly and can be corrected quickly. This
has greatly reduced the occurrence of brain damage
due to lack of oxygen.
Evaluation of each anesthetic given helps to discover
problems. When the results are compared between individuals
and institutions, important but infrequent problems
are recognized. Actions taken to reduce them improves
safety. Much of the theory of how to measure and improve
safety and quality comes from a variety of sources,
including industry, agriculture and statistics. Theories
on safety and quality are very dependent on the work
of W. Edwards Deming, the individual most responsible
for the development of the concept of continuous quality
improvement. The ways that hospitals and individual
departments of anesthesiology measure quality and
outcomes are based primarily on methods promoted by
ASA and the Joint Commission on Accreditation of Healthcare
Organizations. Many governmental regulations also
are intended to improve safety. When organizations
pool their data, they are more likely to recognize
previously unknown threats. When this happens, they
are better able to work together to plan for ways
to improve safety. Some issues that limit effective
pooling of data include concerns for privacy, liability
and the need for agreement on how to best collect
and analyze the information efficiently.
Regardless of the health care organization, some methods
of evaluating and correcting problems have become
common. Every time a patient is anesthetized, problems
associated with the anesthetic are recorded, usually
on a quality report form. The kinds of problems that
are reported include difficulty managing ventilation,
blood pressure problems, equipment malfunctions and
other unexpected difficulties or inefficiencies. The
number of possible problems tracked on quality report
forms varies from a dozen or so to several dozen.
The data on these forms are usually transferred to
a computer database. From this database, one can analyze
the problems, the types of patients having them, the
locations in which they occurred, the types of operations
during which they occurred, the physicians and nurses
involved and the way in which each of these relates
to one another. By analyzing trends and the causes
of the problems, solutions are developed to reduce
their occurrence. Such solutions may involve purchasing
new or better equipment, changing medical practices
or improving the training of members of the operating
room team.
Anesthesiologists have been leaders in the field of
safety and quality improvement. Research done by anesthesiologists
in improving outcomes has become a model for patient
safety.
| |
|
Jerry A. Cohen, M.D., is Associate Professor
of Anesthesiology, Department of Anesthesiology,
University of Florida, Gainesville, Florida.
He is the ASA Director from Florida and Chair
of the ASA Section on Professional Standards. |
|
|