Chapter 27
- Anesthetic Implications of Concurrent Diseases
- Michael F. Roizen
- Lee A. Fleisher
This chapter reviews conditions requiring special preoperative
and preprocedure evaluation and/or intraoperative or procedure management, or postprocedure
care. Patients undergoing surgery move through a continuum of medical care to which
a primary care physician, an internist or pediatrician, an anesthesiologist, and
a surgeon, radiologist, or obstetrician-gynecologist contribute to ensure the best
outcome possible. No aspect of medical care requires greater cooperation among physicians
than does performance of a surgical operation or complex procedure involving multiple
specialists and the perioperative care of a patient. The importance of integrating
physicians' expertise is even greater within the context of the increasing life span
of our population.[1]
As the number of the elderly
and the very old (those older than 85 years) grows, so does the need of surgical
patients for preoperative consultation to help plan for comorbidity and multiple
drug regimens, knowledge of which is crucial to successful patient management. At
a time when medical information is encyclopedic, it is difficult, if not impossible
for even the most conscientious anesthesiologist to keep abreast of the medical issues
relevant to every aspect of perioperative or periprocedure patient management. This
chapter reviews such issues.
As with "healthy" patients (also see Chapter
25
), it is the history and physical examination that most accurately predict
not only the associated risks but also the likelihood that a monitoring technique
or change in therapy will be beneficial or necessary for survival. This chapter
emphasizes instances in which specific information should be sought in history taking,
physical examination, or laboratory evaluation. Although controlled studies designed
to confirm that optimizing a patient's preoperative or preprocedure physical condition
would result in lower morbidity have not been performed for most diseases, it is
logical to assume that such is the case. Studies showing the benefits of optimizing
specific preprocedure conditions are highlighted. The fact that such preventive
measures would cost less than treating the morbidity that would otherwise occur is
an important consideration in a cost-conscious environment.
Recent data indicate that minimally invasive procedures such as
cataract extraction, magnetic resonance imaging (MRI), or diagnostic arthroscopy
(see Table 25-6
in Chapter
25
), performed in conjunction with the best current anesthetic practices,
pose no greater risk than daily living does and thus might not be considered an opportunity
for special evaluation. Nonetheless, preanesthetic and preprocedure evaluations
were found to provide information that led to changes in health care plans for more
than 15% of all American Society of Anesthesiologists (ASA) class I and II patients
(and for >20% of all patients in general) at the University of Florida (Gibby
GL et al., personal communication). Although these changes in care plans were attributable
to data found by history taking and observation (the most common being gastric reflux,
diabetes mellitus requiring insulin, asthma, and suspected difficult intubation),
no data show that patient outcome was improved by such changes. Nevertheless, logic
caused practitioners to alter plans for such patients in ways that would delay operating
room schedules and increase costs. Examples would be administering a β-adrenergic
blocking drug, aspirin, or a statin (or any combination) the night before rather
than delaying surgery to do so on the morning of surgery; administering a histamine
type 2 (H2
) antagonist 1 to 2 hours before and an oral antacid immediately
before entry into the operating room; ensuring the availability of equipment to measure
blood glucose levels; obtaining a history of the patient's diabetic course and treatment
from the primary care doctor, as well as from the patient; and performing a fiberoptic
laryngoscopic examination or procuring additional skilled attention. Thus, even
if preoperative and preprocedure evaluation might not alter the outcome in an important
way, its ability to decrease cost by reducing unwarranted laboratory testing and
delays in obtaining treatment and equipment perceived to be beneficial (and medicolegally
required) would be substantial and would warrant its use.
Examples of determining the costs of such benefits can be found
in Chapter 25
or in this
chapter in the section on preoperative and preprocedure preparation of patients with
cardiovascular disease. The following conditions are discussed in this chapter:
- Diseases involving the endocrine system and disorders of nutrition
- Diseases involving the cardiovascular system
- Disorders of the respiratory and immune system
- Diseases of the central nervous system (CNS), neuromuscular diseases, and
mental disorders
- Diseases involving the kidney, infectious diseases, and disorders of electrolytes
- Diseases involving the gastrointestinal (GI) tract or the liver
- Diseases involving hematopoiesis and various forms of cancer
- Diseases of aging or those that occur more commonly in the aged, as well
as chronic and acute medical conditions requiring drug therapy (also see Chapter
62
).
