Page 1559 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

1078 PART 10: The Surgical Patient

TABLE 113-1 Common Causes of Acute Abdominal Pain in North American Adults
• Complications occur frequently in the postsurgical ICU patient;
“stable vital signs” does not imply clinical stability. Inflammatory disorders and perforations (eg, cholecystitis, diverticulitis, perforated peptic
• Postoperative residual or recurrent intra-abdominal sepsis may ulcer, pancreatitis, trauma, infected dialysis catheter) with local or diffuse peritonitis
not be obvious clinically or radiographically; cardiorespiratory or Obstructions
other organ dysfunction should prompt a search for the source that Biliary colic
will require resuscitation, antibiotics, and source control Renal colic
• The treatment of the febrile postsurgical patient is not simply the Intestinal obstruction
administration of antibiotics.
• Acalculous cholecystitis is a treacherous disease that requires Vascular
urgent treatment; definitive diagnosis is not always possible or Mesenteric ischemia
necessary before treatment. Ruptured abdominal aortic aneurysm
• Abdominal wall tissue loss or tension may preclude fascial closure Intra-abdominal or retroperitoneal hemorrhage
at laparotomy. ICU staff must understand and manage postopera- Urologic or gynecologic disorders
tively techniques to protect intestinal integrity and cardiopulmo-
nary function, such as temporary closure and vacuum dressings. Medical disorders (eg, lupus serositis, sickle cell crisis, myocardial infarction, pulmonary embolus)

at another hospital should have immediate and continued surgical
attendance at the new site.
Patients with an “acute abdomen” present challenging problems for
surgeons and intensivists. The term acute abdomen refers to a patient 3. Serum amylase and lipase determinations, and imaging with abdom-
whose chief presenting symptom is the acute onset of abdominal pain. inal CT and ultrasound, should be included in the initial tests for
The majority of these patients present in the emergency department patients with acute abdominal problems when physical examination
and need operation but do not require treatment in an ICU. However, is unreliable. If these tests rule out pancreatitis, ruptured aneurysm,
the small percentage of patients who require ICU admission consti- and retroperitoneal hemorrhage, the patient will often need abdomi-
tute a significant fraction of the surgical ICU patients in most general nal exploration to manage intestinal perforation, inflammation,
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hospitals. Furthermore, the intensivist must be aware that an ICU obstruction, or ischemia (see Figs. 113-1 and 113-2).
patient may develop an acute abdominal emergency while being treated 4. Laparoscopy may help, particularly in patients suspected of having
for another condition. ischemic bowel or acalculous cholecystitis. 2-4
In this chapter, we will first discuss the approach to the ICU patient 5. Obtain information from family members, previous admissions,
who develops abdominal pain while undergoing treatment for some and other hospitals and caregivers regarding medical conditions and
other disorder. The bulk of the chapter, however, will be directed to the medications.
patient with known intra-abdominal sepsis (IAS) who requires intensive
care. Emphasis will be placed on the early diagnosis of intra-abdominal There is no single approach to the ICU patient who develops an
septic complications. acute abdomen, and simply determining that the patient has an acute
abdomen can challenge experienced clinicians. Successful management
EVALUATION OF ACUTE ABDOMINAL PAIN
IN THE INTENSIVE CARE UNIT PATIENT
The diagnosis of abdominal pain depends heavily on an accurate his-
tory and a complete physical examination. Both of these sources of
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data may be severely limited in the ICU patient. History may be unob-
tainable because of intubation or a decreased level of consciousness.
Physical examination is made difficult by cannulas and dressings, and
compromised further by the effects of medications such as analgesics
and corticosteroids. Abdominal pain itself may be masked by narcot-
ics or other painful disease processes. Some physical signs, such as the
absence of bowel sounds, which would be considered significant in an
otherwise well patient, may not be significant in an ICU patient, in
whom multiple extra-abdominal causes of ileus may be present. Hence,
in the ICU setting, it is rare that an abdominal complaint comes to light
because the patient complains of abdominal pain; rather, the physician
usually must infer its presence on the basis of nonspecific findings such
as unexplained sepsis, hypovolemia, and abdominal distention.
Table 113-1 shows some common causes of acute abdominal pain in
North American adults. Rather than describe a complete algorithm to
diagnose these conditions in ICU patients, we will list important principles.
1. Evaluate the patient in the context of the underlying disorder(s). For
example, sudden, severe abdominal pain in a patient with congestive
heart failure secondary to myocardial infarction is more likely to be
due to mesenteric ischemia than to renal colic.
2. Use surgical consultants liberally. A patient with significant unex-
plained abdominal pain lasting more than 4 hours should be seen FIGURE 113-1. CT scan demonstrates massive amounts of free air under the diaphragm.
by a surgeon. A patient transferred to the ICU following operation The patient developed septic shock from a perforated gastric ulcer.

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