The diagnosis of acute abdomen in a patient receiving intensive care may be delayed when certain risk factors are present. Delay in diagnosis and surgical intervention can result in a significant increase in mortality. The authors are from the Mayo Clinic.


Causes for the acute abdomen in study population:

(1) ischemic bowel (32%)

(2) diverticulitis

(3) appendicitis

(4) cholecystitis

(5) perforated peptic ulcer

(6) complication of previous surgical procedure


Surgical delay was defined as surgery > 48 hours after the first clinical sign of acute abdomen (abdominal pain, peritoneal signs, radiographic ileus, radiographic free air in the in the abdomen, unexplained leukocytosis, or lactic acidosis.


Risk factors for delayed surgery:

(1) therapy with antibiotics

(2) therapy with opioids

(3) absence of peritoneal signs

(4) altered mental status

(5) mechanical ventilation

Risk Factor for Delayed Surgery

Odds Ratio

95% CI

p value

antibiotic therapy


1.4 – 16.7


opioid therapy


1.2 – 21.3


absence of peritoneal signs


1.6 – 18.5


altered mental status


1.7 – 20.2


mechanical ventilation


1.4 – 36.0


from Table 3, page 1189


A patient with one or more of these risk factors should be monitored more closely for development of an acute abdomen with prompt surgical intervention.


Risk factors for mortality in a patient with delayed surgery:

(1) ischemic bowel

(2) renal failure (serum creatinine > 2 mg/dL)

(3) APACHE III score > 60 on day 1


NOTE: It would seem that delay in surgery and increased mortality is higher in patients with multi-organ failure. Since 10% of patients had a history of recent surgery or intra-abdominal procedure, I might watch such patients more closely.


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