We'll move on to our next case now.
We have a 69-year-old woman
with coronary artery disease
who was admitted to the ICU for
septic shock due to pneumonia.
She has started on broad spectrum
antibiotics and norepinephrine.
On hospital day 3, she developed
sudden-onset crampy abdominal pain
And a few hours later,
she develops hematochezia.
Vitals are notable for blood
pressure of 89/55 and a pulse of 110
On abdominal exam, she has tenderness
on the left side without rebound or guarding.
Her rectal exam confirms bright red blood.
Labs show hemoglobin of 8 g/dL, leukocyte
count of 20,000/uL and lactate of 8 mmol/L.
CT of the abdomen shows edema
and thickening of the ascending colon.
So what is the most likely diagnosis?
So we'll point out that she has new abdominal pain
and bright red blood per rectum or hematochezia
and she's a patient with
Her physical exam localizes
to the left side of her abdomen
with confirmed hematochezia on rectal exam.
And she has a high lactate
with a high white count.
In addition, her CT imaging is
concerning and we'll go over that next.
So, she most likely has colonic ischemia.
This is what occurs when there is lack of perfusion
to the bowel wall leading to an infarct of the bowel.
Recall that this tends to occur In an
areas with limited collateral circulation.
So we'll have to go back to
our anatomy here on the right
and remember that there are two
areas that we call watershed areas
where there is limited collaterals flow
between the large vessels that supply the colon.
So the first area is the splenic flexure, which is
the area between the SMA and the IMA
The second area that’s prone to develop
with ischemia is the rectosigmoid junction
which is between the IMA and
the hypogastric arterial system.
So patients may present with
sudden crampy abdominal pain.
They often have hematochezia,
an urgent desire to defecate
and they may have elevated
lactate and elevated white counts.
The diagnosis is made mostly clinically however
he may also do CT abdomen with IV contrast,
or colonoscopy if the
diagnosis remains unclear.
Treatment consists of
primarily supportive care,
doing bowel rest to prevent
further ischemia to the area,
and surgical resection if
bowel necrosis has occurred
or if the patient has
now developed peritonitis.
So there are common risk factors
for developing colonic ischemia.
The number one factor is atherosclerotic disease
which already limits blood flow to the area,
strenuous physical activity which can
divert blood flow to other areas of the body,
vasoconstricting medications or drugs
that also prevent blood flow to the area.
or thrombophilia which is either inherited or
acquired ability to develop blood clots.
So now let's return to our case.
We have a 69-year-old woman with
new-onset abdominal pain and hematochezia
with hemodynamic instability.
Her exam and labs are concerning
for some intraabdominal pathology
and her CT imaging shows findings
consistent with bowel ischemia.
So the most likely diagnosis
here is colonic ischemia.
Thank you very much for your attention.