Small Bowel Obstruction and Gas in the Portal System

86 yo CF was admitted from NH with a one week history of loose stools, and a 4-day history of nausea and vomiting. She also c/o distended abdomen with crampy abdominal pain. For the last two days, attempts have been made at managing her at the nursing home with IV fluids and anti-emetics. She had no urinary complaints.

PMH:
CAD, CHF, HTN, PUD, osteoporosis and macular degeneration

PSH:
Hysterectomy and placement of a permanent pacemaker

Medications:
KCL, Lipitor, Lisinopril, Protonix, aspirin, Coreg, Digitek, and Lasix

Allergies:
She has reportedly multiple allergies including PCN, Altace, Prevacid, Norvasc, Ceclor, and Meclomen

Physical examination:
VS 36-74-36-158/88
Appears acutely ill, she is in moderate distress and lethargic but arousable
Chest: bibasilar rhonchi, tachypneic
CVS: Clear S1S2
Abdomen: Distended and tympanic. She has generalized epigastric tenderness with mild guarding and rebound. Bowel sounds are hyperactive. Rectal exam showed heme negative stool.

What do you think is going on?
Small bowel obstruction (SBO) vs. large bowel obstruction (LBO)
Dig toxicity
Ischemic colitis
Gastroenteritis
C.diff.

What labs would you order?
CBCD, CMP, Dig level, UA, Stool WBC, C&S, O&P, KUB
What about a CT of the abdomen?

Labs:
WBC 16.4, hemoglobin 13, platelets were 269,000. She had 86% PMN, and no bands. Her white count at earlier this morning was 10.8.


CBCD, note the elevated WBC with 86% PMN and the appearance of bands (36%) several hours later


BMP in SBO - note the development of metabolic acidosis

Amylase and lipase are normal. Urinalysis is normal. Dig level is 1.2.

Abdominal X-rays - 3 views:


AXR: Lateral view, SBO, dilated small bowel loops, one air-fluid level (right). Pacemaker; Air-fluid level close-up


SBO, multiple dilated small bowel loops. Close-up: note the valvulae crossing the lumen from side to side; in LBO the haustrae cross only half-way

Radiology report:
Very prominent gaseous distention of multiple loops of small bowel overlying the lower abdomen and pelvis. Associated air fluid levels are noted on decubitus films. These findings are suspicious for SBO, with associated prominent gastric distention and large air fluid level overlying stomach. No obvious free air is identified. There is severe dextroscoliosis.

What happened?
Patient was admitted to the intensive care unit. She also had CT scan of the abdomen and pelvis in the ER.
Working diagnosis was bowel obstruction.

Before the patient went to CT scan, a NG was put and 1200 cc of fecal like material was drained, and then about 400 cc of contrast was passed per NG tube prior to CT.

What happened next?
CT scan showed gas in the portal system.


CT chest and abdomen: Note the metallic reflections in the heart due to the pacemaker wires. Calciffication in the aorta, contrast in the stomach


Gas in the portal system. Note also the severe scoliosis.


Gas in the portal system. Dilated stomach half-filled with contrast


Dilated small bowel loops with air-fluid levels

Radiology report of CT abdomen and pelvis with IV and oral contrast:

Severe dextroscoliosis, resulting in distortion of upper abdominal anatomy. There is associated tortuosity and calcification of the abdominal aorta. A NG tube terminates within the stomach, which is distended with contrast proximally. There is very prominent distention of multiple loops of small bowel, with fluid distention more proximally and with fecal material being suggested more distally. The findings are suspicious for severe distal SBO. No abnormal colonic distention is seen. No intra-abdominal free air or generalized ascites is seen. There is extensive gas in the portal system. The uterus is presumed surgically absent.

Impression:
1. Findings suspicious for high grade distal SBO. Surgical consult recommended.
2. No free air or generalized ascites.
3. Extensive gas in the portal system, of uncertain etiology.

Note: CT abdomen was initially read as pneumobilia (gas in the biliary system) which was later corrected. Pneumonilia is central in distribution as opposed to the peripheral distribution of the gas in the portal system seen in this patient.

A surgical consult was called urgenlty. The preoperative diagnosis of small bowel obstruction was confirmed during the laparotomy.The operation consisted of exploratory laparotomy and adhesiolysis.

Upon entering the abdomen, multiple loops of densely adherent and distended small bowel loops were encountered. By tracing the bowel down to the area of the ileocecal valve, the surgeon found dense adhesions which originated from the pelvis. These were lysed, after which the loops of bowel were then seen to decompress themselves in the distal bowel and into the cecum itself. The bowel appeared to be dusky but viable upon closer inspection. It was noted that the patient's mesentery pulsations were quite diminished, although no ischemia was noted.

After surgery, the patient improved and was discharged to the nursing home.

Final diagnosis:
Small bowel obsctruction (SBO) secondary to adhesions and gas in the portal system

What did we learn from this case?
Bowel obstruction is on top of the list in elderly patients with abdominla pain and N/V, especially with a history of previous abdominal surgery.

CT abdomen is important in the diagnosis of SBO. Consult a surgeon early.

Comparison of small bowel obstruction (SBO) and LBO features :
Small bowel------------------------Large bowel

Bowel diameter (cm)
>3 and <--------------------------- >5

Position of loops
Central-----------------------------Peripheral

Number of loops
Many-------------------------------Few

Bowel markings
Valvaulae---------------------------Haustra
(all the way across)-----------------(partially across)