Complex Cancer Cases: Caring for a Patient With Malignant Bowel Obstruction

Laura J. Zitella, MS, RN, ACNP-BC, AOCN

Suppose you have a female patient who is 52 years old with a metastatic colorectal carcinoma (mCRC) diagnosis plus peritoneal carcinomatosis. This female patient has received 7 doses of FOLFIRI, followed by cytoreductive surgery with bilateral salpingo-oophorectomy, proximal colon, and omentectomy. After developing liver and lung metastases, this patient received 4 doses of FOLFIRI plus bevacizumab (Avastin).

One week following the final dose of FOLFIRI plus bevacizumab, she underwent a 13-cm small bowel resection for closed loop obstruction and lysis for adhesions.

This patient resumed chemotherapy for mCRC with 5 cycles of FOLFOX. However, on day 5 of cycle 5, she started to experience diffuse abdominal pain and arrived at the oncology urgent care. The night before, she drank a cup of tea and immediately vomited it; she found herself unable to tolerate any food or water over the prior 12 hours. Now she is still passing flatus but has not had any bowel movements since having a normal one yesterday morning.

What does ideal care for this patient look like?

In their presentation at the 47th Annual ONS Congress, “Complex Cases and Acute Management of Emergent Complications in Cancer Care,” Laura Zitella, MS, RN, ACNP-BC, AOCN, of the University of California San Francisco, discussed how best to care for a patient presenting this potential emergency.

Upon physical exam, it was revealed that this patient had mild tenderness to epigastrium, no abdominal distention nor any comorbidities, and an ECOG performance status of 1. A check of vital signs found that her temperature was 36.9o C, heart rate was 66 bpm, respirations are 18/min, and blood pressure is 124/72 mm Hg.

In addition, her white blood count was 8.8 x 109/L, hemoglobin was low at 11 g/dL, platelets count was 285,000/mm3, blood urea nitrogen (BUN) was 10 mg/dL, and creatine was 0.84 mg/dL. In addition, her potassium levels were 4.1 mEq/L, glucose was 107 mg/dL, calcium was low at 8.1 mg/dL, sodium was 137 mEq/L, chloride was 103 mEq/L, CO2 was 23 mgEq/L, albumin was 3.4 g/dL, magnesium was 2.mEq/L, and lactate was 1.1 mmol/L.¹

As a provider, it may seem there are many different potential diagnoses, Zitella noted. For example, the patient may be experiencing delayed chemotherapy-induced nausea and vomiting, pancreatitis, peritoneal metastases, appendicitis, bowel obstruction, gastroesophageal reflux disease, or a gastric ulcer. In this case a CT scan of the abdomen would be considered appropriate, she said.

“I find that workup of abdominal symptoms can be some of the most challenging,” she explained. “So, for this patient, we went straight to CT and got a CT of the abdomen. Often that’s what you have to do [because with] these patients there are so many different abnormalities, and it is really hard to assess [their condition] without having the proper imaging.”

Surgery Considerations

The treatment algorithm for a case of malignant bowel obstruction is as follows: the provider must consider whether there is a concern for perforation, ischemia, or necrosis. If there is, then emergent surgery should be considered. If perforation, ischemia, or necrosis do not represent valid concerns, then surgery should be considered if there is evidence of closed-loop obstruction, volvulus, intussusception, or small bowel tumor.

If there is no evidence of these conditions, then a 24- to 72-hour trial of medical management should be applied. If this does not yield improvement, surgery may be considered, or, for some patients, a stent or venting gastrostomy tube may be appropriate.

The study authors noted that malignant bowel obstruction management decisions need to be highly individualized as this emergency is associated with a high rate of recurrence and morbidity.

Management Approaches

Immediate management of malignant bowel obstruction involves the “drip and suck” approach: this comprises intravenous (IV) hydration with a normal saline solution or a lactated Ringer’s solution, a correction of fluid deficit, acid-base disorders, and electrolyte abnormalities, as well as nasogastric tube decompression if the patient is nauseated or vomiting.²

Other important nursing considerations include an NPO order (nothing by mouth), monitoring urine output to assess hydration status, and serial abdominal exams. IV hydration helps prevents dehydration and correct electrolyte abnormalities, while opioids can help control pain.

Treatment with antiemetics can be useful for controlling nausea; steroids help decrease bowel edema, inflammation, and distention, while still providing antiemetic effects—dexamethasone at 4 mg/kg to 12 mg/day is recommended. Antisecretory medications can also be helpful in decreasing intestinal secretions, some treatment options include 1.5 mg of a scopolamine transdermal patch every 3 days, a histamine-2 blocker, glycopyrrolate at 0.1 mg to 0.2 mg IV 3 to 4 times daily, and octreotide at 100 mcg to 300 mcg subcutaneously 2 to 3 times per day or 10 mcg/h to 40 mcg/h continuous infusion.

Finally, a nasogastric tube decompresses the stomach. This, in turn, can help resolve the obstruction. It can also be useful in preventing gastric content form aspirating. When placing the tube, output should be monitored and replaced with IV fluids. Additionally, when the output has become greater than 1 liter, the patient should be trialed for tube removal through clamping the tube. If there are residuals greater than 100 mL in 4 hours, the obstruction may have resolved.

Back to the Case Study

A CT scan revealed that the patient was experiencing a partial small bowel obstruction with no evidence of peritoneal carcinomatosis or abdominal metastases.

“In this case, we managed her medically,” said Zitella. “This is in contrast to how she was managed earlier in the course of therapy when she did not have metastatic disease.”

Zitella added that the patient had a closed loop obstruction that was due to an adhesion.

“She was managed conservatively with bowel rest and IV fluids. NG (tube) to decompression was considered but she wasn't actively having nausea, vomiting, so we diverted as she preferred not to have it.

By her second day in the hospital, she began to feel less distended. She also had 2 bowel movements and was passing gas. She began a clear liquid diet, which she tolerated so well that she was advanced to a regular diet on the day of discharge.

Big Picture

Zitella noted that patients with a history of small bowel resection and adhesions may be at an increased risk for small bowel obstruction (SBO). This condition is often resolved spontaneous with medical management and there is currently no compelling evidence suggesting that surgery improved quality of life or survival in this patient population.

Patients with advanced cancer at an increased risk of recurrent SBO; surgically correctable caused may include closed-loop obstruction, volvulus, intussusception, and small bowel tumor.

Adhesions cannot be directly seen on any imaging studies, therefore adhesive SBO is diagnosed through exclusion: it is determined through a combination of known history of prior abdominal surgery with no alternative explanation for the obstruction.

Surgery should be considered carefully since it can be a transition to the terminal phase of the disease, it also carries the risk of additional adhesions.

“Surgery is really reserved for those cases where [there is] a keratitis or ischemia or a closed loop obstruction,” Zitella concluded, adding that, “the role of surgery [for] our patients has to be considered really carefully, because most patients who have a malignant bowel obstruction have a very poor survival and this would be a transition that this is sort of a crossroads in their in their face of care.”

Furthermore, small bowel obstruction is a diagnosis of exclusion, she reiterated to listeners. “It cannot be seen directly on any imaging adhesive,” she said. “It [involves] knowing that [patient’s] history and having no alternative explanation for the small bowel obstructions, and [understanding that], if there is advanced cancer, there's a very high risk of recurrence.”

References

1. Zitella L, Petrofsky M. Complex cases and acute management of emergent complications in cancer care. Presented at: 47th Annual Oncology Nursing Society Congress; April 27-May 1, 2022; Anaheim, CA.

2. Franke AJ, Iqbal A, Starr JS, Nair RM, George TJ Jr. Management of malignant bowel obstruction associated with GI cancers. J Oncol Pract. 2017;13(7):426-434. doi:10.1200/JOP.2017.022210.