A 64-year-old woman with ovarian cancer, emesis, and abdominal pain

Nguyet A. Nguyen and Warner K. Huh

History of present illness

A 64-year-old white woman with stage IIIC ovarian cancer presents to the emergency room with the chief complaint of abdominal pain. She reports acute onset of moderate-to-severe diffuse abdominal pain as well as progressive nausea and vomiting over the past three days. The emesis is nonbloody but bilious. The patient reports that she has not been able to tolerate any oral intake, including fluids or anti-emetics, for the past 24 hours. Her last bowel movement four days ago was loose and watery, although she reports flatus. She was diagnosed with ovarian cancer one year ago and was treated with complete surgical cytoreduction followed by six cycles of platinum- and taxane-based chemotherapy. Her medical history is otherwise unremarkable, and her surgical history is significant for a laparoscopic cholecystectomy as well as a complete hysterectomy and staging procedure as above.

She was recently seen in clinic and was noted to have a rising CA-125 and underwent a CT scan that demonstrated recurrence with diffuse intrabdominal disease including peri- toneal implants.

Physical examination

General appearance:Well-dressed thin woman in mild distress

Vital signs:

Temperature: 37.0°C Pulse: 116 beats/min

Blood pressure: 108/61 mmHg Respiratory rate: 22 breaths/min Oxygen saturation: 99% on room air HEENT:Dry mucous membranes

Cardiovascular:Regular rhythm, tachycardia, no murmurs, rubs, or gallops

Pulmonary:Symmetric chest expansion, clear to auscultation bilaterally

Abdomen:Well-healed midline scar; high-pitched bowel sounds heard in bilateral upper quadrants; moderately distended abdomen tympanic to percussion with mild tenderness diffusely; no palpable masses; no rebound or guarding

Genitourinary:Normal external female genitalia; bimanual examination reveals an intact vaginal cuff; no adnexal masses; cervix is surgically absent

Rectal:Normal sphincter tone, hemoccult negative, no masses palpated

Neurologic:Alert and oriented × 4

Laboratory studies:The patient had blood drawn for laboratory tests. A peripheral intravenous line was placed, and the patient was given a 1 L bolus of lactated Ringer’s solution, intravenous ondansetron for nausea, and intravenous morphine for pain. Laboratory results were:

Leukocyte count: 11 300/μL (normal 3500–12 500/μL) Hb: 10.2 g/dL (normal 12.0–15.5 g/dL)

Ht: 31% (normal 38–46%)

Platelets: 170 000/μL (normal 150 000–400 000/μL) Sodium (Na): 131 mEq/L (normal 135–145 mEq/L) Potassium: 3.0 mEq/L (normal 3.7–5.2 mEq/L) Chloride: 92 mmol/L (normal 96–106 mmol/L) Bicarbonate: 22 mmol/L (normal 20–29 mmol/L) BUN: 30 mg/dL (normal 7–20 mg/dL)

Creatinine: 1.4 mg/dL (baseline in clinic visit 1.0 mg/dL) Calcium: 7.8 mg/dL (normal 8.4–10.2 mg/dL)

Magnesium: 1.3 mg/dL (normal 1.8–2.5 mg/dL) Phosphorus: 2.2 mg/dL (normal 2.4–5.0 mg/dL) Imaging:Abdominal radiographs (KUB [kidney, ureter, bladder x-ray]) were obtained (Fig. 96.1a,b)

How would you manage this patient?

The diagnosis is a partial small bowel obstruction (SBO). The KUB shows dilated loops of small bowel (Fig. 96.1a) with multiple air-fluid levels in a“step-ladder”pattern and small amount of gas noted in colon (Fig. 96.1b). A nasogastric tube (NGT) was placed and 1300 mL of bilious output was imme- diately noted. On hospital day 2, the patient reported persist- ent nausea; the NGT had an additional 1200 mL of bilious output. On examination, her abdomen remained moderately distended with high-pitched bowel sounds and absent peri- toneal signs (i.e. guarding and/or rebound). She underwent a repeat KUB with diatrizoic acid (Gastrograffin®) contrast that showed a transition point in LLQ (Fig. 96.2), with a small amount of contrast beyond the transition point. By hospital day 3, the patient began to have watery bowel move- ments, and her abdominal distension and pain improved. Her NGT was removed. The patient’s diet was advanced as toler- ated, and by hospital day 5 she was discharged home on a low-residue diet.

Acute Care and Emergency Gynecology, ed. David Chelmow, Christine R. Isaacs and Ashley Carroll. Published by Cambridge University Press.

© Cambridge University Press 2015.

Small bowel obstruction

The most common causes of SBO are adhesions, malignancy, and hernias. About 80% of SBO are due to adhesions from previous surgeries and carcinomatosis or peritoneal implants from metastatic malignancies [1,2]. About 20–50% of ovarian cancer patients will develop a SBO during their disease course [1]. SBO is commonly encountered in advanced-stage or recurrent ovarian cancer patients due to their diffuse intra- abdominal disease and history of previous surgery.

Patients usually present with the classic triad of symptoms:

abdominal pain, distension, and nausea and vomiting. Patients may experience loose, watery stool due to gastrointestinal contents distal to the obstruction or may report no bowel function subsequent to the onset of symptoms. Clinical signs can include dehydration, abdominal distension, and metabolic alkalosis [1,2] with electrolyte abnormalities due to persistent emesis.

SBOs may be due to mechanical or malignant causes.

Mechanical SBO occurs when the intestinal lumen is either partially or completely obstructed by either extrinsic or intrinsic factors such as compression by adhesions or intra- luminal masses, respectively. When the lumen is obstructed, the proximal bowel becomes distended with air andfluid due to the inability of bowel contents to pass distally. Malignant SBOs occur due to dysfunctional bowel motility due to carcinomatosis or tumor implants that cause abnormal bowel peristalsis leading to accumulation of bowel contents and obstructive symptoms. In both cases, distension of the

(a) (b)

Fig. 96.1 KUB supine (a); KUB upright (b). (Images courtesy of University of Alabama at Birmingham, Department of Radiology.)

Fig. 96.2 KUB with contrast noted in partial small bowel obstruction. (Image courtesy of University of Alabama at Birmingham, Department of Radiology.)

Case 96: A 64-year-old woman with ovarian cancer, emesis, and abdominal pain

bowel lumen causes a positive feedback mechanism thereby increasing intestinal peristalsis, circulation, and hormone release to aid in digestion and absorption of bowel contents.

As such, fluid accumulates from this physiologic response causing the bowel lumen to become more distended. The distension leads to retrograde flow that manifests as nausea and vomiting [2].

The severity and timing of symptoms may aid in differen- tiating between partial and complete SBO. Partial SBOs may have a more indolent course with progressive nausea and vomiting. Up to 80% resolve with conservative management [2]. Patients with complete obstructions tend to have shorter onset of symptoms and may also have symptoms related to obstipation. Pain may be more acute and localized to one area.

Complete SBOs may also be managed conservatively; however, it is imperative to recognize signs of bowel strangulation or compromise such as fever, peritoneal signs, leucocytosis, or lactic acidosis. Expeditious surgical management may be required to avoid significant morbidity and even mortality.

Unfortunately, the clinical signs and symptoms of bowel stran- gulation often do not occur until there is irreversible bowel injury [3]. The morbidity and mortality of SBO significantly increases with bowel ischemia.

KUB films are helpful in the initial workup for SBO and can diagnose up to 66% of SBOs [1,2]. Supine KUBs will show distended bowel lumen proximal to the obstruction and may identify a transition point, while upright radiographs will illustrate air-fluid levels in a “step-ladder” pattern (Fig. 96.1a,b). A KUB may not differentiate between a partial versus complete SBO; however, the presence or absence of colonic gas may aid in the diagnosis [4]. In complete SBO, there is no passage of stool or gas beyond the obstruction resulting in the absence of colonic gas. More importantly, the presence of gas in the colon does not rule out a complete SBO;

however, the absence of colonic gas is more specific and suggests the obstruction is less likely to be partial. If the clinical picture is unclear, a CT of the abdomen and pelvis with contrast may be obtained. CT is more sensitive in diagnosing partial versus complete SBO. It may also help elucidate a transition point, identify bowel wall thickening or pneumatosis intestinalis. Bowel wall thickening occurs due to vascular congestion resulting from the transition point. As the SBO progresses, intraluminal gas may enter the injured mucosal wall leading to pneumatosis intestinalis–a latefinding in bowel ischemia. Evidence of these seriousfindings on CT may assist in surgical decision-making [5]. Although modern imaging techniques are extremely sensitive, a patient’s clinical presenta- tion and physician’s judgment should dictate management.

Resuscitation and intestinal decompression are the most important treatment goals in patients with SBOs. Patients will require intravenous access, isotonic fluid resuscitation with lactated Ringer’s or normal saline, intravenous anti-emetics and pain medication. Electrolyte repletion with sodium, potassium, and magnesium is usually required due to gastric and intestinal losses. NGT or long nasointestinal tube

decompression are used in SBO treatment to relieve bowel distension, improve nausea and vomiting, decrease risk of aspiration and also to prepare the bowel for surgery, if needed [6]. In patients who do not require surgical intervention, studies have shown that about 88% of patients have resolution of their SBO in thefirst 48 hours, and the remaining resolve within 72 hours [7].

A large systematic review has shown that the use of water-soluble contrast such as diatrizoic acid (DA) accurately predicts the need for surgical intervention and reduces the patient’s hospital stay [8]. DA is hyperosmolar and induces water-reuptake by the intestinal lumen, leading to a change in consistency and aiding in the passage of bowel contents through the partial obstruction. The advantage of using DA for radiographic contrast is due to its water solubility. If there is any bowel compromise and contrast is leaked intra- abdominally, DA may cause less damage to intraperitoneal tissue surfaces. It does not reduce the patients’ need for surgery if it is clinically indicated; however, in those who may be conservatively managed, DA significantly decreases hospital stay and interval time to surgical intervention [8].

In our case, DA was not given during the patient’s initial diagnostic KUB as the etiology and severity of the SBO is unknown and contrast may worsen a patient’s clinical status depending on severity of the SBO. Once the etiology is known, a repeat KUB with DA may be performed for thera- peutic purposes. If successful, a patient may avoid surgery;

however, if no contrast is seen past the transition point, then the likelihood the SBO will resolve without surgery is low.

Therefore, if a patient’s clinical presentation suggests bowel compromise or if medical management fails, then surgery is indicated for possible adhesiolysis or bowel resection if necessary.

Surgery is necessary in a majority of cases of SBO that fail conservative management. In malignant SBO, the decision to proceed with surgery is individualized. Life expectancy, performance status, and disease state should be taken into consideration prior to surgery, as the risk of recurrent SBO ranges from 10 to 50% [9]. A large systematic review showed no compelling evidence to support or refute surgery in patients with malignant SBO. Patients who were managed surgically generally had a better performance status and prognosis than those managed conservatively; however, surgery did not change overall survival [9]. In patients with advanced stage cancers with refractory SBO, palliative interventions including hospice and venting gastrostomy tubes may be indicated for symptomatic relief.

Key teaching points

Bowel obstructions usually present with the classic symptom triad of abdominal pain, distension, and nausea and vomiting.

Up to 80% of small bowel obstructions (SBOs) are due to adhesions and malignancy. A KUB is a simple

yet prompt diagnostic test that can aid in diagnosing SBOs; CT may aid in diagnosis if the KUB is unclear.

Patients who present with fever, leukocytosis, lactic acidosis, or signs of an acute abdomen may have bowel compromise and surgical intervention should not be delayed.

The mainstay of SBO treatment is symptom relief,fluid resuscitation, and bowel decompression. Frequent

evaluations are necessary to identify patients with bowel ischemia requiring surgery.

Complete or partial SBOs that fail conservative management usually require surgery; however, patients with malignant SBO require individualized management.

Quality of life, performance status, and prognosis may dictate whether palliative interventions should be considered in lieu of surgery.

References

1. Hayanga AJ, Bass-Wilkins K, Bulkley GB. Current management of small- bowel obstruction.Adv Surg2005;

39:1–33.

2. Soybel DI, Landman WB. Ileus and bowel obstruction. In Mulholland MW, Lillemoe KD, Doherty GM, et al., eds.

Greenfield’s Surgery: Scientific Principles and Practice, 5th edn. Philadelphia, Lippincott, Williams and Wilkins. 2010.

Available at Surgical Council on Resident Education (SCORE):http://

www.surgicalcore.org/chapter/46224.

3. Sarr MG, Bulkley GB, Zuidema GD.

Preoperative recognition of intestinal

strangulation obstruction. Prospective evaluation of diagnostic capability.Am J Surg1983;145(1):176–82.

4. Brolin RE, Krasna MJ, Mast BA.

Use of tubes and radiographs in the management of small bowel obstruction.Ann Surg1987;206(2):

126–33.

5. Balthazar EJ. CT of small-bowel obstruction.Am J Roentgenol 1994;162:255–61.

6. Fleshner PR, Siegman MG, Slater GI, et al. A prospective, randomized trial of short versus long tubes in adhesive small-bowel obstruction.Am J Surg 1995;170(4):366–70.

7. Cox MR, Gunn IF, Eastman MC, et al. The safety and duration of nonoperative treatment for adhesive small bowel obstruction.Aust N Z J Med1993;63:367–71.

8. Abbas S, Bissett IP, Parry BR. Oral water soluble contrast for the management of adhesive small bowel obstruction.Cochrane Database Syst Rev2008, Issue 3. Art. No.: CD004651.

9. Kucukmetin A, Naik R, Galaal K, Bryant A, Dickinson HO. Palliative surgery versus medical management for bowel obstruction in ovarian cancer.

Cochrane Database Syst Rev2010, Issue 7. Art. No.:CD007792.pub2.

Case 96: A 64-year-old woman with ovarian cancer, emesis, and abdominal pain