Subinternship Surgery · Year 4 · from Subinternship Surgery
Case 1: Small Bowel Obstruction with Strangulation
Patient Presentation
Demographics: 68-year-old female
Chief Complaint: Severe abdominal pain, nausea, and vomiting for 12 hours
History of Present Illness: Mrs. Patterson presents to the emergency department with acute onset of severe, crampy abdominal pain that began 12 hours ago. She has had multiple episodes of bilious vomiting and has not passed gas or stool since symptom onset. The pain has become constant over the past 4 hours and is now localized to the left lower quadrant. She has a history of open hysterectomy 15 years ago for uterine fibroids.
Past Medical History:
- Hypertension
- Type 2 diabetes mellitus (on metformin)
- Hyperlipidemia
- Prior abdominal surgery (TAH-BSO, 2009)
Physical Examination:
- Vitals: T 38.4C, HR 118, BP 98/62, RR 22, SpO2 96% RA
- General: Appears distressed, diaphoretic
- Abdomen: Distended, tympanic, diffuse tenderness with focal peritoneal signs in left lower quadrant, well-healed Pfannenstiel scar
- Bowel sounds: High-pitched, hyperactive
Laboratory Studies:
- WBC: 18,200 with left shift (85% neutrophils)
- Lactate: 4.8 mmol/L (elevated)
- BUN/Cr: 28/1.4 (baseline 1.0)
- Glucose: 245 mg/dL
- Lipase: Normal
Clinical Questions
- What imaging study should be ordered, and what findings would you expect?
Recommended Imaging: CT abdomen/pelvis with IV contrast (oral contrast optional given clinical picture)
Expected Findings in SBO: | Finding | Significance | |---------|--------------| | Dilated small bowel (>3cm) | Confirms obstruction | | Transition point | Identifies location of obstruction | | Small bowel feces sign | Suggests complete obstruction | | Decompressed distal bowel | Confirms complete obstruction |
Findings Concerning for Strangulation: | Finding | Significance | |---------|--------------| | Closed-loop configuration | Two adjacent transition points - HIGH RISK | | Bowel wall thickening | Suggests edema/ischemia | | Mesenteric haziness | Inflammatory changes | | Reduced/absent wall enhancement | Suggests ischemia | | Pneumatosis intestinalis | Air in bowel wall - LATE FINDING | | Portal venous gas | OMINOUS - indicates necrosis |
This patient's CT shows: Closed-loop obstruction in the left lower quadrant with a transition point at a band adhesion, surrounding mesenteric stranding, and reduced enhancement of the involved segment consistent with strangulated small bowel obstruction.
- This patient has signs concerning for strangulation. What are the clinical indicators of strangulation in SBO?
Clinical Signs of Strangulation:
| Category | Finding | Present in This Patient | |----------|---------|------------------------| | Vital signs | Tachycardia, hypotension | Yes - HR 118, BP 98/62 | | Pain | Constant (not colicky), severe | Yes - became constant | | Exam | Focal peritoneal signs | Yes - LLQ peritonitis | | Fever | Temperature >38C | Yes - 38.4C | | Labs | Elevated lactate | Yes - 4.8 | | Labs | Leukocytosis | Yes - 18,200 | | Labs | Metabolic acidosis | Check ABG |
Assessment: Multiple clinical indicators suggest strangulation - this patient requires EMERGENT surgical intervention.
- What are the key differences between operative and non-operative management of SBO?
Management Algorithm:
| Feature | Non-Operative Management | Operative Management | |---------|-------------------------|---------------------| | Obstruction type | Partial | Complete | | Signs of strangulation | Absent | Present | | Closed-loop | No | Yes | | Peritoneal signs | No | Yes | | Prior response | History of resolving with conservative Rx | First presentation or failed conservative | | Time limit | 48-72 hours trial | Immediate if strangulated |
Non-Operative Management Components:
- NPO status
- Nasogastric tube decompression
- IV fluid resuscitation
- Serial abdominal exams (q4-6h)
- Water-soluble contrast study (Gastrografin) - both diagnostic and therapeutic
This Patient: Meets criteria for emergent surgery due to signs of strangulation.
- Outline your surgical consultation and communication with the OR team.
Structured Surgical Consultation (SBAR format):
Situation: "I am the sub-intern caring for Mrs. Patterson in the ED. She has a strangulated small bowel obstruction requiring emergent surgical intervention."
Background: "68-year-old female with prior TAH-BSO presenting with 12 hours of SBO symptoms. CT shows closed-loop obstruction with signs of strangulation."
Assessment: "Clinical picture of strangulation - tachycardia, hypotension, fever, peritoneal signs, lactate 4.8, leukocytosis."
Recommendation: "Patient needs emergent exploratory laparotomy. I have obtained consent, type and screen is sent, and she has large-bore IV access. Blood bank is aware. She is currently receiving volume resuscitation."
OR Communication Checklist:
- [ ] Notify charge nurse of emergent case
- [ ] Confirm equipment: laparotomy tray, bowel resection instruments, stapler available
- [ ] Anesthesia aware of hemodynamic status and aspiration risk
- [ ] Blood products: Type and crossmatch 2 units pRBC
- [ ] Antibiotic timing: Administer within 60 minutes of incision
Clinical Image
Image: Upright abdominal radiograph demonstrating multiple dilated loops of small bowel with air-fluid levels consistent with small bowel obstruction. The presence of multiple air-fluid levels at different heights within the same loop (differential air-fluid levels) suggests complete obstruction. Source: Wikimedia Commons.
Image Attribution: Upright X-ray demonstrating small bowel obstruction. Wikimedia Commons. Public Domain. URL: https://commons.wikimedia.org/wiki/File:Upright_X-ray_demonstrating_small_bowel_obstruction.jpg