วันพุธที่ 25 กุมภาพันธ์ พ.ศ. 2569

Postgastrectomy Complications

Complications after Gastric Resection (Postgastrectomy Complications)

1. บทนำ (Clinical significance)

การผ่าตัดกระเพาะอาหาร (gastrectomy) ทั้งแบบ partial และ total gastrectomy ที่มี reconstruction เช่น Billroth I, Billroth II, Roux-en-Y, esophagojejunostomy สามารถทำให้เกิดความผิดปกติของ GI physiology และภาวะแทรกซ้อนเฉพาะหลังผ่าตัดได้
แม้ปัจจุบันอุบัติการณ์ลดลง แต่ historical data พบว่าผู้ป่วยประมาณ 25% มีอาการหลังผ่าตัด และ 2–5% มีอาการรุนแรงหรือ disabling

ควรสงสัยภาวะแทรกซ้อนในผู้ป่วยที่มี:

  • persistent epigastric pain
  • nausea/vomiting
  • early satiety
  • bloating
  • diarrhea
  • weight loss

2. Postgastrectomy Anatomy & Pathophysiology (Clinical concept)

ความผิดปกติหลังผ่าตัดขึ้นกับ:

  • extent ของ gastric resection
  • type ของ reconstruction
  • pylorus removal/bypass
  • vagal denervation
  • loss of gastric reservoir function
  • altered gastric emptying & bile reflux

3. Diagnostic Approach (Practical ED/Clinical Algorithm)

3.1 Initial imaging

First-line investigation:
➡️ Abdominal CT scan (most patients with significant GI symptoms)

Situation-based evaluation

Clinical presentation

Suggested investigation

Acute abdomen (fever, tachycardia, peritonitis)

CT abdomen (rule out leak/abscess)

Acute obstruction (vomiting, pain)

CT ± Upper GI series

Chronic dysmotility

CT + Endoscopy → Gastric emptying study

Suspected dumping

Clinical diagnosis ± gastric emptying / OGTT

4. Anastomotic Complications (High-yield for surgeons & ED)

4.1 Anastomotic Leak

Timing

  • Most common: POD 7–10

Clinical clues

  • Fever
  • Unexplained tachycardia (important early sign)
  • hypotension
  • abdominal pain
  • acute abdomen

Diagnosis

  • CT: pneumoperitoneum, extraluminal contrast, fluid collection, abscess
  • Water-soluble contrast study (Gastrografin) if needed

Management (Stepwise)

1.       Broad-spectrum antibiotics (immediately)

2.       CT-guided percutaneous drainage (if contained, stable)

3.       Surgery if:

o   hemodynamic instability

o   diffuse contamination

o   failed nonoperative management

4.2 Duodenal Stump Leak (เฉพาะ Billroth II / Roux-en-Y)

  • Life-threatening complication
  • Goal: sepsis control + drainage
  • May require tube duodenostomy + operative drainage

4.3 Anastomotic Stricture

Common in:

  • Billroth II (gastrojejunostomy scarring)
  • Roux-en-Y (6–20%)

Symptoms

  • Gastric outlet obstruction
  • Nonbilious vomiting
  • Bloating, early satiety

Diagnosis

  • Upper GI series (best)
  • Endoscopy + biopsy (rule out recurrence cancer)

Treatment

  • Endoscopic dilation (first-line)
  • Stenting (selected cases)

5. Mechanical Obstructive Complications (Exam favorite)

5.1 Afferent Loop Syndrome (Billroth II)

Pathophysiology

Obstruction of duodenojejunal limb proximal to GJ anastomosis

Clinical

  • Acute: severe abdominal pain + vomiting → surgical emergency
  • Chronic: postprandial pain + projectile bilious vomiting (relieves pain)

Diagnosis

  • CT: dilated afferent loop (diagnostic)

Treatment

  • Surgical revision / conversion to Roux-en-Y
  • Braun enteroenterostomy (decompression option)

5.2 Efferent Loop Syndrome

  • Distal jejunal obstruction
  • Symptoms: gastric outlet obstruction + bilious vomiting
  • Treatment: surgical correction

5.3 Internal Hernia

High risk after:

  • Roux-en-Y
  • Billroth II

Presentation

  • Acute abdominal pain ± vomiting
  • Closed-loop obstruction risk → bowel infarction

Diagnosis

  • CT scan (key)

Management

➡️ Early surgery (urgent)

5.4 Jejunogastric Intussusception (Rare but severe)

  • Acute bloating + bloody vomiting
  • Seen on CT / endoscopy / UGI series
  • Treatment: surgical resection + revision anastomosis

6. Marginal Ulcer (Post-gastrojejunostomy ulcer)

Location

  • Jejunum distal to anastomosis (most common)

Risk factors

  • NSAIDs
  • H. pylori
  • retained antrum
  • incomplete vagotomy
  • gastrinoma (ZES)

7. Motility-related Postgastrectomy Syndromes (Very high yield)

7.1 Dumping Syndrome

Pathophysiology

Rapid gastric emptying of hyperosmolar chyme → fluid shift + vasoactive hormones
(common after pylorus bypass/destruction)

Types

Early dumping (15–30 min post-meal)

  • nausea
  • cramping
  • diarrhea
  • diaphoresis
  • palpitations
  • flushing

Late dumping (1–3 hr post-meal)

  • reactive hypoglycemia (postprandial insulin surge)

Diagnosis

  • Clinical (primary)
  • Gastric emptying study / glucose challenge (supportive)

Treatment (Stepwise)

1.       Dietary modification (first-line)

o   small frequent meals

o   high protein/fiber

o   low simple carbohydrates

o   separate liquids from solids

2.       Octreotide (severe cases)

3.       Reoperation (rare, refractory)

7.2 Postvagotomy Diarrhea

  • Occurs ~30% after truncal vagotomy
  • Mechanism: bile salt malabsorption → colonic secretion
  • Treatment:
    • Usually self-limited
    • Cholestyramine (persistent cases)

7.3 Slow Transit Disorders (Important differential of chronic symptoms)

A. Gastric Stasis (Postgastrectomy gastroparesis)

Symptoms:

  • early satiety
  • postprandial fullness
  • vomiting undigested food
  • weight loss

Diagnosis:

  • Gastric emptying study (gold standard)
  • Endoscopy (rule out obstruction, bezoar)

Treatment:

  • Small frequent meals
  • Prokinetics: metoclopramide, erythromycin
  • Reoperative surgery (refractory)

B. Alkaline Reflux Gastritis (Bile reflux)

Clinical

  • Burning epigastric pain
  • chronic nausea (worse after meals)

Diagnosis

  • Exclusion diagnosis
  • Endoscopy: gastritis
  • Technetium biliary scan (bile reflux)

Treatment

  • Limited medical efficacy
  • Surgical diversion (e.g., Roux-en-Y)

C. Roux Stasis Syndrome

Occurs after Roux-en-Y reconstruction
Mechanism: dysmotility of Roux limb (reverse peristalsis)

Symptoms:

  • vomiting
  • epigastric pain
  • weight loss

Diagnosis:

  • UGI series + gastric emptying study
  • Dilated flaccid Roux loop

Treatment:

  • Prokinetics
  • Surgical revision (refractory)

8. Gallstones after Gastrectomy

Mechanism

  • Cholestasis from:
    • vagotomy
    • weight loss
    • lymph node dissection
    • altered physiology

Prevention

  • Ursodeoxycholic acid (reduces incidence)

9. Long-term Complications of Gastric Remnant

9.1 Recurrent Peptic Ulcer

Surgical causes

  • Retained gastric antrum → hypergastrinemia
  • Incomplete vagotomy → hyperacidity

Workup

  • Fasting serum gastrin
  • Secretin test (differentiate ZES vs retained antrum)
  • Evaluate NSAIDs, H. pylori, malignancy

9.2 Gastric Remnant Cancer (Stump carcinoma)

Key facts

  • Risk increases 15–20 years post surgery
  • Incidence: ~0.8–8.9%
  • Common site: near gastrojejunostomy

Surveillance

  • Not mandatory routinely
  • Consider endoscopy ≥15–20 years post-gastrectomy
  • Urgent endoscopy if new GI symptoms

10. Nutritional Deficiencies (Must not forget in follow-up)

Common deficiencies after gastrectomy:

  • Iron deficiency
  • Vitamin B12 deficiency
  • Folate deficiency
  • Fat-soluble vitamins
  • Calcium/Vitamin D

Mechanisms:

  • reduced intrinsic factor
  • malabsorption
  • rapid transit
  • decreased intake

11. Red Flags in Postgastrectomy Patient (Clinical Pearls for ED/Surgeons)

รีบ evaluate ด้วย CT หากพบ:

  • unexplained tachycardia (early leak sign)
  • acute abdominal pain post-op
  • bilious vomiting + severe pain (afferent loop obstruction)
  • persistent vomiting + weight loss (stasis/stricture)
  • late hypoglycemia after meals (late dumping)

12. High-Yield Summary (Exam & Clinical Practice)

  • First-line imaging: CT abdomen
  • POD 7–10 + tachycardia → suspect anastomotic leak
  • Post-meal vasomotor symptoms → dumping syndrome
  • Bilious projectile vomiting relieved by vomiting → afferent loop syndrome
  • Chronic nausea + bile reflux pain → alkaline gastritis
  • 15–20 years post gastrectomy → risk of remnant gastric cancer
  • Persistent diarrhea post vagotomy → consider postvagotomy diarrhea (cholestyramine)
ที่
ป้ายกำกับ:

ไม่มีความคิดเห็น:

แสดงความคิดเห็น

สมัครสมาชิก: ส่งความคิดเห็น (Atom)