Peptic ulcer surgery
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Peptic ulcer Microchapters |
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Diagnosis |
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Treatment |
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Surgery |
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Case Studies |
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2017 ACG Guidelines for Peptic Ulcer Disease |
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Guidelines for the Indications to Test for, and to Treat, H. pylori Infection |
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Guidlines for factors that predict the successful eradication when treating H. pylori infection |
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Guidelines to document H. pylori antimicrobial resistance in the North America |
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Guidelines for evaluation and testing of H. pylori antibiotic resistance |
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Guidelines for when to test for treatment success after H. pylori eradication therapy |
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Guidelines for penicillin allergy in patients with H. pylori infection |
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Peptic ulcer surgery On the Web |
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American Roentgen Ray Society Images of Peptic ulcer surgery |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Associate Editor(s)-in-Chief: Fahad Hasan, M.D.[2] Manpreet Kaur, MD [3]
Overview
Surgery for peptic ulcer is principally indicated for the management of life-threatening complications, including upper gastrointestinal bleeding, perforation, and gastric outlet obstruction, as well as for ulcers that are refractory to maximal medical therapy or carry concern for underlying malignancy. Peptic ulcer disease has a lifetime prevalence in the general population of 5–10% and an annual incidence of 0.1–0.3%; despite a marked decline over the past three decades attributable to the discovery of Helicobacter pylori and the widespread use of proton pump inhibitors (PPIs), complications still arise in 10–20% of affected patients.[1]
Bleeding ulcers are treated first with endoscopic therapy; surgery is reserved for cases of failure or recurrence after endoscopic and angiographic management. Perforated peptic ulcer is a surgical emergency; immediate repair—preferentially by laparoscopic approach in haemodynamically stable patients—is the standard of care. Elective acid-reducing surgery (e.g., vagotomy and drainage) has been largely supplanted by modern pharmacotherapy, including optimized bismuth quadruple therapy and potassium-competitive acid blocker (vonoprazan)-based regimens for Helicobacter pylori eradication.[2]
Surgery
Indications
The principal modern indications for surgical intervention in peptic ulcer disease are summarized in the following table:
| Indication | Clinical Setting | Urgency |
|---|---|---|
| Perforated peptic ulcer (PPU) | Free intraperitoneal air, peritonitis | Emergency (immediate) |
| Upper gastrointestinal bleeding unresponsive to endoscopy and/or angioembolization | Failed therapeutic endoscopy, haemodynamic instability | Emergency |
| Recurrent bleeding after two endoscopic attempts | Rebleeding despite optimal endoscopic therapy | Urgent |
| Gastric outlet obstruction unresponsive to endoscopic dilation | Chronic scarring, pyloric stenosis | Elective/urgent |
| Refractory peptic ulcer (failed maximal medical therapy) | Non-healing ulcer despite H. pylori eradication and PPI therapy | Elective |
| Suspected or confirmed malignancy | Gastric ulcer with atypical features or positive biopsy | Elective/urgent |
| Giant ulcer (>3 cm) at high risk of complications | Large ulcers refractory to medical management | Elective |
Approximately 5% of bleeding peptic ulcers ultimately require operative intervention after failure of endoscopic and angiographic strategies.[1]
Risk Stratification
Preoperative risk stratification guides perioperative management, particularly for emergency surgery. The following validated scoring tools are applicable:
| Score | Variables | Notes |
|---|---|---|
| Boey Score | Major comorbidity (1 pt); preoperative systolic blood pressure <90 mmHg (1 pt); duration of perforation >24 hours (1 pt); range 0–3 | Bedside tool; score of 0 confers minimal risk; score of 3 associated with very high mortality. Simple and widely validated for PPU. |
| Peptic Ulcer Perforation (PULP) Score | Eight variables including age, ASA score, active malignancy, renal failure, preoperative shock, liver cirrhosis, preoperative use of NSAIDs; derived from 2,668 Danish patients with 27% 30-day mortality | Superior granularity compared with Boey score; requires laboratory values. Recommended for detailed prognostication. |
| ASA Physical Status | Overall health status assessment | Best predictor of postoperative morbidity; complements Boey and PULP scores. |
| Mannheim Peritonitis Index (MPI) | Eight intraoperative variables including source of peritonitis, degree of contamination, organ failure | Requires intraoperative data; useful for severity stratification in peritonitis. |
Surgical Options
Bleeding Peptic Ulcer
The primary goal of surgery for a bleeding peptic ulcer is hemorrhage control. The preferred operative approach depends on the location of the ulcer; it is therefore important for the surgeon to be present during upper GI endoscopy to obtain precise localization information. Surgical options are addressed under two subtypes:
- Bleeding gastric ulcer
- Bleeding duodenal ulcer
Before resorting to surgery, transarterial embolization (TAE) should be considered as a bridge or alternative in patients who rebleed after failed endoscopy, as TAE reduces the need for surgery without increasing overall mortality and is associated with fewer postoperative complications compared with immediate operative intervention.[1] Surgery is reserved for cases where both endoscopy and TAE have failed or are not feasible.
Different surgical treatment options for refractory or complicated bleeding peptic ulcer disease include:
- Vagotomy and pyloroplasty
- Vagotomy and antrectomy with gastroduodenal reconstruction (Billroth I)
- Gastrojejunal reconstruction (Billroth II)
- Highly selective vagotomy
Bleeding Gastric Ulcers
Bleeding gastric ulcers are treated according to the location of the ulcer. They are generally best treated by excision of the ulcer and repair of the resulting gastric defect. Excision or biopsy of the ulcer is mandatory, as 4–5% of benign-appearing ulcers are actually malignant.[3] The surgical approach is determined by ulcer location as follows:
| Ulcer Location | Preferred Surgical Approach |
|---|---|
| Greater curvature, antrum, or body of the stomach (non-lesser-curve) | Wedge excision of the ulcer with primary closure of the defect |
| Lesser curvature at the incisura angularis (Johnson Type II/III) | Distal gastrectomy with Billroth I (gastroduodenostomy) or Billroth II (gastrojejunostomy) reconstruction |
| Proximal gastric ulcer near the gastroesophageal junction (Johnson Type IV; <2 cm from cardia) | Csendes procedure: distal gastrectomy with tongue-shaped extension of the lesser curve resection margin to include the ulcer, followed by Roux-en-Y esophagogastrojejunostomy[3] |
| High lesser curve ulcer located 2–5 cm from the gastroesophageal junction | Partial gastrectomy with gastrojejunostomy (Pauchet's or Schoemaker's procedure); Roux-en-Y reconstruction preferred |
- For all excised gastric ulcer specimens, histopathological examination is mandatory to exclude malignancy.
- When wedge excision of a lesser-curve ulcer risks compromise of the gastroesophageal junction, an anterior gastrotomy with biopsy and intraluminal oversewing of the ulcer provides a safer alternative; the Csendes procedure is reserved for cases where excision is necessary.
Bleeding Duodenal Ulcers
The standard operative approach to a bleeding duodenal ulcer is:
- Perform an anterior longitudinal duodenotomy extending across the pylorus to the distal stomach
- Achieve hemostasis by direct suture ligation of the bleeding vessel (typically the gastroduodenal artery or its branches); the U-stitch technique ligating the gastroduodenal artery proximally, distally, and medially (three-point ligation) is the recommended technique
- Classically, truncal vagotomy was performed concomitantly to reduce the risk of recurrent ulceration; however, in the current era of effective proton pump inhibitor therapy and Helicobacter pylori eradication, routine vagotomy is increasingly omitted given the declining surgical expertise and the efficacy of postoperative medical therapy[4]
- Transarterial embolization (TAE) should be considered as the first-line salvage therapy for recurrent bleeding after duodenotomy and ulcer oversewing, before re-operative surgery is attempted[5][6]
A landmark randomized controlled trial by Ng et al. demonstrated that Helicobacter pylori eradication after simple closure of perforated duodenal ulcer significantly reduced ulcer recurrence, confirming the essential role of post-operative eradication therapy.[7] A meta-analysis and subsequent studies further confirmed that recurrent duodenal ulcer following perforation repair is strongly associated with ongoing H. pylori infection, underscoring the importance of universal testing and eradication.[7]
For large or giant perforated duodenal ulcers (>2 cm), the leak rate with simple omental patch repair increases significantly. Repair options in such cases include controlled tube duodenostomy, jejunal pedicled graft, pedicled omental plug technique, or partial gastrectomy, individualized to the patient's condition and surgeon's expertise.[1]
Perforated Peptic Ulcer
Perforated peptic ulcer (PPU) is a surgical emergency.[1] Prompt resuscitation and timely operative intervention are essential; every hour of delay in source control is associated with a 6% increased risk of death per hour.[8]
Nonoperative Management
Nonoperative management (NOM) of PPU may be considered in a highly selected subset of patients. Prerequisites for NOM per 2020 WSES guidelines include: haemodynamically stable vital signs, absence of peritoneal signs or sepsis, and confirmation of no contrast extravasation on a water-soluble contrast study (computed tomography with oral contrast or upper GI series).[1] The presence of free contrast extravasation, peritonitis, or haemodynamic instability mandates operative intervention.
Surgical Approach: Laparoscopic vs. Open
Immediate laparoscopic closure of perforated peptic ulcer is the treatment of choice in haemodynamically stable patients, provided appropriate skills and equipment are available.[1] Open repair is recommended when laparoscopic skills or equipment are unavailable, or in haemodynamically unstable patients.
A 2024 systematic review and meta-analysis of nine randomized controlled trials (670 patients: 317 laparoscopic, 353 open) confirmed that laparoscopic repair of PPU significantly reduces:[9]
| Outcome | Risk Ratio (RR) or Mean Difference (MD) | p-value |
|---|---|---|
| Mortality | RR 0.37 | p = 0.03 |
| Total complications | RR 0.57 | p = 0.0009 |
| Ileus | RR 0.43 | p = 0.04 |
| Wound complications | RR 0.36 | p < 0.0001 |
| Length of hospital stay | MD −2.37 days | p = 0.0003 |
No significant differences between laparoscopic and open surgery were found for suture leak, intra-abdominal abscess, or reoperation rate.[9]
Repair Techniques for Perforated Peptic Ulcer
| Technique | Description | Indications / Notes |
|---|---|---|
| Graham omental patch (modified Cellan-Jones repair) | Perforation closed with sutures; viable omentum tacked over the closure as a biological seal | Standard technique for most PPUs; laparoscopic omental patch repair (LOPR) demonstrated lower mortality and overall morbidity vs. open approach in meta-analysis of 29 studies (5,311 patients)[10] |
| Simple suture (primary) repair without omental patch | Direct closure of the perforation with interrupted sutures | Appropriate for small (<10 mm) perforations with viable edges; available evidence does not demonstrate a significant advantage of omental patching over simple closure alone in terms of leak rate or surgical outcomes[1] |
| Pedicled omental plug | A tongue of omentum is passed through the perforation and sutured to its edges from inside | Useful for giant perforations where suture closure is not feasible |
| Partial gastrectomy ± vagotomy | Distal gastrectomy with Billroth I, Billroth II, or Roux-en-Y reconstruction | Reserved for: large or giant perforations (>2 cm) with failed primary repair; perforated gastric ulcer with suspected malignancy; significant surrounding tissue necrosis; or ulcers not amenable to patch repair[2]. Outcomes of omental patch repair in large or giant PPU are comparable to gastrectomy when technically feasible[11] |
- All perforated gastric ulcer specimens must be sent for histopathology to exclude malignancy.
- Thorough peritoneal lavage with warm saline is recommended at the time of repair.
- Intraoperative peritoneal cultures should be obtained to guide antimicrobial therapy.
- Routine abdominal drainage is not mandatory but may be placed at the surgeon's discretion.
- H. pylori testing should be performed intraoperatively (antral biopsy passed through the perforation site) or in the early postoperative period; eradication therapy is indicated in all positive patients.[7]
Medical Therapy
Concurrent and postoperative medical therapy is critical for ulcer healing and prevention of recurrence.
Helicobacter pylori Eradication
Helicobacter pylori eradication is the cornerstone of long-term ulcer management. The 2024 ACG Clinical Guideline recommends the following first-line strategies in treatment-naïve patients when antibiotic susceptibility is unknown:[12]
- Optimized bismuth quadruple therapy (BQT) for 14 days as the preferred first-line empiric regimen
- Rifabutin triple therapy or vonoprazan-based dual therapy with amoxicillin for 14 days as suitable alternatives
- Clarithromycin- and levofloxacin-containing regimens should be avoided empirically in the absence of confirmed antibiotic susceptibility
Post-treatment test-of-cure with a urea breath test or stool antigen test is recommended for all treated patients. NSAIDs should be discontinued or used at the lowest effective dose with concurrent PPI co-prescription.
Acid Suppression
After endoscopic or surgical hemostasis for bleeding peptic ulcer, high-dose intravenous PPI therapy (continuous infusion) for the first 72 hours reduces rebleeding, the need for further intervention, and mortality. PPI therapy for 6–8 weeks is recommended following endoscopic or surgical treatment. Long-term PPI therapy is not routinely recommended unless patients have ongoing NSAID requirements.[1]
Gastric Outlet Obstruction
Gastric outlet obstruction resulting from chronic PUD usually reflects pyloric or proximal duodenal scarring. Endoscopic balloon dilation is the primary non-surgical therapy but is limited by a high risk of perforation and poor long-term durability due to ongoing ulcer activity. Surgical management is the preferred approach when endoscopic measures fail.[2]
Surgical options include:
- Gastrojejunostomy (loop or Roux-en-Y): preferred in extensive duodenal scarring; provides durable gastric drainage
- Pyloroplasty or duodenoplasty: suitable where limited pyloric scarring permits adequate reconstruction
- Antrectomy with Billroth I or Billroth II reconstruction: provides both drainage and acid reduction, with or without vagotomy
- Truncal vagotomy combined with a drainage procedure: historically effective for benign obstruction; less frequently performed in the modern era owing to declining expertise and the availability of effective acid suppression
Elective Surgery for Refractory or Recurrent Peptic Ulcer
Elective surgery is now uncommon but remains indicated for medically refractory disease, large or giant ulcers failing to heal with optimal medical management, suspected occult malignancy, and Zollinger-Ellison syndrome refractory to medical management.[2]
Elective surgical procedures include:
- Highly selective vagotomy (proximal gastric vagotomy): Denervates the acid-secreting parietal cell mass while preserving antral innervation and gastric emptying, thus avoiding the need for a drainage procedure. Associated with lower rates of dumping syndrome compared with truncal vagotomy and pyloroplasty. Ulcer recurrence rates are higher (approximately 10–15%) than with procedures incorporating antrectomy. Surgical expertise in this procedure has declined markedly.
- Truncal vagotomy and pyloroplasty: Bilateral sectioning of vagal trunks at the esophageal hiatus plus a drainage procedure (Heineke-Mikulicz, Finney, or Jaboulay pyloroplasty). Effective acid reduction with acceptable morbidity.
- Truncal vagotomy and antrectomy: Provides the lowest ulcer recurrence rates (~1%) but carries the greatest risk of postgastrectomy complications including dumping syndrome and nutritional deficiencies.
- Distal (subtotal) gastrectomy: Preferred for gastric ulcers with concern for malignancy. Billroth I reconstruction is preferred when technically feasible; Billroth II or Roux-en-Y gastrojejunostomy is used when a tension-free anastomosis to the duodenum cannot be achieved.
Postoperative Care and Long-Term Management
Following surgical intervention for PUD, long-term management should address the following:
- Helicobacter pylori testing and eradication: All patients with PUD who have not been previously tested should undergo H. pylori testing; those who test positive require eradication therapy with confirmed test-of-cure.[12]
- PPI therapy: Long-term PPI is indicated in patients requiring ongoing NSAID therapy; it is not routinely required after confirmed H. pylori eradication in NSAID-naive patients.[1]
- NSAID avoidance: Patients requiring ongoing analgesics should be transitioned to acetaminophen where possible, or to the lowest effective dose of a selective COX-2 inhibitor plus a PPI.
- Smoking cessation: Cigarette smoking impairs ulcer healing and is an independent risk factor for recurrence; cessation is strongly recommended.
- Surveillance endoscopy: Repeat upper endoscopy is mandated for gastric ulcers to confirm healing and exclude malignancy, typically at 6–8 weeks after initiation of therapy.
- Nutritional supplementation: Patients who have undergone partial or total gastrectomy require monitoring and supplementation of vitamin B12, iron, folate, calcium, and vitamin D.
Postgastrectomy Syndromes
Patients undergoing gastric resection or drainage procedures are at risk of well-characterized postgastrectomy syndromes:
| Syndrome | Mechanism | Clinical Features | Management |
|---|---|---|---|
| Dumping syndrome (early) | Rapid gastric emptying → hyperosmolar load in small bowel → fluid shifts and autonomic activation within 15–30 min of eating | Nausea, abdominal cramps, diarrhea, palpitations, flushing | Small frequent meals; avoid simple carbohydrates and liquids with meals; octreotide for refractory cases |
| Dumping syndrome (late) | Reactive hypoglycemia 2–3 hours postprandially from hyperinsulinemia following rapid carbohydrate absorption | Diaphoresis, dizziness, weakness, hypoglycemia | Dietary modification; acarbose; somatostatin analogues for refractory cases |
| Afferent loop syndrome | Obstruction of the afferent jejunal limb after Billroth II reconstruction → biliopancreatic secretion stasis | Postprandial bilious vomiting, abdominal distension; acute form may cause sepsis | Endoscopic balloon dilation for benign strictures; Roux-en-Y surgical conversion for mechanical obstruction; endoscopic ultrasound-guided lumen-apposing metal stent (LAMS) for poor surgical candidates |
| Alkaline reflux gastritis | Reflux of bile and pancreatic secretions into gastric remnant after Billroth II or drainage procedures | Epigastric burning, bilious vomiting, weight loss | Ursodeoxycholic acid; dietary measures; Roux-en-Y conversion for severe or refractory cases |
| Marginal (anastomotic) ulcer | Acid at gastrojejunal or gastroduodenal anastomosis after gastric surgery | Epigastric pain, upper gastrointestinal bleeding | PPI therapy; exclude incomplete vagotomy, retained antrum syndrome, ongoing H. pylori infection; surgical revision if medically refractory |
| Nutritional deficiencies | Reduced intrinsic factor, gastric acid, and absorptive surface | B12 deficiency, iron deficiency anemia, metabolic bone disease | Periodic blood tests; parenteral B12; oral iron; calcium and vitamin D supplementation |
| Postvagotomy diarrhea | Accelerated intestinal transit; altered bile acid metabolism following vagotomy | Watery diarrhea, urgency | Dietary modification; cholestyramine; anti-motility agents |
Special Populations
Elderly Patients
Older patients (>70 years) presenting with PPU have significantly higher morbidity and mortality. Surgery should not be delayed even in elderly patients with peritonitis, as delay beyond 24 hours is strongly associated with increased mortality.[8] Laparoscopic approaches, when feasible within the patient's physiologic reserve, are preferred to reduce wound complications and shorten hospital stay. Enhanced recovery after surgery (ERAS) protocols should be applied when operative timing permits.
Patients on Anticoagulation or Antiplatelet Therapy
Patients on anticoagulant or antiplatelet therapy presenting with bleeding peptic ulcer represent a high-risk group. Reversal of anticoagulation should be performed in consultation with cardiology and haematology when safe. Endoscopy remains first-line therapy; surgery is reserved for failure of endoscopic and angiographic control. The indication for ongoing antithrombotic therapy should be reassessed post-operatively and therapy reinstituted at the earliest safe opportunity.
Patients with NSAID-Induced Ulcers
NSAIDs should be discontinued whenever possible. In patients requiring ongoing NSAID therapy (e.g., for rheumatoid arthritis or cardiovascular prophylaxis), a selective COX-2 inhibitor at the lowest effective dose combined with a PPI reduces but does not eliminate ulcer risk. Surgical intervention for NSAID-induced complications follows the same principles as for H. pylori-associated ulcers.
Patients with Zollinger-Ellison Syndrome
Patients with Zollinger-Ellison syndrome require preoperative localization of gastrinoma (via computed tomography, magnetic resonance imaging, or somatostatin receptor scintigraphy) and biochemical assessment. High-dose PPI or vonoprazan controls acid hypersecretion in the majority of patients. Surgical exploration with curative intent is appropriate for sporadic, resectable gastrinomas. In patients with multiple endocrine neoplasia type 1 (MEN-1), surgical cure is rarely achieved and medical management of the acid hypersecretory state is preferred.
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 Tarasconi A, Coccolini F, Biffl WL, Tomasoni M, Ansaloni L, Picetti E, Molfino S, Shelat V, Cimbanassi S, Weber DG, Abu-Zidan FM, Campanile FC, Di Saverio S, Baiocchi GL, Casella C, Kelly MD, Kirkpatrick AW, Leppaniemi A, Moore EE, Peitzman A, Pereira Fraga G, Ceresoli M, Maier RV, Wani I, Pattonieri V, Perrone G, Velmahos G, Sugrue M, Sartelli M, Kluger Y, Catena F (2020). "Perforated and bleeding peptic ulcer: WSES guidelines". World J Emerg Surg. 15 (1): 3. doi:10.1186/s13017-019-0283-9. PMID 31903027.
- ↑ 2.0 2.1 2.2 2.3 Masoudpour H, Wassef J, Saladziute S, Sherman J (2025 Feb). "Surgical Therapy of Gastric Ulcer Disease". Surg Clin North Am. 105 (1): 173–186. doi:10.1016/j.suc.2024.06.013. PMID 39523072 Check
|pmid=value (help). Check date values in:|date=(help) - ↑ 3.0 3.1 Csendes A, Braghetto I, Calvo F, De la Cuadra R, Velasco N, Schutte H, Sepulveda A, Lazo M (1985). "Surgical treatment of high gastric ulcer". Am J Surg. 149 (6): 765–70. PMID 4014553.
- ↑ Gilliam AD, Speake WJ, Lobo DN, Beckingham IJ (2003). "Current practice of emergency vagotomy and Helicobacter pylori eradication for complicated peptic ulcer in the United Kingdom". Br J Surg. 90 (1): 88–90. doi:10.1002/bjs.4003. PMID 12520581.
- ↑ Eriksson LG, Ljungdahl M, Sundbom M, Nyman R (2008). "Transcatheter arterial embolization versus surgery in the treatment of upper gastrointestinal bleeding after therapeutic endoscopy failure". J Vasc Interv Radiol. 19 (10): 1413–8. doi:10.1016/j.jvir.2008.06.019. PMID 18755604.
- ↑ Holme JB, Nielsen DT, Funch-Jensen P, Mortensen FV (2006). "Transcatheter arterial embolization in patients with bleeding duodenal ulcer: an alternative to surgery". Acta Radiol. 47 (3): 244–7. PMID 16613304.
- ↑ 7.0 7.1 7.2 Ng EK, Lam YH, Sung JJ, Yung MY, To KF, Chan AC, Lee DW, Law BK, Lau JY, Ling TK, Lau WY, Chung SC (2000). "Eradication of Helicobacter pylori prevents recurrence of ulcer after simple closure of duodenal ulcer perforation: randomized controlled trial". Ann Surg. 231 (2): 153–8. doi:10.1097/00000658-200002000-00001. PMC 1420980. PMID 10674604.
- ↑ 8.0 8.1 Boyd-Carson H, Doleman B, Herrod P, Anderson I, Lund JN, Williams JP, National Emergency Laparotomy Audit C (2020 Mar). "Delay in Source Control in Perforated Peptic Ulcer Leads to 6% Increased Risk of Death Per Hour: A Nationwide Cohort Study". World J Surg. 44 (3): 869–875. doi:10.1007/s00268-019-05230-1. PMID 31574174. Vancouver style error: initials (help); Check date values in:
|date=(help) - ↑ 9.0 9.1 Sokhal BS, Mohamedahmed A, Zaman S, Wuheb AA, Abdalla HE, Husain N, Hajibandeh S, Hajibandeh S (2024 Oct 3). "Laparoscopic versus open repair for peptic ulcer perforation: a systematic review, meta-analysis and trial sequential analysis of randomised controlled trials". Ann R Coll Surg Engl. doi:10.1308/rcsann.2024.0082. PMID 39363728 Check
|pmid=value (help). Vancouver style error: initials (help); Check date values in:|date=(help) - ↑ Chan KS, Wang YL, Chan XW, Shelat VG (2023 Jan). "A systematic review and meta-analysis comparing postoperative outcomes of laparoscopic versus open omental patch repair of perforated peptic ulcer". J Trauma Acute Care Surg. 94 (1): e1–e13. doi:10.1097/TA.0000000000003799. PMID 36218093 Check
|pmid=value (help). Check date values in:|date=(help) - ↑ Chan KS, Wang YL, Chan XW, Shelat VG (2021 Dec). "Outcomes of omental patch repair in large or giant perforated peptic ulcer are comparable to gastrectomy". Eur J Trauma Emerg Surg. 47 (6): 1745–1752. doi:10.1007/s00423-020-01933-9. PMID 33834286 Check
|pmid=value (help). Check date values in:|date=(help) - ↑ 12.0 12.1 Chey WD, Howden CW, Moss SF, Morgan DR, Greer KB, Grover S, Shah SC (2024 Sep 1). "ACG Clinical Guideline: Treatment of Helicobacter pylori Infection". Am J Gastroenterol. 119 (9): 1730–1753. doi:10.14309/ajg.0000000000002968. PMID 39159922 Check
|pmid=value (help). Check date values in:|date=(help)