When should I suspect and evaluate a hiatal hernia in a patient with gastro‑oesophageal reflux or obstruction symptoms, and what diagnostic tests should be performed?

When to Suspect and Evaluate Hiatal Hernia

Order a biphasic esophagram (barium swallow with double-contrast) as the initial imaging test when patients present with typical GERD symptoms (heartburn, regurgitation) that fail a 4–8 week trial of PPI therapy, or immediately when alarm symptoms are present. 1, 2

Clinical Scenarios Requiring Hiatal Hernia Evaluation

Immediate Evaluation (No PPI Trial)

• Alarm symptoms: dysphagia, odynophagia, unexplained weight loss, anemia, or gastrointestinal bleeding mandate immediate objective testing with both upper endoscopy and biphasic esophagram rather than empirical therapy 3
• Severe epigastric pain: may indicate gastric volvulus or ischemia requiring urgent contrast-enhanced CT of chest/abdomen to exclude complications 4
• Regurgitation-predominant GERD: these patients often have significant anatomic disruption of the anti-reflux barrier and benefit from early imaging 1

After Failed Medical Management

• PPI non-response: patients with persistent symptoms after 4–8 weeks of single-dose PPI (or escalation to twice-daily dosing) should undergo objective testing 1
• Long-term PPI therapy planned: objective reflux testing should be offered to establish diagnosis and guide long-term management 1
• Central obesity or known hiatal hernia: suggests mechanical contribution to reflux, prompting earlier imaging evaluation 3

Pre-Surgical Evaluation

• All patients considered for anti-reflux surgery must undergo barium esophagram per the American College of Surgeons Esophageal Diagnostic Advisory Panel consensus 1, 3, 4
• Refractory GERD despite optimized medical therapy: requires comprehensive evaluation including imaging before surgical referral 4

Diagnostic Testing Algorithm

Step 1: Initial Imaging – Biphasic Esophagram

The biphasic esophagram is the first-line imaging study, combining double-contrast views (optimizing detection of inflammatory conditions) with single-contrast views (optimizing detection of hiatal hernias and strictures), achieving 88% sensitivity 2

This study provides:

• Detection and sizing of hiatal hernia 1, 2
• Anatomic information on esophageal length (critical for identifying "short esophagus" requiring lengthening procedures) 1, 4
• Functional assessment of gastroesophageal reflux 1
• Identification of strictures, rings, or other structural abnormalities 1, 2
• Differentiation between sliding hernias (Type I, 90% of cases) and paraesophageal hernias (Type II-IV), which require different surgical approaches 2, 4

Common pitfall: Single-contrast esophagram alone has only 77% sensitivity and may miss mucosal irregularities from reflux disease 1, 2

Step 2: Upper Endoscopy

Perform upper GI endoscopy to:

• Detect erosive esophagitis, Barrett's esophagus, or strictures 1
• Assess for associated conditions including eosinophilic esophagitis 1
• Rule out malignancy in patients with alarm symptoms 1
• Obtain biopsies when Barrett's esophagus is suspected 4

Important caveat: Endoscopy has poor sensitivity (66%) for detecting hiatal hernia itself and should not be relied upon as the primary diagnostic modality for hernia detection 5

Step 3: Advanced Testing When Indicated

Contrast-Enhanced CT (Chest and Abdomen)

Reserve CT for complicated cases or when clinical suspicion remains high despite inconclusive initial studies 3, 2, 4

Indications for CT include:

• Persistent high clinical suspicion despite inconclusive chest radiograph or esophagram 3
• Evaluation for complications: ischemia (absent gastric wall enhancement, intestinal wall thickening), strangulation, volvulus, or incarceration 3, 4
• Trauma patients with suspected diaphragmatic injury 3
• Post-bariatric surgery patients where internal hernia is suspected 3

CT is the gold standard for complicated diaphragmatic/hiatal hernias with 14–82% sensitivity and 87% specificity, superior for determining presence, location, and size of diaphragmatic defects 3, 2

Critical warning: Normal chest X-rays occur in 11–62% of diaphragmatic hernias, making plain radiography unreliable for excluding hernia 3, 2, 4

High-Resolution Manometry

Mandatory before any anti-reflux or hiatal hernia surgery to:

• Assess esophageal peristaltic function 1, 4
• Exclude achalasia 1, 4
• Evaluate peristaltic reserve when partial fundoplication is being considered 1

Note: High-resolution manometry can detect subtle hiatal hernias <2 cm that are missed by endoscopy or radiography, but has poor sensitivity (48%) and is not recommended as a primary diagnostic tool for hernia detection 6, 5

24-Hour pH-Impedance Monitoring

Consider ambulatory pH-impedance monitoring on PPI when:

• Symptoms persist despite therapy and you need to confirm PPI-refractory GERD 1
• Excluding overlap with reflux hypersensitivity, rumination syndrome, or belching disorders 1
• Objective documentation of acid exposure is needed before surgical intervention 4

In patients with negative endoscopy, prolonged wireless pH monitoring off PPI therapy assesses esophageal acid exposure 1

Step 4: Pre-Operative Work-Up (Complete Evaluation)

Before proceeding to surgery, complete the following:

1. Barium esophagram (already performed) 1, 3, 4
2. Upper endoscopy with biopsy to confirm Barrett's esophagus (if present), evaluate dysplasia, and assess esophagitis severity 4
3. High-resolution manometry to evaluate peristaltic function and rule out achalasia 1, 4
4. 24-hour pH-impedance monitoring to confirm refractory GERD and document acid exposure patterns 4

Critical pitfall: Never assume Barrett's status is unchanged after several years—23.9% of esophageal adenocarcinomas in Barrett's patients are diagnosed within 1 year of a "negative" endoscopy 4

Special Populations

Pregnant Patients

Use ultrasonography as the first imaging modality for suspected non-traumatic diaphragmatic hernia to avoid ionizing radiation, reserving MRI for further assessment if ultrasonography is inconclusive 3, 2

Trauma Patients

For hemodynamically stable patients with lower-chest penetrating wounds, diagnostic laparoscopy is preferred over imaging for definitive evaluation of diaphragmatic integrity 3, 2

Key Clinical Pearls

• Hiatal hernia is strongly associated with GERD pathophysiology: it reduces LES length and pressure, impairs diaphragmatic crural augmentation, and acts as a reservoir allowing reflux 7, 8
• Presence of hiatal hernia correlates with increased severity of reflux esophagitis, Barrett's esophagus, and reduced PPI efficacy 7
• 60% of patients with erosive esophagitis have hiatal hernia, and 49% of patients with hiatal hernia have erosive esophagitis 8
• External compression devices (hernia belts) have no role in treating hiatal hernias because the stomach herniates through the esophageal hiatus into the thoracic cavity, making external pressure mechanically irrelevant 4