What is the management of a severely elevated right hemidiaphragm?

Management of Severely Elevated Right Hemidiaphragm

Surgery with diaphragmatic plication is indicated for all symptomatic patients with a severely elevated right hemidiaphragm, preferably via a minimally invasive thoracoscopic approach. 1

Initial Diagnostic Workup

First-Line Imaging

• Obtain chest X-ray (PA and lateral views) as the initial diagnostic study to confirm hemidiaphragm elevation 2
• Look specifically for abnormal lucency, soft tissue opacity with mediastinal deviation, or clear hemidiaphragm elevation 2
• Evaluate the shape of the elevated diaphragm on lateral chest radiograph: a radius of curvature with HH/APD > 0.28 suggests eventration rather than paralysis 3

Advanced Imaging

• CT scan of chest and abdomen with contrast is the gold standard for diagnosis (sensitivity 14-82%, specificity 87%) 2
• Critical CT findings to identify include:
  • Diaphragmatic discontinuity or the "collar sign" (constriction of herniating organ) 2
  • "Dependent viscera" sign (abdominal organs abutting chest wall) 2
  • Thickened or elevated diaphragm 2
  • Herniated abdominal contents (liver, bowel, stomach) 4

Functional Assessment

• Fluoroscopic sniff test differentiates the etiology: paradoxical motion indicates paralysis, while no paradoxical motion suggests eventration 1, 3
• This distinction is important but does not change surgical management in symptomatic patients 1

Critical Differential Diagnosis

Diaphragmatic Hernia (Traumatic or Non-Traumatic)

• Right-sided diaphragmatic hernias are less common clinically (12-40% of blunt trauma cases) but more common in autopsy series (49.6%), suggesting higher mortality 4
• Undetected diaphragmatic hernia can cause bowel strangulation, perforation, peritonitis, and multi-organ failure - a surgical emergency with high mortality 4
• Delayed diagnosis occurs in 5-45% of cases, with right-sided ruptures accounting for 50% of delayed diagnoses 4

Eventration vs. Paralysis

• Both present with elevated hemidiaphragm but differ in diaphragmatic motion 1
• Eventration: abnormal elevation due to aplasia of muscular fibers, no paradoxical motion 5
• Paralysis: phrenic nerve dysfunction causing paradoxical upward motion during inspiration 1, 6

Other Causes

• Subdiaphragmatic pathology (abscess, tumor, hepatomegaly) pushing diaphragm upward 2
• Endometriosis-related diaphragmatic fenestration in women with history of catamenial pneumothorax 7

Surgical Management

Indications for Surgery

Operate on all symptomatic patients regardless of etiology (eventration, paralysis, or hernia). 1, 5 Symptoms warranting surgery include:

• Dyspnea or tachypnea 4, 5
• Recurrent pneumonia 5
• Failure to thrive (in children) 5
• Persistent chest pain 7
• Inability to wean from mechanical ventilation 6

Surgical Approach for Diaphragmatic Hernia

• In stable patients: laparoscopic approach is strongly recommended (Class 1B evidence) 4, 2
• In unstable patients: perform laparotomy (Class 2C evidence) 4, 2
• Primary repair with non-absorbable 2-0 or 1-0 sutures in two layers using interrupted mattress technique should always be attempted 4

Surgical Approach for Eventration/Paralysis

• Minimally invasive thoracoscopic plication is the preferred approach for most thoracic surgeons 1
• Alternative approaches include open thoracotomy or abdominal approach 1
• The goal is to restore normal diaphragm position, improve lung volumes, and eliminate paradoxical motion 1, 5

Management of Large Defects

• For defects >3 cm, use mesh reinforcement to prevent the 42% recurrence rate seen with primary repair alone 4, 2
• Biosynthetic, biologic, or composite meshes are preferred over synthetic due to lower recurrence rates, higher infection resistance, and lower displacement risk (Class 2C evidence) 4, 2
• Suture the defect first to provide a flat surface for mesh placement 4

Special Surgical Considerations

• In women with history of catamenial pneumothorax and elevated right hemidiaphragm, suspect massive diaphragmatic fenestration with liver herniation - may require combined thoracotomy and laparotomy 7
• Hernial sac excision is controversial; retention generally causes no complications, but excision may reduce recurrence when stomach or colon is involved 4

Expected Outcomes

Post-Plication Results

• Immediate symptom remission occurs in most patients 5
• The plicated hemidiaphragm becomes immobile without paradoxical motion 5
• Normal diaphragm position is restored in >90% of cases 5
• Significant improvement in transdiaphragmatic pressure, work of breathing, and ability to wean from ventilator 6
• Diaphragm plication is safe with excellent outcomes and durable symptom improvement 1

Critical Pitfalls to Avoid

• Never dismiss a "persistently elevated right hemidiaphragm" as simple phrenic nerve palsy without ruling out diaphragmatic hernia or fenestration, especially in patients with persistent chest pain 7
• Do not miss bilateral hernias - they occur in 1-9% of blunt trauma cases and require grading one level higher on the AAST scale 8
• Avoid delaying surgery in symptomatic patients - undetected hernias can lead to catastrophic complications including bowel strangulation and multi-organ failure 4
• Be aware that normal chest radiographs occur in 11-62% of diaphragmatic injuries - maintain high clinical suspicion and proceed to CT if symptoms persist 2
• In trauma patients with lower chest penetrating wounds and nonspecific findings, perform diagnostic laparoscopy to avoid missed diaphragmatic injuries 8