How to manage postoperative diaphragmatic eventration?

Management of Postoperative Diaphragmatic Eventration

Postoperative diaphragmatic eventration in symptomatic adults should be managed with surgical diaphragmatic plication via minimally invasive thoracoscopic approach, while asymptomatic patients can be observed conservatively with close monitoring of respiratory function.

Initial Assessment and Indications for Intervention

The decision to intervene surgically depends critically on symptom severity and respiratory compromise 1, 2:

• Symptomatic patients presenting with severe dyspnea (MRC grade ≥3), orthopnea, or respiratory distress requiring mechanical ventilation warrant urgent surgical intervention 3, 2, 4
• Asymptomatic or minimally symptomatic patients may be managed conservatively, though this remains controversial as some advocate for early repair to optimize lung function 1, 3
• Assess baseline pulmonary function with FEV1 and FVC measurements, as significant improvement post-plication is expected (mean FEV1 improvement from 63.5% to higher values) 2

Key clinical indicators for surgery include:

• Inability to wean from mechanical ventilation postoperatively 3
• Progressive respiratory distress unresponsive to medical therapy 1
• Significant compression of lung parenchyma by herniated abdominal contents 3

Perioperative Respiratory Management

Ventilatory Support Strategy

Optimize ventilation while minimizing lung injury 5:

• Monitor SpO2 continuously and assess blood or end-tidal CO2 levels whenever possible 5
• Use supplemental oxygen cautiously - assess whether hypoxemia stems from hypoventilation, atelectasis, or airway secretions and treat the underlying cause 5
• If mechanical ventilation is required, consider non-invasive positive pressure ventilation (NPPV) as a bridge to extubation rather than prolonged intubation 5
• Delay extubation until respiratory secretions are well-controlled and SpO2 is at baseline on room air 5

Airway Clearance and Secretion Management

Aggressive pulmonary toilet is essential 5:

• Implement manually assisted cough techniques and mechanical insufflation-exsufflation (MI-E) in patients with impaired cough (peak cough flow <270 L/min or maximal expiratory pressure <60 cm H2O) 5
• Provide multimodal physiotherapy combining early mobilization, breathing exercises, bronchial drainage, and coughing techniques 5
• Postoperative pulmonary complications including atelectasis are common and require proactive management 5

Surgical Approach

Technique Selection

Minimally invasive uniportal video-assisted thoracoscopic surgery (VATS) is the preferred approach for stable patients 6, 4:

• Uniportal VATS offers superior postoperative pain control and cosmesis with equivalent outcomes to open thoracotomy 6, 4
• The procedure involves either plication using reefing mattress sutures on pledgets or stapled resection of the redundant diaphragm 3, 6, 4
• Laparoscopic approach may be considered but thoracoscopic access provides better visualization and repair of the diaphragm 3, 6

Open thoracotomy is reserved for:

• Hemodynamically unstable patients 5
• Cases requiring extensive adhesiolysis or concurrent procedures 6
• Failed minimally invasive attempts 3

Technical Considerations

Ensure adequate plication tension 3:

• Use non-absorbable sutures for primary repair to prevent recurrence 5
• The plication must be tight enough to prevent recurrence - inadequate tension is a common cause of failure requiring reoperation 3
• For defects >8 cm or >20 cm², consider mesh reinforcement, though this is rarely needed in pure eventration 5

Postoperative Care

Immediate Postoperative Period

Expect rapid respiratory improvement after successful plication 3, 2:

• Ventilatory support can typically be discontinued within 0-6 days (mean 3 days) after surgery in patients with phrenic nerve injury 3
• Monitor for dramatic resolution of respiratory symptoms, which should occur promptly 3, 2
• Continue multimodal physiotherapy with early mobilization and breathing exercises 5

Pain Management

Optimize analgesia while avoiding respiratory depression 5:

• Use regional analgesia techniques (paravertebral block preferred over epidural for better safety profile) when feasible 5
• Short courses of NSAIDs are recommended postoperatively 5
• If opioids cause sedation or hypoventilation, use NPPV continuously or delay extubation for 24-48 hours 5

Gastrointestinal Management

Address GI dysfunction that can impair diaphragmatic excursion 5:

• Initiate bowel regimens preoperatively and continue postoperatively to prevent constipation 5
• Consider prokinetic medications for patients with gastroparesis or intestinal dysmotility 5
• Gastric decompression with nasogastric tube may be necessary if abdominal distention occurs 5
• If oral nutrition cannot be achieved within 24-48 hours, initiate enteral feeding via small-diameter tube or parenteral nutrition 5

Monitoring and Follow-up

Close postoperative surveillance is essential 5, 2:

• Monitor respiratory rate, heart rate, blood pressure, SpO2, and pain scores continuously in recovery 5
• Assess for warning signs including stridor, obstructed breathing pattern, or agitation 5
• Obtain follow-up pulmonary function tests at 6 months to document improvement in FEV1 and FVC 2
• Watch for recurrence, which may result from suture failure, inadequate initial plication, or increased intra-abdominal pressure 5

Common Pitfalls

Avoid these critical errors:

• Delaying surgery in symptomatic patients - respiratory distress can progress rapidly and prolonged ventilation increases morbidity 3, 2
• Inadequate plication tension - this is the most common technical error requiring reoperation 3
• Overzealous oxygen supplementation - this can mask hypoventilation; always assess CO2 levels 5
• Neglecting GI management - abdominal distention impairs diaphragmatic function and can compromise the repair 5
• Using absorbable sutures - these contribute to recurrence 5