Effective pain management in patients with multiple rib fractures is a cornerstone of trauma care.

Inadequate analgesia can impair ventilation, suppress cough, and increase the risk of pulmonary complications such as atelectasis, pneumonia, and acute respiratory distress syndrome (ARDS).

A new randomized controlled noninferiority trial published in the British Journal of Anaesthesia (2026) directly compared:

• Continuous posterior extrathoracic fascial plane block (PEFB)
  
• Continuous paravertebral block (PVB)
  
• Systemic multimodal analgesia alone
  

The findings offer important clinical insights for anesthesiologists, intensivists, and trauma teams.

Study overview

According to the randomized controlled trial by Ramin et al., the objective was to determine whether continuous PEFB is noninferior to PVB in reducing opioid consumption in trauma patients with multiple rib fractures.

Study design

• Prospective, randomized, controlled, noninferiority trial
  
• Conducted in a Level I trauma ICU in France
  
• 90 trauma patients enrolled
  
• Three parallel groups (1:1:1 randomization)
  

Inclusion criteria

• ≥ 2 homolateral rib fractures
  
• Numeric rating scale (NRS) pain score ≥ 3 during coughing or mobilization
  
• Admission within 24 hours of trauma
  
• Not mechanically ventilated
  

Primary endpoint

• Cumulative morphine consumption at 24 hours
  

Secondary endpoints

• Total morphine consumption at 72 hours
  
• Pain scores at rest and during coughing
  
• Rescue thoracic epidural analgesia (TEA)
  
• Respiratory parameters:
  
  • Sniff nasal inspiratory pressure (SNIP)
    
  • Maximal expiratory pressure (MEP)
    
• Complications
  

Understanding the analgesic techniques

Posterior extrathoracic fascial plane block (PEFB)

PEFB is a thoracic interfascial plane block targeting the posterior extrathoracic fascia.

It aims to block:

• Dorsal rami of thoracic spinal nerves
  
• Lateral and potentially ventral branches via fascial spread
  

Mechanism:

• Local anesthetic spreads between:
  
  • Serratus anterior muscle
    
  • Rhomboid muscle
    
  • Posterior thoracic fascia
    
• May reach multiple intercostal spaces
  

Advantages:

• Technically simpler
  
• Ultrasound-guided
  
• Lower theoretical risk compared to neuraxial techniques
  

Limitations:

• Spread may be variable
  
• Anterior chest wall coverage may be incomplete

Paravertebral block (PVB)

PVB involves injection of local anesthetic into the thoracic paravertebral space.

This produces:

• Unilateral somatic and sympathetic blockade
  
• Reliable intercostal nerve anesthesia
  

Advantages:

• Established efficacy
  
• Sustained analgesia
  
• Better anterior chest wall coverage
  

Limitations:

• Technical difficulty
  
• Risk of vascular puncture
  
• Potential pneumothorax
  
• Contraindicated in coagulopathy
  

Primary outcome: morphine consumption at 24 hours

Median morphine use:

• PEFB: 17 mg
  
• PVB: 21.5 mg
  

The difference was −3 mg (95% CI within noninferiority margin).

Key conclusion

PEFB was noninferior to PVB for morphine consumption at 24 hours.

This suggests that PEFB provides comparable short-term opioid-sparing effects.

Secondary outcomes

1. Morphine consumption at 72 hours

Median cumulative morphine:

• Control: 45 mg
  
• PEFB: 30 mg
  
• PVB: 38.5 mg
  

No statistically significant difference (P=0.051).

2. Rescue thoracic epidural analgesia (TEA)

This was a crucial finding.

Rescue TEA required:

• Control group: 30%
  
• PEFB group: 30%
  
• PVB group: 6.7%
  

Significant difference (P=0.043).

Interpretation

PVB demonstrated:

• Greater durability
  
• Lower failure rate
  
• Reduced need for escalation to epidural
  

PEFB may provide adequate early analgesia but may wane after 24 hours.

3. Pain scores

• No significant difference in pain at rest
  
• Pain during coughing was significantly lower in the PVB group
  
• Pain decreased over time in all groups

4. Respiratory function

Sniff nasal inspiratory pressure (SNIP)

• Improved in all groups
  
• No significant difference between groups
  

Maximal expiratory pressure (MEP)

• Significantly higher in PVB group
  
• Suggests improved expiratory muscle function
  

Improved MEP may enhance:

• Cough effectiveness
  
• Secretion clearance
  
• Prevention of pneumonia
  

Safety outcomes

Complications were rare.

• One vascular puncture in PVB group
  
• No catheter infections
  
• No seizures
  
• No arrhythmias
  

Interestingly:

• ARDS occurred in 13.3% of PVB patients
  
• None in control or PEFB groups
  

This finding warrants cautious interpretation.

Clinical implications

When to consider PEFB

PEFB may be ideal for:

• Patients with contraindications to neuraxial techniques
  
• Coagulopathy
  
• Hemodynamic instability
  
• When simpler technique preferred
  

When to favor PVB

PVB may be superior for:

• Sustained analgesia
  
• Severe anterior rib fractures
  
• Patients at high risk for pulmonary complications
  
• Need for improved cough mechanics

Key takeaways

• PEFB is noninferior to PVB for 24-hour opioid consumption.
  
• PVB reduces need for rescue epidural analgesia.
  
• PVB improves expiratory muscle strength.
  
• PEFB remains a practical alternative in selected patients.

Final thoughts

This randomized controlled trial provides high-quality evidence that continuous posterior extrathoracic fascial plane block is a viable first-line alternative to paravertebral block in trauma patients with multiple rib fractures.

However, paravertebral block appears more durable and more effective for dynamic pain and expiratory function.

For trauma anesthesiologists and intensivists, these findings refine our approach to multimodal rib fracture analgesia and highlight the importance of individualized regional anesthesia strategies.

As chest trauma remains a major cause of morbidity worldwide, optimizing regional analgesia continues to be essential for improving respiratory outcomes and reducing opioid exposure.

Reference: Ramin S et al. Continuous posterior extrathoracic fascial plane block versus continuous paravertebral block for pain management in patients with multiple rib fractures: a randomised controlled noninferiority trial. Br J Anaesth. 2026;136:677-686.Learn more about this study in NYSORA’s Anesthesia Assistant App.