Maximum Infusion Rate for Thoracic Epidural
The maximum infusion rate for a thoracic epidural is 10 ml per hour, with patient-controlled boluses of up to 5 ml with a lockout time of 40 minutes. 1
Evidence-Based Recommendations
The PROSPECT guidelines for video-assisted thoracoscopic surgery provide specific information about thoracic epidural infusion rates. According to these guidelines, thoracic epidural analgesia typically uses:
- Initial infusion rates of 5-10 ml/h
- Postoperative infusion rates of 5-10 ml/h
- Patient-controlled boluses of 5 ml with a 40-minute lockout interval 1
Medication Considerations
The thoracic epidural solution typically consists of:
- Local anesthetic (commonly ropivacaine 1.5-2.5 mg/ml or bupivacaine 1.25 mg/ml)
- Opioid (commonly sufentanil 0.2 μg/ml or fentanyl 2 μg/ml)
This combination provides superior analgesia compared to either agent alone, as demonstrated in studies showing that adding fentanyl to bupivacaine markedly improves thoracic epidural analgesia even at low doses 2.
Clinical Efficacy
Thoracic epidural analgesia at these infusion rates has demonstrated:
- Superior pain control at rest and during mobilization
- Reduced incidence of nausea and vomiting
- Shorter duration of postoperative ileus 1
Safety Considerations
When administering thoracic epidural infusions, be aware of these important safety considerations:
- Higher infusion rates may increase the risk of hypotension, which is more common with thoracic epidural compared to paravertebral blocks 1
- Monitor for respiratory depression, especially when opioids are included in the solution
- Be vigilant for catheter migration and potential intravascular or intrathecal injection
- Failure to identify the epidural space occurs in approximately 14.6% of cases 1
Practical Application
For optimal thoracic epidural management:
- Start with an initial infusion rate of 5 ml/h
- Titrate up to a maximum of 10 ml/h based on pain control
- Allow patient-controlled boluses of 5 ml with a 40-minute lockout interval
- Adjust the infusion rate based on the patient's hemodynamic status and pain control
While some studies have used higher flow rates for epidural infusions (up to 250-500 ml/h for programmed intermittent boluses), these were specifically for labor analgesia and not recommended for thoracic epidurals 3.