An Appropriate Setting for a Patient-Controlled Analgesia Pump for Continuous Local Anesthesia After Bimaxillary Osteotomy
In this report, we aimed to describe an appropriate setting for a patient-controlled analgesia (PCA) pump for postoperative pain control using local anesthetic after bimaxillary osteotomy, which is considered a highly invasive procedure. We conducted a cadaver study to determine the appropriate flow rate setting and then applied our findings to a clinical case. We examined the distribution of local anesthetic administered as ultrasound-guided inferior alveolar nerve blocks (UGIANBs) at different volumes. Using the same UGIANB approach, we placed an indwelling catheter in a healthy male who had undergone bimaxillary osteotomy and set the PCA pump loaded with 0.2% ropivacaine to continuously administer local anesthetic at a flow rate of 7 mL/hour with an additional 5-mL bolus per activation and 30-minute lockout. The patient reported no postoperative pain, did not require other analgesics or antiemetics postoperatively, and had no complications. This approach may have a major impact on clinical practice as it enables opioid-free postoperative analgesia, which may accelerate patient recovery by reducing perioperative complications and shortening hospital stays.
Photograph Showing Staining with Methylene Blue
Dissection of the right mandible reveals the mandibular nerve and the foramen ovale after injection of methylene blue via the UGIANB approach. Abbreviations: UGIANB, ultrasound-guided inferior alveolar nerve block; AT, articular tubercle; ATN, auriculotemporal nerve; FO, foramen ovale; IAN, inferior alveolar nerve; LN, lingual nerve; MF, mandibular fossa; RM, ramus of mandible.
Anterior Local Anesthetic Flow
Local anesthetic (8 or 10 mL) injected into the pterygomandibular space spread anteriorly along the lateral pterygoid muscle, reaching the pterygopalatine fossa. Abbreviations: PF, pterygopalatine fossa; PMS, pterygomandibular space; LPM, lateral pterygoid muscle.
Ultrasound Imaging of the Pterygomandibular Space
Ultrasound imaging taken before needle insertion shows the pterygomandibular space which contains the inferior alveolar and lingual nerves. Abbreviations: Cor, coronoid; Con, mandibular condyle; M, masseter; PMS, pterygomandibular space.
Insertion of the Catheter
With the needle in place, the flexible, indwelling catheter is advanced.
Securing the Catheter
The catheter is secured with adhesive tape once the needle is removed.
Contributor Notes