Pain during awake craniotomy for brain tumor resection. Incidence, causes, consequences and management

Awake craniotomy for brain tumor resection is usually well-tolerated and most of the patients are satisfied. However, in studies reporting the patients' postoperative perception of the awake craniotomy procedure, about half of them have experienced some degree of intraoperative pain. Pain was mild (intensity between 1 and 2 on the visual analogical score) short lasting in most cases, and did not challenge the procedure. Pain was reported as moderate in about 25% and exceptionally severe.

We conducted a preliminary survey among French centers (n=9) routinely performing awake craniotomy.

Neurosurgeons' opinions were concordant with patient's reports. Intraoperative pain exceptionally challenged the awake craniotomy procedure or led to changes in the resection strategy. For neurosurgeons, the most challenging causes of intraoperative pain were the patient's inadequate installation, the contact of surgical tools with pain-sensitive intracranial structures, especially the dura mater of the skull base, falx cerebri, and the leptomeninges of the lateral fissure and neighboring sulci.

Strategies to deal with these causes included focusing the patient on the intraoperative functional tests to distract their attention away from the pain, and avoiding contacts with the pain-sensitive intracranial structures during the awake phase. Adequate preoperative patient information and preparation, trained anesthesiologists and application of recommendations for awake craniotomy procedures as well as adaptation of surgical technique to avoid contact with pain-sensitive intracranial structures are key factors to prevent intraoperative pain and ensure patient's postoperative satisfaction.