Pre-emptive Scalp Infiltration With Dexamethasone Plus Ropivacaine for Postoperative Pain After Craniotomy

Pre-emptive Scalp Infiltration With Dexamethasone Plus Ropivacaine vs. Ropivacaine for Relief of Postoperative Pain After Craniotomy in Adults

A majority of patients would suffer from moderate-to-severe postoperative pain after undergoing craniotomy. As a result, adequate pain control is essential for patients' prognosis and their postoperative life quality. Although opioids administration is regarded as the first-line analgesic for post-craniotomy pain management, it may be associated with delayed awakening, respiratory depression, hypercarbia and it may interfere with the neurologic examination. For the avoidance of side-effects of systemic opioids, local anesthetics administered around the incision have been performed clinically. However, some studies revealed that the analgesic effect of local anesthetics was not unsatisfactory due to its short pain relief duration. As is reported that postoperative pain of craniotomy is mainly caused by skin incision and reflection of muscles, preventing the liberation of inflammatory mediators around the incision seems to be more effective than simply blocking nerve conduction. Thus, Investigators suppose that pre-emptive scalp infiltration with steroid (dexamethasone) plus local anesthetic (ropivacaine) could relieve postoperative pain after craniotomy in adults.

Inclusion Criteria:

• Patients scheduled for elective craniotomy for resection of a supratentorial tumour under general anaesthesia;
• American Society of Anesthesiologists (ASA) physical status of I or II;
• Participates required to fix their head in a head clamp intraoperatively;
• Participates with an anticipated fully recovery within 2 hours postoperatively.

Exclusion Criteria:

• History of craniotomy;
• Expected delayed extubation or no plan to extubate;
• Participants who cannot use a patient-controlled analgesia (PCA) device;
• Participants who cannot understand the instructions of a numeral rating scale (NRS) 35 before surgery;
• Extreme body mass index (BMI) (< 15 or > 35);
• Allergy to opioids, dexamethasone or ropivacaine;
• History of excessive alcohol or drug abuse, chronic opioid use (more than 2 weeks), or use of drugs with confirmed or suspected sedative or analgesic effects;
• History of psychiatric disorders, uncontrolled epilepsy or chronic headache;
• Pregnant or at breastfeeding;
• Symptomatic cardiopulmonary, renal, or liver dysfunction or history of diabetes;
• Preoperative Glasgow Coma Scale< 15;
• Suspicion of intracranial hypertension;
• Peri-incisional infection;
• Participants who have received radiation therapy and chemotherapy preoperatively or with a high probability to require a postoperative radiation therapy and chemotherapy according to the preoperative imaging.