Anesthesia scalp

In scalp-reduction surgery, hyaluronidase lias been combined with die local anesthetics to facilitate their diffusion, to enhance the anesthesia, and to ease the dissection [124]. 

Simultaneous scalp and depth electrode recordings were performed on five patients with complex partial epilepsy who underwent alfentanil anesthesia induction before depth electrode removal (7). Five equal bolus doses of alfentanil 100 gg were given to each patient at 60-second intervals (total dose 500 gg). Epileptiform activity was increased in three of the five, but without clinical evidence of seizure activity. 

In 54 patients who received peribulbar anesthesia with either 1% ropivacaine or a mixture of 0.75% bupivacaine + 2% lidocaine there was no significant difference in akinesia scores or adverse effects reported the following day, notably headache, dizziness, nausea, scalp anesthesia, and diplopia, the latter occurring in 26% and 30% respectively (321). 

For larger tumors, multiple tumors, and tumors in areas where it may be difficult to apply sufficient local anesthesia (e.g., periost involvement in the scalp), general anesthesia is recommended. This may be handled by short-acting anesthetic agents such as propofol combined with short-acting opioids [15]. As pulses should be administered within approximately a 20 min window, the anesthesia can be short and the pahent discharged on the same day [9]. 

Field block anesthesia is produced by subcutaneous injection of a solution of local anesthetic in order to anesthetize the region distal to the injection. For example, subcutaneous infiltration of the proximal portion of the volar surface of the forearm results in an extensive area of cutaneous anesthesia that starts 2-3 cm distal to the site of injection. The same principle can be applied with particular benefit to the scalp, the anterior abdominal wall, and the lower extremity. The drugs, concentrations, and doses recommended are the same as for infiltration anesthesia. The advantage of field block anesthesia is that less drug can be used to provide a greater area of anesthesia than when infiltration anesthesia is used. 

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