**5.1 Surgical field preparation**

Awake surgery involves several specialists (neurophysiologists, neuropsychologists, surgeons, anesthesiologists, nurses) that must stay together in the operating room; thus, an adequate distribution of the space is essential. First, the position of the patient must ensure not only its comfort but also access to the surgical field; an access to the airway and vascular catheters; and the possibility to perform the corresponding tasks during the procedure. As in any operation, care must be taken to avoid nerve, vascular, ischemic, and musculo-ligamentous injuries related to compression or traction.

Regarding positioning, the most common position for temporal, insular, and low frontoparietal lesions is the patient lying supine with slight lateralization toward the contralateral side of the lesion with cephalic support (Mayfield®, Integra), with the contralateral arm extended and the ipsilateral resting on the body. If the lesion is in the frontal or parietal lobes, it is also possible to use a semi-sitting supine position.

After confirming that the patient is comfortable, the surgical field is prepared. The first step is to remove the hair that interferes with the opening and closure of the skin incision, preferably with an electric razor, followed by washing with antiseptic shampoo. Then, the skin is cleaned with antiseptic (povidone Iodine or chlorhexidine) for three times. Subsequently, the drapes are placed to isolate the surgical field, preferably using a sterile and transparent paper that is placed toward the basal side; in this way, we allow the surgeon to have visual access to the content that is being shown to the patient in any moment.
