title: Efficacy and Safety of a Lidocaine and Ropivacaine Mixture for Scalp Nerve Block and Local Infiltration Anesthesia in Patients Undergoing Awake Craniotomy.
abstract: BACKGROUND
  Mixtures of various local anesthetics, such as lidocaine and ropivacaine, have been widely used. However, their efficacy and safety for scalp nerve blocks and local infiltration during awake craniotomy have not been fully elucidated.
  
  
  METHODS
  We prospectively investigated 53 patients who underwent awake craniotomy. Scalp block was performed for the blockade of the supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, greater occipital, and lesser occipital nerves with a mixture containing equal volumes of 2% lidocaine and 0.75% ropivacaine, including 5 μg/mL of epinephrine. Infiltration anesthesia was applied at the site of skin incision using the same mixture. The study outcomes included changes in heart rate and blood pressure after head pinning and skin incision, and incidence of severe pain on emergence from anesthesia. Total doses and plasma concentrations of lidocaine and ropivacaine were measured at different time points after performing the block.
  
  
  RESULTS
  The heart rate and blood pressure after head pinning were marginally, but significantly, increased when compared with baseline values. There were no significant differences in heart rate and blood pressure before and after the skin incision. Nineteen percent of the patients (10/53) complained of incisional pain at emergence from anesthesia. The highest observed blood concentrations of lidocaine and ropivacaine were 1.9±0.9 and 1.1±0.4 μg/mL, respectively. No acute anesthetic toxicity symptom was observed.
  
  
  CONCLUSIONS
  Scalp block with a mixture of lidocaine and ropivacaine seems to provide effective and safe anesthetic management in patients undergoing awake craniotomy.
authors.affiliation: *Department of Anesthesiology, Sapporo Medical University School of Medicine, Sapporo‡Department of Clinical Pharmaceutics, Hokkaido Pharmaceutical University School of Pharmacy, Otaru, Hokkaido, Japan†Department of Anesthesiology, Penn State Hershey Medical Center, Hershey, PA.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Chaki
authors.forename: Shigekazu
authors.initials: S
authors.lastname: Sugino
authors.forename: Piotr K
authors.initials: PK
authors.lastname: Janicki
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Ishioka
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Hatakeyama
authors.forename: Tomo
authors.initials: T
authors.lastname: Hayase
authors.forename: Miki
authors.initials: M
authors.lastname: Kaneuchi-Yamashita
authors.forename: Naonori
authors.initials: N
authors.lastname: Kohri
authors.forename: Michiaki
authors.initials: M
authors.lastname: Yamakage
mesh_terms: D000577:Amides; D000772:Anesthesia, Local / Q000379:methods*; D000779:Anesthetics, Local; D001794:Blood Pressure / Q000187:drug effects; D003399:Craniotomy; D004359:Drug Therapy, Combination; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008012:Lidocaine; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D011446:Prospective Studies; D000077212:Ropivacaine; D012535:Scalp / Q000187:drug effects / Q000601:surgery; D016896:Treatment Outcome; D014851:Wakefulness
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D008012:Lidocaine