title: Lidocaine infiltration of the scalp does not completely abolish increased intraocular pressure due to skull pin insertion.
abstract: Insertion of skull pins results in haemodynamic perturbations, which can be blunted by local anaesthetic infiltration of the pin sites. No study has assessed the effects on intraocular pressure. General anaesthesia was induced in 71 patients undergoing cervical spine surgery with attachment of Gardner Wells tongs to the skull. Skull pins were attached five minutes after induction following either saline (group I, 35 patients) or lidocaine (group II, 36 patients) infiltration of scalp. Intraocular pressure, mean arterial pressure and heart rate were recorded before (baseline), immediately after, and 60 s following pin insertion and analysed statistically. Insertion of pins increased intraocular pressure in both groups (from 8.4+/-2.7 to 14.2+/-3.0 mmHg in group I, and from 8.8+/-2.3 to 12.7+/-2.7 mmHg in group II, P < 0.001), which persisted even at 60 s but the increase was significantly greater in group I. Insertion of pins significantly increased blood pressure in group I only. We conclude that lidocaine infiltration at the skull pin sites for Gardner Wells tong attachment fails to completely abolish increased intraocular pressure.
authors.affiliation: Department of Neuroanaesthesia, Neurosciences Center, All India Institute of Medical Sciences, New Delhi 110 029, India. pkbithal@hotmail.com
authors.forename: P K
authors.initials: PK
authors.lastname: Bithal
authors.forename: M P
authors.initials: MP
authors.lastname: Pandia
authors.forename: A
authors.initials: A
authors.lastname: Chaturvedi
authors.forename: M
authors.initials: M
authors.lastname: Radhakrishnan
authors.forename: H
authors.initials: H
authors.lastname: Prabhakar
authors.forename: D
authors.initials: D
authors.lastname: Sharma
mesh_terms: D000328:Adult; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects; D002493:Central Nervous System Diseases / Q000601:surgery; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects* / Q000502:physiology; D008012:Lidocaine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D009984:Orthopedic Fixation Devices / Q000009:adverse effects*; D012886:Skull / Q000601:surgery*; D013131:Spine / Q000601:surgery; D013997:Time Factors
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine