title: Ammonia encephalopathy and awake craniotomy for brain language mapping: cause of failed awake craniotomy.
abstract: We report the case of an aborted awake craniotomy for a left frontotemporoinsular glioma due to ammonia encephalopathy on a patient taking Levetiracetam, valproic acid and clobazam. This awake mapping surgery was scheduled as a second-stage procedure following partial resection eight days earlier under general anesthesia. We planned to perform the surgery with local anesthesia and sedation with remifentanil and propofol. After removal of the bone flap all sedation was stopped and we noticed slow mentation and excessive drowsiness prompting us to stop and control the airway and proceed with general anesthesia. There were no post-operative complications but the patient continued to exhibit bradypsychia and hand tremor. His ammonia level was found to be elevated and was treated with an infusion of l-carnitine after discontinuation of the valproic acid with vast improvement. Ammonia encephalopathy should be considered in patients treated with valproic acid and mental status changes who require an awake craniotomy with patient collaboration.
authors.affiliation: Neurosurgery Department, Hospital del Mar, Barcelona, Spain. Electronic address: gloriavillalbamartinez@gmail.com.
authors.forename: G
authors.initials: G
authors.lastname: Villalba Martínez
authors.affiliation: Anesthesiology and Resuscitation Department, Hospital del Mar, Barcelona, Spain.
authors.forename: J L
authors.initials: JL
authors.lastname: Fernández-Candil
authors.affiliation: Neurology Department, Hospital del Mar, Barcelona, Spain.
authors.forename: R M
authors.initials: RM
authors.lastname: Vivanco-Hidalgo
authors.affiliation: Anesthesiology and Resuscitation Department, Hospital del Mar, Barcelona, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Pacreu Terradas
authors.affiliation: Neurophysiology Department, Hospital del Mar, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: León Jorba
authors.affiliation: Anesthesiology and Resuscitation Department, Hospital del Mar, Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Arroyo Pérez
mesh_terms: D000768:Anesthesia, General; D000772:Anesthesia, Local; D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use; D001037:Aphasia / Q000209:etiology; D001569:Benzodiazepines / Q000627:therapeutic use; D001927:Brain Diseases / Q000209:etiology*; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000150:complications / Q000601:surgery*; D002331:Carnitine / Q000627:therapeutic use; D000078306:Clobazam; D016292:Procedural Sedation; D003244:Consciousness Disorders / Q000209:etiology; D003399:Craniotomy / Q000379:methods*; D004292:Dominance, Cerebral; D005625:Frontal Lobe / Q000503:physiopathology / Q000601:surgery*; D005910:Glioma / Q000150:complications / Q000601:surgery*; D006801:Humans; D022124:Hyperammonemia / Q000139:chemically induced / Q000150:complications* / Q000188:drug therapy; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007431:Intraoperative Complications / Q000188:drug therapy / Q000209:etiology*; D007802:Language; D000077287:Levetiracetam; D008297:Male; D008875:Middle Aged; D010880:Piperidines / Q000627:therapeutic use; D010889:Piracetam / Q000031:analogs & derivatives / Q000627:therapeutic use; D015742:Propofol / Q000627:therapeutic use; D000077208:Remifentanil; D012640:Seizures / Q000188:drug therapy / Q000209:etiology; D013702:Temporal Lobe / Q000503:physiopathology / Q000601:surgery*; D014635:Valproic Acid / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D000927:Anticonvulsants; D006993:Hypnotics and Sedatives; D010880:Piperidines; D001569:Benzodiazepines; D000078306:Clobazam; D000077287:Levetiracetam; D014635:Valproic Acid; D000077208:Remifentanil; D002331:Carnitine; D015742:Propofol; D010889:Piracetam
keywords: Ammonia encephalopathy; Ammonia levels; Awake craniotomy; Craneotomía con el paciente despierto; Encefalopatía por amonio; Glioma insular; Insular glioma; Niveles de amonio; Valproic acid; Ácido valproico