Intraoperative Generalized Tonic-clonic Seizure While Undergoing General Anesthesia for a Left Temporo-occipital Craniotomy

BACKGROUND: While undergoing general anesthesia for a temporo-occipital craniotomy for primary tumor resection a 38 year-old gentleman had a generalized tonic-clonic seizure. Intraoperative seizures under general anesthesia... [ view full abstract ]

BACKGROUND: 

While undergoing general anesthesia for a temporo-occipital craniotomy for primary tumor resection a 38 year-old gentleman had a generalized tonic-clonic seizure. Intraoperative seizures under general anesthesia are extremely rare and this event occurred despite the patient receiving both oral and intraoperative intravenous levetiracetam. This event was especially concerning given the patient’s head was being held into place with a Mayfield 3-point fixation head holder and surgery was actively being performed. Upon recognition of tonic-clonic type movement propofol and remifentanil boluses were administered with resultant cessation of the seizure that was followed by significant hemodynamic and physiologic variability.

CASE DESCRIPTION:

• 38 year old man with history of mild asthma and seizures was found to have a left temporal occipital junction lesion and underwent general anesthesia for left temporo-occipital craniotomy
• Patient experienced a seizure at work one month prior to surgery, resulting in an inability to read and visual distortion (“flickering TV effect”)
• Seen at an outside hospital for syncope, visual auras, and inability to read - referred to neurologist office, during visit experienced a seizure and was sent to the emergency department 2.5 weeks prior to surgery
• MRI Brain – left 15mm temporal occipital junction lesion with irregular margins
• Pre-operative laboratory values and vitals signs unremarkable
• Normal levetiracetam (Keppra) dose (1000mg BID) taken at 3am on morning of surgery with sip of water
• Patient induced, intubated, positioned in Mayfield 3-point fixation head holder without incident
• Twenty minutes after surgical incision patient experienced a generalized tonic-clonic seizure, remifentanil and levetiracetam were running, and expired sevoflurane was 1.8%
• Upon recognition of tonic-clonic type movement, boluses of propofol and remifentanil were administered with resultant cessation of the seizure
• The remainder of the operative case, postoperative evaluation including neurological exam, and follow up were unremarkable
• Surgical pathology was consistent with glioblastoma and the patient later underwent concomitant radiation and chemotherapy
• Recurrent glioblastoma was detected approximately 6 months after initial surgery for which patient underwent subsequent craniotomy

 DISCUSSION:

• Previous studies have reported intraoperative incidence as low as 3.1 cases per 10,000 and as high as 3.4% among those with a preexisting seizure disorder
• Up to 68% of intraoperative seizures were related to surgery, 55% were attributed to patient-related factors, and 30% were directly associated with anesthesia
• Multidisciplinary approach to effectively manage patients at risk for perioperative seizures
• Determine baseline AED blood levels to ensure perioperative drug compliance and prevent sub-therapeutic levels
• Once a seizure takes place, measures must be taken to prevent progression into convulsive status epilepticus (CSE)
• Benzodiazepines are considered first line drugs for termination of CSE
• In the operating room propofol is considered a reasonable first choice
• If a grand mal seizure occurs, consider rapid onset neuromuscular blocking agents to reduce the risk of injury due to convulsion if the patient is in a Mayfield (i.e. herniation)