Suppression of Electrographic Seizures Is Associated with Amelioration of QTc Interval Prolongation in Patients with Traumatic Brain Injury

Figures

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  Figure 1. Changes in frontopolar electroencephalography monitored with Medtronic BIS ™ device and corrected QT (QTc) interval. The left part of the figure presents an electrographic seizure and ECG with prolonged QTc (577 ms, calculated with Bazett’s formula). The right part of the figure presents ESz suppression following thiopental administration with reduction in the QTc interval (447 ms, calculated with Bazett’s formula). The case shown is a 22 year-old woman who was admitted to the intensive care unit (ICU) for severe TBI. Her Glasgow Coma Score was 6. Computed tomography (CT) showed acute epidural hematoma with intracerebral hemorrhage. Immediately after CT, craniectomy was performed. According to the local ICU protocol, frontopolar electroencephalography (EEG) was used. Controlled CT was performed 24 h after surgery and showed slight cerebral edema with cerebral lesion and intracerebral hematoma in the temporal region. Despite depth sedation (BIS ranged between 10 and 20), EEG showed alternate polyspike and slow wave without clinical symptoms 24 h after the admission to the ICU. The ESz recurred for 2 h. Hence, status epilepticus was diagnosed and continuous thiopental infusion at…

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  Figure 2. Changes in frontopolar electroencephalography monitored with Masimo Root device and corrected QT (QTc) interval. Prolonged QTc interval was noted during ESz, and use of thiopental suppressed the seizure successfully, which was associated with a reduction in the automated QTc (from 643 to 499 ms, calculated with Bazett’s formula, and from 610 to 475 ms and 591 to 471 ms, calculated with Fridericia’s formula and Framingham’s formula, respectively). However, the ECG showed bifid T waves in V4, V5, and V6 leads before suppression and in II, III, aVF, V3, V4, V5, and V6 15 min after ESz suppression, leading to partially spurious automated QTc results. Frontopolar EEG monitoring with the Masimo device showed seizures (upper screenshot) and their spectacular suppression following barbiturate infusion (lower screenshots).

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  Figure 3. A 54-year-old male admitted to the intensive care unit (ICU) for severe TBI. His Glasgow Coma Score was 4. Computed tomography (CT) showed cerebral edema with reduced size of both lateral ventricles. Patient was sedated with continuous infusion of propofol and fentanyl, and hyperosmotic therapy with 15% mannitol was administered. According to the local ICU protocol, non-invasive monitoring including near-infrared spectroscopy (NIRS) and frontopolar electroencephalography (EEG) was applied. Frontopolar EEG and seizures were monitored by the Masimo Root SEDLine device. Despite deep sedation (Patient State Index was 7), the DSA image showed upward y-axis arcs in warmer colors, and the recorded EEG confirmed a polyspike and slow wave. Continuous thiopental infusion at the dose of 50 µg·kg−1·min−1 was used to suppress ESz, after which a serial 12-lead ECG showed a notably reduced QTc interval. The patient was discharged from the ICU 14 days after trauma.