J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website https://www.jocmr.org

Case Report

Volume 16, Number 6, June 2024, pages 319-323

The Use of Remimazolam During Awake Craniotomy for Seizure Foci Resection in Adolescents: A Case Series

**Table 1.** Clinical Patient Data and Remimazolam Dosing
Demographic data	Neurologic history and concerns	Remimazolam and sedative/analgesic medication dosing	Outcomes
BMI: body mass index; PACU: post-anesthesia care unit; PICU: pediatric intensive care unit; LOS: length of stay.
Gender: female Age: 15 years Weight: 103.9 kg Height: 161.2 cm BMI: 39.98 kg/m² Handedness: left	History of previous resection of a dysembryoplastic neuroepithelial tumor creating motor seizures. One previous traditional craniotomy resulted in left extremity weakness. Awake craniotomy was chosen to avoid surgical impact on the motor cortex.	Dexmedetomidine: loading dose 20 µg followed by infusion at 1 - 1.5 µg/kg/h. Propofol infusion: 20 - 50 µg/kg/min started only during scalp block with local anesthetic. Remifentanil infusion: 0.01 - 0.09 µg/kg/min. Remimazolam infusion started at 10 µg/kg/min without a bolus, increased to 15 µg/kg/min after 25 min and stopped after 129 min. Intraoperative anesthetic events: none. Total procedure time: 338 min.	PACU recovery time: 83 min. Postoperative course: uncomplicated. PICU LOS: 1 day.
Gender: male Age: 16 years Weight: 99.5 kg Height: 183 cm BMI: 29.71 kg/m² Handedness: right	History of left inferior frontal mixed glial neuronal tumor/ganglioglioma and associated focal seizures presents for awake craniotomy for language mapping. Seizures result in aphasia followed by right facial contraction with post-ictal slurred speech. Additionally, the patient has bilateral tonic-clonic seizures in the setting of missed medication doses.	Dexmedetomidine: loading dose 40 µg followed by an infusion at 0.4 - 1.5 µg/kg/h. Remifentanil infusion: 0.01 - 0.5 µg/kg/min. Remimazolam infusion started at 5 µg/kg/min without a bolus, titrated from 2.5 - 5 µg/kg/min and stopped after 25 min of procedure time. Intraoperative anesthetic events: none. Total procedure time: 434 min.	PACU recovery time: 20 min. Postoperative course: uncomplicated. PICU LOS: 2 days.
Gender: male Age: 15 years Weight: 72.3 kg Height: 182.3 cm BMI: 21.76 kg/m² Handedness: right	History of seizure foci within the left inferior posterior temporal gyrus, abutting the superior and inferior angular gyrus. Seizures result in full body stiffening, tonic-clonic movements in the upper and lower extremities followed by upper extremity (left > right) weakness without aphasia. Atypical language representation, with anterior/expressive language areas demonstrating predominantly left-sided activation and posterior/receptive language areas demonstrating bilateral to right sided activation on functional MRI. Therefore, awake craniotomy was pursued.	Dexmedetomidine: loading dose 40 µg followed by an infusion at 0.8 - 1.5 µg/kg/h. Remifentanil infusion: 0.04 - 0.15 µg/kg/min. Remimazolam infusion started at 10 µg/kg/min without a bolus for 36 min and then decreased to 5 µg/kg/min. Infusion was stopped after 184 min of procedure time. Intraoperative anesthetic events: none. Total procedure time: 323 min.	PACU recovery time: 46 min. Postoperative course: uncomplicated. PICU LOS: 1 day.

Table 1. Clinical Patient Data and Remimazolam Dosing

Demographic data

Neurologic history and concerns

Remimazolam and sedative/analgesic medication dosing

Outcomes

BMI: body mass index; PACU: post-anesthesia care unit; PICU: pediatric intensive care unit; LOS: length of stay.

Gender: female
Age: 15 years
Weight: 103.9 kg
Height: 161.2 cm
BMI: 39.98 kg/m²
Handedness: left

History of previous resection of a dysembryoplastic neuroepithelial tumor creating motor seizures. One previous traditional craniotomy resulted in left extremity weakness. Awake craniotomy was chosen to avoid surgical impact on the motor cortex.

Dexmedetomidine: loading dose 20 µg followed by infusion at 1 - 1.5 µg/kg/h.
Propofol infusion: 20 - 50 µg/kg/min started only during scalp block with local anesthetic.
Remifentanil infusion: 0.01 - 0.09 µg/kg/min.
Remimazolam infusion started at 10 µg/kg/min without a bolus, increased to 15 µg/kg/min after 25 min and stopped after 129 min.
Intraoperative anesthetic events: none.
Total procedure time: 338 min.

PACU recovery time: 83 min.
Postoperative course: uncomplicated.
PICU LOS: 1 day.

Gender: male
Age: 16 years
Weight: 99.5 kg
Height: 183 cm
BMI: 29.71 kg/m²
Handedness: right

History of left inferior frontal mixed glial neuronal tumor/ganglioglioma and associated focal seizures presents for awake craniotomy for language mapping. Seizures result in aphasia followed by right facial contraction with post-ictal slurred speech. Additionally, the patient has bilateral tonic-clonic seizures in the setting of missed medication doses.

Dexmedetomidine: loading dose 40 µg followed by an infusion at 0.4 - 1.5 µg/kg/h.
Remifentanil infusion: 0.01 - 0.5 µg/kg/min.
Remimazolam infusion started at 5 µg/kg/min without a bolus, titrated from 2.5 - 5 µg/kg/min and stopped after 25 min of procedure time.
Intraoperative anesthetic events: none.
Total procedure time: 434 min.

PACU recovery time: 20 min.
Postoperative course: uncomplicated.
PICU LOS: 2 days.

Gender: male
Age: 15 years
Weight: 72.3 kg
Height: 182.3 cm
BMI: 21.76 kg/m²
Handedness: right

History of seizure foci within the left inferior posterior temporal gyrus, abutting the superior and inferior angular gyrus. Seizures result in full body stiffening, tonic-clonic movements in the upper and lower extremities followed by upper extremity (left > right) weakness without aphasia. Atypical language representation, with anterior/expressive language areas demonstrating predominantly left-sided activation and posterior/receptive language areas demonstrating bilateral to right sided activation on functional MRI. Therefore, awake craniotomy was pursued.

Dexmedetomidine: loading dose 40 µg followed by an infusion at 0.8 - 1.5 µg/kg/h.
Remifentanil infusion: 0.04 - 0.15 µg/kg/min.
Remimazolam infusion started at 10 µg/kg/min without a bolus for 36 min and then decreased to 5 µg/kg/min. Infusion was stopped after 184 min of procedure time.
Intraoperative anesthetic events: none.
Total procedure time: 323 min.

PACU recovery time: 46 min.
Postoperative course: uncomplicated.
PICU LOS: 1 day.

**Table 2.** Arterial Blood Gas Analysis
	Patient 1	Patient 2	Patient 3
End-tidal CO₂ (mm Hg)	47	41	56
pH	7.30	7.29	7.30
PaCO₂ (mm Hg)	52	54	57
PaO₂ (mm Hg)	88	196	129
HCO₃ (mmol/L)	26	26	28
Base deficit (mmol/L)	1.1	1.7	0.2
O₂ saturation (%)	97	100	99
Sodium (mmol/L)	139	134	139
Potassium (mmol/L)	4.0	4.6	4.0
Ionized calcium (mmol/L)	1.27	1.33	1.24
Glucose (mg/dL)	129	134	112
Hemoglobin (g/dL)	11.3	14.1	14.3

Table 2. Arterial Blood Gas Analysis

Patient 1

Patient 2

Patient 3

End-tidal CO₂ (mm Hg)

7.30

7.29

7.30

PaCO₂ (mm Hg)

PaO₂ (mm Hg)

196

129

HCO₃ (mmol/L)

Base deficit (mmol/L)

1.1

1.7

0.2

O₂ saturation (%)

100

Sodium (mmol/L)

139

134

139

Potassium (mmol/L)

4.0

4.6

4.0

Ionized calcium (mmol/L)

1.27

1.33

1.24

Glucose (mg/dL)

129

134

112

Hemoglobin (g/dL)

11.3

14.1

14.3

**Table 3.** Hemodynamic and Patient Data Immediately Before Discontinuation of the Remimazolam Infusion
Parameter	Patient 1	Patient 2	Patient 3
Heart rate (beats/min)	63	57	65
Blood pressure (mm Hg)	119/61	122/52	125/71
Respiratory rate (breaths/min)	14	11	9
Oxygen saturation (pulse oximeter %)	98%	98%	99%
End-tidal carbon dioxide (mm Hg)	41	43	54
Temperature (°C)	35.6	36	35.6
Fraction of inspired oxygen	0.23	0.25	0.21

Table 3. Hemodynamic and Patient Data Immediately Before Discontinuation of the Remimazolam Infusion

Parameter

Patient 1

Patient 2

Patient 3

Heart rate (beats/min)

Blood pressure (mm Hg)

119/61

122/52

125/71

Respiratory rate (breaths/min)

Oxygen saturation (pulse oximeter %)

98%

99%

End-tidal carbon dioxide (mm Hg)

Temperature (°C)

35.6

Fraction of inspired oxygen

0.23

0.25

0.21