Table 11.

Suggested Indications for Neurological Surgery. ∗The choice between intraparenchymal and intraventricular catheters will be guided by surgical criteria, including ventricular patency, accessibility, and the need for CSF drainage as a therapeutic measure. mGCS = Motor Glasgow Coma Scale; MLS = Midline Shift; ZI = Zumkeller Index (ratio of hematoma volume to estimated tolerable hematoma volume based on CT measurements) (Zumkeller et al., 1996); TBI = Traumatic Brain Injury; ONSD = Optic Nerve Sheath Diameter; NPi = Neurological Pupil Index; MCV = Maximum Constriction Velocity; MCA = Middle Cerebral Artery; PI = Pulsatility Index; EDV = End-Diastolic Velocity.

Craniectomy	Craniotomy	Cisternostomy	External Ventricular Drain	Intraparenchymal ICP ± PbtO2 monitor
Large intracranial hematoma + Zumkeller Index >3	Large intracranial hematoma with Zi < 3	Large peri-mesencephalic tSAH + Persistent impaired intracranial compliance despite optimal medical therapy	GCS ≤8 + Abnormal CT scan∗	GCS ≤8 + Abnormal CT scan∗
Significant cerebral edema on CT imaging			GCS ≤8 + Two or more of the following are present∗: Age >40 years Abnormal motor posturing SBP <90 mm Hg	GCS ≤8 + Two or more of the following are present∗: Age >40 years Abnormal motor posturing SBP <90 mm Hg
Persistent intracranial compliance impairment despite optimal medical therapy, hematoma drainage and/or EVD	Intracranial hematoma of any size without significant cerebral edema on CT + Persistent impaired intracranial compliance despite optimal medical therapy		Patients with moderate to severe TBI in whom serial neurological examinations are not feasible, such as those requiring sedation or mechanical ventilation∗	Patients with moderate to severe TBI in whom serial neurological examinations are not feasible, such as those requiring sedation or mechanical ventilation∗
Posterior fossa hematoma >10 mL and hydrocephalus			Persistent intracranial compliance impairment with normal/near-normal CT despite optimal medical therapy and/or hematoma drainage
Persistent PbtO2 < 20 mmHg not attributable to systemic causes
Other indications: ●Wounds with brain exposure (open brain injury) ●Complex scalp wound associated with underlying skull fracture
Interpretation: ● Large intracranial hematoma: ○ Epidural hematoma >30 mL ○ Intracerebral hematoma or contusion >50 mL ○ Subdural hematoma >10 mm ● Significant cerebral edema: ○ MLS ≥5 mm ○ Basal cistern effacement (grade III edema) ●Intracranial compliance impairment: abnormal findings in any combination of ≥2 non-invasive monitoring systems or abnormal ICP waveform

Note: emergency surgery must be performed immediately in cases of non-responsive unilateral mydriasis.