Table 4. Table of included studies with detail of modality and protocol of lumbar drainage.

TBI = traumatic brain injury, SAH = subarachnoid haemorrhage, ICH = intracerebral haemorrhage, ICP = intracranial pressure, FOM = foramen of Monro

Authors	Cohort	Method	Continuous or Intermittent	Level of drain	Drainage protocol
Abadal Centellas et al., 2007 [29]	n=17 (adults, TBI)	Lumbar drain	Continuous	FOM	Drainage of cerebrospinal fluid (CSF) was done continuously when ICP raised over 20 mm Hg. If ICP dropped below 10 mm Hg, CSF drainage was immediately stopped. When ICP increased to 15 mm Hg, the drainage system was opened again
Bauer et al., 2017 [31]	n=8 (adults, TBI)	Drain or puncture	Mixed	FOM	Lumbar drain with continuous drainage (n=5) or single LP or intermittently open drainage (n=4)
Levy et al., 1995 [32]	n=16 (children, TBI)	Lumbar drain	Continuous	Head	5-15 cm above the head depending on ICP, gradual decompression over 1-3 minutes
Llompart Pou et al., 2011 [33]	n=30 (adults, TBI)	Lumbar drain	Continuous	10-15cm above FOM	When the ICP was over 20 mmHg, CSF was drained continuously with hourly recordings. After the ICP decreased below 10 mmHg, the external lumbar drain was closed, CSF removal stopped and the patient’s head was placed at 0 degrees to minimise the risk of cerebral herniation. When ICP increased above 15 mmHg the system was opened and the patient’s head placed at 30 degrees again to reinitiate removal
Manet et al., 2016 [34]	n=4 (adults, TBI)	Lumbar drain	Continuous	Tragus	A careful initial CSF withdrawal was achieved at a slow rate (mL by mL), in the presence of the attending neurosurgeon and intensivist, with a continuous papillary examination. When ICP acceptable, CSF drainage was fixed 20 cm above the tragus to maintain safe, continuous CSF drainage
Manet et al., 2017 [35]	n=33 (adults, TBI/SAH/ICH)	Lumbar drain	Continuous	10-15 cm above EAM	Initially withdrawn at 1ml/min with pupillary examination until CPP target (60-70) reached. Then set at 10-15 cm above a zero reference set at the level of the foramen of Monro (external acoustic meatus) and adjusted to maintain a continuous flow of drainage, i.e. 5-15 ml/h
Murad et al., 2012 [25]	n=15 (adults, TBI/SAH)	Lumbar drainage	Varied	0 above FOM	Free drainage in some, 10ml per hour in others (no difference between the two groups)
Tuettenberg et al., 2009 [23]	n=100 (adults, TBI/SAH)	Lumbar drainage	Continuous	5cm above FOM	5-20ml CSF carefully aspirated then free drainage until ICP 10-15 regardless of volume
Willemse, 1998 [37]	Adults	Lumbar drainage	Not stated	5-15 cm above FOM	Not stated