Table 3. Adverse events and complications reported in included studies.

TBI = traumatic brain injury, SAH = subarachnoid haemorrhage, ICH = intracerebral haemorrhage, EVD = external ventricular drain, ELD - external lumbar drain, LD = lumbar drainage, CSF = cerebrospinal fluid

Authors	Cohort	EVD?	CSF infections	LD revisions	Number requiring a shunt	Cerebral herniation post-ELD?	Details
Abadal Centellas et al., 2007 [29]	n=17 (adults, TBI)	No	0 (3 contaminants)	2 (5 blockages)	0	n=0	No pupil changes in 24 hours post insertion
Bauer et al., 2017 [31]	n=8 (adults, TBI)	No	None stated	None stated	None stated	n=1	One patient showed an uncal herniation on both sides after lumbar CSF withdrawal without mydriasis or other clinical signs of cerebral herniation
Levy et al., 1995 [32]	n=16 (children, TBI)	Yes in all	None stated	None stated	3	n=0	Two patients had fixed and dilated pupils prior to ELD insertion, remained so after lumbar drainage commenced
Llompart Pou et al., 2011 [33]	n=30 (adults, TBI)	No	1 (4 with positive cultures, 3 contaminant)	4 (8 obstruction)	3	n=0	No pupil changes in 48 hours post insertion
Manet et al., 2016 [34]	n=4 (adults, TBI)	No	0	0	0	n=0	N/A
Manet et al., 2017 [35]	n=33 (adults, TBI/SAH/ICH)	Mixed (8/33)	1	0	5	n=0	N/A
Murad et al., 2012 [25]	n=15 (adults, TBI/SAH)	Yes in all	0	None stated	None stated	n=1	Fixed dilated pupil four hours after ELD insertion, which returned to normal after surgery hours
Tuettenberg et al., 2009 [23]	n=100 (adults, TBI/SAH)	Mixed (84/100)	7 (all also had EVD)	14/100	None stated	n=12	No relationship to ELD described. All had unilateral mydriasis. 4/12 survived. Three patients died from cerebral herniation secondary to intracranial hypertension, three had a devastating injury prior to ELD, one died from pulmonary embolism, one died from cerebral infarction. No reports of morbidity or mortality directly from ELD
Willemse, 1998 [37]	n=7 (adults, TBI)	Yes in all	None stated	None stated	None stated	n=0	N/A