Table 1. Composition of solutions used in neurosurgery.

Component	D5W	NS	LR	ACF
Na+ (mEq/L)	0	154	130	145
K+ (mEq/L)	0	0	4	2.8
Mg2+ (mEq/L)	0	0	0	2.2
Ca2+ (mEq/L)	0	0	3	2.3
Cl- (mEq/L)	0	154	109	129
HCO3 - (mEq/L)	0	0	0	23.1
P (mM/L)	0	0	0	1.1
Lactate- (mEq/L)	0	0	28	0
Glucose (g/L)	50	0	0	0.61
Osmolality ratio	about 0.9	about 0.9	about 0.9	about 1
pH	about 5.0	about 6.7	about 6.7	about 7.3

Abbreviations: D5W: 5% dextrose solution, NS: Normal saline, LR: Lactated Ringer's solution, ACF: Artificial cerebrospinal fluid.