ABSTRACT
Objective To investigate the effects of 3% hypertonic saline (HTS) on cerebrospinal fluid pressure (CSFP), hemodynamics and electrolytes and the feasibility of reducing intracranial pressure (ICP) with 3% HTS in patients with brain tumor. Methods This study was approved by our institutional ethics committee. Forty consenting ASA Ⅰ or Ⅱ patients of both sexes (23 males, 17 females) undergoing elective surgical excision of supratentorial glioma were randomly divided into 2 groups (n =20 each):3% HTS group and 20% mannitol group. The patients were fasted for 12 h before operation and premedicated with intramuscular phenobarbital 0.1 g and scopolamine 0.3 mg. Anesthesia was induced with midazolam 1.5-2.0 mg, fentanyl 3 ?g?kg-1,2.5% sodium pentothal 4-6 mg?kg-1 and vecuronium 0.1 mg?kg-1. The patients were mechanically ventilated (VT= 8-10 ml?kg-1, RR = 12 bpm, PETCO2 = 30-35 mm Hg) after tracheal intubation. Anesthesia was maintained with isoflurane inhalation and vecuronium infusion at 0.05 mg?kg-1?h-1. A bolus of fentanyl 4 ?g?kg-1 was given i.v. 5 min before incision. Before induction of general anesthesia a 17 G catheter was inserted into subarachnoid space at L3,4 for measurement of CSFP. Left radial artery and right internal jugular vein were cannulated for BP and CVP monitoring and blood sampling. When end-tidal isoflurane concentration was maintained at 1 MAC and hemodynamics stabilized for 15 min,3% HTS 5.35 ml?kg-1 or 20% mannitol 1 g?kg-1 was infused i.v. over 15 min. MAP, HR, CVP and urine output were measured and recorded and arterial blood samples were taken for blood gas analysis and determination of plasma Na+ and K+ concentrations, pH and plasma osmotic pressure before infusion (T0 , baseline) and 15, 30, 60, 90 and 120 min after infusion (T1-5). CSFP was measured at T0-4 and cerebral perfusion pressure (CPP) was calculated (CPP = MAP - ICP).Results The two groups were comparable with regard to sex, age, body weight and the extent of cerebral midline deviation (