The Effect of Mannitol on the Serum Potassium During Craniotomy

The Effect of Mannitol on Intraoperative Serum Potassium in Patients Undergoing Craniotomy：an Observational Study

This is an observational study designed to research the effect of mannitol on the concentration of intraoperative serum potassium in patients undergoing craniotomy, and to guide the safe use of mannitol during craniotomy.

Patients were assigned to receive 20% mannitol (1g/kg) solution administered intravenously 15-20 minutes at the time of drilling skull.The serum potassium was measured by arterial blood gas analysis before infusion (T0), infusion finished (T1), 15min (T2), 30min (T3), 60min (T4) and 120min (T5) after infusion.

Inclusion Criteria:

• age 18 to 70
• American Society of Anesthesiologists physical status I to II
• liver and kidney function is normal
• preoperative concentration of serum potassium was from 3.5 to 5.5 mmol/L

Exclusion Criteria:

• history or presence of congestive heart failure (New York Heart Association class III to IV)
• history or presence of renal failure(diabetes insipidus, or syndrome of inappropriate antidiuretic hormone secretion)
• intraoperative blood transfusion