title: The effects of propofol and thiopental continuous infusion on serum potassium disturbances in neurosurgical patients.
abstract: OBJECTIVE
  The potassium disturbance associated with thiopental continuous infusion in neurosurgical patients is well known. However, the effect of propofol continuous infusion on serum potassium levels has not been investigated extensively.
  
  
  METHODS
  We reviewed the medical records of 60 consecutive patients who received coma therapy or deep sedation for intracranial pressure control using either thiopental or propofol between January 2010 and January 2012.
  
  
  RESULTS
  The overall incidence of hypokalemia (K<3.5 mmol/L) was comparable between thiopental and propofol groups (89.2% vs. 82.6%). But, the incidence of moderate to severe hypokalemia (K<3.0 mmol/L) was significantly higher in thiopental group (51.4% vs. 13.0%, p=0.003). The lowest potassium level (2.9 mmol/L vs. 3.2 mmol/L, p=0.020) was lower in thiopental group. The patients in the thiopental group required greater potassium replacement than the propofol group patients (0.08 mmol/kg/h vs. 0.02 mmol/kg/h, p<0.001). On multivariate analysis, thiopental [odds ratio, 95% confidence interval, 7.31 (1.78-27.81); p=0.005] was associated with moderate to severe hypokalemia during continuous infusion. The incidence of rebound hyperkalemia (K>5.0 mmol/L, 32.4% vs. 4.3%, p=0.010) and the peak potassium concentration (4.8 mmol/L vs. 4.2 mmol/L, p=0.037) after the cessation of therapy were higher in thiopental group. On multivariate analysis, thiopental [8.82 (1.00-77.81); p=0.049] and duration of continuous infusion [1.02 (1.00-1.04); p=0.016] were associated with rebound hyperkalemia once therapy was discontinued.
  
  
  CONCLUSIONS
  Propofol was less frequently associated with moderate to severe hypokalemia after induction and rebound hyperkalemia following the cessation of continuous infusion than thiopental.
authors: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Tae Kyong
authors: TK
authors: Kim
authors: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Young-Jin
authors: YJ
authors: Lim
authors: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Jae-Woo
authors: JW
authors: Ju
authors: Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.
authors: Jin Wook
authors: JW
authors: Kim
authors: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea.
authors: Hee-Pyoung
authors: HP
authors: Park
keywords: Hyperkalemia; Hypokalemia; Intracranial hypertension; Propofol; Thiopental