title: Comparison of the effects of colloid preload, vasopressor administration and leg compression on hemodynamic changes during spinal anesthesia for lumbar disc surgery in knee-chest position.
abstract: BACKGROUND
  Hypotension is a serious and the most common adverse effect of spinal anesthesia. Many studies have focused on prevention of hypotension due to spinal anesthesia. The aim of this study was to compare the efficacy of three different methods of using colloid, ephedrine and wrapping of extremities on the incidence of hypotension and bradycardia following spinal anesthesia in patients undergoing elective lumbar disc surgery in knee-chest position.
  
  
  METHODS
  A total of 180, ASA (I-II), adult patients candidate of lumbar disc surgery in one or two levels who met the inclusion criteria were randomly allocated in one of three treatment groups of receiving Voluven (6% hydroxyethyl starch 130/0.4 in 0.9% sodium chloride injection), ephedrine and leg wrapping. After establishment of spinal anesthesia, patients were outsourced and knee-chest position was done. Heart rate and blood pressure of patients were recorded at different times till 60 min after spinal injection. Statistical analyses of data were performed with SPSS (version 20) and by considering groups, values of P < 0.05 were considered statistically significant.
  
  
  RESULTS
  Mean systolic blood pressure (119.5 ± 7.4 mmHg) and mean heart rate (71.7 ± 6.7 b/min) were higher in a group receiving Voluven (P < 0.05). The Voluven group significantly experienced less nausea and vomiting in recovery room in comparing with other groups (P = 0.027). They also received significantly less ephedrine (P = 0.012) and ondansetron [12 (20%)] (P = 0.02). Furthermore, patients receiving elastic bandage had significantly more blood loss than the other groups (P = 0.013).
  
  
  CONCLUSIONS
  Colloid therapy was the most effective method in keeping hemodynamic stability, prevention of decrease in systolic blood pressure and incidence of side effects during spinal anesthesia for lumbar disc surgery in knee-chest position.
authors.affiliation: Department of Anesthesiology and Critical Care, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Reihanak
authors.initials: R
authors.lastname: Talakoub
authors.affiliation: Department of Anesthesiology and Critical Care, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Abdolrahman
authors.initials: A
authors.lastname: Fani
authors.affiliation: Department of Anesthesiology and Critical Care, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Anahita
authors.initials: A
authors.lastname: Hirmanpour
keywords: Colloid; colloid preload; ephedrine; hemodynamic changes; knee-chest position; leg wrapping; lumbar disc surgery; spinal anesthesia