title: Reinforcement of subarachnoid block by epidural volume effect in lower abdominal surgery: A comparison between fentanyl and tramadol for efficacy and block properties.
abstract: BACKGROUND
  Epidural volume extension (EVE) is claimed to increase the block height and decrease the dose requirement for intrathecal drug. However, almost all studies have been done in obstetric population and none actually compares the effect of additional drugs added to epidural volume.
  
  
  METHODS
  Seventy-five (ASA I and II) patients scheduled for lower abdominal surgery were randomly divided into three groups. All groups received intrathecal 10 mg bupivacaine; two groups received additional 10 ml of normal saline epidurally with 25 mg tramadol or 25 mg of fentanyl. Groups were than compared for maximal block height, rate of sensory block regression to T10, and motor block regression to Bromage scale of 0. Time to first analgesia and adverse effects were also compared among the three groups.
  
  
  METHODS
  Seventy-five (ASA I and II) patients scheduled for lower abdominal surgery were randomly divided into three groups. All groups received intrathecal 10 mg bupivacaine; two groups received additional 10 ml of normal saline epidurally with 25 mg tramadol or 25 mg of fentanyl. Groups were than compared for maximal block height, rate of sensory block regression to T10, and motor block regression to Bromage scale of 0. Time to first analgesia and adverse effects were also compared among the three groups.
  
  
  RESULTS
  Groups with EVE had statistically significant higher block height, with a significant faster regression that the control group. However, both fentanyl and tramadol groups were inseparable in respect to motor or sensory block regression. Fentanyl group had maximal time to first analgesia, followed by tramadol and control groups. Hemodynamic alterations were also more common in EVE groups.
  
  
  CONCLUSIONS
  EVE can increase the block height significantly, but it seems to be limited only to the physical property of additional volume in epidural space and fentanyl or tramadol do not seem to differ in their ability to alter block properties.
authors.affiliation: Department of Anaesthesia, All India Institute of Medical Sciences, Delhi, India.
authors.forename: Atiharsh
authors.initials: A
authors.lastname: Mohan
authors.affiliation: Department of Anaesthesia, All India Institute of Medical Sciences, Delhi, India.
authors.forename: Preet Mohinder
authors.initials: PM
authors.lastname: Singh
authors.affiliation: Department of Anaesthesiology, BRD Medical College, Gorakhpur, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Malviya
authors.affiliation: Department of Anaesthesiology, BRD Medical College, Gorakhpur, India.
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Arya
authors.affiliation: Department of Anaesthesiology, IMS, BHU, Varanasi, India.
authors.forename: Dinesh Kumar
authors.initials: DK
authors.lastname: Singh
keywords: Epidural fentanyl vs. tramadol; epidural volume extension; subarachnoid block regression