title: Hypotensive Epidural Anesthesia Reduces Blood Loss in Pelvic and Sacral Bone Tumor Resections.
abstract: BACKGROUND
  Resection of pelvic and sacral tumors can cause severe blood loss, complications, and even postoperative death. Hypotensive epidural anesthesia has been used to mitigate blood loss after elective arthroplasty, but to our knowledge, it has not been studied as an approach that might make resection of pelvic and sacral tumors safer.
  
  
  OBJECTIVE
  The purposes of this study were (1) to compare the blood loss and blood product use for patients undergoing pelvic and sacral tumor surgery under standard anesthesia or hypotensive epidural anesthesia; (2) to assess the frequency of end-organ damage with the two techniques; and (3) to compare 90-day mortality between the two techniques.
  
  
  METHODS
  Between 2000 and 2014, 285 major pelvic and sacral resections were performed at one center. A total of 174 (61%) had complete data sets for analysis of blood loss, transfusion use, complications, and mortality at 90 days. Of those, 102 (59%) underwent hypotensive epidural anesthesia, whereas the remainder received standard anesthetic care. The anesthetic approach was determined by the anesthetists in charge of the case with hypotensive epidural anesthesia exclusively performed by one of two subspecialty trained anesthetists as their routine for major pelvic or sacral surgery. The groups were comparable in terms of potential confounding variables such as age, gender, tumor volume, and operation performed. Hypotensive epidural anesthesia was defined as a technique using an extensive epidural block up to T2-3 dermatome, peripherally administered low-concentration intravenous adrenaline infusion, and using unimpeded spontaneous respiration to achieve controlled hypotension, precise rate control of the heart, and enhanced velocity of venous return, all aggregated thus to minimize blood loss during pelvic surgery while preserving vital perfusion. The groups were assessed for perioperative blood loss calculated from pre- and postsurgery hemoglobin and transfusion use as well as postoperative complications, morbidity, and mortality at 90 days.
  
  
  RESULTS
  There was less mean blood loss in the hypotensive epidural anesthesia group (1457 mL, SD 1721, 95% confidence interval [CI], 1114-1801 versus 2421 mL, SD 2297, 95% CI, 1877-2965; p = 0.003). Patients in the hypotensive epidural anesthesia group on average received fewer packed red cell transfusions (2.7 units, SD 2.9, 95% CI, 2.1-3.2 versus 3.9 units, SD 4.4, 95% CI, 2.9-5.0; p = 0.03). There were no differences in the proportions of patients experiencing end-organ injury (7%, n = seven of 102 versus 6%, n = four of 72; p = 0.72). With the numbers available, there was no difference in 90-day mortality rate between groups (1.9%, n = two of 102 versus 1.3%, n = one of 72; p = 0.77).
  
  
  CONCLUSIONS
  We found that hypotensive epidural anesthesia resulted in less blood loss, fewer transfusions, and no apparent increase in serious complications in pelvic and sacral tumor surgery performed in the setting of a high-volume tertiary sarcoma referral hospital. We recommend that further collaborative studies be undertaken to confirm our results with hypotensive epidural anesthesia in surgery for pelvic tumors.
  
  
  METHODS
  Level III, therapeutic study.
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Edgbaston, UK.
authors.forename: Alex K
authors.initials: AK
authors.lastname: Freeman
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Edgbaston, UK.
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Thorne
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK.
authors.forename: C Louie
authors.initials: CL
authors.lastname: Gaston
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Shellard
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Neal
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK. michaelcparry@hotmail.com.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Parry
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Grimer
authors.affiliation: The Royal Orthopaedic Hospital NHS Foundation Trust, Bristol Road South, Birmingham, B31 2AP, UK.|School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Lee
authors.initials: L
authors.lastname: Jeys
mesh_terms: D000328:Adult; D000368:Aged; D000767:Anesthesia, Epidural / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D016063:Blood Loss, Surgical / Q000401:mortality / Q000517:prevention & control*; D001803:Blood Transfusion; D005260:Female; D006801:Humans; D007022:Hypotension; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000401:mortality; D019637:Orthopedic Procedures / Q000009:adverse effects / Q000401:mortality; D010386:Pelvic Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D012447:Sacrum / Q000473:pathology / Q000601:surgery*; D013125:Spinal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome