title: Intra-pelvic pressure changes after pelvic fracture: A cadaveric study quantifying the effect of a pelvic binder and limb bandaging over a bolster.
abstract: BACKGROUND
  Unstable pelvic fractures can be life-threatening due to catastrophic haemorrhage. Non-invasive methods of reducing and stabilising these injuries include pelvic binder application and also lower limb bandaging over a knee-flexion bolster. Both of these methods help close the pelvic ring and should tamponade bleeding. This study aimed to quantify the intra-pelvic pressure changes that occurred with 3 different manoeuvres: lower limb bandaging over a bolster; a Trauma Pelvic Orthotic Device (T-POD) pelvic binder, and a combination of both.
  
  
  METHODS
  Following a pilot study with 2 soft embalmed cadavers, a formal study with 6 unembalmed cadavers was performed. For each specimen an unstable pelvic injury was created (OA/OTA 61-C1) by dividing the pelvic ring anteriorly and posteriorly. A 3-4cm manometric water-filled balloon was placed in the retropubic space and connected to a 50ml syringe and water manometer via a 3-way tap. A baseline pressure of 8cmH2O (equating to the average central venous pressure) was used for each cadaver. Steady intra-pelvic pressures (more reliably reflecting the pressures achieved following an intervention) were used in the subsequent statistical analysis, using R statistical language and Rstudio. Paired t-test or Wilcoxon's rank sum test were used (depending on the normality of the dataset) to determine the impact of each intervention on the intra-pelvic pressure.
  
  
  RESULTS
  The mean steady intra-pelvic pressures were significantly greater than the baseline pressure for each intervention. The binder and limb bandaging over a bolster alone increased the mean steady pelvic pressures significantly to 24 (SE=5) (p<0.036) and 15.5 (SE=2) (p<0.02)cmH2O respectively. Combining these interventions further increased the mean steady pressure to 31 (SE=7)cmH2O. However, this was not significantly greater than pressures for each of the individual interventions.
  
  
  CONCLUSIONS
  Both lower limb bandaging over a bolster and pelvic binder application significantly increased intra-pelvic pressure above the baseline pressure. This was further increased through combining these interventions, which could be useful clinically to augment haemorrhage control in these fractures.
  
  
  CONCLUSIONS
  Lower-limb bandaging over a bolster, and pelvic binder application, both significantly increased intra-pelvic pressures, and were greatest in combination. These findings support the use of these techniques to facilitate non-surgical haemorrhage control.
authors.affiliation: Department of Trauma and Orthopaedics, Morriston Hospital, Swansea, SA6 6NL, United Kingdom. Electronic address: rm502@doctors.org.uk.
authors.forename: Rhys
authors.initials: R
authors.lastname: Morris
authors.affiliation: Foundation Year 2 Critical Care, Department of Anaesthesia and Critical Care, Heartlands Hospital, Birmingham, B9 5SS, United Kingdom. Electronic address: andrew.loftus.gem@gmail.com.
authors.forename: Andrew
authors.initials: A
authors.lastname: Loftus
authors.affiliation: Swansea University, Singleton Park, Swansea, SA2 8PP, United Kingdom. Electronic address: y.friedmann@swansea.ac.uk.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Friedmann
authors.affiliation: Department of Trauma and Orthopaedics, Queen Elizabeth Hospital, Birmingham, B15 2TH, United Kingdom. Electronic address: parker_paul@hotmail.com.
authors.forename: Paul
authors.initials: P
authors.lastname: Parker
authors.affiliation: Department of Trauma and Orthopaedics, Morriston Hospital, Swansea, SA6 6NL, United Kingdom. Electronic address: ianpallister@hotmail.com.
authors.forename: Ian
authors.initials: I
authors.lastname: Pallister
mesh_terms: D034841:Abdominal Cavity / Q000473:pathology*; D002102:Cadaver; D003161:Compartment Syndromes / Q000517:prevention & control*; D005592:Fracture Fixation / Q000379:methods; D050723:Fractures, Bone / Q000601:surgery*; D006470:Hemorrhage / Q000517:prevention & control*; D006801:Humans; D008297:Male; D009989:Orthotic Devices / Q000706:statistics & numerical data; D010384:Pelvic Bones / Q000293:injuries / Q000601:surgery*; D010865:Pilot Projects; D011312:Pressure; D012187:Retroperitoneal Space / Q000473:pathology*
keywords: Bolster; Haemorrhage; Limb bandaging over a bolster; Pelvic binder; Pelvic fracture; Trauma