title: Direct observation during surgery shows preservation of cerebral microcirculation in patients with traumatic brain injury.
abstract: OBJECTIVE
  To describe the alterations of the cortical microcirculation of the brain (blood flow and vessel density) in TBI patients who and compare them with a control group.
  
  
  METHODS
  Prospective and observational study in a third-level university hospital. Cortical microcirculation in the brain was directly observed using sidestream dark-field (SDF) imaging in 14 patients who underwent surgery: 5 subdural hematomas (SDH) and 9 parenchymal lesions (contusions/hematomas). In this last set of patients, images were recorded in the "pericontusional" areas and in the "surrounding" brain (areas that were as far from the lesion as the craniotomy allowed). These patients were compared to five patients who underwent craniotomy for a disease that did not affect the cortex.
  
  
  RESULTS
  There were fewer "pericontusional" images that could be analyzed due to the presence of subarachnoid hemorrhage. The proportion or perfused vessels was similar in all groups: control 99.5% ± 1.3%; SDH 98.6% ± 2.4%; "pericontusional" area 98.2% ± 2.4%; "surrounding" area 98.4% ± 2.5% (p = 0.145). The perfused vessel density index was smaller in the "pericontusional" area: control 6.5 ± 1.6 l/mm; SDH 6.5 ± 2.5 l/mm; "pericontusional" area 5.4 ± 2.6 l/mm; "surrounding" 6.6 ± 2.1 l/mm (p = 0.07).
  
  
  CONCLUSIONS
  Although the analysis of pericontusional zone was difficult, there were fewer vessels than in the controls and there was no change in the flow. In the surrounding zone and in patients with SDH, we did not document alterations in the microcirculation. Direct imaging of cerebral microcirculation in TBI patients showed that despite serious brain injury the cerebral microcirculation was remarkably well preserved.
authors.affiliation: Neurocritical Care Department, Jackson Memorial Hospital, University of Miami, Miami, FL, USA. Electronic address: juan.perezbacerna@jhsmiami.org.
authors.forename: Jon
authors.initials: J
authors.lastname: Pérez-Bárcena
authors.affiliation: Department of Translational Physiology, Academic Medical Center, University of Amsterdam, The Netherlands. Electronic address: edromay@gmail.com.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Romay
authors.affiliation: Department of Intensive Care Medicine, Son Espases University Hospital, Spain. Electronic address: juanantonio.llompart@ssib.es.
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Llompart-Pou
authors.affiliation: Department of Neurosurgery, Son Espases University Hospital, Spain. Electronic address: javier.ibanez@ssib.es.
authors.forename: Javier
authors.initials: J
authors.lastname: Ibáñez
authors.affiliation: Department of Neurosurgery, Son Espases University Hospital, Spain. Electronic address: marta.brell@ssib.es.
authors.forename: Marta
authors.initials: M
authors.lastname: Brell
authors.affiliation: Department of Neurosurgery, Son Espases University Hospital, Spain. Electronic address: pedro.llinas@ssib.es.
authors.forename: Pedro
authors.initials: P
authors.lastname: Llinás
authors.affiliation: Department of Neurosurgery, Son Espases University Hospital, Spain. Electronic address: elsa.gonzalez@ssib.es.
authors.forename: Elsa
authors.initials: E
authors.lastname: González
authors.affiliation: Department of Neurosurgery, Jackson Memorial Hospital, University of Miami, Miami, FL, USA. Electronic address: amerenda@med.miami.edu.
authors.forename: Amedeo
authors.initials: A
authors.lastname: Merenda
authors.affiliation: Department of Translational Physiology, Academic Medical Center, University of Amsterdam, The Netherlands. Electronic address: c.ince@amc.uva.nl.
authors.forename: Can
authors.initials: C
authors.lastname: Ince
authors.affiliation: Department of Neurosurgery, Jackson Memorial Hospital, University of Miami, Miami, FL, USA. Electronic address: rbullock@med.miami.edu.
authors.forename: Ross
authors.initials: R
authors.lastname: Bullock
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D001930:Brain Injuries / Q000503:physiopathology* / Q000601:surgery; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003399:Craniotomy; D003952:Diagnostic Imaging; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007430:Intraoperative Care; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D011446:Prospective Studies; D018709:Statistics, Nonparametric
keywords: Brain contusion; Microcirculation; Pericontusional penumbra; SDF imaging; Subdural hematoma; Traumatic brain injury