Influence of bone marrow fat embolism on coagulation activation in an ovine model of vertebroplasty.
BACKGROUND
Intraoperative cardiovascular deterioration as a result of pulmonary embolization of bone marrow fat is a potentially serious complication during vertebroplasty. The release of fatty material and thromboplastin from the bone marrow cavity during vertebroplasty may activate the coagulation cascade resulting in thrombogenesis, and pharmacological prophylaxis may therefore prevent cardiovascular complications. Thus, the effects of bone marrow fat embolism on coagulation activation during vertebroplasty were investigated with use of an animal model.


METHODS
Polymethylmethacrylate was injected into three lumbar vertebrae of six sheep in order to force bone marrow fat into the circulation. Invasive blood pressures and heart rate were recorded continuously until sixty minutes after the last injection. Cardiac output, arterial and mixed venous blood gas parameters, and coagulation parameters were measured at selected time-points. Postmortem lung biopsy specimens were assessed for the presence of intravascular fat.


RESULTS
Embolization of bone marrow fat resulted in a sudden and dramatic increase in mean pulmonary arterial pressure and a decrease in mean arterial blood pressure. There were no significant changes in any coagulation parameter from before the injection to after the injection. Intravascular fat and bone marrow cells were present in all lung lobes.


CONCLUSIONS
Injection of polymethylmethacrylate into vertebral bodies caused embolization of bone marrow fat with subsequent transient cardiovascular deterioration, but no changes in coagulation parameters were observed. Thromboembolism did not contribute to the observed cardiovascular changes.
Krebs
Jörg
J
MEM Research Center, Institute for Surgical Technology and Biomechanics, Medical Faculty, University of Bern, Stauffacherstrasse 78, 3014 Bern, Switzerland. jorg.krebs@memcenter.unibe.ch
Ferguson
Stephen J
SJ
Hoerstrup
Simon P
SP
Goss
Ben G
BG
Haeberli
André
A
Aebli
Nikolaus
N
D000818:Animals; D001777:Blood Coagulation / Q000502:physiology; D001843:Bone Cements; D001854:Bone Marrow Cells / Q000473:pathology; D004195:Disease Models, Animal; D004620:Embolism, Fat / Q000150:complications / Q000473:pathology*; D005260:Female; D008168:Lung / Q000473:pathology; D019904:Polymethyl Methacrylate / Q000008:administration & dosage; D011655:Pulmonary Embolism / Q000209:etiology / Q000473:pathology*; D012756:Sheep; D054854:Vertebroplasty
D001843:Bone Cements; D019904:Polymethyl Methacrylate