Pulmonary Effects of Fixation of a Fracture with a Plate Compared with Intramedullary Nailing. A Canine Model of Fat Embolism and Fracture Fixation*

Delayed Internal Fixation of Femoral Shaft Fracture Reduces Mortality Among Patients with Multisystem Trauma

“…In a stratified analysis, they reported a significant increase in the incidence of acute respiratory distress syndrome among patients with chest injuries who were managed with intramedullary nailing early (less than twentyfour hours after admission) as compared with those without chest injuries (33% compared with 7.7%), and a similar, but not significant, difference in mortality (21% compared with 4%), suggesting that patients with chest injuries might benefit from delayed treatment. The notion that intramedullary nailing potentiates the development of acute respiratory distress syndrome and further morbidity among patients who are vulnerable because of thoracic injury has been supported by human and animal studies showing embolization of marrow products during intramedullary nailing [43][44][45][46][47] ; however, the clinical importance of this phenomenon continues to be debated. Several observational studies 5,8 involving patients with thoracic injuries but without femoral shaft fractures as controls have demonstrated no difference in the incidence of acute respiratory distress syndrome or mortality, suggesting that it is the severity of the pulmonary injury, rather than timing or mode of fixation, that determines the likelihood of an adverse outcome.…”

Fat embolism

“…Cement is associated with a much higher incidence of FE, although the incidence is not zero in uncemented prostheses [63]. Bone marrow injection in animal models consistently produces cardiorespiratory signs [64,65] and FE can be induced experimentally by reaming and pressurising the intramedullary space with polymethylmethacrylate cement [66]. Sampling of femoral vein blood has localised the origin of fat macroglobules to the injured extremity [67].…”

“…The relationship between intramedullary pressure and FE has led to the development of specific strategies in trauma surgery [90]. External fixation or fixation with a plate produces less lung injury than intramedullary fixation [66]. After reaming, the pressure generated during nail insertion is similar to that produced by an unreamed nail but the incidence of FE has been shown to be lower when unreamed nails are used.…”

Current Concepts of Respiratory Insufficiency Syndromes After Fracture

“…21 Further studies in animal models have shown that intravascular fat appears to produce a negligible inflammatory response. 27,31,32 The importance of fat as a cause of ARDS in the multiply-injured patient therefore remains in doubt. 33 There is often ample evidence of other secondary triggers for ARDS after injury, 34,35 and the role of FE is difficult to define.…”

“…31,[98][99][100][101] There is some evidence to suggest that patients who have been incompletely resuscitated have a higher incidence of pulmonary complications when the operation is carried out early, 89,102 although it is possible that such patients have a greater initial severity of injury, which is responsible for their poor prognosis. 103 If delayed fixation is used, it is still not clear how long the delay should be, since reliable laboratory markers of the inflammation or occult tissue hypoperfusion are not generally available.…”