Administration of Human Recombinant Bone Morphogenetic Protein-2 for Spine Fusion May Be Associated With Transient Postoperative Renal Insufficiency

Study Design. Retrospective chart review. Objective. We reviewed the peri- and postoperative outcomes of our patients who had undergone lumbar and lumbosacral fusion both with and without recombinant human bone morphogenetic protein (rhBMP) over a period of 8 years to assess the frequency of complications and new diagnoses associated with the use of rhBMP2. Summary of Background Data. Administration of rhBMP2 for augmentation of lumbar and lumbosacral spinal fusion has not previously been associated with systemic complications. Methods. A review of all patients undergoing lumbar and lumbosacral fusion over an 8-year period was performed to determine the frequency of postoperative complications and new diagnoses. Comparisons in complication frequency and new postoperative diagnoses between patients receiving rhBMP2 versus only allo- or autograft were made. Statistical methodology was applied to determine significance. Results. None of the 105 patients not receiving rhBMP2 and 3 of 24 patients receiving rhBMP2 had blood urea nitrogens and creatinines that more than doubled and reached values >30 and 1.5 mg/dL, respectively, after surgery (P = 0.006). Renal parameters returned to baseline within 45 days of surgery. Two of the 3 patients with postoperative renal insufficiency had been administered 16 mL (24 mg) of rhBMP2, whereas all other patients receiving rhBMP2 had received 8 mL (12 mg). Both of these patients also had supraventricular tachycardia, fever, and mental status changes after surgery. We recorded no significant increase in the incidence of new endocrinologic, autoimmune, neurologic, or neoplastic disorders associated with the use of rhBMP2 in our small patient population. Conclusion. A small subset of patients may develop transient renal insufficiency after rhBMP2 to augment spinal fusion. Higher doses of rhBMP2 may possibly increase the risk of developing renal insufficiency in particular patients; however, additional study is needed before all the risk factors are understood.