Analgetic Effectiveness of a Lidocaine Loaded Hemostatic, Bioresorbable Putty

Overview

The goal of this study was to test the efficacy of local analgesic (lidocaine) loaded hemostatic putty in reducing donor site pain following the harvest of pelvic bone grafts. In 14 patients undergoing harvest of a pelvic bone graft during foot surgery, the bone defect at the pelvis was either filled with a lidocaine loaded hemostatic putty (Orthostat-L) or the same putty without lidocaine (Orthostat, currently marketed as Hemabsorb). Postoperatively, foot pain was eliminated with a peripheral nerve block, while pelvis pain was quantified with two commonly used pain rating scales (VAS and Wong Baker). Blood samples were collected at regular time intervals to measure lidocaine levels. Patients which received the lidocaine loaded putty experienced significantly less pain during the first 12 hours after surgery as compared to those patients who received the lidocaine deficient putty. Blood lidocaine levels always stayed below the toxic threshold.

The harvest of iliac crest bone grafts (ICBG) is associated with relevant donor site pain, but may be lowered by the local application of a biodegradable, hemostatic putty loaded with Lidocaine (=Orthostat-L ™) for sustained local analgesic release. The primary goal of this double-blind controlled trial was to assess the efficacy of the addition of Lidocaine to a hemostatic putty in reducing donor site pain following ICBG in foot and ankle procedures. In 14 patients undergoing ICBG harvest during a foot and ankle procedure, the bone defect at the iliac crest was either filled with Orthostat-L™ (n=7) or with the same hemostatic putty without Lidocaine (Orthostat ™, n=7; currently marketed as HemasorbTM). Postoperatively, donor site pain was managed by patient controlled morphine delivery while surgical site pain was eliminated by a peripheral nerve block. During the first 72 postoperative hours, donor site pain was quantified every 4 hours using a Visual Analog Scale (VAS) and the Wong Baker FACES pain rating scale. In addition, cumulated morphine doses required by the patients and serum Lidocaine levels were registered. Pain scores were plotted over time to calculate the area under the curve (AUC) as a representative of the overall pain experienced within specific time points. There were no significant differences in bone graft size, putty amount and cumulated morphine use between the two groups. Orthostat-L™ provided a significant overall harvest site pain reduction over the first 12 hours postoperatively as evidenced by a significant decrease of the AUC in both VAS and Wong Baker FACES pain score plots (p=0.0366 and p = 0.0024, respectively). After 12 hours, pain scores rapidly returned to baseline levels in both groups. Serum Lidocaine consistently remained below the level of toxicity of 6mg/l. In conclusion, the addition of Lidocaine to a hemostatic putty offers a significant ICBG harvest site pain reduction over the first 12 postoperative hours and appears to be safe in clinical use.