Risk Factors of Tissue-Expander Infection in Breast Reconstruction

PURPOSE: Implant-based breast reconstruction has multiple advantages such as decreased morbidity, shorter operative time and faster recovery. However, postoperative infection with tissue expander increases medical cost and causes a delay in concurrent antineoplastic treatment. To reduce tissue expander infection, it is important to identify related risk factors and minimize them when possible. METHODS: A retrospective review of patient records in a single breast cancer center was performed. Eighty-six tissue expanders were placed in 80 women for postmastectomy breast reconstruction. Variables including patients'age, body mass index(BMI), preoperative breast volume, operation time, drain indwelling time, postoperative seroma/hematoma formation, chemotherapy, and radiation therapy were evaluated. Infection was defined as the status that shows any symptom of local inflammation and identification of pathogens. Representative values were compared through Student's t-test and univariate and multivariate analyses. RESULTS: We examined 86 postmastectomy tissue- expanders which were placed between June 2004 and April 2010. Seven cases of tissue expander infection (8.1%) were identified. The infected tissue expander was removed in three of the cases. The relationship between BMI, and preoperative breast volume and that between infection and non-infection groups were significant(p<0.05). Univariate analysis showed significant association between BMI(p=0.023) and preoperative breast volume (p=0.037). Multivariate analysis revealed that BMI and preoperative breast volume were independent variables regarding tissue expander infection. CONCLUSION: Certain characteristics of implant-based breast reconstruction patients increase infection rate of tissue expander. These risk factors should be monitored and evaluated before surgeries for more successful outcome.

The Effect of Nitric Oxide Donor, SNAC on Motor Functional Recovery of Reperfused Peripheral Nerve / 대한정형외과학회잡지

PURPOSE: To investigate the effects of nitric oxide (NO) donor, S-nitroso-N-acetylcysteine (SNAC) on the motor functional recovery of a reperfused rat sciatic nerve. MATERIALS AND METHODS: Seventy-eight rats were divided into the following 3 groups: SNAC, methylprednisolone (MP), and phosphate buffered saline (PBS)-treated groups. A 1 cm segment of the sciatic nerve underwent 2 hours of ischemia followed by 90 minutes of reperfusion. The results were evaluated using a walking track test, muscle contractile test and an examination of the muscle weight and histology at various reperfusion periods. RESULTS: There was a significant improvement in the sciatic functional index (SFI) and contractile force of the SNAC-treated group compared with the MP and PBS groups. The SNAC group showed earlier improvement in the SFI measurement between days 7-28. The contractile force and muscle weight of the extensor digitorum longus muscle began to be restored earlier in the SNAC group after day 11, while the others showed progressive atrophy until day 21. The histology examination revealed less severe degeneration and earlier regeneration of axons in the SNAC-treated rats than the other groups. CONCLUSION: The supplementation of NO is effective in promoting the motor functional recovery of a reperfused peripheral nerve and has the potential to replace or augment steroids as a therapeutic agent in the treatment of nervous system ischemia/reperfusion injuries.