Qualitative analysis of the viability of autogenous fat grafts grafted in different environments of interstitial pressure. Preliminary results and description of a new experimental model in mini-pigs

Abstract Purpose: To evaluate the feasibility of an experimental model of autologous fat graft (AFG) in different interstitial pressure (IP) environments. Methods: Three mini-pigs(Minipig-BR) with age of 8 months (weight: 25-30 kg) were used. AFG were collected from the bucal fat pad, and grafted in the intramuscular pocket (biceps femoralis muscle). IP model was based on a fusiform ressection followed by primary closure "under tension". A blood pressure catheter located in the intramuscular region connected to a pressure module was applied to quantify IP. Results: The mean operative time was 236 min (210 - 272 min). All the AFG and muscular segments were removed successfully. Average interstitial pressure CP and H were 3 and 10.6 mmHg respectively. The AFG were biopsied for histopathological analysis 30 days after graft. Hematoxylin-eosin staining and immunohistochemical analyzes (TNF-alpha, CD31 and Perilipine with monoclonal antibodies) were employed. Conclusion: The data show that minipigs model could be used as a recipient site for autologous fat graft techniques and allow the development of studies to explore the AFG intake and pathophysiology response.

Avaliação do índice de infecção de implantes mamários utilizados na reconstrução de mama do Instituto do Câncer do Estado de São Paulo / Evaluation of the infection rate of implants used for breast reconstruction at the Cancer Institute of the State of São Paulo

INTRODUÇÃO: A utilização de implante mamário é a forma de reconstrução de mama mais comumente realizada. Apesar de suas vantagens, a infecção do implante, seja este expansor tecidual ou prótese mamária, pode ser um problema significativo, incluindo a necessidade de sua retirada. O objetivo deste trabalho é avaliar o índice de infecção de implantes mamários utilizados na reconstrução de mama de pacientes operadas no Instituto do Câncer do Estado de São Paulo (ICESP), bem como sua correlação com aspectos clínicos, oncológicos e cirúrgicos. PACIENTES E MÉTODOS: Estudo retrospectivo de 120 pacientes submetidas à reconstrução mamária com implante mamário no ICESP, no período de fevereiro de 2009 a março de 2010. RESULTADOS: O índice de infecção foi de 24,3% e esteve relacionado estatisticamente a reconstrução imediata (88,9%), diabetes mellitus (25%), IMC acima de 30 (52,8%), HAS (52,8%) e sofrimento de pele da mastectomia (27,8%). Nota-se que 44% dos implantes infectados foram retirados, sendo a maioria expansores colocados em reconstrução imediata. CONCLUSÕES: A reconstrução mamária com implante é uma forma segura e eficaz de tratamento. Deve-se, entretanto, estar atento aos subgrupos de pacientes mais propensas ao desenvolvimento de infecção, para otimizar a sua prevenção e atentar ao seu tratamento precoce.

INTRODUCTION: Placement of breast implants is the most commonly used form of breast reconstruction. Despite its advantages, infection of the implant, either in the tissue expander or mammary prosthesis, can be a significant problem, including the need to remove it. The objective of this work is to evaluate the infection rate of breast implants used for breast reconstruction in patients submitted to surgery at the Cancer Institute of the State of São Paulo (ICESP), as well as its correlation with clinical, oncological, and surgical factors. PATIENTS AND METHODS: This is a retrospective study on 120 patients submitted to breast reconstruction with breast implants at the ICESP from February 2009 to March 2010. RESULTS: The infection rate (24.3%) was statistically related to immediate reconstruction (88.9%), diabetes mellitus (25%), body mass index >30 (52.8%), systemic arterial hypertension (52.8%), and skin injury due to mastectomy (27.8%). Of the infected implants, 44% were removed, most of which were expanders placed during immediate reconstruction. CONCLUSIONS: Breast reconstruction with implants is the safest and most effective form of treatment. However, consideration should be given to patients who are prone to the development of infection, in order to optimize its prevention and attempt to perform its treatment at an early stage.