Impact of Fat Graft Thickness and Harvesting Technique on Adipocyte Viability in a New Porcine Experimental Model: An Immunohistochemical Analysis.

BACKGROUND: Autologous fat grafting (AFG) has been employed in surgical practice as a filling method. However, controversies remain on the specifics of this technique. So far, few relevant experimental large animal studies have objectively assessed factors related to AFG integration. OBJECTIVES: This study utilized an experimental, medium-sized animal model to compare the feasibility of AFG collected employing 2 different techniques with instruments of distinct thicknesses. METHODS: Twenty minipigs (Sus scropha domesticus) were subjected to AFG harvesting via en bloc resection utilizing 3- (Group I) and 5-mm-diameter (Group II) round punch blades (PBs) and liposuction (LS) with 3- (Group III) and 5-mm-diameter cannulas (Group IV). Both samples were grafted intramuscularly (biceps femoralis). Hematoxylin and eosin staining was employed to identify intact adipocytes, fat necrosis, fibrosis, inflammation, and oil cysts. Immunohistochemical staining (perilipin-A, tumor necrosis factor alfa, and cluster of differentiation number 31) was utilized to quantify the feasibility of adipocytes, tissue necrosis, and neoangiogenesis, respectively. RESULTS: Hematoxylin and eosin analysis showed that fat necrosis and histiocyte presence were significantly lower in the AFG harvested utilizing a PB than in LS. For perilipin-A, a statistical difference was observed between subgroups I and III (P = 0.001) and I and IV (P = 0.004). Instrument diameter had no effect on graft integration in comparisons between groups II and III (P = 0.059) and II and IV (P = 0.132). CONCLUSIONS: In this experimental study, fat collected utilizing a PB demonstrated higher adipocyte viability than fat collected with LS. The diameter of the collection instruments, whether PB or LS, had no effect on graft integration.

Influence of advanced age on postoperative outcomes and total loss following breast reconstruction: a critical assessment of 560 cases.

OBJECTIVE: to evaluate the role of age in the risk of postoperative complications in patients submitted to unilateral breast reconstruction after mastectomy, with emphasis on total reconstruction loss. METHODS: we conducted a retrospective study of patients submitted to breast reconstruction, whose variables included: oncological and reconstruction data, postoperative complications, including loss of reconstruction and complications of surgical wound. We divided the patients into two groups, according to the classification of the Brazilian National Elderly Policy and the Statute of the Elderly: young (age <60 years) and elderly (60 years or more). We also grouped them according to the World Health Organization classification: young people (age <44 years), middle age (45-59 years); elderly (age 60-89 years) and extreme advanced age (90 years or older). We applied the surgical risk classification of the American Society of Anesthesiologists to investigate the role of the preoperative physical state as a possible predictor of complications. RESULTS: of the 560 patients operated on, 94 (16.8%) were 60 years of age or older. We observed a local complication rate of 49.8%, the majority being self-limited. The incidences of necrosis, infection and dehiscence were 15.5%, 10.9% and 9.3%, respectively. Patients older than 60 years presented a chance of complication 1.606 times greater than the younger ones. Forty-five (8%) patients had loss of the reconstruction; there was no statistically significant difference in the mean age of the patients who presented this result or not (p=0.321). CONCLUSION: in selected patients, breast reconstruction can be considered safe; most documented complications were limited and could be treated conservatively.

Influence of advanced age on postoperative outcomes and total loss following breast reconstruction: a critical assessment of 560 cases / Influência da idade avançada sobre a evolução pós-operatória e a perda total da reconstrução mamária: análise crítica de 560 reconstruções

ABSTRACT Objective: to evaluate the role of age in the risk of postoperative complications in patients submitted to unilateral breast reconstruction after mastectomy, with emphasis on total reconstruction loss. Methods: we conducted a retrospective study of patients submitted to breast reconstruction, whose variables included: oncological and reconstruction data, postoperative complications, including loss of reconstruction and complications of surgical wound. We divided the patients into two groups, according to the classification of the Brazilian National Elderly Policy and the Statute of the Elderly: young (age <60 years) and elderly (60 years or more). We also grouped them according to the World Health Organization classification: young people (age <44 years), middle age (45-59 years); elderly (age 60-89 years) and extreme advanced age (90 years or older). We applied the surgical risk classification of the American Society of Anesthesiologists to investigate the role of the preoperative physical state as a possible predictor of complications. Results: of the 560 patients operated on, 94 (16.8%) were 60 years of age or older. We observed a local complication rate of 49.8%, the majority being self-limited. The incidences of necrosis, infection and dehiscence were 15.5%, 10.9% and 9.3%, respectively. Patients older than 60 years presented a chance of complication 1.606 times greater than the younger ones. Forty-five (8%) patients had loss of the reconstruction; there was no statistically significant difference in the mean age of the patients who presented this result or not (p=0.321). Conclusion: in selected patients, breast reconstruction can be considered safe; most documented complications were limited and could be treated conservatively.

RESUMO Objetivo: avaliar o papel da idade no risco de complicações pós-operatórias de pacientes submetidas à reconstrução mamária unilateral pós-mastectomia, com ênfase na perda total da reconstrução. Métodos: estudo retrospectivo de pacientes submetidas à reconstrução mamária, cujas variáveis incluídas foram: dados oncológicos e da técnica de reconstrução, complicações pós-operatórias, incluindo perda da reconstrução e complicações da ferida operatória. As pacientes foram divididas de acordo com a classificação da Política Nacional do Idoso e Estatuto do Idoso em dois grupos: jovens (idade <60 anos) e idosas (60 anos ou mais). Também foram agrupadas de acordo com a classificação da Organização Mundial da Saúde: jovens (idade <44 anos); meia-idade (idade 45-59 anos); idosas (idade 60-89 anos) e velhice extrema (90 anos ou mais). A classificação do risco cirúrgico da Sociedade Americana de Anestesiologistas foi aplicada para investigar o papel do estado físico pré-operatório como possível preditor de complicações. Resultados: das 560 pacientes operadas, 94 (16,8%) apresentavam 60 anos ou mais. Observou-se taxa de complicações locais de 49,8%, a maioria, limitadas. As incidências de necrose, infecção e deiscência foram de 15,5%, 10,9% e 9,3%, respectivamente. Pacientes com 60 anos ou mais apresentaram chance de complicação 1,606 vezes maior do que as jovens. Quarenta e cinco (8%) pacientes apresentaram perda da reconstrução e não houve diferença estatisticamente significante na média de idade das pacientes que apresentaram ou não esse desfecho (p=0,321). Conclusão: em pacientes selecionadas, a reconstrução mamária pode ser considerada segura; a maioria das complicações documentadas foi limitada e pode ser tratada conservadoramente.

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.

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.

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.