Aspectos morfológicos e funcionais do implante de tecido esplênico autógeno previamente conservado em solução de Ringer-lactato

Abstract

Total splenectomy is adopted during the damage control to stop the bleeding of unstable patients with severe splenic traumas. This procedure saves life, however, it does present risks due to the asplenic status, including overwhelming sepsis, thromboembolism, and sudden death.The raising of awareness concerning the importance of the spleen in the organic defense system has inspired the development of conservative operations, such as the partial splenectomy, the subtotal splenectomy, and the autogenous implants of spleen tissue. This investigation proposes a late autogenous implant in an attempt to preserve the functions of the spleen in patients undergoing damage control after severe trauma to the organ. The present work, using an experimental model, evaluated the vitality, morphology, and function of the implanted autogenous spleen tissue the day after the spleen had been removed and to verify a fluid through which the spleen tissue is able to maintain its vitality before the implantation. This study analyzed 35 male rats (Rattus norvegicus albinus), distributed in seven groups: Group 1: without splenectomy; Group 2: total splenectomy; Group 3: total splenectomy, combined with an implant of autogenous spleen tissue on the greater omentum immediately after removal of the spleen; Group 4: total splenectomy, combined with the preservation of the entire spleen in lactated Ringers solution at room temperature for 24 hours; next, the spleen was sliced and implanted on the greater omentum; Group 5: total splenectomy, followed by the sectioning of the spleen in five sections, which were preserved in lactated Ringers solution at room temperature; after 24 hours, the spleen sections were implanted on the greater omentum; Group 6: total splenectomy with the preservation of the entire spleen in lactated Ringers solution at 4°C for 24 hours; next, the spleen was sliced and implanted on the greater momentum; Group 7: total spenectomy, followed by the sectioning of the spleen in five slices, which were preserved in lactate Ringers solution at 4°C; after 24 hours, the spleen sections were implanted on the greater omentum. After 90 days, scintigraphic studies were performed on the liver, lungs, spleen or implants, and a blood clot, with hematologic (erythrogram, fractioned leucometry, and platelet doses), biochemical (protein electrophoresis), scintigraphy assessment of the phagocytic function of the implanted splenic tissue using sulphur colloid labled with 99mTc, and anatomopathologic study of liver, lung and splenic implants. The regeneration of the autogenous splenic implants occurred in all of the animals from the groups with spleen preserved at 4ºC, with a well-defined division between the white and red pulps. The outcome of the colloidal tin proved to be higher in groups 1, 3, 6, and 7, as compared to the other groups (p = 0.0003). No difference was observed in the hematimetric values in the seven groups. Protein electrophoresis presented a tendency toward the reduction of the gamma fraction in the group of animals that had undergone splenectomy, as compared to the other operated groups. In conclusion, the spleen tissue conserved in lactated Ringers solution at a temperature of 4ºC for 24 hours maintains its vitality and allows for its functional recovery after having been implanted on the greater omentum.