Embolization for pediatric blunt splenic injury is an alternative to splenectomy when observation fails.

BACKGROUND: Management of splenic injury has shifted from operative to nonoperative management in both children and adults with reports of high success rates. Benefits of splenic conservation include decreased hospital stay, blood transfusion, and mortality, as well as avoidance of infectious complications. Angiography with embolization is an innovative adjunct to nonoperative management and has resulted in increased splenic salvage in adults; however, data in the pediatric population are scant. METHODS: A retrospective comparative study of a single-hospital trauma registry reviewed from 1999 to 2009. Patients 18 years and younger admitted with injury to the spleen were included. Children with penetrating injury were excluded. Children were divided into three categories by initial treatment: observation, embolization, or splenectomy. Data recorded include age, radiographic grade of injury, and Injury Severity Score (ISS). Groups were analyzed for success of initial treatment, requirement for transfusion of packed red blood cells, splenic salvage, and mortality. RESULTS: Registry review identified 259 children with blunt splenic injury. Initial treatment was observation in 227, embolization in 15, and splenectomy in 17. In the observation group, 9 (4%) of 227 children failed initial treatment; 8 of these underwent embolization, while 1 unerwent splenectomy. In the embolization group, 1 (7%) of 15 failed initial treatment and underwent splenectomy. Blood transfusion was required by 38 (17%) of 227 in the observation group, 6 (40%) of 15 (p = 0.02) in the embolization group, and 15 (88%) of 17 (p < 0.01) in the splenectomy group. Overall splenic salvage rate was 237 (92%) of 259. Three children died in the observation group, and four children died in the splenectomy group. There was no death in the embolization group. CONCLUSION: Splenic artery embolization for blunt trauma in children is associated with a higher blood transfusion rate compared with observation but offers a safe, intermediate alternative to splenectomy when observation fails. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Novel method of stump closure for distal pancreatectomy with a 75% reduction in pancreatic fistula rate.

BACKGROUND: Pancreatic fistula is a significant problem for patients undergoing distal pancreatectomy with fistula rates up to 61%. Fistulas lead to substantial morbidity. The study objective was to compare radiofrequency dissector closure with traditional stump closure for distal pancreatectomy. METHODS: Sixty-two patients underwent distal pancreatectomy at our institution between 2002 and 2011. Thirty-three patients had traditional stump closure compared with 29 patients who had radiofrequency closure. Fistula rates, operative times, and blood loss were compared. The control patients underwent open operation in 20 (60%) cases and laparoscopic operation in the remaining 13 (40%). Of the patients that underwent radiofrequency closure, 10 (35%) underwent open operation, and the remaining 19 (65%) patients underwent laparoscopic operation. RESULTS: Fistula occurred in 12 of 33 (36%) patients with traditional stump closure compared to 3 of 29 (10%) patients with radiofrequency closure (p<0.02). Operative time (307 vs. 231 min [p<0.002]) and blood loss (364-200 mL [p<0.02]) were decreased in the radiofrequency closure group. Length of stay decreased from 7.8 to 6.6 days; however, this was not statistically significant. CONCLUSIONS: The use of radiofrequency dissector in distal pancreatectomy is effective with low rates of fistula formation. Radiofrequency closure should be studied further in prospective trials.

Analysis of embryonic stem cell-derived osteogenic cultures.

The process of bone formation can be approximated in vitro in the form of a mineralized nodule. Osteoprogenitors and mesenchymal stem cells, the immediate precursors to the osteoprogenitor, when placed into culture proliferate and differentiate into osteoblasts. These osteoblasts secrete and mineralize a matrix during a period of 3-4 wk. The differentiation potential of embryonic stem cells (ESCs) suggests that ESCs should also have the ability to form bone nodules in vitro. ESCs were allowed to form embryoid bodies, which were disrupted and plated at concentrations as low as 25 cells/cm2. By 7 d postplating, a significant percentage of the colonies were morphologically characteristic of other types of osteogenic cultures. By 3 wk in culture, these colonies go on to form layered nodules. In a typical experiment, approx 60% of the colonies contain mineralized nodules, as revealed by staining of fixed cultures. Quantitative reverse transcriptase polymerase chain reaction analysis for genes characteristic of the osteoblast lineage has been used to confirm the presence of mature osteoblasts. Differentiation of ESCs into the osteoblast lineage will be a valuable tool for addressing pertinent questions about the proliferation, differentiation, survival, and intercellular communication between cells of the bone lineage in vitro.

Osteogenic nodule formation from single embryonic stem cell-derived progenitors.

The process of bone formation can be approximated in vitro in the form of a mineralized nodule. Osteoprogenitors and mesenchymal stem cells (MSCs), the immediate precursors of the osteoprogenitor, proliferate and differentiate into osteoblasts when placed into culture. These osteoblasts secrete and mineralize a matrix during a period of 3-4 weeks. The differentiation potential of embryonic stem (ES) cells suggests that ES cells should also have the ability to form osteogenic nodules in vitro. ES cells were allowed to form embryoid bodies (EBs) and were cultured in suspension for 2 days; EBs were disrupted and plated as single cells at concentrations as low as 25 cells/cm(2). We provide five lines of evidence for osteogenesis in these ES cell-derived cultures: (1) cell and colony morphology as revealed by phase-contrast microscopy, (2) mineralization of extracellular matrix as revealed by von Kossa staining, (3) quantitative real-time PCR (QRT-PCR) analysis of cDNA from entire plates and individual colonies revealing expression of genes characteristic of, and specific for, osteoblasts, (4) confocal microscopy of nodules from osteocalcin-green fluorescent protein (GFP) ES cell lines demonstrating the appropriate stage and position of osteoblasts expressing the reporter, and (5) immunostaining of nodules with a type I collagen antibody. Our method of initiating osteogenesis from ES cell-derived cultures is the only described method that allows for the observation and manipulation of the commitment stage of mesengenesis from single embryonic progenitors.