Post-extubation dysphagia in pediatric trauma patients: a single-center case-series study.

We aimed to investigate whether ventilator support time influences the occurrence of dysphagia in pediatric trauma patients. This case-series study was conducted in a single pediatric emergency and critical care center from April 2012 to March 2022. Trauma patients aged < 16 years who underwent tracheal intubation were divided into two groups based on the occurrence of dysphagia within 72 h after extubation, and their data were analyzed. Tracheal intubation was performed in 75 pediatric trauma patients, and 53 of them were included in the analysis. A total of 22 patients had post-extubation dysphagia and head trauma. The dysphagia group tended to have more severe head injuries (Abbreviated Injury Scale (AIS) 4 [4-5] vs. 4 [0-4]; p < 0.05), a longer ventilator support time (7 days [4-11] vs. 1 day [1-2.5]; p < 0.05), and a longer length of hospital stay (27 days [18.0-40.3] vs. 11 days [10.0-21.0]; p < 0.05). Severe head trauma and a long duration of tracheal intubation may be risk factors for dysphagia in pediatric trauma patients. Therefore, early recognition of these risk factors could assist in treatment planning for speech-language pathologist intervention and nutritional routes of administration.

Efficacy and safety of intravenous thiamylal in pediatric procedural sedation for magnetic resonance imaging.

OBJECTIVE: To evaluate the efficacy and safety of intravenous (i.v.) thiamylal in pediatric magnetic resonance imaging (MRI) sedation. METHODS: Infants and children from 1 month up to 8 years of age who underwent MRI in our hospital between April 2017 and March 2019 were included in this prospective observational study. Initial dose of 2 mg/kg thiamylal was given intravenously; however, additional doses were administered as needed. MRI was performed after adequate sedation was achieved. The primary endpoint was the success rate of MRI, while secondary endpoints were adverse events related to sedation, time to sedate, recovery time, and the dose of thiamylal. RESULTS: A total of 118 patients were included in the analysis with median age and weight of 31.5 months (14.0-56.8 months) and 12.6 kg (9.5-15.7 kg), respectively. The success rate of MRI was 96.6% (114/118), and the median dose of thiamylal per body weight was 3.6 (2.8-4.0) mg/kg. The median time from the first dose of thiamylal to MRI was 7 min (4-10 min) and that from the end of MRI scanning to the confirmation of emergence was 8 min (5-25 min). Adverse events encountered included respiratory arrests (n = 3) and reduction in oxygen saturation (SpO2; n = 9). There were no significant differences in the age, dose of thiamylal, sex, body weight, the American Society of Anesthesiologists physical status, and neurological abnormalities between the groups with and without respiratory complications. CONCLUSION: This study demonstrated an adequate efficacy and safety of i.v. thiamylal, with rapid sedation and patient recovery.

Preserved liver-specific functions of hepatocytes in 3D co-culture with endothelial cell sheets.

Hepatocyte-based tissue engineering is an attractive method that is being developed to treat liver diseases. However, this method is limited by the relatively short lifespan of cultured hepatocytes to maintain their normal function. For this reason, the present study was designed to develop a cell sheet-based hepatocyte co-culture system that enables cultured hepatocytes to preserve their functions for a longer period of time. To achieve this goal, a monolayer cell sheet composed of endothelial cells (EC) was placed on top of a monolayer of hepatocytes (Hep). In this hybrid cell sheet format, histological examination revealed that bile canaliculi networks were formed and well developed among the hepatocytes in the layered Hep-EC sheet group. The albumin secretion level was highly preserved at least for 28 days in the hybrid Hep-EC sheet, whereas the monolayer of hepatocytes exhibited a markedly reduced time course of secretion. The expression levels of hepatocyte-specific genes including albumin, hepatocyte nucleus factor 4 (HNF 4), multidrug resistance-associated protein 2 (MRP 2), and claudin-3 were significantly higher in the Hep-EC sheet compared to the Hep sheet alone after 14-days in culture. In all, this culture system provides a valuable technology to prolong hepatocyte functionality and enable more efficient development of liver tissue engineering approaches to create liver-targeted regenerative therapies.

Ectopic transplantation of hepatocyte sheets fabricated with temperature-responsive culture dishes.

AIM: Hepatocyte transplantation to host livers by single cell suspension injection from the portal vein has been clinically successful in cases where the host liver architecture is intact. However, further investigation is still needed to achieve regeneration of the liver architecture when the host liver is destroyed, since single cell suspension injection often results in the formation of small hepatocyte colonies or islands. We show a hepatocyte transplantation strategy to ectopic sites. METHODS: Primary hepatocytes isolated from green fluorescent protein (GFP)-transgenic rats were cultured on temperature-responsive culture dishes. After harvest as intact cell sheets, triple-layered cell sheets were transplanted over the superficial caudal epigastric artery and vein of athymic rats which had operation of 70% partial hepatectomy. RESULTS: The transplanted hepatocytes were integrated to host tissue with a laminar cell arrangement at transplanted sites within one week after surgery. But the transplanted hepatocytes were hardly detected four weeks after transplantation, when the partially hepatectomized host liver was completely regenerated. GFP-positive bile duct-like tubes and functional blood vessels were observed. CONCLUSION: These results imply the usefulness of hepatocyte sheets in ectopic transplantation, as well as the need of trophic factors for hepatocyte survival.

Microfluidic devices for size-dependent separation of liver cells.

Liver is composed of various kinds of cells, including hepatic parenchymal cells (hepatocytes) and nonparenchymal cells, and separation of these cells is essential for cellular therapies and pharmacological and metabolic studies. Here, we present microfluidic devices for purely hydrodynamic and size-dependent separation of liver cells, which utilize hydrodynamic filtration. By continuously introducing cell suspension into a microchannel with multiple side-branch channels, cells smaller than a specific size are removed from the mainstream, while large cells are focused onto a sidewall in the microchannel and then separated into two or three groups. Two types of PDMS-glass hybrid microdevices were fabricated, and rat liver cells were successfully separated. Also, cell size, morphology, viability and several cell functions were analyzed, and the separation performances of the microfluidic devices were compared to that of a conventional centrifugal technique. The results showed that the presented microfluidic devices are low-cost and suitable for clinical use, and capable of highly functional separation with relatively high-speed processing.