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Objective:To observe the effect of adipose tissue decellularized matrix hydrogel (DAT-gel) on the repair of sciatic nerve defect in rats.Methods:From April, 2019 to April, 2020, aseptic granular adipose tissue was collected from healthy adult women who underwent thigh or abdominal liposuction in the Department of Plastic Surgery, the First Medical Centre of the PLA General Hospital. Decellularisation and enzymatic digestion of adipose tissue were performed to prepare DAT-gel. Scanning electron microscope (SEM) was used to observe the ultrastructure of the hydrogel, and rheology was employed to test the gel dynamics and viscoelasticity of the hydrogel. A rat model of sciatic nerve defect was established and randomly divided into 3 groups: simple chitin catheter group (Chitin group), DAT-gel plus chitin catheter group (DAT-gel group) and autologous nerve reverse connection group (Autograft group) with 10 rats in each group. At the 12th week after surgery, the general view, function and morphology of the regenerated nerve were observed to evaluate the repairing status of the injured nerve. One-way analysis of variance (one-way ANOVA) was used for data analysis. If the difference between the groups was statistically significant, the Turkey method was further used for pairwise comparison. P<0.05 was considered as statistically significant. Results:The results of SEM showed that the DAT-gel had a three-dimensional structure in porous fibre network. The results of rheological test results showed that the complex viscosity of the hydrogel at 4 ℃ and 37 ℃ were 148.91 mPa·s and 801.29 mPa·s, respectively. DAT-gel underwent a sol-gel phase transition when the temperature had been increased. The results showed that DAT-gel had a good temperature-sensitive effect, and its critical point of sol-gel phase transition was similar to the internal temperature of rat. The results of animal experiments showed that the morphology and function of the regenerated nerve in the DAT-gel group were superior to Chitin group at 12 weeks after surgery, according to macroscopic view of the regenerated nerve, electrophysiology of the nerve, the morphology of the new axon and the target muscle, etc.. There was statistically significant between groups ( P<0.05). Conclusion:DAT-gel can significantly promote a repair of sciatic nerve defects in rats.
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Gradual distraction with an external fixator is a widely used treatment for severe postburn ankle contracture (SPAC). However, application of external fixators is complex, and conventional two-dimensional (2D) imaging-based surgical planning is not particularly helpful due to a lack of spatial geometry. The purpose of this study was to evaluate the surgical planning process for this procedure with patient-specific three-dimension-printed models (3DPMs). In this study, patients coming from two centers were divided into two cohorts (3DPM group vs. control group) depending on whether a 3DPM was used for preoperative surgical planning. Operation duration, improvement in metatarsal-tibial angle (MTA), range of motion (ROM), the American Orthopedic Foot and Ankle Society (AOFAS) scores, complications, and patient-reported satisfaction were compared between two groups. The 3DPM group had significantly shorter operation duration than the control group ((2.0±0.3) h vs. (3.2±0.3) h,
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BACKGROUND:In 2001, Zuk et al found adipose-derived stem cels (ASCs) from the aspirate of liposuction for the first time, which launched a new era of stem cel research. In recent years, stem cels have been proved to widely exist in many tissues and organs. ASCs are always in the spotlight of plastic and reconstructive surgery, tissue engineering and regenerative medicine because of extensive sources and simple isolation. OBJECTIVE: To review the fat tissue harvesting and ASCs isolation, purification, expansion, and cryopreservation, to discuss the main factors which influence the yield, proliferation capacity and differentiation potential of ASCs, and to predict the future research interests based on current issues. METHODS:On September 10th, 2015, relevant articles were searched in PubMed using the folowing format: (adipose stem cels[Title]) OR (adipose-derived stem cels[Title]) OR (adipose-derived mesenchymal stem cels[Title]) and in SinoMed using the folowing format in Chinese: (“adipose-derived stem cels” [Title])or(“adipose-derived mesenchymal stem cels”[Title]). Finaly, 81 representative articles were included according to their titles and abstracts. In this review, we also introduced relevant experience about the aforementioned procedures from the Department of Plastic Surgery and Tissue Regeneration and Molecular Cel Engineering Lab of University of Texas, MD Anderson Cancer Center, USA. RESULTS AND CONCLUSION:The widely dispersed fat tissues potentialy provide abundant stem cels for tissue engineering and regenerative medicine. Liposuction is a mini-invasive approach for harvesting fat tissues. Colagenase digestion is the major method for ASCs isolation due to its simplicity and high yield in basic research. However, clinical fat transplantation without ASCs isolation or non-colagenase isolation of stromal vascular fraction or ASCs is preferred. The phenotype, proliferation and differentiation capacity of ASCs may be affected by several factors during the fat tissue harvesting and ASCs isolation. Therefore, a standard protocol for ASCs isolation is needed.
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Objective To compare efficacy, time consumed and complications among cricothyroid membrane puncture guided tracheostomy ( CMPGT ) , surgical tracheostomy ( ST ) , surgical cricothyroidotomy ( SC) , and percutaneous tracheostomy using Griggs'guide wire dilating forceps ( GWDF) for the establishment of airway in urgent need of medical attention.Methods Twenty miniature swine were randomly ( random number) divided into four groups.The procedures of CMPGT, ST, SC and GWDF were carried out when patients'SpO2 ( oxygen saturation of blood ) declined to 80% by suspension of oxygen supply after general anesthesia. Procedure performed time, ventilation resumed time, SpO2 and electrocardiograph ( ECG) and arterial blood gases ( ABG) analysis including SaO2 , PaO2 , PaCO2 , blood pH, and heart rate, blood pressure were recorded.Fiberoptic bronchoscope was used to assess any damage to the tracheal wall.Complications were noted and scored in a two-month follow-up period.Results Airways were successfully established in all swine.The times consumed for SC, GWDF, CMPGT, and ST were (86 ±12) s, (165 ±63) s, (174 ±34) s, and (519 ±128) s, respectively, however a shorter time for ventilation resumed was found in CMPGT procedure (23 ±4) s, P<0.01.ECG showed that SpO2 and T-wave decreased and Q-T shortened after oxygen suspension and recovered to normal level rapidly after ventilation.There were significant differences in ECG and ABG between pre-and post-operative periods ( P<0.05) in all groups.Minimal intra-operative bleeding was found in two swine of each group.In ST group, moderate intra-operative bleeding was encountered in three swine.Three pigs were suffered from hypotension owing to prolonged hypoxemia.There was minimal postoperative bleeding occurred in one swine, thus leading to stoma infection.In SC group, moderate intra-operative bleeding was noticed in one swine. One miniature swine had slight injury at laryngeal cartilage resulting in difficult decannulation happened in one swine.and moderate tracheal wall injury occurred in one swine of GWDF group.The complication scores of CMPGT, GWDF, SC and ST were 3, 5, 9, and 19, respectively.Conclusions A shorter time for ventilation resumed with fewer complications was found in the procedure of CMPGT than that in the other methods.This animal study suggested that CMPGT was a time-saving and secure technique for emergency surgical airway establishment which has been practiced in human being as well.Key words:Surgical airway establishment, Cricothyroidotomy, Tracheostomy, Percutaneous dilational tracheostomy.
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Tracheostomy is to establish an artificial airway by making an opening at anterior tracheal wall. Due to the blossom of mechanical ventilation and intensive care unit after 1950s, tracheostomy is the most favorable surgical method to access airway at present. In addition to traditional surgical tracheostomy, percutaneous dilational tracheostomy have gained increasing popularity and become an alternative procedure because of its merits such as easier manipulation, shorter operative duration and less complications. This review summarized tracheostomy from definition, history and current status, anatomy and physiology, indications, contraindications, timing, complications and management. We also elaborate our understanding of current contraercy and give some suggestions based on our clinical experience.
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Humans , Intensive Care Units , Respiration, Artificial , Trachea , General Surgery , Tracheostomy , MethodsABSTRACT
<p><b>OBJECTIVE</b>To compare cricothyroid membrane puncture directed tracheostomy (CMPDT) with conventional surgical tracheostomy (ST) and cricothyroidotomy (CT) and to evaluate the feasibility, efficacy and safety of this novel technique.</p><p><b>METHODS</b>15 minipigs were divided randomly into 3 groups, 5 in each. After general anesthesia, CMPDT, ST and CT were performed respectively according to the established techniques when SPO₂reached 80% (T0). Procedure duration, ECG and arterial blood gas results were recorded. Complications were recorded and scored according to an established score scale by an observer blinded to the grouping.</p><p><b>RESULTS</b>Airway was successfully established in all animals (15/15). ECG monitor showed T-wave decreased and Q-T shortened after seasing of oxygen supply and both recovered rapidly to normal levels after reoxygenation. There were no significant differences between 3 groups in HR, BP, SPO2, SaO₂, PaO₂, PaCO₂and pH at pre-apnea, T0 or post-operation, but with significant intragroup variation in the parameters before and after operation. The time for CMPDT, ST and CT was (174 ± 34) s, (619 ± 128) s and (86 ± 12) s respectively. Three of 5 minipigs in ST group experienced hypotension due to longer time of hypoxia. 1 and one had minor bleeding and stoma infection after surgery. One of 5 animals in CT group had minor laryngeal cartilage injury leading to difficult decannulation, postoperative fiber bronchoscopy showed no subglottic stenosis. The complication scores were 13, 9, and 3 for ST, CT and CMPDT, respectively.</p><p><b>CONCLUSIONS</b>All 3 methods can provide with effective airway access with no significant differences in ventilation effect, however CMPDT has short recovery time for SpO2 and other vital signs with the lowest complication score. The animal experiment suggests that CMPDT is a fast, safe and effective surgical technique for emergency airway.</p>