Digital revascularization and replantation using the wide-awake hand surgery technique.

The use of local anaesthesia and adrenaline for hand surgery is gaining popularity; however, where vascularity is impaired, wide-awake surgery is considered a contraindication. We present our case series of five digital devascularizations and eight amputations that underwent surgery using the 'wide-awake' anaesthetic technique. A temporary digital tourniquet (< 20 min) was used in three cases to identify structures quickly. The anastomoses were performed under local anaesthesia without a tourniquet. All cases had successful re-establishment of blood flow with good perfusion to the digital tips; no cases were re-explored because of vascular crisis. Four cases had minor superficial soft tissue necrosis that healed secondarily. We conclude that digital revascularization and replantation can be performed under local anaesthesia with use of adrenaline and without detriment to the traumatized digit provided careful patient selection and adequate operator experience are available. LEVEL OF EVIDENCE: IV.

Management of infraclavicular (Chuang Level IV) brachial plexus injuries: A single surgeon experience with 75 cases.

UNLABELLED: Infraclavicular brachial plexus injuries (Level IV in Chuang's classification) have special characteristics, including high incidences of associated scapular fractures, glenohumeral dislocations, and vascular injuries. In addition, there are specific difficulties in surgical dissection and nerve repairs, especially if surgery is delayed (>3 months). A total of 153 patients with Level IV brachial plexus injuries underwent surgery between 1987 and 2008 with 75 patients (average age 29 years) available for a minimum of 4 years follow-up. Accompanying fractures/dislocations were suffered by 48 (64%) patients, and 17 (23%) had associated vascular injuries. The most common nerves to be injured were the axillary and musculocutaneous nerves. Nerve grafts to the axillary, musculocutaneous, and radial nerves achieved impressive results, but less reliable outcomes were achieved with the median and ulnar nerves. Decompression and/or external neurolysis were also beneficial for nerve recovery. Some surgical tips are presented, and the use of the C-loop vascularized ulnar nerve graft and functioning muscle transfers are discussed. LEVEL OF EVIDENCE: IV.

Transplantation of autologous endothelial progenitor cells in porous PLGA scaffolds create a microenvironment for the regeneration of hyaline cartilage in rabbits.

OBJECTIVE: Repairing articular cartilage is clinically challenging. We investigated a simple, effective and clinically feasible cell-based therapeutic approach using a poly(lactide-co-glycolide) (PLGA) scaffold seeded with autologous endothelial progenitor cells (EPC) to repair a full-thickness osteochondral defect in rabbits using a one-step surgery. METHODS: EPC obtained by purifying a small amount of peripheral blood from rabbits were seeded into a highly porous, biocompatible PLGA scaffold, namely, EPC-PLGA, and implanted into the osteochondral defect in the medial femoral condyle. Twenty two rabbits were randomized into one of three groups: the empty defect group (ED), the PLGA-only group or the EPC-PLGA group. The defect sites were evaluated 4 and 12 weeks after implantation. RESULTS: At the end of testing, only the EPC-PLGA group showed the development of new cartilage tissue with a smooth, transparent and integrated articular surface. Moreover, histological analysis showed obvious differences in cartilage regeneration. At week 4, the EPC-PLGA group showed considerably higher TGF-ß2 and TGF-ß3 expression, a greater amount of synthesized glycosaminoglycan (GAG) content, and a higher degree of osteochondral angiogenesis in repaired tissues. At week 12, the EPC-PLGA group showed enhanced hyaline cartilage regeneration with a normal columnar chondrocyte arrangement, higher SOX9 expression, and greater GAG and collagen type II (COLII) content. Moreover, the EPC-PLGA group showed organized osteochondral integration, the formation of vessel-rich tubercular bone and significantly higher bone volume per tissue volume and trabecular thickness (Tb.Th). CONCLUSION: The present EPC-PLGA cell delivery system generates a suitable in situ microenvironment for osteochondral regeneration without the supplement of exogenous growth factors.

SCORTEN and impaired renal function related to mortality of toxic epidermal necrolysis syndrome patients in the Asian population.

BACKGROUND: Toxic epidermal necrolysis syndrome (TEN) is a rare, life-threatening, drug-related skin reaction with a high mortality rate. To date, only a few studies with insufficient sample sizes have been conducted to analyse SCORTEN in Asian populations with TEN. OBJECTIVE: To analyse SCORTEN and other related factors that affect TEN patients in Taiwan. METHODS: A retrospective review of medical records of 101 patients with TEN from 1992 to 2009. RESULTS: There were 62 cases of adverse reactions to a single medication and 39 cases of idiopathic reaction, from multiple medications, or infectious pathogens, of 101 TEN patients. Of the seven individual SCORTEN parameters, only associate malignancy, detached or compromised body surface area >10%, serum urea and bicarbonate were statistically significant in the multivariate analysis. Factors such as 1.5 times baseline serum creatinine levels, urine output of less than 0.5 mL/kg for 6 h and acute renal failure were connected with subsequent mortality. CONCLUSION: The SCORTEN score is effective in predicting the outcome in Taiwanese TEN patients. A number of factors are predictors of mortality. In our study, we determine renal insufficiency and failure to be a marker for predicting a poor outcome.

Nitrous oxide produces a biphasic effect on opiate-induced muscle rigidity in the rat.

Muscle rigidity is a side effect of potent opiate agonists like alfentanil. Older clinical studies suggested that nitrous oxide (N2O) augments opiate rigidity, but this has never been rigorously examined in an animal model. Sixty-two Wistar rats were placed in a Plexiglas box through which fresh gas flowed at 4 l/min. Muscle rigidity was assessed using gastrocnemius electromyographic (EMG) activity. Rats were exposed to either 60% N2O in O2 or 100% O2, EMG was measured for 10 min, alfentanil (0, 50, 175, or 350 micrograms/kg) was administered intravenously, and data were collected for 45 min. Alfentanil produced a dose-dependent increase in EMG activity in both O2 and N2O groups (p < 0.001). At 1 min postalfentanil, N2O caused significantly more rigidity than 100% O2 (p < 0.001). However, beginning at 5 min, N2O attenuated both the magnitude and the duration of rigidity. Study of a separate group of animals breathing 30% O2 demonstrated that N2O's attenuating effect on alfentanil rigidity was not due to reduced inspired oxygen concentration. These results are described by a theoretical model of the pharmacodynamic interactions of alfentanil and nitrous oxide.