Effect of perineurial window size on nerve regeneration, blood-nerve barrier integrity, and functional recovery

End-to-side neurorrhaphy is used clinically to reconstruct nerve injuries when the lack of a suitable proximal nerve stump precludes conventional approaches to microsurgical repair. In end-to-side neurorrhaphy, the distal stump of a transected nerve is sutured to the side of an intact nerve that serves as an axon donor. Prior studies suggest that this perineurial window is a prerequisite for effective nerve regeneration into the recipient nerve. However, the optimal size for this perineurial window remains uncertain. This study evaluated the effect of perineurial window size on collateral axonal sprouting, blood-nerve barrier architecture, and functional impairment of the donor nerve. One hundred twenty Lewis rats were randomized to 1 and 5 mm perineurial window groups and examined at serial time points. The 5 mm perineurial window group exhibited significantly greater fiber counts at the repair zone than the 1mm group within 4 weeks (p < 0.005). Marked breakdown of the blood-nerve barrier was present 2 week postoperatively and resolved by 4 weeks regardless of 1 versus 5 mm perineurial window size. Tibial function indices in both groups normalized between 4 and 6 weeks postoperatively. A large (5 mm) perineurial window induced greater collateral sprouting or regenerative response than a small (1 mm) perineurial window without increasing cross sectional nerve injury or delaying functional recovery.     

Superior mesenteric artery syndrome following correction of kyphosis in an adult

Superior mesenteric artery (SMA) syndrome is well described in the pediatric literature; however, to date, it has not been described in an adult individual undergoing correction of thoracic kyphosis. Medical history, physical findings, and the results of imaging studies were analyzed to describe the patient's onset of gastrointestinal obstruction following surgical correction of thoracic kyphosis. The postoperative course was marked by the onset of nausea and vomiting on postoperative day 24. The patient was admitted to the hospital, and the small bowel follow-through study showed blockage of the third portion of the duodenum at the level of the SMA. Oral intake was restricted, and total parenteral nutrition was instituted with complete resolution of her symptoms. At 1 year postoperatively, the patient was symptom-free. Although vascular compression of the duodenum with subsequent nausea and vomiting and electrolyte imbalance, caused by the relative lengthening of the spine, is most commonly associated with surgical correction of coronal plane deformities (ie, scoliosis), it may occur in patients undergoing correction of thoracic kyphosis as well. SMA syndrome is a well known potential complication in adolescents, and it should also be taken into consideration in adults undergoing deformity correction. Early institution of general medical measures of nasogastric suction, oral intake restriction, and intravenous alimentation can be successful.     

High dose rate brachytherapy in the management of lung transplant airway stenosis

BACKGROUND: Airway complications after lung transplantation remain a major cause of postoperative morbidity and mortality. Interventional bronchoscopic management continues to be the main modality in the management of these problems. METHODS: Four patients with airway stenoses after lung transplantation received high dose rate brachytherapy for management of recurrent stenosis. All 4 patients had been treated with various bronchoscopic interventions, including dilation and stenting, electrocautery ablation, and neodymium:yttrium-aluminum-garnet laser therapy. High dose rate endobronchial brachytherapy was subsequently used in all 4 patients for management of recurrent airway obstruction. The radiation dose for all 4 patients was 3 Gy at a distance of 1 cm from the center of the catheter. RESULTS: All four patients have had routine follow-up after endobronchial brachytherapy treatments. Of the 4 patients, 2 treated with this modality showed a significant response to therapy in that the bronchus remained free of obstruction after treatment; 1 patient had partial improvement, and 1 patient failed to show significant improvement and expired from the sequelae of persistent airway obstruction. CONCLUSIONS: Endobronchial brachytherapy can be an effective modality for managing recurrent stenoses caused by hyperplastic granulation tissue at the bronchial anastomosis. The optimal timing and ideal candidate for intraluminal radiation therapy for this problem remains a challenge and warrants further investigation.     

Incidence of systemic fungal infection and related mortality following severe burns

Advancements in burn care therapy have extended survival of seriously burned patients, exposing burn patients to increased risk of infectious complications, notably fungal infections. We performed a 12-year review of autopsied patients with severe burns for the presence of fungal infection at the US Army Institute of Surgical Research Burn Center between February 1991 and November 2003. The primary goal was to identify the relationship between fungal element noted in autopsy and mortality, and to determine contributing factors that increase a patient's susceptibility to fungal infection. A total of 228 deaths (6.1%) resulted from the 3751 admissions of which 97 underwent autopsy. Fungal elements were identified on histopathology in 44% (43 of 97) of autopsied patients with an attributable mortality of 33% (14 of 43). Aspergillus and Candida were the most frequently recovered fungi, but Aspergillus was recovered in 13 of the 14 cases with fungus identified as an attributable cause of death. The most common sites of infections with attributable mortality were wounds (86%) and the pulmonary system (14%). Total body surface area (TBSA) burn and length of stay (survival after burn) were identified as contributing factors for the incidence of fungal element in autopsy on ROC curve analysis. More severely injured patients with greater %TBSA burn injury and full-thickness burns require a longer recovery period resulting in a longer hospital stay. The propensity for fungal infection increases the longer the wound is present. Therefore, the development of products to close the wound more rapidly, improvement in topical antifungal therapy with mold activity for treating wounds, and implementation of appropriate systemic antifungal therapy may improve outcome for severely injured burn victims susceptible to fungal infections.