自体腹膜管道替代血管在冠状动脉搭桥手术中的实验应用

目的 采用实验犬的腹膜片制作腹膜管道替代冠状动脉搭桥手术中的传统移植血管,希望为冠状动脉搭桥提供一种理想的血管替代物.方法 随机选用杂种成年犬10头,雌雄不限,麻醉后气管插管行机控呼吸.所有犬经旁正中切口达腹直肌鞘后层取腹膜片,制成腹膜管道在非体外循环下行主动脉与右冠状动脉主干搭桥.采用电磁血流量计测量搭桥前后腹膜管道的血流通畅度.术毕记录实验犬的早期存活比例,饲养至实验结束处死动物,光镜下观察HE染色腹膜管道的病理变化.结果 实验犬的早期死亡比例为10%(1/10),腹膜管道的血流通畅,冠状动脉搭桥手术前后实验犬右冠状动脉的血流量分别为(126±13)、(117±14)ml/min,差异无统计学意义(P>0.05).腹膜管道的组织学形态改变良好,光镜下,未见腹膜管道瘤样扩张,无明显纤维疤痕形成,腹膜管道弹力纤维结构完好,无断裂,腹膜管道与血管吻合口附近有血管内皮细胞衍生.结论 在非体外循环下采用腹膜管道替代传统的移植血管行冠状动脉搭桥创伤小,实验犬存活比例高,冠状动脉血供效果令人满意,有希望成为理想的血管移植替代物.     

Urinary Diversion Following Cystectomy

Urinary diversion is an essential component of the surgical procedure after cystectomy. Replacement with an orthotopic ileal neobladder should be the first choice if external urethral sphincter sparing surgery is possible, offering good long-term function, quality of life and patient's acceptance with few complications.The possible use of a variety of alternative intestinal segments widen the horizon of the reconstructive surgeon, allowing him or her to be prepared for unusual cases.Contraindications for orthotopic neobladder reconstruction include tumour location, reduced renal, liver, intestinal function, intellectual ability and physical handicaps.It is therefore important to custom tailor the appropriate mode of diversion for individual patients with a variety of options available, including ureterocutaneous stomas, intestinal conduits and continent catheterizable reservoirs and orthotopic neobladders. All these techniques require detailed knowledge of the possible metabolic problems encountered by using gastrointestinal segments and how they react in contact with urine. Modern surgical techniques such as nerve sparing surgery have the ability to preserve postoperative continence with voluntarily micturition as well as sexual function. In addition, preliminary experimental data hold great promise that the “off shelf” bladder substitute may become a technique of choice in the future, avoiding common problems encountered using current technqiues.     

Perimount® Bovine Pericardial Valve to Restore Pulmonary Valve Competence Late after Right Ventricular Outflow Tract Repair

Objective. No ideal option exists for restoring pulmonary valve competence late after repair of the congenitally abnormal right ventricular outflow tract (RVOT). This has driven a continued search for new alternatives. Texas Children’s Hospital has recently used the Carpentier‐Edwards Perimount RSR Pericardial Aortic Prosthesis (Edwards Lifesciences, Irvine, Calif, USA) for this indication and reports the initial experience. Design. Retrospective chart review. Setting. Academically affiliated tertiary‐care pediatric hospital. Patients. Twenty‐six patients who underwent pulmonary valve replacement with the Perimount^® valve late after RVOT reconstruction between June 2002 and November 2005. Interventions. No prospective interventions. Outcomes Measures. Hospital morbidity and mortality. Valve function assessed by follow‐up visits and echocardiograms. Results. Mean age and weight of the patients were 20.3 ± 9.8 years (range 7.0–45.1 years) and 56.2 ± 18.1 kg (range 35.8–109 kg). Twenty‐two patients (85%) had severe pulmonary insufficiency (PI), 23 (89%) had symptomatic right heart failure, and 14 (54%) had moderate to severe right ventricular dysfunction. Average prosthetic valve size was 23 mm (range 19–27 mm). Twenty‐one (88%) patients were extubated within 24 hours. There was no hospital mortality. Median length of stay for all patients from day of surgery was 6 days (range 3–56 days). Median length of last echocardiography follow‐up was 12.4 months (range 0.1–37.6 months). At that time, 16 of the 26 (62%) patients had improved right ventricular function, no patient demonstrated significant RVOT obstruction, and 24 patients (92%) have no PI or mild PI. Freedom from death, reintervention, or reoperation on the pulmonary valve is 100% at 2.5 years. Conclusion. Initial results with the Perimount^® bovine pericardial tissue prosthesis for pulmonary valve replacement are encouraging. Further follow‐up is required to define long‐term function and durability.     

Diagnosing infection of extracardiac conduit in children

Summary Between August 1985 and July 1992, at our center, 142 Japanese children had an extracardiac conduit operation to reconstruct the right ventricular outflow tract. The study group consisted of 22 of these 142 children who had a persistent fever and whose serum was positive for acute-phase reactants after the operation. We present the diagnostic findings for 10 children with infection of an extracardiac conduit that had been placed to restore the continuity of the right ventricle-pulmonary artery. They were part of the group of 22 children who were followed over the past 7 years with blood cultures, echocardiography, and⁶⁷Ga imaging. All 10 developed a persistent fever and were seropositive for acute-phase reactants. Conduit infection was diagnosed in only 2 patients by the detection of vegetation on echocardiography and was diagnosed in 9 of the 10 patients by an abnormal⁶⁷Ga uptake in the area of the artificial vessels used to reconstruct the pulmonary artery. The present study compared the use of blood cultures, echocardiography, and⁶⁷Ga imaging in diagnosing an infection of the extracardiac conduit. The sensitivity of blood cultures in diagnosing an extracardiac conduit infection was 70% (7/10), and the specificity was 92% (1/12).⁶⁷Ga imaging showed a higher sensitivity than echocardiography in diagnosing infection of an extracardiac conduit.     

Muscle and nerve biopsies: Techniques for the neurologist and neurosurgeon

Objective

Muscle and nerve biopsies are commonly performed procedures for the diagnosis of neuromuscular disorders. Neurologists and neurosurgeons are often consulted to perform these procedures in clinical practice. We provide guidelines in the performance of muscle and nerve biopsies.

Methods

We describe the technique for performance of muscle and nerve biopsy, and review the relevant literature.

Results

The quadriceps muscle is the most typical biopsy site for most myopathies, whereas the sural nerve is the most common nerve biopsy site for most peripheral neuropathies. Other sites may be utilized depending upon the pattern of symptoms or the differential diagnosis. Motor nerves may be sampled in the setting of motor neuron disease, for example. We advocate the use of conduit repair to allow for sensory or motor recovery to occur following nerve biopsy.

Conclusion

The muscle biopsy and nerve biopsy may be performed with high yield, low morbidity, and rare complications.     

Comparative study between Air-Q and Intubating Laryngeal Mask Airway when used as conduit for fiber-optic

This study compared Air-Q and Intubating LMA when used as a conduit for endotracheal intubation.MethodsOne hundred patients scheduled for surgical operations under general anesthesia were randomly allocated into two equal groups (n = 50). Group I: Air-Q and group II: Intubating Laryngeal Mask Airway (ILMA) in both groups intubation was done by Fiberoptic bronchoscope (FOB) through study device. After induction of anesthesia, patients were ventilated with Air-Q or ILMA. Then, endotracheal tube (ETT) was inserted through study device. Recorded measurements were as follows: number of attempts and duration of insertion of device, peak airway pressure and fiberoptic grading of laryngeal view. Also, we recorded number of attempts and duration of insertion of ETT and the incidence of blood stain on device and sore throat grading.ResultsDuration of insertion of Air-Q was 13.300 ± 3.471 s, whilst that of ILMA was 19.640 ± 4.737 s (p < 0.001). In group I, peak airway pressure was 26.400 ± 2.176 cmH₂O, whilst, in group II, it was 25.260 ± 1.468 cmH₂O (p < 0.01). Full view of vocal cords amounted to 78% and 26% of Groups I and II patients, respectively (p < 0.001). Time of insertion of ETT was 33.5 ± 6.795 s in group I, whilst in group II, it was 39.5 ± 6.566 s (p < 0.001). Blood stain was found on supraglottic device in 46% and 22% of cases in Groups I and II, respectively (p < 0.01).ConclusionAir-Q proved to be an excellent conduit for endotracheal intubation compared to the ILMA.     

Regenerative potential of silk conduits in repair of peripheral nerve injury in adult rats

Various attempts have been made to develop artificial conduits for nerve repair, but with limited success. We describe here conduits made from Bombyx mori regenerated silk protein, and containing luminal fibres of Spidrex^®, a silk-based biomaterial with properties similar to those of spider silk. Assessment in vitro demonstrated that Spidrex^® fibres support neurite outgrowth. For evaluation in vivo, silk conduits 10 mm in length and containing 0, 100, 200 or 300 luminal Spidrex^® fibres, were implanted to bridge an 8 mm gap in the rat sciatic nerve. At 4 weeks, conduits containing 200 luminal Spidrex^® fibres (PN200) supported 62% and 59% as much axon growth as autologous nerve graft controls at mid-conduit and distal nerve respectively. Furthermore, Spidrex^® conduits displayed similar Schwann cell support and macrophage response to controls. At 12 weeks, animals implanted with PN200 conduits showed similar numbers of myelinated axons (81%) to controls, similar gastrocnemius muscle innervation, and similar hindpaw stance assessed by Catwalk footprint analysis. Plantar skin innervation was 73% of that of controls. PN200 Spidrex^® conduits were also effective at bridging longer (11 and 13 mm) gaps. Our results show that Spidrex^® conduits promote excellent axonal regeneration and function recovery, and may have potential for clinical application.     

Jugular venous valved conduit (Contegra) matches allograft performance in infant truncus arteriosus repair

Objective: Limited availability and durability of allograft conduits require that alternatives be considered. We compared bovine jugular venous valved (JVV) and allograft conduit performance in 107 infants who survived truncus arteriosus repair. Methods: Children were prospectively recruited between 2003 and 2007 from 17 institutions. The median z-score for JVV (n = 27, all 12 mm) was +2.1 (range +1.2 to +3.2) and allograft (n = 80, 9–15 mm) was +1.7 (range −0.4 to +3.6). Propensity-adjusted comparison of conduit survival was undertaken using parametric risk-hazard analysis and competing risks techniques. All available echocardiograms (n = 745) were used to model deterioration of conduit function in regression equations adjusted for repeated measures. Results: Overall conduit survival was 64 ± 9% at 3 years. Conduit replacement was for conduit stenosis (n = 16) and/or pulmonary artery stenosis (n = 18) or regurgitation (n = 1). The propensity-adjusted 3-year freedom from replacement for in-conduit stenosis was 96 ± 4% for JVV and 69 ± 8% for allograft (p = 0.05). The risk of intervention or replacement for branch pulmonary artery stenosis was similar for JVV and allograft. Smaller conduit z-score predicted poor conduit performance (p < 0.01) with best outcome between +1 and +3. Although JVV conduits were a uniform diameter, their z-score more consistently matched this ideal. JVV exhibited a non-significant trend towards slower progression of conduit regurgitation and peak right ventricular outflow tract (RVOT) gradient. In addition, catheter intervention was more successful at slowing subsequent gradient progression in children with JVV versus those with allograft (p < 0.01). Conclusions: JVV does match allograft performance and may be advantageous. It is an appropriate first choice for repair of truncus arteriosus, and perhaps other small infants requiring RVOT reconstruction.     

Renal function in the setting of urinary diversion

Incorporating bowel into the urinary tract sets the stage for a potentially dangerous situation for the upper part of this tract. Obstruction, reflux and chronic bacteriuria may develop, all of which can all be detrimental. Most reports on renal function have used IVP and serum creatinine only, methods which are inadequate for proper assessment. Long-term follow-up of patients with ileal conduit diversion reveals a high incidence of morphological and/or functional damage to the kidneys. Refluxing techniques for implanting the ureters have usually been employed. In patients with continent cutaneous diversion or orthotopic bladder substitution, some recent publications have shown rather well preserved glomerular filtration rates. Traditionally, antirefluxing ureteric implantation has been used in these patients. There is presently a trend towards refluxing anastomosis in this setting, providing a low pressure pouch has been constructed. However, pressure can be high in such pouches and bacteriuria is common. The consequences for the fate of the upper urinary tract is unknown and caution should be exercised in recommending such techniques. There is clearly a need for prospective randomized controlled studies on the issue of refluxing versus antirefluxing anastomosis in continent urinary reconstruction. Patients with continent or non-continent diversion should have lifelong follow-up with regard to the upper urinary tract.