Faisal M. Shaikh

The Long-Term Results of Pubovaginal Sling Surgery Using Acellular Cross-Linked Porcine Dermis in the Treatment of Urodynamic Stress Incontinence

PURPOSE Acellular cross-linked porcine dermis is a potential substitute for rectus fascia as a sling material with the advantage of decreased morbidity. However, the long-term efficacy is unknown. We compared the 3-year efficacy of PD vs autologous rectus fascia as a sling material for pubovaginal sling surgery in the treatment of urodynamic stress incontinence. MATERIALS AND METHODS Between July 2000 and December 2001 a total of 101 consecutive, nonrandomized patients with USI underwent a PD (51) or RF (50) sling procedure. Patients were assessed at 6 weeks, and at 3, 6 and 12 months postoperatively. Urodynamic study was repeated in cases of treatment failure. A detailed survey questionnaire was mailed to all patients at least 36 months after surgery and all responders were then retested by telephone interview by a blinded assessor. The primary outcome measure was patient perceived success rate (cured or improved) at least 36 months after PVS. Secondary outcome measures were patient satisfaction 36 months after surgery, durability of success with time and reoperation rate. RESULTS Complete data were available on 94 patients (48 treated with PD and 46 treated with RF sling). The groups were well matched for age, leak point pressure, prior incontinence surgery and urge symptoms. Pubovaginal sling was successful (cured or improved) in 37 (80.4%) patients treated with RF but in only 26 (54%) patients treated with PD 36 months after surgery (Fishers exact test p = 0.009; 95% CI 8.03, 44.4). Treatment failure occurred by 9 months after RF and by 24 months after PD sling procedure. Repeat urodynamic study showed USI to be the cause of treatment failure in 18 (37.5%) of 20 patients treated with PD but in only 3 (6.5%) of 8 patients treated with RF. CONCLUSIONS We have shown that use of the PD sling, although reducing early morbidity, results in a significantly inferior long-term cure rate in comparison to the RF sling. Therefore, acellular cross-linked porcine dermis should not be used as a substitute for rectus fascia.

Efficacy of Wedge Resection With Phenolization in the Treatment of Ingrowing Toenails

BACKGROUND Ingrowing toenail is a common condition treated by general surgeons. Our aim was to analyze the effectiveness of wedge resection with phenolization in the surgical treatment of ingrowing toenails. METHODS We retrospectively audited 100 patients who underwent wedge resection with phenolization for the treatment of ingrowing toenail between January 2000 and June 2004 by a single surgeon. We reviewed all charts and attempted to contact all patients for a telephone interview to assess patient satisfaction. Outcome measures were: 1) recurrence rate, 2) duration of analgesic use, 3) postoperative complications including wound infection, 4) time to return to normal activities, and 5) satisfaction with the procedure. RESULTS A total of 168 wedge resection with phenolization procedures were performed on 100 patients. There was only one recurrence (0.6%). Two patients (2%) had wound infection and were treated with oral antibiotics. The average time for a single wedge resection with phenolization procedure was 7.3 minutes. The mean time to return to normal activities was 2.1 weeks. The patient response rate for the telephone interview was 60%. Most respondents (93.3%) were satisfied with the overall outcome. CONCLUSIONS Wedge resection with phenolization is a very effective mode of therapy in the surgical treatment of ingrowing toenail, with a very low recurrence rate and minimal postoperative morbidity. Wedge resection with phenolization should be considered as a good alternative technique in the treatment of ingrowing toenail.

New Pulsatile Hydrostatic Pressure Bioreactor for Vascular Tissue‐engineered Constructs

Mechanical conditioning represents a potential means to enhance the biochemical and biomechanical properties of tissue-engineered cell constructs. Bioreactors that can simulate physiologic conditions can play an important role in the preparation of tissue-engineered constructs. Although various forms of bioreactor systems are currently available, these have certain limitations, particularly when these are used for the creation of vascular constructs. The aim of the present report is to describe and validate a novel pressure bioreactor system for the creation of vascular tissue. Here, we present and discuss the design concepts, criteria, as well as the development of a novel pressure bioreactor. The system is compact and easily housed in an incubator to maintain sterility of the construct. Moreover, the proposed bioreactor, in addition to mimicking in vivo pressure conditions, is flexible, allowing different types of constructs to be exposed to various physiologic pressure conditions. The core bioreactor elements can be easily sterilized and have good ergonomic assembly characteristics. This system is a fundamental tool, which may enable us to make further advances in bioreactor technology and tissue engineering. The novel system allows for the application of pressure that may facilitate the growth and development of constructs needed to produce a tissue-engineered vascular graft.

The Influence of a Eutectic Mixture of Lidocaine and Prilocaine on Minor Surgical Procedures: A Randomized Controlled Double-Blind Trial

BACKGROUND A eutectic mixture of lidocaine and prilocaine (EMLA) has been shown to be effective in reducing pain from needle sticks, including those associated with blood sampling and intravenous insertion. OBJECTIVE To evaluate the effectiveness of EMLA cream applied before needle puncture for local anesthetic administration before minor surgical procedures in this double‐blind, randomized, controlled, parallel‐group study. MATERIALS AND METHODS Patients were randomly assigned to receive EMLA or placebo cream (Aqueous) applied under an occlusive dressing. After the procedure, patients were asked to rate the needle prick and procedure pain on a visual analog scale (0=no pain; 10=maximum pain). RESULTS A total of 94 minor surgical procedures (49 in EMLA and 45 in control) were performed. The mean needle‐stick pain score in the EMLA group was significantly lower than in the control group (2.7 vs. 5.7, p<.001, Mann‐Whitney U‐test). There was also significantly lower procedure pain in the EMLA group than in the control group (0.83 vs. 1.86, p=.009). There were no complications associated with the use of EMLA. CONCLUSION EMLA effectively reduces the preprocedural needle‐stick pain and procedural pain associated with minor surgical procedures.

Mobile surgical skills education unit: a new concept in surgical training.

Basic surgical skills are an integral part of surgical training. Simulation-based surgical training offers an opportunity both to trainees and trainers to learn and teach surgical skills outside the operating room in a nonpatient, nonstressed environment. However, widespread adoption of simulation technology especially in medical education is prohibited by its inherent higher cost, limited space, and interruptions to clinical duties. Mobile skills laboratory has been proposed as a means to address some of these limitations. A new program is designed by the Royal College of Surgeons in Ireland (RCSI), in an approach to teach its postgraduate basic surgical trainees the necessary surgical skills, by making the use of mobile innovative simulation technology in their own hospital settings. In this article, authors describe the program and students response to the mobile surgical skills being delivered in the region of their training hospitals and by their own regional consultant trainers.

Comparing the endothelialisation of extracellular matrix bioscaffolds with coated synthetic vascular graft materials

INTRODUCTION Existing synthetic vascular grafts have unacceptably high failure rates when replacing below knee arteries. In vitro endothelialisation is a technique, which has been shown to enhance the patency rates of below knee vascular grafts. Synthetic materials are however poor cellular substrates and must be combined with coatings to promote cellular growth and attachment. The most common coating clinically is fibrin-coated ePTFE. The aim of our study was to compare the endothelialisation of fibrin-coated ePTFE with novel extracellular matrix (ECM) biomaterials that we hypothesise will provide a superior substrate for cell growth. METHODS Human endothelial cells were cultured on ECM scaffolds and fibrin-coated ePTFE. Uncoated Dacron and ePTFE acted as controls. The cells were examined for viability, phenotype, adhesion and proliferation. Cell morphology was accessed using scanning electron microscopy. RESULTS Cells remained viable and produced von Willebrand factor on all substrates tested. ECM scaffolds and fibrin-modified ePTFE achieved statistically higher attachment efficiency when compared to both uncoated synthetic graft materials (p ≤ 0.001). At 90 min 80 ± 3.6% of cells had attached to the ECM scaffold compared to Dacron (30 ± 4.5%, n = 3) and ePTFE (33 ± 2.5%, n = 3). There was no difference in adhesion rates between ECM scaffolds and fibrin-coated ePTFE (p = 1.00). Endothelial cells proliferated fastest on ECM scaffolds when compared to all other materials tested (p < 0.001) and reached confluency on day seven. CONCLUSION ECM bioscaffolds offer an improved substrate for promoting rapid endothelialisation compared to fibrin-coated ePTFE by combining firm cellular anchorage and superior cell expansion.

Design and evaluation of a novel subatmospheric pressure bioreactor for the preconditioning of tissue-engineered vascular constructs

Purpose The pre-conditioning of tissue-engineered vascular scaffolds with mechanical stimuli is being recognised as an essential step in producing a functional vascular construct. In this study we design and evaluate a novel bioreactor, which exerts a mechanical strain on developing vascular scaffolds via subatmospheric pressure. Methods We design and construct a bioreactor, which exerts subatmospheric pressure via a vacuum assisted closure unit. Vascular scaffolds seeded with human umbilical endothelial cells were evaluated for structural integrity, microbial contamination, cellular viability, von Willebrand factor (VWF) production, cell proliferation and morphology under a range of subatmospheric pressures (75-200mmHg). Results The bioreactor produced sustained subatmospheric pressures, which exerted a mechanical strain on the vascular scaffold. No microbial contamination was found during the study. The structural integrity of the vascular construct was maintained. There was no difference in cellular viability between control or subatmospheric pressure groups (p = 0.817). Cells continued to produce VWF under a range of subatmospheric pressures. Cells subjected to subatmospheric pressures of 125mmHg and 200mmHg exhibited higher levels of growth than cells in atmospheric pressure at 24 (p≤0.016) and 48 hour (p≤0.001). Negative pressure affected cellular morphology, which were more organised, elongated and expanded when exposed to subatmospheric pressure. Conclusions We have constructed and validated a novel subatmospheric bioreactor. The bioreactor maintained a continuous subatmospheric pressure to the vascular scaffolds in a stable, sterile and constant environment. The bioreactor exerted a strain on the vascular sheets, which was shown to alter cellular morphology and enhance cellular proliferation.

Successful Treatment of Acute on Chronic Mesenteric Ischaemia by Common Iliac to Inferior Mesenteric Artery Bypass

Chronic mesenteric ischaemia is a rare and potentially fatal condition most commonly due to atherosclerotic stenosis or occlusion of two or more mesenteric arteries. Multivessel revascularisation of both primary mesenteric vessels, the celiac artery and superior mesenteric artery (SMA), is the current mainstay of treatment; however, in a certain cohort of patients, revascularisation one or both vessels may not be possible. Arteries may be technically unreconstructable or the patient may be surgically unfit for the prolonged aortic cross clamping times required. Here we present a case involving a 72-year-old woman with acute on chronic mesenteric ischaemia. She was a high risk surgical patient with severe unreconstructable stenotic disease of the SMA and celiac arteries. She was successfully treated with single vessel revascularisation of the inferior mesenteric artery (IMA) via a common iliac to IMA reversed vein bypass. At two-year follow-up, the graft remains patent and the patient continues to be symptom-free and is maintaining her weight.

Regenerative medicine, tissue engineering and vascular surgery: twenty first century clinical challenges

Cardiovascular disease remains one of the leading causes ofdeath and illness in man. Currently available vascular pros-thetic devices are associated with significant risks of infec-tion, thromboembolism, degeneration and growth failure,especially in younger patients. Because of such problems,several groups of researchers are seeking to engineer humanorgans and tissues capable of replacing diseased and dam-aged native cardiovascular tissues [1]. Tissue engineering,defined as ‘‘an interdisciplinary field that applies the prin-ciples of engineering and life sciences towards the devel-opment of biological substitutes that restore, maintain, orimprove tissue function’’, offers the possibility of providinga true biological substitute with patient-specific properties[1, 2]. Vascular tissue engineering applies engineeringprinciples and techniques to restore the structure and func-tion of pathologically altered molecules, cells, and tissues ofblood vessels [3]. The major advantage of tissue-engineeredcardio-vascular tissues lies in their ability to grow, remodel,and repair in vivo without rejection. Moreover, such bio-logicaltissue-engineeredsubstitutesprovidepatientswithanalternative source of vascular conduits especially in caseswhere shortage of autologous and diseased veins is a prob-lem. In essence, tissue-engineered cardiovascular devicesoffer the possibility of developing a patient-specificimplantable device with the potential of growing alongsidenative tissue without the risk of rejection [4].The key components for developing processed biologicaltissues are cells, scaffolds, growth factors, hormones andnutrients, and a biologic environment provided by bioreac-tors[4].Severalmethodologiesforconstructingbloodvesselreplacements with biological functionality have emerged.The most common strategies include the use of cell-seededgels, cellself-assembly, cell-seeded biodegradable syntheticscaffolds and xenogeneic acellular materials [5].It has been more than two decades since Weinberg andBell [6] introduced the innovative concept of developing avascular graft from living tissue. Their graft combinedsynthetic and biological components; it was made of col-lagen integrated with Dacron mesh, smooth muscle cellsand a functioning endothelium. Recent advances in cellu-lar, scaffold and bioreactor technologies indicate that thegoal of producing purely tissue-engineered vascular tissueswith no synthetic components is now achievable anddevices may soon be available for clinical use [7, 8].Nevertheless, a number of significant problems remain tobe resolved before biological vascular grafts can be usedroutinely in the management of vascular disease.McAllister and colleagues [9] have recently reported thesuccessful implantation of a completely biologic tissue-engineered graft for vascular access in ten patients with endstage renal disease receiving haemodialysis. Patency rates at1 and 6 months were 78 and 60%, respectively. This is thefirst encouraging result of the use of a tissue-engineeredvascular graft in a clinical setting. McAllister et al. used thecell self-assembly technique (as opposed to cell-seeded gelsor cell scaffold technology) for the construction of theirtissue-engineered vessel. In this approach, first described byL’Heureux in 1998 [10], human tissue-engineered vesselsare constructed by taking advantage of the natural ability of

Venous drainage, a simple method to prevent the systemic consequences of ischaemia-reperfusion injury in acute lower limb ischaemia.

BackgroundIschaemia–reperfusion injury (I–R injury) is a recognised and potentially fatal complication following revascularisation of an ischaemic limb. Prevention of reperfusion injury is the focus of much research, but effective drug regimens have yet to be established into clinical practice.Case report Here we present a man with prolonged, severe lower limb ischaemia, successfully treated with a novel surgical technique for preventing I–R injury. Prior to revascularisation, the common femoral vein was cannulated and the harmful venous effluent was drained. The patient made an excellent recovery, the limb was salvaged and no systemic complications were encountered.