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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In spite of the fact that the operations after B. N. Khol'tsov, P. D. Solovov, and V. I. Rusakov have found a wide recognition and use, the rate of complications and poor results remains still high, reaching 3-29%. The authors consider that one of the reasons for poor outcomes in such operations is evolving urethral ischemia at the site of anastomosis, which is caused by compression of tissues with suturing material with the routine suturing of urethral ends through all its layers. The experiment with the male dogs and human cadavers provided evidence for this assumption. The mathematical calculation indicated that with the sutures applied, over 12-16% of the urethral tissue volume became ischemic at the site of anastomosis. A new technique was proposed to attach the ends of the resected urethra, which eliminates the suture of the urethral ends through all the layers. The essence of the technique is that after resection, the ends of the urethra are opposed and fixed with the outer layers without suturing the urethra via all the layers with 6 stitches. Twenty nine patients were operated on in this fashion. Twenty eight patients were discharged with recovered micturition. A relapse occurred in one patient with inflammatory urethral stricture. For 3 months to 3 years, 22 subjects were examined, another patient had a relapse 3 months following surgery. The two patients were reoperated, with a good effect. The remaining patients reported normal micturition and presented no complaints.
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PMID:[A method for joining the ends of the resected urethra]. 227 61

Local effects of indwelling urinary catheters are poorly characterized. Latex catheter brands of various degrees of tissue toxicity were implanted into the urethra of 27 male piglets. The systemic hemodynamic states varied from normal to hypovolemia, where the circulation changes simulated the extracorporeal perfusion used in open-heart surgery. The urethral epithelial changes caused by the catheters were studied by light ad scanning electron microscopy (SEM). The blood circulation in paraurethral tissue reacted strongly to systemic hemodynamic changes. A reduced local blood flow induced an accumulation of polymorphonuclear leucocytes in the urethral epithelium and subepithelial space in connection with implanted latex urinary catheter strips. This was not seen in normovolemic piglets. Non-toxic wholly silicone control catheter implants did not induce changes. Epithelial cell damage correlated with the tissue toxicity values of implanted catheter strips. In SEM analysis destruction of microvilli and cell membranes was also discovered in connection with a latex catheter brand regarded as non-toxic. The wholly silicone catheters did not cause any detectable changes. The observed cell damage is induced by toxic chemicals dissolving from latex catheters. Local ischemia exacerbates these toxic effects and activates complement cascade. This induces polymorphonuclear granulocyte accumulation in the damaged urethral epithelium leading to demolition and urethral fibrotization. The present findings explain the etiology of the long urethral stricture epidemics seen in open-heart surgery in the early 1980s by showing the interference between indwelling latex catheters and reduced local blood flow.
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PMID:Toxic catheters and diminished urethral blood circulation in the induction of urethral strictures. 378 Aug

Ischial ulcers are the most common pressure sores in spinal cord injury patients and ischiectomy often is used in the over-all management. Because a high percentage of spinal cord injury patients with total ischiectomy had complications of the membranous and proximal bulbous urethra, we evaluated urodynamically 15 ischiectomy patients in the supine and sitting positions to determine if pressure usually borne by the ischial tuberosities was transmitted to the membranous and proximal bulbous urethra. Of the 8 patients with a complete ischiectomy at least on 1 side 5 had problems of the membranous and proximal bulbous urethra, and the average urethral pressure increase from the reclining to the sitting position was 111 cm. water. The increase in urethral pressure was not related to any change in bladder or abdominal pressure. The average urethral pressure increase in the nonischiectomy patients was only 16 cm. water and none had any problems of the membranous and proximal bulbous urethra. Some retrospective clinical studies have implicated ischiectomy in the development of these urethral complications. Our urodynamic data lend some direct evidence that a more complete ischiectomy results in excessive urethral pressure with the patient in the sitting position, thereby predisposing the membranous and proximal bulbous urethra to problems related to ischemia. Five of the 8 patients with more complete ischiectomy and 1 with bilateral partial ischiectomy had high urethral pressures and complications, such as pseudodiverticulum, diverticulum and dilatation. More incomplete ischiectomy should be used to obviate this urethral damage.
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PMID:Urethral complications following ischiectomy in spinal cord injury patients: a urethral pressure study. 380 14

An in-utero experimental study was performed to evaluate the effects of intrauterine vascular compromise on further development of corpus spongiosum and male urethra. Thirty time-mated pregnant New Zealand white rabbits on their twenty-third day of gestation were used. Deterioration of the blood supply of the corpus spongiosum and urethra was attempted by electrocauterizing the perineum adjacent to the root of the phallus without damaging the corpus spongiosum and urethra, under the operating microscope. A bipolar cautery was carried out using a specially designed forceps having 100 microns interspaced fixed tips. Five experimental and seven control live male litters were delivered at term by Cesarean sections. Their anogenital regions were examined histopathologically. While the corpus spongiosum extended as long as the corpus cavernosum to the tip of phallus in control litters, the corpus spongiosum ended under the skin in one of the experimental group and in the other four was shorter than the corpus cavernosum. In the latter group, no histopathological evidence of tissue destruction which might be related to electrocauterization, was found. Similar to the pathogenesis encountered in intestinal atresia, a vascular insult which might occur even after the completion of organogenesis, may affect the fate of the corpus spongiosum and urethra. Localized ischemia resulting from local vascular insults may explain, at least in theory, the pathogenesis of some congenital anomalies of corpus spongiosum and urethra such as hypospadias.
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PMID:The effect of intrauterine vascular compromise on further development of corpus spongiosum and urethra. 819 28

The use of artificial urinary sphincter around the urethra or bladder neck for the management of urinary incontinence secondary to intrinsic urethral sphincter deficiency is now well accepted. However, its use around the bowel to serve as a sphincter in urinary pouches is still anecdotal. Its use in experimental models has been met with failure because of ischemic bowel necrosis at the cuff site. To obviate these difficulties, a new technique was devised using a flap of rectus muscle that acted as a cushion between the cuff and the bowel wall. Results in five dogs showed that bowel wall ischemia is avoided with cuff pressure of 51-60 cm applied constantly for four weeks while providing pressure to leak around the closed cuff with a pressure of 62-75 cm water. Further study is needed to confirm the long-term effect of this technique on the bowel wall and the ability of the sphincter to maintain continence.
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PMID:Use of artificial sphincter to bowel segment using rectus muscle interposition. 844 13

Eighty-five patients with hemospermia were examined with blood tests, sperm culture, transrectal US (TRUS) and cystourethroscopy. Blood tests and sperm culture demonstrated bacterial inflammation in 48 patients (56.47%). At cystourethroscopy, the urethra was normal or hyperemic in all patients. TRUS demonstrated 40 cases (47.05%) of periurethral calcifications and also with calcifications in the two glandular lobes. TRUS also demonstrated prostatic inflammation in progress or its outcome in 21 patients (24.70%), ectasia and seminal vesicle inflammation in 10 patients (11.76%), a prostatic tumor in 3 patients (3.52%). No patient had cysts, stones or cancers in the seminal vesicles. In 11 patients (12.94%), no specific cause of hemospermia was detected, even though 4 of these patients (4.70%) had received anticoagulants for former heart ischemia. Benign prostatic hypertrophy was found in 44 patients (51.76%) but we did not consider it a possible cause of hemospermia because of the high frequency of this condition in the male population. To conclude, TRUS could demonstrate the cause of hemospermia in most of our patients, which makes us suggest it as the diagnostic technique of choice in the patients with ejaculatory conditions, after clinical exams and laboratory tests, because it allows to study the prostate, the seminal vesicles and the urethra.
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PMID:[Transrectal prostatic echography in the study of hemospermia. An assessment of an 85-patient case load]. 864 53

This is a case report of polytrauma in a 4-year-old boy who sustained a rare aorto-iliac dissection injury along with pelvic fracture and rupture of posterior urethra. This child was initially treated for the rupture of posterior urethra and extravasation of urine with suprapubic cystostomy and drainage. Lower limb ischemia developed later. Exploration showed aorto-iliac dissection injury for which aorto-iliac replacement grafting was carried out. Subsequently delayed repair of posterior urethral rupture by transpubic urethroplasty was carried out.
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PMID:Rare traumatic aorto-iliac dissection injury in a child with pelvic fracture and urethral rupture: a case report. 912 75

Prostatic urethral strictures are rare. We present 3 cases in a study group of 27 who underwent high energy transurethral microwave therapy for benign prostatic hyperplasia. In all 3 cases, midprostatic strictures with ectopic area proximal to the stricture were seen by cystoscopy. Two of the strictures were urodynamically significant. The most likely explanation for their occurrence is direct damage of the prostatic urethra due to ischemia or heat damage of the prostatic urethra.
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PMID:Prostatic urethral strictures after transurethral microwave thermal therapy for benign prostatic hyperplasia. 942 38

In electrically stimulated (dynamic) graciloplasty for urinary incontinence, the gracilis muscle is transposed into the pelvis, and the distal part is used to reconstruct a neosphincter. Clinical outcomes using this technique have been disappointing due to stricture of the urethra caused by ischemia in the distal part of the gracilis and limited gracilis length available for neosphincter construction. Furthermore, the urethra is twisted by the contracting gracilis, rather than circumferentially squeezed. The purpose of the present study was to test the anatomical and functional feasibility of a new surgical approach to reconstruct a urinary sphincter, using the gracilis muscle as a free flap. In 12 human cadavers, the anatomical feasibility for creating a neosphincter by using the gracilis free flap was determined. In all cases, transfer of the gracilis muscle into the pelvis as a free flap (with the nerve intact) was feasible, and ample muscle was available to construct a neosphincter around the bladder neck. Gracilis neosphincter function was studied in seven dogs. The left gracilis muscle was subjected to transfer into the pelvis as an innervated free flap to create a neosphincter around the urethra. The right (control) gracilis muscle was lifted as a single pedicle flap, remained in situ, and was wrapped around a stent to mimic the urethra. Function (expressed as peak pressure generation and fatigue rate) and surface perfusion were determined for all gracilis muscles. In each dog, both sides were compared using the paired Student's t test for statistical analysis, and no significant difference was measured for the two groups. In conclusion, an innervated gracilis free flap can be used to create a neosphincter around the bladder neck. In an acute study in dogs, function and perfusion of the innervated gracilis free flap are not compromised.
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PMID:Electrically stimulated free-flap graciloplasty for urinary sphincter reconstruction: a new surgical procedure. 965 11

A vesicovaginal fistula is an abnormal passage between the bladder and the vagina. It is a hole in the lower posterior wall of the bladder and sometimes the urethra through which urine continuously drips toward the vagina, without possibility of control. Since women suffering from vesicovaginal fistulas are commonly infertile, the problem affects their entire social, family and gyneco-obstetrical lives. Fistulas are a complication of difficult deliveries and occur frequently in some rural and isolated regions of Africa insufficiently served by maternity hospitals. Fistulas develop in the course of deliveries prolonged by any cause when the baby's head presses against the bladder wall, causing necrosis of the wall by ischemia. The fistula appears several days after delivery of an usually stillborn infant. Fistulas are most commonly seen in young women, over half of whom are primiparas. Risk factors include small stature with narrow pelvis and excision. But the lack of obstetric care and midwives in rural zones and the difficulty of transfer to a hospital are the major factors. The fistula may measure several mm to several cm in length. The bladder has a reduced capacity because of sclerosis. The fistula may affect the urethra, uterus, vagina, and in very severe cases the rectum. Continuous local and urinary infection is almost always present. Early diagnosis is important because treatment is simpler, but it is more difficult than later diagnosis and symptoms may be masked by postpartum incontinence caused by trauma to the perineum which usually regresses spontaneously. An evaluation of the size and exact location of the fistula and the condition of the bladder and other affected organs is necessary before corrective surgery can be planned. 1 or 2 weeks of preoperative preparation may be needed to treat anemia, parasites, urinary infections, and cutaneous lesions. Treatment may require from several weeks to several months. Numerous surgical procedures are possible. The choice depends on the lesions and the habits of the surgeon. Curative surgery may not be possible in the most severe cases. Palliative surgery requires careful longterm follow-up that is seldom possible in Africa. When the final outcome is good, the patient must be carefully advised that hospital care is imperative during any subsequent pregnancies to avoid another fistula. Prevention in the form of screening of difficult deliveries and transfer to the nearest hospital at any moment is the best form of treatment for this condition.
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PMID:[Vesico-vaginal fistulas]. 1228 72


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