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M E Mitchell

Publications and source records attributed to M E Mitchell.

At least 73 records · Page 4Linked to original sources
PubMed1993

Measurement strategies in social support: a descriptive review of the literature.

Social support literature has been criticized for lacking methodological clarity. The purpose of this study was to conduct a systematic descriptive review of the social support literature, outline measurement problems, identify the nature of assessment inadequacies, and provide recommendations for the future. Two-hundred sixty-two empirically based articles published between 1980 and 1987 were reviewed comprehensively. Information about social support measurement and sample characteristics was obtained. A system was designed to organize the data on sample characteristics, type of instrument, source of support assessed, and category of support measured. The social support literature also was described from a methodological perspective, and several trends were identified. Conclusions about conceptual maturity, a priori biases, measurement of network utilization, and social support sources are discussed.

Adult↗
PubMed1993

Urethral polyp presenting as interlabial mass in young girls.

We describe two young girls who presented with an interlabial mass. Histologic examination of each excised mass revealed a benign urethral polyp covered with transitional and squamous epithelium. Urethral polyps should be included in the differential diagnosis of an interlabial mass in young female patients.

Child, Preschool↗
PubMed1993

Aggressive surgical and medical management of autosomal recessive polycystic kidney disease.

The treatment of autosomal recessive polycystic kidney disease (ARPKD) is evolving. Overall prognosis is difficult to determine, but most neonates without severe pulmonary hypoplasia will survive. It is difficult to predict which neonates with ARPKD requiring immediate ventilatory support have pulmonary hypoplasia incompatible with survival. Massively enlarged kidneys restricting diaphragmatic excursion can cause respiratory distress in addition to pulmonary hypoplasia. Three infants with ARPKD underwent bilateral nephrectomies and institution of peritoneal dialysis in an attempt to improve ventilatory status and assess long-term pulmonary function. Two children are alive at twelve and thirty months postoperatively and awaiting renal transplantation. One infant died of acute cardiorespiratory complications.

Child, Preschool↗
PubMed1993

Bladder outlet reconstruction: fate of the silicone sheath.

The placement of a 1.5 cm. wide silicone sheath around a newly constructed urethra/bladder neck to ensure maintenance of repair length and to facilitate future placement of a sphincter cuff was reported by our institution in 1985. We present our long-term followup and new recommendations for use of the silicone sheath. A total of 15 silicone sheaths was placed between March 1981 and July 1984. Of the sheaths 14 were placed at the time of urinary reconstruction around the Young-Dees-Leadbetter bladder neck repair and 1 was placed after erosion of an artificial urinary sphincter cuff. Of the 15 sheaths 10 have eroded into the urethra and 4 sheaths remain in situ. Another sheath was replaced 2 years after its original insertion with an artificial urinary sphincter cuff. Mean time to erosion was 48.2 months, with a range of 2 to 108 months. Long-term followup of 10 patients revealed that 4 ultimately required ligation of the bladder neck and construction of continent stoma after erosion, 1 is dry after placement of a bulbar artificial urinary sphincter, 2 remain dry after removal of the eroded sheath alone, 2 required bladder neck revision to achieve continence after erosion and the most recent patient remains diverted with a suprapubic tube. All 4 patients with sheaths still remaining are dry without evidence of erosion (mean duration 116 months). These long-term results using a silicone wrap around a newly constructed bladder neck reveal an unacceptably high rate of erosion. Therefore, we no longer recommend or support the use of the silicone sheath in the manner we have described for bladder neck reconstruction.

Adolescent↗
PubMed1993

The syndrome of dysuria and hematuria in pediatric urinary reconstruction with stomach.

Between July 1989 and March 1992 at a single institution 27 male and 30 female patients underwent lower urinary reconstruction with stomach. Mean patient age was 9.9 years (range 1.5 to 28 years). The diagnoses were epispadias/exstrophy complex (19 patients), myelodysplasia (11), cloacal exstrophy (6), posterior urethral valves (6), Hinman syndrome (4), sacral agenesis (3) and other (8). Indications for surgery were urinary incontinence, upper tract deterioration or undiversion. A total of 54 patients underwent augmentation gastrocystoplasty and 3 had total bladder replacement. Mean followup time was 23.2 months (range 12 to 39 months). The syndrome of dysuria and hematuria is defined as 1 or a combination of the following symptoms: bladder spasm or suprapubic, penile or periurethral pain, coffee brown or bright red hematuria without infections, skin irritation or excoriation and dysuria without infections. Telephone and clinic interviews identified 21 patients (36%) with symptoms of the dysuria and hematuria syndrome. The most common symptoms were hematuria (71%) and bladder or suprapubic pain (76%). Of the patients 18 (86%) ranked the severity of symptoms as mild to moderate and 3 (14%) ranked them as severe. No medications were required to control the symptoms in 13 patients (62%) and 3 other patients only required medications on an as needed basis. Overall patients who required no medications had lower symptom scores than those who required medications. Patients with decreased renal function may be more at risk for the dysuria and hematuria syndrome than those with normal renal function. Patients who were wet were more prone to have the dysuria and hematuria syndrome than those who were totally dry. The pathophysiology of the dysuria and hematuria syndrome is currently unknown. Patients who require urinary reconstruction with stomach tissue need to be made aware of the potential of the dysuria and hematuria syndrome.

Adolescent↗
PubMed1993

The use of the AMS800 artificial urinary sphincter in combination with the gastric tube for continence in the canine model.

An experimental canine model was designed to examine the potential use of the artificial urinary sphincter around a gastric tube. The artificial urinary sphincter was placed around a tubularized gastric flap as part of a continent gastric reservoir in 4 dogs and in 2 additional dogs the gastric tube was anastomosed to the native bladder. Two dogs underwent placement of the artificial urinary sphincter around the gastric tube 4 weeks postoperatively and the remainder had the sphincter placed simultaneously with creation of the gastric tube. All dogs with the gastric reservoir underwent urodynamics before and after activation of the sphincter. Only 61 to 70 cm. water pressure balloons were used. All dogs were continent postoperatively on clean intermittent catheterization every 8 hours. There were no erosions or problems with catheterization. Urodynamics confirmed a complaint system and an average increase of capacity of 410% after artificial urinary sphincter activation (4 dogs). There was no leakage at capacity. Histology of the artificial urinary sphincter and neighboring (control) regions, and of the reservoir at 1 (2 dogs), 3 (3 dogs) and 6 months (1 dog) was obtained. Microscopic examination of the cuff site showed mild serosal hyperplasia and fibrosis, a well preserved muscularis and mild to moderate focal mucosal atrophy. These changes were slightly more evident at 6 months. Mucosal folds were well preserved with normal submucosa and lamina propria. In the control region histology was well preserved and similar to native stomach. We conclude that the artificial urinary sphincter around a gastric tube can provide urinary continence. The minimal changes in histology under the cuff are encouraging and support the potential for use of the gastric tube with the artificial urinary sphincter, although longer term effects are unknown.

Animals↗
PubMed1993

The Mitrofanoff principle in urinary reconstruction.

We report the use of the Mitrofanoff principle to achieve urinary continence in 47 patients. A catheterizable channel can be used as the primary continence mechanism, or as an adjunct to ensure complete bladder emptying if urethral catheterization or voiding is inadequate. Appendico-vesicostomy was performed in 25 of 47 patients (55%). Satisfactory continence was achieved in 45 patients (96%). Bladder emptying by clean intermittent catheterization was performed in all patients. Early complications included peristomal abscess (1 patient) and small bowel obstruction (1). Late complications included difficulty with catheterization (5 patients), stomal stenosis (9) and persistent incontinence (2). Our results support use of the appendix as the catheterizable segment of choice. We describe the technique and discuss the management of complications.

Appendix↗
PubMed1993

Ureteral obstruction due to compression by the vas deferens following Fowler-Stephens orchiopexy.

A rare complication following a difficult unilateral 1-stage Fowler-Stephens orchiopexy resulting in ipsilateral distal ureteral obstruction is reported. To our knowledge excessive vasal traction during orchiopexy causing partial obstruction at the ureterovesical junction has not been previously described. The complication arose when the transected spermatic vessels allowed tension to be placed solely on the vas when the testis was placed in the scrotum. The vas in turn compressed the ureter during bladder filling.

Child, Preschool↗
PubMed1993

Use of a double cuff AMS800 urinary sphincter for severe stress incontinence.

Stress urinary incontinence in the male patient has been successfully treated with the artificial urinary sphincter. However, approximately 15% of the patients treated are still significantly wet despite some improvement with this device. These patients usually are almost totally incontinent before artificial sphincter implantation. Of 15 such patients 80% were rendered satisfactorily dry by adding a second sphincter cuff around the bulbous urethra. This double cuff technique increases the success rate with the AMS800 sphincter to greater than 95%.

Adolescent↗
PubMed1993

Lower urinary tract reconstruction using stomach and the artificial sphincter.

We implanted the artificial urinary sphincter at gastrocystoplasty in 13 male and 5 female patients. The diagnoses were classical bladder exstrophy (8 patients), myelodysplasia (8), cloacal exstrophy (1) and bilateral ectopic ureters (1). Mean patient age was 14.3 years (range 7 to 32.5). Six patients (5 with bladder exstrophy and 1 with clocal exstrophy) had failed bladder neck continence procedures, 3 myelodysplastic patients had failed artificial urinary sphincter placement, and 1 exstrophy patient had failed a Young-Dees bladder neck repair and artificial urinary sphincter placement. The sphincter cuff was placed around the reconstructed bladder neck in these patients, while in the remainder the artificial urinary sphincter was placed around the intact bladder neck. Mean followup was 20.3 months (range 1 to 5). Of the patients 16 (88%) are continent day and night, while 2 are wet. A total of 11 patients (61%) use Valsalva's maneuver alone for voiding and the remainder use Valsalva's maneuver and/or clean intermittent catheterization for bladder evacuation. Complications related to the artificial urinary sphincter were recurrent pump erosion requiring conversion to a Mitrofanoff continent stoma in 1 patient, and mechanical dysfunction requiring pump cuff and reservoir replacement in 3. There were no complications due to infection. Our report demonstrates that the combination of augmentation gastrocystoplasty and an artificial urinary sphincter leads to urinary continence and can allow for spontaneous urination. The rate of infectious complications is not increased when the 2 procedures are combined simultaneously.

Adolescent↗
PubMed1993

Surgical approach of choice for penetrating cardiac wounds.

One hundred nineteen patients suffered penetrating cardiac trauma over a 15-year period: 59 had gunshot wounds, 49 had stab wounds, and 11 had shotgun wounds. The overall survival rate was 58%. The most commonly injured structures were the ventricles. Twenty-seven patients had injuries to more than one cardiac chamber. Thirty patients had associated pulmonary injuries. Emergency thoracotomy was performed in 47 patients with 15% survival. Median sternotomy was used in 30 patients with 90% survival. Seventeen of the 83 patients with thoracotomies required extension across the sternum for improved cardiac exposure or access to the contralateral hemithorax. Only one patient with sternotomy also required a thoracotomy. All pulmonary injuries were easily managed when sternotomy was used. We conclude that sternotomy provides superior exposure for cardiac repair in patients with penetrating anterior chest trauma. We feel it is the incision of choice in hemodynamically stable patients. Thoracotomy should be reserved for unstable patients requiring aortic cross-clamping, or when posterior mediastinal injury is highly suspected.

Adult↗
PubMed1993

Improved results using a modification of the Young-Dees-Leadbetter bladder neck repair.

Forty-seven patients with primary total incontinence underwent bladder neck reconstruction (BNR) between 1978 and 1988. This included 31 patients with exstrophy/epispadias, 14 with myelomeningocele and 2 with caecoureteroceles. The patients were divided into 5 groups based on the type of BNR: Group 1--standard Young-Dees-Leadbetter (YDL) BNR; Group 2--YDL+Silastic sheath; Group 3--modified YDL; Group 4--Kropp BNR; Group 5--other BNRs. Group 1 included 18 patients with a 45% primary continence failure rate, a 44% reoperation rate and only a fair ability to void spontaneously after BNR. There were 11 patients in Group 3 with a 9% primary continence failure rate, a 27% reoperation rate and excellent post-operative emptying. None of the 3 patients in Group 4 was incontinent post-operatively, but they all required reoperation and had poor post-operative emptying. We feel that the modified YDL BNR provides better overall voiding and continence with less morbidity than the other bladder neck/urethral reconstructive procedures.

Adolescent↗
PubMed1992

Nicardipine: myocardial protection in isolated working hearts.

The effectiveness of the calcium antagonist nicardipine in protecting the ischemic myocardium was evaluated using the hemodynamic recovery of isolated working rat hearts subjected to hyperkalemic cardiac arrest followed by ischemia at 37.5 degrees C and 10 degrees C. Rat hearts (n = 51) received 20 mL of cardioplegia and were subjected to 27 minutes of ischemia at 37.5 degrees C. Group A (control) did not receive nicardipine. Groups B through F received nicardipine in the cardioplegia with total doses ranging from 2 micrograms to 6 micrograms. Group A had 46% survival of ischemia, whereas groups C (3 micrograms) and D (4 micrograms) had survival rates of 88% and 100%, respectively (p less than 0.05). The recovery of aortic flow after ischemia was 35% in group A, compared with 76% in group B (2 micrograms) and 81% in group D (p less than 0.05). Group A had 49% postischemic recovery of cardiac output, whereas groups B and D had 82% and 85% recovery (p less than 0.05). The postischemic recovery of stroke volume was 48% in group A compared with 84% in group B, 87% in group D, and 73% in group E (5 micrograms) (p less than 0.05). Additional rats were exposed to 210 minutes of ischemia (n = 41) or 240 minutes of ischemia (n = 56) at 10 degrees C. Control groups did not receive nicardipine, whereas treatment groups received nicardipine in the cardioplegia with total doses ranging from 1.4 micrograms to 6.4 micrograms. There were no significant differences in the survival of ischemia or the recovery of function after ischemia at 10 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Treatment of bladder dysfunction in children with end-stage renal disease.

The appropriate management of the urinary bladder in patients requiring a renal transplant is significantly different in children than in adults. The etiology of end-stage renal disease (ESRD) in 13 of 50 children (26%) transplanted since 1985 was obstructive uropathy/dysplasia. Five of these children had small-capacity, poorly compliant bladders. Our current approach is to restore bladder compliance, improve emptying, and transplant into the restored bladder rather than divert. Pretransplant gastrocystoplasty was performed in three children and the donor ureter was implanted into the augmented bladder. One child awaits transplantation following his bladder augmentation. Bladder function is followed postoperatively by voiding cystourethrography (VCUG) and urodynamics. All of the children who have received transplants into augmented bladders are infection-free, voiding per urethra, and have functioning allografts. We recommend: (1) an initial VCUG in all children; (2) complete urodynamics, if appropriate; (3) urological reconstruction to include augmentation prior to transplantation; (4) transplantation into the reconstructed bladder; and (5) comprehensive follow-up including regular urodynamic assessment.

Adolescent↗
PubMed1992

Controlled study of meso-2,3-dimercaptosuccinic acid for the management of childhood lead intoxication.

We examined the efficacy and safety of meso-2,3-dimercaptosuccinic acid (DMSA) in children with markedly elevated blood lead (BPb) concentrations. Among 19 children with BPb concentrations of 50 to 69 micrograms/dl (2.41 to 3.33 mumol/L) who received a 5-day inpatient oral course of DMSA (1050 mg/m2 per day), the mean BPb concentration decreased by 61%; in four who received calcium disodium ethylenediaminetetraacetic acid (CaNa2EDTA) (1000 mg/m2 per day intravenously), it decreased by 45% (p less than 0.0007). Urinary lead excretion was comparable in both groups. Treatment with DMSA was more effective than treatment with CaNa2EDTA in restoring metabolic activity to the heme pathway and was well tolerated even among nine patients who received concomitant iron supplementation and two who had homozygous deficiency of glucose-6-phosphate dehydrogenase. On discharge, these 19 children received either no chelation therapy or DMSA, 350 or 700 mg/m2 per day for 14 days on an outpatient basis. After 14 days the mean BPb values for the no-chelation, low-DMSA, and high-DMSA groups were 73%, 66%, and 50% of the pretreatment values, respectively. We conclude that a 5-day oral course of DMSA is effective in the treatment of children with severe lead poisoning. In addition, on an outpatient basis the administration of DMSA, 700 mg/m2 per day, is capable of delaying the typical rebound in BPb values and should ultimately reduce the need for repeated hospitalizations.

Administration, Oral↗