Search PubMed⌕ Search

Biomedical subjects

L R King

Publications and source records attributed to L R King.

At least 55 records · Page 3Linked to original sources

Natural history of fetal and neonatal hydronephrosis.

Since pyelocalicectasis alone is common in fetuses, we reviewed reports of fetal hydronephrosis that resolved spontaneously or at birth. Severe fetal hydronephrosis with calicectasis or parenchymal thinning rarely resolves spontaneously before or after birth. We also reviewed the clinical and experimental literature on renal hypertrophy. After unilateral nephrectomy in neonatal animals or after birth with congenital absence of one kidney in humans, the remaining kidney hypertrophies very quickly. In infants and young animals, the eventual size of the remaining kidney is inversely proportional to the age at which one kidney is lost. This improvement in residual renal function seen after renal loss in infancy, compared with older children, itself constitutes a strong argument for early relief of obstruction. If contralateral renal hypertrophy has occurred, the treated damaged kidney may resume growth in parallel with its hypertrophied mate but does not become as large or recover normal potential for growth. In other words, if correction of a unilateral obstruction is deferred until contralateral hypertrophy occurs, the obstructed kidney then has less potential for recovery of function.

Animals↗

Hypertension and multicystic kidney.

The optimal management of the asymptomatic patient with a multicystic kidney remains a dilemma. The risk of nephrectomy in a neonate or infant with this lesion is small and the morbidity is minimal. The alternative to elective nephrectomy is life-long follow-up with blood pressure determinations, beginning in infancy. We report herein two infants with multicystic kidney (MCK) in whom hypertension was cured by its removal. Since accurate blood pressure measurements are relatively difficult to obtain in infants and since periodic long-term follow-up is difficult in the best of circumstances, we are concerned that hypertension caused by a retained MCK goes undiagnosed perhaps more frequently than a review of the current literature suggests. Such hypertension may result in contralateral renal damage and arteriosclerosis, so that later removal of the MCK may not have a beneficial effect on the elevated blood pressure.

Female↗

The use of biofeedback in a behavioral program designed to teach an anxious child self-catheterization.

This paper presents a case study of a 7-year-old girl with a noncompliant bladder who was trained to self-catheterize using biofeedback and behavior therapy techniques. Initial attempts to train her to self-catheterize were unsuccessful owing to excessive amounts of fear, muscle tension, and refusal. After seven treatment sessions in which she was instructed in proper self-catheterization technique by a urology nurse clinician and coached in biofeedback-assisted relaxation by a clinical psychologist, the child successfully learned to self-catheterize. EMG readings showed a decrease in quadriceps muscle tension levels across sessions. Eight additional sessions were held in order to train the child's parents in proper technique and coaching procedures. Through the use of portable biofeedback equipment during actual training sessions, the biofeedback served as a cue--first to the child and coach, and later to the child and parents--for when the child needed to stop and relax. This case illustrates the usefulness of biofeedback in a comprehensive behavioral program designed to teach self-catheterization to fearful children.

Anxiety↗

Tolerance to oxotremorine's effects on schedule-controlled behavior in physostigmine-tolerant rats.

Tolerance to the effects of physostigmine and oxotremorine in rats was evaluated using a multiple fixed-ratio 10, extinction schedule of food presentation. Physostigmine was administered either once daily or three times daily for 18 consecutive days. Tolerance to physostigmine's response decreasing effects was observed under both administration regimens. Cumulative dose-effect functions for oxotremorine (0.0056-0.562 mg/kg) were determined before and after chronic physostigmine administration. Oxotremorine's potency to produce response rate suppression decreased in rats receiving physostigmine three times daily but did not substantially change in rats receiving single daily injections. These results demonstrate that the dose or duration of action of physostigmine can determine whether tolerance to physostigmine's effects is accompanied by cross-tolerance to oxotremorine's effects.

Animals↗

Ileocecal ureterosigmoidostomy: an alternative to conventional ureterosigmoidostomy.

We describe a 1-stage procedure that involves use of the ileocecal segment as an intervening urine conduit to the large bowel to achieve a continent diversion. The ureters are anastomosed end to end to the terminal ileum that is intussuscepted into the cecum. The cecum then is joined to the lower sigmoid by an end-to-side anastomosis. Mixed urine and feces are eliminated through the rectum. The results in 5 patients with exstrophy and 1 with epispadias between 5 months and 13 years old are reported. Ureteral reflux was not observed. Urinary tract infection developed in 2 patients. Ileocecal ureterosigmoidostomy is a reasonable alternative to intact ureterosigmoidostomy that may reduce the risk of development of cancer.

Adolescent↗

The clinical effectiveness of pneumococcal vaccine in the elderly.

The effectiveness of pneumococcal vaccine in the immunocompetent elderly remains controversial. We report the results of a multicenter, case-control study of 244 controls and 122 patients, aged 55 years and older, hospitalized during a 5-year period with pneumococcal bacteremia, meningitis, or other bacteriologically confirmed pneumococcal infection. Two controls per patient were matched on the basis of admission date, hospital records, and underlying diseases. All subjects were selected without knowledge of immunization status with pneumococcal vaccine, and were excluded if there was evidence for immunosuppression due to disease or iatrogenic causes. The clinical effectiveness of the vaccine was calculated to be 70% (95% confidence intervals [CI], 37% to 86%) in this population, based on a Mantel-Haenszel point estimate of the odds ratio of 0.30 (95% CI, 0.14% to 0.63%; P less than 0.005). The clinical effectiveness of pneumococcal vaccine in preventing pneumococcal infection in the immunocompetent elderly approximates the vaccine's effectiveness in the general immunocompetent population.

Aged↗

Experiences with bladder reconstruction in children.

The results in 56 children (28 with neurogenic bladder dysfunction) undergoing enterocystoplasty between 1981 and 1985 are presented. Ileal, ileocecal, right colon and sigmoid segments were used in tubular and opened configurations. Our experience leads us to recommend opened ileal segment reconstruction in neurogenic bladder patients and those with weak anal sphincters generally, and open ileocecal or open right colon segments in patients with other etiologies. Continence was achieved in 53 patients, although secondary procedures, particularly at the bladder outlet, were required in 13. When ureteral reimplantation was required we achieved excellent success with normal-sized or mildly dilated ureters regardless of the operative technique used. Initial failures to prevent reflux in the face of marked ureterectasis using the ileocecal valve have been resolved by a modified technique of intussusception and fixation. An over-all favorable experience is reported, which we believe permits us to formulate certain rules that will improve the acceptability and success of bladder reconstruction in general.

Adolescent↗

Renal dysgenesis and cystic disease of the kidney: a report of the Committee on Terminology, Nomenclature and Classification, Section on Urology, American Academy of Pediatrics.

We believe that the confusion regarding abnormal renal development could be reduced by more precise terminology. Therefore, we suggest precise definitions for dysgenesis, hypoplasia, dysplasia, hypodysplasia, aplasia and agenesis of the kidney. We suggest the term reflux nephropathy be a generic label for any instance of abnormal renal morphology (gross or microscopic) associated with vesicoureteral reflux. Hypoplasia and hypodysplasia can be subclassified on the basis of associated urological criteria. There have been many previous attempts to classify cystic disease of the kidney but none has been accepted collectively by pathologists, urologists, nephrologists and radiologists. On the basis of known patterns of inheritance, a classification is outlined in which renal cystic disease is divided into 2 major groups: genetic and nongenetic. Each entity is discussed.

Classification↗

Augmentation and replacement cystoplasty: sonographic findings.

Sonographic evaluation of the urinary tract after bladder augmentation and replacement procedures often reveals unexpected findings that result from incorporation of bowel into the urinary bladder wall. Familiarity with such findings is important to avoid misinterpreting them as abnormalities. The authors reviewed the sonograms of 47 patients. The most common findings were thick or irregularly shaped bladder walls (96%), pseudomasses within the bladder lumen (89%), and fine debris or linear strands (47%). Pseudomasses were potentially the most confusing; they are usually attributable to normal bowel folds, intraluminal mucus collections, or segments of bowel that have been intussuscepted into the bladder to prevent reflux.

Adolescent↗

Percutaneous balloon dilatation of ureteral strictures.

Percutaneous balloon dilatation of ureteral strictures has not gained widespread acceptance, despite proven success with the techniques for dilating stenotic blood vessels. Thirty-one ureteral strictures (in 30 patients) that were dilated during a 42-month period were reviewed to assess the results and to determine which patients are most likely to benefit from the procedure. Eighteen (58%) of 31 strictures were successfully dilated and remained patent for at least 6 months. Thirteen (42%) of 31 strictures resulted in failed patency either immediately (two patients) or within 3 months (seven patients), 6 months (three patients), or 21 months (one patient). Fourteen (64%) of 22 strictures less than 7 months of age were successfully dilated. All dilations for strictures more than 7 months of age failed. Four strictures were of unknown age. Nine (69%) of 13 strictures located in the proximal or midureter remained patent, and three (60%) of five dilations at a ureteroileal anastomosis were successful. Neither of two strictures at a ureterocolic anastomosis was treated successfully. We conclude that percutaneous balloon dilatation is an effective treatment of ureteral strictures in some patients, especially when the strictures are less than 7 months of age.

Adult↗

Comparison of autogenous fistula versus expanded polytetrafluoroethylene graft fistula for angioaccess in hemodialysis.

A hundred patients with RCAV fistulas we compared with 100 patients with expanded PTFE fistulas created during the same time period. The fistulas were analyzed to compare early and late thrombosis, life table patency, infection rate, venous hypertension, and vascular steal. There was a significantly greater incidence of early thrombosis in the RCAV fistula group. Late thrombosis was seen with equal frequency in both groups. Thirty month patency by life table analysis favored the RCAV group to a significant degree, whereas infections, pseudoaneurysms, venous hypertension, and vascular steal were all more common in the expanded PTFE group. The RCAV fistula remains the ideal form of access but it is less frequently available for women and patients with peripheral vascular disease. Utilization of the expanded PTFE loop fistula requires closer observation and maintenance to keep it functional. Improved methods of patient selection for RCAV fistula using ultrasonographic imaging may allow for increased use of this form of access. Improvement in early patency in RCAV fistulas will magnify the superiority of RCAV fistulas in comparison to expanded PTFE fistulas, however, a prolonged period of venous maturation may be necessary to improve early function.

Adolescent↗

Balloon dilation of upper ureteral strictures in primates.

We report the successful creation of ureteral strictures in primates and their successful management by balloon dilation 3 months later without ureteral stenting. This experimental work confirms the sporadic clinical reports of the effectiveness of balloon dilation in the management of ureteral strictures and suggests that ureteral stenting is not necessary for a successful result.

Animals↗

Ileocaecocystoplasty in urinary tract reconstruction in children.

Ten children have undergone lower urinary tract reconstruction by ileocaecocystoplasty. Four patients had previously been diverted and the other six were reconstructed because of intractable incontinence or deteriorating renal function. Continence was primarily achieved in eight patients and renal function improved or remained stable in all 10. Reflux was prevented by a plicated ileocaecal valve in five of eight patients. Continued pharmacological manipulation, intermittent self catheterisation and secondary surgical intervention were frequently necessary in these patients who required careful counselling and follow-up.

Adolescent↗