A comparison of coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in patients on hemodialysis

The hospital records of 22 patients on hemodialysis undergoing coronary artery bypass grafting, and 19 others undergoing percutaneous transluminal coronary angioplasty were reviewed to compare the outcomes of these procedures in this population. Evidence of previous myocardial infarction or triple vessel or left main coronary artery disease was more common in patients undergoing coronary artery bypass graft than those undergoing percutaneous transluminal coronary angioplasty. Perioperative mortality and complication rates following coronary artery bypass graft (4.5% and 41%, respectively) were similar to those following percutaneous transluminal coronary angioplasty (5.3% and 42%). Cardiac event-free rates at 18 months by life-table analysis following coronary artery bypass graft and percutaneous transluminal coronary angioplasty were 87 +/- 16% and 40 +/- 14%, respectively. Survival at 18 months were 67 +/- 17% following coronary artery bypass graft and 69 +/- 14% following percutaneous transluminal coronary angioplasty. Cardiac events were observed to occur in three patients undergoing coronary artery bypass graft at a median of 10 months, and in nine patients following percutaneous transluminal coronary angioplasty at a median of 6 months. One patient required percutaneous transluminal coronary angioplasty after the initial coronary artery bypass graft. Seven patients required repeat percutaneous transluminal coronary angioplasty, and two patients underwent coronary artery bypass graft after initial percutaneous transluminal coronary angioplasty. Although these conclusions are limited by the retrospective nature of the study, it is concluded that coronary artery bypass graft can be performed with morbidity and mortality equivalent to percutaneous transluminal coronary angioplasty, and provides better cardiac event-free rates than percutaneous transluminal coronary angioplasty in patients on hemodialysis. Percutaneous transluminal angioplasty does not appear to be justified in this population because of its unacceptably high restenosis and cardiac event rates.

Interobserver reliability of detecting lumbar intervertebral disc high-intensity zone on magnetic resonance imaging and association of high-intensity zone with pain and anular disruption

STUDY DESIGN

Retrospective analysis of a spine imaging center's records of patients with chronic low back pain referred by tertiary care facilities.

OBJECTIVES

1) To assess the interobserver reliability of detecting lumbar intervertebral disc high-intensity zone on T2-weighted magnetic resonance imaging, and 2) to assess the relation between high-intensity zone and discography or post-computed tomography in symptomatic patients with low back pain.

SUMMARY OF BACKGROUND DATA

Two of the three previous studies on this subject found an association between high-intensity zone and the presence of Grade 4 anular disruption with discographic reproduction of patients' exact low back pain.

METHODS

Records of patients with low back pain who had undergone lumbar spine discography injection and post-computed tomography from June 1995 to August 1996 were reviewed. Two independent observers were asked to identify the presence of an high-intensity zone from the T12-L1 disc to L5-S1 on T2-weighted magnetic resonance images. With this data, interobserver reliability was assessed with the kappa statistic. Concordant high-intensity zone results were then compared with the Dallas Discogram rating for anular disruption and to patients' subjective pain response to discography injection. With this data, the sensitivity, specificity, and predictive values of high-intensity zone for detecting disc disruption and pain response were calculated.

RESULTS

The interobserver reliability for detecting a high-intensity zone in a given disc was fair to good (kappa = 0.57; 95% confidence interval = 0.44, 0.70). The sensitivity of high-intensity zone for detecting Grade 4 anular disruption and exact pain was poor (31%) but its specificity was relatively high (90%). The positive predictive value of a high-intensity zone was low (40%) for a severely disrupted and exactly painful disc.

CONCLUSIONS

The interobserver reliability of detecting a high-intensity zone and the positive predictive value of the presence of a high-intensity zone for detecting a severely disrupted and exactly painful disc were much lower than previous studies have shown. The relatively low positive predictive value may be attributable to differences in sample characteristics or procedural variations, or suggest that a high-intensity zone is not indicative of exactly painful internal intervertebral disc disruption.

Oral midazolam: pediatric conscious sedation

Dentists attempt to overcome patients' fears by using various oral, intramuscular, intravenous, and inhalational anxiolytic agents. This article discusses the use of oral midazolam as an alternative to oral diazepam in the management of the pediatric patient.

Congenital diaphragmatic hernia associated with aortic coarctation

Congenital diaphragmatic hernia (CDH) may be associated with other anomalies, most frequently cardiovascular in nature. Despite fetal echocardiography, diagnosis of an accompanying cardiac malformation often is not made until after birth and sometimes not until after extracorporeal membrane oxygenation (ECMO) has been instituted. Aortic coarctation associated with CDH may occur as an isolated, surgically correctable malformation or it may be a component of the usually fatal left heart "hypoplasia" or "smallness" syndrome. The authors present two cases of aortic coarctation associated with CDH requiring ECMO that illustrate the management challenges of these coincident diagnosis. In one case, the accompanying coarctation was suspected and required precannulation angiography for confirmation, whereas in the other case, the diagnosis of coarctation was not made until after ECMO cannulation. Depending on its anatomic location and severity, an aortic coarctation associated with life-threatening CDH may limit the physiological efficacy of venoarterial ECMO. Furthermore, arterial cannulation for extracorporeal support requires that flow through the remaining carotid artery be maintained during aortic reconstruction, which may prove difficult for lesions best treated by subclavian flap angioplasty. When the diagnosis of coincident aortic coarctation and CDH is suspected or proven before institution of extracorporeal support, serious consideration should be given to venovenous bypass, because this may provide better postductal oxygenation and facilitate aortic repair with the option of left carotid artery inflow occlusion.

Reconstruction of a severely atrophic maxilla using a Le Fort I downgraft and dental implants: clinical report

A 55-year-old woman developed chronic infections of the maxillary sinuses with osteomyelitis resulting in extensive bone destruction and atrophy from a failed subperiosteal implant. After surgical removal of the subperiosteal implant, extensive debridement of the maxilla, and long-term antibiotic therapy, maxillary reconstruction was initiated. A Le Fort I osteotomy and downgraft was performed, and a posterior iliac bone graft was harvested and grafted to reconstruct the severely atrophic maxilla. In a later surgical procedure, maxillary and mandibular implants were placed. Implant-retained overdentures were fabricated to restore function and esthetics.

A comparison of outcome criteria in the diagnosis of renovascular hypertension

The outcome criteria used for the diagnosis of renovascular hypertension (RVHT) following renal revascularization have not been validated. Differing criteria of indeterminate accuracy have yielded conflicting conclusions concerning the prevalence and efficacy of treatment of RVHT. We compared the accuracy of conventional outcome criteria used in the diagnosis of RVHT to that of novel, ordered outcome analysis to determine whether such an analysis might provide a more consistent means of diagnosing RVHT. Twenty-seven patients underwent intervention for treatment of presumed RVHT (group I), and 40 patients with presumed essential hypertension were treated with antihypertensive medication alone (group II). A standard dichotomized (improved or unimproved) outcome scheme and a five-level, ordered outcome scheme (ranging from definitely unimproved to definitely improved) were used to generate nominal outcomes of therapy for each patient. The resultant outcome groups were examined to determine the effect of such partitioning on blood pressure and medication requirements. To determine their diagnostic accuracy, the conventional and ordered outcome schemes were compared with a consensus outcome scheme derived from the use of numerous criteria. Significant correlations were observed between the ordered outcome score and posttreatment reductions in systolic blood pressure (r = 0.53, p = 0.007), diastolic blood pressure (r = 0.74, p = 0.0001), and medication score (r = 0.71, p = 0.0001). Overall diagnostic accuracy was estimated to be 91% for ordered criteria and 85% for dichotomized criteria. Correlation of the ordered and conventional schemes' assignments with the consensus scheme's assignments was 0.79 (p = 0.0001) and 0.63 (p = 0.0001), respectively. A simple, ordered outcome scheme compares favorably with the standard dichotomized scheme in assigning a diagnosis of RVHT to patients following renal revascularization or nephrectomy. The ordered scheme offers the advantages of simplicity and accuracy over current schemes.

Transcutaneous oxygen measurements predict healing of leg wounds with hyperbaric therapy

Twenty-six patients with chronic leg wounds had transcutaneous oxygen measurements taken from the peri-wound area and a chest reference site before undergoing hyperbaric oxygen therapy in order to evaluate the utility of transcutaneous oxygen measurements in predicting the response of wounds to hyperbaric therapy. Wound scores and wound areas were determined before treatment and after 10 hyperbaric exposures. Patients whose wounds averaged a 5% or greater reduction in wound score per treatment were designated "responders." Nine patients' wounds exhibited at least a 5% reduction in wound score per treatment. There were no differences observed between responders and the 17 nonresponders in age, duration of the wound, initial wound area, initial wound score, or in wound or reference transcutaneous oxygen measurements. Responders required significantly fewer treatments to achieve wound closure than did nonresponders. Peri-wound transcutaneous oxygen pressure when the patient was exposed to 2.4 atmospheres absolute correlated directly with the improvement in wound score per treatment (r = 0.64, p = 0.03). An inverse correlation was noted between surface peri-wound transcutaneous oxygen pressure and improvement in wound score per treatment (r = -0.74, p = 0.006). Elevated peri-wound transcutaneous oxygen measurements at 2.4 atmospheres absolute and reduced peri-wound oxygen measurements at 1 atmosphere absolute were associated with a more rapid response to hyperbaric oxygen treatments in patients with chronic leg wounds. The use of these measurements should allow this expensive and time-consuming therapy to be limited to those patients most likely to benefit.

Acute cholecystitis and cholangitis caused by Echinococcus granulosus

We report for the first time in the recent North American literature, the case of a patient with rupture of a hepatic hydatid cyst into the gallbladder, with subsequent obstruction of the cystic duct by a daughter cyst acting as a ball-valve and causing acute acalculous cholecystitis.

Sequence-selective carbohydrate-DNA interaction: dimeric and monomeric forms of the calicheamicin oligosaccharide interfere with transcription factor function

The synthetic oligosaccharide moiety of the antibiotic calicheamicin and the head-to-head dimer of this oligosaccharide are known to bind to the minor groove of DNA in a sequence-selective manner preferring distinct target sequences. We tested these carbohydrates for their ability to interfere with transcription factor function. The oligosaccharides inhibit binding of transcription factors to DNA in a sequence-selective manner, probably by inducing a conformational change in DNA structure. They also interfere with transcription by polymerase II in vitro. The effective concentrations of the oligosaccharides for inhibition of transcription factor binding and for transcriptional inhibition are in the micromolar range. The dimer is a significantly more active inhibitor than is the monomer.

Factors influencing limb salvage and survival after amputation and revascularization in patients with end-stage renal disease

BACKGROUND

Critical lower-extremity ischemia in patients with end-stage renal disease is associated with high operative mortality and low rates of limb salvage.

PATIENTS AND METHODS

The outcomes of 102 operations for lower-extremity ischemia in 77 patients with end-stage renal disease were analyzed to determine predictors of limb salvage and operative survival.

RESULTS

Patients undergoing amputation (n = 50) and revascularization (n = 52) were similar in age, cause, and duration of renal failure, and prevalence of coronary artery disease. Operative mortality was 13% in revascularized patients and 20% in amputated patients, and was caused by sepsis in 12 of the 17 deaths (71%). Limb salvage in surviving patients was 91% at 30 days and 67% at 1 year. One-year survival was 72% in both groups. Factors associated with limb loss included advanced generalized atherosclerosis, extensive tissue necrosis, failed ipsilateral bypass, and poor cardiac functional status. Overall, factors associated with mortality included failure of limb salvage procedures, hemodynamic instability, and poor cardiac functional status.

CONCLUSIONS

More liberal use of primary amputation for end-stage renal disease patients with critical leg ischemia appears to be an important factor in improving both limb salvage rates and overall operative mortality.

Lesch-Nyhan syndrome. A case report

Lesch-Nyhan syndrome is a rare anomaly consisting of a deficiency in the production of hypoxanthine phosphoribosyltransferase that leads to the overproduction of purine and the accumulation of uric acid. Major manifestations include mental retardation and self-destructive behavior resulting in self-mutilation through biting and scratching. Because no medical treatment exists to alleviate the symptoms of self-mutilation, direct dental intervention is the only way these behaviors can be affected. A unique case of this type involving two male identical twins is reported.

Laparoscopic splenectomy in childhood

The authors describe their technique for laparoscopic splenectomy in childhood. Five ports, including one 12-mm port for an endoscopic stapler, are placed. With the patient in the supine position, the short gastric vessels are divided between clips. The patient is then placed in the lateral decubitus position for mobilization of the splenic flexure of the colon, division of the posterolateral ligamentous attachments, and en masse transection of the splenic hilum using the EndoGIA stapler. The freed spleen is placed in a nylon reinforced Lap Sac, which is exteriorized at the neck. The spleen is morcellated and the sac removed. Concomitant cholecystectomy is performed in patients with hereditary spherocytosis who have cholelithiasis or sludge. The procedure has been performed without complication in six patients who had hematologic disorders. For another patient, the procedure was converted to an open splenectomy to achieve better hemostasis.

Laparoscopic Duhamel pullthrough procedure for Hirschsprung's disease in childhood

Advances in instrumentation and technique now make laparoscopic correction of some congenital anomalies possible. We report on a 2-year-old boy with biopsy-proven Hirschsprung's disease successfully treated by a laparoscopic Duhamel pullthrough procedure. The technique and its potential role in the treatment of Hirschsprung's disease are described.

Health benefits and practical aspects of high-fiber diets

Over the past 20 y dietary fiber has emerged as a leading dietary factor in the prevention and treatment of chronic diseases. High fiber intakes are associated with lower serum cholesterol concentrations, lower risk of coronary heart disease, reduced blood pressure, enhanced weight control, better glycemic control, reduced risk of certain forms of cancer, and improved gastrointestinal function. Dietary fiber can be categorized into water-soluble and water-insoluble components. Dried beans, oat products, and certain fruits and vegetables are good sources of soluble fiber. Most plant foods are good sources of insoluble fiber and wheat bran is a concentrated form of insoluble fiber. Current guidelines advise a doubling of dietary fiber intake for Americans. Inclusion of ample servings of fruits and vegetables, whole grains, and dried beans and peas will help individuals meet these guidelines.

Nonpenetrating trauma to the carotid artery: seven cases and a literature review

Nonpenetrating carotid trauma is uncommon and frequently missed on initial examination. The cases of seven patients seen over a period of 21 years are presented and 100 cases from the most recent literature are reviewed. Causes and mechanisms of injury, clinical presentation, investigations, management, and outcome are discussed. Causes of injury were three motor vehicle collisions, two falls, one sports injury, and one blow to the face. Clinical presentation was early in four and delayed in three. The earliest symptoms and signs were a change in mental status, headache, unprovoked fall, focal weakness, neglect, and dysphasia. Doppler studies may be useful in screening, but a definitive diagnosis is made with the help of angiography. Two patients were treated surgically; one died, one with delayed symptoms from a pseudoaneurysm recovered completely. Five patients were given anticoagulants; all survived with permanent deficits related to their pretreatment neurologic status. The outcome in 100 recent cases from the literature has improved compared with previous reports. The overall mortality was 12%. The outcome in our seven cases supports recent trends toward a strategy of early anticoagulation and selective surgical treatment.

Laparoscopic splenectomy

Splenectomy is easily amenable to laparoscopic technique. Compared with the open technique, its advantages include improved exposure, decreased pain, improved pulmonary function, shortened hospitalization, rapid return to unrestricted activities, and improved cosmetic appearance. These advantages are at the expense of prolonged operative time that, with experience and improved instruments, should diminish.

The lost needle: a laparoscopic dilemma

A case is presented in which a curved needle became lost during extracorporeal suturing in laparoscopic surgery. Maneuvers to find the needle were fruitless until an intraoperative x-ray showed it was stuck in the flapper mechanism of a laparoscopic cannula. Caution is given against the use of "pop-off" needles during extracorporeal suturing and an x-ray of cannulae is suggested when a lost needle cannot be found using routine maneuvers.

Use of auricular cartilage in the repair of orbital floor defects

Various materials have been used to repair orbital defects. This article advocates the use of autogenous conchal cartilage, especially in the repair of large posttraumatic defects, where contour, biocompatibility, and strength are most important. The technique for harvesting the cartilage is reviewed, and a case demonstrating its successful use is reported.

Prospective, randomized, controlled comparison of the effects of low-fat and low-fat plus high-fiber diets on serum lipid concentrations

Previous studies examining the hypocholesterolemic effects of high-soluble-fiber diets have not been designed to control for dietary fat intake. Serum cholesterol reductions may therefore be accounted for by differences in consumption of fat. Moderately hypercholesterolemic, nonobese, Caucasian men and women, 30-50 y old were randomly assigned to low-fat, low-fat plus high-fiber, or usual-diet groups and followed for 12 mo. At 12 mo the high-fiber group consumed significantly more soluble fiber than both the low-fat and usual-diet groups (P = 0.0063 and P = 0.0001); the high-fiber group did not differ from the low-fat group in quantity of dietary fat consumed. The high-fiber group experienced a greater average reduction (13%) in serum cholesterol than did the low-fat (9%) and usual-diet (7%) groups. After adjustment for relevant covariates, the reduction in the high-fiber group was significantly greater than that in the low-fat group (P = 0.0482). Supplementation with soluble fiber reduces serum cholesterol beyond the reduction observed with low-fat diet alone.

Back school programs. The ballet dancer

This article discusses factors influencing back injury in ballet dancers and describes a back rehabilitation program. This program, which applies principles of motor skill acquisition in a progressive manner, has been modified for the young ballet dancer to incorporate aspects of dance class.

Familial biliary atresia in three siblings including twins

We report a North American Indian family of five children in which dizygotic twin sisters and a third sibling had biliary atresia. This is in contrast to many reports of discordant biliary atresia in twins. Added to 29 previously documented cases of familial biliary atresia, these three cases support the theory that both genetic and acquired factors play a role in the pathogenesis of this disease.

Popliteal aneurysm with spontaneous arteriovenous fistula

This report documents a rare manifestation of aneurysmal disease of the popliteal artery. We describe a popliteal aneurysm presenting with acute venous hypertension due to a spontaneously occurring arteriovenous fistula. The fistula was defunctionalized by treating the aneurysm with a standard technique of exclusion and bypass with resolution of the symptoms of venous hypertension and maintenance of normal distal perfusion.