Clinical experience with two physiologic bicarbonate/lactate peritoneal dialysis solutions in automated peritoneal dialysis

Clinical experience with two physiologic bicarbonate/lactate peritoneal dialysis solutions in automated peritoneal dialysis. BACKGROUND: Patients on automated peritoneal dialysis (APD) usually receive larger volumes of dialysis solution and more frequent, shorter exchanges than patients on continuous ambulatory peritoneal dialysis (CAPD), and therefore are likely to derive greater benefit from more physiologic solutions. METHODS: Peritoneal dialysis solutions containing 25 mmol/L bicarbonate and either 10 or 15 mmol/L lactate were compared with standard lactate solutions (35 or 40 mmol/L) in two prospective, open-label studies of patients on APD. Each study included a 2-week baseline period (lactate solution), a 6-week treatment period (bicarbonate/lactate solution), and a 2-week follow-up period (same lactate solution as baseline). Biochemical analyses and assessments of vital signs and safety parameters were conducted at baseline, every 2 weeks during treatment, and at the end of the follow-up period. A product use questionnaire was administered in one study at the end of treatment. RESULTS: A statistically significant rise in plasma bicarbonate (approximately 2 mmol/L) occurred when patients switched from a lactate solution to the bicarbonate/lactate solution with equimolar buffer concentration (P < 0.001 for each solution). Plasma bicarbonate decreased by 1.16 mmol/L after a switch from lactate 40 mmol/L to bicarbonate/lactate 35 mmol/L (P < 0.001). When patients switched to bicarbonate/lactate 35, the majority of individual venous plasma bicarbonate values were in the normal range. A switch from a lower calcium (1.25 mmol/ L) lactate solution to a higher calcium (1.75 mmol/L) lactate/bicarbonate solution resulted in a statistically significant rise in serum calcium (0.06 mmol/L, P < 0.018). The product use questionnaire revealed improvements in symptoms, including reduced pain on infusion. CONCLUSION: Bicarbonate/lactate solutions may be used safely and effectively in patients on APD. The availability of 2 formulations with different buffer and calcium content provides flexibility for the control of acidosis as well as calcium balance.     

Prognosis and possibilities of treatment of inaugural metastases

Prognosis depending on clinical presentation The prognosis of carcinomas of unknown primary site (CUP) is poor, with median survival of 8 months. Prognosis is better for specific clinical forms. Recent predictive models rely on the general status of the patient and simple biological parameters (lacticodehydrogenase or alkaline phosphatase levels) refine the prognostic assessment of CUP except in certain specific clinical forms. Treatment of specific clinical forms Cervical node metastases revealing an unfound epidermoid carcinoma require surgical node excision and radiotherapy. Axillary node metastases in woman require lymph node excision and systemic adjuvant therapy, similar to that used in breast cancer. The management of peritoneal serous papillary carcinomatosis in women consists in chemotherapy as in ovarian cancer, combined with debulking surgery. Median line syndrome requires radiotherapy or chemotherapy (with a cisplatin-etoposide combination or the regimen used for treatment of germ-cell tumours). Other therapeutic possibilities Excluding these forms, no chemotherapy regimen is a gold standard. Best supportive care is an acceptable option. There is little data on locoregional treatments.     

Secundum ASD closure using a right lateral minithoracotomy: five-year experience in 122 patients

BACKGROUND: Surgical closure of secundum atrial septal defect (ASD) is a standard procedure associated with very low mortality and morbidity. We evaluated outcomes in the era of catheter-based interventional closure and minimally invasive techniques. METHODS: From May 1996, February 2002, 177 patients with a body weight of more than 30 kg underwent surgical ASD closure. A right lateral minithoracotomy (LMT) was used in 122 patients and a conventional approach, in 55. Diagnoses included secundum ASD in 106 patients in the LMT group and 40 in the conventional group, sinus venosus ASD in 13 patients in each group, and status post interventional closure in 3 and 2 patients, respectively. Mean age was 37 +/- 17 years in the LMT group and 43 +/- 20 years, in the conventional group and mean body weight was 66 +/- 17 kg and 70 +/- 16 kg, respectively. In the LMT group, femoral cannulation was performed for cardiopulmonary bypass. RESULTS: Direct ASD closure was carried out in 67.2% of patients in the LMT group and 58.2% of those in the conventional group. The remaining patients had pericardial patch closure. There was one death: A patient in the conventional group who required explantation of an Amplatzer device because of infection died postoperatively. Average stay in the intensive care unit was 1.2 +/- 0.5 days. Two patients required reoperation for residual ASD after direct closure; 1 sustained a temporary neurological deficit that resolved completely. On postoperative echocardiography, a minimal residual shunt was seen in only 3 patients. All patients were in good clinical condition with improved functional status at discharge from the hospital. CONCLUSIONS: Secundum ASD closure by LMT has become as standard and safe an operation as the conventional technique and achieves good perioperative results and satisfactory long-term outcomes. Thus LMT is an attractive option for patients who are not suitable for closure using catheter-based devices.     

Intraoperative left atrial ablation (for atrial fibrillation) using a new argon cryocatheter: early clinical experience

PURPOSE: Recently surgical treatment of atrial fibrillation has gained more popularity and presently is being performed in large numbers of patients. This report describes our early experience in treatment of patients with chronic or paroxysmal atrial fibrillation with a new tool for left atrial cryoablation. DESCRIPTION: From July 2002 through January 2003, 28 patients underwent left atrial cryoablation with the Surgifrost CryoCath. Patients underwent cryotherapy as an isolated procedure (n = 1), in combination with mitral valve surgery (n = 13), or with other surgical procedures (n = 14). In all patients contiguous lesion lines to the orifices of the pulmonary veins connected to the mitral annulus and the atriotomy were created. Surgery was performed through a conventional sternotomy in 8 patients (29%) and a right lateral minithoracotomy using video-assistance in 20 patients (71%). EVALUATION: Postoperatively sinus rhythm was restored in 27 patients (96%). At discharge 82% (23/28) of patients were in sinus rhythm and 18% (5/28) were in atrial fibrillation. Four patients (14%) required pacemaker implantation. There was no in-hospital mortality. At 6-months follow-up (19/28 patients) all were alive and 74% were in stable sinus rhythm, New York Heart Association functional class was 1.2 +/- 0.4. CONCLUSIONS: As indicated by our small and early patient cohort left atrial cryoablation with the Surgifrost argon cryocatheter is effective for the treatment of atrial fibrillation. This new device is technically easy to handle, it can be applied through a median sternotomy or lateral minithoracotomy. Long-term follow-up is necessary to evaluate further rhythm outcome.     

Suboptimal restraint affects the pattern of abdominal injuries in children involved in motor vehicle crashes

Background

Both solid and hollow visceral abdominal injuries have been associated with the use of seat belts in children involved in motor vehicle crashes. The relationship between the types of restraint used and the pattern of abdominal injury is unknown.

Methods

A probability sample of restrained children involved in crashes was enrolled in an ongoing crash surveillance system (1998 through 2002) linking insurance claims data to telephone survey and crash investigation data. Significant abdominal injuries were considered when the Abbreviated Injury Scale (AIS) score was ≥2 and were defined as hollow visceral (HV; intestine, bladder), or solid visceral (liver, spleen, pancreas, kidney). Restraint type was categorized as optimal restraint (OR) or suboptimal restraint (S-OR) based on the child’s age and size.

Results

For the 33 months of review, interviews were obtained for 13,558 restrained children aged 0 to 15 years, of which, 56% were OR (n = 7,591) and 44% were S-OR (n = 5,967). A significant abdominal injury was recorded in 78 children. A hollow visceral injury was recorded in 38 (9 OR and 29 S-OR), and a solid visceral injury in 32 (18 OR and 14 S-OR). Both hollow and solid visceral injuries were present in 8 children (2 OR and 6 S-OR). Suboptimally restrained children had a higher risk for hollow visceral injury when compared with optimally restrained children (Odds Ratio, 4.14 [95% Confidence Interval 1.33 to 13.22, P < .01]).

Conclusions

Among restrained children with intraabdominal injuries, those who were suboptimally restrained were 4 times more likely to have a hollow visceral than a solid visceral injury when compared with those who were optimally restrained. This suggests that the mechanism of injury for hollow viscus may be directly related to the improper positioning of the restraint.     

Development of antidepressant drugs. Experience and prospects

THE FIRST ROUTES OF RESEARCH: The first antidepressants were developed after the discovery of the existence during depression of a perturbation in the synaptic transmission of the principle monoamines: noradrenalin, serotonin and dopamine. The pharmacological effect of the various molecules developed is mainly on the metabolisation routes of neurotransmitters, but may also concern the different receptors present on synaptic level. THE AWARENESS OF NEW MEDIATORS: The progress in research on antidepressants has widened the scope of the development of such medicinal products to the domain of endocrinology (hypothalamo-pituitary-adrenal axis, progestogen hormones, thyreotropic axis) and studies on neuropeptides (substance P, neuropeptide Y). The complexity of the physiopathological mechanisms of depression hence appears enhanced.     

Toxicovigilance: new biochemical tool used in sulfonylurea herbicides toxicology studies

In vitro toxic effects of sulfonylurea herbicides (thifensulfuron-methyl and metsulfuron-methyl) were evaluated according to a new protocol. Physiological conditions were reproduced in order to boost toxicovigilance. Sulfonylureas and their hydrolysis products were added to biological substrates such as urea, alanine, aspartic acid, alpha-ketoglutarate, oxaloacetate, pyruvate and then incubated with some specific enzymes. Addition of these sulfonylureas and their degradation products did not significantly change the enzymatic activity of the urease, aspartate-aminotransferase, glutamate dehydrogenase, malate dehydrogenase and lactate dehydrogenase. However, the acid hydrolysis products inhibited up to 95% of the activity of the alanine-aminotransferase at low concentrations (0.27 micromol L(-1)). Inhibition did not affect the mitochondrial aspartate-aminotransferase.     

Metformin and its liver targets in the treatment of type 2 diabetes

Although a number of assessments disagree, the preponderance of the evidence indicates that the major therapeutic action of metformin in type 2 diabetes (DM2) is on the liver, and glucose production (EGP) in particular. At the level of this organ, the actions of metformin can be characterized as pleiotropic. The major questions addressed here are therefore: (i) the methodological aspects of the determination of glucose fluxes: when glucose production is not found to be elevated in type 2 diabetes, it is not surprising that little action of metformin on this flux is found. The issues of populations examined, experimental protocols, and quantitative methods of flux determination are important in answering this question. Early morning EGP is increased and constitutes a valid target for metformin. (ii) the multiple targets of metformin: metformin acts at a number of sites and interacts with metabolites and hormones. Some of these actions may be expressed at different doses. Although their net effect is therapeutic, not all are oriented towards lowering hyperglycemia, perhaps explaining the more modest effect of this drug than could be anticipated from individual actions. Sites of metformin action can therefore be considered as a compilation of valid therapeutic targets in DM2. Gluconeogenesis, glycogenolysis and glycogen synthesis can be altered by metformin, although in vivo, this also depends on the methodology. Component processes from substrate supply and liver uptake, through a number of glucogenic enzymes, as well as glycogen synthase and phosphorylase have all been shown to be affected. (iii) unifying concepts: reported actions of metformin on the mitochondrial respiratory chain, free fatty acid metabolism, AMP-activated protein kinase, and on membrane proteins directly may all explain subsets of actions that are seen, providing more integrated targets for consideration in the therapy of DM2.