Outcome of renal transplants from pediatric donors <5 yr of age

AIM: Outcomes of single renal transplants from donors <5 yr old have traditionally been inferior to those from older donors. We retrospectively studied our experience with patients who received renal transplants, either individually or en bloc, from young donors (<5 yr of age) to determine the utility of these organs. We also compared the outcomes of these transplant patients maintained on either cyclosporine- (CyA) or tacrolimus-based (TRL) immunosuppression regimens. PATIENTS: Ninety-eight patients received transplants at our center from donors <5 yr of age between August 1993 and August 2003. They were followed-up from 12 months to 11 yr. Patients were divided into four groups based on whether they received single or en bloc transplants, and whether CyA or TRL was the base immunosuppressive agent. Patients in group I (n = 13) received single pediatric kidneys and were treated with CyA regimens; group II patients (n = 26) also received single pediatric kidneys, but were treated with TRL regimens; group III patients (n = 31) were transplanted en bloc and were treated with CyA; and group IV patients (n = 28) received en bloc transplants and were treated with TRL. RESULTS: One-year patient and death-censored graft survival was not significantly different between recipients of en bloc vs. single grafts (i.e. 88 and 85% vs. 90 and 87%, respectively), or between the four treatment groups (group I: 85 and 85%, group II: 92 and 88%, group III: 87 and 84%, and group IV: 89 and 86%, respectively). The overall 1-yr rejection rate was 30% (29 of 98), which was significantly higher in the CyA-treated patients 19 of 44; i.e. 43%, than in TRL-treated patients 10 of 54, i.e. 19%, p = 0.03). In the en bloc recipients, seven grafts (12%) were lost as a result of vascular thrombosis. Notably, none of the single kidneys were lost because of vascular thrombosis. At the end of follow-up the creatinine levels of both groups were comparable. CONCLUSIONS: Pediatric donor kidneys transplanted individually provide for equal patient and graft survival when compared with en bloc transplants. TRL can be used reduce the detrimental effect of acute rejection on graft growth and function when compared with CyA. Single use of such kidneys can safely and efficaciously be transplanted into adult recipients, greatly expanding the donor pool.     

Perioperative N-acetylcysteine to prevent renal dysfunction in high-risk patients undergoing cabg surgery: a randomized controlled trial

Context  Renal dysfunction is a complication of coronary artery bypass graft (CABG) surgery performed with cardiopulmonary bypass (CPB) that is associated with increased morbidity and mortality. N-acetylcysteine, an antioxidant and vasodilator, counteracts renal ischemia and hypoxia. Objective  To determine whether perioperative intravenous (IV) N-acetylcysteine preserves renal function in high-risk patients undergoing CABG surgery with CPB compared with placebo. Design, Setting, and Patients  Randomized, quadruple blind, placebo-controlled trial (October 2003-September 2004) in operating rooms and general intensive care units (ICUs) of 2 Ontario tertiary care centers. The 295 patients required elective or urgent CABG and had at least 1 of the following: preexisting renal dysfunction, at least 70 years old, diabetes mellitus, impaired left ventricular function, or undergoing concomitant valve or redo surgery. Interventions  Patients received 4 (2 intraoperative and 2 postoperative) doses of IV N-acetylcysteine (600 mg) (n = 148) or placebo (n = 147) over 24 hours. Main Outcome Measures  The primary outcome was the proportion of patients developing postoperative renal dysfunction, defined by an increase in serum creatinine level greater than 0.5 mg/dL (44 µmol/L) or a 25% increase from baseline within the first 5 postoperative days. Secondary outcomes included postoperative interventions and complications, the requirement for renal replacement therapy (RRT), adverse events, hospital mortality, and ICU and hospital length of stay. Results  There was no difference in the proportion of patients with postoperative renal dysfunction (29.7% vs 29.0%, P = .89; relative risk [RR], 1.03 [95% confidence interval {CI}, 0.72-1.46]) in the N-acetylcysteine and placebo groups, respectively. We noted nonsignificant differences in postoperative interventions and complications, the need for RRT (0.7% vs 2.1%; P = .37), total (6.1% vs 9.6%; P = .26) and serious adverse events, hospital mortality (3.4% vs 2.7%; P>.99), and ICU and hospital length of stay between the N-acetylcysteine and placebo groups. A post hoc subgroup analysis of patients (baseline creatinine level >1.4 mg/dL [120 µmol/L]) showed a nonsignificant trend toward fewer patients experiencing postoperative renal dysfunction in the N-acetylcysteine group compared with the placebo group (25.0% vs 37.1%; P = .29). Conclusions  N-acetylcysteine did not prevent postoperative renal dysfunction, interventions, complications, or mortality in high-risk patients undergoing CABG surgery with CPB. Further research is required to identify CABG patients at risk for postoperative renal events, valid markers of renal dysfunction, and to establish renal thresholds associated with important clinical outcomes.      

An exploration into the most effective way to teach drug calculation skills to nursing students

Drug calculations are an essential skill for nurses. Nurses need to be able to perform them accurately to calculate correct dosages of drugs to administer to patients. Incorrect calculations can cause drug errors and potential harm to patients (; ). For student nurses therefore learning how to calculate drug dosages is an important skill that they need to be taught during their nurse training. This paper describes an action research project undertaken to explore the most effective way of teaching drug calculations to a group if 2nd year diploma and degree pre registration nurses. The evaluation of this project has demonstrated that a three stage approach to drug calculation appears to be an effective teaching strategy. These stages involve addressing mathematical concepts, teaching drug calculation formulae and then practising these skills in a clinical setting.     

Dexmedetomidine pharmacodynamics: part I: crossover comparison of the respiratory effects of dexmedetomidine and remifentanil in healthy volunteers

BACKGROUND: Dexmedetomidine, a highly selective alpha2-adrenoceptor agonist used for short-term sedation of mechanically ventilated patients, has minimal effect on ventilation. METHODS: This study compared the respiratory effect of dexmedetomidine to that of remifentanil. The authors measured and compared respiratory responses of six healthy male volunteers during (1) a stepwise target-controlled infusion of remifentanil, (2) a stepwise target-controlled infusion of dexmedetomidine, and (3) a pseudonatural sleep session. RESULTS: Compared with baseline, remifentanil infusions resulted in respiratory depression as evidenced by a decrease in respiratory rate and minute ventilation, respiratory acidosis, and apnea episodes resulting in desaturations. Remifentanil disturbed the natural pattern of breathing and flattened the distribution of ventilatory timing (inspiratory time/ventilatory cycle time). The respiratory effects of dexmedetomidine markedly contrasted with those of remifentanil. When compared with baseline, during dexmedetomidine infusions, the respiratory rate significantly increased, and the overall apnea/hypopnea index significantly decreased. The distribution of inspiratory time/ventilatory cycle time showed an increased peak. In addition, dexmedetomidine seemed to mimic some aspect of natural sleep. While the subjects were breathing a 5% CO2 mixture, hypercapnic arousal phenomena (documented by the Bispectral Index, the electroencephalogram, and sudden increase in the minute ventilation) were observed during dexmedetomidine infusions. Similar phenomena during natural sleep have been reported in the literature. CONCLUSIONS: In comparison with remifentanil, dexmedetomidine infusions (1) did not result in clinically significant respiratory depression, (2) decreased rather than increased the apnea/hypopnea index, and (3) exhibited some similarity with natural sleep.     

An effective pyloromyotomy length in infants undergoing laparoscopic pyloromyotomy

BACKGROUND: Traditional management of pyloric stenosis has consisted of open pyloromyotomy during which the surgeon is able to palpate and determine whether the hypertrophied pylorus has been completely divided. During the last decade, laparoscopic pyloromyotomy has become an increasingly popular approach for this condition. The purpose of this study was to determine whether there is an effective pyloromyotomy length that will allow the surgeon to feel confident that a complete pyloromyotomy was performed with the laparoscopic approach. METHODS: All infants undergoing laparoscopic pyloromyotomy from October 1999 through October 2003 at a single institution were retrospectively studied. Clinical variables collected included the patient's age, gender, electrolyte status on admission, the elapsed time from admission to operation, ultrasonographic dimensions of the hypertrophied pylorus, operative time, the length of the pyloromyotomy performed, the time to initial and to full feedings, and the duration of the postoperative hospitalization. RESULTS: One hundred seventy-one patients comprised the study group. The age (mean +/- standard deviation) at the time of operation was 5.2 +/- 2.8 weeks. The mean preoperative ultrasonic measurements for both pyloric thickness and pyloric length were 4.3 +/- 0.7 mm and 19.5 +/- 2.8 mm, respectively. The average pyloromyotomy incision length for this entire group was 1.9 +/- 0.21 cm. The mean operative time was 23.5 +/- 8.3 minutes. There were no mucosal perforations, no conversions to an open procedure, and no evidence for an incomplete pyloromyotomy. CONCLUSIONS: Laparoscopic pyloromyotomy is a safe and effective technique for infants with pyloric stenosis. A pyloromyotomy incision length of approximately 2 cm appears to be an effective measure of a complete pyloromyotomy.     

Comparison of heparin administration using the Rapidpoint Coag and Hepcon HMS

A retrospective chart review was conducted of patients who underwent cardiopulmonary bypass (CPB) to compare the quantities of heparin administered, postoperative blood loss, and homologous blood products transfused during their procedure and subsequent stay in the intensive care unit. The primary purpose of this review was to determine if any difference in heparin administration resulted when two different devices were used for dosing and monitoring heparin. Postoperative blood loss and amount of blood products transfused were also quantified, as any differences would potentially be a result of a difference in administration of heparin. The first group (n = 341) underwent CPB using the Hepcon HMS, Medtronic Inc., Minneapolis, MN, for heparin dosing and monitoring. The Rapid Point Coag, Bayer Healthcare LLC, Tarrytown, NY was used for the second group (n = 345). The two populations were compared for similarity on: age, body surface area (BSA), CPB time (minutes), aortic-cross clamp time (minutes), baseline activated clotting time, and baseline hematocrit. No significant difference was found between the two groups. The second group, using the Rapidpoint Coag, received less heparin during CPB than the group using the Hepcon HMS. In addition, there were decreases in amounts of some blood products transfused as well as mediastinal drainage from the Hepcon HMS to the Rapidpoint Coag group. A summary of the findings can be found in Table 1. A secondary purpose of this study was to determine the influence of hemodilution on the Heparin Management Test (HMT). Citrated whole blood was diluted to varying degrees at various concentrations to determine whether hemodilution with crystalloid would alter the HMT measurements. At all heparin levels and degrees of dilution, the HMT remained stable, with coefficients of variation (CV) of less than 5% at all heparin levels even while incorporating excessive crystalloid dilution (up to 75%).     

Musculoskeletal response to exercise is greatest in women with low initial values

INTRODUCTION: The "initial values" principle of exercise training states those with the lowest initial values of a physiologic system have the greatest capacity for improvement in response to training. We sought to determine whether initial values predicted the musculoskeletal response to training in premenopausal women (N = 31) who participated in a 1-yr program of resistance and jump training designed to improve physical indices of fracture risk. Significant improvements in trochanteric bone mineral density (BMD), hip abductor strength, power, and postural stability occurred in response to training. METHODS: To determine the predictive power of initial values, we performed separate stepwise regression analyses for each variable including the following dependent variables: age, initial value, highest weight lifted during training, and total number of exercise sessions attended. RESULTS: In each case, the initial value was the most significant predictor of percent change in response to training. Initial values explained 15-29% of the variance in the magnitude of the training response. For each unit lower BMD of the greater trochanter (0.01 g.cm-2), the training response was 12% greater. For each unit decrease in initial strength (1 N.m), power (1 W), and stability (1 SI unit), the training response was 1.0%, 0.2%, and 8.0% greater, respectively. When categorized by quartile of initial values, women in the lowest quartile had two- to fivefold greater improvements in musculoskeletal measures than those in the upper quartile. CONCLUSION: Women who began training with the lowest initial values had the greatest improvements in hip BMD, hip abductor strength, leg power, and postural stability. These results support the training principle of initial values and suggest that this training program may be most successful in premenopausal women with lower values of musculoskeletal indices of fracture risk.     

Food for trans-Atlantic rowers: a menu planning model and case study

Every 4 years, rowers from around the world compete in a 50- to 60-day trans-Atlantic rowing challenge. These ultra-distance rowers require a diet that provides adequate calories, protein, vitamins, minerals, and fluids so they can perform well day after day, minimize fatigue, and stay healthy. Yet, the rowers are confronted with menu planning challenges. The food needs to be lightweight, compact, sturdy, non-spoiling in tropical temperatures, calorie dense, easy to prepare, quick to cook, and good tasting. Financial concerns commonly add another menu planning challenge. The purpose of this case study is to summarize the rowers' food experiences and to provide guidance for sports nutrition professionals who work with ultra-endurance athletes embarking on a physical challenge with similar food requirements. The article provides food and nutrition recommendations as well as practical considerations for ultra-distance athletes. We describe an 8,000 calorie per day menu planning model that uses food exchanges based on familiar, tasty, and reasonably priced supermarket foods that provide the required nutrients and help contain financial costs.