Elevated serum insulin-like growth factor 1 in recurrent aphthous stomatitis.

Over 100 million Americans experience recurrent aphthous stomatitis (RAS) at some point in life. To develop targeted drugs for RAS treatment, it is critical to identify its etiology. We determined if serum insulin-like growth factor 1 (IGF-1) and related factors are associated with RAS, because both RAS prevalence and IGF-1 are highest during puberty. We analyzed data from 1,480 Third National Health and Nutrition Examination Survey participants aged 20-40 years. Participants with a history of diabetes or lupus, cotinine levels 6 ng/ml or higher or glycemia 110 mg/dl or higher were excluded. We compared levels of IGF-1, IGFBP-3, leptin, and insulin in participants with a positive vs. negative RAS history in the prior 12 months. We used logistic regression in SAS/SUDAAN to account for the complex sampling design. The odds of a positive RAS history were 1.31 times higher for every 100 ng/ml increase in serum IGF-1. This association persisted after adjustment for age, race/ethnicity, medication intake, body mass index, insulin, leptin, glycemia, and income (adjusted OR = 1.30, 95% CI [1.06, 1.60]; p = 0.013). The odds of a positive RAS history were also higher among non-Hispanic white compared with non-Hispanic black participants (adjusted OR = 4.37, 95% CI [3.00, 6.38]). Leptin, IGFBP-3, and insulin levels did not differ by RAS status. The significantly higher IGF-1 levels in participants with a positive RAS history compared with controls suggest a possible role of the IGF-1 pathway in RAS etiology.

Verification of association of elevated serum IDO enzyme activity with acute rejection and low CD4-ATP levels with infection.

BACKGROUND: Both acute rejection (AR) and major infection events (MIE) can reduce long-term allograft survival. We assessed the simultaneous efficacy of serum and urine biomarker indoleamine 2,3-dioxygenase (IDO) enzyme activity and peripheral blood CD4-ATP levels for AR and MIE association, respectively. METHODS: We prospectively tested 217 blood and 167 urine serial samples, collected monthly for 12 months after transplantation from 29 consecutive children receiving a kidney transplant. The indoleamine 2,3-dioxygenase activity was assessed by mass spectrometry assays using the ratio of product L-kynurenine (kyn) to substrate tryptophan (trp). Kyn/trp ratios and blood CD4 T-cell ATP levels were correlated with AR, MIE, or stable group (no events) in the next 30 days. RESULTS: Using absolute cutoffs and allocating to samples to AR, MIE, or stable group, mean serum kyn/trp ratios were significantly elevated in the group that experienced AR (P=0.0007). Similarly, peripheral blood CD4-ATP levels were significantly lower in the group experiencing MIE (P=0.0351). Urine kyn/trp ratios and blood tacrolimus levels were not different between AR and stable groups. Within-subject analyses, accounting for repeated measures in subjects, also showed that, over time, serum kyn/trp ratios were higher before AR (P=0.031) and blood CD4-ATP levels were lower before MIE (P=0.008). CONCLUSIONS: These results from our pilot discovery group suggest that a panel of biomarkers together can predict overimmunosuppression or underimmunosuppression. Further independent validation in a multicenter cohort is suggested.

Autologous umbilical cord blood infusion followed by oral docosahexaenoic acid and vitamin D supplementation for C-peptide preservation in children with Type 1 diabetes.

We sought to determine if autologous umbilical cord blood (UCB) infusion followed by 1 year of supplementation with vitamin D and docosahexaenoic acid (DHA) can preserve C-peptide in children with type 1 diabetes. We conducted an open-label, 2:1 randomized study in which 15 type 1 diabetes subjects with stimulated C-peptide > .2 pmol/mL received either (1) autologous UCB infusion, 1 year of daily oral vitamin D (2000 IU), and DHA (38 mg/kg) and intensive diabetes management or (2) intensive diabetes management alone. Primary analyses were performed 1 year after UCB infusion. Treated (N = 10) and control (N = 5) subjects had median ages of 7.2 and 6.6 years, respectively. No severe adverse events were observed. Although the absolute rate of C-peptide decline was slower in treated versus control subjects, intergroup comparisons failed to reach significance (P = .29). Area under the curve C-peptide declined and insulin use increased in both groups (P < .01). Vitamin D levels remained stable in treated subjects but declined in control subjects (P = .01). DHA levels rose in treated subjects versus control subjects (P = .003). CD4/CD8 ratio remained stable in treated subjects but declined in control subjects (P = .03). No changes were seen in regulatory T cell frequency, total CD4 counts, or autoantibody titers. Autologous UCB infusion followed by daily supplementation with vitamin D and DHA was safe but failed to preserve C-peptide. Lack of significance may reflect small sample size. Future efforts will require expansion of specific immunoregulatory cell subsets, optimization of combined immunoregulatory and anti-inflammatory agents, and larger study cohorts.

Validation of anamnestic diagnostic criteria for recurrent aphthous stomatitis.

BACKGROUND: Recurrent aphthous stomatitis (RAS) is characterized by painful recurrent oral ulcers and is typically diagnosed via history and clinical examination. Our aim was to validate a set of anamnestic diagnostic criteria (RASDX) to increase the accuracy of RAS diagnosis, particularly when a clinical examination is not feasible. METHODS: Participants were enrolled during an unmatched case-control study. RASDX consisted of an initial phone screening using standardized questionnaires and recognition of RAS photographs in the clinic. The proportion of agreement with an examination by an oral medicine expert was calculated. RESULTS: A total of 115 participants were scheduled for a clinical diagnostic visit and 11 were withdrawn. The remaining 104 participants were aged 18-50 years, 54% women, 64% White and 20% Hispanic. Of these, all 49 controls with negative RASDX had no clinical ulcers. Of the 54 cases diagnosed with RAS by RASDX, 53 were clinically confirmed to have RAS lesions (99% agreement; exact one-sided 95% CI = 95-100%). CONCLUSIONS: RASDX, based on a combination of history and photograph recognition, was highly accurate compared with a diagnosis that employed an oral examination.

Plasma concentration of N-terminal pro-atrial and N-terminal pro-brain natriuretic peptides and fluid balance in children with bronchiolitis.

The aim of this study was to evaluate the plasma levels of N-Terminal pro-brain natriuretic peptide (N-BNP), N-Terminal pro-atrial natriuretic peptide (N-ANP) and antidiuretic hormone (ADH) over time and their relationship to clinical indicators in hospitalized children with bronchiolitis. Prospective crossover clinical investigation. Hospitalized children in a university-affiliated hospital. Twenty-seven children (birth to 24 mo) with first episode of bronchiolitis and 34 age-matched healthy controls. Daily blood samples up to five consecutive days were obtained for N-BNP, N-ANP and ADH in the bronchiolitis group and on the initial blood draw in the control group. Daily total fluid intake, net fluid balance and clinical bronchiolitis severity levels were recorded. N-BNP and N-ANP levels were measured by enzyme-linked immunosorbent assay. ADH levels were measured by a double antibody technique. The mean age (months ± SD) in the bronchiolitis group was 4.2 ± 5.9 mo and 12.0 ± 6.1 mo in the control group; 51.9% of bronchiolitis patients were positive for respiratory syncytial virus (RSV). In patients with bronchiolitis on admission, plasma N-BNP measurements (mean ± SD) were elevated (996.0 ± 570.2 fmol/mL) compared to controls (552.7 ± 264.7 fmol/mL P < 0.005). Serum N-ANP levels were also initially elevated (3,889 ± 1,769.7 fmol/mL) compared to controls (2,173 ± 912 fmol/mL P < 0.005). The serum levels of N-BNP and N-ANP remained significantly elevated from day 2 through day 5. Similarly, ADH levels were significantly higher on admission in the bronchiolitis group (10 ± 7.49 pg/mL) vs. the control group (5.8 ± 5.5 pg/mL P < 0.05), but quickly decreased from day 2 through day 5. N-BNP, N-ANP and ADH concentrations were elevated in hospitalized children with bronchiolitis at admission. Based on our observation, judicious fluid management is indicated in children hospitalized with bronchiolitis.

Autologous umbilical cord blood transfusion in young children with type 1 diabetes fails to preserve C-peptide.

OBJECTIVE: We conducted an open-label, phase I study using autologous umbilical cord blood (UCB) infusion to ameliorate type 1 diabetes (T1D). Having previously reported on the first 15 patients reaching 1 year of follow-up, herein we report on the complete cohort after 2 years of follow-up. RESEARCH DESIGN AND METHODS: A total of 24 T1D patients (median age 5.1 years) received a single intravenous infusion of autologous UCB cells and underwent metabolic and immunologic assessments. RESULTS: No infusion-related adverse events were observed. ß-Cell function declined after UCB infusion. Area under the curve C-peptide was 24.3% of baseline 1 year postinfusion (P < 0.001) and 2% of baseline 2 years after infusion (P < 0.001). Flow cytometry revealed increased regulatory T cells (Tregs) (P = 0.04) and naive Tregs (P = 0.001) 6 and 9 months after infusion, respectively. CONCLUSIONS: Autologous UCB infusion in children with T1D is safe and induces changes in Treg frequency but fails to preserve C-peptide.

Immune biomarker panel monitoring utilizing IDO enzyme activity and CD4 ATP levels: prediction of acute rejection vs. viral replication events.

Infections have become as important an event as acute rejection posttransplant for long-term allograft survival. Less invasive biomarkers tested so far predict risk for one event or the other, not both. We prospectively tested blood and urine monthly for 12 months posttransplant from children receiving a kidney transplant. The IDO enzyme pathway was assessed by MS assays using the ratio of product l-kyn to substrate trp. Kyn/trp ratios and blood CD4 T-cell ATP levels were correlated with acute rejection or major infection events or stable group (no events) in the next 30 days. The 25 subjects experienced six discrete episodes of acute rejection in five subjects and 16 discrete events of major infection in 14 subjects (seven BK viruria, six cytomegaloviremia, one EB and cytomegaloviremia, and two transplant pyelonephritis). Mean serum kyn/trp ratios were significantly elevated in the group that experienced acute rejection (p = 0.02). Within-subject analyses revealed that over time, urine kyn/trp ratios showed an increase (p = 0.01) and blood CD4-ATP levels showed a decrease (p = 0.007) prior to a major infection event. These pilot results suggest that a panel of biomarkers together can predict over- or under-immunosuppression, but need independent validation.

Long-term pain, stiffness, and functional disability after total knee arthroplasty with and without an extended ambulatory continuous femoral nerve block: a prospective, 1-year follow-up of a multicenter, randomized, triple-masked, placebo-controlled trial.

BACKGROUND: Previously, we have demonstrated that extending a continuous femoral nerve block (cFNB) from overnight to 4 days after total knee arthroplasty (TKA) provides clear benefits during the infusion, but not subsequent to catheter removal. However, there were major limitations in generalizing the results of that investigation, and we subsequently performed a very similar study using a multicenter format, with many health care providers, in patients on general orthopedic wards, thus greatly improving inference of the results to the general population. Not surprisingly, the perioperative/short-term outcomes differed greatly from the first, more limited study. We now present a prospective follow-up study of the previously published, multicenter, randomized controlled clinical trial to investigate the possibility that an extended ambulatory cFNB decreases long-term pain, stiffness, and functional disability after TKA, which greatly improves inference of the results to the general population. METHODS: Subjects undergoing TKA received a cFNB with ropivacaine 0.2% from surgery until the following morning, at which time patients were randomized to continue either perineural ropivacaine (n=28) or normal saline (n=26). Patients were discharged with their catheter and a portable infusion pump, and catheters were removed on postoperative day 4. Health-related quality of life was measured using the Western Ontario and McMaster Universities Osteoarthritis Index preoperatively and then at 7 days, as well as 1, 2, 3, 6, and 12 months after surgery. This index evaluates pain, stiffness, and physical functional disability. For inclusion in the analysis, we required a minimum of 4 of the 6 time points, including day 7 and at least 2 of months 3, 6, and 12. RESULTS: The 2 treatment groups had similar Western Ontario and McMaster Universities Osteoarthritis scores for the mean area-under-the-curve calculations (point estimate for the difference in mean area under the curve for the 2 groups [overnight infusion group - extended infusion group]=3.8; 95% confidence interval, -3.8 to +11.3; P=0.32) and at all individual time points (P>0.05). CONCLUSIONS: This investigation found no evidence that extending an overnight cFNB to 4 days improves (or worsens) subsequent pain, stiffness, or physical function after TKA in patients of multiple centers convalescing on general orthopedic wards.

A multicenter, randomized, triple-masked, placebo-controlled trial of the effect of ambulatory continuous femoral nerve blocks on discharge-readiness following total knee arthroplasty in patients on general orthopaedic wards.

A continuous femoral nerve block (cFNB) involves the percutaneous insertion of a catheter adjacent to the femoral nerve, followed by a local anesthetic infusion, improving analgesia following total knee arthroplasty (TKA). Portable infusion pumps allow infusion continuation following hospital discharge, raising the possibility of decreasing hospitalization duration. We therefore used a multicenter, randomized, triple-masked, placebo-controlled study design to test the primary hypothesis that a 4-day ambulatory cFNB decreases the time until each of three predefined readiness-for-discharge criteria (adequate analgesia, independence from intravenous opioids, and ambulation 30m) are met following TKA compared with an overnight inpatient-only cFNB. Preoperatively, all patients received a cFNB with perineural ropivacaine 0.2% from surgery until the following morning, at which time they were randomized to either continue perineural ropivacaine (n=39) or switch to normal saline (n=38). Patients were discharged with their cFNB and portable infusion pump as early as postoperative day 3. Patients who were given 4 days of perineural ropivacaine attained all three criteria in a median (25th-75th percentiles) of 47 (29-69)h, compared with 62 (45-79)h for those of the control group (Estimated ratio=0.80, 95% confidence interval: 0.66-1.00; p=0.028). Compared with controls, patients randomized to ropivacaine met the discharge criterion for analgesia in 20 (0-38) versus 38 (15-64)h (p=0.009), and intravenous opioid independence in 21 (0-37) versus 33 (11-50)h (p=0.061). We conclude that a 4-day ambulatory cFNB decreases the time to reach three important discharge criteria by an estimated 20% following TKA compared with an overnight cFNB, primarily by improving analgesia.

Two-thumb technique is superior to two-finger technique during lone rescuer infant manikin CPR.

OBJECTIVE: Infant CPR guidelines recommend two-finger chest compression with a lone rescuer and two-thumb with two rescuers. Two-thumb provides better chest compression but is perceived to be associated with increased ventilation hands-off time. We hypothesized that lone rescuer two-thumb CPR is associated with increased ventilation cycle time, decreased ventilation quality and fewer chest compressions compared to two-finger CPR in an infant manikin model. DESIGN: Crossover observational study randomizing 34 healthcare providers to perform 2 min CPR at a compression rate of 100 min(-1) using a 30:2 compression:ventilation ratio comparing two-thumb vs. two-finger techniques. METHODS: A Laerdal Baby ALS Trainer manikin was modified to digitally record compression rate, compression depth and compression pressure and ventilation cycle time (two mouth-to-mouth breaths). Manikin chest rise with breaths was video recorded and later reviewed by two blinded CPR instructors for percent effective breaths. Data (mean+/-SD) were analyzed using a two-tailed paired t-test. Significance was defined qualitatively as p< or =0.05. RESULT: Mean % effective breaths were 90+/-18.6% in two-thumb and 88.9+/-21.1% in two-finger, p=0.65. Mean time (s) to deliver two mouth-to-mouth breaths was 7.6+/-1.6 in two-thumb and 7.0+/-1.5 in two-finger, p<0.0001. Mean delivered compressions per minute were 87+/-11 in two-thumb and 92+/-12 in two-finger, p=0.0005. Two-thumb resulted in significantly higher compression depth and compression pressure compared to the two-finger technique. CONCLUSION: Healthcare providers required 0.6s longer time to deliver two breaths during two-thumb lone rescuer infant CPR, but there was no significant difference in percent effective breaths delivered between the two techniques. Two-thumb CPR had 4 fewer delivered compressions per minute, which may be offset by far more effective compression depth and compression pressure compared to two-finger technique.

Improved chest recoil using an adhesive glove device for active compression-decompression CPR in a pediatric manikin model.

OBJECTIVE: We developed an adhesive glove device (AGD) to perform ACD-CPR in pediatric manikins, hypothesizing that AGD-ACD-CPR provides better chest decompression compared to standard (S)-CPR. DESIGN: Split-plot design randomizing 16 subjects to test four manikin-technique models in a crossover fashion to AGD-ACD-CPR vs. S-CPR. Healthcare providers performed 5min of CPR with 30:2 compression:ventilation ratio in the four manikin models: (1) adolescent; (2) child two-hand; (3) child one-hand; and (4) infant two-thumb. METHODS: Modified manikins recorded compression pressure (CP), compression depth (CD) and decompression depth (DD). The AGD consisted of a modified oven mitt with an adjustable strap; a Velcro patch was sewn to the palmer aspect. The counter Velcro patch was bonded to the anterior chest wall. For infant CPR, the thumbs of two oven mitts were stitched together with Velcro. Subjects were asked to actively pull up during decompression. Subjects' heart rate (HR), respiratory rate (RR) and recovery time (RT) for HR/RR to return to baseline were recorded. Subjects were blinded to data recordings. Data (mean+/-SEM) were analyzed using a two-tailed paired t-test. Significance was defined qualitatively as P< or =0.05. RESULTS: Mean decompression depth difference was significantly greater with AGD-ACD-CPR compared to S-CPR; 38-75% of subjects achieved chest decompression to or beyond baseline. AGD-ACD-CPR provided 6-12% fewer chest compressions/minute than S-CPR group. There was no significant difference in CD, CP, HR, RR and RT within each group comparing both techniques. CONCLUSION: A simple, inexpensive glove device for ACD-CPR improved chest decompression with emphasis on active pull in manikins without excessive rescuer fatigue. The clinical implication of fewer compressions/minute in the AGD group needs to be evaluated.

Early childhood obesity is associated with compromised cerebellar development.

As part of a study investigating commonalities between Prader-Willi syndrome (PWS-a genetic imprinting disorder) and early-onset obesity of unknown etiology (EMO) we measured total cerebral and cerebellar volume on volumetric magnetic resonance imaging (MRI) images. Individuals with PWS (N = 16) and EMO (N = 12) had smaller cerebellar volumes than a control group of 15 siblings (p = .02 control vs. EMO; p = .0005 control vs. PWS), although there was no difference among the groups in cerebral volume. Individuals with PWS and EMO also had impaired cognitive function: general intellectual ability (GIA): PWS 65 +/- 25; EMO 81 +/- 19; and Controls 112 +/- 13 (p < .0001 controls vs. PWS and controls vs. EMO). As both conditions are characterized by early-onset obesity and slowed cognitive development, these results raise the possibility that early childhood obesity retards both cerebellar and cognitive development.

Effect of alternative chest compression techniques in infant and child on rescuer performance.

OBJECTIVE: Current chest compression (CC) guidelines for an infant recommend a two-finger (TF) technique with lone rescuer and a two- thumb (TT) technique with two rescuers, and for a child either an one hand (OH) or a two hand (TH) technique with one or two rescuers. The effect of a 30:2 compression:ventilation ratio using these techniques on CC quality and rescuer fatigue is unknown. We hypothesized that during lone rescuer CC, TT technique, in infant and TH in child achieve better compression depth (CD) without additional rescuer fatigue compared with TF and OH, respectively. DESIGN: Randomized observational study. SETTING: University-affiliated pediatric hospital. SUBJECTS: Adult healthcare providers certified in basic life support or pediatric advanced life support. INTERVENTIONS: Laerdal baby advanced life support trainer and Resusci junior manikin were modified to digitally record CD, compression pressure (CP) and compression rate. Sixteen subjects were randomized to each of the four techniques to perform 5 minutes of lone rescuer 30:2 compression:ventilation cardiopulmonary resuscitation. Rescuer heart rate (HR) and respiratory rate were recorded continuously and the recovery time interval for HR/respiratory rate to return to baseline was determined. Subjects were blinded to data recording. Groups were compared using two-sample, two-sided Student's t tests. MEASUREMENTS AND MAIN RESULTS: Two-thumb technique generated significantly higher CD and peak CP compared with TF (p < 0.001); there was no significant difference between OH vs. TH. TF showed decay of CD and CP over time compared with TT. Compression rate (per minute) and actual compressions delivered were not significantly different between groups. No significant differences in fatigue and recovery time were observed, except the TT group had greater increase in the rescuer's HR (bpm) from baseline compared with TF group (p = 0.04). CONCLUSIONS: Two-thumb compression provides higher CD and CP compared with TF without any evidence of decay in quality and additional rescuer fatigue over 5 minutes. There was no significant difference in child CC quality or rescuer fatigue between OH and TH. Two-thumb technique is preferred for infant CC and our data support the current guidelines for child CC.

Production of 1-carbon units from glycine is extensive in healthy men and women.

Glycine undergoes decarboxylation in the glycine cleavage system (GCS) to yield CO(2), NH(3), and a 1-carbon unit. CO(2) also can be generated from the 2-carbon of glycine by 10-formyltetrahydrofolate-dehydrogenase and, after glycine-to-serine conversion by serine hydroxymethyltransferase, from the tricarboxylic acid cycle. To evaluate the relative fates of glycine carbons in CO(2) generation in healthy volunteers (3 male, 3 female, aged 21-26 y), primed, constant infusions were conducted using 9.26 micromol x h(-1) x kg(-1) of [1,2-(13)C]glycine and 1.87 micromol x h(-1) x kg(-1) of [5,5,5-(2)H(3)]leucine, followed by an infusion protocol using [1-(13)C]glycine as the glycine tracer. The time period between the infusion protocols was >6 mo. In vivo rates of whole-body glycine and leucine flux were nearly identical in protocols with [1,2-(13)C]glycine and [5,5,5-(2)H(3)]leucine and with [1-(13)C]glycine and [5,5,5-(2)H(3)]leucine tracers, which showed high reproducibility between the tracer protocols. Using the [1-(13)C]glycine tracer, breath CO(2) data showed a total rate of glycine decarboxylation of 96 +/- 8 micromol x h(-1) x kg(-1), which was 22 +/- 3% of whole-body glycine flux. In contrast, infusion of [1,2-(13)C]glycine yielded a glycine-to-CO(2) flux of 146 +/- 37 micromol x h(-1) x kg(-1) (P = 0.026). By difference, this implies a rate of CO(2) formation from the glycine 2-carbon of 51 +/- 40 micromol x h(-1) x kg(-1), which accounts for approximately 35% of the total CO(2) generated in glycine catabolism. These findings also indicate that approximately 65% of the CO(2) generation from glycine occurs by decarboxylation, primarily from the GCS. Further, these results suggest that the GCS is responsible for the entry of 5,10-methylenetetrahydrofolate into 1-carbon metabolism at a very high rate ( approximately 96 micromol x h(-1) x kg(-1)), which is approximately 20 times the demand for methyl groups for homocysteine remethylation.

Vascular dysfunction in glycogen storage disease type I.

OBJECTIVE: To determine cardiovascular disease risk in a larger cohort of patients with glycogen storage disease (GSD) I through the use of noninvasive measures of arterial function and anatomy. STUDY DESIGN: Carotid intima media thickness (IMT), radial artery tonometry, and brachial artery reactivity were performed in 28 patients with GSD I (13F/15M, mean age 23 years) and 23 control subjects (19F/4M, mean age 23 years). RESULTS: The primary outcome measure, mean left distal IMT was greater in the GSD cohort (0.500+/-0.055 mm) than in the control group (0.457+/-0.039 mm) (P= .002, adjusted for age, sex, and body mass index). Mean augmentation index measured by radial artery tonometry was higher in the GSD cohort (16.4%+/-14.0%) than in the control group (2.4%+/-8.7%) (P< .001). No significant difference was observed between mean brachial artery reactivity in the GSD cohort (6.3%+/-4.9% change) versus control subjects (6.6%+/-5.1% change) (P= .46). CONCLUSIONS: GSD I is associated with arterial dysfunction evident by increased IMT and augmentation index. Patients with GSD I may be at increased risk for cardiovascular disease.

The effects of local anesthetic concentration and dose on continuous infraclavicular nerve blocks: a multicenter, randomized, observer-masked, controlled study.

BACKGROUND: It remains unclear whether local anesthetic concentration or total drug dose is the primary determinant of continuous peripheral nerve block effects. The only previous investigation, involving continuous popliteal-sciatic nerve blocks, specifically addressing this issue reported that insensate limbs were far more common with higher volumes of relatively dilute ropivacaine compared with lower volumes of relatively concentrated ropivacaine. However, it remains unknown if this relationship is specific to the sciatic nerve in the popliteal fossa or whether it varies depending on anatomic location. We therefore tested the null hypothesis that providing ropivacaine at different concentrations and rates, but at an equal total basal dose, produces comparable effects when used in a continuous infraclavicular brachial plexus block. METHODS: Preoperatively, an infraclavicular catheter was inserted using the coracoid approach in patients undergoing moderately painful orthopedic surgery distal to the elbow. Patients were randomly assigned to receive a postoperative perineural ropivacaine infusion of either 0.2% (basal 8 mL/h, bolus 4 mL) or 0.4% (basal 4 mL/h, bolus 2 mL) through the second postoperative day. Both groups, therefore, received 16 mg of ropivacaine each hour with a possible addition of 8 mg every 30 min via a patient-controlled bolus dose. Our primary end point was the incidence of an insensate limb during the 24-h period beginning the morning after surgery. Secondary end points included analgesia and patient satisfaction. RESULTS: Patients given 0.4% ropivacaine (n = 27) experienced an insensate limb, a mean (sd) of 1.8 (1.6) times, compared with 0.6 (0.9) times for subjects receiving 0.2% ropivacaine (n = 23; estimated difference = 1.2 episodes, 95% confidence interval, 0.5-1.9 episodes; P = 0.001). Satisfaction with postoperative analgesia (scale 0-10, 10 = highest) was scored a median (25th-75th percentiles) of 10.0 (8.0-10.0) in Group 0.2% and 7.0 (5.3-8.9) in Group 0.4% (P = 0.018). Analgesia was similar in each group. CONCLUSIONS: For continuous infraclavicular nerve blocks, local anesthetic concentration and volume influence perineural infusion effects in addition to the total mass of local anesthetic administered. Insensate limbs were far more common with smaller volumes of relatively concentrated ropivacaine. This is the opposite of the relationship previously reported for continuous popliteal-sciatic nerve blocks. The interaction between local anesthetic concentration and volume is thus complex and varies among catheter locations.

Neonatal heart rate variability and intraventricular hemorrhage: a case study.

PURPOSE: The purpose of this study was to compare heart rate variability (HRV) in low-risk, pre-term infants to one infant diagnosed with intraventricular hemorrhage (IVH). METHOD: A case study design was used to compare HRV of one subject diagnosed with IVH to a convenience sample of 38 low-risk, pre-term infants at 30 and 31 post-menstrual weeks of age. Heart periods were recorded for 300-s with the infant in an active sleep state. Heart rate variability was quantified by spectral analysis. A confidence interval comparison of the total spectral components (0.02-2.0 Hz), high-frequency components (0.20-2.0 Hz), and the low-frequency components (0.02-0.20 Hz) was conducted. FINDINGS: At 30 weeks' post-menstrual age, 10 days following diagnosis, with a grade-III IVH, the low frequency components were above the 90th percentile. One week later, at 31 weeks, the low frequency components had decreased to the 27th percentile range, and the total and high frequency components were at or below the 25th percentile range of the confidence intervals for the low-risk, pre-term infants. DISCUSSION: The neurobehavioral organization of pre-term infants is limited due to prematurity and the cumulative effect of medical complications (such as IVH). This study has implications for the use of HRV in the identification of infants diagnosed with IVH.

Applying Hodges-Lehmann scale parameter estimates to hospital discharge times.

BACKGROUND: Clinical trials aimed at shortening the time-to-discharge need to have rational and easily understood effect size estimates for health care management organizations. A natural choice is a scale model, where the distribution of time to discharge on one treatment is assumed to be the same as rho times that on the other. If, for example rho=0.6, then one treatment is associated with a 40% reduction in discharge time. In designing and analyzing these studies, we need to have the capability to accommodate right censored data, as it is plausible that some patients may never meet the discharge criteria, even though they do get discharged. PURPOSE: Utilizing the ideas of Hodges and Lehmann, to provide methods for analysis of trials aimed at shortening hospital discharge times, using point and interval estimates of scale parameters based on the Gehan generalization of the Mann-Whitney-Wilcoxon test, which accommodates right censoring for situations where patients never meet discharge criteria (+infinity). METHODS: For every value of rho > 0, we shall test the null hypothesis that the distribution of discharge times on one treatment is the same rho times that on the other. The values of rho that we fail to reject form the confidence interval for the true rho. RESULTS: The methods were developed and applied to a real clinical trial for times to meet the three objective discharge criteria in knee replacement surgery for two post-operative pain control strategies (usual care plus a perineural infusion of either placebo or 0.2% ropivocaine, until the morning following surgery). Based on 48 randomized patients, the point estimate (95% confidence limits) for rho was 0.47 (0.32-0.67), favoring ropivocaine. LIMITATIONS: The methods cannot as yet be applied to group sequential designs or studies with more than two treatments. CONCLUSION: This methodology is an effective way to analyze two-arm trials involving continuous hospital discharge time data.

Use of modified cornstarch therapy to extend fasting in glycogen storage disease types Ia and Ib.

BACKGROUND: Type I glycogen storage disease (GSD) is caused by a deficiency of glucose-6-phosphatase resulting in severe fasting hypoglycemia. OBJECTIVE: We compared the efficacy of a new modified starch with the currently used cornstarch therapy in patients with type Ia and Ib GSD. DESIGN: This was a randomized, 2-d, double-blinded, crossover pilot study comparing the commonly used uncooked cornstarch with the experimental starch in 12 subjects (6 GSDIa, 6 GSDIb) aged >or=13 y. At 2200, the subjects were given 100 g of digestible starch, and glucose and lactate were measured hourly until the subject's plasma glucose concentration reached 60 mg/dL or until the subject had fasted for 10 h. The order in which the products were tested was randomized in a blinded fashion. RESULTS: The matched-pair Gehan rank test for censored survival was used to compare the therapies. The experimental starch maintained blood glucose concentrations significantly longer than did the traditional therapy (P = 0.013) in the 2-sided analysis. Most of the benefit was found to be after glucose concentrations fell below 70 mg/dL. The currently used cornstarch resulted in higher peak glucose concentrations and a more rapid rate of fall than did the new starch. CONCLUSIONS: The experimental starch was superior to standard therapy in preventing hypoglycemia (

Ambulatory continuous posterior lumbar plexus nerve blocks after hip arthroplasty: a dual-center, randomized, triple-masked, placebo-controlled trial.

BACKGROUND: The authors tested the hypotheses that after hip arthroplasty, ambulation distance is increased and the time required to reach three specific readiness-for-discharge criteria is shorter with a 4-day ambulatory continuous lumbar plexus block (cLPB) than with an overnight cLPB. METHODS: A cLPB consisting of 0.2% ropivacaine was provided from surgery until the following morning. Patients were then randomly assigned either to continue ropivacaine or to be switched to normal saline. Primary endpoints included (1) time to attain three discharge criteria (adequate analgesia, independence from intravenous analgesics, and ambulation > or = 30 m) and (2) ambulatory distance in 6 min the afternoon after surgery. Patients were discharged with their cLPB and a portable infusion pump, and catheters were removed on the fourth postoperative day. RESULTS: Patients given 4 days of perineural ropivacaine (n = 24) attained all three discharge criteria in a median (25th-75th percentiles) of 29 (24-45) h, compared with 51 (42-73) h for those of the control group (n = 23; estimated ratio = 0.62; 95% confidence interval, 0.45-0.92; P = 0.011). Patients assigned to receive ropivacaine ambulated a median of 34 (9-55) m the afternoon after surgery, compared with 20 (6-46) m for those receiving normal saline (estimated ratio = 1.3; 95% confidence interval, 0.6-3.0; P = 0.42). Three falls occurred in subjects receiving ropivacaine (13%), versus none in subjects receiving normal saline. CONCLUSIONS: Compared with an overnight cLPB, a 4-day ambulatory cLPB decreases the time to reach three predefined discharge criteria by an estimated 38% after hip arthroplasty. However, the extended infusion did not increase ambulation distance to a statistically significant degree.