Biomedical subjects

Lisa O'Brien

Publications and source records attributed to Lisa O'Brien.

5 recordsLinked to original sources

PubMed2005

A critical review of the topical local anesthetic amethocaine (Ametop) for pediatric pain.

A topical formulation of the ester-type local anesthetic amethocaine (tetracaine) [Ametop ] is currently available for reducing pain from cutaneous procedures such as venipuncture. The Ametop mark preparation contains 40 mg of amethocaine base (4% w/w) and produces anesthesia within 30-45 minutes of application; duration of action ranges from 4 to 6 hours. Clinical studies have demonstrated the superiority of the 4% amethocaine preparation over placebo in pediatric populations for indications such as intravenous cannulation, vaccination, and venipuncture. Amethocaine has been shown to produce anesthesia comparable to that of 5% lidocaine-prilocaine for procedures such as venipuncture and accessing centrally placed devices; in general, anesthesia was achieved more rapidly with amethocaine than lidocaine-prilocaine. In the neonatal population amethocaine was found to be ineffective at reducing the pain of heel prick and peripherally inserted central catheters. Depending on the type of procedure, amethocaine application times between 30 and 60 minutes have produced clinically acceptable anesthesia; application times <30 minutes have not been associated with reliable anesthesia. The 4% amethocaine preparation is well tolerated; the most commonly reported local skin reaction is transient local erythema while local edema and itching have been reported more rarely. There have been no accounts of systemic toxicity with topical use of the preparation. Several cases of sensitization have been described in adults upon repeated exposure to topical amethocaine. In summary, the novel preparation of 4% amethocaine gel has been shown to be clinically effective for managing pain associated with minor cutaneous procedures while maintaining a good tolerability profile. Amethocaine has also demonstrated similar efficacy to lidocaine-prilocaine when appropriate application times are used; the more rapid onset of action and extended duration of action of amethocaine may make it more useful than lidocaine-prilocaine in busy clinical settings.

Adolescent↗

PubMed2004

Effect of age on the pharmacokinetics of duloxetine in women.

AIMS: The effect of age on duloxetine pharmacokinetics was evaluated in healthy volunteers and in patients with urinary incontinence. METHODS: Twenty-four healthy subjects (12 women 65-77 years, and 12 women 32-50 years) were given a single 40-mg oral dose of duloxetine in Study 1. Plasma concentration-time data were analysed by noncompartmental pharmacokinetic methods. Sparse plasma samples were obtained from patients with urinary incontinence treated in two phase II studies: 70 women (24-77 years) who received duloxetine 20 mg day(-1), 30 mg day(-1), or 40 mg day(-1) in Study 2A and 128 women (28-64 years) who received duloxetine 20 mg day(-1), 40 mg day(-1), or 80 mg day(-1) in Study 2B. Based upon the combined data, a model was developed to characterize population pharmacokinetics of duloxetine using the nonlinear mixed-effects modelling program (NONMEM). RESULTS: In Study 1, the elderly (> or = 65 years) exhibited a statistically significant slower elimination rate constant lambdaz compared with younger subjects [elderly-younger difference = -0.022 h(-1)[95% confidence interval (CI) -0.036, -0.008]]. However, no statistically significant differences in either CL/F [elderly-younger difference = -17.4 l h(-1) (95% CI -41.1, 6.23)] or V/F [elderly-younger difference = 115.9 l (95% CI -168.6, 400.4)] were observed. The population pharmacokinetic analysis of Studies 2A and 2B revealed that the CL/F of duloxetine decreased with increasing age. Despite statistical significance, the age effect only accounted for 3% of the interindividual variability in CL/F and unexplained sources of the variation in clearance were still substantial (> 50%). Adverse events were generally mild to moderate, and the incidence of adverse events was generally similar in elderly and non-elderly participants in these studies. CONCLUSIONS: Whereas the results suggest that age has an effect on duloxetine pharmacokinetics, primarily reflected as a slower lambdaz in the elderly, the magnitude of mean changes in CL/F, or V/F was small relative to the large interindividual variation in pharmacokinetics. Elderly participants had a safety profile of duloxetine comparable to their younger counterparts. Specific dose recommendations for duloxetine in the elderly are not warranted.

Adrenergic Uptake Inhibitors↗

PubMed2004

Topical 4% amethocaine gel reduces the pain of subcutaneous measles-mumps-rubella vaccination.

OBJECTIVES: Ametop gel (4% amethocaine) is a relatively new topical anesthetic that produces anesthesia within 30 to 45 minutes and therefore may be appropriate for use in busy outpatient settings. The objective of this study was to assess the efficacy and safety of 4% amethocaine in reducing the pain of subcutaneous measles-mumps-rubella vaccination in 1-year-old infants. METHODS: A double-blind, randomized, placebo-controlled trial was conducted in pediatric outpatient clinics. RESULTS: A total of 120 infants participated in the study; 60 were followed up for assessment of antibody titers after 1 month. Either 1 g of amethocaine or placebo was applied for 30 minutes before vaccination. The Modified Behavioral Pain Scale was used to assess pain; the mean (standard deviation) pain scores for the amethocaine group (n = 61) was 1.5 (1.6) versus 2.3 (2.2) for the placebo group (n = 59). The rate of vaccination success (88% and 87%) was not different between treatment groups. CONCLUSIONS: 4% Amethocaine significantly reduces the pain of measles-mumps-rubella vaccination in infants when compared with placebo and does not seem to interfere with subsequent development of protective antibody levels. Because of its relatively short application time (30 minutes), 4% amethocaine may be suitable for busy clinics and emergency departments.

Anesthetics, Local↗

PubMed2003

Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome.

Dementia of the Alzheimer type (DAT) is common in older persons with Down syndrome (DS). There are three common alleles of the apolipoprotein E (ApoE) gene (Sigma 2, Sigma 3, and Sigma 4) resulting in three different isoforms (E2, E3, and E4) and six different genotypes (2,2; 2,3; 2,4; 3,3; 3,4; and 4,4). Sigma 4 is a risk factor for DAT whereas Sigma 2 appears prophylactic. As hepatitis B virus (HBV) infection and hypothyroidism also are common in DS, we evaluated associations between ApoE type, HBV status, and thyroid status in a sample of older persons with DS (n = 55; mean age, 44.3 +/- 10.8 years) using chi-squared analysis. Participants were classified as E2 (2,2 or 2,3), E3 (3,3), or E4 (3,4 or 4,4); positive for markers of HBV infection in the present or past (i.e., total HBcAb+ and/or HBsAg+ with or without infectivity, defined as HBV+) or negative for markers of HBV infection (defined as HBV-) and, currently receiving thyroid hormone supplement (defined as "hypothyroidism") or having normal thyroid function. The majority of the HBV+ were currently HBcAb+ and HBsAb+, but not HBsAg+. In females, there was an ApoE allele effect on thyroid status (P < or = 0.01), E2 being negatively (P < or = 0.01) and E4 being positively (P < or = 0.05) associated with "hypothyroidism". There was no evidence for an ApoE allele effect on thyroid status in males. There was no evidence for an ApoE allele effect on HBV status, or for an HBV status effect on thyroid status. As thyroid status can affect cognitive function, ApoE allele effects in DAT may, in part, be thyroid effects.

Adult↗

PubMed2003

Evaluation of a new lancet device (BD QuikHeel) on pain response and success of procedure in term neonates.

OBJECTIVE: To evaluate 2 heel lancet devices in terms of pain response and success of the procedure in neonates undergoing the newborn screening test. DESIGN: Randomized trial. SETTING: Tenth level, mother-and-baby unit of a university-affiliated hospital. Patients Eighty term neonates. INTERVENTIONS: Heel lance using either the BD Safety-Flow lancet (SF) or the BD QuikHeel lancet (QH). MAIN OUTCOME MEASURES: Facial grimacing score (brow bulge, eye squeezed shut, and nasolabial furrow [range, 0%-100%]), cry duration, duration of the procedure, and number of punctures required to collect the blood. RESULTS: Forty neonates were enrolled in each group. There were no differences in the demographic characteristics between groups. During the first skin puncture, the median score (25th-75th percentile) for facial grimacing was 100% (76%-100%) for the SF compared with 73% (42%-100%) for the QH (P =.02). For cry duration, it was 6 seconds (0-9 seconds) vs 0 seconds (0-6 seconds), respectively (P =.01). Pain scores during blood collection (ie, squeezing) did not differ between groups (P =.09). The procedure took less time to perform in the QH group (140 seconds [90-236 seconds]) than in the SF group (215 seconds [137-314 seconds]) (P =.02). The total crying time was shorter in the QH group (90 seconds [66-196 seconds] vs 148 seconds [92-267 seconds]; P =.03). Thirty-six (90%) of the neonates in the QH group received 1 puncture for blood collection compared with 21 (53%) in the SF group (P<.001). CONCLUSION: The BD QuikHeel lancet is superior to the BD Safety-Flow lancet for blood collection in term neonates undergoing the newborn screening test.

Blood Specimen Collection↗