Essential medicines containing ethanol elevate blood acetaldehyde concentrations in neonates.

UNLABELLED: Neonates administered ethanol-containing medicines are potentially at risk of dose-dependent injury through exposure to ethanol and its metabolite, acetaldehyde. Here, we determine blood ethanol and acetaldehyde concentrations in 49 preterm infants (median birth weight = 1190 g) dosed with iron or furosemide, medicines that contain different amounts of ethanol, and in 11 control group infants (median birth weight = 1920 g) who were not on any medications. Median ethanol concentrations in neonates administered iron or furosemide were 0.33 (range = 0-4.92) mg/L, 0.39 (range = 0-72.77) mg/L and in control group infants were 0.15 (range = 0.03-5.4) mg/L. Median acetaldehyde concentrations in neonates administered iron or furosemide were 0.16 (range = 0-8.89) mg/L, 0.21 (range = 0-2.43) mg/L and in control group infants were 0.01 (range = 0-0.14) mg/L. There was no discernible relationship between blood ethanol or acetaldehyde concentrations and time after medication dose. CONCLUSION: Although infants dosed with iron or furosemide had low blood ethanol concentrations, blood acetaldehyde concentrations were consistent with moderate alcohol exposure. The data suggest the need to account for the effects of acetaldehyde in the benefit-risk analysis of administering ethanol-containing medicines to neonates. WHAT IS KNOWN: • Neonates are commonly treated with ethanol-containing medicines, such as iron and furosemide. • However, there is no data on whether this leads to appreciable increases in blood concentrations of ethanol or its metabolite, acetaldehyde. What is New: • In this study, we find low blood ethanol concentrations in neonates administered iron and/or furosemide but markedly elevated blood acetaldehyde concentrations in some infants receiving these medicines. • Our data suggest that ethanol in drugs may cause elevation of blood acetaldehyde, a potentially toxic metabolite.

Tackling the problem of blood culture contamination in the intensive care unit using an educational intervention.

Blood culture contamination (BCC) has been associated with unnecessary antibiotic use, additional laboratory tests and increased length of hospital stay thus incurring significant extra hospital costs. We set out to assess the impact of a staff educational intervention programme on decreasing intensive care unit (ICU) BCC rates to <3% (American Society for Microbiology standard). BCC rates during the pre-intervention period (January 2006-May 2011) were compared with the intervention period (June 2011-December 2012) using run chart and regression analysis. Monthly ICU BCC rates during the intervention period were reduced to a mean of 3.7%, compared to 9.5% during the baseline period (P < 0.001) with an estimated potential annual cost savings of about £250,100. The approach used was simple in design, flexible in delivery and efficient in outcomes, and may encourage its translation into clinical practice in different healthcare settings.

An observational study of blood concentrations and kinetics of methyl- and propyl-parabens in neonates.

PURPOSE: Systemic exposure to parabens in the neonatal population, in particular propyl-parabens (PPB), remains a concern. Blood concentrations and kinetics of methyl-parabens (MPB) and PPB were therefore determined in neonates receiving medicines containing these excipients. METHODS: A multi-centre, non-interventional, observational study of excipient-kinetics in neonates. 'Dried Blood Spot' samples were collected opportunistically at the same time as routine samples and the observations modelled using a non-linear mixed effects approach. RESULTS: A total of 841 blood MPB and PPB concentration data were available for evaluation from 181 pre- and term-neonates. Quantifiable blood concentrations of MPB and PPB were observed in 99% and 49% of patients, and 55% and 25% of all concentrations were above limit of detection (10 ng/ml), respectively. Only MPB data was amenable to modelling. Oral bioavailability was influenced by type of formulation and disposition was best described by a two compartment model with clearance (CL) influenced by post natal age (PNA); CL PNA<21 days 0.57 versus CL PNA>21 days 0.88 L/h. CONCLUSIONS: Daily repeated administration of parabens containing medicines can result in prolonged systemic exposure to the parent compound in neonates. Animal toxicology studies of PPB that specifically address the neonatal period are required before a permitted daily exposure for this age group can be established.

Hospital antibiotic use and its relationship to age-adjusted comorbidity and alcohol-based hand rub consumption.

The objective of this study was to evaluate the effect of age-adjusted comorbidity and alcohol-based hand rub on monthly hospital antibiotic usage, retrospectively. A multivariate autoregressive integrated moving average (ARIMA) model was built to relate the monthly use of all antibiotics grouped together with age-adjusted comorbidity and alcohol-based hand rub over a 5-year period (April 2005-March 2010). The results showed that monthly antibiotic use was positively related to the age-adjusted comorbidity index (concomitant effect, coefficient 1·103, P = 0·0002), and negatively related to the use of alcohol-based hand rub (2-month delay, coefficient -0·069, P = 0·0533). Alcohol-based hand rub is considered a modifiable factor and as such can be identified as a target for quality improvement programmes. Time-series analysis may provide a suitable methodology for identifying possible predictive variables that explain antibiotic use in healthcare settings. Future research should examine the relationship between infection control practices and antibiotic use, identify other infection control predictive factors for hospital antibiotic use, and evaluate the impact of enhancing different infection control practices on antibiotic use in a healthcare setting.

Impact of an enhanced antibiotic stewardship on reducing methicillin-resistant Staphylococcus aureus in primary and secondary healthcare settings.

The objective of this study was to evaluate the impact of restricting high-risk antibiotics on methicillin-resistant Staphylococcus aureus (MRSA) incidence rates in a hospital setting. A secondary objective was to assess the impact of reducing fluoroquinolone use in the primary-care setting on MRSA incidence in the community. This was an interventional, retrospective, ecological investigation in both hospital and community (January 2006 to June 2010). Segmented regression analysis of interrupted time-series was employed to evaluate the intervention. The restriction of high-risk antibiotics was associated with a significant change in hospital MRSA incidence trend (coefficient=-0·00561, P=0·0057). Analysis showed that the intervention relating to reducing fluoroquinolone use in the community was associated with a significant trend change in MRSA incidence in community (coefficient=-0·00004, P=0·0299). The reduction in high-risk antibiotic use and fluoroquinolone use contributed to both a reduction in incidence rates of MRSA in hospital and community (primary-care) settings.

Risk assessment of neonatal excipient exposure: lessons from food safety and other areas.

Newborn babies can require significant amounts of medication containing excipients intended to improve the drug formulation. Most medicines given to neonates have been developed for adults or older children and contain excipients thought to be safe in these age groups. Many excipients have been used widely in neonates without obvious adverse effects. Some excipients may be toxic in high amounts in which case they need careful risk assessment. Alternatively, it is conceivable that ill-founded fears about excipients mean that potentially useful medicines are not made available to newborn babies. Choices about excipient exposure can occur at several stages throughout the lifecycle of a medicine, from product development through to clinical use. Making these choices requires a scalable approach to analysing the overall risk. In this contribution we examine these issues.

A simple bioanalytical method for the quantification of antiepileptic drugs in dried blood spots.

An increasing number of publications on the dried blood spot (DBS) sampling approach for the quantification of drugs and metabolites have been spurred on by the inherent advantages of this sampling technique. In the present research, a selective and sensitive high-performance liquid chromatography method for the concurrent determination of multiple antiepileptic drugs (AEDs) [levetiracetam (LVT), lamotrigine (LTG), phenobarbital (PHB)], carbamazepine (CBZ) and its active metabolite carbamazepine-10,11 epoxide (CBZE)] in a single DBS has been developed and validated. Whole blood was spotted onto Guthrie cards and dried. Using a standard punch (6mm diameter), a circular disc was punched from the card and extracted with methanol: acetonitrile (3:1, v/v) containing hexobarbital (Internal Standard) and sonicated prior to evaporation. The extract was then dissolved in water and vortex mixed before undergoing solid phase extraction using HLB cartridges. Chromatographic separation of the AEDs was achieved using Waters XBridge™ C18 column with a gradient system. The developed method was linear over the concentration ranges studied with r≥0.995 for all compounds. The lower limits of quantification (LLOQs) were 2, 1, 2, 0.5 and 1 µg/mL for LVT, LTG, PHB, CBZE and CBZ, respectively. Accuracy (%RE) and precision (%CV) values for within and between day were <20% at the LLOQs and <15% at all other concentrations tested. This method was successfully applied to the analysis of the AEDs in DBS samples taken from children with epilepsy for the assessment of their adherence to prescribed treatments.

Population pharmacokinetics of single-dose intravenous paracetamol in children.

BACKGROUND: To determine the pharmacokinetics (PK) of a new i.v. formulation of paracetamol (Perfalgan) in children ≤15 yr of age. METHODS: After obtaining written informed consent, children under 16 yr of age were recruited to this study. Blood samples were obtained at 0, 15, 30 min, 1, 2, 4, 6, and 8 h after administration of a weight-dependent dose of i.v. paracetamol. Paracetamol concentration was measured using a validated high-performance liquid chromatographic assay with ultraviolet detection method, with a lower limit of quantification (LLOQ) of 900 pg on column and an intra-day coefficient of variation of 14.3% at the LLOQ. Population PK analysis was performed by non-linear mixed-effect modelling using NONMEM. RESULTS: One hundred and fifty-nine blood samples from 33 children aged 1.8-15 yr, weight 13.7-56 kg, were analysed. Data were best described by a two-compartment model. Only body weight as a covariate significantly improved the goodness of fit of the model. The final population models for paracetamol clearance (CL), V(1) (central volume of distribution), Q (inter-compartmental clearance), and V(2) (peripheral volume of distribution) were: 16.51×(WT/70)(0.75), 28.4×(WT/70), 11.32×(WT/70)(0.75), and 13.26×(WT/70), respectively (CL, Q in litres per hour, WT in kilograms, and V(1) and V(2) in litres). CONCLUSIONS: In children aged 1.8-15 yr, the PK parameters for i.v. paracetamol were not influenced directly by age but were by total body weight and, using allometric size scaling, significantly affected the clearances (CL, Q) and volumes of distribution (V(1), V(2)).

A point prevalence survey of antibiotic use in four acute-care teaching hospitals utilizing the European Surveillance of Antimicrobial Consumption (ESAC) audit tool.

The objective of this research was to assess current patterns of hospital antibiotic prescribing in Northern Ireland and to determine targets for improving the quality of antibiotic prescribing. A point prevalence survey was conducted in four acute teaching hospitals. The most commonly used antibiotics were combinations of penicillins including ß-lactamase inhibitors (33·6%), metronidazole (9·1%), and macrolides (8·1%). The indication for treatment was recorded in 84·3% of the prescribing episodes. A small fraction (3·9%) of the surgical prophylactic antibiotic prescriptions was for >24 h. The results showed that overall 52·4% of the prescribed antibiotics were in compliance with the hospital antibiotic guidelines. The findings identified the following indicators as targets for quality improvement: indication recorded in patient notes, the duration of surgical prophylaxis and compliance with hospital antibiotic guidelines. The results strongly suggest that antibiotic use could be improved by taking steps to address the identified targets for quality improvement.

Clinical and economic impact of contaminated blood cultures within the hospital setting.

Blood cultures have an important role in the diagnosis of serious infections, although contamination of blood cultures (i.e. false-positive blood cultures) is a common problem within the hospital setting. The objective of the present investigation was to determine the impact of the false-positive blood culture results on the following outcomes: length of stay, hotel costs, antimicrobial costs, and costs of laboratory and radiological investigation. A retrospective case-control study design was used in which 142 false-positive blood culture cases were matched with suitable controls (patients for whom cultures were reported as true negatives). The matching criteria included age, comorbidity score and month of admission to the hospital. The research covered a 13-month period (July 2007 to July 2008). The findings indicated that differences in means, between cases and controls, for the length of hospital stay and the total costs were 5.4 days [95% CI (confidence interval): 2.8-8.1 days; P<0.001] and £5,001.5 [$7,502.2; 95% CI: £3,283.9 ($4,925.8) to £6,719.1 ($10,078.6); P<0.001], respectively. Consequently, and considering that 254 false-positive blood cultures had occurred in the study site hospital over a one-year period, patients with false-positive blood cultures added 1372 extra hospital days and incurred detrimental additional hospital costs of £1,270,381 ($1,905,572) per year. The findings therefore demonstrate that false-positive blood cultures have a significant impact on increasing hospital length of stay, laboratory and pharmacy costs. These findings highlight the need to intervene to raise the standard of blood-culture-taking technique, thus improving both the quality of patient care and resource use.

Can the use of a rapid polymerase chain screening method decrease the incidence of nosocomial meticillin-resistant Staphylococcus aureus?

Rapid detection of MRSA may be important for the control of MRSA spread in hospitals. The aim of this investigation was to compare the use of a rapid polymerase chain reaction (PCR) screening method with standard culture for the detection of meticillin-resistant Staphylococcus aureus (MRSA) colonisation and to determine its impact on the incidence of MRSA in two hospital wards. During the first phase of the investigation (four months), patients in a surgical ward were screened using the rapid PCR technique and patients in a medical/cardiology ward were screened with standard culture methods. During the second phase of the investigation (four months), MRSA screening methods were switched between the two wards. An audit of infection control practices on each ward was made at the end of each phase in order to check whether any changes had occurred that might influence the risks of MRSA transmission. Use of the rapid PCR method significantly reduced the median time between swabs being taken, to the results being telephoned to the wards (excluding weekends), from 47 to 21 h (P<0.001). However, comparison of MRSA incidence during use of PCR (20/1000 bed-days) and culture methods (22.1/1000 bed-days) revealed no significant difference in incidence on the surgical ward (P=0.69). Regarding the medical/cardiology ward, analysis of data was complicated by an increase in the detection of MRSA during the PCR phase (P<0.05). The study demonstrated that rapid PCR can significantly reduce the turnaround times but reducing the time between swabs being taken to results being telephoned to the ward is still not sufficient to limit the transmission of MRSA.

Public awareness and views on unlicensed use of medicines in children.

AIMS: To explore awareness and views of the general public on unlicensed use of medicines in children and on the participation of children in clinical trials. METHODS: Members of the public completed a questionnaire survey administered by face-to-face interview in public areas in N. Ireland. The main outcome measures were the views on unlicensed use of medicines in children and on clinical trials in children. RESULTS: One thousand participants (59.2% female) took part; 610 were parents. Most participants (86%) had no previous knowledge about unlicensed use of medicines in children. Being a parent did not influence this nor did being a parent of a child who suffered from a health problem (P > 0.05). Most participants (92%) felt that parents should be told about unlicensed use of medicines, with the doctor most frequently selected as the person who should inform parents. At the outset, only 1.8% of participants felt that the use of medicines in children was unsafe. However, having been informed about unlicensed use of medicines, this proportion increased dramatically (62.4%; P < 0.001). Views on whether participants would enter a child of their own into a clinical trial varied according to the health status of the child (P < 0.05) i.e. a child in good health (3.9%) vs a child with a life-threatening condition (41.9%). CONCLUSIONS: There is limited public knowledge of unlicensed use of medicines in children and a general reluctance to involve children in clinical trials unless the child to be involved has a life-threatening condition.

Sputum antibiotic concentrations: implications for treatment of cystic fibrosis lung infection.

BACKGROUND: The success of antibiotic therapy may be predicted based on the achievement of pharmacodynamic indices (PDIs), which are determined by the susceptibility of the infecting bacteria and the concentrations of antibiotics achieved at the site of infection. The aim of this study was to determine whether PDIs associated with clinical effectiveness for ceftazidime and tobramycin were achieved at the site of infection in the lungs of cystic fibrosis (CF) patients following intravenous administration during treatment of an acute exacerbation. METHODS: Serum and sputum samples were collected from 14 CF patients and the concentration of both antibiotics in the samples determined. The susceptibility of bacteria cultured from sputum samples to both antibiotics alone and in combination was also determined. RESULTS: A total of 22 Pseudomonas aeruginosa isolates and 4 Burkholderia cepacia complex isolates were cultured from sputum samples with 55% and 4% of isolates susceptible to ceftazidime and tobramycin, respectively. Target PDIs for ceftazidime and tobramycin, an AUC/MIC ratio of 100 and a C(max)/MIC ratio of 10, respectively, were not achieved in serum or sputum simultaneously or even individually for any patient. Although the combination of ceftazidime and tobramycin was synergistic against 20 of the 26 isolates cultured, the concentrations of both antibiotics required for synergy were achieved simultaneously in only 38% of serum and 14% of sputum samples. CONCLUSION: Key PDIs associated with clinical effectiveness for ceftazidime and tobramycin were not achieved at the site of infection in the lungs of CF patients.

A cross-sectional study evaluating the relationship between cortisol suppression and asthma control in patients with difficult asthma.

AIM: To examine the relationship between cortisol suppression and asthma symptoms in patients with difficult asthma. METHODS: Patients, referred to a specialist difficult asthma service and who fulfilled the criteria for difficult asthma, were recruited to the study in a sequential, unselected manner. At each clinic visit, all patients completed a validated asthma control questionnaire. For measuring cortisol suppression, early morning urinary cortisol [corrected for creatinine to give urinary cortisol creatinine ratio (UCC ratio)] was used. The urine samples were collected and stored at -70 degrees C until ready for analysis. Urinary cortisol was extracted (solid-phase extraction) and analysed using high-performance liquid chromatography. The Pearson correlation coefficient was used for correlation analysis while t-tests were used for between-group differences for normally distributed data. If the data were not normally distributed, nonparametric statistics were used. A P-value < 0.05 was considered statistically significant. RESULTS: During the study period all the patients who attended the difficult asthma clinic and fulfilled the criteria for difficult asthma (n = 66) agreed to take part in the study. There were moderate to strong and significant associations between several measures of asthma control and UCC ratio. The correlation coefficient with five indicators of asthma control ranged between 0.3 and 0.5 (P < 0.05). CONCLUSIONS: We have demonstrated a relationship between cortisol suppression and asthma control in difficult asthmatics on high-dose steroid therapy. We have proposed a model based on the relationship between symptom control and cortisol suppression, whereby both adherence and therapeutic adjustments could potentially be made. A properly controlled prospective clinical trial should examine the utility of this approach in clinical practice.

Development and validation of an HPLC method for the determination of spironolactone and its metabolites in paediatric plasma samples.

An HPLC method has been developed and validated for the determination of spironolactone, 7 alpha-thiomethylspirolactone and canrenone in paediatric plasma samples. The method utilises 200 microl of plasma and sample preparation involves protein precipitation followed by Solid Phase Extraction (SPE). Determination of standard curves of peak height ratio (PHR) against concentration was performed by weighted least squares linear regression using a weighting factor of 1/concentration2. The developed method was found to be linear over concentration ranges of 30-1000 ng/ml for spironolactone and 25-1000 ng/ml for 7 alpha-thiomethylspirolactone and canrenone. The lower limit of quantification for spironolactone, 7 alpha-thiomethylspirolactone and canrenone were calculated as 28, 20 and 25 ng/ml, respectively. The method was shown to be applicable to the determination of spironolactone, 7 alpha-thiomethylspirolactone and canrenone in paediatric plasma samples and also plasma from healthy human volunteers.

Dried blood spot liquid chromatography assay for therapeutic drug monitoring of metformin.

The use of blood spot collection cards is a simple way to obtain specimens for analysis of drugs for the purpose of therapeutic drug monitoring, assessing adherence to medications and preventing toxicity in routine clinical setting. We describe the development and validation of a microanalytical technique for the determination of metformin from dried blood spots. The method is based on reversed phase high-performance liquid chromatography with ultraviolet detection. Drug recovery in the developed method was found to be more than 84%. The limits of detection and quantification were calculated to be to be 90 and 150 ng/ml, respectively. The intraday and interday precision (measured by CV%) was always less than 9%. The accuracy (measured by relative error, %) was always less than 12%. Stability analysis showed that metformin is stable for at least 2 months when stored at -70 degrees C. The small volume of blood required (10 microL), combined with the simplicity of the analytical technique makes this a useful procedure for monitoring metformin concentrations in routine clinical settings. The method is currently being applied to the analysis of blood spots taken from diabetic patients to assess adherence to medications and relationship between metformin level and metabolic control of diabetes.

Pharmaceutical care of patients with heart failure.

AIM: The aim of this study was to investigate the impact of a pharmacist-led pharmaceutical care programme, involving optimization of drug treatment and intensive education and self-monitoring of patients with heart failure (HF) within the United Arab Emirates (UAE), on a range of clinical and humanistic outcome measures. METHODS: The study was a randomized, controlled, longitudinal, prospective clinical trial at Al-Ain Hospital, Al-Ain, UAE. Patients were recruited from the general medical wards and from cardiology and medical outpatient clinics. HF patients who fulfilled the entrance criteria, and had no exclusion criteria present, were identified for inclusion in the study. After recruitment, patients were randomly assigned to one of two groups: intervention group or control group. Intervention patients received a structured pharmaceutical care service while control patients received traditional services. Patient follow-up took place when patients attended scheduled outpatient clinics (every 3 months). A total of 104 patients in each group completed the trial (12 months). The patients were generally suffering from mild to moderate HF (NYHA Class 1, 29.5%; Class 2, 50.5%; Class 3, 16%; and Class 4, 4%). RESULTS: Over the study period, intervention patients showed significant (P < 0.05) improvements in a range of summary outcome measures [AUC (95% confidence limits)] including exercise tolerance [2-min walk test: 1607.2 (1474.9, 1739.5) m.month in intervention patients vs. 1403.3 (1256.5, 1549.8) in control patients], forced vital capacity [31.6 (30.8, 32.4) l.month in the intervention patients vs. 27.8 (26.8, 28.9) in control patients], health-related quality of life, as measured by the Minnesota living with heart failure questionnaire [463.5 (433.2, 493.9) unit.month in intervention patients vs. 637.5 (597.2, 677.7) in control patients; a lower score in this measure indicates better health-related quality of life]. The number of individual patients who reported adherence to prescribed medications was higher (P < 0.05) in the intervention group (85 vs. 35), as was adherence to lifestyle advice (75 vs. 29) at the final assessment (12 months). There was a tendency to have a higher incidence of casualty department visits by intervention patients, but a lower rate of hospitalization. CONCLUSIONS: The research provides clear evidence that the delivery of pharmaceutical care to patients with HF can lead to significant clinical and humanistic benefits.