Variability in perfusion conditions and set-up parameters used in ex vivo human placenta models: A literature review.

The ex vivo human placenta perfusion model has proven to be clinically relevant to study transfer- and fetal exposure of various drugs. Although the method has existed for a long period, the setup of the perfusion model has not been generalized yet. This review aims to summarize the setups of ex vivo placental perfusion models used to examine drug transfer across the placenta to identify generalized properties and differences across setups. A literature search was carried out in PubMed September 26, 2022. Studies were labeled as relevant when information was reported, between 2000 and 2022, on the setups of ex vivo placental perfusion models used to study drug transfer across the placenta. The placenta perfusion process, and the data extraction, was divided into phases of preparation, control, drug, and experimental reflecting the chronological timeline of the different phases during the entire placental perfusion process. 135 studies describing an ex vivo human placental perfusion experiment were included. Among included studies, the majority (78.5%) analyzed drug perfusion in maternal to fetal direction, 18% evaluated bi-directional drug perfusion, 3% under equilibrium conditions, and one study investigated drug perfusion in fetal to maternal direction. This literature review facilitates the comparison of studies that employ similar placenta perfusion protocols for drug transfer studies and reveals significant disparities in the setup of these ex vivo placental perfusion models. Due to interlaboratory variability, perfusion studies are not readily comparable or interchangeable. Therefore, a stepwise protocol with multiple checkpoints for validating placental perfusion is needed.

Pharmacy compounded pilocarpine: An adequate solution to overcome shortage of pilogel® discs for sweat testing in patients with cystic fibrosis.

To respond to shortage of pilocarpine discs due to CE-licensing problems a pharmacy compounded pilocarpine HCL solution was developed and validated for use in CF diagnosis. The aim of this study was to compare the results from a pharmacy compounded pilocarpine HCL solution versus Pilogel® discs for the measurements of sweat chloride concentrations. Ten pediatric and adult patients with CF underwent a sweat test using both Pilogel® discs and pilocarpine HCL solution. The average difference between both methods was -3.25 mmol/L (95% Limits of Agreement: -7.19 [95% CI: -9.19;-5.19] and 0.69 [95% CI: -1.31;2.69] mmol/L. Passing-Bablok regression showed that zero was enclosed with the 95% CI of the calculated intercept (0.15 [95% CI: -1.70;1.42] mmol/L). These data show a good agreement in chloride concentrations obtained using the two pilocarpine products. Therefore, the pharmacy compounded pilocarpine HCL solution can be used as an alternative for Pilogel® discs during times of shortage.

The Pharmacokinetics and Target Attainment of Antimicrobial Drugs Throughout Pregnancy: Part III Non-penicillin and Non-cephalosporin Drugs.

INTRODUCTION: Understanding the pharmacokinetics (PK) of antimicrobial drugs in pregnant women is crucial to provide effective and safe treatment. This study is part of a series that systematically reviews literature on the PK and analyzes if, based on the changed PK, evidence-based dosing regimens have been developed for adequate target attainment in pregnant women. This part focusses on antimicrobials other than penicillins and cephalosporins. METHODS: A literature search was conducted in PubMed according to the PRISMA guidelines. Search strategy, study selection, and data extraction were independently performed by two investigators. Studies were labeled as relevant when information on the PK of antimicrobial drugs in pregnant women was available. Extracted parameters included bioavailability for oral drugs, volume of distribution (Vd) and clearance (CL), trough and peak drug concentrations, time of maximum concentration, area under the curve and half-life, probability of target attainment, and minimal inhibitory concentration (MIC). In addition, if developed, evidence-based dosing regimens were also extracted. RESULTS: Of the 62 antimicrobials included in the search strategy, concentrations or PK data during pregnancy of 18 drugs were reported. Twenty-nine studies were included, of which three discussed aminoglycosides, one carbapenem, six quinolones, four glycopeptides, two rifamycines, one sulfonamide, five tuberculostatic drugs, and six others. Eleven out of 29 studies included information on both Vd and CL. For linezolid, gentamicin, tobramycin, and moxifloxacin, altered PK throughout pregnancy, especially in second and third trimester, has been reported. However, no target attainment was studied and no evidence-based dosing developed. On the other hand, the ability to reach adequate targets was assessed for vancomycin, clindamycin, rifampicin, rifapentine, ethambutol, pyrazinamide, and isoniazid. For the first six mentioned drugs, no dosage adaptations during pregnancy seem to be needed. Studies on isoniazid provide contradictory results. CONCLUSION: This systematic literature review shows that a very limited number of studies have been performed on the PK of antimicrobials drugs-other than cephalosporins and penicillins-in pregnant women.

Highly Variable Paracetamol Pharmacokinetics After Multiple Oral Dosing in Frail Older People: A Population Pharmacokinetic Analysis.

INTRODUCTION: Paracetamol pharmacokinetics (PK) is highly variable in older fit adults after intravenous administration. Frailty and oral administration likely result in additional variability. The aim was to determine oral paracetamol PK and variability in geriatric inpatients. METHODS: A population PK analysis, using NONMEM 7.2, was performed on 245 paracetamol samples in 40 geriatric inpatients (median age 87 [range 80-95] years, bodyweight 66.4 [49.3-110] kg, 92.5% frail [Edmonton Frail Scale]). All subjects received paracetamol 1000 mg as tablet (72.5%) or granulate (27.5%) three times daily. Simulations of dosing regimens (1000 mg every 6 hours [q6h] or q8h) were performed to determine target attainment, using mean steady-state concentration (Css-mean) of 10 mg/L as target. RESULTS: A one-compartment model with first order absorption and lag time best described the data. The inter-individual variability was high, with absorption rate constant containing the highest variability. The inter-individual variability could not be explained by covariates. Simulations of 1000 mg q6h and q8h resulted in a Css-mean of 10.8 [25-75th percentiles 8.2-12.7] and 8.13 [6.3-9.6] mg/L, respectively, for the average geriatric inpatient. The majority of the population remained off-target (22.2% [q6h] and 52.2% [q8h] <8 mg/L; 31.3 [q6h] and 7.6% [q8h] >12 mg/L). CONCLUSION: A population of average geriatric inpatients achieved target Css-mean with paracetamol 1000 mg q6h, while q8h resulted in underexposure for the majority of them. Due to high unexplained variability, a relevant proportion remained either above or below the target concentration of 10 mg/L. Research focusing on PK, efficacy and safety is needed to recommend dosing regimens.

Population Pharmacokinetic Modeling of Acetaminophen and Metabolites in Children After Cardiac Surgery With Cardiopulmonary Bypass.

Children undergoing cardiac surgery often receive acetaminophen (paracetamol) as part of their postoperative pain treatment. To date, there is no information on the pharmacokinetics (PK) of acetaminophen in this special population, even though differences, as a result of altered hemodynamics and/or use of cardiopulmonary bypass, may be anticipated. Therefore, the aim of this study was to investigate the PK of intravenous acetaminophen in children after cardiac surgery with cardiopulmonary bypass. In the study, both children with and without Down syndrome were included. A population PK analysis, using NONMEM 7.2, was performed based on 161 concentrations of acetaminophen, acetaminophen sulfate, acetaminophen glucuronide, and oxidative metabolites from 17 children with Down syndrome and 13 children without Down syndrome of a previously published study (median age, 177 days [range, 92-944], body weight, 6.1 kg [4.0-12.9]). All children received 3 intravenous acetaminophen doses of 7.5 mg/kg (<10 kg) or 15 mg/kg (≥10 kg) at 8-hour intervals after cardiac surgery. For acetaminophen and its metabolites, 1-compartment models were identified. Clearance of acetaminophen and metabolites increased linearly with body weight. Acetaminophen clearance in a typical child of 6.1 kg is 0.96 L/h and volume of distribution 7.96 L. Down syndrome did not statistically significantly impact any of the PK parameters for acetaminophen, nor did any other remaining covariate. When comparing the PK parameters of acetaminophen in children after cardiac surgery with cardiopulmonary bypass with those from children of the same age following noncardiac surgery reported in the literature, clearance of acetaminophen was lower and volume of distribution higher.

Population pharmacokinetic modelling of intravenous paracetamol in fit older people displays extensive unexplained variability.

AIMS: Paracetamol is the analgesic most used by older people. The physiological changes occurring with ageing influence the pharmacokinetics (PK) of paracetamol and its variability. We performed a population PK-analysis to describe the PK of intravenous (IV) paracetamol in fit older people. Simulations were performed to illustrate target attainment and variability of paracetamol exposure following current dosing regimens (1000 mg every 6 h, every 8 h) using steady-state concentration (Css-mean ) of 10 mg l-1 as target for effective analgesia. METHODS: A population PK-analysis, using NONMEM 7.2, was performed based on 601 concentrations of paracetamol from 30 fit older people (median age 77.3 years, range [61.8-88.5], body weight 79 kg [60-107]). All had received an IV paracetamol dose of 1000 mg (over 15 min) after elective knee surgery. RESULTS: A two-compartment PK-model best described the data. Volume of distribution of paracetamol increased exponentially with body weight. Clearance was not influenced by any covariate. Simulations of the standardized dosing regimens resulted in a Css of 9.2 mg l-1 and 7.2 mg l-1 , for every 6 h and every 8 h respectively. Variability in paracetamol PK resulted in Css above 5.4 and 4.1 mg l-1 , respectively, in 90% of the population and above 15.5 and 11.7, respectively, in 10% at these dosing regimens. CONCLUSIONS: The target concentration was achieved in the average patient with 1000 mg every 6 h, while every 8 h resulted in underdosing for the majority of the population. Furthermore, due to a large (unexplained) interindividual variability in paracetamol PK a relevant proportion of the fit older people remained either under- or over exposed.

Therapeutic Drug Monitoring in Neonates: What Makes them Unique?

INTRODUCTION: Therapeutic drug monitoring (TDM) refers to the interpretation of quantified drug concentrations in strategically timed samples of bodily fluids, with the aim to maximize therapeutic benefit, while minimizing toxicity. In essence, TDM criteria for neonates are similar to those for adults, but specific issues should be considered. This review focusses on the relevance of these specific issues: larger variability in pharmacokinetics (PK), and non-PK related factors, sampling opportunities, analytical techniques, therapeutic range. Specific issues: Larger variability in PK, and non-PK related factors in neonates compared to adults result in a less clear relation between the administered dose and the concentration measured. Sophisticated dosing regimens derived from population PK-models can partly overcome this variability, thereby reducing the need for TDM. Dosing can be further individualized using Bayesian forecasting as a tool for TDM. Besides PK related factors, concentrations of endogenous substances (e.g. immunoglobulin A, plasma protein) in neonates differ from those in adults, which may complicate interpretation of measured drug concentrations. Blood sampling opportunities in neonates are limited by the small blood volume and the need to minimize painful procedures. Dried blood spot sampling may be less invasive. This method has been facilitated by more sensitive analytical techniques, such as chromatography followed by mass spectrometry. For the same reason, saliva is gaining attention as an alternative non-invasive bodily fluid. Lastly, reference values for therapeutic ranges of drugs in neonates are mostly adapted from adult studies, although pharmacodynamics may be quite different in neonates. This review concludes with recommendations for future research on these specific issues.

Intravenous Paracetamol Dosing Guidelines for Pain Management in (pre)term Neonates Using the Paediatric Study Decision Tree.

BACKGROUND: Intravenous paracetamol (acetaminophen) has not been licensed for analgesia in preterm neonates or infants < 2 years, respectively, in Europe and the United States. A variety of dosing regimens is therefore used off-label. Because evidence supports the use of the same target mean steady state paracetamol concentration (Cssmean, 9-11 mg/L) for pain relief in neonates compared to older children and adults, dosing regimens based on this Cssmean were evaluated in a two-step approach. METHODS: First, a systematic search was performed to provide pharmacokinetic (PK)-based dosing guidelines for pain in neonates (with subsequent searches on safety in these papers). Second, concentration-time profiles based on these dosing guidelines were generated to provide a dosing advice for paracetamol to treat neonatal pain. RESULTS: Of 2334 potentially relevant articles, 9 studies were included. For typical term neonates, dosages specified in packaging (labels) resulted in Cssmean below target (7.65 mg/L), while dosages from investigator-initiated studies resulted in either a Cssmean above (15.31), or around the target (11.78 and 10.21) for (pre)term neonates >32 weeks. Only one study suggested a dosing resulting in a tailored concentration (8.7) in preterm neonates <32 weeks. CONCLUSION: A loading dose 20 mg/kg, followed by 10 mg/kg/6h is recommended for 32-44 weeks' neonates, which is supported by short-term safety. For neonates < 32 weeks, a loading dose of 12 mg/kg and a maintenance dose of 6mg/kg/6h seems to lead to the target Cssmean, though additional clinical studies are needed to support its safety.

Case Reports. Chronic and acute Aspergillus meningitis.

Cerebral aspergillosis usually occurs in severely immunocompromized hosts, is difficult to diagnose, and has a poor prognosis. After 14 months of chronic meningitis, ventriculitis, choroid plexitis, and lumbar arachnoiditis, which was complicated by acute hydrocephalus, Aspergillus, suspected to be from the candidus group, was isolated from the cerebrospinal fluid (CSF) of a previously healthy man. Thereafter Aspergillus antigen was found in stored plasma and CSF samples. He was treated with voriconazole and itraconazole. In a haemodialysis patient affected by an acute meningococcal meningitis, following a 3-day symptom-free interval, symptoms and signs of acute meningitis had reappeared and were unresponsive to a broad antimicrobial coverage. However, they resolved within 5 days after liposomal amphotericin B treatment had been started. From his CSF Aspergillus-DNA was identified and Aspergillus fumigatus isolated by culture. These two different clinical cases show that Aspergillus-DNA and antigen detection tests represent an advance in the diagnosis and liposomal amphotericin B, voriconazole, and itraconazole are an advance in the treatment of Aspergillus meningitis.

Temporal arteritis associated with Chlamydia pneumoniae DNA detected in an artery specimen.

Temporal arteritis is a clinical manifestation of giant cell arteritis. The etiology of this disease is still unknown. Sudden onset and wide variations of incidence are reported in different parts of the world. Acute onset is often associated with flu-like symptoms, indicating that infectious factors probably act as precipitating agents. We describe a 72-year-old man referred to our department in January 1999 for unremitting fever and temporal arteritis associated with Chlamydia pneumoniae infection.

The role of the clinical nurse specialist in the development of a domestic violence program.

In the demanding and ever-changing world of healthcare, CNSs are constantly challenged to define their practice and contributions to the organization. This article describes the multifaceted role of the CNS in the development of an innovative hospital-wide domestic violence program. The strategic use of the CNS, primarily as an organizational consultant, illustrates how nursing practice is improved when the organization is the primary focus.

[Exposure to the risk of the manual lifting of patients and the results of a clinical study in 4 hospital establishments of northern Italy]. / Esposizione al rischio di movimentazione manuale dei pazienti e risultati dell'indagine clinica in quattro aziende ospedaliere del Nord Italia.

The paper reports the results of a study carried out in four hospitals in northern Italy to assess exposure to patient handling and the consequent risks for the lumbar region of the spine. The methods proposed by the EPM Research Unit were used. Altogether, in the four hospitals there were 148 wards and 5596 staff. Of these, 34 wards and 510 workers were examined. The results of exposure assessment showed that the obstetrics departments had negligible risk (MAPO Index 0-1.5), urology and general surgery departments an intermediate risk (MAPO Index 1.51-5.0), while the departments of medicine, orthopaedics, neurology and rehabilitation had high risks (MAPO Index > 5.0). Of the 510 workers who underwent physical and anamnestic assessment for spinal disorders, 44% worked in the departments of medicine, which are known to have a high risk The prevalence of subjects who reported episodes of acute low back pain in the last 12 months (11.4%) was 5 times that of a group of workers not exposed to manual load handling (2.3%). Analysis of the same disorder referred to each job showed higher prevalences in the non-nursing staff (technical 25%, general 27%). The frequency of degenerative disorders of the lumbar spine was slightly lower than the figure for the country as a whole (6.7%). It is clear that measures for improvement of the environment are required aimed particularly at installing aids and staff training (for the specific risk factor), also so as to better manage the reallocation of workers judged unfit for patient handling who, in the group under study, were 5%.

Gibbilimbols A-D, cytotoxic and antibacterial alkenylphenols from Piper gibbilimbum.

Fractionation of the petroleum ether extract from the leaves of Piper gibbilimbum collected in Papua New Guinea afforded four new alkenylphenols, gibbilimbols A-D (1-4). The structures of the isolates were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR spectroscopy. Gibbilimbols A-D were found to be toxic to brine shrimp with an LC50 of approximately 5 microg/mL. Gibbilimbols A-D were further found to be cytotoxic toward KB nasopharyngal carcinoma cells (ED50 7.8-2.1 microg/mL). All isolates also showed antibacterial activity toward Staphylococcus epidermidis and Bacillus cereus.

Severe pneumonia in pregnancy three months after resolution of cutaneous zoster.

A 22 weeks pregnant women was affected by a life-threatening pneumonia and a paresis of the proximal muscles with cerebrospinal fluid pleocytosis. Her past medical history had been unremarkable except for recurrent episodes of paraumbilical herpes zoster. The clinical findings suggested a dissemination of varicella-zoster virus without skin lesions. Acyclovir was added to the therapy, and the clinical picture began to improve. Varicella-zoster virus DNA was detected in placental tissue by DNA-hybridisation analysis.