Assessment of Total Ropivacaine Concentration in Blood after Bilateral Pecto-Intercostal Fascial Block Combined with Rectus Sheath Block in Cardiac Surgery Patients.

OBJECTIVES: Pecto-intercostal fascial block (PIFB) and rectus sheath block (RSB) have been combined to offer better analgesia for cardiac surgery patients, but safety of the analgesic protocol with a large volume of ropivacaine is uncertain. METHODS: This is a prospective observational study at Peking University People's Hospital to investigate the pharmacokinetic profile of ropivacaine after combined regional blocks. Patients undergoing elective cardiac surgery by a median sternotomy were enrolled to receive bilateral PIFB and RSB with 70 mL 0.3% ropivacaine (total dose 210 mg). Blood was sampled at 5, 10, 15, 30, 60, 90 and 120 mins after blocks. Total blood concentration of ropivacaine for patients were measured. RESULTS: Ten patients were enrolled and analyzed. The peak total ropivacaine concentration varied from 0.67 to 2.42 µg/mL. Time to reach the peak values mainly located between 10 and 30 mins after the performance. No patients had ropivacaine concentration values above toxic threshold (4.3 µg/mL), and there were no systemic toxicity symptoms during the perioperative period. CONCLUSIONS: PIFB combined with RSB in a general injection of 70 mL 0.3% ropivacaine does not give rise to toxic levels, and it is an effective and safe analgesic protocol for cardiac surgery patients.

Safety Assessment of Amino Acid Alkyl Amides as Used in Cosmetics.

The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the product use, formulation, and safety data of 115 amino acid alkyl amides, which function as skin and hair conditioning agents and as surfactants-cleansing agents in personal care products. Safety test data on dermal irritation and sensitization for the ingredients with the highest use concentrations, lauroyl lysine and sodium lauroyl glutamate, were reviewed and determined to adequately support the safe use of the ingredients in this report. The Panel concluded that amino acid alkyl amides are safe in the present practices of use and concentration in cosmetics, when formulated to be nonirritating.

Safety assessment of diethanolamides as used in cosmetics.

Cocamide diethanolamine (DEA) and some of the other diethanolamides are mainly used as surfactant foam boosters or viscosity increasing agents in cosmetics, although a few are reported to be used as hair and skin conditioning agents, surfactant-cleansing or surfactant-emulsifying agents, or as an opacifying agent. The Cosmetic Ingredient Review (CIR) Expert Panel considered new data and information from previous CIR reports to assess the concerns about the potential for amidases in human skin to convert these diethanolamides into DEA and the corresponding fatty acids. The Expert Panel concluded that these diethanolamides are safe as used when formulated to be nonirritating and when the levels of free DEA in the diethanolamides do not exceed those considered safe by the Panel. The Panel also recommended that these ingredients not be used in cosmetic products in which N-nitroso compounds can be formed.

Ultrasound assessment of cranial spread during caudal blockade in children: effect of the speed of injection of local anaesthetics.

BACKGROUND: Despite caudal blockade being the most widely used regional anaesthetic procedure for infants and children undergoing subumbilical surgery, the question whether the injection velocity of the local anaesthetic itself affects its spread in the epidural space has not yet been investigated. Thus, the aim of the present study was to measure the cranial spread of caudally administered local anaesthetics in infants and children by means of real-time ultrasonography, with a special focus on comparing the effect of using two different speeds of injection. METHODS: Fifty ASA I-II infants and children, aged up to 6 yr, weighing up to 25 kg, undergoing subumbilical surgery, were enrolled in this prospective, randomized, observer-blinded study. Caudal blockade was performed under ultrasound observation using ropivacaine 1 ml kg(-1) 0.2% or 0.35% and an injection given at either 0.25 ml s(-1) or 0.5 ml s(-1), respectively. RESULTS: Ultrasound observation of the local anaesthetic flow and the extent of cranial spread was possible in all patients. All caudal blocks were considered successful, and all surgical procedures could be completed without any indications of insufficient analgesia. No statistically significant difference could be observed between the two injection speeds regarding the cranial spread of the local anaesthetic in the epidural space. CONCLUSIONS: The main finding of the present study is that the speed of injection of the local anaesthetic does not affect its cranial spread during caudal blockade in infants and children. Therefore, the prediction of the cranial spread of the local anaesthetic, depending on the injection speed, is not possible.

Ultrasound assessment of cranial spread during caudal blockade in children: the effect of different volumes of local anaesthetics.

BACKGROUND: Despite the large amount of literature on caudal anaesthesia in children, the issue of volume of local anaesthetics and cranial spread is still not settled. Thus, the aim of the present prospective randomized study was to evaluate the cranial spread of caudally administered local anaesthetics in children by means of real-time ultrasound, with a special focus on the effects of using different volumes of local anaesthetics. METHODS: Seventy-five children, 1 month to 6 yr, undergoing inguinal hernia repair or more distal surgery were randomized to receive a caudal block with 0.7, 1.0, or 1.3 ml kg(-1) ropivacaine. The cranial spread of the local anaesthetic within the spinal canal was assessed by real-time ultrasound scanning; the absolute cranial segmental level and the cranial level relative to the conus medullaris were determined. RESULTS: All the blocks were judged to be clinically successful. A significant correlation was found between the injected volume and the cranial level reached by the local anaesthetic both with regards to the absolute cranial segmental level and the cranial level relative to the conus medullaris. CONCLUSIONS: The main finding of the present study was positive, but numerically small correlation between injected volumes of local anaesthetic and the cranial spread of caudally administered local anaesthetics. Therefore, the prediction of the cranial spread of local anaesthetic, depending on the injected volume of the local anaesthetic, was not possible. EudraCT Number: 2008-007627-40.

Assessment of an 18F-labeled phosphoramidate peptidomimetic as a new prostate-specific membrane antigen-targeted imaging agent for prostate cancer.

UNLABELLED: Prostate-specific membrane antigen (PSMA) is a transmembrane protein commonly found on the surface of late-stage and metastatic prostate cancer and a well-known imaging biomarker for staging and monitoring therapy. Although (111)In-labeled capropmab pendetide is the only approved agent available for PSMA imaging, its clinical use is limited because of its slow distribution and clearance that leads to challenging image interpretation. A small-molecule approach using radiolabeled urea-based PSMA inhibitors as imaging agents has shown promise for prostate cancer imaging. The motivation of this work is to explore phosphoramidates as a new class of potent PSMA inhibitors to develop more effective prostate cancer imaging agents with improved specificity and clearance properties. METHODS: N-succinimidyl-4-(18)F-fluorobenzoate ((18)F-SFB) was conjugated to S-2-((2-(S-4-amino-4-carboxybutanamido)-S-2-carboxyethoxy)hydroxyphosphorylamino)-pentanedioic acid (Phosphoramidate (1)), yielding S-2-((2-(S-4-(4-(18)F-fluorobenzamido)-4-carboxybutanamido)-S-2-carboxyethoxy)hydroxyphosphorylamino)-pentanedioic acid (3). In vivo studies were conducted in mice bearing either LNCaP (PSMA-positive) or PC-3 (PSMA-negative) tumors. PET images were acquired at 1 and 2 h with or without a preinjection of a nonradioactive version of the fluorophosphoramidate. Tissue distribution studies were performed at the end of the 2 h imaging sessions. RESULTS: Phosphoramidate (1) and its fluorobenzamido conjugate (2) were potent inhibitors of PSMA (inhibitory concentration of 50% [IC(50)], 14 and 0.68 nM, respectively). PSMA-mediated tumor accumulation was noted in the LNCaP versus the PC-3 tumor xenografts. The LNCaP tumor uptake was also blocked by the administration of nonradioactive (2) prior to imaging studies. With the exception of the kidneys, tumor-to-tissue and tumor-to-blood ratios were greater than 5:1 at 2 h. The strong kidney uptake may be due to the known PSMA expression in the mouse kidney, because significant reduction (>6-fold) in kidney activity was seen in mice injected with (2). CONCLUSION: (18)F-labeled phosphoramidate (3) is a representative of a new class of PSMA targeting peptidomimetic molecules that shows great promise as imaging agents for detecting PSMA+ prostate tumors.

High-performance liquid chromatography using UV detection for the simultaneous quantification of ropivacaine and bupivacaine in human plasma.

A specific high-performance liquid chromatography assay coupled with UV detection has been developed and validated for the simultaneous determination of ropivacaine and bupivacaine in human plasma. A liquid-liquid back extraction procedure was used to increase specificity, and very good and consistent recoveries were obtained: 93%-95% for ropivacaine and 90%-96% for bupivacaine. The lowest limit of quantification was 4 and 8 ng/mL for ropivacaine and bupivacaine, respectively. The method was sensitive, reproducible (coefficient of variation

Bimatoprost/timolol: a review of its use in glaucoma and ocular hypertension.

Topically administered bimatoprost 0.03%/timolol 0.5% ophthalmic solution (bimatoprost/timolol: Ganfort) comprises the synthetic prostamide bimatoprost (structurally related to prostaglandin F2 alpha) and the beta-adrenergic receptor antagonist timolol. Bimatoprost/timolol (one drop administered in the affected eye[s] once daily in the morning or evening) is an effective and well tolerated fixed combination for lowering intra-ocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension (OHT), including individuals uncontrolled on monotherapy with a beta-adrenergic receptor antagonist or prostaglandin analogue/prostamide.

Taranabant, a novel cannabinoid type 1 receptor inverse agonist.

Merck & Co Inc is developing the cannabinoid receptor type 1 inverse agonist taranabant for the potential treatment of obesity and nicotine dependence. By October 2006, the drug had entered phase III trials for obesity, and by May 2008, a phase II study of taranabant as an aid to smoking cessation in chronic cigarette smokers had been completed.

Fluorescence-enhanced europium-diethylenetriaminepentaacetic (DTPA)-monoamide complexes for the assessment of renal function.

Real-time, noninvasive assessment of glomerular filtration rate (GFR) is essential not only for monitoring critically ill patients at the bedside, but also for staging and monitoring patients with chronic kidney disease. In our pursuit to develop exogenous luminescent probes for dynamic optical monitoring of GFR, we have prepared and evaluated Eu(3+) complexes of several diethylenetriamine pentaacetate (DTPA)-monoamide ligands bearing molecular "antennae" to enhance metal fluorescence via intramolecular ligand-metal fluorescence resonance energy transfer process. The results show that Eu-DTPA-monoamide complex 18b, which contains a quinoxanlinyl antenna, exhibits large (ca. 2700-fold) Eu(3+) fluorescence enhancement. Indeed, complex 18b exhibits the highest fluorescent enhancement observed thus far in the DTPA-type metal complexes. The renal clearance property was assessed using the corresponding radioactive (111)In complex 18a, and the data suggest that this complex clears via a complex mechanism that includes glomerular filtration.

Sensitive bioassay of bupivacaine in human plasma by liquid-chromatography-ion trap mass spectrometry.

A sensitive high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS-MS) method, using an ion trap spectrometer, was developed for quantitation of bupivacaine in human plasma. Bupivacaine and an internal standard (ropivacaine) were extracted in a single step from 100 microL of alkalinized plasma with diethyl-ether. The mobile phase consisted of acetonitrile with 0.1% formic acid (50:50, v/v), and was delivered at a flow rate of 0.3 mL/min. The effluent was detected by MS-MS in positive ion mode. Ionisation was performed, using an electrospray ion source, operating at 200 degrees C. The selected reaction monitoring transitions m/z 289-->m/z 140 and m/z 275-->m/z 126 were chosen for bupivacaine and ropivacaine, respectively. Calibration curves were linear over the concentration range of 3.90-500 microg/L with determination coefficients >0.996. The method is accurate (bias <10%) and reproducible (intra-assay and inter-assay precision <15%), with a quantitation limit of 3.90 microg/L, using only 100 microL of plasma. The high specificity and sensitivity, achieved by this fast method (total run-time <3 min), allowed the determination of bupivacaine plasma levels in pediatric patients, following epidural administration of bupivacaine.

Ropivacaine.

Ropivacaine (Naropin, AstraZeneca) is a long-acting amide local anaesthetic released for clinical use in 1996. Similar to bupivacaine, ropivacaine is equally effective for s.c. infiltration, epidural and peripheral nerve block for surgery, obstetric and post-operative analgesia. Ropivacaine differs from most other amide-type local anaesthetics in that it is marketed as a pure S-enantiomer, instead of as a racemate. This feature improves the safety of ropivacaine, and, indeed, studies have shown ropivacaine to have less cardiovascular and CNS toxicity than bupivacaine. Ropivacaine is nearly identical to bupivacaine in onset, quality and duration of sensory block, but it produces less motor block. Whether or not the motor sparing effect of ropivacaine is due to a lower relative potency compared to bupivacaine is a matter of intense debate. Despite a better safety profile, the increased cost of ropivacaine may limit its clinical utility.