Fospropofol disodium versus propofol for long-term sedation during invasive mechanical ventilation: A pilot randomized clinical trial.

STUDY OBJECTIVE: Fospropofol disodium is a propofol prodrug that is water-soluble and has a reduced risk of bacterial contamination and hypertriglyceridemia compared with propofol. Prior to implementing a large randomized trial, we investigated the feasibility, initial efficacy, and safety of fospropofol disodium compared with propofol in long-term mild-to-moderate sedation in intensive care units (ICUs). DESIGN: Single-centered, prospective, unblind, randomized, parallel-group clinical trial. SETTING: The general ICU of university-affiliated teaching hospital. PATIENTS: Adult patients (n = 60) expected to have mechanical ventilation for >24 h were enrolled and randomly assigned to the fospropofol or propofol group. INTERVENTIONS: The fospropofol group received continuous fospropofol disodium infusions and the propofol group received continuous propofol infusions. The sedation goal was a score of -3 to 0 on the Richmond Agitation and Sedation Scale (RASS). MEASUREMENTS: The primary outcome was the percentage of time spent in the target sedation range without rescue sedation. Safety outcomes were based on adverse events. Blood samples were collected to measure formate concentration in plasma. MAIN RESULTS: The median dose was 4.33 (IQR, 3.08-4.94) mg/kg/h in the fospropofol group and 1.96 (IQR, 1.44-2.94) mg/kg/h in the propofol group. The median percentage of time spent in the target RASS range without rescue sedation was identical in both groups, with 83.33% (IQR, 74.43%-100.00%) in the fospropofol group and 83.33% (IQR, 77.45%-100.00%) in the propofol group (p = 0.887). At least one adverse event was identifed in 23 (76.7%) fospropofol patients and 27 (90.0%) propofol patients. The most common adverse events were tachycardia and hypotension. No paresthesia, catheter-related bloodstream infection or propofol infusion syndrome in both groups was reported. Three patients in the fospropofol group had mild hypertriglyceridemia, and nine patients in propofol group had hypertriglyceridemia (mild in eight patients and moderate in one patient) (10% versus 30%, p = 0.104). The formate concentration in plasma was very low, and no significant difference was identified at any time point between the two groups. CONCLUSIONS: Fospropofol disodium appears to be a feasible, effective and safe sedative for patients receiving invasive mechanical ventilation with long-term sedation.

In Vivo Photoadduction of Anesthetic Ligands in Mouse Brain Markedly Extends Sedation and Hypnosis.

Photoaffinity ligands are best known as tools used to identify the specific binding sites of drugs to their molecular targets. However, photoaffinity ligands have the potential to further define critical neuroanatomic targets of drug action. In the brains of WT male mice, we demonstrate the feasibility of using photoaffinity ligands in vivo to prolong anesthesia via targeted yet spatially restricted photoadduction of azi-m-propofol (aziPm), a photoreactive analog of the general anesthetic propofol. Systemic administration of aziPm with bilateral near-ultraviolet photoadduction in the rostral pons, at the border of the parabrachial nucleus and locus coeruleus, produced a 20-fold increase in the duration of sedative and hypnotic effects compared with control mice without UV illumination. Photoadduction that missed the parabrachial-coerulean complex also failed to extend the sedative or hypnotic actions of aziPm and was indistinguishable from nonadducted controls. Paralleling the prolonged behavioral and EEG consequences of on target in vivo photoadduction, we conducted electrophysiologic recordings in rostral pontine brain slices. Using neurons within the locus coeruleus to further highlight the cellular consequences of irreversible aziPm binding, we demonstrate transient slowing of spontaneous action potentials with a brief bath application of aziPm that becomes irreversible on photoadduction. Together, these findings suggest that photochemistry-based strategies are a viable new approach for probing CNS physiology and pathophysiology.SIGNIFICANCE STATEMENT Photoaffinity ligands are drugs capable of light-induced irreversible binding, which have unexploited potential to identify the neuroanatomic sites of drug action. We systemically administer a centrally acting anesthetic photoaffinity ligand in mice, conduct localized photoillumination within the brain to covalently adduct the drug at its in vivo sites of action, and successfully enrich irreversible drug binding within a restricted 250 µm radius. When photoadduction encompassed the pontine parabrachial-coerulean complex, anesthetic sedation and hypnosis was prolonged 20-fold, thus illustrating the power of in vivo photochemistry to help unravel neuronal mechanisms of drug action.

Propofol directly binds to and inhibits TLR7.

Sedatives/anesthetics are important medical tools to facilitate medical care and increase patients' comfort. Increasingly, there is recognition that sedatives/anesthetics can modulate immune functions. Toll-like receptors (TLRs) are major pattern recognition receptors involved in the recognition of microbial components. TLR7 recognizes single-strand RNA virus such as influenza and SARS-CoV2 viruses and initiates interferon (IFN) responses. IFN production triggered by TLR7 stimulation is a critical anti-viral response. For example, patients with TLR7 variants including loss-of- function variants were associated with severe COVID-19. Taken together, it is important to determine if sedatives/anesthetics mitigate TLR7 function. We have previously showed that TLR7-mediated activation was not affected by volatile anesthetics. However, we found that propofol attenuated TLR7 activation among intravenous sedatives in the reporter assay. TLR7 agonist R837 stimulation increased TNF-α, IL-1ß, IL-6, IL-10, and IFN-ß mRNA levels in bone marrow-derived dendritic cells, while these levels were attenuated by propofol. Our murine lung slice experiments showed that propofol attenuated IFN production. R837 increased IFN-ß expression in the lungs, and propofol attenuated IFN-ß expression in an in vivo model of R837 intranasal instillation. We also found that propofol directly bound to and hindered its association of TLR7 with MyD88. Our analysis using fropofol, propofol derivative showed that the hydroxyl group in propofol was important for propofol-TLR7 interaction.

LMR-101, a novel derivative of propofol, exhibits potent anticonvulsant effects and possibly interacts with a novel target on γ-aminobutyric acid type A receptors.

OBJECTIVE: LMR-101 is a bisphenol derivative of propofol, a short-acting general anesthetic, which is also used to manage status epilepticus (SE). We evaluated the sedative and anticonvulsant effects of LMR-101 to discover its potential to manage epilepsy and SE in the clinic. METHODS: Comparative studies between LMR-101 and propofol were performed in mice to elucidate an appropriate dose range for LMR-101 that produced anticonvulsant effects without significant sedation. Then, the anticonvulsive efficacy for LMR-101 was evaluated using seizure models induced by pentylenetetrazol and (+)-bicuculline. The ability of LMR-101 to inhibit SE was assessed using a rat model of SE induced by pilocarpine. Radioligand binding assay profiles for LMR-101 were performed to evaluate the potential mechanisms of action underlying its anticonvulsant properties. RESULTS: In the mouse study, LMR-101 exhibited greater anticonvulsant and lesser sedative effect compared with propofol. LMR-101 completely inhibited pentylenetetrazol-induced seizures at a dose of 50 mg/kg and exhibited heavy sedation at 300 mg/kg. Propofol anesthetized all mice and only decreased the seizure rate at 25 mg/kg. LMR-101 also suppressed seizure behaviors evoked by (+)-bicuculline in mice in a dose-dependent manner. In the pilocarpine-induced SE model, LMR-101 significantly decreased the maximum seizure score and seizure duration in a dose-dependent manner. The median effective dose for LMR-101 was 14.30 mg/kg and 121.87 mg/kg to prevent and inhibit sustained SE, respectively. In binding assays, LMR-101 primarily inhibited tert-[35 S] butylbicyclophosphorothionate binding to γ-aminobutyric acid type A (GABAA ) receptors (half-maximal inhibitory concentration = 2.06 µmol·L-1 ), but it did not affect [3 H] flunitrazepam or [3 H] muscimol binding. SIGNIFICANCE: It is anticipated that LMR-101 might play an essential role in the clinical management of epilepsy and SE. LMR-101 also might bind to a novel target site on the GABAA receptor that is different from existing antiepileptic drugs. Further study of the mechanisms of action of LMR-101 would be of considerable value in the search for new active drug sites on GABAA receptors.

Mechanistic basis of propofol-induced disruption of kinesin processivity.

Propofol is a widely used general anesthetic to induce and maintain anesthesia, and its effects are thought to occur through impact on the ligand-gated channels including the GABAA receptor. Propofol also interacts with a large number of proteins including molecular motors and inhibits kinesin processivity, resulting in significant decrease in the run length for conventional kinesin-1 and kinesin-2. However, the molecular mechanism by which propofol achieves this outcome is not known. The structural transition in the kinesin neck-linker region is crucial for its processivity. In this study, we analyzed the effect of propofol and its fluorine derivative (fropofol) on the transition in the neck-linker region of kinesin. Propofol binds at two crucial surfaces in the leading head: one at the microtubule-binding interface and the other in the neck-linker region. We observed in both the cases the order-disorder transition of the neck-linker was disrupted and kinesin lost its signal for forward movement. In contrast, there was not an effect on the neck-linker transition with propofol binding at the trailing head. Free-energy calculations show that propofol at the microtubule-binding surface significantly reduces the microtubule-binding affinity of the kinesin head. While propofol makes pi-pi stacking and H-bond interactions with the propofol binding cavity, fropofol is unable to make a suitable interaction at this binding surface. Therefore, the binding affinity of fropofol is much lower compared to propofol. Hence, this study provides a mechanism by which propofol disrupts kinesin processivity and identifies transitions in the ATPase stepping cycle likely affected.

Fropofol prevents disease progression in mice with hypertrophic cardiomyopathy.

AIMS: Increased myofilament contractility is recognized as a crucial factor in the pathogenesis of hypertrophic cardiomyopathy (HCM). Direct myofilament desensitization might be beneficial in preventing HCM disease progression. Here, we tested whether the small molecule fropofol prevents HCM phenotype expression and disease progression by directly depressing myofilament force development. METHODS AND RESULTS: Force, intracellular Ca2+, and steady-state activation were determined in isolated trabecular muscles from wild-type (WT) and transgenic HCM mice with heterozygous human α-myosin heavy chain R403Q mutation (αMHC 403/+). αMHC 403/+ HCM mice were treated continuously with fropofol by intraperitoneal infusion for 12 weeks. Heart tissue was analysed with histology and real-time PCR of prohypertrophic and profibrotic genes. Fropofol decreased force in a concentration-dependent manner without significantly altering [Ca2+]i in isolated muscles from both WT and αMHC 403/+ HCM mouse hearts. Fropofol also depressed maximal Ca2+-activated force and increased the [Ca2+]i required for 50% activation during steady-state activation. In whole-animal studies, chronic intra-abdominal administration of fropofol prevented hypertrophy development and diastolic dysfunction. Chronic fropofol treatment also led to attenuation of prohypertrophic and profibrotic gene expression, reductions in cell size, and decreases in tissue fibrosis. CONCLUSIONS: Direct inhibition of myofilament contraction by fropofol prevents HCM disease phenotypic expression and progression, suggesting that increased myofilament contractile force is the primary trigger for hypertrophy development and HCM disease progression.

Identifying Drugs that Bind Selectively to Intersubunit General Anesthetic Sites in the α1ß3γ2 GABAAR Transmembrane Domain.

GABAA receptors (GABAARs) are targets for important classes of clinical agents (e.g., anxiolytics, anticonvulsants, and general anesthetics) that act as positive allosteric modulators (PAMs). Previously, using photoreactive analogs of etomidate ([3H]azietomidate) and mephobarbital [[3H]1-methyl-5-allyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid ([3H]R-mTFD-MPAB)], we identified two homologous but pharmacologically distinct classes of general anesthetic binding sites in the α1ß3γ2 GABAAR transmembrane domain at ß +-α - (ß + sites) and α +-ß -/γ +-ß - (ß - sites) subunit interfaces. We now use competition photolabeling with [3H]azietomidate and [3H]R-mTFD-MPAB to identify para-substituted propofol analogs and other drugs that bind selectively to intersubunit anesthetic sites. Propofol and 4-chloro-propofol bind with 5-fold selectivity to ß +, while derivatives with bulkier lipophilic substitutions [4-(tert-butyl)-propofol and 4-(hydroxyl(phenyl)methyl)-propofol] bind with ∼10-fold higher affinity to ß - sites. Similar to R-mTFD-MPAB and propofol, these drugs bind in the presence of GABA with similar affinity to the α +-ß - and γ +-ß - sites. However, we discovered four compounds that bind with different affinities to the two ß - interface sites. Two of these bind with higher affinity to one of the ß - sites than to the ß + sites. We deduce that 4-benzoyl-propofol binds with >100-fold higher affinity to the γ +-ß - site than to the α +-ß - or ß +-α - sites, whereas loreclezole, an anticonvulsant, binds with 5- and 100-fold higher affinity to the α +-ß - site than to the ß + and γ +-ß - sites. These studies provide a first identification of PAMs that bind selectively to a single intersubunit site in the GABAAR transmembrane domain, a property that may facilitate the development of subtype selective GABAAR PAMs.

An improved water-soluble prodrug of propofol with high molecular utilization and rapid onset of action.

Water-soluble prodrugs of propofol often carry an excess of propofol at the effective dose and have a slower onset of action. Sustained release of the original drug can result in propofol accumulation in the body after administration, causing delays in wakefulness. This situation causes the prodrug to lose the benefits of rapid onset and recovery from the effects of propofol. In the present study, HX0921 (sodium 2-(2-(2,6-diisopropylphenoxy)-2-oxoethoxy)acetate), an improved prodrug of propofol with high utilization of propofol and fast onset of action, was studied. The rate of propofol release from HX0921 was much faster than that from fospropofol (a marketed propofol prodrug) in rat plasma. The 50% effective dose (ED50) of propofol, HX0921 and fospropofol to induce anesthesia in rats was 5.78, 22.19 and 42.44 mg/kg, respectively. After administration at 2 × ED50, the onset time of anesthesia in the HX0921 group was significantly shorter than that in the fospropofol group (0.26 ±â€¯0.15 min vs. 2.24 ±â€¯0.35 min, P < 0.01) and the duration of anesthesia in the HX0921 group was also significantly shorter than that in the fospropofol group (22.35 ±â€¯4.05 min vs. 29.15 ±â€¯5.25 min, P < 0.01). These results suggest that the rapid onset and short action time of HX0921 was due to the rapid release and high molecular utilization of propofol carried by HX0921.

Newer propofol, ketamine, and etomidate derivatives and delivery systems relevant to anesthesia practice.

Drug discovery is the cornerstone of developments in the field of anesthesia. Each year, new drugs enter the market and possibly change clinical practice. The development of new anesthetics can be divided into two groups. One strategy is the discovery of a new type of drug with unique molecular structure, better clinical properties, and lesser side effects than the already existing drugs. Another strategy is changing the molecular structure of current clinically available anesthetics to create new drugs with better pharmacokinetic and pharmacodynamic properties. In this review, we describe the current developments of frequently used anesthetics, namely, propofol, etomidate, and ketamine. Alfaxalone is an old anesthetic with favorable properties such as hemodynamic and respiratory stability but lacks appropriate vehicle. New formulations with recently developed solvents together with this old anesthetic are created. Next to drug development, there is also a constant search for better delivery systems for the already available anesthetics. Following open-loop systems like TIVA, new closed-loop systems have entered the market. We also discuss about SEDASYS®-Computer-Assisted Personalized Sedation System, an automatic closed-loop delivery system that provides propofol sedation for endoscopic procedures.

Metabolic Profiles of Propofol and Fospropofol: Clinical and Forensic Interpretative Aspects.

Propofol is an intravenous short-acting anesthetic widely used to induce and maintain general anesthesia and to provide procedural sedation. The potential for propofol dependency and abuse has been recognized, and several cases of accidental overdose and suicide have emerged, mostly among the health professionals. Different studies have demonstrated an unpredictable interindividual variability of propofol pharmacokinetics and pharmacodynamics with forensic and clinical adverse relevant outcomes (e.g., pronounced respiratory and cardiac depression), namely, due to polymorphisms in the UDP-glucuronosyltransferase and cytochrome P450 isoforms and drugs administered concurrently. In this work the pharmacokinetics of propofol and fospropofol with particular focus on metabolic pathways is fully reviewed. It is concluded that knowing the metabolism of propofol may lead to the development of new clues to help further toxicological and clinical interpretations and to reduce serious adverse reactions such as respiratory failure, metabolic acidosis, rhabdomyolysis, cardiac bradyarrhythmias, hypotension and myocardial failure, anaphylaxis, hypertriglyceridemia, renal failure, hepatomegaly, hepatic steatosis, acute pancreatitis, abuse, and death. Particularly, further studies aiming to characterize polymorphic enzymes involved in the metabolic pathway, the development of additional routine forensic toxicological analysis, and the relatively new field of ''omics" technology, namely, metabolomics, can offer more in explaining the unpredictable interindividual variability.

Challenges of bringing a new sedative to market!

PURPOSE OF REVIEW: The current review examines the success and failures of the development of new hypnotic compounds for the human market. One of the important aspects is that one of the key present agents, propofol, is considered by many anaesthesiologists as 'the ideal'. However, all drugs have adverse or side-effects. RECENT FINDINGS: The last 30 years since the introduction of propofol has seen many new compounds evaluated; but as at the present time, only three agents may achieve a pivotal position in the market - fospropofol (a sedative agent which may have a role in endoscopic surgery); remimazolam (a short-acting benzodiazepine) whose development is also being focused on the sedation rather than anaesthesia market; and the pregnane steroid, alfaxalone (an anaesthetic agent first introduced in 1972, but withdrawn in 1984 because of adverse allergic reactions to the solvent, Cremophor EL) now solvented in a cyclodextrin. SUMMARY: Studies of these three agents thus far have shown that none of them has any major adverse side-effects; all have properties which warrant further clinical evaluation.

Verification of propofol sulfate as a further human propofol metabolite using LC-ESI-QQQ-MS and LC-ESI-QTOF-MS analysis.

BACKGROUND: Propofol (2,6-diisopropylphenol) is a water-insoluble, intravenous anesthetic that is widely used for the induction and maintenance of anesthesia as well as for endoscopic and pediatric sedation. After admission, propofol undergoes extensive hepatic and extrahepatic metabolism, including direct conjugation to propofol glucuronide and hydroxylation to 2,6-diisopropyl-1,4-quinol. The latter substance subsequently undergoes phase II metabolism, resulting in the formation of further metabolites (1quinolglucuronide, 4quinolglucuronide and 4quinol-sulfate). Further minor phase I propofol metabolites (2-(ω-propanol)-6-isopropylphenol and 2-(ω-propanol)-6-isopropyl-1,4-quinol)) are also described. Due to its chemical structure with the phenolic hydroxyl group, propofol is also an appropriate substrate for sulfation by sulfotransferases. METHODS: The existence of propofol sulfate was investigated by liquid chromatography electrospray ionization triple quadrupole mass spectrometry (LCESIQQQ-MS) and liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LCESI-QTOF-MS). A propofol sulfate reference standard was used for identification and method development, yielding a precursor at m/z 257 (deprotonated propofol sulfate) and product ions at m/z 177 (deprotonated propofol) and m/z 80 ([SO3]-). RESULTS: Propofol sulfate - a further phase II metabolite of propofol - was verified in urine samples by LC-ESI-QQQ-MS and LC-ESI-QTOF-MS. Analyses of urine samples from five volunteers collected before and after propofol-induced sedation verified the presence of propofol sulfate in urine following propofol administration, whereas ascertained concentrations of this metabolite were significantly lower compared with detected propofol glucuronide concentrations. CONCLUSIONS: The existence of propofol sulfate as a further phase II propofol metabolite in humans could be verified by two different detection techniques (LCESIQQQ-MS and LC-ESI-QTOFMS) on the basis of a propofol sulfate reference standard. Evaluation of the quantitative analyses of propofol sulfate imply that propofol sulfate represents a minor metabolite of propofol and is only slightly involved in human propofol clearance.

On the Horizon: The Future of Procedural Sedation.

Sedation plays an integral part in endoscopy. By achieving patient comfort, it allows for a better examination and enhances patient satisfaction. Various medications have been used, propofol being the current favorite. With emphasis on patient safety and quality of endoscopy, various new medications in different combinations are being used to achieve adequate sedation and not escalate the cost of the procedure. With the advent of newer medications and newer modalities to administer these medications, there is need for more specialized training for the endoscopist to feel comfortable while using these medications.

Activation and modulation of recombinant glycine and GABAA receptors by 4-halogenated analogues of propofol.

BACKGROUND AND PURPOSE: Glycine receptors are important players in pain perception and movement disorders and therefore important therapeutic targets. Glycine receptors can be modulated by the intravenous anaesthetic propofol (2,6-diisopropylphenol). However, the drug is more potent, by at least one order of magnitude, on GABAA receptors. It has been proposed that halogenation of the propofol molecule generates compounds with selective enhancement of glycinergic modulatory properties. EXPERIMENTAL APPROACH: We synthesized 4-bromopropofol, 4-chloropropofol and 4-fluoropropofol. The direct activating and modulatory effects of these drugs and propofol were compared on recombinant rat glycine and human GABAA receptors expressed in oocytes. Behavioural effects of the compounds were compared in the tadpole loss-of-righting assay. KEY RESULTS: Concentration-response curves for potentiation of homomeric α1, α2 and α3 glycine receptors were shifted to lower drug concentrations, by 2-10-fold, for the halogenated compounds. Direct activation by all compounds was minimal with all subtypes of the glycine receptor. The four compounds were essentially equally potent modulators of the α1ß3γ2L GABAA receptor with EC50 between 4 and 7 µM. The EC50 for loss-of-righting in Xenopus tadpoles, a proxy for loss of consciousness and considered to be mediated by actions on GABAA receptors, ranged from 0.35 to 0.87 µM. CONCLUSIONS AND IMPLICATIONS: We confirm that halogenation of propofol more strongly affects modulation of homomeric glycine receptors than α1ß3γ2L GABAA receptors. However, the effective concentrations of all tested halogenated compounds remained lower for GABAA receptors. We infer that 4-bromopropofol, 4-chloropropofol and 4-fluoropropofol are not selective homomeric glycine receptor modulators.

A forecast of relevant pediatric sedation trends.

PURPOSE OF REVIEW: Over the past decade, the field of pediatric sedation has benefited from contributions which include the introduction and update of policies, procedures, and guidelines regarding training, physiologic monitoring and delivery, the approval of new sedatives, the multispecialty collaborations intended to advance the field and the development of sedatives, and delivery systems. This review will explore new drug innovations as well as evolved formulations of already approved agents, unique sedative delivery systems, the clinical application of pharmacogenetics and will conclude with a reflection on the current and future trends and focus of pediatric sedation research. RECENT FINDINGS: In recent years, the number of diagnostic and therapeutic procedures performed on children in nonoperating room anesthetizing locations has exploded at a rate which has in many instances, outpaced the availability of anesthesiologists. Over the past decade, the search for safe and effective sedatives and delivery systems has been embraced by all sedation providers. Dexmedetomidine and fospropofol were recently introduced, along with a computer-assisted personalized sedation delivery system which empowers the patient to assist in his own sedation. The evolution of target-controlled infusion systems with both open and closed-loop design are intended to more precisely deliver sedation using pharmacokinetic models specific for each sedative. New formulations of propofol, ketamine, etomidate, and benzodiazepines are in development, all striving to improve predictability, safety, and recovery profile. Pharmacogenetics is being explored for its role in the effects of analgesics, sedatives, and local anesthetics. SUMMARY: As the demand for procedural sedation continues to expand, the sedation providers must continue to be creative in their search for novel, safe, effective, and efficient methods to deliver care. Approaching the field of sedation as a science is essential for the clinicians and researchers who strive to tailor the sedation to the patient and the procedure.

Efficacy and Safety of FospropofolFD Compared to Propofol When Given During the Induction of General Anaesthesia: A Phase II, Multi-centre, Randomized, Parallel-Group, Active-Controlled, Double-Blind, Double-Dummy Study.

The present phase II study aimed to compare the efficacy and safety of fospropofol disodium for injection (FospropofolFD ) and propofol when given during the induction of general anaesthesia in patients scheduled for elective surgery. FospropofolFD is a water-soluble prodrug of propofol. Approved by the Ethical Committee, 240 participants aged 18-65 years were equally randomly allocated to receive an intravenous bolus of FospropofolFD 20 mg/kg or propofol 2 mg/kg without any anaesthetic pre-treatment. The primary efficacy end-point was the sedation success rate within 5 min. after administering investigational drugs (the sedation success is defined as obtaining Modified Observer's Assessment of Alertness/Sedation scale score of 1). All the participants completed the induction and intubation within 25 min. after administration. The sedation success rates within 5 min. after administration of FospropofolFD 20 mg/kg and propofol 2 mg/kg were 94.50% versus 100% in the intention-to-treat population and 95.10% versus 100% in the per-protocol population, respectively. The non-inferiority test obtained a p-value less than 0.025, and the lower limits of the one-sided 97.5% confidence interval were more than -0.09. This meant that FospropofolFD 20 mg/kg was considered non-inferior to propofol 2 mg/kg for the primary efficacy end-point. Compared with propofol 2 mg/kg, FospropofolFD 20 mg/kg had a slower sedation efficacy. No serious adverse events were observed in the two groups. The sedation success rate within 5 min. after administration of FospropofolFD 20 mg/kg was non-inferior to propofol 2 mg/kg, and FospropofolFD 20 mg/kg can be used for the induction of general anaesthesia safely.

Adult procedural sedation: an update.

PURPOSE OF REVIEW: The increasing request for procedural sedation will create in the upcoming future the need for a specific training in delivering care to patients in a continuum of sedation, whose effects and adverse events are unpredictable. The main debate in the past years has been focused on using drugs that could have few adverse effects and could be considered well tolerated when administered by a nonanaesthesiologist. Propofol remains the most used drug for procedural sedation, but given its side-effects, its administration is limited and suggested only when an anaesthesiologist is available. The main studies recently appearing in the literature are focusing on the use of alternative drugs such as dexmedetomidine, remifentanil, fospropofol, ketofol and remimazolam. The current study is an overview of the different fields of procedural sedation, describing the evidence from the published studies and some upcoming studies. RECENT FINDINGS: Propofol is still considered as the drug of choice, and a recent study on its administration in the emergency department by nonanaesthesiologists has revealed a reduced number of adverse events. Dexmedetomidine is considered, at present, the most commonly used alternative to propofol, given its greater safety in terms of haemodynamic stability and lack of respiratory depression. Remifentanil has been suggested as the 'solo' drug during procedural sedation by target-controlled infusion, but it needs a controlled environment and skilled practitioners. Fosprofol and ketofol are new alternatives, but convincing studies that could support their wider use are absent. Remimazolam is another alternative whose efficacy is still to be determined. Most of the studies in the literature are debating on the training that the 'proceduralist' should undergo to deliver sedation safely and to manage any kind of adverse effect caused by it. SUMMARY: Recent studies on procedural sedation are still debating on the use of propofol by nonanaesthesiologists and are exploring the use of other sedatives and analgesics. The main goal in the future should be to have a clear curriculum on the role of the 'sedationalist' outside the operating room.

Gastrointestinal delivery of propofol from fospropofol: its bioavailability and activity in rodents and human volunteers.

BACKGROUND: Propofol is a safe and widely used intravenous anesthetic agent, for which additional clinical uses including treatment of migraine, nausea, pain and anxiety have been proposed (Vasileiou et al. Eur J Pharmacol 605:1-8, 2009). However, propofol suffers from several disadvantages as a therapeutic outside anesthesia including its limited aqueous solubility and negligible oral bioavailability. The purpose of the studies described here was to evaluate, in both animals and human volunteers, whether fospropofol (a water soluble phosphate ester prodrug of propofol) would provide higher propofol bioavailability through non-intravenous routes. METHODS: Fospropofol was administered via intravenous, oral and intraduodenal routes to rats. Pharmacokinetic and pharmacodynamic parameters were then evaluated. Based on the promising animal data we subsequently conducted an oral and intraduodenal pharmacokinetic/pharmacodynamic study in human volunteers. RESULTS: In rats, bioavailability of propofol from fospropofol delivered orally was found to be appreciable, in the order of around 20-70%, depending on dose. Availability was especially marked following fospropofol administration via the intraduodenal route, where bioavailability approximated 100%. Fospropofol itself was not appreciably bioavailable when administered by any route except for intravenous. Pharmacologic effect following oral fospropofol was confirmed by observation of sedation and alleviation of thermal hyperalgesia in the rat chronic constrictive injury model of neuropathic pain. The human data also showed systemic availability of propofol from fospropofol administration via oral routes, a hereto novel finding. Assessment of sedation in human volunteers was correlated with pharmacokinetic measurements. CONCLUSIONS: These data suggest potential utility of oral administration of fospropofol for various therapeutic indications previously considered for propofol.

[The sedative-hypnotic effects and safety of oral administrated propofol prodrugs hx0969w and fospropofol disodiun in comparison with propofol emulsion in rats].

OBJECTIVE: To estimate the median effective dose (EDs0) of oral administrated HX0969w, fospropofol disodium and propofol emulsion in rats, and to compare the sedative-hypnotic effects and safety of the three drugs. METHODS: The ED50 of the three drugs were determined using sequential method. Thirty healthy adult Sprague-Dawley rats were divided into three groups randomly, being orally administered with HX0969w (n=10), fospropofol disodium (n=10) and propofol emulsion (n=10), respectively. The neurobehavioral performance of the rats was observed. The time of loss of forepaw righting reflex (LRR) and the time of recovery of forepaw righting reflex (RRR) were recorded. RESULTS: The ED50 of oral HX0969w, fospropofol disodium and propofol emulsion were 96.5 mg/kg, 130.0 mg/kg and 113.8 mg/kg, respectively. HX0969w, fospropofol disodium and propofol emulsion had a mean LRR of (10.0 +/- 2.9) min,(7.5 +/- 2.8) min and (16.0 +/- 5.9) min; respectively; and a mean RRR of (66.9 +/- 21.5) min, (131.9 +/- 32.7) min and (198.9 +/- 110.0) min, respectively. CONCLUSION: HX0969w, fospropofol disodium and propofol emulsion can produce sedative-hypnotic effects and they are safe when administered by oral route. The two propofol prodrugs HX0969w and fospropofol disodium have shorter LRR than propofol emulsion. HX0969w also has a shorter RRR than fospropofol disodium and propofol emulsion.

[Sedation for fiberoptic bronchoscopy: review of the literature]. / Fiberoptik bronkoskopide sedasyon: Literatürün gözden geçirilmesi.

Fiberoptic bronchoscopy (FOB) is a procedure which has an important role in the diagnosis and treatment of lung diseases and is widely used in clinical practice. It is an invasive procedure and can cause cough, shortness of breath, nose and throat irritation. Stress during bronchoscopy can cause release of catecholamines, which may lead to tachycardia, vasoconstriction and possible myocardial ischemia in patients with impaired cardiopulmonary function. Current guidelines for bronchoscopy recommend offering sedation to patients, with the aim of improving patient comfort and reducing complications. For this purpose, the most frequently used sedatives are benzodiazepines, opioids, propofol and fospropofol which are either administered alone or in combination. In this review, we aimed to evaluate various drugs used for sedation during bronchoscopy.