-
Anesthesiology Apr 2022Opioids may produce life-threatening respiratory depression and death from their actions at the opioid receptors within the brainstem respiratory neuronal network. Since...
Opioids may produce life-threatening respiratory depression and death from their actions at the opioid receptors within the brainstem respiratory neuronal network. Since there is an increasing number of conditions where the administration of the opioid receptor antagonist naloxone is inadequate or undesired, there is an increased interest in the development of novel reversal and prevention strategies aimed at providing efficacy close to that of the opioid receptor antagonist naloxone but with fewer of its drawbacks such as its short duration of action and lesser ability to reverse high-affinity opioids, such as carfentanil, or drug combinations. To give an overview of this highly relevant topic, the authors systematically discuss predominantly experimental pharmacotherapies, published in the last 5 yr, aimed at reversal of opioid-induced respiratory depression as alternatives to naloxone. The respiratory stimulants are discussed based on their characteristics and mechanism of action: nonopioid controlled substances (e.g., amphetamine, cannabinoids, ketamine), hormones (thyrotropin releasing hormone, oxytocin), nicotinic acetylcholine receptor agonists, ampakines, serotonin receptor agonists, antioxidants, miscellaneous peptides, potassium channel blockers acting at the carotid bodies (doxapram, ENA001), sequestration techniques (scrubber molecules, immunopharmacotherapy), and opioids (partial agonists/antagonists). The authors argue that none of these often still experimental therapies are sufficiently tested with respect to efficacy and safety, and many of the agents presented have a lesser efficacy at deeper levels of respiratory depression, i.e., inability to overcome apnea, or have ample side effects. The authors suggest development of reversal strategies that combine respiratory stimulants with naloxone. Furthermore, they encourage collaborations between research groups to expedite development of viable reversal strategies of potent synthetic opioid-induced respiratory depression.
Topics: Analgesics, Opioid; Humans; Naloxone; Narcotic Antagonists; Respiratory Insufficiency; Respiratory System Agents
PubMed: 34958670
DOI: 10.1097/ALN.0000000000004096 -
BMJ Open Sep 2021Apnoea affects 85% of premature infants under 34 weeks of age and would be an important risk factor for subsequent neuropsychological disorders. Currently, premature...
Protocol of controlled odorant stimulation for reducing apnoeic episodes in premature newborns: a randomised open-label Latin-square study with independent evaluation of the main endpoint (PREMODEUR).
INTRODUCTION
Apnoea affects 85% of premature infants under 34 weeks of age and would be an important risk factor for subsequent neuropsychological disorders. Currently, premature children with life-threatening apnoeas receive stimulants such as methylxanthines (mainly, caffeine) or doxapram (an analeptic unlicensed in children under 15). However, these products have undesirable effects (hyperarousal, irritability, sleep disorders, tachycardia) and are not always effective because apnoea does persist in some premature newborns. Previous studies have indicated that odorant stimulation, a non-invasive intervention, may stimulate the respiratory rhythm. The objective of the present protocol is to reduce the occurrence of apnoeic episodes in premature newborns by controlled odorant stimulation added to current pharmacological treatments.
METHODS AND ANALYSIS
The project is a randomised open-label Latin-square trial with independent evaluation of the main endpoint. It will include 60 preterm neonates from two university hospital neonatal intensive care units over 2 years (2021-2023). Each newborn will receive no (S0), sham (S1) or real olfactory stimulation (S2) in random order. During S2, three distinct odorants (mint, grapefruit and vanilla) will be delivered successively, in puffs, over 24 hours. Mint and grapefruit odours stimulate the main and the trigeminal olfactory pathways, whereas vanilla odour stimulates only the main olfactory pathway. A statistical analysis will compare the incidence of apnoeic episodes during S1 versus S2 using a mixed effects Poisson model.
ETHICS AND DISSEMINATION
Ethical approval was obtained from the Comité de Protection des Personnes Île-de-France XI (# 2017-AO13-50-53). The results will be disseminated through various scientific meetings, specialised peer-reviewed journals and, whenever possible, posted on appropriate public websites.
TRIAL REGISTRATION NUMBER
NCT02851979; Pre-results.
Topics: Apnea; Child; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intensive Care Units, Neonatal; Odorants; Randomized Controlled Trials as Topic
PubMed: 34518252
DOI: 10.1136/bmjopen-2020-047141 -
Frontiers in Pharmacology 2021Atrial fibrillation (AF) is the most common sustained arrhythmia with a prevalence of up to 4% and an upwards trend due to demographic changes. It is associated with an... (Review)
Review
Atrial fibrillation (AF) is the most common sustained arrhythmia with a prevalence of up to 4% and an upwards trend due to demographic changes. It is associated with an increase in mortality and stroke incidences. While stroke risk can be significantly reduced through anticoagulant therapy, adequate treatment of other AF related symptoms remains an unmet medical need in many cases. Two main treatment strategies are available: rate control that modulates ventricular heart rate and prevents tachymyopathy as well as rhythm control that aims to restore and sustain sinus rhythm. Rate control can be achieved through drugs or ablation of the atrioventricular node, rendering the patient pacemaker-dependent. For rhythm control electrical cardioversion and pharmacological cardioversion can be used. While electrical cardioversion requires fasting and sedation of the patient, antiarrhythmic drugs have other limitations. Most antiarrhythmic drugs carry a risk for pro-arrhythmic effects and are contraindicated in patients with structural heart diseases. Furthermore, catheter ablation of pulmonary veins can be performed with its risk of intraprocedural complications and varying success. In recent years TASK-1 has been introduced as a new target for AF therapy. Upregulation of TASK-1 in AF patients contributes to prolongation of the action potential duration. In a porcine model of AF, TASK-1 inhibition by gene therapy or pharmacological compounds induced cardioversion to sinus rhythm. The DOxapram Conversion TO Sinus rhythm (DOCTOS)-Trial will reveal whether doxapram, a potent TASK-1 inhibitor, can be used for acute cardioversion of persistent and paroxysmal AF in patients, potentially leading to a new treatment option for AF.
PubMed: 33897427
DOI: 10.3389/fphar.2021.638445 -
Frontiers in Veterinary Science 2021Sepsis is a frequent life-threatening condition in young calves, requiring rapid broad spectrum and bactericidal therapy to maximize survival chances. Few studies have...
Sepsis is a frequent life-threatening condition in young calves, requiring rapid broad spectrum and bactericidal therapy to maximize survival chances. Few studies have identified and characterized bacteria involved in sepsis in calves. This report demonstrates the involvement of a multidrug resistant , an emerging pathogen in human medicine, in a calf with suspected sepsis. was identified by MALDI-TOF MS from blood cultures of a critically ill calf. Susceptibility testing showed phenotypic resistance against ampicillin, gentamicin, potentiated sulphonamides, streptomycin, tetracyclines and intermediate susceptibility for enrofloxacin. Whole genome sequencing confirmed identification as and the multidrug resistant character of the isolate. Antimicrobial resistance genes acting against aminoglycosides, beta-lactam antibiotics, fosfomycin, quinolones, sulphonamides, trimethoprim and tetracyclines were found. The calf recovered after empirical parenteral therapy with enrofloxacin and sodium penicillin for seven days. Ancillary therapy consisted of fluid therapy, ketoprofen and doxapram hydrochloride. To the authors' knowledge, this is the first report characterizing a multidrug resistant isolate from blood culture in cattle. It is currently unknown whether animals and farms may act as reservoirs for multidrug resistant strains.
PubMed: 33842574
DOI: 10.3389/fvets.2021.631716 -
Neonatology 2021Apnea of prematurity can persist despite caffeine therapy in preterm infants. Doxapram may additionally support breathing. Although multiple small studies have reported...
BACKGROUND
Apnea of prematurity can persist despite caffeine therapy in preterm infants. Doxapram may additionally support breathing. Although multiple small studies have reported the efficacy of doxapram, the structural co-treatment with caffeine impedes to ascribe the efficacy to doxapram itself or to a pharmacokinetic (PK) interaction where doxapram increases the exposure to caffeine. We examined whether there is a PK drug-drug interaction between doxapram and caffeine by developing a PK model for caffeine including infants with and without doxapram treatment.
METHODS
In preterm neonates receiving caffeine, we determined caffeine plasma concentrations before, during, and directly after doxapram co-treatment and used these to develop a population PK model in NONMEM 7.3. Patient characteristics and concomitant doxapram administration were tested as covariates.
RESULTS
166 plasma samples were collected from 39 preterm neonates receiving caffeine (median gestational age 25.6 [range 24.0-28.0] weeks) of which 65 samples were taken during co-treatment with doxapram (39%, from 32/39 infants). Clearance of caffeine was 9.99 mL/h for a typical preterm neonate with a birth weight of 0.8 kg and 23 days postnatal age and increased with birth weight and postnatal age, resulting in a 4-fold increase in clearance during the first month of life. No PK interaction between caffeine and doxapram was identified.
DISCUSSION
Caffeine clearance is not affected by concomitant doxapram therapy but shows a rapid maturation with postnatal age. As current guidelines do not adjust the caffeine dose with postnatal age, decreased exposure to caffeine might partly explain the need for doxapram therapy after the first week of life.
Topics: Apnea; Caffeine; Doxapram; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases
PubMed: 33626528
DOI: 10.1159/000513413 -
American Journal of Veterinary Research Jan 2021To determine the effects of dexmedetomidine, doxapram, and dexmedetomidine plus doxapram on ventilation ([Formula: see text]e), breath frequency, and tidal volume (Vt)...
OBJECTIVE
To determine the effects of dexmedetomidine, doxapram, and dexmedetomidine plus doxapram on ventilation ([Formula: see text]e), breath frequency, and tidal volume (Vt) in ball pythons () and of doxapram on the thermal antinociceptive efficacy of dexmedetomidine.
ANIMALS
14 ball pythons.
PROCEDURES
Respiratory effects of dexmedetomidine and doxapram were assessed with whole-body, closed-chamber plethysmography, which allowed for estimates of [Formula: see text]e and Vt. In the first experiment of this study with a complete crossover design, snakes were injected, SC, with saline (0.9% NaCl) solution, dexmedetomidine (0.1 mg/kg), doxapram (10 mg/kg), or dexmedetomidine and doxapram, and breath frequency, [Formula: see text]e, and Vt were measured before and every 30 minutes thereafter, through 240 minutes. In the second experiment, antinociceptive efficacy of saline solution, dexmedetomidine, and dexmedetomidine plus doxapram was assessed by measuring thermal withdrawal latencies before and 60 minutes after SC injection.
RESULTS
Dexmedetomidine significantly decreased breath frequency and increased Vt but did not affect [Formula: see text]e at all time points, compared with baseline. Doxapram significantly increased [Formula: see text]e, breath frequency, and Vt at 60 minutes after injection, compared with saline solution. The combination of dexmedetomidine and doxapram, compared with dexmedetomidine alone, significantly increased [Formula: see text]e at 30 and 60 minutes after injection and did not affect breath frequency and Vt at all time points. Thermal withdrawal latencies significantly increased when snakes received dexmedetomidine or dexmedetomidine plus doxapram, versus saline solution.
CONCLUSIONS AND CLINICAL RELEVANCE
Concurrent administration of doxapram may mitigate the dexmedetomidine-induced reduction of breathing frequency without disrupting thermal antinociceptive efficacy in ball pythons.
Topics: Analgesics; Animals; Boidae; Dexmedetomidine; Doxapram; Respiration
PubMed: 33369496
DOI: 10.2460/ajvr.82.1.11 -
Veterinary Medicine and Science Mar 2021The present prospective randomized experimental study was designed to determine the effects of doxapram on haematological, serum biochemical and antioxidant status in...
The present prospective randomized experimental study was designed to determine the effects of doxapram on haematological, serum biochemical and antioxidant status in dogs after propofol anaesthesia. Twenty-four healthy male mixed breed dogs, aged 1-2 years, weighing 20.4 ± 2.6 kg was studied. Each dog was anaesthetized twice, with at least one week for washout. Animals were sedated with acepromazine (0.1 mg/kg) intramuscularly. Forty minutes later, anaesthesia was induced using intravenous (IV) propofol (4 mg/kg) titration and maintained for 30 min by propofol (0.2 mg kg min ). After propofol was discontinued, doxapram (2 mg/kg) hydrochloride was administrated IV in PD treatment while an equal volume of saline was administrated in PS treatment. Blood parameters were analysed in four times: immediately before sedation (T1), after treatment (T2), after complete recovery (T3) and 24 hr later (T4). Haematological assessments revealed no significant difference between treatments except in haematocrit which was significantly reduced at T4 (24 hr later) in PD. A decreasing trend of all haematological variables was observed after doxapram administration until recovery, except monocyte, mean corpuscular haemoglobin, red blood cell distribution width and platelet count. Serum urea, creatinine, glucose, cholesterol, direct bilirubin concentration and alanine aminotransferase activity were not changed following doxapram administration compared to the PS treatment. After doxapram administration, Creatinine (T3), Albumin (T2) and Protein (T2 & T3) decreased while Glucose (T2 & T3) and BT (T3) increased. Antioxidant parameters measured showed no difference between treatments or time. Doxapram (2 mg/kg) IV did not induce any major negative effects on haematological, serum biochemical variables and oxidant/antioxidant status in dogs after propofol anaesthesia.
Topics: Anesthetics; Animals; Antioxidants; Blood Chemical Analysis; Central Nervous System Stimulants; Dogs; Doxapram; Erythrocytes; Hematologic Tests; Oxidants; Propofol
PubMed: 33210449
DOI: 10.1002/vms3.398 -
Neonatology 2020Evaluation of pharmacotherapy during intensive care treatment is commonly based on subjective, intermittent interpretations of physiological parameters. Real-time... (Observational Study)
Observational Study
INTRODUCTION
Evaluation of pharmacotherapy during intensive care treatment is commonly based on subjective, intermittent interpretations of physiological parameters. Real-time visualization and analysis may improve drug effect evaluation. We aimed to evaluate the effects of the respiratory stimulant doxapram objectively in preterm infants using continuous physiological parameters.
METHODS
In this longitudinal observational study, preterm infants who received doxapram therapy were eligible for inclusion. Physiological data (1 Hz) were used to assess respiration and to evaluate therapy effects. The oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) ratio and the area under the 89% SpO2 curve (duration × saturation depth below target) were calculated as measures of hypoxemia. Regression analyses were performed in 1-h timeframes to discriminate therapy failure (intubation or death) from success (no intubation).
RESULTS
Monitor data of 61 patients with a median postmenstrual age (PMA) at doxapram initiation of 28.7 (IQR 27.6-30.0) weeks were available. The success rate of doxapram therapy was 56%. Doxapram pharmacodynamics were reflected in an increased SpO2 and SpO2/FiO2 ratio as well as a decrease in episodes with saturations below target (SpO2 <89%). The SpO2/FiO2 ratio, corrected for PMA and mechanical ventilation before therapy start, discriminated best between therapy failure and success (highest AUC ROC of 0.83).
CONCLUSION
The use of continuous physiological monitor data enables objective and detailed interpretation of doxapram in preterm infants. The SpO2/FiO2 ratio is the best predictive parameter for therapy failure or success. Further implementation of real-time data analysis and treatment algorithms would provide new opportunities to treat newborns.
Topics: Doxapram; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Oxygen; Respiratory System Agents
PubMed: 32841955
DOI: 10.1159/000509269 -
Sleep Jan 2021Obstructive sleep apnea (OSA) occurs exclusively during sleep due to reduced tongue motor activity. Withdrawal of excitatory inputs to the hypoglossal motor nucleus...
Modulation of TASK-1/3 channels at the hypoglossal motoneuron pool and effects on tongue motor output and responses to excitatory inputs in vivo: implications for strategies for obstructive sleep apnea pharmacotherapy.
Obstructive sleep apnea (OSA) occurs exclusively during sleep due to reduced tongue motor activity. Withdrawal of excitatory inputs to the hypoglossal motor nucleus (HMN) from wake to sleep contributes to this reduced activity. Several awake-active neurotransmitters with inputs to the HMN (e.g. serotonin [5-HT]) inhibit K+ leak mediated by TASK-1/3 channels on hypoglossal motoneurons, leading to increased neuronal activity in vitro. We hypothesize that TASK channel inhibition at the HMN will increase tongue muscle activity in vivo and modulate responses to 5-HT. We first microperfused the HMN of anesthetized rats with TASK channel inhibitors: doxapram (75 μM, n = 9), A1899 (25 μM, n = 9), ML365 (25 μM, n = 9), acidified artificial cerebrospinal fluid (ACSF, pH = 6.25, n = 9); and a TASK channel activator terbinafine (50 μM, n = 9); all with and without co-applied 5-HT (10 mM). 5-HT alone at the HMN increased tongue motor activity (202.8% ± 45.9%, p < 0.001). However, neither the TASK channel inhibitors, nor activator, at the HMN changed baseline tongue activity (p > 0.716) or responses to 5-HT (p > 0.127). Tonic tongue motor responses to 5-HT at the HMN were also not different (p > 0.05) between ChAT-Cre:TASKf/f mice (n = 8) lacking TASK-1/3 channels on cholinergic neurons versus controls (n = 10). In freely behaving rats (n = 9), microperfusion of A1899 into the HMN increased within-breath phasic tongue motor activity in wakefulness only (p = 0.005) but not sleep, with no effects on tonic activity across all sleep-wake states. Together, the findings suggest robust maintenance of tongue motor activity despite various strategies for TASK channel manipulation targeting the HMN in vivo, and thus currently do not support this target and direction for potential OSA pharmacotherapy.
Topics: Animals; Hypoglossal Nerve; Mice; Motor Neurons; Rats; Rats, Wistar; Sleep Apnea, Obstructive; Tongue
PubMed: 32745213
DOI: 10.1093/sleep/zsaa144 -
Paediatric Drugs Aug 2020Caffeine is a common treatment for neonatal intensive care management of the developmental complication of apnea of prematurity in preterm infants. There are several...
BACKGROUND
Caffeine is a common treatment for neonatal intensive care management of the developmental complication of apnea of prematurity in preterm infants. There are several systematic reviews (SRs) on the performance of caffeine in the treatment of apnea. The evidence provided by those, however, is depressed by an information overload due to high heterogeneity in the characteristics as well as the quality of these SRs.
OBJECTIVE
The aim was to provide a systematic overview of SRs on the use of caffeine for the management of neonatal apnea. Such overviews are a recent method used to assess and filter top evidence among SRs, enabling enhanced access to targeted information of interest.
METHODS
A comprehensive literature search was conducted via EMBASE, Cochrane Database of Systematic Reviews (CDSR), and PubMed since inception to January 2020. Two reviewers independently conducted study selection and data extraction, and assessed the quality of methods and the risk of bias in included SRs based on A Measurement Tool to Assess Systematic Reviews (AMSTAR-2) and Risk of Bias in Systematic Reviews (ROBIS) tools. Extracted data related to study type, characteristics, patients, intervention, comparator, regimen, and outcome measures.
RESULTS
Seven SRs with meta-analyses (SRMAs) were included in the current overview, involving a total of 63,315 neonates. SRMAs included randomized clinical and observational studies, with various types of patients, comparators, and outcomes. The quality of SRMAs ranged from critically low (n = 1), low (n = 1), moderate (n = 2), to high (n = 3), and the risk of bias was unclear (n = 2), low (n = 4), and high (n = 1). The effectiveness of caffeine with regard to treatment success and the rate of apnea was not significantly different from that of theophylline or doxapram in two SRMAs. Against control, in one SRMA, while caffeine reduced the rate of failure as well as the need for pressure ventilation, it did not significantly reduce mortality. This comparative effectiveness of caffeine was based on high-quality SRMAs with a low risk of bias. The effectiveness against apnea seems to be enhanced via the administration of early (0-2 days) or high doses of caffeine in one and three SRMAs, respectively. This, nevertheless, was based on lower-quality SRMAs with a higher risk of bias. Safety outcomes were mostly based on comparative SRMAs of different drug regimens, whereby, less tachycardia and lower risk for complications were reported with lower and earlier caffeine administrations, respectively. The evidence behind this, however, was limited in quantity and quality.
CONCLUSION
While limited in quantity, there is evidence of non-inferior effectiveness of caffeine against other methylxanthines or doxapram for the management of apnea in neonates. Owing to the limited quality, however, limited evidence exists in support of an optimal administration regimen for caffeine. Further controlled studies are, therefore, needed to confirm the comparative usefulness of caffeine as well as to assess its different potential regimens, including in relation to safety.
Topics: Apnea; Caffeine; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intensive Care Units, Neonatal; Randomized Controlled Trials as Topic; Theophylline; Treatment Outcome
PubMed: 32488731
DOI: 10.1007/s40272-020-00404-4