Number Of Coughs Research Articles

Effect of Dezocine on Hemodynamic Indexes of Postoperative Patients With Traumatic Brain Injury (TBI)---A Pilot Study.

Background: Due to pain and other stimuli, patients with traumatic brain injury (TBI) after surgery show excited Sympathetic Nervous system, increased intracranial pressure, brain tissue swelling, intracranial hemorrhage, or reduced cerebral perfusion pressure, seriously threatening the life and prognosis of patients. The effect of dezocine on postoperative analgesia after TBI remains largely undetermined. Objective: In the present study, we aimed to investigate the efficacy and safety of dezocine in postoperative sedative and analgesic therapy for a craniocerebral injury. Methods: The patients were randomly divided into two groups (n = 40) as follows: dezocine group (Group A) and control group (Group B). Electrocardiography (ECG), heart rate (HR), blood pressure, and oxygen saturation (SpO2) were routinely monitored after postoperative return to the ward. Both groups were initially injected with 5 mg·kg−1·h−1 propofol to maintain sedation, and the dose was adjusted according to the patient’s condition. Vital signs of patients were recorded at T1 (the base value when arriving at the ward), T2 (before the sedative agent was used) and T3 (use of dezocine or 0.9% saline solution for 8 h), T4 (use for 1 day), T5 (use for 3 days), T6 (termination of dezocine or 0.9% saline solution for 1 day), and T7 (termination for 3 days), and mean arterial pressure (MAP) and HR values were also recorded. The total amount of propofol, total fluid inflow, blood loss, and urine output were recorded within 24 h. The number of coughs of each patient was recorded within 1 day after entry, and the incidence of adverse events, such as insufficient oxygenation (SaO2 reduced by about 5% from the base value), hypotension, bradycardia, laryngospasm, bronchospasm, and so on, was assessed. Results: Compared with the control group (group B), the hemodynamics of the dezocine group (group A) was more stable, there were significant differences in MAP and HR (p < 0.05), and the stress response was milder. The total amount of propofol, total fluid inflow, blood loss, and urine volume of the dezocine group were significantly improved compared with the control group (p < 0.05). Moreover, the incidence of adverse events, such as cough, in the dezocine group was significantly reduced compared with the control group (p < 0.05). Conclusions: Dezocine, as a drug with a strong analgesic effect and obvious sedative effect, was suitable for craniocervical surgery, and it could significantly improve the stability of airway and hemodynamics in TBI patients during anesthesia recovery.

Modeling and simulation of vagal afferent input of the cough reflex

We employed computational modeling to investigate previously conducted experiments of the effect of vagal afferent modulation on the cough reflex in an anesthetized cat animal model. Specifically, we simulated unilateral cooling of the vagus nerve and analyzed characteristics of coughs produced by a computational model of brainstem cough/respiratory neuronal network. Unilateral vagal cooling was simulated by a reduction of cough afferent input (corresponding to unilateral vagal cooling) to the cough network. All these attempts resulted in only mild decreases in investigated cough characteristics such as cough number, amplitudes of inspiratory and expiratory cough efforts in comparison with experimental data. Multifactorial alterations of model characteristics during cough simulations were required to approximate cough motor patterns that were observed during unilateral vagal cooling in vivo. The results support the plausibility of a more complex NTS processing system for cough afferent information than has been proposed.

Cough detection using a non-contact microphone: A nocturnal cough study.

An automatic non-contact cough detector designed especially for night audio recordings that can distinguish coughs from snores and other sounds is presented. Two different classifiers were implemented and tested: a Gaussian Mixture Model (GMM) and a Deep Neural Network (DNN). The detected coughs were analyzed and compared in different sleep stages and in terms of severity of Obstructive Sleep Apnea (OSA), along with age, Body Mass Index (BMI), and gender. The database was composed of nocturnal audio signals from 89 subjects recorded during a polysomnography study. The DNN-based system outperformed the GMM-based system, at 99.8% accuracy, with a sensitivity and specificity of 86.1% and 99.9%, respectively (Positive Predictive Value (PPV) of 78.4%). Cough events were significantly more frequent during wakefulness than in the sleep stages (p < 0.0001) and were significantly less frequent during deep sleep than in other sleep stages (p < 0.0001). A positive correlation was found between BMI and the number of nocturnal coughs (R = 0.232, p < 0.05), and between the number of nocturnal coughs and OSA severity in men (R = 0.278, p < 0.05). This non-contact cough detection system may thus be implemented to track the progression of respiratory illnesses and test reactions to different medications even at night when a contact sensor is uncomfortable or infeasible.

Estimating Tuberculosis Transmission Risks in a Primary Care Clinic in South Africa: Modeling of Environmental and Clinical Data.

Congregate settings, such as healthcare clinics, may play an essential role in Mycobacterium tuberculosis (Mtb) transmission. Using patient and environmental data, we studied transmission at a primary care clinic in South Africa. We collected patient movements, cough frequency, and clinical data, and measured indoor carbon dioxide (CO2) levels, relative humidity, and Mtb genomes in the air. We used negative binomial regression model to investigate associations. We analyzed 978 unique patients who contributed 14795 data points. The median patient age was 33 (interquartile range [IQR], 26-41) years, and 757 (77.4%) were female. Overall, median CO2 levels were 564 (IQR 495-646) parts per million and were highest in the morning. Median number of coughs per day was 466 (IQR, 368-503), and overall median Mtb DNA copies/μL/day was 4.2 (IQR, 1.2-9.5). We found an increased presence of Mtb DNA in the air of 32% (95% credible interval, 7%-63%) per 100 additional young adults (aged 15-29 years) and 1% (0-2%) more Mtb DNA per 10% increase of relative humidity. Estimated cumulative transmission risks for patients attending the clinic monthly for at least 1 hour range between 9% and 29%. We identified young adults and relative humidity as potentially important factors for transmission risks in healthcare clinics. Our approach should be used to detect transmission and evaluate infection control interventions.

The role of neuronal excitation and inhibition in the pre-Bötzinger complex on the cough reflex in the cat.

Brainstem respiratory neuronal network significantly contributes to cough motor pattern generation. Neuronal populations in the pre-Bötzinger complex (PreBötC) represent a substantial component for respiratory rhythmogenesis. We studied the role of PreBötC neuronal excitation and inhibition on mechanically induced tracheobronchial cough in 15 spontaneously breathing, pentobarbital anesthetized adult cats (35 mg/kg, iv initially). Neuronal excitation by unilateral microinjection of glutamate analog d,l-homocysteic acid resulted in mild reduction of cough abdominal electromyogram (EMG) amplitudes and very limited temporal changes of cough compared with effects on breathing (very high respiratory rate, high amplitude inspiratory bursts with a short inspiratory phase, and tonic inspiratory motor component). Mean arterial blood pressure temporarily decreased. Blocking glutamate-related neuronal excitation by bilateral microinjections of nonspecific glutamate receptor antagonist kynurenic acid reduced cough inspiratory and expiratory EMG amplitude and shortened most cough temporal characteristics similarly to breathing temporal characteristics. Respiratory rate decreased and blood pressure temporarily increased. Limiting active neuronal inhibition by unilateral and bilateral microinjections of GABAA receptor antagonist gabazine resulted in lower cough number, reduced expiratory cough efforts, and prolongation of cough temporal features and breathing phases (with lower respiratory rate). The PreBötC is important for cough motor pattern generation. Excitatory glutamatergic neurotransmission in the PreBötC is involved in control of cough intensity and patterning. GABAA receptor-related inhibition in the PreBötC strongly affects breathing and coughing phase durations in the same manner, as well as cough expiratory efforts. In conclusion, differences in effects on cough and breathing are consistent with separate control of these behaviors.NEW & NOTEWORTHY This study is the first to explore the role of the inspiratory rhythm and pattern generator, the pre-Bötzinger complex (PreBötC), in cough motor pattern formation. In the PreBötC, excitatory glutamatergic neurotransmission affects cough intensity and patterning but not rhythm, and GABAA receptor-related inhibition affects coughing and breathing phase durations similarly to each other. Our data show that the PreBötC is important for cough motor pattern generation, but cough rhythmogenesis appears to be controlled elsewhere.

Identification of COVID-19 from Cough Sounds Using Non-Linear Analysis and Machine Learning

Automatic diagnosis of COVID-19 has an active role in reducing the spread of the disease by minimizing interaction with people. Machine learning models using various signals and images form the basis of automatic diagnosis. This study presents the machine learning based models for detecting COVID-19 infection using ‘Virufy’ dataset containing cough sound signals labeled as COVID-19 and Non-COVID-19. Since the number of COVID positive coughs in the set is less than those of COVID negative, firstly, data balancing was performed with the ADASYN oversampling technique in the study. Then, features were extracted by non-linear analysis of cough sounds using Multifractal Detrended Fluctuation Analysis (MDFA), Lempel–Ziv Complexity (LZC) and entropy measures. Later, the most effective features were selected by ReliefF method. Finally, five machine learning algorithms, namely Support Vector Machine with Radial Basis Function (SVM-RBF), Random Forest (RF), Adaboost, Artificial Neural Network (ANN), k Nearest Neighbor (kNN) were used to identify cough sounds as COVID-19 or Non-COVID19. As a result of the study, the cough sounds of COVID-19 patients and Non-COVID19 subjects were identified with 95.8% classification accuracy thanks to the RBF kernel function of SVM and the selected effective features. With this classifier, 93.1% sensitivity, 98.6% specificity, 98.6% precision, 0.92 kappa statistical values and 93.2% area under the ROC curve were obtained.

Chemical characteristics and significant antitussive effect of the Erigeron canadensis polyphenolic polysaccharide-protein complex

Ethnopharmacological relevanceErigeron canadensis has been used in traditional medicine to treat a variety of respiratory diseases, including acute upper and lower respiratory tract infections and cough-related asthma. There is as yet no relevant experimental or clinical study in the scientific literature evaluating the efficacy of plants in these disorders. Aim of the studyTo investigate the active ingredients in Erigeron canadensis, a complex isolated from flowering parts of a plant was tested for airway defense reflexes, in particular for cough reflexes and airway reactivity. Both were experimentally induced by a chemical irritant that simulated the inflammatory conditions of their formation. Material and methodsThe polyphenolic polysaccharide-protein (PPP) complex was isolated from the flowering parts of Erigeron canadensis by hot alkaline extraction and a multi-stage purification process. The antitussive activity was confirmed as a decrease in the number of citric acid-induced coughs and the bronchodilator effect was verified as a decrease in specific airway resistance (sRaw) in conscious guinea pigs. ResultsThe dark brown Erigeron complex with a molecular weight of 38,000 g/mol contained phenolics (13.2% wt%), proteins (16.3% wt%), and uronic acids (6.3% wt%). The neutral carbohydrate part of Erigeron consisted mainly of xylose (12.1 wt%), glucose (13.3 wt%), arabinose (24.1 wt%), and galactose (41.0 wt%) residues. Arabinogalactan and 4-OMe-glucuronoxylan have been found to be the major polysaccharides in the Erigeron complex. Using a method of chemically-induced cough reflex and guinea pigs test system the Erigeron complex exhibited statistically significant, the dose-dependent antitussive activity, which was similar to that of the centrally-acting opioid agonist codeine. ConclusionPharmacological tests have revealed a new pharmacodynamic effect of the Erigeron complex, namely an antitussive effect. Its activity was most pronounced in comparison with all previously tested compounds from other medicinal plants and approached the effect of codeine, the most potent antitussive used in clinical practice. The results provide the scientific basis for the application of this herb in traditional medicine.

Randomised trial of the P2X3 receptor antagonist sivopixant for refractory chronic cough.

BackgroundThe purinoceptor subtype P2X3 has been shown to have significant involvement in the cough reflex; the heterotrimer version of the purinoceptor (P2X2/3) has been implicated in taste disturbance. The most advanced clinical candidate antagonist gefapixant has low selectivity among P2X3 receptors and induced taste disturbance, whereas newly developed sivopixant has high selectivity towards P2X3 versus P2X2/3.MethodsIn a phase 2a, randomised, double-blind, placebo-controlled, crossover, multicentre study, adult patients with refractory or unexplained chronic cough received oral sivopixant 150 mg or placebo once daily for 2 weeks, followed by a 2–3-week washout period, and then crossed over to placebo or sivopixant for 2 weeks. Efficacy and safety of sivopixant were evaluated.ResultsOf 31 randomised patients, 15 in the sivopixant-first group and 15 in the placebo-first group completed the study. After 2 weeks of treatment, the placebo-adjusted ratios of the average hourly number of coughs to baseline during daytime (primary end-point) and over 24 h (secondary end-point) were −31.6% (p=0.0546) and −30.9% (p=0.0386), respectively. Sivopixant also improved health-related quality of life. Treatment-related adverse events occurred in 12.9% and 3.2% of patients during sivopixant and placebo administration, respectively. Mild taste disturbance occurred in two patients (6.5%) during sivopixant administration.ConclusionsSivopixant reduced objective cough frequency and improved health-related quality of life, with a low incidence of taste disturbance, among patients with refractory or unexplained chronic cough.

Effect of centrally and peripherally acting GABAB agonism on the healthy human cough reflex

BackgroundCurrently there are no effective licensed anti-tussive therapies. Understanding how the neuronal mechanisms mediating the cough reflex in animal models translate to humans is important for the development of effective therapies. Pre-clinical studies suggest that the activation of GABAB receptors in both the peripheral and central nervous systems inhibit cough. ObjectiveTo compare the effect of central and peripherally acting GABAB agonists (lesogaberan and baclofen) on the cough reflex in healthy volunteers. MethodsWe performed a single center, double-blind, double-dummy, three-way crossover trial in healthy controls comparing single doses of lesogaberan (120 mg MR), with baclofen (40 mg) and placebos. Cough responses to inhaled capsaicin were assessed at screening and 2h post-dose on each study day. The primary endpoint was the maximum number of coughs evoked at any concentration of capsaicin (Emax) and the secondary endpoint was the concentration evoking 50% of the maximal response (ED50). ResultsFifteen participants enrolled onto the study (median age 29 (IQR 25–44) years; 7 females, mean BMI 24.6(±3.0). Lesogaberan treatment produced a small, statistically significant increase in Emax compared with placebo [mean 13.4coughs (95%CI 10.1–17.9) vs. 11.8coughs (8.8–15.9), p = 0.04], but had no effect on ED50 [geometric mean 47.4 μM (95%CI 24.4–91.7) vs 37.6 μM (95%CI 19.2–73.5), p = 0.37]. In contrast, baclofen had no significant effect on Emax (11.1, 95%CI 8.1–15.4) (p = 0.23), but significantly increased ED50 compared with placebo (geometric mean 75.2 μM (95%CI 37.2–151.8), p = 0.002). ConclusionThis data suggests the anti-tussive actions of GABAB agonists, in healthy volunteers, occur in the central rather than the peripheral nervous system.

Suhuang antitussive capsule ameliorates post-infectious cough in mice through AhR-Nrf2 pathway

Ethnopharmacological relevanceSuhuang antitussive capsule (SH capsule), a typical traditional Chinese medicines (TCMs) compound, is widely used for the treatment of post-infectious cough (PIC) in the clinic. Our previous studies have demonstrated that SH capsule possesses significant ameliorative effects on cough variant asthma (CVA), sputum obstruction and airway remodeling. Aim of the studyThis study is designed to investigate the ameliorative effects and potential mechanisms of SH capsule on PIC in mice. Materials and methodsTo establish the PIC model, ICR mice were induced by lipopolysaccharide (LPS) (3 mg/kg) once, followed by cigarettes smoke (CS) exposure for 30 min per day for 30 days. Mice were intragastrically (i.g.) administrated with SH capsule at the doses of 3.5, 7, 14 g/kg each day for 2 weeks since the 24th day. The number of coughs, coughs latencies, enzyme-linked immunosorbent assay (ELISA) and histological analysis were used to investigate the effects of SH capsule on PIC mice. Quantitative-polymerase chain reaction (Q-PCR) and western blotting were conducted to evaluate the levels of mRNA and proteins associated with Aryl hydrocarbon receptor (AhR)–NF–E2-related factor 2 (Nrf2) pathway. Superoxide dismutase (SOD), glutathione (GSH) and total antioxidant capacity (T-AOC) assays were performed to evaluate the oxidative stress. A549 cells were used to investigate the ameliorative effects of SH capsule in vitro. ResultsSH capsule effectively diminished the number of coughs and extended coughs latencies in PIC mice. The airway inflammation was alleviated by decreasing the expression levels of inflammatory mediators including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Moreover, SH capsule dose-dependently activated AhR-Nrf2 pathway and induced the nuclear translocation in vitro and in vivo. Besides, SH capsule significantly increased the levels of SOD, GSH and T-AOC in mice. ConclusionOur study demonstrates that SH capsule ameliorates airway inflammation-associated PIC in mice through activating AhR-Nrf2 pathway and consequently alleviating inflammatory responses and oxidative stress.

Deep Inspiration-Provoked Cough: A Sign of Cough Reflex Arc Hypersensitivity.

Deep inspiration-provoked cough (DIPC) is a form of allotussia. Allotussia is thought to be a manifestation of cough reflex arc hypersensitivity but objective evidence about this is lacking. 36 subjects with chronic cough and 25 healthy subjects underwent mannitol and citric acid cough provocation tests. DIPC was defined as two or more coughs after deep inhalation of an empty mannitol capsule. Citric acid was administered utilizing a dosimetric nebulizer during controlled tidal breathing. Nine subjects demonstrated DIPC, 8/36 subjects with chronic cough and 1/25 healthy subjects (p = 0.048). The concentration of citric acid to provoke five or more coughs (C5) was 23.4 (63.8) mM among subjects with DIPC and 750 (2941) mM among the subjects without it (p = 0.006). The number of deep inspiration-provoked coughs correlated with the citric acid C5 (Rs -0.38, p = 0.002). In conclusion, DIPC, a form of allotussia, is associated with cough reflex arc hypersensitivity.Trial Registration Number.ClinicalTrials.gov database KUH5801136.

Preliminary investigation of the aqueous leaf extract of Chrysophyllum albidum George Don (Sapotaceae) in laboratory-induced cough

Cough is the most common symptom of respiratory diseases, however, in distressing and severe cases, opioids are effective, but their use has been challenged by side effects such as sedation, constipation; also, by some addictive liability, as well as the compromise of respiratory function. Therefore, there is a dire need for effective antitussives that will override the limitations of the opioids. Chrysophyllum albidum (Linn), family Sapotaceae, and also known as African star apple is primarily a forest tree species with its natural occurrences in diverse ecozones in Uganda, Nigeria and Niger Republic. Across Nigeria, it is known by several local names, for example, as ‘Agbalumo’ in Yoruba, and is generally regarded as a plant with diverse ethno-medicinal uses, including the treatment of cough and asthma. The present study was designed to evaluate possible antitussive activity of Chrysophyllum albidum. Cough was induced in the animals using 25 % ammonium hydroxide- and acetic acid (concentrated), after which the mice were randomized into treatment groups as follows: (Group 1, normal control), 10 mg/kg dextromethorphan (Group 2), 5.7 mg/kg codeine (Group 3), 100, 200 and 400 mg/kg, Chrysophyllum albidum (groups 4, 5 and 6). Cough induction was carried out in an enclosed dessicator for one minute and the number of coughs was, counted and recorded for five minutes. The animals were further exposed at 30, 60, 90 and 120 minutes. The same procedure was repeated for acetic acid-induced cough. Chrysophyllum albidum showed significant antitussive activity (p&lt;0.001) in both ammonium hydroxide and acetic acid-induced cough model. The findings in this study validates the folkloric use of Chrysophyllum albidum in alleviating cough.

Theory of the exterior–interior relationship between the lungs and the large intestine to explore the mechanism of Eriobotrya japonica leaf water extract in the treatment of cough variant asthma

Ethnopharmacological relevanceEriobotrya japonica (Thunb.) Lindl leaf (EJL) is used as a traditional Chinese medicine. E. japonica is a member of the Rosaceae family. EJL suppresses cough and relieves asthma and is widely used to treat lung diseases. In the present study, guided by the traditional Chinese medicine theory of the exterior–interior relationship between the lungs and the large intestine, the pathogenesis of cough variant asthma (CVA) and the treatment mechanism of EJL on CVA were explored. Aim of the studyThis study aimed to explore the airway remodeling effects of EJL in CVA from the perspective of the intestinal flora and the matrix metallopeptidase 9/tissue inhibitor of metalloproteinases-1 (MMP-9/TIMP-1) pathway. Materials and methodsThe oleanolic acid and ursolic acid contents in EJL were measured by high-performance liquid chromatography (HPLC) to ensure the quality of EJL. BALB/c mice were used to establish a CVA model through ovalbumin (OVA) sensitization and atomization. EJL (at 5, 10, or 20 g/kg/day) was intragastrically administered. The body weight, ratio of total bronchial wall area (WAt) to bronchial basement membrane perimeter (Pbm) (WAt/Pbm), the number of coughs, and cough latency were measured. The pathological changes of the lung tissue were analyzed by hematoxylin and eosin (HE) staining. The expression of α-smooth muscle actin (α-SMA) was measured by immunohistochemistry (IHC). The expressions of MMP-9 and TIMP-1 were detected in the lung tissue by reverse transcription quantitative polymerase chain reaction (RT-PCR) and Western blot analysis. Additionally, an Illumina Hiseq platform was used for 16S ribosomal DNA (16S rDNA) high-throughput sequencing to detect the intestinal flora in feces samples. ResultsThe results confirmed the positive effects of EJL on CVA. After administration of EJL, the number of coughs and the WAt/Pbm ratio decreased, the cough latency was prolonged, body weight was increased, and the general status was better than that of the CVA model mice. HE staining revealed that EJL decreased inflammatory cell infiltration and improved the histopathological structure of the lung tissue. EJL also showed significant inhibitory effects on the expression of α-SMA, MMP-9, and TIMP-1 and normalized the intestinal flora to a certain extent. ConclusionsThe results demonstrated that EJL alleviated airway remodeling of CVA mice, which might be related to the inhibition of the MMP-P/TIMP-1 pathway and the regulation of intestinal flora.

Anti-asthma and antitussive effects of a fermented extract of a mixture of Ramulus mori, Anthriscus sylvestris, and Salvia plebeian.

Respiratory immunity is getting more important recently due to outbreak of respiratory diseases and increasing the concentration of fine dust. The aim of this study was to investigate respiratory protection effect of a fermented extract of medicinal plants (FEMP) containing Ramulus mori, Salvia plebeia, and Anthriscus sylvestris. The expression levels of IL-8 and IL-17 in LPS/poly-L-arginine (PLA) and FEMP-cotreated A549 cells were lower than those in LPS/PLA only-treated cells. The levels of IgE, IL-17, and IL-4 in the bronchoalveolar lavage fluid (BALF) and serum of FEMP-treated mice with ovalbumin/LPS-induced asthma were lower than the control levels. The lung inflammation score and the number of inflammatory cells in the BALF decreased by FEMP treatment. In the citric acid-induced coughing guinea pig, the FEMP treatment decreased the number of coughs. Therefore, FEMP shows anti-asthmatic and antitussive activities without hepatotoxicity and can be used as a compound aiming to improve respiratory health.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10068-021-00955-3.

An ensemble learning approach to digital corona virus preliminary screening from cough sounds

This work develops a robust classifier for a COVID-19 pre-screening model from crowdsourced cough sound data. The crowdsourced cough recordings contain a variable number of coughs, with some input sound files more informative than the others. Accurate detection of COVID-19 from the sound datasets requires overcoming two main challenges (i) the variable number of coughs in each recording and (ii) the low number of COVID-positive cases compared to healthy coughs in the data. We use two open datasets of crowdsourced cough recordings and segment each cough recording into non-overlapping coughs. The segmentation enriches the original data without oversampling by splitting the original cough sound files into non-overlapping segments. Splitting the sound files enables us to increase the samples of the minority class (COVID-19) without changing the feature distribution of the COVID-19 samples resulted from applying oversampling techniques. Each cough sound segment is transformed into six image representations for further analyses. We conduct extensive experiments with shallow machine learning, Convolutional Neural Network (CNN), and pre-trained CNN models. The results of our models were compared to other recently published papers that apply machine learning to cough sound data for COVID-19 detection. Our method demonstrated a high performance using an ensemble model on the testing dataset with area under receiver operating characteristics curve = 0.77, precision = 0.80, recall = 0.71, F1 measure = 0.75, and Kappa = 0.53. The results show an improvement in the prediction accuracy of our COVID-19 pre-screening model compared to the other models.

Fentanyl versus Remifentanil for Cough Suppression and Recovery after Video-Assisted Thoracic Surgery.

BackgroundVarious methods have been used to reduce postoperative pain after thoracic surgery. However, these methods may affect the patient’s respiratory response and delay recovery from anesthesia. We aimed to evaluate the effects of fentanyl and remifentanil during extubation after video-assisted thoracic surgery (VATS).MethodsThis study included 45 randomly-selected male patients who underwent VATS for pneumothorax between July 2011 and August 2012. We divided the participants into 3 groups the F group, which received a bolus injection of 1.0 µg/kg of fentanyl; the R1 group, which received a 0.04 µg/kg/min remifentanil infusion; and the R2 group, which received a 0.08 µg/kg/min remifentanil infusion. Hemodynamics, pain, cough, consciousness level, and nausea were assessed for each group.ResultsThe number and severity of coughs were lower in the R1 and R2 groups than in the F group, and there were no differences between the R1 and R2 groups. Respiratory depression and loss of consciousness were not observed in any of the patients, and there were no differences in hemodynamics.ConclusionIn comparison with fentanyl, remifentanil did not result in a wide fluctuation of blood pressure and heart rate upon emergence from general anesthesia. Moreover, remifentanil contributed to cough suppression and postoperative pain control. Remifentanil seems to be a safe and effective analgesic after VATS.

Stimulation of Upper Airway Afferents with Capsaicin and Section of the Superior Laryngeal Nerve Modulate Mechanically Induced Coughing from the Tracheobronchial Airways in Male But Not Female Cats

Airway diseases that induce coughing often involve perturbation of sensory feedback from both the upper and lower airways. We speculated that stimulation of upper airway TRPV-1 receptors with capsaicin would enhance coughing induced from the tracheobronchial airways. Further, we hypothesized that this enhancement would be eliminated by section of the superior laryngeal nerves, a primary sensory pathway from the larynx. Cats of either sex (n=5 males, 5 females) were anesthetized, tracheotomized and allowed to spontaneously breathe. The upper airway was isolated by sealing the mouth around a cannula and inserting a port into the upper trachea rostral to the tracheal cannula. Humidified air or humidified air plus capsaicin (55 mM, ultrasonic nebulizer) (500 ml/min) was passed into the mouth and out the trachea at the level of the 4th tracheal ring. Parasternal and abdominal muscle EMGs were recorded along with esophageal pressure. Cough was elicited by mechanical stimulation of the tracheobronchial airways with a flexible cannula. Aerosolization of capsaicin into the upper airway had no effect on cough number in males or females. In males but not females, SLN section resulted in an increase in cough number of approximately 20% that was not affected by capsaicin administration. Esophageal pressure, parasternal and abdominal muscle EMGs all significantly increased by up to 50% during capsaicin administration in males but not females. These effects in males were eliminated by section of the superior laryngeal nerves (SLN), whereas SLN section had no effect on esophageal pressure or respiratory muscle EMG magnitudes during coughing in females. These results support a complex and sex specific role for SLN afferents in the regulation of tracheobronchial cough. In males, elimination of SLN afferent feedback disinhibits cough number but blocks the enhancement of cough intensity by capsaicin-sensitive afferents in the upper airways. Given that our method of administration exposed the entire upper airway to capsaicin, it is possible that our results revealed multiple actions of upper airway afferents traveling in SLN and non-SLN pathways. The role of non-SLN mediated upper airway afferents in the regulation of cough is poorly understood. Our results suggest that in an animal model, the regulation of cough from the lower airways in males significantly differs than in females.

Antitussive Activity of Herbal Cough Medicine on Guinea Pigs (Cavia porvellus)

This study aims to investigate the antitussive activity of herbal cough medicine containing combined herbal extracts of Echinacea purpurea, Sambucus nigra (Black Elderberry), Glycyrrhiza glabra (licorice), Vitex trifolia (Indian wild pepper), and Zingiber officinale (ginger). Antitussive assays were conducted on male Dunkin-Hartley albino guinea pigs (Cavia cobaya), which are divided into 5 groups, each with 8 individuals. These 5 groups were assigned for negative control group (treated with CMC-Na 0.5%), a positive control group (treated with Dextromethorphan 20 mg/kg BW), and three groups receiving herbal medicine with 3 different doses (Group I: 145 mg/kg BW, Group II: 290 mg/kg BW; Group III: 580 mg/kg BW, respectively). The antitussive activity was evaluated by using a citric acid-induced cough assay. For baseline level, 20 % m/v liquid citric acid was exposed using a nebulizer for 10 min, then the number of coughs in 15 min was counted. Sixty (60) minutes after oral administration of the tested herbal cough medicine, the number of citric acid-induced coughs was counted again to see the effect of herbal cough medicine to reduce cough. The number of coughs before and after herbal administration was calculated to obtain antitussive activity, represented by the percentage of cough suppression (PCS). Average PCS for each treatment group is then compared to control positive Dextromethorphan 20 mg/kg BW and control negative CMC-Na 0.5%. Data are analyzed by applying the one-way ANOVA method, which is followed by conducting a Tukey’s Test to discover differences between groups at 95% level of confidence. In terms of the percentage of cough suppression (PCS), treatment doses at 145mg/kg BW, 290 mg/kg BW and 580 mg/kg BW result in 58.48% ± 8.60% (Group I); 58.69% ± 7.96% (Group II); 59.21% ± 8.79% (Group III) PCS, respectively, which insignificantly differ to treatment with Dextromethorphan dose (66.99% ± 9.63 with p &gt; 0.05, implicating that the herbal cough medicine has comparable effect with dextromethorphan in the doses used in this study.

Intra-Arterial, but Not Intrathecal, Baclofen and Codeine Attenuates Cough in the Cat.

Centrally-acting antitussive drugs are thought to act solely in the brainstem. However, the role of the spinal cord in the mechanism of action of these drugs is unknown. The purpose of this study was to determine if antitussive drugs act in the spinal cord to reduce the magnitude of tracheobronchial (TB) cough-related expiratory activity. Experiments were conducted in anesthetized, spontaneously breathing cats (n = 22). Electromyograms (EMG) were recorded from the parasternal (PS) and transversus abdominis (TA) or rectus abdominis muscles. Mechanical stimulation of the trachea or larynx was used to elicit TB cough. Baclofen (10 and 100 μg/kg, GABA-B receptor agonist) or codeine (30 μg/kg, opioid receptor agonist) was administered into the intrathecal (i.t.) space and also into brainstem circulation via the vertebral artery. Cumulative doses of i.t. baclofen or codeine had no effect on PS, abdominal muscle EMGs or cough number during the TB cough. Subsequent intra-arterial (i.a.) administration of baclofen or codeine significantly reduced magnitude of abdominal and PS muscles during TB cough. Furthermore, TB cough number was significantly suppressed by i.a. baclofen. The influence of these drugs on other behaviors that activate abdominal motor pathways was also assessed. The abdominal EMG response to noxious pinch of the tail was suppressed by i.t. baclofen, suggesting that the doses of baclofen that were employed were sufficient to affect spinal pathways. However, the abdominal EMG response to expiratory threshold loading was unaffected by i.t. administration of either baclofen or codeine. These results indicate that neither baclofen nor codeine suppress cough via a spinal action and support the concept that the antitussive effect of these drugs is restricted to the brainstem.

Antitussive, Antioxidant, and Anti-Inflammatory Effects of a Walnut (Juglans regia L.) Septum Extract Rich in Bioactive Compounds.

The antitussive, antioxidant, and anti-inflammatory effects of a walnut (Juglans regia L.) septum extract (WSE), rich in bioactive compounds were investigated using the citric acid aerosol-induced cough experimental model in rodents. Wistar male rats were treated orally for three days with distilled water (control), codeine (reference), and WSE in graded doses. On the third day, all rats were exposed to citric acid aerosols, the number of coughs being recorded. Each animal was sacrificed after exposure, and blood and lung tissue samples were collected for histopathological analysis and the assessment of oxidative stress and inflammatory biomarkers. The results of the experiment showed a significant antitussive effect of WSE, superior to codeine. This activity could be due to cellular protective effect and anti-inflammatory effect via the stimulation of the antioxidant enzyme system and the decrease of IL-6 and CXC-R1 concentration in the lung tissue of WSE-treated animals. The antioxidant and anti-inflammatory effects of WSE were confirmed by biochemical assays and histopathological analysis. This is the first scientific study reporting the antitussive effect of walnut septum, a new potential source of non-opioid antitussive drug candidates, and a valuable bioactive by-product that could be used in the treatment of respiratory diseases.