Control Of Breathing Research Articles

Recovery model for minimally invasive central cannulation, cardiopulmonary bypass, and cardioplegic arrest in quadrupeds.

Objectives: Sternotomy is rarely performed for veterinary therapeutic or recovery models in quadrupeds because of difficulties with breathing, ambulation, and pain control. Central cannulation for cardiopulmonary bypass (CPB) is infrequent and typically performed through full thoracotomies. Experienced clinical surgeons and perfusionists should provide guidance for new therapeutic interventions and translational research. We sought to develop, validate, and detail a contemporary model for minimally-invasive central cannulation, CPB, and cardioplegic arrest. Methods: After induction of anesthesia and sterile preparation, a right second-interspace parasternal mini-thoracotomy was performed, the ascending aorta was cannulated using Seldinger technique, and a cardioplegia needle was placed. A dual-stage cannula was introduced through the right atrial appendage and CPB commenced. The aorta was clamped and Buckberg 4:1 induction cardioplegia was administered. Arrest was maintained for 30minutes. CPB was discontinued after 2hours and the great vessels were decannulated. Hemostasis was achieved and the wound was closed. Initial recovery was accomplished in intensive care with subsequent transfer to the vivarium.Results: Ten consecutive Yorkshire swine (45 ± 5kg) were minimally invasively placed on CPB including cardioplegic arrest using central cannulation through a right parasternal mini-thoracotomy. There was no operative or late mortality. Morbidity appeared minimal. Planned euthanasia and scheduled necropsy were performed to exclude clinically-occult major complications. None were identified. Following initial supervision, veterinary and resident surgeons completed the procedures autonomously with excellent results.Conclusion: The described protocols should facilitate safe veterinary cardiac surgical care and humane translational research.

Why do pacifiers/dummies have a protective effect in sudden infant death Syndrome? A new hypothesis

The American Academy of Pediatrics recommends pacifier/dummy use to help prevent sudden infant death syndrome (SIDS). This recommendation is based on studies that have shown pacifier use reduces the risk of SIDS even under conditions regarded as increasing the risk of SIDS. Several unrelated mechanistic explanations have been used to explain this. These prior suggested mechanisms purported to underly the observed protective effect of pacifiers have not proven satisfactory and highlight the need for a more plausible explanation. Pacifier use is associated with increased salivary production. Saliva contains numerous antibacterial compounds that could provide a protective effect against bacterial colonisation. Infection is considered a key player in SIDS pathogenesis given that most SIDS risk factors relate to or align with infection, whereas mainstream research focusses on central homeostatic control of breathing, arousal and heart function. These, however, lack association with risk factors. Given infection is significant in the SIDS story, the increased production and antibacterial effect of saliva could provide an alternative mechanism worthy of consideration in the context of known preventable risk factors in the drive to reach a better understanding of SIDS pathogenesis and further decrease the incidence of SIDS.

Affective Touch in Preterm Infant Development: Neurobiological Mechanisms and Implications for Child-Caregiver Attachment and Neonatal Care.

Affective touch is crucial in infant development, particularly in regulating emotional, cognitive, and physiological processes. Preterm infants are often deprived of essential tactile stimulation owing to their early exposure to the external environment, which may affect long-term developmental outcomes. This review aimed to examine the neurobiological mechanisms of affective touch and highlight effective interventions, such as skin-to-skin contact (SSC) and kangaroo care (KC), to promote development in preterm infants. This review summarizes recent studies in the literature on affective touch, the role of C-tactile fibers, and the effects of tactile interventions in neonatal care. Studies were selected based on their relevance to the care and development of preterm infants, with a focus on physiological and neurodevelopmental outcomes. Key interventions, including SSC and massage therapy, are discussed in relation to their effectiveness in the neonatal intensive care unit (NICU). The results suggest that affective touch, mainly through activation of tactile C-fibers, improves caregiver-infant bonding, reduces stress responses, and supports neurodevelopment in preterm infants. Interventions such as SSC and KC have also been shown to improve physiological regulation in these infants, including heart rate, breathing, and temperature control while promoting emotional regulation and cognitive development. Affective touch is a key component of early development, particularly in preterm infants admitted to the NICU. Integrating tactile interventions such as SSC and KC into neonatal care practices may significantly improve long-term developmental outcomes. Future research should explore the epigenetic mechanisms underlying affective touch and further refine tactile interventions to optimize neonatal care.

A top-down slow breathing circuit that alleviates negative affect in mice.

Although breathing is primarily automatic, its modulation by behavior and emotions suggests cortical inputs to brainstem respiratory networks, which hitherto have received little characterization. Here we identify in mice a top-down breathing pathway from dorsal anterior cingulate cortex (dACC) neurons to pontine reticular nucleus GABAergic inhibitory neurons (PnCGABA), which then project to the ventrolateral medulla (VLM). dACC→PnC activity correlates with slow breathing cycles and volitional orofacial behaviors and is influenced by anxiogenic conditions. Optogenetic stimulation of the dACC→PnCGABA→VLM circuit simultaneously slows breathing and suppresses anxiety-like behaviors, whereas optogenetic inhibition increases both breathing rate and anxiety-like behaviors. These findings suggest that the dACC→PnCGABA→VLM circuit has a crucial role in coordinating slow breathing and reducing negative affect. Our study elucidates a circuit basis for top-down control of breathing, which can influence emotional states.

Interactions between arousal state and CO₂ determine the activity of central chemoreceptor neurons that drive breathing.

The homeostatic regulation of pulmonary ventilation, and ultimately arterial PCO2, depends on interactions between respiratory chemoreflexes and arousal state. The ventilatory response to CO2 is triggered by neurons in the retrotrapezoid nucleus (RTN) that function as sensors of central pH, which can be identified in adulthood by expression of Phox2b and Neuromedin B. Here we examine the dynamic response of genetically-defined RTN neurons to hypercapnia and arousal state in freely-behaving adult male and female mice using the calcium indicator jGCaMP7 and fiber photometry. We found that hypercapnia vigorously activates RTN neurons with a low CO2 recruitment threshold and with response kinetics that match respiratory activity whereas hypoxia had little effect. RTN activity increased transiently during wakefulness and respiratory-related arousals, rose persistently during REM sleep and their CO2 response persisted under anesthesia. Complementary studies using inhibitory optogenetics show that RTN activity supports eupneic breathing under anesthesia as well as during states of high arousal, but their activity is redundant for voluntary breathing patterns. Collectively, this study demonstrates that CO2-activated RTN neurons are exquisitely sensitive to arousal state, which determines their contribution to alveolar ventilation in relation to arterial PCO2 Significance statement Respiratory chemoreceptors stimulate neural respiratory motor output to regulate arterial PCO2 and PO2, thereby maintaining optimal gas exchange. Central chemoreceptor neurons expressing Phox2b and Neuromedin B in the Retrotrapezoid Nucleus (RTN) are required for the hypercapnia ventilatory response. However, the dynamic activity of RTN neurons in conditions of normal and elevated carbon dioxide has not been described in unanesthetized conditions. Here, we use a genetically-encoded calcium indicator to demonstrate that RTN neurons exquisitely sensitivity to hypercapnia and variations in arousal and sleep-state in freely-behaving mice. This work has implications for understanding the central control of breathing across arousal-states, particularly during sleep and anesthesia.

Research on the Psychological State of Brass Instrument Performers from the Perspective of Emotion Regulation

This article explores the psychological state of brass instrument performers from the perspective of emotion regulation, focusing on the positive impacts of emotional regulation strategies such as cognitive reappraisal, breathing control, and mindfulness training on performers’ psychological well-being. Specific applications of these strategies are proposed for performance preparation, stage performances, and daily practice. Research results indicate that the effective use of emotion regulation strategies can alleviate performers’ anxiety, enhance psychological stability, and improve performance quality, providing practical psychological intervention pathways for brass instrument players.

Comparing interfractional stability of heart dose among three breath-hold radiotherapy techniques in breast cancer

IntroductionBreath holding can reduce the cardiac dose in radiotherapy for left-sided breast cancer. We evaluated whether any of the existing commonly used breath-hold techniques was superior in maintaining a more reproducible mean heart dose (MHD) during treatment. Methods and MaterialsThis was a single-institution, interventional, non-randomized, three-armed prospective trial, comparing the reproducibility of MHD in breath-hold radiotherapy using voluntary deep inspiration breath hold (vDIBH), active breathing control (ABC) and surface guided radiotherapy (SGRT). The MHD were determined based on the anatomy in planning computer tomography and each weekly cone beam computer tomography (CBCT) during radiotherapy. The reproducibility of MHD was measured by calculating the interfractional variation of MHD (represented by the standard deviation) across the CBCT, and the difference between the cumulative MHD at CBCT and at planning CT. These two measures of reproducibility were then compared among vDIBH, ABC and SGRT. ResultsOf the 55 patients recruited, 19 had ABC, 20 had SGRT and 16 had vDIBH. SGRT was associated with a slightly greater interfractional variation of the MHD, compared with vDIBH (Least Square Means (LSM): 28.8cGy (SGRT) vs 10.5cGy (vDIBH), p=0.0052) and ABC (LSM: 28.8cGy (SGRT) vs 15.1cGy (ABC), p=0.026). In the SGRT group, the cumulative MHD at CBCT was lower than that at planning CT (mean difference: -22.1cGy, p=0.013). No such difference existed in vDIBH and ABC. In terms of the reproducibility of cumulative MHD at CBCT as compared to that in planning CT, there was no significant difference between vDIBH (mean: -12.1cGy), ABC (mean: -4.8cGy) and SGRT (mean: -22.1cGy) (p-value for pairwise comparison all >0.1). ConclusionSGRT was associated with a slightly greater interfractional variation of MHD compared with vDIBH and ABC, but the difference may not be clinically significant. All three breath-hold techniques were broadly comparable in their reproducibility of MHD at CBCT relative to the planning CT.

Incidence of cardiovascular diseases among breast cancer patients: a nationwide registry study 2013-2020

Abstract Background and aims There is evidence to suggest that breast cancer (BC) treatment is associated with an increased risk of developing cardiovascular disease (CVD). Several countries have introduced clinical measures to reduce the impact of breast cancer treatment on cardiovascular function including activated breathing control during radiotherapy, lower radiation doses, and maximum anthracycline doses. The overall aim of this study was therefore to investigate whether breast cancer patients still exhibit higher rates of cardiovascular disease than the general population. Methods We conducted a registry-based cohort study using linked data from four nationwide health registries. Out study population included all Norwegian patients diagnosed with BC between 2013-2020 and matched them by age to 10 controls without BC. Health outcomes were measured from 2008 to 2021. We estimated the cumulative incidence from index date, for ten selected CVDs. For BC patients, the index date was defined as date of BC diagnosis. For controls, the index date was defined as the date of BC diagnosis for the matched BC patient. A wash-out period of 5 years was applied to identify incident cases of CVD. Results The study population included 27,535 patients with BC and 269,9994 matched controls. Median age in both groups was 62 years (IQR: 20). Prior to index date, there were no significant differences in the prevalence of heart valve disease, chronic ischemic heart disease heart failure and peripheral vascular disease in BC patients compared to controls (p>0.05) (Table 1). Hypertensive heart disease, pulmonary embolism, atrial fibrillation, and other cardiac arrythmias were more prevalent in BC patients, while angina pectoris and acute myocardial infarction were more prevalent among controls. After the index date, the incidence proportion for heart valve disease, hypertensive heart disease, pulmonary embolism, atrial fibrillation, other cardiac arrythmias, and heart failure were higher in BC patients compared to controls (p<0.001) (Table 2). No significant differences were found for angina pectoris, acute myocardial infarction, chronic ischemic heart disease, and peripheral vascular disease. Conclusion Breast cancer is still associated with an increased risk of developing several CVDs in current clinical practice, compared to matched controls without breast cancer.Baseline characteristicsIncidence of CVD

Prospective Trial on the Impact of Weekly Cone Beam Computed Tomography-Guided Correction on Mean Heart Dose in Breast Cancer Breath-Hold Radiation Therapy

PurposeSurface-guided radiotherapy (SGRT) in breast cancer radiotherapy (RT) may decrease the need for image guidance such as cone beam computed tomography (CBCT). The goal of this study is to evaluate the impact of CBCT image guidance on the cumulative and interfractional variation of mean heart dose (MHD) during breath-hold radiotherapy in patients with breast cancer. We hypothesize that weekly CBCT is not necessary in SGRT-assisted breath-hold, but is still needed in patients treated with voluntary deep inspiration breath hold (vDIBH) and active breathing control (ABC) to maintain a stable MHD. Methods and materialsThis is a prospective, single-centre trial that sequentially assigned breast cancer patients to adjuvant RT 40-50Gy in 15-25 fractions using vDIBH, ABC or SGRT to reproduce the breath-hold. The MHD was estimated on each of the weekly CBCT images before and after online correction. The cumulative and interfractional variation of MHD, which were represented by the average and standard deviation (SD) of MHD in each patient, were compared in the series of CBCT before and after online correction, to evaluate whether online CBCT-guided correction could lead to a more reproducible MHD. ResultsFifty-five patients were included (vDIBH=16, ABC=19, SGRT=20). CBCT-guided online correction was associated with a significant decrease in the interfractional variation of MHD in vDIBH (SD difference: 22.6cGy, p=0.0389) and ABC (SD difference: 9.9cGy, p=0.0262), but not in SGRT (p=0.2272). CBCT-guided online correction had no impact on the cumulative MHD in all three groups. ConclusionsThis study demonstrated that CBCT-guided online correction could reduce the interfractional variation of MHD in ABC or vDIBH. When SGRT was available, CBCT-guided correction had no impact on the stability of MHD across the treatment fractions. Future studies may explore whether the CBCT frequency could be reduced to less than weekly in SGRT, to decrease treatment time and the radiation dose associated with CBCT.

Altered control of breathing in a rat model of allergic lower airway inflammation.

Obstructive sleep apnea (OSA) is highly prevalent in patients with asthma. Asthma, dose-dependently to its duration, promotes incident OSA, suggesting that asthma plays a role in OSA pathogenesis. We hypothesized that asthma-related inflammation alters breathing control mechanisms, specifically the carotid chemoreflex. Accordingly, we measured hypoxic ventilatory responses (HVR) in awake, unrestrained, ovalbumin (OVA)-sensitized Brown Norway rats and compared them with responses in sham-sensitized (SALINE) controls. To differentiate the role of allergic inflammation from bronchoconstriction, we repeated hypoxic ventilatory response (HVR) after administration of formoterol, a long-acting bronchodilator. Blood and bronchoalveolar lavage (BAL) fluid were collected for quantification of inflammatory cytokines. The rise in ventilatory equivalent for O2 evoked by acute exposure to hypoxia was augmented following sensitization by OVA, whereas it remained stable after SALINE. This augmentation was driven by increased breathing frequency with no change in tidal volume. Tachypneic hyperventilation in normoxia was also observed with OVA. Neither the increased HVR nor excessive normoxic ventilation was affected by formoterol, suggesting that they were not secondary to lung mechanical constraints. Higher levels of inflammatory cytokines were observed in BAL fluid and serum of OVA versus SALINE. In OVA, serum interleukin-5 levels significantly correlated with change from baseline in ventilatory responses to severe hypoxia ([Formula: see text], 0.09). These observations are consistent with inflammation-induced enhancement of carotid chemoreflex function, i.e., increased controller gain, and they suggest a possible role for asthma-related allergic inflammation in the ventilatory instability known to promote upper airway collapse and sleep apnea in humans.NEW & NOTEWORTHY Asthma is a risk factor for obstructive sleep apnea (OSA); however, the mechanisms are incompletely understood. In a rat model of allergic inflammation associated with asthma, we found that ventilation in normoxia and ventilatory responses to hypoxia were markedly enhanced and related with systemic inflammation. These alterations indicating carotid chemoreflex sensitization, known to promote ventilatory instability during sleep in humans, may contribute to the increased OSA risk in asthma.

All-Optical Control of Bubble and Skyrmion Breathing.

Controlling the dynamics of topologically protected spin objects by all-optical means promises enormous potential for future spintronic applications. Excitation of bubbles and skyrmions in ferrimagnetic [Fe(0.35 nm)/Gd(0.40 nm)]_{160} multilayers by ultrashort laser pulses leads to a periodic modulation of the core diameter of these spin objects, the so-called breathing mode. We demonstrate versatile amplitude and phase control of this breathing using a double excitation scheme, where the observed dynamics is controlled by the excitation delay. We gain insight into both the timescale on which the breathing mode is launched and the role of the spin object size on the dynamics. Our results demonstrate that ultrafast optical excitation allows for precise tuning of the spin dynamics of trivial and nontrivial spin objects, showing a possible control strategy in device applications.

Lung mechanics in juvenile and adult Chelonoidis carbonarius.

Testudines possess a rigid shell that influences the mechanics of the respiratory system. We studied respiratory mechanics in the terrestrial red-footed tortoise Chelonoidis carbonarius (Cryptodira), comparing juvenile individuals with a less ossified and more flexible carapace with adults with a well-ossified rigid shell. Combined with these ontogenetic differences, we analyzed respiratory system mechanics with animals in a supine and a prone position, as well as in the isolated lungs, to evaluate the impact of the viscera on breathing mechanics. To do so, we used established protocols to measure pulmonary volume (i.e. resting, VLr; and maximum, VLm), static (Cstat) and dynamic (Cdyn) compliance, and the work of breathing (W). We observed that isolated lungs displayed increased VLr, VLm, Cstat and Cdyn and decreased W. Additionally, pulmonary volume, compliance and W were affected by evaluated position, such as a smaller VLr in a supine position. Cdyn and W showed a volume dependency while frequency had less influence on these variables. At similar levels of ventilation, juveniles showed a lower W than adults when standardized by body mass, but similar W when standardized by VLr. Clear ontogenetic changes could be observed in breathing mechanics between juvenile and adult C. carbonarius. While these differences might largely be explained by variation in shell ossification, other explanations such as differences in visceral proportions or developmental degree of the post-pulmonary septum should also be taken into account.

The Influence of Kinesiology Tape on Posture and Breathing Mechanics in Healthy Individuals: A Randomized Trial

Background and Purpose: Kinesiology tape (KT) has been used clinically to improve posture, mobility, and muscle strength. Limited research has investigated the effect of KT on respiratory function. The purpose of this study was to explore the effects of KT on posture and breathing in healthy individuals. Methods: Ninety-two adult participants were randomly assigned to a KT, sham tape (ST), or control group. Data collection occurred over 2 sessions. Baseline measurements included chest wall expansion (CWE) at the sternal angle (SA) and xiphoid process (Xi), maximal inspiratory pressure (MIP), and tragus (TWD) and acromion (AWD) to wall distances. Next, KT or ST was applied to the upper back and neck, or no tape was applied based on group assignment. Measurements were then repeated. Participants returned for a final round of measurements 48 hours later. Mixed-measures ANOVAs were used to determine the influence of tape at baseline (T0), immediately post-taping (T1), and 48 hours post-taping (T2). Post hoc analyses used the Tukey method. Results: Analysis showed significant differences between T0 and T1 (P = .004) and between T1 and T2 (P = .004) for AWD on the left. CWE-Xi data showed within group differences T0-T2 (P = .004) and T1-T2 (P = .004). MIP data showed within group differences between T0 and T1 (P = .001), T0 and T2 (P < .001), and T1 and T2 (P < .001). Discussion: KT had a limited and inconsistent impact on posture where there was a decrease in AWD on the left from T0 to T1 and then an increase from T1 to T2. No other changes in posture were found. Taping did not affect CWE at the SA. There was an evident training effect for CWE-Xi and MIP, where all groups saw increases over time. Conclusion: This method of KT application is not supported as an intervention for influencing posture and enhancing inspiratory breathing mechanics in healthy adults. Further investigation of KT in other populations is needed.

Acute respiratory compromise in the NICU

Acute respiratory compromise (ARC) is a significant and frequent emergency in the Neonatal Intensive Care Unit (NICU), characterized by absent, agonal, or inadequate respiration that necessitates an immediate response. The primary etiologies of ARC in neonates can be categorized into upper and lower airway issues, disordered control of breathing, and lung tissue disease. ARC events are particularly dangerous as they compromise oxygen delivery and carbon dioxide removal, potentially leading to cardiopulmonary arrest. Approximately 1 % of NICU admissions experience cardiopulmonary arrest, and ARC is the primary cause of most events. This article provides a comprehensive review of the etiologies of ARC, including anatomical abnormalities, syndromic disorders, airway obstruction, and pulmonary diseases such as bronchopulmonary dysplasia and pneumonia. Management strategies include the use of continuous positive airway pressure, positive pressure ventilation, and advanced interventions like extracorporeal membrane oxygenation (ECMO) in cases of severe respiratory distress. Additionally, quality improvement initiatives aimed at reducing incidents such as unplanned extubations (UE) are discussed, along with emergency responses to ARC, which often require multidisciplinary collaboration and advanced airway management. The article emphasizes the importance of preparedness, training, and structured emergency protocols to ARC in the NICU to optimize patient care.

Prediction of Mortality and Outcome of Various Trauma Scores in Polytrauma Patients.

Background In developing nations, the primary cause of death is trauma, and the prevalence of trauma is increasing as more vehicles are driven. Numerous trauma scoring systems have been created in order to predict the mortality rate and patients with trauma's prognosis. The purpose of the current study was to assess the prognostic ability of various trauma scoring systems for patients' mortality and morbidity in cases involving chest and abdominal injuries, as they are common in the surgery department. Methodology At Ranchi, Jharkhand's Rajendra Institute of Medical Sciences, a prospective observational study was conducted from June 2021 to September 2022. All patients who met the requirements for inclusion were older than 18 and reported chest and abdominal trauma totaling 204. Before any essential therapies, primary care and resuscitation, including airway maintenance, breathing, circulation, and hemorrhage control, were established. A comprehensive clinical evaluation was done based on each patient's needs. Radiological evaluation included chest X-ray and ultrasonography (USG) for chest trauma, whereas USG (FAST) and CT scans were for abdominal trauma. Trauma scores, such as the Revised Trauma Score (RTS), the Trauma Revised Injury Severity Score (TRISS), the New Injury Severity Score (NISS), and the Injury Severity Score (ISS), were computed and examined using IBM Corp. Released 2011. IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp. Results Of the 204 patients, 14.7% were female and 85.3% were male. The age range of 21-30 years old accounted for the largest percentage of cases (28%). 50 percent of injuries were caused by automobile accidents, while 25% were the result of assaults. At 83.8% versus 16.2%, blunt injuries were substantially more common than penetrating ones. In comparison to the chest, the abdomen was more frequently involved. The study's findings demonstrated that, while every trauma scoring was statistically significant in predicting mortality, the New Injury Severity Score (NISS), as well as the Trauma Revised Injury Severity Score (TRISS), became the most effective in predicting mortality (p < 0.0001). Conclusion According to the results, the most precise trauma grading method for chest and abdominal injuries is the Trauma Revised Injury Severity Score (TRISS), even though all other trauma scoring systems are useful in predicting patient outcomes. Surgeons using these metrics to predict outcomes and make well-informed treatment decisions can benefit greatly.

Vglut2-based glutamatergic signaling in central noradrenergic neurons is dispensable for normal breathing and chemosensory reflexes.

Central noradrenergic (NA) neurons are key constituents of the respiratory homeostatic network. NA dysfunction is implicated in several developmental respiratory disorders including Congenital Central Hyperventilation Syndrome (CCHS), Sudden Infant Death Syndrome (SIDS), and Rett Syndrome. The current unchallenged paradigm in the field, supported by multiple studies, is that glutamate co-transmission in subsets of central NA neurons plays a role in breathing control. If true, NA-glutamate co-transmission may also be mechanistically important in respiratory disorders. However, the requirement of NA-derived glutamate in breathing has not been directly tested and the extent of glutamate co-transmission in the central NA system remains uncharacterized. Therefore, we fully characterized the cumulative fate maps and acute adult expression patterns of all three vesicular glutamate transporters (Slc17a7 (Vglut1), Slc17a6 (Vglut2), and Slc17a8 (Vglut3)) in NA neurons, identifying a novel, dynamic expression pattern for Vglut2 and an undescribed co-expression domain for Vglut3 in the NA system. In contrast to our initial hypothesis that NA-derived glutamate is required to breathing, our functional studies showed that loss of Vglut2 throughout the NA system failed to alter breathing or metabolism under room air, hypercapnia, or hypoxia in unrestrained and unanesthetized mice. These data demonstrate that Vglut2-based glutamatergic signaling within the central NA system is not required for normal baseline breathing and hypercapnic, hypoxic chemosensory reflexes. These outcomes challenge the current understanding of central NA neurons in the control of breathing and suggests that glutamate may not be a critical target to understand NA neuron dysfunction in respiratory diseases.

Vglut2-based glutamatergic signaling in central noradrenergic neurons is dispensable for normal breathing and chemosensory reflexes

Central noradrenergic (NA) neurons are key constituents of the respiratory homeostatic network. NA dysfunction is implicated in several developmental respiratory disorders including Congenital Central Hyperventilation Syndrome (CCHS), Sudden Infant Death Syndrome (SIDS), and Rett Syndrome. The current unchallenged paradigm in the field, supported by multiple studies, is that glutamate co-transmission in subsets of central NA neurons plays a role in breathing control. If true, NA-glutamate co-transmission may also be mechanistically important in respiratory disorders. However, the requirement of NA-derived glutamate in breathing has not been directly tested and the extent of glutamate co-transmission in the central NA system remains uncharacterized. Therefore, we fully characterized the cumulative fate maps and acute adult expression patterns of all three vesicular glutamate transporters (Slc17a7 (Vglut1), Slc17a6 (Vglut2), and Slc17a8 (Vglut3)) in NA neurons, identifying a novel, dynamic expression pattern for Vglut2 and an undescribed co-expression domain for Vglut3 in the NA system. In contrast to our initial hypothesis that NA-derived glutamate is required to breathing, our functional studies showed that loss of Vglut2 throughout the NA system failed to alter breathing or metabolism under room air, hypercapnia, or hypoxia in unrestrained and unanesthetized mice. These data demonstrate that Vglut2-based glutamatergic signaling within the central NA system is not required for normal baseline breathing and hypercapnic, hypoxic chemosensory reflexes. These outcomes challenge the current understanding of central NA neurons in the control of breathing and suggests that glutamate may not be a critical target to understand NA neuron dysfunction in respiratory diseases.

Effectiveness of Intercostal Stretch Technique on Pulmonary Conditions: A Narrative Review

Background: The Intercostal Stretch Technique is one of the physiotherapy techniques that is used to solve different respiratory problems. It is used for increasing chest expansion and diaphragm excursion improvement and also intra-thoracic lung volume. Aim: The study aims to evaluate the effectiveness of the intercostal stretch technique. Methodology: A narrative review. In this study, an RCT study was used to review the intervention. Results: Several articles are used to discuss the effectiveness of the intercostal stretch technique. In stable COPD, diaphragmatic breathing and the intercostal stretch technique both work equally well to improve chest expansion and functional capacity while lowering dyspnea. Research has shown that IC stretch outperforms the anterior basal lift technique in lowering heart and respiratory rates while increasing oxygen saturation. According to this study, IC stretching in conjunction with breathing control may improve dynamic lung parameters, particularly FEV1/FVC%, more than breathing control alone. Patients with COPD have an increased functional exercise capacity and reduced dyspnea when aerobic training and respiratory muscle stretching are combined. Conclusion: Different articles demonstrated that IC stretch improved lung function, expired tidal volume, decreased dyspnea, and increased chest expansion.

Meticulous nursing care for coronary CT angiography: A systematic review and meta-analysis of randomized controlled trials.

This study aimed to investigate the effects of meticulous nursing care (MNC) for patients with coronary heart disease undergoing coronary CT angiography (CCTA). We conducted a comprehensive search of the Cochrane Library, PubMed, EMBASE, China National Knowledge Infrastructure, and Wangfang databases from inception to January 1, 2024. Randomized clinical trials (RCTs) evaluating the effects of MNC for CCTA were included. Outcomes assessed included self-rating anxiety scale (SAS), self-rating depression scale (SDS), overall satisfaction of nursing care (OSNC), examination time (ET, min), radiation dose received (RDR, mSv), breathing control time (BCT), and heart rate control time (HRCT).The methodological quality of all included RCTs was evaluated using the Cochrane risk-of-bias tool, while statistical analysis was conducted using RevMan 5.4 software. Six eligible trials involving 1064 patients were included. The results of the meta-analysis showed significant differences in SAS (MD = -2.84, 95% CI [-3.31, -2.37], I2 = 0%, P < .001), SDS (MD = -2.55, 95% CI [-3.51, -1.58], I2 = 0%, P < .001), OSNC (OR = 3.13, 95% CI [1.59, 6.17], I2 = 23%, P = .001), BCT (MD = -23.43, 95% CI [-25.07, -21.80], I2 = 45%, P < .001), HRCT (MD = -20.08, 95% CI [-21.70, -18.46], I2 = 29%, P < .001), ET (MD = -2.31, 95% CI [-2.56, -2.06], I2 = 5%, P < .001), and RDR (MD = -2.11, 95% CI [-2.45, -1.77], I2 = 0%, P < .001). MNC may benefit for patients with coronary heart disease undergoing CCTA. Future studies are still needed to warrant the current findings.

599. ASSESSMENT OF BREATHING MECHANICS IN OESOPHAGEAL CANCER SURVIVORS USING A 3D-MOTION CAPTURE SYSTEM

Abstract Background Traditional open surgery is characterised by an intercostal incision. The associated ribcage injury may precipitate the development of post-thoracotomy-related pain, with impaired respiratory muscle contraction, leading to compromised coughing and decreased lung volumes. These changes in breathing mechanics may precipitate pulmonary complications, occurring in up to 40% of the patients. There is however no data available on the long-term breathing function and its implications on the health-related quality of life following oesophagectomy. This proof-of-concept study aimed to objectively measure breathing movements using a 3D-motion capture system and to understand the impact of surgery on breathing patterns in oesophageal cancer survivors. Methods Oesophageal cancer survivors who were disease-free for at least 1 year postoperatively and healthy controls were included. Participants completed quality-of-life (QoL) questionnaires, including EORTC QLQ-C30, -OG25 and LASORS. Eighty-nine retroreflective markers were affixed to the participants' trunks to measure respiratory movements via the Vicon motion capture system during handheld spirometry performance. The highest spirometry value was recorded for the slow inspiratory (SIVC) and forced expiratory vital capacity (FEVC). Concurrent movement data was obtained from adjacent surface markers connected to the midpoint, allowing evaluation of the total volumetric movement of the trunk, and thoracic and abdominal contributions. Results Eighteen patients (median age 68) and 22 controls (median age 29) were included. Patients exhibited a significantly reduced SIVC alongside decreased chest movement contribution (median 2.4519 litres IQR 0.9270) compared to controls (median 3.1492 litres, IQR 1.8381) (p=0.013). Meanwhile, patients also had significantly lower FEVC with lower abdominal movement (median 1.5134 litres, IQR 0.7852) compared to controls (median 2.1263 litres, IQR 0.8740) (p=0.039). The QoL amongst patients was significantly worse for half of the EORTC domains, including physical functioning, fatigue, dyspnoea, pain and discomfort, and coughing (p&amp;lt;0.05). Additionally, the QoL of patients was consistently lower across all LASOR domains (p&amp;lt;0.05). Conclusion Current data showed lower spirometry parameters and breathing movements amongst oesophageal cancer survivors, suggestive of impaired breathing mechanics. Specifically, chest expansion was compromised during slow inhalation, while abdominal contraction was reduced during forced exhalation. These findings suggest restrictive changes in breathing mechanics