Respiratory Mode Research Articles

Efficacy and safety of spontaneous ventilation technique using dexmedetomidine for rigid bronchoscopic airway foreign body removal in children

In children, removal of an airway foreign body is usually performed by rigid bronchoscopy under general anesthesia. Debate continues regarding the respiratory mode (spontaneous or controlled ventilation) and appropriate anesthetic drugs. Dexmedetomidine has several desirable pharmacologic properties and appears to be a useful agent for airway surgeries. This study evaluates the efficacy of spontaneous ventilation (SV) technique using dexmedetomidine for bronchoscopic removal of foreign bodies in children. Eighty pediatric patients undergoing rigid bronchoscopy for airway foreign body removal were randomly divided into two groups. In the SV group, dexmedetomidine (4 μg∙kg(-1)) and topical lidocaine (3-5 mg∙kg(-1)) were administered and the patients were breathing spontaneously throughout the procedure. In the manual jet ventilation (MJV) group, anesthesia was induced with fentanyl (2 μg∙kg(-1)), propofol (3-5 mg∙kg(-1)), and succinylcholine (1 mg∙kg(-1)), and MJV was performed. The success rates of foreign body removal, the incidence of body movement and other perioperative adverse events, and hemodynamic changes were similar between the two groups. The SV patients required longer stays in the postanesthesia care unit (P < 0.01) but experienced less coughing (P = 0.029) in the recovery room. Dexmedetomidine may provide appropriately deep anesthesia and ideal conditions for rigid bronchoscopic airway foreign body removal without respiratory depression or hemodynamic instability.

Thermus oshimai JL-2 and T. thermophilus JL-18 genome analysis illuminates pathways for carbon, nitrogen, and sulfur cycling.

The complete genomes of Thermus oshimai JL-2 and T. thermophilus JL-18 each consist of a circular chromosome, 2.07 Mb and 1.9 Mb, respectively, and two plasmids ranging from 0.27 Mb to 57.2 kb. Comparison of the T. thermophilus JL-18 chromosome with those from other strains of T. thermophilus revealed a high degree of synteny, whereas the megaplasmids from the same strains were highly plastic. The T. oshimai JL-2 chromosome and megaplasmids shared little or no synteny with other sequenced Thermus strains. Phylogenomic analyses using a concatenated set of conserved proteins confirmed the phylogenetic and taxonomic assignments based on 16S rRNA phylogenetics. Both chromosomes encode a complete glycolysis, tricarboxylic acid (TCA) cycle, and pentose phosphate pathway plus glucosidases, glycosidases, proteases, and peptidases, highlighting highly versatile heterotrophic capabilities. Megaplasmids of both strains contained a gene cluster encoding enzymes predicted to catalyze the sequential reduction of nitrate to nitrous oxide; however, the nitrous oxide reductase required for the terminal step in denitrification was absent, consistent with their incomplete denitrification phenotypes. A sox gene cluster was identified in both chromosomes, suggesting a mode of chemolithotrophy. In addition, nrf and psr gene clusters in T. oshmai JL-2 suggest respiratory nitrite ammonification and polysulfide reduction as possible modes of anaerobic respiration.

Dental consequences of mouth breathing in the pediatric age group

Background: The presence of mouth breathing (MB) in pediatric patients is a relatively common fact and may result in a series of changes characteristic of occlusal features. In the presence of unbalanced muscular activity, dental inter-arch relationship is the important parameter to understand the patient's occlusion. Therefore, it is important to assess the occurrence of occlusal disorders among MB children. Aim: The present study is undertaken to verify the dental occlusal characteristics with extent of MB and nasal breathing in a pediatric patient. Materials and Methods: A cross-sectional study was performed to assess the association of changed mode of respiration with occlusal variables from dental cast. Ninety-two subjects, of whom 40 were mouth breathers and 52 were nasal breathers, of 7-11 years of age were submitted to clinical examination and dental cast analysis. Results: Mouth breathers demonstrated considerable increase in palatal height and increased overjet, and statistically significant narrowing of the upper arch at the level of the molar. Conclusion: Changed mode of respiration during critical growth periods in children has a higher tendency for increased palatal height and overjet, reduced overbite and maxillary intermolar width.

Aspectos do sistema estomatognático pré e pós-adenotonsilectomia

To verify the speech therapy aspects of the stomatognathic system, including phonoarticulatory structures (lips, tongue, and soft palate) and swallowing, respiratory, speech, and phonation (vocal quality and resonance) functions, before and after undergoing adenotonsillectomy. The study included 22 children, 17 males and 5 females, aged between 5 and 10 years, suffering from hypertrophy of palatine and adenoid tonsils, with surgical indication for adenotonsillectomy and with no previous speech therapy. The speech-language pathology evaluation was performed before surgery and during the period between 1 and 6 months after adenotonsillectomy. It consisted of an evaluation of structures (lips, tongue, and soft palate) and of swallowing (liquid), respiration (mode), speech, and phonation (voice quality and resonance) functions. To evaluate vocal quality and resonance, 15 participants with the postoperative evaluation carried out in a period from 1 to 2 months were considered. There were differences regarding nasal respiratory mode, lips closed at rest posture, changed tongue tonus, adequate mobility of the soft palate, changed tongue posture during liquid swallowing, and absence of interposition compensatory mechanism of lips in swallowing. Reduction in the frequency of distortion processes was also found. With regard to speech, little improvement in vocal quality and resonance was seen. Following adenotonsillectomy, some structures and functions can spontaneously readapt or improve. However, most children needed to be referred to speech therapy for readapting stomatognathic structures and the assessed functions.

89: Neonatal respiratory morbidity and mode of delivery between 34+0 and 36+6 weeks of gestation

89: Neonatal respiratory morbidity and mode of delivery between 34+0 and 36+6 weeks of gestation

Peptide mapping of polymorphic myosin heavy chain isoforms in different muscle types of some freshwater teleosts

A modified SDS-PAGE system has been employed to resolve polymorphic myosin heavy chain (MyHC) isoforms in different muscle types of three freshwater teleosts displaying different modes of respiration, adaptive features and life styles. Investigated species include accessory air-breather Channa punctata along with exclusive aquatic breather major carps Labeo rohita and Catla catla. All the selected species show specificity and expressivity of at least three MyHC isoforms, one each in red, head and pectoral muscles. Chymotryptic peptide maps unambiguously support substructural individuality of each MyHC isoforms with the type-specific dispersal of chymotryptic cleavage sites. Specific Ca(2+)- and Mg(2+)-ATPase activities of natural actomyosin (NAM) of lateral line red muscle of C. punctata were low and less sensitive to pH, but sensitive to KCl concentrations between 0.05 and 0.15M. In comparison, the specific enzymatic activities of NAM of red muscle from the carps (L. rohita and C. catla) were substantially high with prominent peaks at pH 7.5 and near insensitivity to 0.05-0.15M KCl, while C. punctata had shown a different response at these molarities. Thus, the data favor a correlation between breathing modes and life style and the differences in pH or ionic strength sensitivities of ATPases. Unique profiles of peptide maps and the dispersal patterns of hydrophobic residues (cleavage sites of chymotrypsin) in MyHC of different muscle types further reflect individuality of their evolutionary histories.

991 Noninvasive Ventilation in Children, Can we Predict its Failure?

Background and AimsNoninvasive ventilation (NIV) constitutes an alternative treatment for pediatric acute respiratory failure. However, tracheal intubation should not be delayed when considered necessary. Our main objective is to identify...

Human Parvovirus 4 in Nasal and Fecal Specimens from Children, Ghana

Nonparenteral transmission might contribute to human parvovirus 4 (PARV4) infections in sub-Saharan Africa. PARV4 DNA was detected in 8 (0.83%) of 961 nasal samples and 5 (0.53%) of 943 fecal samples from 1,904 children in Ghana. Virus concentrations ≤6–7 log10 copies/mL suggest respiratory or fecal–oral modes of PARV4 transmission.

Live-bearing manta ray: how the embryo acquires oxygen without placenta and umbilical cord

We conducted an ultrasonographic experiment on a pregnant manta ray, Manta alfredi (Chondrichthyes, Batoidea). This study showed how the embryo of the live-bearing elasmobranchs respires in the body of the female. In the embryonic stage, the manta ray embryo takes in uterine fluid by buccal-pumping. After birth, the manta ray shifts its respiratory mode from buccal-pumping to ram-ventilation. The rapid reduction of the spiracle size in the young manta ray may reflect this shift of respiratory mode. Unlike mammals or some carcharhinid sharks that acquire oxygen through a placenta and umbilical cord, the manta ray embryo does not have a direct connection with the mother. Thus, the manta ray embryo obtains oxygen by buccal-pumping of the uterine fluid, in the same way that the embryos of egg-laying species obtain oxygen from the water in the egg case. This finding extends our understanding of the diversity of embryonic respiratory systems in live-bearing vertebrates.

SU-E-J-185: 4DCT Geometrical Eigenmode Model for Inter-Fraction Evaluation of Tumor Regression and Breathing Pattern Changes.

Evaluate the feasibility of using intra-fractional respiratory dominant eigenmodes of lung deformation as a method to track inter-fractional tumor regression and other physiological changes. Geometrical evaluation by dominant eigenmodes during free-breathing may be implemented as an IGART tool for assessing inter-fractional non-respiratory anatomical variation. Intra-fractional deformable image registration (DIR) is performed on 4DCT scans of lung cancer patients. Principal component analysis is conducted on a set of 10 deformation vector fields for each patient both with and without a lung mask. Leave-one-out cross-validation (LOOCV) is used to assess intra-fractional modeling error among a subset of respiratory phases. The first two dominant eigenmodes of PCA are compared across patients in axial, sagittal, and coronal slices. Eigenvalues between the first and second dominant respiratory modes decay by a factor of ten for all patients. Intra-fractional LOOCV maximum error is on the order of 1mm inside the lung and 4-6mm for the whole thorax for all patients using the first two dominant eigenmodes. Eigenvalue decay is fastest for patients where diaphragm motion is relatively larger in magnitude. The first two eigenmodes generally demonstrate a strong but smooth superior-inferior motion component with a lesser lateral and anterior-posterior component, while subsequent less dominant eigenmodes produce more random directional eigenvector fields. The two first principal components are consistent amongst patients. Inter-fractional eigenmode comparison may provide a means to track tumor regression and breathing pattern or physiological changes. We expect that patients with more dominant diaphragmatic respiration will allow for more delineated eigenmode classification. Clear dominant eigenmode delineation may allow subsequent less dominant eigenmodes to be inter-fractionally compared as a means to evaluate and compensate for tumor regression.

Submersion respiration in small diving beetles (Dytiscidae)

Some small diving beetles can survive submerged through weeks and months, because they can extract oxygen, dissolved in the water, through respiratory pores in their integument. An air flux from the outside to the inside through the respiratory pores has been demonstrated. All diving beetles capable of such pore respiration are small, but not all small diving beetles have pore respiration. With increasing size, more and more of the surface must be covered by respiratory pores to meet the increasing demand of oxygen. In running water species the pore-respiration mode is regarded as an adaptation to life in current exposed substrates, thus they avoid the risk of being swept away during frequent surface visits. In stagnant water species the pore respiration mode reduces the risk of falling victim to pelagic predators. The submersion tolerant species can switch to surface respiration, e.g. during low oxygen content. The pore respiratory mechanism is believed to be a specialised plastron. The oxygen flux through the scattered, small respiratory pore area may be enhanced by a functional thinning of the boundary layer.

Posturo-respiratory synchronization: Effects of aging and stroke

Spontaneous respiration influences the body's center-of-mass when standing. We contend that the healthy postural control system actively adapts to respiration, thereby minimizing its effect on postural sway. We therefore examined the interaction between respiration and postural sway, as measured by center-of-pressure (COP) oscillations, and quantified the extent to which this interaction resulted in “posturo-respiratory synchronization.” We hypothesized that synchronization would be stronger in elderly subjects and those with stroke, and when standing with eyes closed as compared to open, due to alterations in the physiologic mechanisms that normally regulate postural sway. Twenty-five subjects with chronic hemispheric infarction and 38 controls (50–80 years) stood on a force platform for 3min with eyes-open and 3min with eyes-closed. Respiratory flow and COP dynamics were simultaneously recorded. The dominant oscillatory mode of respiration and the corresponding oscillatory modes of anterioposterior and mediolateral COP dynamics were extracted using ensemble empirical mode decomposition. The strength of posturo-respiratory synchronization was quantified from the regularity of instantaneous phase shifts between extracted respiratory and COP oscillations. Significant posturo-respiratory synchronization was only present in the anterioposterior direction. The strength of synchronization increased with age (p<0.01). Closing the eyes increased synchronization strength in both groups (p=0.01), but more so in stroke patients (p=0.01). These observations suggest that a control system actively regulates the effects of respiration on sagittal-plane postural sway, particularly during eyes-open standing. As evidenced by increased posturo-respiratory synchronization with advanced age and central lesion, this novel metric may be used as a clinical marker of altered postural control.

Temporal and Spatial Profiling of Internode Elongation-Associated Protein Expression in Rapidly Growing Culms of Bamboo

In natural conditions, culms of developing Moso bamboo, Phyllostachys heterocycla var. pubescens, reach their final height of more than ten meters within a short period of two to four months. To study this phenomenon, bamboo culm material collected from different developmental stages and internodes was analyzed. Histological observations indicated that the development of culm was dominated by cell division in the initial stages and by cell elongation in the middle and late stages. Development, maturation, and aging in different regions of the culm were studied systematically from the basal to the top internode. The four major endogenous hormones, indole acetic acid, gibberellic acid, zeatin riboside, and abscisic acid appeared to strongly influence the cell elongation phase. A total of 258 spots were differentially expressed in culm development. Of these, 213 spots were identified by MALDI-TOF/TOF MS and were involved in many physiological and metabolic processes including carbohydrate metabolism, cell division, cell expansion, protein synthesis, amino acid metabolism and redox homeostasis. These proteins with different expression patterns constructed an ingenious network to regulate the culm development. Developmental stage-specific and internode-specific protein expression patterns were identified. Protein abundance was regulated temporally and to some extent spatially, and the sequential development from base to apex of bamboo culm was implemented by temporal and spatial expression of enzymes. Results indicate that during development energy was mainly derived from sucrose degradation, as photosynthetic capacity was poor. The regulation of anaerobic and aerobic modes of respiration appeared to play an important role in energy generation. This is the first report on proteomic profiling in bamboo and helps in understanding the regulatory processes in developing culms.

Airway Growth and Development: A Computerized 3-Dimensional Analysis

The present study was undertaken to investigate the changes in the normal upper airway during growth and development using 3-dimensional computer analysis from cone-beam computed tomography (CBCT) data to provide a normative reference. The airway size and respiratory mode are known to have a relationship to facial morphology and the development of a malocclusion. The use of CBCT, 3-dimensional imaging, and automated computer analysis in treatment planning allows the upper airway to be precisely evaluated. In the present study, we evaluated the growth of the airway using 3-dimensional analysis and CBCT data from age 6 through old age, in 1300 normal individuals. The airway size and length increase until age 20 at which time a variable period of stability occurs. Next, the airway at first decreases slowly in size and then, after age 40, more rapidly. Normative data are provided in the present study for age groups from 6 to 60 years in relation to the airway total volume, smallest cross-sectional area and vertical length of the airway. This 3-dimensional data of the upper airway will provide a normative reference as an aid in the early understanding of respiration and dentofacial anatomy, which will help in early treatment planning.

Hypercapnia attenuates inspiratory amplitude and expiratory time responsiveness to hypoxia in vagotomized and vagal-intact rats

A negative influence of central chemosensitivity on peripheral chemoreflex response has been demonstrated recently in a decerebrate-vagotomized rat preparation in situ with separate carotid body and brainstem perfusions. Here, we report similar negative influences of hypercapnia on the hypoxic respiratory response in anesthetized, spontaneously breathing rats before and after vagotomy and anesthetized, artificially ventilated rats after vagotomy. Baseline breathing patterns and responsiveness to hypercapnia and hypoxia varied widely between the three respiratory modes. Despite this, the responses in inspiratory amplitude and expiratory duration (and hence respiratory frequency and neural ventilation) to hypoxia varied inversely with the background CO2 level in all three groups. Results demonstrate a hypoadditive hypercapnic-hypoxic interaction in vivo that resembles the hypoadditive central-peripheral chemoreceptor interaction in situ for these respiratory variables in the rat, regardless of differences in vagal feedback, body temperature and ventilation method. These observations stand in contrast to previous reports of hyperadditive peripheral-central chemoreceptor interaction.

Uptake and depuration of pharmaceuticals in aquatic invertebrates

The uptake and depuration of a range of pharmaceuticals in the freshwater shrimp (Gammarus pulex) and the water boatman (Notonecta glauca) was studied. For one compound, studies were also done using the freshwater snail Planobarius corneus. In G. pulex, bioconcentration factors (BCFs) ranged from 4.6 to 185,900 and increased in the order moclobemide < 5-fluoruracil < carbamazepine < diazepam < carvedilol < fluoxetine. In N. glauca BCFs ranged from 0.1 to 1.6 and increased in the order 5-fluorouracil < carbamazepine < moclobemide < diazepam < fluoxetine < carvedilol. For P. corneus, the BCF for carvedilol was 57.3. The differences in degree of uptake across the three organisms may be due to differences in mode of respiration, behaviour and the pH of the test system. BCFs of the pharmaceuticals for each organism were correlated to the pH-corrected liposome–water partition coefficient of the pharmaceuticals.

The effect of mouth breathing on dentofacial morphology of growing child

The oral mode of respiration cause postural adaptations of structures in the head and neck region producing the effect on the positional relationship of the jaws. The aim of this study is to verify the skeletal relationship of mouth and nose breathing child. A cross sectional study was performed to assess the association of changed mode of respiration with dentofacial growth. One hundred children among which 54 were mouth breathers and 46 were nasal breathers of 6-12 years of age were submitted to clinical examination and cephalometric radiographical analysis. Statistical analysis : Chi-square test for proportions and independent sample's "t" test for parametric data is used. The mean values of N-Me (P<0.001) ANS-Me (P<0.001) and SN-GoGn (P<0.001) for mouth breathers is significantly higher. ArGo-GoMe (P=0.003) and (P<0.011) for 6-9 and 9-12 years age group, respectively, were significantly low in nasal breathers group. Changed mode of respiration was associated with increased facial height, mandibular plane angle and gonial angle.

Comparing Usefulness of Humidified High-Flow Nasal Cannula (HHFNC) and Nasal Continuous Positive Airway Pressure (NCPAP) for Neonatal Respiratory Diseases in Preterm Infants

Background and Aim: HHFNC is a widely used respiratory supportive mode for premature infants because of its relatively ease use and good compliance of infants as an alternative of nCPAP in many NICU. The aim of this study is to assess the clinical effectiveness and safety of a new HHFNC device (RT329 Infant Oxygen Delivery System) compared to nCPAP for neonatal respiratory diseases in preterm infants. Methods: Preterm infants who need respiratory support due to neonatal respiratory disease were supplied by HHFNC (n=35) or nCPAP (n=35). Primary outcomes included the rate of weaning and the rate of failure defined as intubation with mechanical ventilator care within 72 hour. Other outcomes included the duration of these respiratory supports, the improvement of vital signs (heart rate and respiratory rate), FiO2 needed for respiratory stabilization and the rate of complications (localized infection and necrosis, air leak syndrome, etc) after HHFNC or nCPAP. Results: There were no significant differences in demographics of patients. 65.7% (23/35) infants in HHFNC group weaned within 72 hours as compared with 74.3% (26/35) infants in nCPAP group (P=0.438 ). 20% (7/35) infants in HHFNC group were intubated compared with 17.1% (6/35) infants in nCPAP group (P=0.603). There were no significant differences in the duration of these respiratory supports and other outcomes. Conclusions: This study indicates that HHFNC may be used as an effective and safe alternative of nNCPAP in the preterm infants. But well-designed randomized study is necessary for clinical

Respiração bucal e anteriorização da cabeça: efeitos na biomecânica respiratória e na capacidade de exercício em crianças

OBJETIVO: Avaliar a tolerância ao exercício submáximo e a força muscular respiratória em relação à anteriorização da cabeça (AC) e ao tipo respiratório em crianças com respiração bucal (RB) ou nasal (RN). MÉTODOS: Estudo analítico transversal com um grupo controle no qual foram incluídas crianças de 8 a 12 anos com diagnóstico clínico otorrinolaringológico de RB, recrutadas do Ambulatório do Respirador Bucal do Hospital de Clínicas da Universidade Estadual de Campinas, Campinas (SP), entre outubro de 2010 e janeiro de 2011. Os critérios de exclusão foram obesidade, asma, doenças respiratórias crônicas, cardiopatias e distúrbios neurológicos ou ortopédicos. Todos os participantes foram submetidos a avaliação postural, teste de caminhada de seis minutos (TC6) e determinação de PImáx e PEmáx. RESULTADOS: Das 92 crianças do estudo, 30 tinham RB e 62 tinham RN. No grupo RB, não houve diferenças nas médias de PImáx, PEmáx e distância percorrida pelo TC6 (DTC6) entre o grupo com AC classificada como grave ou moderada e aquele com AC normal (p = 0,622; p = 0,957; e p = 0,079, respectivamente). No grupo RN, as médias de PImáx e PEmáx foram maiores no grupo com AC moderada do que naquele com AC normal (p = 0,003 e p = 0,004, respectivamente). Os valores de PImáx, PEmáx e DTC6 foram menores no grupo RB do que no grupo RN. A presença de AC moderada determinou maiores valores de PImáx e PEmáx. CONCLUSÕES: A RB afetou negativamente a biomecânica respiratória e a capacidade de exercício. A presença de AC moderada atuou como um mecanismo de compensação para uma melhor função da musculatura respiratória.

Influence of the respiratory mode and nonnutritive sucking habits in the palate dimensions

Aim: To verify the influence of the respiratory mode and nonnutritive sucking habits in the transverse and vertical dimensions of the palate. Methods: Seventy-seven children aged 7 to 12 years, were divided, according the diagnosis of the respiratory mode and the presence of prolonged nonnutritive sucking habits. Models of the upper dental arc were obtained of all children for evaluation of the measures of the palate in the region of the canines, first and second premolars and first molars. These measures were analyzed by the Student’s t-test and Analysis of Variance. Tukey’s test was used for the multiple comparisons. The significance level was set at p<0.05. Results: It was verified that the mouth-breathing children showed smaller width and higher depth at the more posterior region of the palate. The children with prolonged nonnutritive sucking habits presented narrower and deeper palate at the anterior region of the palate. The canine distance was smaller in children who present mouth breathing associated to nonnutritive sucking habits and the depth at the second premolar was higher in mouth-breathers associated or not to prolonged nonnutritive sucking habits. Conclusions: The results suggest that the respiratory mode and prolonged nonnutritive sucking habits influence in the transverse and vertical palate dimensions in the children evaluated in this study.