Chest Wall Motion Research Articles

Difference between planned and delivered radiotherapy dose to the internal mammary nodes in high-risk breast cancer patients.

Chest wall movement during radiotherapy can impact the delivered dose to the internal mammary nodes (IMN) in high-risk breast cancer patients. Using portal imaging and dose reconstruction we aimed to examine the delivered IMN dose coverage. Cine MV images were recorded for 39 breast cancer patients treated with daily image-guided radiotherapy (IGRT) in deep-inspiration breath-hold (DIBH). On the final frame of each cine MV recording the chest wall was matched with the Digitally Reconstructed Radiograph (DRR) from the treatment plan. The geometrical chest wall error was determined in the imager-plane perpendicular to the cranio-caudal direction, rounded to integer millimeters, and binned. For each 1mm bin, an isocenter-shifted treatment plan was recalculated assuming that the projected error observed in the cine MV image was caused by anterior-posterior chest wall movement in the IMN region. A weighted plan sum yielded the IMN clinical target volume receiving at least 90% dose (V90_CTVn_IMN). The mean number of cine MV observations per patient was 36 (range 26-55). Most patients (67%) had on average a posterior chest wall position at treatment compared to planned. This translated into a change in the delivered median V90_CTVn_IMN of -0.7% (range, -11.9-2.9%; p<0.001). The V90_CTVn_IMN reduction wasgreater than9% in three patients. No clinically relevant differences were found for the mean lung dose or mean heart dose. Using cine MV images, we found that the delivered V90_CTVn_IMN was significantly lower than planned. In 8% of the patients, the V90_CTVn_IMN reduction exceeded 9%.

Pi-ViMo: Physiology-inspired Robust Vital Sign Monitoring using mmWave Radars

Continuous monitoring of human vital signs using non-contact mmWave radars is attractive due to their ability to penetrate garments and operate under different lighting conditions. Unfortunately, most prior research requires subjects to stay at a fixed distance from radar sensors and to remain still during monitoring. These restrictions limit the applications of radar vital sign monitoring in real life scenarios. In this article, we address these limitations and present Pi-ViMo, a non-contact P hysiology- i nspired Robust Vi tal Sign Mo nitoring system, using mmWave radars. We first derive a multi-scattering point model for the human body, and introduce a coherent combining of multiple scatterings to enhance the quality of estimated chest-wall movements. It enables vital sign estimations of subjects at any location in a radar’s field of view (FoV). We then propose a template matching method to extract human vital signs by adopting physical models of respiration and cardiac activities. The proposed method is capable to separate respiration and heartbeat in the presence of micro-level random body movements (RBM) when a subject is at any location within the field of view of a radar. Experiments in a radar testbed show average respiration rate errors of 6% and heart rate errors of 11.9% for the stationary subjects, and average errors of 13.5% for respiration rate and 13.6% for heart rate for subjects under different RBMs.

MmRH: Noncontact Vital Sign Detection With an FMCW mm-Wave Radar

Vital signs, such as respiration rate (RR) and heart rate (HR), are essential for human health status assessment. The radar could detect RR and HR in a noncontact manner by sensing the repetitive chest wall movement caused by cardiopulmonary activity, which is attractive due to the more comfortable experience and better privacy protection. However, as the chest wall displacement caused by heartbeat is much smaller than that caused by respiration, the weak heartbeat component may be easily overwhelmed by respiration harmonics, noise, and clutter, making it difficult to achieve accurate and reliable HR detection. In order to tackle this challenge, in this article, we design mmRH, a system that can accurately estimate RR as well as HR using a frequency-modulated continuous-wave (FMCW) millimeter-wave (mm-wave) radar, which consists of four functional modules. In the vital sign signal extraction module, the range bin corresponding to the body part with strong vital signs is determined to extract the vital sign signal, eliminating the clutter interference. The differential enhancement module is proposed to enhance the heartbeat component by the first-order temporal difference, reducing the impacts of respiration harmonics and noise on HR estimation. In the signal decomposition module, the respiration and heartbeat signals are separated via wavelet packet decomposition (WPD) to further suppress respiration harmonics and high-frequency noise of the heartbeat signal. In the vital sign rate reconstruction module, the sparse spectrum reconstruction (SSR) of vital sign rates is mapped to an adaptive filter and zero attracting sign exponentially forgetting least mean square (ZA-SEFLMS) algorithm is proposed to achieve high-resolution sparse spectrum for accurate and reliable RR and HR estimation. The effects of different settings, including the distance between the human subject and the radar, the sensor position, and the user heterogeneity, are investigated by extensive experiments. The results indicate that the designed mmRH could effectively suppress the respiration harmonics, noise, and clutter interference, and bring a significant improvement in RR and HR detection accuracy compared with existing methods.

Design and Testing of a Smart Facemask for Respiratory Monitoring during Cycling Exercise

Given the importance of respiratory frequency (fR) as a valid marker of physical effort, there is a growing interest in developing wearable devices measuring fR in applied exercise settings. Biosensors measuring chest wall movements are attracting attention as they can be integrated into textiles, but their susceptibility to motion artefacts may limit their use in some sporting activities. Hence, there is a need to exploit sensors with signals minimally affected by motion artefacts. We present the design and testing of a smart facemask embedding a temperature biosensor for fR monitoring during cycling exercise. After laboratory bench tests, the proposed solution was tested on cyclists during a ramp incremental frequency test (RIFT) and high-intensity interval training (HIIT), both indoors and outdoors. A reference flowmeter was used to validate the fR extracted from the temperature respiratory signal. The smart facemask showed good performance, both at a breath-by-breath level (MAPE = 2.56% and 1.64% during RIFT and HIIT, respectively) and on 30 s average fR values (MAPE = 0.37% and 0.23% during RIFT and HIIT, respectively). Both accuracy and precision (MOD ± LOAs) were generally superior to those of other devices validated during exercise. These findings have important implications for exercise testing and management in different populations.

BRAVEHeart: a randomised trial comparing the accuracy of Breathe Well and RPM for deep inspiration breath hold breast cancer radiotherapy

BackgroundDeep inspiration breath hold (DIBH) reduces radiotherapy cardiac dose for left-sided breast cancer patients. The primary aim of the BRAVEHeart (Breast Radiotherapy Audio Visual Enhancement for sparing the Heart) trial is to assess the accuracy and usability of a novel device, Breathe Well, for DIBH guidance for left-sided breast cancer patients. Breathe Well will be compared to an adapted widely available monitoring system, the Real-time Position Management system (RPM).MethodsBRAVEHeart is a single institution prospective randomised trial of two DIBH devices. BRAVEHeart will assess the DIBH accuracy for Breathe Well and RPM during left-sided breast cancer radiotherapy. After informed consent has been obtained, 40 patients will be randomised into two equal groups, the experimental arm (Breathe Well) and the control arm (RPM with in-house modification of an added patient screen). The primary hypothesis of BRAVEHeart is that the accuracy of Breathe Well in maintaining the position of the chest during DIBH is superior to the RPM system. Accuracy will be measured by comparing chest wall motion extracted from images acquired of the treatment field during breast radiotherapy for patients treated using the Breathe Well system and those using the RPM system.DiscussionThe Breathe Well device uses a depth camera to monitor the chest surface while the RPM system monitors a block on the patient’s abdomen. The hypothesis of this trial is that the chest surface is a better surrogate for the internal chest wall motion used as a measure of treatment accuracy. The Breathe Well device aims to deliver an easy-to-use implementation of surface monitoring. The findings from the study will help inform the technology choice for other centres performing DIBH.Trial registrationClinicalTrials.govNCT02881203. Registered on 26 August 2016.

Frequency Comb-Based Ground-Penetrating Bioradar: System Implementation and Signal Processing.

Radars can be used as sensors to detect the breathing of victims trapped under layers of building materials in catastrophes like earthquakes or gas explosions. In this contribution, we present the implementation of a novel frequency comb continuous wave (FCCW) bioradar module using a commercial software-defined radio (SDR). The FCCW radar transmits multiple equally spaced frequency components simultaneously. The data acquisition of the received combs is frequency domain-based. Hence, it does not require synchronization between the transmit and receive channels, as time domain-based broadband radars, such as ultra wideband (UWB) pulse radar and frequency-modulated CW (FMCW) radar, do. Since a frequency comb has an instantaneous wide bandwidth, the effective scan rate is much higher than that of a step frequency CW (SFCW) radar. This FCCW radar is particularly suitable for small motion detection. Using inverse fast Fourier transform (IFFT), we can decompose the received frequency comb into different ranges and remove ghost signals and interference of further range intervals. The frequency comb we use in this report has a bandwidth of only 60 MHz, resulting in a range resolution of up to 2.5 m, much larger than respiration-induced chest wall motions. However, we demonstrate that in the centimeter range, motions can be detected and evaluated by processing the received comb signals. We want to integrate the bioradar into an unmanned aircraft system for fast and safe search and rescue operations. As a trade-off between ground penetrability and the size and weight of the antenna and the radar module, we use 1.3 GHz as the center frequency. Field measurements show that the proposed FCCW bioradar can detect an alive person through different nonmetallic building materials.

Usefulness of supplemental parasternal block for sternal keloid excision under general anesthesia in a child status post multiple cardiac surgeries

Sir A 12-year-old boy weighing 60 kg, with history of tricuspid atresia, had undergone right modified Blalock–Thomas–Taussig shunt, and patent ductus arteriosus ligation on day 1 of life. One year later he underwent bidirectional Glenn shunt, and extra cardiac Fontan surgery was done at 6 years. He presented now with a thick keloid in the midline sternotomy scar for keloid excision. Current screening echo showed tricuspid atresia, normally related great arteries with normal ventricular flow and unobstructed Glenn and Fontan flow profiles. Intravenous midazolam 1 mg, fentanyl 100 mcg and ketamin 60 mg were given and incremental bolus of propofol 10 mg (total 20 mg) was given till loss of response to verbal commands and relaxation of jaw. Airway was then secured with size 3 proseal laryngeal mask airway (PLMA) and correct placement was ensured with regular endtidal carbon dioxide (ETCO2) waveforms. Parasternal block was then given under ultrasound guidance at third and fifth intercostal spaces 2 cm lateral to midline bilaterally. Spread of injected solution causing separation of pectoralis major muscle from the rib and external intercostal muscle confirmed deposition of drug in the correct plane (Fig. 1). Ten milliliter of 0.25% bupivacaine was injected at each site.Figure 1: Superficial parasternal-intercostal plane block.Anesthesia was maintained with sevoflurane (1.5–2%) in air oxygen mixture under spontaneous ventilation. Intraoperatively patient remained stable with heart rate 86-98/min, systolic blood pressure 90–100 mmHg, oxygen saturation 96–98% and ETCO2 32-40 mmHg and had received 500 ml of Ringer lactate. At the end of surgery, which lasted for 2 h, PLMA was removed when patient was awake. He had good postoperative analgesia. Anesthetic goals in a child post-Fontan surgery include adequate hydration, avoidance of hypoxia, hypercabia, and acidosis and preservation of spontaneous ventilation whenever possible. If general anesthesia is mandated, low inspiratory pressures and minimal positive end expiratory pressures are to be used [1,2]. Sternotomy produces considerable pain which increases with chest wall movement and reduces pulmonary function with higher risk of development of postoperative hypoxia, atelectasis, and pneumonia [3]. Parasternal block is commonly advocated to provide supplemental anaesthesia intraoperatively and for postoperative analgesia following median sternotomy, breast surgery and cardioverter-defibrillator implantation [4,5]. The nerve targeted is the anterior branches of intercostal nerves which enters intercostal and pectoralis major muscles and innervates the antero-medial region of chest wall. Local anesthetic is injected deep to pectoralis major muscle and superficial to intercostal muscles or between internal thoracic muscle and transverses thoracis muscle. Therefore, these blocks are essentially described as superficial or deep parasternal-intercostal plane blocks, depending on where the target nerves are blocked. The anatomical injection site differentiates these techniques though both techniques provide analgesia to the antero-medial chest wall [5]. Supplemental regional block helps to reduce dose requirement of anesthetic agents intraoperatively. Use of supplemental parasternal block enabled us to keep the child spontaneously breathing under general anaesthesia using PLMA with use of lesser doses of anesthetic agents, thereby minimising drug adverse effects which could be deleterious in the presence of cardiac diseases. It is concluded that supplemental parasternal block provides good intraoperative and postoperative analgesia following anterior midline chest wall surgeries.

Respiratory Function Assessment through Kinematic Analysis of Chest Wall Movements: Effects of Position and Gender.

The effect of position and gender on chest movements and respiratory volumes is controversial and investigated in only a few studies. This study aimed to investigate the effects of position and gender on the breathing pattern during four different positions in healthy individuals. In this cross-sectional study, twenty-eight (14 males, 14 females) healthy individuals participated aged 20-45 years. The optoelectronic plethysmography (OEP) method was used for the three-dimensional evaluation of chest wall motions and the compartmental analysis of the breathing pattern in supine, sitting, standing, and active straight leg raised (ASLR) positions. Volume changes in different parts of the chest wall were also measured. Position affected total and compartmental respiratory volumes in both genders. Respiratory volumes decreased in the supine position compared to sitting and standing. Total and abdominal respiratory volumes also decreased in females when comparing supine positions with the ASLR. A higher pulmonary rib cage contribution was identified in females, and males exhibited higher abdominal rib cage volume compared with females. The breathing pattern was affected by position and gender, and the respiratory volumes increased in more upright positions, perhaps due to a greater gravitational load. The ASLR decreases the respiratory volume, which is probably due to increased postural demand.

Thoracic and abdominal breathing volumes in various body positions

Optoelectronic plethysmography, a non-invasive motion capture technique, calculates the tidal volume and tracks chest wall motions. This study used a motion capture system and a compression shirt with markers embedded in anatomical landmarks as optoelectronic plethysmograph to measure trunk movement in three different positions (standing, sitting, and lying). The recorded data were then processed to compare the contribution of thoracic and abdominal breathing during these three positions. The study showed that abdominal breathing predominates at low tidal volumes and when lying supine. The development of Smart-Shirts for breath analysis can be supported by the outcomes modeling approaches that could be improved.

Analysis of the Chest Wall Reconstruction Methods after Malignant Tumor Resection.

Background The chest wall defects can be caused by various reasons. In the case of malignant tumor resection of the chest wall, it is essential to reconstruct the chest wall to cover the vital tissue and restore the pulmonary function with prevention of paradoxical motion. With our experience, we analyzed and evaluated the results and complications of the chest wall reconstructions followed by malignant tumor resection. Methods From 2013 to 2022, we reviewed a medical record of patients who received chest reconstruction due to chest wall malignant tumor resection. The following data were retrieved: patients' demographic data, tumor type, type of operation, method of chest wall reconstruction of the soft and skeletal tissue and complications. Results There were seven males and six female patients. The causes of reconstruction were 12 primary tumors and one metastatic carcinoma. The pathological types were seven sarcomas, three invasive breast carcinoma, and three squamous cell carcinomas. The skeletal reconstruction was performed in six patients. The series of the flap were eight pedicled latissimus dorsi (LD) myocutaneous flaps, two pectoralis major myocutaneous flap, two vertical rectus abdominis myocutaneous free flap, and one LD free flap. Among all the cases, only one staged reconstruction and successful reconstruction without flail chest. Most of the complications were atelectasis. Conclusion In the case of accompanying multiple ribs and sternal defect, skeletal reconstruction would need skeletal reconstruction to prevent paradoxical chest wall motion. The flap for soft tissue defect be selected according to defect size and location of chest wall. With our experience, we recommend the reconstruction algorithm for chest wall defect due to malignant tumor resection.

Reference Values of Chest Expansion among Healthy Children: A Cross-sectional Study

Abstract Background and Objective: Examination of the chest wall movement during breathing provides valuable insight into the function of a person’s respiratory system. Chest mobility and lung function may be altered due to growth, body composition, and respiratory disease. Preliminary baseline values for measuring chest expansion were obtained for healthy adult Indians. However, because the rib configuration of children differs from that of an adult, reference values for children need to be established. Materials and Methods: In the present study, chest expansion was measured at three levels – second rib, fourth rib, and xiphisternum (R2, R4, and xiphisternum level which was marked at the lower end of the body of the sternum) – in 720 children aged 5–12 years using a nonstretchable measuring tape. The difference between chest circumference at maximum expiration and maximum inspiration was recorded as the value of chest expansion. Out of three, one best value and not an average value was considered a chest expansion measurement at each level. Results: Three subgroups were made: 5–7 years, 8–10 years, and 11–12 years. Results were documented and presented as mean and standard deviation for each subgroup. The reference values for chest expansion among healthy children in the age group of 5–12 years are 2.5 cm–3.2 cm at the R2 level, 3.1 cm–3.7 cm at the R4 level, and 3.8 cm–4.1 cm at the xiphisternum level. Conclusions: The chest expansion for different age groups among healthy children was different.

Characteristics of Diaphragmatic and Chest Wall Motion in People with Normal Pulmonary Function: A Study with Free-Breathing Dynamic MRI.

We aimed to quantitatively study the characteristic of diaphragm and chest wall motion using free-breathing dynamic magnetic resonance imaging (D-MRI) in Chinese people with normal lung function. 74 male subjects (mean age, 37 ± 11 years old) were prospectively enrolled, and they underwent high-resolution CT(HRCT), pulmonary functional tests (PFTs), and D-MRI in the same day. D-MRI was acquired with a gradient-echo sequence during the quiet and deep breathing. The motion of the diaphragm and chest wall were respectively assessed by measuring thoracic anteroposterior diameter (AP), left-right diameter (LR), cranial-caudal diameter (CC), and thoracic area ratios between end-inspiration and end-expiration. The effect of age, body mass index (BMI), and smoking on respiratory muscle function was also analyzed. The mean ratio of right and left AP was greater than that of LR on three transversal planes during both quiet and deep breathing. The mean ratio at the anterior diaphragm (AND, Quiet: 1.04 ± 0.03; Deep: 1.15 ± 0.09) was weaker than that of the apex (vs. APD, Quiet: 1.08 ± 0.05, p &lt; 0.001; Deep: 1.29 ± 0.12, p &lt; 0.001) and posterior diaphragm (vs. POD, Quiet: 1.09 ± 0.04, p &lt; 0.001; Deep: 1.30 ± 0.12, p &lt; 0.001) both in quiet and deep breathing. Compared with non-smokers, the left AP and thoracic area ratios in smokers were significantly decreased (p &lt; 0.05). However, the ratios of AP, LR, CC, and thoracic area on each plane were similar among groups in different age and BMI. During both quiet and deep breathing, the chest wall motion is prominent in the anteroposterior direction. The motions of diaphragm apex and posterior diaphragm were more prominent than that of the anterior diaphragm. Smoking may affect the respiratory muscle mobility. Dynamic MRI can quantitatively evaluate the motion of respiratory muscles.

Detection of pneumothorax on ultrasound using artificial intelligence.

Ultrasound (US) for the detection of pneumothorax shows excellent sensitivity in the hands of skilled providers. Artificial intelligence may facilitate the movement of US for pneumothorax into the prehospital setting. The large amount of training data required for conventional neural network methodologies has limited their use in US so far. A limited training database was supplied by Defense Advanced Research Projects Agency of 30 patients, 15 cases with pneumothorax and 15 cases without. There were two US videos per patient, of which we were allowed to choose one to train on, so that a limited set of 30 videos were used. Images were annotated for ribs and pleural interface. The software performed anatomic reconstruction to identify the region of interest bounding the pleura. Three neural networks were created to analyze images on a pixel-by-pixel fashion with direct voting determining the outcome. Independent verification and validation was performed on a data set gathered by the Department of Defense. Anatomic reconstruction with the identification of ribs and pleura was able to be accomplished on all images. On independent verification and validation against the Department of Defense testing data, our program concurred with the SME 80% of the time and achieved a 86% sensitivity (18/21) for pneumothorax and a 75% specificity for the absence of pneumothorax (18/24). Some of the mistakes by our artificial intelligence can be explained by chest wall motion, hepatization of the underlying lung, or being equivocal cases. Using learning with limited labeling techniques, pneumothorax was identified on US with an accuracy of 80%. Several potential improvements are controlling for chest wall motion and the use of longer videos. Diagnostic Tests; Level III.

MRI-assessed diaphragmatic function can predict frequent acute exacerbation of COPD: a prospective observational study based on telehealth-based monitoring system

BackgroundAcute exacerbations of chronic obstructive pulmonary disease (AECOPD) have considerably high mortality and re-hospitalisation rate. Diaphragmatic dysfunction (DD) is common in COPD patients. However, whether diaphragmatic dysfunction is related to acute exacerbation is yet to be elucidated. This study aimed to evaluate the diaphragm function by magnetic resonance imaging (MRI) in COPD patients and assess whether the impact of DD may help predict AECOPD.Methods20 healthy adult volunteers and 80 COPD patients were enrolled. The diaphragms function parameters were accessed by MRI. Patients were guided to start self-management by the Telehealth-based monitoring system following the enrolment. Events of acute exacerbation of COPD were recorded by the system and confirmed by healthcare providers. Binary univariate and multivariate logistic regression analyses were performed to investigate the factors associated with the frequency of AECOPD. Receiver operating characteristic (ROC) curves were further used to assess the value of prediction indexes.ResultsFifty-nine COPD patients completed a one-year follow-up based on the Telehealth-based monitoring system. The clinical outcomes showed that the diaphragm function parameters at the end of maximal breathing were lower in the COPD group than in the healthy control group (P < 0.05). ANOVA showed significant differences among Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages for diaphragm function parameters, including chest wall motion, lung area, upper-lower diameter, and the diaphragm thickening fraction at the end of maximal breathing (P < 0.05). Moreover, significant differences in diaphragm function parameters were observed between patients with infrequent AECOPD (n = 28) and frequent AECOPD (n = 31) based on the frequency of AECOPD (P < 0.05). The diaphragm thickening fraction and the chest wall motion were associated with AECOPD after adjusting for age, sex, BMI, and lung functions, and the combination of predictions showed better accuracy in predicting the frequency of AECOPD.ConclusionsIn COPD patients, diaphragm function parameters correlate with the severity of airflow limitation. The diaphragm thickening fraction and the chest wall motion were associated with the frequency of AECOPD and can predict it.

Pectus excavatum in motion: dynamic evaluation using real-time MRI

ObjectivesThe breathing phase for the determination of thoracic indices in patients with pectus excavatum is not standardized. The aim of this study was to identify the best period for reliable assessments of morphologic indices by dynamic observations of the chest wall using real-time MRI.MethodsIn this prospective study, patients with pectus excavatum underwent morphologic evaluation by real-time MRI at 3 T between January 2020 and June 2021. The Haller index (HI), correction index (CI), modified asymmetry index (AI), and modified eccentricity index (EI) were determined during free, quiet, and forced breathing respectively. Breathing-related differences in the thoracic indices were analyzed with the Wilcoxon signed-rank test. Motion of the anterior chest wall was analyzed as well.ResultsA total of 56 patients (11 females and 45 males, median age 15.4 years, interquartile range 14.3–16.9) were included. In quiet expiration, the median HI in the cohort equaled 5.7 (4.5–7.2). The median absolute differences (Δ) in the thoracic indices between peak inspiration and peak expiration were ΔHI = 1.1 (0.7–1.6, p < .001), ΔCI = 4.8% (1.3–7.5%, p < .001), ΔAI = 3.0% (1.0–5.0%, p < .001), and ΔEI = 8.0% (3.0–14.0%, p < .05). The indices varied significantly during different inspiratory phases, but not during expiration (p > .05 each). Furthermore, the dynamic evaluation revealed three distinctive movement patterns of the funnel chest.ConclusionsReal-time MRI reveals patterns of chest wall motion and indicate that thoracic indices of pectus excavatum should be assessed in the end-expiratory phase of quiet expiration.Key Points• The thoracic indices in patients with pectus excavatum depend on the breathing phase.• Quiet expiration represents the best breathing phase for determining thoracic indices.• Real-time MRI can identify different chest wall motion patterns in pectus excavatum.

Anesthetic management using high-flow nasal cannula therapy during cardiac catheter examination of a neonate with hypoplastic left heart syndrome

BackgroundSedation during cardiac catheter examination in neonates with complex congenital heart disease is challenging, as even the slightest change in the circulatory or respiratory status can lead to hemodynamic collapse. Here, we report a case wherein we achieved adequate sedation with a high-flow nasal cannula (HFNC) for catheter examination in a neonate with a congenital cardiac anomaly.Case presentationAn 11-day-old boy with hypoplastic left heart syndrome was scheduled for a cardiac catheter examination prior to the Norwood procedure. He underwent bilateral pulmonary artery banding (PAB) on day 1 and was receiving dobutamine, milrinone, alprostadil, and dexmedetomidine in addition to air and nitrogen insufflation via HFNC, which was applied following extubation on day 3 and nitrogen therapy on day 6 owing to persistent pulmonary overcirculation symptoms (tachypnea and low arterial blood pressure) despite bilateral PAB. A catheter examination was performed on day 11 with careful monitoring of expired carbon dioxide and observation of chest wall motion. Adequate sedation was provided with supplemental midazolam and fentanyl along with HFNC without tracheal intubation.ConclusionsThe findings from this case suggest that HFNC is a safe and effective tool for oxygenation during cardiac catheter examination under sedation in neonates.

Investigating Stroke Effects on Respiratory Parameters Using a Wearable Device: A Pilot Study on Hemiplegic Patients.

Quantitatively assessing personal health status is gaining increasing attention due to the improvement of diagnostic technology and the increasing occurrence of chronic pathologies. Monitoring physiological parameters allows for retrieving a general overview of the personal health status. Respiratory activity can provide relevant information, especially when pathologies affect the muscles and organs involved in breathing. Among many technologies, wearables may represent a valid solution for continuous and remote monitoring of respiratory activity, thus reducing healthcare costs. The most popular wearables used in this arena are based on detecting the breathing-induced movement of the chest wall. Therefore, their use in patients with impaired chest wall motion and abnormal respiratory kinematics can be challenging, but literature is still in its infancy. This study investigates the performance of a custom wearable device for respiratory monitoring in post-stroke patients. We tested the device on six hemiplegic patients under different respiratory regimes. The estimated respiratory parameters (i.e., respiratory frequency and the timing of the respiratory phase) demonstrated good agreement with the ones provided by a gold standard device. The promising results of this pilot study encourage the exploitation of wearables on these patients that may strongly impact the treatment of chronic diseases, such as hemiplegia.

Quantitative Analysis by 3D Graphics of Thoraco-Abdominal Surface Shape and Breathing Motion

Chest wall motion can provide information on respiratory muscles' action and on critical vital signs, like respiration and cardiac activity. The chest wall is a structure with three compartments that are independent to each other and can move paradoxically according to the pathophysiology of the disease. Opto-electronic plethysmography (OEP) allows for non-invasively 3D tracking of body movements. We aimed to extend the characteristics of OEP analysis to local analyses of thoraco-abdominal surface geometry and kinematics during respiration. Starting from the OEP output file, the 3D markers’ coordinates were combined with a triangulation matrix. A smoothing procedure (an automatic and iterative interpolation process to increase the number of vertices from 93 to 548) was applied to allow for precise local analysis of the thoraco-abdominal surface. A series of measurements can be performed to characterize the geometry of the trunk and its three compartments, in terms of volumes, height, diameters, perimeters, and area. Some shape factors, such as surface-to-volume ratio or height-to-perimeter ratio, can be also computed. It was also possible to build the vector field associated with the breathing motion of all the vertices, in terms of magnitude and motion direction. The vector field data were analyzed and displayed through two graphic tools: a 3D heatmap, in which the magnitude of motion was associated to different colors, and a 3D arrow plot, that allowed us to visualize both the magnitude and the direction of motion with color-coded arrows. The methods were applied to 10 healthy subjects (5 females) and also applied to two cases: a pregnant woman at each trimester of gestation and a patient before and after a demolition thoracic surgery. The results proved to be coherent with the physiology of healthy subjects and the physiopathology of the cases. We developed a new non-invasive method for respiratory analysis that allowed for the creation of realistic 3D models of the local and global trunk surface during respiration. The proposed representation constituted a very intuitive method to visualize and compare thoraco-abdominal surface movements within and between subjects, therefore enforcing the potential clinical translational value of the method.

Radar Evaluation Setup for the Replication of Chest Wall Movement from Vital Signs.

In this paper we present a setup to generate micro movement which is analog to the chest wall micro movement from vital signs. The movement is produced by a loudspeaker powered by a function generator. Since it is difficult to isolate and reproduce effects in the context of vital signs measurements with the human body, this setup allows an easier development of radar post processing algorithms. In addition, some effects are difficult to measure with a human, for example heart diseases like cardiac arrhythmia. To evaluate the setup, we present reference measurements with a human. Also, we show the results of measurements with the setup made with three different radar systems, which use different center frequencies: 24 GHz, 60 GHz and 77 GHz. The setup is able to create absolutely smooth and exact movement which is linear to the applied voltage. This is important in order to simulate several effects in the heart and breathing movement.

Ventilation through a straw.

Transtracheal jet ventilation can be used for resuscitation of partial airway obstruction. A prerequisite for jet ventilation is that at least a minimum airway opening for gas escape must be secured. Therefore, another option should be considered in cases of complete airway obstruction. The following methods or devices has been used under cricothyrotomy using an intravenous cannula: 1) Ambu (bag valve mask) bagging, 2) Ventrain®, 3) Rapid-O2 oxygen insufflation device (Rapid-O2), and 4) jet ventilation using a dual lumen catheter. During Ambu bagging, extraordinarily high insufflation pressure is required to force oxygen through the cannula. When using a 12-G cannula, long and slow positive-pressure ventilations (10–12 breaths/min) are required, which makes it extremely difficult to compress the bag. Therefore, a 10-G or larger is recommended. Ventrain® is an expiratory assist device capable of forcibly expelling insufflated oxygen through a transtracheal cannula. It is recommended to adjust the inspiratory and expiratory times while observing the chest wall movements. Rapid-O2 is a rescue oxygenation device with adequate ventilation of less importance; therefore, the resulting hypercarbia is inevitable. A 14-G cannula is used. Lastly, jet ventilation using a dual-lumen catheter with a 16-G inflow lumen and 10-G outflow lumen was used to obtain both oxygenation and ventilation. However, the addition of the outer diameters of 16-G and 10-G results in an outer diameter of 5.1 mm, which is too large to puncture the cricothyroid membrane. In conclusion, Ventrain® is considered the most ideal device for use among the devices developed to date.