Respiratory Support Devices Research Articles

Pediatric Respiratory Support Technology and Practices: A Global Survey.

Objective: This global survey aimed to assess the current respiratory support capabilities for children with hypoxemia and respiratory failure in different economic settings. Methods: An online, anonymous survey of medical providers with experience in managing pediatric acute respiratory illness was distributed electronically to members of the World Federation of Pediatric Intensive and Critical Care Society, and other critical care websites for 3 months. Results: The survey was completed by 295 participants from 64 countries, including 28 High-Income (HIC) and 36 Low- and Middle-Income Countries (LMIC). Most respondents (≥84%) worked in urban tertiary care centers. For managing acute respiratory failure, endotracheal intubation with mechanical ventilation was the most commonly reported form of respiratory support (≥94% in LMIC and HIC). Continuous Positive Airway Pressure (CPAP) was the most commonly reported form of non-invasive positive pressure support (≥86% in LMIC and HIC). Bubble-CPAP was used by 36% HIC and 39% LMIC participants. ECMO for acute respiratory failure was reported by 45% of HIC participants, compared to 34% of LMIC. Oxygen, air, gas humidifiers, breathing circuits, patient interfaces, and oxygen saturation monitoring appear widely available. Reported ICU patient to health care provider ratios were higher in LMIC compared to HIC. The frequency of respiratory assessments was hourly in HIC, compared to every 2–4 h in LMIC. Conclusions: This survey indicates many apparent similarities in the presence of respiratory support systems in urban care centers globally, but system quality, quantity, and functionality were not established by this survey. LMIC ICUs appear to have higher patient to medical staff ratios, with decreased patient monitoring frequencies, suggesting patient safety should be a focus during the introduction of new respiratory support devices and practices.

Nitrous Oxide Inhalation Sedation Through a Nasal High-Flow System: The Possibility of a New Technique in Dental Sedation.

High-flow nasal cannula (HFNC) systems are increasingly used for patients with both acute and chronic respiratory failure because of the clinical effectiveness and patient comfort associated with their use. Recently, HFNC has been used not only as a respiratory support device, but also as a drug delivery system. HFNC is designed to administer heated and humidified inspiratory oxygen flows (100% relative humidity at 37°C). Therefore, HFNC can provide high flows (up to 60 L/min) without discomfort. Moreover, HFNC improves oxygenation by exerting physiologic effects such as (a) dead-space washout and (b) moderate positive airway pressure. These characteristics and physiologic effects of HFNC may permit administration of high-flow nitrous oxide sedation while ensuring patient comfort and adequate sedative effect.

Innovating affordable neonatal care equipment for use at scale.

The care of small and sick neonates requires biomedical technologies, such as devices that can keep babies warm (radiant warmers and incubators), resuscitate (self-inflating bags), track growth (weighing scales), treat jaundice (phototherapy units) and provide oxygen or respiratory support (hoods, continuous positive airway pressure (CPAP) devices and ventilators). Until the 1990s, most of these products were procured through import at a high cost and with little maintenance support. Emerging demand and an informal collaboration of neonatologists, engineers and entrepreneurs has led to the production of good quality equipment of several high-volume categories at affordable cost in India. Radiant warmers, resuscitation bags, phototherapy units, weighing scales and other devices manufactured by Indian small-scale companies have enabled an expansion of neonatal care in the country, particularly in district hospitals, medical college hospitals and subdistrict facilities in the public sector as a part of the National Rural Health Mission. Indian products have acquired international quality standards and are even exported to developed nations. This paper captures this story of innovation and entrepreneurship in neonatal care.

Early high flow nasal cannula therapy in bronchiolitis, a prospective randomised control trial (protocol): A Paediatric Acute Respiratory Intervention Study (PARIS).

BackgroundBronchiolitis imposes the largest health care burden on non-elective paediatric hospital admissions worldwide, with up to 15 % of cases requiring admission to intensive care. A number of previous studies have failed to show benefit of pharmaceutical treatment in respect to length of stay, reduction in PICU admission rates or intubation frequency. The early use of non-invasive respiratory support devices in less intensive scenarios to facilitate earlier respiratory support may have an impact on outcome by avoiding progression of the disease process. High Flow Nasal Cannula (HFNC) therapy has emerged as a new method to provide humidified air flow to deliver a non-invasive form of positive pressure support with titratable oxygen fraction. There is a lack of high-grade evidence on use of HFNC therapy in bronchiolitis.Methods/DesignProspective multi-centre randomised trial comparing standard treatment (standard subnasal oxygen) and High Flow Nasal Cannula therapy in infants with bronchiolitis admitted to 17 hospitals emergency departments and wards in Australia and New Zealand, including 12 non-tertiary regional/metropolitan and 5 tertiary centres. The primary outcome is treatment failure; defined as meeting three out of four pre-specified failure criteria requiring escalation of treatment or higher level of care; i) heart rate remains unchanged or increased compared to admission/enrolment observations, ii) respiratory rate remains unchanged or increased compared to admission/enrolment observations, iii) oxygen requirement in HFNC therapy arm exceeds FiO2 ≥ 40 % to maintain SpO2 ≥ 92 % (or ≥94 %) or oxygen requirement in standard subnasal oxygen therapy arm exceeds >2L/min to maintain SpO2 ≥ 92 % (or ≥94 %), and iv) hospital internal Early Warning Tool calls for medical review and escalation of care. Secondary outcomes include transfer to tertiary institution, admission to intensive care, length of stay, length of oxygen treatment, need for non-invasive/invasive ventilation, intubation, adverse events, and cost.DiscussionThis large multicenter randomised trial will allow the definitive assessment of the efficacy of HFNC therapy as compared to standard subnasal oxygen in the treatment of bronchiolitis.Trial registrationThe trial is registered with the Australian and New Zealand Clinical Trials Registry ACTRN12613000388718 (registered on 10 April 2013).

Sources d’exposition aux phtalates dans une unité de soins néonatals

There are growing concerns on long-term health consequences, notably on fertility rates, of plasticizers such as phthalates. While di(2-ethylhexyl)phthalate (DEHP) is currently used in several medical devices, newborns in the neonatal intensive care unit are both more exposed and more vulnerable to DEHP. The objectives of this study were to identify, count, and describe possible sources of DEHP in a neonatal care unit. Our method consisted in the listing and the inspection of the information on packaging, complemented by contact with manufacturers when necessary. According to the results, 6% of all products and 10% of plastic products contained some DEHP; 71% of these involved respiratory support devices. A vast majority of the items showed no information on the content of DEHP. Further research is needed, particularly to determine the effects of such an early exposure and to study and develop safer alternatives.

Nitric oxide delivery by neonatal noninvasive respiratory support devices.

Inhaled nitric oxide (INO) has been used with heated and humidified high-flow nasal cannula (HFNC), nasal CPAP and several forms of noninvasive ventilation (NIV). This study was designed to evaluate the delivered dose of INO, level of NO2 generation, and effect of net gas delivery (addition of INO to the ventilator circuit--gas removed for sampling) on lung pressure at different NO doses during noninvasive respiratory support. An infant lung model was supported with the different noninvasive modes during INO therapy. NO and NO2 were measured from within the patient circuit of the noninvasive devices and simulated neonatal trachea at several NO levels. Lung pressures were compared with and without INO and at several INO settings. Accuracy of NO delivery was determined to be within the stated accuracy by the manufacturer with nasal CPAP and NIV, but accuracy was compromised during HFNC. INO and NO2 measured by the INOmax DSIR (Ikaria, Hampton, New Jersey) did not consistently reflect the delivered dose of NO or formation of NO2 across all types of neonatal noninvasive respiratory support. Tracheal NO2 levels were <1.5 ppm with all forms of noninvasive support, except nasal intermittent mandatory ventilation at 40 ppm INO. Lung model mean airway pressures were mildly affected by gas sampling/delivery during combined INO therapy/HFNC at certain flows but remained stable with all other forms of noninvasive support. Clinicians cannot always assume that the set INO level results in a similar lung dose when using all forms of neonatal noninvasive support. Clinical decisions regarding ways to improve INO delivery may need to include changing settings or placing patients on a different form of noninvasive support. The NO2 level delivered to the patient could be greater than the value recorded by the INO delivery system.

Urgent Lung Transplantation National Program: The Italian Experience

IntroductionAn urgent lung transplantation national program in Italy was developed over the past three years. Indispensable conditions that were included in the program were invasive respiratory support and/or extracorporeal vascular device (DECAP excluded). The aim of this study was to test the effectiveness of the program. Materials and MethodsWe analyzed urgent lung requests received between 2009 and 2011 taking into account primary pathology, request outcome, average waiting time, and organ origin. Taking as reference the same period of time, we also examined the ordinary waiting list, waiting list mortality, and number of transplantations performed and we have compared them with another three-year period prior to the activation of the program. ResultsThe total number of urgent requests was 43. Primary pathologies with the highest incidence proportion were cystic fibrosis (40%) and idiopathic pulmonary fibrosis (26.6%). A total of 34 requests (79%) were successfully dealt with and 9 of them were suspended because of worsening conditions. The average waiting time was 17.9 days. During the same period of time 340 lung transplantations were performed and there were 499, 524, and 564 wait-listed patients in 2009, 2010, and 2011, respectively. The mortality rate was 21.3%. Over the previous three-year period 295 transplantations were performed and there were 457, 476, and 464 wait-listed patients in 2006, 2007, and 2008, respectively. Also the mortality rate was 25.3%. DiscussionUrgent lung transplantations can provide patients in an imminent life-threatening situation with adequate care without affecting the mortality rate of patients on the ordinary waiting list.

Modern cardio respiratory support devices: radiographic appearances

Purpose: 1. Demonstrate the appearances and appropriate positioning of various modern cardiac and respiratory support devices, with particular focus on ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) apparatus. 2. To educate the general radiologist reporting chest radiographs on the various modern specialized devices used for cardiac and respiratory support. 3. Highlight the importance of understanding device function and recognize complications associated with their use.

Introduction of bubble CPAP in a teaching hospital in Malawi

Continuous positive airway pressure (CPAP) is relatively inexpensive and can be easily taught; it therefore has the potential to be the optimal respiratory support device for neonates in developing countries. The possibility of implementing bubble CPAP in a teaching hospital with a large neonatology unit but very limited resources was investigated. A CPAP system was developed consisting of a compressor, oxygen concentrator, water bottle to control the pressure and binasal prongs. Neonates with birthweights between 1 and 2·5 kg with persistent respiratory distress 4 hours after birth were eligible for bubble CPAP. In the 7-week introduction period from 11 March until 27 April 2008, 11 neonates were treated with CPAP. Five of these neonates met the inclusion criteria and six neonates did not meet these criteria. Of the five neonates who received CPAP and met the inclusion criteria, three survived. The six infants who did not meet the inclusion criteria included three preterm infants with apnoea (all died), two with birthweights <1 kg (both died) and a firstborn twin (1.2 kg) who survived. No major complications of CPAP occurred. Bubble CPAP could be used independently by nurses after a short training period. Successful long-term implementation of CPAP depends on the availability of sufficient trained nursing staff.

Effective Gas Exchange in Paralyzed Juvenile Rabbits Using Simple, Inexpensive Respiratory Support Devices

We have developed two devices: a high-amplitude bubble continuous positive airway pressure (HAB-CPAP) and an inexpensive bubble intermittent mandatory ventilator (B-IMV) to test the hypotheses that simple, inexpensive devices can provide gas exchange similar to that of bubble CPAP (B-CPAP) and conventional mechanical ventilation (CMV). Twelve paralyzed juvenile rabbits were intubated, stabilized on CMV, and then switched to CPAP. On identical mean airway pressures (MAPs), animals were unable to maintain pulse oximeter oxygen saturation (SpO2) >80% on conventional B-CPAP, but all animals oxygenated well (97.3 ± 2.1%) on HAB-CPAP. In fact, arterial partial pressures of O2 (Pao2) were higher during HAB-CPAP than during CMV (p = 0.01). After repeated lung lavages, arterial partial pressures of CO2 (Paco2) were lower with B-IMV than with CMV (p < 0.0001), despite identical ventilator settings. In lavaged animals, when HAB-CPAP was compared with CMV at the same MAP and 100% O2, no differences were observed in Pao2, but Paco2 levels were higher with HAB-CPAP (70 ± 7 versus 50 ± 5 mm Hg; p < 0.05). Arterial blood pressures were not impaired by HAB-CPAP or B-IMV. The results confirm that simple inexpensive devices can provide respiratory support in the face of severe lung disease and could extend the use of respiratory support for preterm infants into severely resource-limited settings.

Monitoring Patient/Ventilator Interactions: Manufacturer's Perspective

The introduction of reduced and more powerful electronics has allowed the transition of medical equipment such as respiratory support devices from the hospital to the patient’s home environment. Even if this move could be beneficial for the patient, the clinician ends up in a delicate situation where little or no direct supervision is possible on the delivered treatment.Progress in technologies led to an improved handling of patient-device interaction: manufacturers are promoting new or improved ventilation modes or cycling techniques for better patient-ventilator coupling. Even though these ventilation modes have become more responsive to patient efforts, adversely they might lead to events such as false triggering, autotriggering, delayed triggering.In addition, manufacturers are developing tools to enhance the follow-up, remotely or offline, of the treatment by using embedded memory in the respiratory devices. This logging might be beneficial for the caregiver to review and document the treatment and tune the settings to the patient’s need and comfort. Also, remote telemedicine has been raised as a potential solution for many years without yet overall acceptance due to legal, technical and ethical problems.Benefits of new technologies in respiratory support devices give the technical foundation for the transition from hospital to home and reducing patient/ventilator asynchronies. Healthcare infrastructure has to follow this trend in terms of cost savings versus hospital stays.

Resolution of left lower lobe collapse postesophagectomy using the medivent rtx respirator, a novel noninvasive respiratory support system

THIS IS THE FIRST case report describing the use of a novel noninvasive respiratory support device, the RTX respirator (Medivent Ltd, London, UK) (Fig 1), for clearance of intractable secretions postesophagectomy. The patient had left lower lobe collapse and incipient respiratory failure. Routine postoperative physiotherapy techniques, combined with continuous positive airway pressure (CPAP) via a surgical tracheostomy, failed to clear retained sputum. The RTX respirator provided chest physiotherapy in the form of high-frequency oscillation interrupted by a “cough” phase to loosen and expel secretions (secretion clearance mode). These maneuvers allowed reinflation of the lobe, and the patient recovered. The mode of operation of the RTX respirator, and the properties of the device that may have contributed to the patient’s recovery, are discussed.

Expiratory Muscle Training Increases Pressure Support in High School Band Students

An experiment to increase expiratory muscle strength for instrumentalists, using a high-intensity, low-repetition expiratory training method, was conducted with 40 healthy high school band players. Subjects trained five days per week for 2 weeks using four sets of six training breaths for a total of 24 training breaths with a spring-loaded pressure relief valve that provided an adjustable threshold. The training valve pressure was set at 75% of the subject's measured maximum expiratory pressure (up to 80 cm H 2O). Results demonstrated that high-intensity, low-repetition expiratory exercises significantly increased expiratory pressure generating capacity in these subjects and the degree of the training effect was similar regardless of the instrument the band member played. The training effect occurred within 2 weeks of initiating expiratory muscle training. Thus, this simple method of expiratory-specific strength training is effective and efficient for increasing expiratory pressure support in high school band students and has possibilities of a respiratory support device for many high pressure generating purposes. The potential mechanisms of the training effect are discussed.

Nosocomial pulmonary infections

Despite major advances in intensive care therapies and techniques, nosocomial pneumonia remains a frequent complication in hospitalized patients. It has been shown that bacterial colonization of the oropharynx and tracheobronchial tree plays a major role in the pathogenesis of nosocomial pulmonary infection, that the bacterial sources of colonization may be both environmental and exogenous, and that the critical illness alters patient's defences against colonization and infection. Severity of underlying disease, presence of impaired airway reflexes and the use of respiratory support devices have been recognized as the most important risk factors for development of nosocomial pneumonia. New and promising prophylactic strategies and sophisticated techniques of microbiological diagnosis have recently been developed. However, many areas of controversy still exist, concerning the definitions and the classification of nosocomial pulmonary infections, the feasibility of certain diagnostic procedures and the choice of prophylactic protocols. Further advances in the diagnosis, the prevention, and the treatment of this complication require new and carefully designed studies in well-defined populations of critically ill patients.

Control of respiratory therapy by means of rheography (author's transl)

Rheography measures changes in electrical conductivity. In measurements taken at the thorax it was appeared that the changes in conductivity caused by breathing are superimposed by the changes caused by circulatory factors and exceed them in amplitude quite far. This makes the expansion of rheography for electrical respiration control possible. The changes in electrical conductivity are explained by inspiration into the alveoles, by the increase in the distance of the electrodes on thoracic expansion, and by the change in the intrathoracic blood volume. When using respiratory therapy the physiotherapist must pay great attention how the patient reacts to respiratory therapy and whether he is adapted correctly to the mechanical respiratory support devices. The method of "rheospirography" was tested as to whether it allows an objective, direct evaluation of the interplay between respiratory therapy and patient. The method appears to be able to control respiratory therapeutic measures as it allows an evaluation of the respiratory type, the regional ventilation, and the adaption of the patient to the device.

Control, monitor and alarm system for clinical application of a membrane oxygenator

Membrane oxygenators, now commercially available, are undergoing clinical trials as long-term (days) respiratory support devices for patients in potentially reversible respiratory failure. However, these devices must be used in an integrated system of controls, monitors and alarms if they are to be reliable and easy to operate in the clinical environment. This paper describes such a system. The tubing circuits for blood and for oxygen are described first. Next, details of the blood pump controls are presented. The system features servo control of pump speed to match blood inflow, and deactivation of the pump in the case of excessive output pressure. Gas circuit controls are described which allow the independent adjustment of both oxygen flow through the gas phase of the membrane lung and oxygen pressure developed at the inlet gas port. Audible alarms are provided for low blood inflow to the system, excessive blood outflow pressure, changes in oxygen flow and failure of the electric power supply to the system. In addition to pressure and flow monitors in the blood and gas circuits, blood oxygen saturation is continuously monitored at both input and output of the system. The membrane oxygenator system has proved to be reliable and easy to operate in both animal and human long-term perfusions.