Active clinical trials for "Hypercapnia"

A comparative study which compares the end-tidal carbon dioxide and oxygen saturation levels of patients during endoscopy which have used either the new oral-nasal oxygenating device (TwinGuard), or a standard bite block plus nasal cannulae using an equivalent flow rate of oxygen.

Chronic respiratory insufficiency and COPD are the third leading cause of death worldwide. Patients decompensate at various stages of their disease and exhibit acute-on-chronic respiratory failure (ACRF), a frequent cause of ICU hospitalization for hypercapnic acute respiratory failure (ARF). Non-invasive ventilation (NIV) is the first line ventilatory treatment for hypercapnic ARF. It is applied intermittently, separated by periods of spontaneous breathing (SB) with standard oxygen (O2). Standard O2 has drawbacks that limit the benefit of intermittent NIV in hypercapnic ARF: limited gas flow which is well below the patient's inspiratory flow rate, limited capacity and efficiency of oxygenation with non-controlled FiO2 (risk of excessive oxygen and induced hypercapnia), and cold and dry gas leading to discomfort and under-humidification of the airways and tracheobronchial secretions. Benefits in terms of work of breathing and CO2 removal resulting from PEEP and pressure support applied during NIV periods could be rapidly lost during standard O2. Recently, use of high-flow heated and humidified nasal oxygen therapy (HFHO) has gained enthusiasm among intensivists to manage ARF. HFHO delivers high flows (up to 60L/min, that generate moderate PEEP) of heated and humidified oxygen at a controlled and adjustable FiO2 (21 to 100%) that rapidly improve respiratory distress symptoms, oxygenation, respiratory comfort and outcome of patients with hypoxemic ARF. These unique features of HFHO could overcome some of the drawbacks of standard O2 during SB periods in hypercapnic ARF. Indeed, PEEP effect, washout of nasopharyngeal dead-space limiting CO2 re-breathing and inspired gas conditioning preserving adequate mucosal function and secretion removal, could potentially contribute to decrease airways resistance, intrinsic PEEP and work of breathing, while improving patient comfort. Investigators aim to determine if the use of HFHO, as compared to standard O2, increases the number of ventilator-free days (VFDs) and alive at day 28 in patients with hypercapnic ARF admitted in an ICU, an intermediate care, or a respiratory care unit, and requiring NIV.

Evaluate safety and efficacy of application ( high flow nasal canula) in cases with mild hypercapnia, included 30 patients who were hospitalized in Mansoura University chest department with mild Hypercapnia (Pco2 range 45-60 mmhg and power of hydrogen not less 7.30) of different pulmonary disease categories (Chronic obstructive pulmonary disease acute exacerbation, pneumonia, Interstitial lung diseases, etc).

The investigators will simulate the conditions of a working, helmeted diver by using exercising, "head out" immersed subjects to test the following hypotheses: An algorithm can be developed which predicts cognitive performance in immersed exercising divers, based on the exhaled carbon dioxide (PETCO2) and the diver's inspired partial pressures of oxygen and nitrogen (PIO2 and PIN2). PETCO2 using mass spectrometry is an accurate estimate of arterial carbon dioxide (PaCO2) at rest and during immersed exercise and can be used as a PaCO2 surrogate at levels exceeding 50 mmHg and depths up to 158 fsw (gas density 6.4 g/l, similar to 165 fsw density of 6.8 g/l).

This study aimed to evaluate the effects of a novel automatic non-invasive ventilation (NIV) mode that continuously adjusts expiratory positive airway pressure (EPAP) to the lowest value that abolishes tidal expiratory flow limitation. The investigators conducted a prospective, randomized, cross-over study on stable chronic obstructive pulmonary disease (COPD) patients. Patients were studied in the hospital during two non-consecutive nights while using either fixed or adaptive EPAP. The primary outcome was the transcutaneous partial pressure of carbon dioxide. Secondary outcomes were: oxygen saturation, breathing pattern, oscillatory mechanics, patient-ventilation asynchronies, sleep quality and sleep-related respiratory events.

In an avalanche burial with an air pocket hypercapnia (and hypoxia) develops within few minutes, hypercapnia increases the rate of cooling and therefore the development of hypothermia. The Triple H Syndrome (Hypoxia, Hypercapnia, Hypothermia) occurs. This specific combination of the three parameters is unique for avalanche burial with an air pocket. Every single parameter has a substantial effect on the hemoglobin-oxygen dissociation curve, but until now no study described the combination of these three parameters. This curve will be measured under these specific conditions in a specifically developed in vitro model, to quantify its shifts and to show if there are combined effects of pCO2 and temperature. The newly developed method will be validated in comparison with an established method. The project will be performed with whole blood, drawn by healthy volunteers, in an experimental setting. The samples will be blinded to the investigator and analyzed in a randomized manner.

The purpose of this study is to show that a permissive hypercapnia during mechanical ventilation in children under general anaesthesia will improve cerebral perfusion.

The investigators hypothesize that this new nasal cannula will prevent lack of oxygen as well as reduce rebreathing of carbon dioxide under ophthalmic drapes during eye surgery.

At present, little data is available in the medical literature regarding the affects of humidification on NIMV efficacy, sleep quality and upper airway symptoms in patients undergoing nocturnal NIMV. The aim of the present pilot study is to assess the impact of two humidification systems on sleep quality, NIMV efficacy, patient-ventilator interaction, prevalence of NIMV side effects, compliance to treatment, in a group of stable patients already enrolled in a long-term nocturnal mechanical ventilation program for chronic hypercapnic respiratory failure or sleep hypoventilation.

The overall aim with this project is to investigate the effect of dexmedetomidine on control of breathing in healthy volunteers and to compare it with propofol at the same degree of sedation.