It was hypothesised that noninvasive positive-pressure ventilation (NPPV) applied during walking prevents exercise-induced hypoxaemia and improves exercise performance in severe chronic obstructive pulmonary disease (COPD) patients already receiving long-term NPPV. A total of 20 COPD patients (mean+/-sd age 65.1+/-8.7 yrs, forced expiratory volume in one second 27+/-8% predicted and total ...

OBJECTIVE: Randomized controlled trials (RCTs) investigating various lung-protective ventilation modes or strategies in newborn infants have failed to show clear differences in mortality or bronchopulmonary dysplasia. This review tries to identify possible reasons for this observation, applying modern concepts on ventilator-induced lung injury and lung-protective ventilation. DATA SOURCE: Published RCTs ...

Traditional management of neonatal respiratory failure has been accomplished with mechanical ventilation delivered by time-cycled, pressure-limited techniques. Although easy to use, this modality results in the delivery of tidal volumes that vary according to pulmonary compliance. In contrast, volume-targeted ventilation delivers a selected tidal volume at variable peak inspiratory pressure, ...

OBJECTIVE: To test the feasibility of applying noninvasive ventilation (NIV) using a prototype algorithm implemented in a bilevel ventilation device designed to adjust pressure support (PS) to maintain a clinician-set alveolar ventilation in patients with acute respiratory failure after initial stabilization. DESIGN AND SETTING: Prospective crossover interventional study in an ...

INTRODUCTION: Hyperventilation during cardiopulmonary resuscitation is detrimental to survival. Several clinical studies of ventilation during hospital and out-of-hospital cardiac arrest have demonstrated respiratory rates far in excess of the 10 min(-1) recommended by the ERC. We observed detailed ventilation variables prospectively during manual ventilation of 12 cardiac arrest patients treated ...

AIM: To test the hypothesis that in volume targeted ventilation modes, ventilator performance would vary according to ventilator type. METHODS: Four neonatal ventilators: Draeger Babylog 8000 (Draeger Medical, Germany), SLE 5000 infant ventilator (SLE systems, UK), Stephanie paediatric ventilator (F. Stephan Biomedical, German) and V.I.P. Bird gold (Viasys Healthcare, USA) ...

PURPOSE OF REVIEW: Mechanical ventilation is a common intervention provided by pediatric intensivists. This fact notwithstanding, the management of mechanical ventilation in pediatrics is largely guided by a few pediatric trials along with careful interpretation and application of adult data. RECENT FINDINGS: A low tidal volume, pressure limited approach to ...

CASE DESCRIPTION: A 9-year-old dog was evaluated for traumatic cervical myelopathy after a surgical attempt to realign and stabilize the C2 and C3 vertebrae. CLINICAL FINDINGS: The dog could not ventilate spontaneously and was tetraplegic; positive-pressure ventilation (PPV) was maintained. Myelography and computed tomography revealed spinal cord compression with subluxation ...

The need for conventional mechanical ventilation (CMV) is a common one in the neonatal intensive care unit (NICU). The goals of CMV are to facilitate adequate gas exchange, minimize the risk of lung injury/damage, decrease the patient's work of breathing, and optimize the patient's comfort. Although time-cycled, pressure-limited ventilation remains ...

PURPOSE OF REVIEW: To discuss the recent literature concerning the use of noninvasive ventilation for hypoxemic acute respiratory failure. RECENT FINDINGS: The benefits of noninvasive ventilation for patients with hypoxemic acute respiratory failure are unclear. In immunocompromised patients and following thoracic surgery, there is a strong rationale for using noninvasive ...

PURPOSE OF REVIEW: The aim of this article is to discuss the various factors that influence aerosol delivery in mechanically ventilated patients and clarify optimal techniques for aerosol administration in this patient population. Clinical use of various inhaled therapies in patients receiving invasive and noninvasive mechanical ventilation is also discussed. ...

BACKGROUND: Institutional transmission of airborne infections such as tuberculosis (TB) is an important public health problem, especially in resource-limited settings where protective measures such as negative-pressure isolation rooms are difficult to implement. Natural ventilation may offer a low-cost alternative. Our objective was to investigate the rates, determinants, and effects of ...

PURPOSE: The aim of this study was to assess if common mobile communication systems would cause significant interference on mechanical ventilation devices and at what distances would such interference occur. MATERIALS AND METHODS: We tested all the invasive and noninvasive ventilatory devices used within our region. This consisted of 2 ...

BACKGROUND: The objective of this study was to determine the intracranial, cardiovascular and respiratory changes induced by conversion to high-frequency oscillator ventilation from conventional mechanical ventilation at increasing airway pressures. METHODS: In this study, 11 anaesthetized sheep had invasive cardiovascular and intracranial monitors placed. Lung injury was induced by saline ...

BACKGROUND: Lung injury associated with the acute respiratory distress syndrome can be exacerbated by improper mechanical ventilation creating a secondary injury known as ventilator-induced lung injury (VILI). We hypothesized that VILI could be caused in part by alveolar recruitment/derecruitment resulting in gross tearing of the alveolus. OBJECTIVES: The exact mechanism ...

Infrequent training of artificial ventilation in dental facilities implies poor performance of this procedure under CPR. Gastric inflation is a significant issue when ventilation is performed on an unprotected airway. An Easy Grip (EG) Bag-Valve-Mask Resuscitator, a Laryngeal Tube (LT), size #5, and a SMART BAG (SB) resuscitator, a pressure-limiting ...

BACKGROUND: Patients with acute respiratory distress syndrome and acute lung injury require mechanical ventilatory support. Acute respiratory distress syndrome and acute lung injury are further complicated by ventilator-induced lung injury. Lung-protective ventilation strategies may lead to improved survival. OBJECTIVES: To assess the effects of ventilation with lower tidal volume on ...

QUESTION: What is the effect of the Mapleson C circuit compared with the Laerdal circuit in removing secretions and improving ventilation and gas exchange during manual hyperinflation? DESIGN: Prospective, randomised, cross-over trial. PARTICIPANTS: Twenty patients from a tertiary-level intensive care unit who were being mechanically ventilated. INTERVENTION: Manual hyperinflation in ...

The effects of hemodialysis (HD) on pulmonary function are still controversial. The objective of this study was to evaluate the effect of intermittent hemodialysis (IHD) and sustained low-efficiency dialysis (SLED) on the respiratory mechanics of ICU patients under invasive mechanical ventilation. We prospectively studied 31 patients. Laboratory and respiratory evaluation ...

Airway pressure release ventilation (APRV) is a relatively new mode of mechanical ventilation (MV) first described in animal studies in 1987 and in humans in 1988. It is a time-triggered, time-cycled, pressure-limited mode where a high level of continuous positive airway pressure (CPAP) is maintained with brief regular releases in ...

BACKGROUND: The AnaConDa filter permits administration of volatile anesthetic without the use of an anesthesia machine. It is intended for use in the intensive care unit. METHODS: We studied the AnaConDa reflection filter on the bench and in anesthetized patients. The bench analysis used a test lung, a gas analyzer, ...

Amniotic fluid embolism (AFE) syndrome, a catastrophic cause of respiratory failure typically occurs during labour, or soon after delivery. Systemic hypotension is the most prominent haemodynamic alteration documented in patients with AFE, a consequence principally of severe left-sided heart failure. A 22-year-old female was admitted to the respiratory intensive care ...

Human physiology changes are often amplified in disease states and may be altered when a patient is mechanically ventilated. Normally, systolic blood pressure is slightly lower during inspiration than expiration due to the change in intrathoracic pressure. Pulsus paradoxus is a phenomenon in which the difference in systolic blood pressure ...

Patients with chronic obstructive pulmonary disease (COPD) are characterized by increased work of breathing (WOB) and ventilatory muscle dysfunction. Mechanical ventilation is applied to unload the WOB; rest respiratory muscles decrease arterial partial pressure of carbon dioxide (PaCO2) and treat hypoxemia. Since patients' needs are not static, ventilator settings have ...

Summary The aim of this prospective observational study was to document patterns of ventilation during manual hyperinflation by physiotherapists. Manual hyperinflation with a Mapleson-F system was performed on the same patients on two consecutive days. Patterns of ventilation were recorded using a heated pneumotachometer, pressure transducer and custom designed data ...

BACKGROUND: Noninvasive positive-pressure ventilation (NPPV) delivers air at a high flow, which is associated with airway mucosal drying and impaired airway functioning. OBJECTIVES: To examine the effects of mechanical ventilation parameters on relative humidity and absolute humidity during NPPV, and to evaluate the effect of a heated passover humidifier on ...

BACKGROUND: Inhalation of hyperbaric oxygen (HBO) has been reported to decrease arterial oxygen tension (PaO(2)) in the early period after exposure. The current investigation aimed at evaluating whether and to what extent arterial blood gases were affected in mechanically ventilated intensive care patients within 6 h after HBO treatment. METHODS: ...

There has been much clinical and academic interest in the use of noninvasive positive-pressure ventilation (NPPV) in patients with acute and chronic respiratory failure. The use of NPPV in appropriately selected patients improves survival and decreases the need for endotracheal intubation. The most commonly used interfaces for NPPV are nasal ...

PURPOSE: The very high solubility of carbon monoxide (CO) in blood suggests that its elimination depends predominantly on ventilation and not perfusion. Nevertheless, hyperventilation is not used for CO elimination because of the adverse effects of hypocapnia. With isocapnic hyperpnea (IH), ventilation can be increased considerably without hypocapnia. This raises ...

INTRODUCTION: To prevent further lung damage in patients with acute respiratory distress syndrome (ARDS), it is important to avoid overdistension and cyclic opening and closing of atelectatic alveoli. Previous studies have demonstrated protective effects of using low tidal volume (VT), moderate positive end-expiratory pressure and low airway pressure. Aspiration of ...

INTRODUCTION: The respiratory variation in pulse pressure (PP) has been established as a dynamic variable of cardiac preload which indicates fluid responsiveness in mechanically ventilated patients. The impact of acute changes in cardiac performance on respiratory fluctuations in PP has not been evaluated until now. We used cardiac resynchronization therapy ...

INTRODUCTION: There are several ventilator modes that are used for maintenance mechanical ventilation but no conclusive evidence that one mode of ventilation is better than another. Vibration response imaging is a novel bedside imaging technique that displays vibration energy of lung sounds generated during the respiratory cycle as a real-time ...

OBJECTIVE: We set out to evaluate the efficacy of passive inspiratory gas conditioning in mechanically ventilated neonates and compared it with that of a heated humidifier (HH). DESIGN: Prospective, randomized, controlled study. SETTING: Neonatal and pediatric intensive care unit. PATIENTS: Fourteen mechanically ventilated neonates nursed in incubators. INTERVENTIONS: The HH ...

BACKGROUND: Our objective was to study the long-term effects of non-invasive positive pressure ventilation (NPPV) on lung function and gas exchange in patients with the obesity hypoventilation syndrome (OHS). DESIGN: Prospective observational study in OHS patients performing NPPV over a period of 24 months. RESULTS: We studied 35 clinically stable ...

BACKGROUND AND OBJECTIVE: We investigated the effects of prone position on respiratory dead space and gas exchange in 14 anaesthetized healthy patients undergoing elective posterior spinal surgery of more than 3 h of duration. METHODS: The patients received a total intravenous anaesthetic with propofol/remifentanil/cisatracurium. They were ventilated at a tidal ...

Production of two related indole diterpenes (differing by a dimethyl leucine side chain) by Aspergillus alliaceus was improved through several pilot scale fermentations. Media were optimized through focus primarily on initial increases, as well as mid-cycle additions, of carbon and nitrogen sources. Fermentation conditions were improved by varying ventilation conditions ...

A young male with no pre-operative medical illness underwent corrective surgery for a deviated nasal septum under general anesthesia. At the end of surgery, patient was extubated but went into severe laryngospasm that did not improve with gentle Intermittent Positive Pressure Ventilation (IPPV) and small dose of Suxamethonium. As the ...

One-lung ventilation is limited by hypoventilation and hypoxemia because of increasing airway pressure and intrapulmonary shunt. Previous clinical studies compared pressure-controlled versus volume-controlled ventilation during one-lung ventilation in patients with pre-existing pulmonary disease. We studied 50 patients undergoing thoracotomy and one-lung ventilation because of cardiovascular disease. After two-lung ventilation with ...

BACKGROUND: The mechanism responsible for chronic hypercapnic respiratory failure (HRF) in patients with COPD remains unclear. In this study, we tested the hypothesis that chronic HRF in patients with COPD is associated with low-frequency fatigue (LFF) of the diaphragm. METHODS: To test this hypothesis, we measured the twitch transdiaphragmatic pressure ...

Management of acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS) is largely supportive, with the use of mechanical ventilation being a central feature. Recent advances in the understanding of ALI/ARDS and mechanical ventilation have revealed that lung-protective ventilation strategies may attenuate ventilator-associated lung injury and improve patient ...

Flail chest after blunt trauma usually requires good pain control and positive pressure support. Continuous negative extrathoracic pressure (CNEP) causes a splinting effect around the anterior chest wall and upper abdomen which increases functional residual capacity and improves lung mechanics. We report an 82-year-old woman with flail chest after cardiopulmonary ...

PURPOSE: To investigate the efficacy and safety of intrapulmonary percussive ventilation (IPV) in obese patients, we assessed their respiratory and hemodynamic functions during IPV superimposed on conventional ventilation. MATERIALS AND METHODS: Ten obese patients with acute respiratory failure due to compression atelectasis who had not improved by conventional ventilation were ...

Major experimental surgery on laboratory animals requires adequate anesthesia and ventilation to keep the animal alive throughout the procedure. A ventilator is a machine that helps the anesthesized animal breathe through an endotracheal tube by pumping a volume of gas (oxygen, air, or other gaseous mixtures), comparable with the normal ...

Acute respiratory failure is manifested clinically as a patient with variable degrees of respiratory distress, but characteristically an abnormal arterial blood partial pressure of oxygen or carbon dioxide. The application of mechanical ventilation in this setting can be life-saving. An emerging body of clinical and basic research, however, has highlighted ...

OBJECTIVE: Volume-targeted modes are designed to deliver a constant tidal volume (V(t)) at lowest possible pressure independently of changes in compliance, resistance, and leak of the respiratory system. We examined whether these volume-targeted modes respond rapidly enough to sudden changes in respiratory mechanics (e.g., selective intubation, surfactant administration, endotracheal tube ...

OBJECTIVE: To evaluate the effect of increased intra-abdominal pressure (IAP) on the systolic and pulse pressure variations induced by positive pressure ventilation in a porcine model. DESIGN AND SETTING: Experimental study in a research laboratory. SUBJECTS: Seven mechanically ventilated and instrumented pigs prone to normovolaemia and hypovolaemia by blood withdrawal. ...

BACKGROUND: A substantial percentage of the aerosol produced by a nebulizer is lost down the expiratory limb of the ventilator circuit. We describe a method for the capture, return, and re-aerosolization of that undelivered aerosol. METHODS: We designed an expiratory-limb setup in which an "entraining jet" of gas accelerates unused ...

BACKGROUND: This study reports the effect of thoracentesis on respiratory mechanics and gas exchange in patients receiving mechanical ventilation. Study design: Prospective. SETTING: University hospital. PATIENTS: Eight patient receiving mechanical ventilation with unilateral (n = 7) or bilateral (n = 1) large pleural effusions. INTERVENTION: Therapeutic thoracentesis (n = 9). ...

The occurrence of acute respiratory distress syndrome (ARDS), is now common in intensive care units throughout the world. The diagnosis of ARDS is based on a definition that includes bilateral pulmonary infiltrates on chest radiographs, impaired oxygenation, and the absence of clinical evidence of elevated left atrial pressure. ARDS is ...

Liquid ventilation using perfluorochemicals (PFC) offers clear theoretical advantages over gas ventilation, such as decreased lung damage, recruitment of collapsed lung regions, and lavage of inflammatory debris. We present a total liquid ventilator designed to ventilate patients with completely filled lungs with a tidal volume of PFC liquid. The two ...