To evaluate the relationship between plasma plasminogen activator inhibitor-1 (PAI-1) and angiotensin II (Ang II) changes during treatment with imidapril and candesartan in hypertensive patients with metabolic syndrome. A total of 84 hypertensive patients with metabolic syndrome were randomized to imidapril 10 mg or candesartan 16 mg for 16 weeks. At weeks ...

Salt restriction and/or diuretic treatment convert nondippers to dippers; however, few reports have compared the relationships among the changes in asleep ambulatory blood pressure, left ventricular mass index(LVMI), and relative wall thickness between nondippers and dippers. We treated 30 never-treated hypertensive outpatients [office blood pressure (OBP) > 140/90 mmHg]with salt ...

Background: CO(2) -pneumoperitoneum (PP) is performed at varying abdominal pressures. We studied in an animal preparation the effect of increasing abdominal pressures on gas exchange during PP. Methods: Eighteen anaesthetized pigs were studied. Three abdominal pressures (8, 12 and 16 mmHg) were randomly selected in each animal. In six pigs, single-photon ...

Acute lung injury and acute respiratory distress syndrome (ARDS) occur frequently in brain-injured patients. Single organ dysfunction ventilator strategies result in a conflict between lung protective ventilation and the prevention of secondary neurological insult(s). The objectives of this study were to determine if clinical and physiological benefits of high-frequency oscillatory ...

Abstract  We present three patients with severe respiratory failure secondary to H1N1 influenza type A pneumonitis, in whom hypercapnia and respiratory acidosis were not controlled by the conventional mechanical lung ventilation or high-frequency oscillatory ventilation. Use of a pumpless arteriovenous extracorporeal carbon dioxide removal device (Novalung™, Inspiration Healthcare Ltd, Leicester, ...

BACKGROUND:: The incidence of acute lung injury (ALI) in hypoxic patients undergoing surgery is currently unknown. Previous studies have identified lung protective ventilation strategies that are beneficial in the treatment of ALI. The authors sought to determine the incidence and examine the use of lung protective ventilation strategies in patients ...

PURPOSE: To determine reciprocal and synergistic effects of acute intracranial hypertension and ARDS on neuronal and pulmonary damage and to define possible mechanisms. METHODS: Twenty-eight mechanically ventilated pigs were randomized to four groups of seven each: control; acute intracranial hypertension (AICH); acute respiratory distress syndrome (ARDS); acute respiratory distress syndrome ...

We report a case in which a 2-year-old girl who underwent a right middle and lower lung lobectomy for congenital cystic adenomatoid malformation suffered massive bleeding and developed acute respiratory distress syndrome (ARDS) during the operation. She was ventilated with a high level of F(I)O(2) (0.75-1.0), PEEP (10-20 cmH(2)O), and PIP ...

INTRODUCTION: Total liquid ventilation (TLV) with perfluorocarbons has shown to improve cardiopulmonary function in the injured and immature lung; however there remains controversy over the normal lung. Hemodynamic effects of TLV in the normal lung currently remain undetermined. This study compared changes in cardiopulmonary and circulatory function caused by either ...

The objective of this study was to determine the pharmacodynamic effects in sheep of the anaesthetic alfaxalone in a 2-hydroxypropyl-β-cyclodextrin formulation. Seven Ripollesa sheep, weighing 43.0±6.6kg, were used in the study. Twenty-four hours after instrumentation, the sheep were anesthetised with alfaxalone (2mg/kg bodyweight IV) in cyclodextrin. Heart rate, arterial blood ...

Acute lung failure is associated with high mortality and usually requires mechanical ventilation to ensure adequate gas exchange. However, mechanical ventilation itself can be associated with major complications and can aggravate pre-existing lung disease, thus contributing to morbidity and mortality. Extracorporeal gas exchange is increasingly used when conventional mechanical ventilation ...

General anaesthesia impairs respiratory function in overweight patients. We wanted to determine whether increased tidal volume (VT), with unchanged end-tidal carbon dioxide partial pressure (PETCO2), affects blood concentrations of oxygen and sevoflurane in overweight patients. The present study is a prospective, randomised, clinical study. American Society of Anesthesiologists physical status ...

Objective  To compare, ventilation using intermittent positive pressure ventilation (IPPV) with constant positive end-expiratory pressure (PEEP) and alveolar recruitment manoeuvres (RM) to classical IPPV without PEEP on gas exchange during anaesthesia and early recovery. Study design  Prospective randomized study. Animals  Twenty-four warm-blood horses, weight mean 548 ± SD 49 kg undergoing surgery for ...

Hypoxemia is considered to be the most important challenge during one-lung ventilation (OLV). Recent studies, however, have shown that one-lung ventilation can involve some lung damage and can therefore be per se a cause of hypoxemia. OLV can be associated to an injury: but the techniques used to improve oxygenation ...

BACKGROUND:: The inflammatory influence of prolonged mechanical ventilation in uninjured lungs remains a matter of controversy and largely unexplored in humans. The authors investigated pulmonary inflammation by using exhaled breath condensate (EBC) in mechanically ventilated, brain-injured patients in the absence of acute lung injury or sepsis and explored the potential ...

Background: Using a model lung connected to six different ventilators, with each ventilator in the airway pressure release ventilation mode, we measured differences in intrinsic positive end-expiratory pressure (PEEPi) during the expiratory phase and calculated the inspiratory and expiratory pressure time product (PTP) as an index of work of breathing ...

This study was designed to study effects of lung lavage versus the classical bolus instillation with a peptide-based synthetic surfactant (lucinactant) in a model of Meconium Aspiration Syndrome (MAS). Eighteen newborn lambs received meconium and were randomized to: the experimental meconium installation (eMAS) group-lambs with eMAS kept on conventional mechanical ...

To compare the acute oxygenation effects of high-frequency oscillatory ventilation (HFOV) plus inhaled nitric oxide (iNO) with pressure-controlled assist/control ventilation (PCACV) plus iNO in acute hypoxemic respiratory failure (AHRF) children. Children with AHRF, aged between 1 month and 14 years under PCACV with PEEP ≥ 10 cmH(2) O were randomly ...

BACKGROUND AND AIMS: Exaggerated pressure fluctuation between the thorax and abdomen during exercise or with pulmonary disease may challenge the gastroesophageal barrier and allow reflux of gastric juice into the esophagus. The aim of this study was to investigate the pressure differentials in the region of the gastroesophageal junction to ...

CONTEXT AND OBJECTIVE: We hypothesised that head and neck position could affect the effectiveness of ventilation with the i-gel airway. To test this hypothesis, we investigated the influence of different head and neck positions on oropharyngeal sealing pressures and ventilation scores during ventilation with i-gel. METHODS: A single, experienced supraglottic ...

BACKGROUND: A simple method for effective bronchodilator aerosol delivery while continuing continuous positive airway pressure (CPAP) would be useful in patients with severe bronchial obstruction. We assessed the effectiveness of bronchodilator aerosol delivery during CPAP generated by a small open device, the Boussignac CPAP system, as well as the optimal ...

BACKGROUND AND OBJECTIVE: While chronic non-invasive ventilation is an effective treatment in patients with chronic respiratory failure due to chest wall deformity, it is unknown whether the time to adjust to chronic ventilation depends on the type of ventilation. The aim of this study was to compare volume and pressure ...

The potential advantages of pressure-controlled over volume-controlled ventilation during laparoscopic surgery have yet to be proven. We randomly assigned 42 patients with BMI < 30 kg.m(-2) scheduled for laparoscopic cholecystectomy to receive either pressure- or volume-controlled ventilation. Compared with volume-controlled ventilation, pressure-controlled ventilation resulted in a significant decrease in mean (SD) peak ...

OBJECTIVE: In mechanically ventilated patients ready for a spontaneous breathing trial, we investigated the relationship between CO₂ response and the duration of weaning. METHODS: CO₂ response test, and maximal inspiratory (MIP) and expiratory (MEP) pressure were evaluated in 102 non-consecutive ventilated patients. CO₂ response test measures the hypercapnic drive response ...

High-frequency percussive ventilation (HFPV) may be defined as flow-regulated time-cycled ventilation that creates controlled pressure and delivers a series of high-frequency subtidal volumes in combination with low-frequency breathing cycles. In recent years, the usefulness of HFPV has been clinically assessed as an alternative to conventional mechanical ventilation. In the clinical ...

To study the correlation between intraabdominal and intrathoracic pressure in patients with suspected intraabdominal hypertension. A prospective, observational cohort study. Polyvalent intensive care unit of a University hospital. Twenty-seven medical-surgical patient dependent upon controlled mechanical ventilation due to acute respiratory failure and with several risk factors for intraabdominal hypertension (IAH). ...

OBJECTIVE: To report the use of negative pressure ventilation as a therapeutic rescue in a patient with post-operative complications of Kawashima procedure. DESIGN: Case report. SETTING: Paediatric cardiac critical care unit in a tertiary care teaching hospital. PATIENT: Nine month-old patient with single ventricle physiology developed complications after Kawashima procedure ...

ABSTRACT: Respiratory-associated variations in stroke volume and pulse pressure are frequently used to predict the response to fluid administration. However, it has been demonstrated that low tidal volume ventilation may limit their use in patients with acute respiratory distress syndrome (ARDS). In this issue, a trial investigates the value of ...

BACKGROUND:: Morbid obesity predisposes patients to lung collapse and hypoxemia during induction of anesthesia. The aim of this prospective study was to determine whether noninvasive positive pressure ventilation (NPPV) improves arterial oxygenation and end-expiratory lung volume (EELV) compared with conventional preoxygenation, and whether NPPV followed by early recruitment maneuver (RM) ...

PURPOSE OF REVIEW: Electrical impedance tomography (EIT) is an attractive method of monitoring patients during mechanical ventilation because it can provide a noninvasive continuous image of pulmonary impedance, which indicates the distribution of ventilation. This article will discuss ongoing research on EIT, with a focus on methodological aspects and limitations ...

ABSTRACT: Ventilator-induced lung injury (VILI) consists of tissue damage and a biological response resulting from the application of inappropriate mechanical forces to the lung parenchyma. The current paradigm attributes VILI to overstretching due to very high-volume ventilation (volutrauma) and cyclic changes in aeration due to very low-volume ventilation (atelectrauma); however, ...

PURPOSE: We evaluated whether oscillatory compliance (C(X5)) measured by forced oscillation technique (FOT) at 5 Hz may be useful for positive end-expiratory pressure (PEEP) optimisation. METHODS: We studied seven pigs in which lung injury was induced by broncho-alveolar lavage. The animals were ventilated in volume control mode with a tidal volume ...

Maximal inspiratory pressures (MIP) and maximal expiratory pressures (MEP) are useful indices of respiratory muscle strength in athletes. The aims of this study were: to describe the strength of the respiratory muscles of Olympic junior swim team, at baseline and after a standard physical training; and to determine if there ...

Arterial hypoxaemia remains a problem during one-lung ventilation (OLV). We determined whether a preemptive alveolar recruitment strategy (ARS) before OLV improves arterial oxygenation during OLV in patients undergoing thoracic surgery. Forty-two patients were allocated randomly to receive either a tidal volume of 10 ml kg(-1) (group C) or ARS of ...

OBJECTIVES:: Biologically variable ventilation improves lung function in acute respiratory distress models. If enhanced recruitment is responsible for these results, then biologically variable ventilation might promote distribution of exogenous surfactant to nonaerated areas. Our objectives were to confirm model predictions of enhanced recruitment with biologically variable ventilation using computed tomography ...

The paper discusses the application of a direct adaptive controller to a pressure controlled artificial ventilation problem. In pressure controlled ventilators, the manipulated variable is the maximum flow applied to the patient during the active phase (inspiration), and the regulated variable is the peak pressure at end-inspiration. This simulation case ...

Enhanced sympathetic outflow to the heart and resistance vessels greatly contributes to the onset and maintenance of neurogenic hypertension. There is a consensus that the development of hypertension (clinical and experimental) is associated with an impairment of sympathetic reflex control by arterial baroreceptors. More recently, chronic peripheral chemoreflex activation, as ...

Surfactant deficiency is a major cause of respiratory failure in newborns. We have investigated the roles of surfactant and positive end-expiratory pressure (PEEP) in the development of a functional residual capacity (FRC) and the distribution of ventilation at birth. Preterm rabbit pups (28d GA) were delivered and received either saline ...

ABSTRACT: Low tidal volume (VT 6 ml/predicted body weight) pressure limited (plateau pressure <30 cmH2O) protective ventilation as proposed by the ARDS Network was associated with an improvement in mortality and is considered the gold standard for acute respiratory distress syndrome (ARDS) ventilation strategies. Limiting plateau pressure minimizes ventilator-induced lung ...

OBJECTIVE:: To assess the effects of positive end-expiratory pressure on regional ventilation distribution in normal lung and after histamine-induced bronchoconstriction. DESIGN:: Experimental study. SETTING:: International research laboratory. SUBJECTS:: Six healthy New Zealand rabbits weighing 2.5 ± 0.1 kg. INTERVENTIONS:: Rabbits were anesthetized, tracheostomized, paralyzed, and mechanically ventilated. Synchrotron radiation computed ...

PURPOSE: To determine the feasibility of daily titration of the neurally adjusted ventilatory assist (NAVA) level in relation to the maximal diaphragmatic electrical activity (EAdi(maxSBT)) measured during a spontaneous breathing trial (SBT) during pressure support ventilation (PSV). METHODS: The study included 15 consecutive patients in whom mechanical ventilation weaning was ...

Background: This study evaluates the influence of sniffing position combined with mouth opening on the effectiveness of facemask ventilation in paralyzed pediatric patients undergoing adenotonsillectomy during sevoflurane-N(2) O anesthesia. Methods: After Institutional Ethics Committee approval, 40 children 5-11 years of age who were scheduled for an elective adenotonsillectomy operation were ...

We tested the hypothesis that an open lung strategy with recruitment maneuvers will improve oxygenation and decrease lung injury in comparison with a permissive hypercapnia strategy in preterm lambs. Preterm lambs born by operative delivery at 131 ± 1 days of gestational age (term = 150 days) were randomized to ...

Background:  Supraglottic high-frequency jet ventilation (HFJV) in laryngotracheal surgery in infants with modified jet laryngoscopes offers the surgeon an unimpaired operating field. However, supraglottic HFJV is associated with the development of high airway pressures, inadvertent positive end-expiratory pressure (PEEP) levels, and barotrauma. Methods:  We investigated the total lung volumes (TLV) ...

In this paper, we develop a neuroadaptive control architecture to control lung volume and minute ventilation with input pressure constraints that also accounts for spontaneous breathing by the patient. Specifically, we develop a pressure\mbox{-} and work-limited neuroadaptive controller for mechanical ventilation based on a nonlinear multicompartmental lung model. The control ...

We report an adolescent developing ventilation failure due to supraglottic air leakage with the use of an uncuffed hand-made tracheal tube fit to her tracheobronchial deformity. To eliminate the supraglottic air leakage, a size 2.5 laryngeal mask airway (LMA) was inserted into the oral pharynx. Most of air leakage arose ...

Background: Adenosine 5'-monophosphate (AMP) and methacholine are commonly used to assess airway hyperreactivity. However, it is not fully known whether the site of airway constriction primarily involved during challenges with either agent is similar. Objective: Using a ventilation distribution test, we investigated whether the constriction induced by each agent involves ...

BACKGROUND:: One-lung ventilation (OLV) results in alveolar proinflammatory effects, whereas their extent may depend on administration of anesthetic drugs. The current study evaluates the effects of different volatile anesthetics compared with an intravenous anesthetic and the relationship between pulmonary and systemic inflammation in patients undergoing open thoracic surgery. METHODS:: Sixty-three ...

BACKGROUND:: Guidelines for the management of a difficult airway recommend performing a cricothyrotomy in a "can't intubate/can't ventilate" situation. We investigated the tidal volumes delivered by controlled and spontaneous ventilation by seven commercially available cricothyrotomy sets (cuffed: Quicktrach II, Portex Cricothyroidotomy Kit, and Melker cuffed cannula and uncuffed: Airfree, 4.0-mm ...

Background: Anaesthesia based on inhalational agents has profound effects on chest wall configuration and breathing pattern. The effects of propofol are less well characterised. The aim of the current study was to evaluate the effects of propofol anaesthesia on chest wall motion during spontaneous breathing and positive pressure ventilation. Methods: ...