The Experts below are selected from a list of 89982 Experts worldwide ranked by ideXlab platform
Anton H Van Kaam - One of the best experts on this subject based on the ideXlab platform.
-
lung protective Ventilation in neonatology
2011Co-Authors: Anton H Van KaamAbstract:Ventilator-induced lung injury (VILI) is considered an important risk factor in the development of bronchopulmonary dysplasia (BPD) and is primarily caused by overdistension (volutrauma) and repetitive opening and collapse (atelectrauma) of terminal lung units. Lung-protective Ventilation should therefore aim to reduce tidal volumes, and recruit and stabilize atelectatic lung units (open lung Ventilation strategy). This review will summarize the available evidence on lung-protective Ventilation in neonatology, discussing both High-Frequency Ventilation (HFV) and positive pressure Ventilation (PPV). It shows that HFV does not appear to have a clear benefit over PPV, although most studies failed to apply a true open lung Ventilation strategy during HFV. The evidence on the optimal tidal volume, positive end-expiratory pressure and the role for lung recruitment during lung-protective PPV is extremely limited. Volume-targeted Ventilation seems to be a promising mode in terms of lung protection, but more studies are needed. Due to the lack of convincing evidence, lung-protective Ventilation and modes seem to be implemented in daily clinical practice at a slow pace.
-
effect of lung recruitment on pulmonary systemic and ductal blood flow in preterm infants
2009Co-Authors: Koert De Waal, Nick Evans, Johanna Van Der Lee, Anton H Van KaamAbstract:Objective To determine the effect of lung recruitment on pulmonary, systemic, and ductal blood flow in preterm infants treated with primary High-Frequency Ventilation (HFV). Study design Thirty-four infants (median gestational age, 28 weeks) were included in this prospective cohort study. Changes in oxygenation in response to stepwise changes in the continuous distending pressure (CDP) were used to monitor lung recruitment during HFV. For each individual patient, the opening pressure (CDPo), closing pressure (CDPc), and optimal pressure (CDPopt) were determined. Ultrasound measurements of right ventricular output (RVO), superior vena cava (SVC), and ductus arteriosus (DA) flow were performed at the start of recruitment (CDPs), CDPo, and CDPopt. Results Increasing the CDP from 8 (CDPs) to 20 (CDPo) cmH 2 O resulted in a decreased RVO (mean difference, −17%; 95% CI, −24, −10%) and unchanged SVC flow and ductal shunting. Transient low RVO and SVC flow values at CDPo were seen in 3 and 2 infants, respectively. Conclusions Lung recruitment during HFV in preterm infants does not appear to result in clinically relevant changes in pulmonary, systemic, and ductal blood flow.
-
feasibility of weaning and direct extubation from open lung high frequency Ventilation in preterm infants
2009Co-Authors: Alice S Van Velzen, Anne De Jaegere, Johanna Van Der Lee, Anton H Van KaamAbstract:Objective: High-Frequency Ventilation (HFV) is increasingly used in preterm infants, but data on weaning and extubation are limited. We aimed to establish if weaning the continuous distending pressure (CDP) below 8 cm H2O and the Fio2 below 0.30 is feasible in preterm infants on open lung HFV and if these settings result in successful extubation. Design: Retrospective cohort study. Setting: Neonatal intensive care unit in a university hospital. Patients: Preterm infants ventilated and directly extubated from HFV between January 2003 and August 2005. Measurements and Main Results: Data on patient characteristics, ventilator settings, gas exchange, respiratory support after extubation and the number of patients failing extubation (i.e., reintubation within 48 hr) were retrospectively collected. Two hundred fourteen infants, accounting for 242 Ventilation periods, were included in the study. The CDP, but not the Fio2, decreased significantly in the 24-hr period before extubation, resulting in a mean CDP of 6.8 ± 1.6 cm H2O and a mean Fio2 of 0.25 at the time of extubation. At these settings, 193 (90%) infants were successfully extubated. Multivariate logistic regression analysis showed that birth weight was the only independent variable positively associated with successful extubation. Conclusion: This study shows that weaning the CDP below 8 cm H2O with an Fio2 below 0.30 is feasible during open lung HFV and extubation at these settings can be successful in preterm infants. In our series, a 90% success rate was observed. The value of this approach should be prospectively compared with conventional weaning and extubation strategies.
-
lung recruitment using oxygenation during open lung high frequency Ventilation in preterm infants
2006Co-Authors: Anne De Jaegere, Mariette B Van Veenendaal, Agnes Michiels, Anton H Van KaamAbstract:Rationale: Changes in oxygenation are often used to guide the recruitment procedure during open lung High-Frequency Ventilation in preterm infants. However, data on the feasibility and safety of this approach in daily clinical practice are limited.Objective: To prospectively collect data on ventilator settings, gas exchange, and circulatory parameters before and after surfactant therapy during open lung High-Frequency Ventilation.Methods: In 103 preterm infants with respiratory distress syndrome, the opening, closing, and optimal pressures were determined during High-Frequency Ventilation by increasing and decreasing stepwise the continuous distending pressure, defining optimal recruitment as adequate oxygenation using a fraction of inspired oxygen not exceeding 0.25. This procedure was repeated after each surfactant treatment.Measurements and Main Results: The mean presurfactant opening and optimal continuous distending pressures were, respectively, 20.5 ± 4.3 and 14.0 ± 4.0 cm H2O, with a fraction of in...
James Mapstone - One of the best experts on this subject based on the ideXlab platform.
-
high frequency Ventilation versus conventional Ventilation for treatment of acute lung injury and acute respiratory distress syndrome
2013Co-Authors: Hannah Wunsch, James MapstoneAbstract:Background High frequency oscillation is an alternative to conventional mechanical Ventilation that is sometimes used to treat patients with acute respiratory distress syndrome, but effects on oxygenation, mortality and adverse clinical outcomes are uncertain. This review was originally published in 2004 and was updated in 2011. Objectives To determine clinical and physiological effects of high frequency oscillation (HFO) in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) compared to conventional Ventilation. Search methods We electronically searched CENTRAL (Ovid), MEDLINE (Ovid), EMBASE (Ovid), and ISI (from inception to March 2011). The original search was performed in 2002. We manually searched reference lists from included studies and review articles; searched conference proceedings of the American Thoracic Society (1994 to 2010), Society of Critical Care Medicine (1994 to 2010), European Society of Intensive Care Medicine (1994 to 2010), and American College of Chest Physicians (1994 to 2010); contacted clinical experts in the field; and searched for unpublished and ongoing trials in clinicaltrials.gov and controlled-trials.com. Selection criteria Randomized controlled clinical trials comparing treatment using HFO with conventional mechanical Ventilation for children and adults diagnosed with ALI or ARDS. Data collection and analysis Three authors independently extracted data on clinical, physiological, and safety outcomes according to a predefined protocol. We contacted investigators of all included studies to clarify methods and obtain additional data. We used random-effects models in the analyses. Main results Eight RCTs (n = 419) were included; almost all patients had ARDS. The risk of bias was low in six studies and unclear in two studies. The quality of evidence for hospital and six-month mortality was moderate and low, respectively. The ratio of partial pressure of oxygen to inspired fraction of oxygen at 24, 48, and 72 hours was 16% to 24% higher in patients receiving HFO. There were no significant differences in oxygenation index because mean airway pressure rose by 22% to 33% in patients receiving HFO (P < 0.01). In patients randomized to HFO, mortality was significantly reduced (RR 0.77, 95% CI 0.61 to 0.98; P = 0.03; 6 trials, 365 patients, 160 deaths) and treatment failure (refractory hypoxaemia, hypercapnoea, hypotension, or barotrauma) was less likely (RR 0.67, 95% CI 0.46 to 0.99; P = 0.04; 5 trials, 337 patients, 73 events). Other risks, including adverse events, were similar. We found substantial between-trial statistical heterogeneity for physiological (I2 = 21% to 95%) but not clinical (I2 = 0%) outcomes. Pooled results were based on few events for most clinical outcomes. Authors' conclusions The findings of this systematic review suggest that HFO was a promising treatment for ALI and ARDS prior to the uptake of current lung protective Ventilation strategies. These findings may not be applicable with current conventional care, pending the results of large multi-centre trials currently underway.
-
high frequency Ventilation versus conventional Ventilation for the treatment of acute lung injury and acute respiratory distress syndrome a systematic review and cochrane analysis
2005Co-Authors: Hannah Wunsch, James Mapstone, Jukka TakalaAbstract:In this review, we examine outcomes from using High-Frequency Ventilation compared with conventional Ventilation as therapy for acute lung injury and acute respiratory distress syndrome in children and adults. We conducted a systematic search of the literature based on the guidelines of the Cochrane Collaboration. Two trials met the inclusion criteria; one recruited children (n = 58), and the other recruited adults (n = 148). Both trials used a High-Frequency oscillatory ventilator as the intervention and included variable use of lung-volume recruitment strategies. The intervention groups showed a trend toward less 30-day mortality (children: relative risk [RR], 0.83; 95% confidence interval [CI], 0.43–1.62; adults: RR, 0.72; 95% CI, 0.50–1.03), although neither study showed a statistically significant difference. Similarly, there was no statistically significant difference between the intervention and control groups for “total length of ventilator days.” There was a statistically significant reduction in the risk of requiring supplemental oxygen among survivors at 30 days in the pediatric study (RR, 0.36; 95% CI, 0.14–0.93). Overall there is not enough evidence to conclude that High-Frequency Ventilation reduces mortality or long-term morbidity in patients with acute lung injury or acute respiratory distress syndrome. (This review is published as a Cochrane Review in The Cochrane Library 2004, Issue 3. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and The Cochrane Library should be consulted for the most recent version of the Review.)
Hannah Wunsch - One of the best experts on this subject based on the ideXlab platform.
-
high frequency Ventilation versus conventional Ventilation for treatment of acute lung injury and acute respiratory distress syndrome
2013Co-Authors: Hannah Wunsch, James MapstoneAbstract:Background High frequency oscillation is an alternative to conventional mechanical Ventilation that is sometimes used to treat patients with acute respiratory distress syndrome, but effects on oxygenation, mortality and adverse clinical outcomes are uncertain. This review was originally published in 2004 and was updated in 2011. Objectives To determine clinical and physiological effects of high frequency oscillation (HFO) in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) compared to conventional Ventilation. Search methods We electronically searched CENTRAL (Ovid), MEDLINE (Ovid), EMBASE (Ovid), and ISI (from inception to March 2011). The original search was performed in 2002. We manually searched reference lists from included studies and review articles; searched conference proceedings of the American Thoracic Society (1994 to 2010), Society of Critical Care Medicine (1994 to 2010), European Society of Intensive Care Medicine (1994 to 2010), and American College of Chest Physicians (1994 to 2010); contacted clinical experts in the field; and searched for unpublished and ongoing trials in clinicaltrials.gov and controlled-trials.com. Selection criteria Randomized controlled clinical trials comparing treatment using HFO with conventional mechanical Ventilation for children and adults diagnosed with ALI or ARDS. Data collection and analysis Three authors independently extracted data on clinical, physiological, and safety outcomes according to a predefined protocol. We contacted investigators of all included studies to clarify methods and obtain additional data. We used random-effects models in the analyses. Main results Eight RCTs (n = 419) were included; almost all patients had ARDS. The risk of bias was low in six studies and unclear in two studies. The quality of evidence for hospital and six-month mortality was moderate and low, respectively. The ratio of partial pressure of oxygen to inspired fraction of oxygen at 24, 48, and 72 hours was 16% to 24% higher in patients receiving HFO. There were no significant differences in oxygenation index because mean airway pressure rose by 22% to 33% in patients receiving HFO (P < 0.01). In patients randomized to HFO, mortality was significantly reduced (RR 0.77, 95% CI 0.61 to 0.98; P = 0.03; 6 trials, 365 patients, 160 deaths) and treatment failure (refractory hypoxaemia, hypercapnoea, hypotension, or barotrauma) was less likely (RR 0.67, 95% CI 0.46 to 0.99; P = 0.04; 5 trials, 337 patients, 73 events). Other risks, including adverse events, were similar. We found substantial between-trial statistical heterogeneity for physiological (I2 = 21% to 95%) but not clinical (I2 = 0%) outcomes. Pooled results were based on few events for most clinical outcomes. Authors' conclusions The findings of this systematic review suggest that HFO was a promising treatment for ALI and ARDS prior to the uptake of current lung protective Ventilation strategies. These findings may not be applicable with current conventional care, pending the results of large multi-centre trials currently underway.
-
high frequency Ventilation versus conventional Ventilation for the treatment of acute lung injury and acute respiratory distress syndrome a systematic review and cochrane analysis
2005Co-Authors: Hannah Wunsch, James Mapstone, Jukka TakalaAbstract:In this review, we examine outcomes from using High-Frequency Ventilation compared with conventional Ventilation as therapy for acute lung injury and acute respiratory distress syndrome in children and adults. We conducted a systematic search of the literature based on the guidelines of the Cochrane Collaboration. Two trials met the inclusion criteria; one recruited children (n = 58), and the other recruited adults (n = 148). Both trials used a High-Frequency oscillatory ventilator as the intervention and included variable use of lung-volume recruitment strategies. The intervention groups showed a trend toward less 30-day mortality (children: relative risk [RR], 0.83; 95% confidence interval [CI], 0.43–1.62; adults: RR, 0.72; 95% CI, 0.50–1.03), although neither study showed a statistically significant difference. Similarly, there was no statistically significant difference between the intervention and control groups for “total length of ventilator days.” There was a statistically significant reduction in the risk of requiring supplemental oxygen among survivors at 30 days in the pediatric study (RR, 0.36; 95% CI, 0.14–0.93). Overall there is not enough evidence to conclude that High-Frequency Ventilation reduces mortality or long-term morbidity in patients with acute lung injury or acute respiratory distress syndrome. (This review is published as a Cochrane Review in The Cochrane Library 2004, Issue 3. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and The Cochrane Library should be consulted for the most recent version of the Review.)
D Mitanchez - One of the best experts on this subject based on the ideXlab platform.
-
congenital cytomegalovirus infection manifesting as neonatal persistent pulmonary hypertension report of two cases
2011Co-Authors: Elizabeth Walternicolet, Magali Leblanc, Marianne Leruezville, P Hubert, D MitanchezAbstract:Various neonatal symptoms can lead to a diagnosis of congenital CMV infection. We report two cases of persistent pulmonary hypertension in relation with congenital CMV infection following maternal primary infection and reinfection, respectively. Both infants had severe refractory hypoxemia, requiring High-Frequency Ventilation, inhaled nitric oxide and inotropic support. One of them required extracorporeal membrane oxygenation for five days. Ganciclovir therapy was attempted in the two cases on day 12 postnatal. One of the infant died on day 15 postnatal. The other survived and is developing uneventfully at 15 months of age. Conclusion: Neonatal persistent pulmonary hypertension can be the consequence of congenital CMV infection. Intensive respiratory support and IV ganciclovir are indicated in case of life-threatening condition.
-
prenatal prognosis in isolated congenital diaphragmatic hernia
2008Co-Authors: Valerie Datindorriere, Elizabeth Walternicolet, Sarah Rouzies, Pierre Taupin, Alexandra Benachi, P Sonigo, D MitanchezAbstract:Objective A monocentric retrospective study of 79 neonates with isolated diaphragmatic hernia antenatally diagnosed was performed to identify prenatal parameters that may characterize the severity of the disease. Study Design Postnatal treatment protocol included early high frequency Ventilation, inhaled nitric oxide, and delayed surgery. Postnatal survival rate was 63.3%. Results Age at diagnosis, polyhydramnios, and left ventricle/right ventricle index were not related with survival. None of the 9 left diaphragmatic hernias with intraabdominal stomach died. Neonatal mortality was significantly related with the side of the defect, intrathoracic position of the liver, the ratio of fetal lung area to head circumference value, and fetal lung volume ratio measured by resonance magnetic imaging. Conclusion No prenatal factor alone firmly predicts neonatal outcome. Clinicians should help stratify the severity of the disease and compare accurately different postnatal therapeutic strategies.
Peter A. Dargaville - One of the best experts on this subject based on the ideXlab platform.
-
The Deflation Limb of the Pressure–Volume Relationship in Infants during High-Frequency Ventilation
2013Co-Authors: David G Tingay, John F. Mills, Colin J Morley, Anastasia Pellicano, Peter A. DargavilleAbstract:Rationale: The importance of applying High-Frequency oscillatory Ventilation with a high lung volume strategy in infants is well established. Currently, a lack of reliable methods for assessing lung volume limits clinicians ’ ability to achieve the optimum volume range. Objectives: To map the pressure–volume relationship of the lung during High-Frequency oscillatory Ventilation in infants, to determine at what point Ventilation is being applied clinically, and to describe the relationship between airway pressure, lung volume, and oxygenation. Methods: In 12 infants, a partial inflation limb and the deflation limb of the pressure–volume relationship were mapped using a quasi-static lung volume optimization maneuver. This involved stepwise airway pressure increments to total lung capacity, followed by decrements until the closing pressure of the lung was identified. Measurements and Main Results: Lung volume and oxygen saturation were recorded at each airway pressure. Lung volume was measured using respiratory inductive plethysmography. A distinct deflation limb could be mapped in each infant. Overall, oxygenation and lung volume were improved by applying Ventilation on the deflation limb. Maximal lung volume and oxygenation occurred on the deflation limb at a mean airway pressure of 3 and 5 cm H 2O below the airway pressure approximating total lung capacity, respectively. Conclusions: Using current Ventilation strategies, all infants were being ventilated near the inflation limb. It is possible to delineate the deflation limb in infants receiving High-Frequency oscillatory Ventilation; in doing so, greater lung volume and oxygenation can be achieved, often at lower airway pressures
-
respiratory support in meconium aspiration syndrome a practical guide
2012Co-Authors: Peter A. DargavilleAbstract:Meconium aspiration syndrome (MAS) is a complex respiratory disease of the term and near-term neonate. Inhalation of meconium causes airway obstruction, atelectasis, epithelial injury, surfactant inhibition, and pulmonary hypertension, the chief clinical manifestations of which are hypoxaemia and poor lung compliance. Supplemental oxygen is the mainstay of therapy for MAS, with around one-third of infants requiring intubation and mechanical Ventilation. For those ventilated, high ventilator pressures, as well as a relatively long inspiratory time and slow ventilator rate, may be necessary to achieve adequate oxygenation. High-Frequency Ventilation may offer a benefit in infants with refractory hypoxaemia and/or gas trapping. Inhaled nitric oxide is effective in those with pulmonary hypertension, and other adjunctive therapies, including surfactant administration and lung lavage, should be considered in selected cases. With judicious use of available modes of Ventilation and adjunctive therapies, infants with even the most severe MAS can usually be supported through the disease, with an acceptably low risk of short- and long-term morbidities.
-
randomized controlled trial of lung lavage with dilute surfactant for meconium aspiration syndrome
2011Co-Authors: Peter A. Dargaville, John F. Mills, Mei-jy Jeng, Beverley Copnell, Ismail Haron, David G Tingay, Jaafar Rohana, Lindsay Mildenhall, Anushree NarayananAbstract:Objective To evaluate whether lung lavage with surfactant changes the duration of mechanical respiratory support or other outcomes in meconium aspiration syndrome (MAS). Study design We conducted a randomized controlled trial that enrolled ventilated infants with MAS. Infants randomized to lavage received two 15-mL/kg aliquots of dilute bovine surfactant instilled into, and recovered from, the lung. Control subjects received standard care, which in both groups included high frequency Ventilation, nitric oxide, and, where available, extracorporeal membrane oxygenation (ECMO). Results Sixty-six infants were randomized, with one ineligible infant excluded from analysis. Median duration of respiratory support was similar in infants who underwent lavage and control subjects (5.5 versus 6.0 days, P = .77). Requirement for high frequency Ventilation and nitric oxide did not differ between the groups. Fewer infants who underwent lavage died or required ECMO: 10% (3/30) compared with 31% (11/35) in the control group (odds ratio, 0.24; 95% confidence interval, 0.060-0.97). Lavage transiently reduced oxygen saturation without substantial heart rate or blood pressure alterations. Mean airway pressure was more rapidly weaned in the lavage group after randomization. Conclusion Lung lavage with dilute surfactant does not alter duration of respiratory support, but may reduce mortality, especially in units not offering ECMO.
-
the deflation limb of the pressure volume relationship in infants during high frequency Ventilation
2006Co-Authors: David G Tingay, John F. Mills, Colin J Morley, Anastasia Pellicano, Peter A. DargavilleAbstract:Rationale: The importance of applying High-Frequency oscillatory Ventilation with a high lung volume strategy in infants is well established. Currently, a lack of reliable methods for assessing lung volume limits clinicians' ability to achieve the optimum volume range.Objectives: To map the pressure–volume relationship of the lung during High-Frequency oscillatory Ventilation in infants, to determine at what point Ventilation is being applied clinically, and to describe the relationship between airway pressure, lung volume, and oxygenation.Methods: In 12 infants, a partial inflation limb and the deflation limb of the pressure–volume relationship were mapped using a quasi-static lung volume optimization maneuver. This involved stepwise airway pressure increments to total lung capacity, followed by decrements until the closing pressure of the lung was identified.Measurements and Main Results: Lung volume and oxygen saturation were recorded at each airway pressure. Lung volume was measured using respiratory ...
-
Surfactant therapy for meconium aspiration syndrome: current status.
2005Co-Authors: Peter A. Dargaville, John F. MillsAbstract:Meconium aspiration syndrome (MAS) is an important cause of respiratory distress in the term infant. Therapy for the disease remains problematic, and newer treatments such as High-Frequency Ventilation and inhaled nitric oxide are being applied with increasing frequency. There is a significant disturbance of the pulmonary surfactant system in MAS, with a wealth of experimental data indicating that inhibition of surfactant function in the alveolar space is an important element of the pathophysiology of the disease. This inhibition may be mediated by meconium, plasma proteins, haemoglobin and oedema fluid, and, at least in vitro, can be overcome by increasing surfactant phospholipid concentration. These observations have served as the rationale for administration of exogenous surfactant preparations in MAS, initially as standard bolus therapy and, more recently, in association with therapeutic lung lavage. Bolus surfactant therapy in ventilated infants with MAS has been found to improve oxygenation in most studies, although there are a significant proportion of nonresponders and in many cases the effect is transient. Pooled data from randomised controlled trials of surfactant therapy suggest a benefit in terms of a reduction in the requirement for extracorporeal membrane oxygenation (relative risk 0.48 in surfactant-treated infants) but no diminution of air leak or ventilator days. Current evidence would support the use of bolus surfactant therapy on a case by case basis in nurseries with a relatively high mortality associated with MAS, or the lack of availability of other forms of respiratory support such as High-Frequency Ventilation or nitric oxide. If used, bolus surfactant should be administered as early as practicable to infants who exhibit significant parenchymal disease, at a phospholipid dose of at least 100 mg/kg, rapidly instilled into the trachea. Natural surfactant or a third-generation synthetic surfactant should be used and the dosage repeated every 6 hours until oxygenation has improved. Lung lavage with dilute surfactant has recently emerged as an alternative to bolus therapy in MAS, which has the advantage of removing surfactant inhibitors from the alveolar space in addition to augmenting surfactant phospholipid concentration. Combined animal and human data suggest that lung lavage can remove significant amounts of meconium and alveolar debris, and thereby improve oxygenation and pulmonary mechanics. Arterial oxygen saturation inevitably falls during lavage but has been noted to recover relatively rapidly, even in infants with severe disease. Several randomised controlled trials of surfactant lavage in MAS are underway, and until the results are known, lavage must be considered an unproven and experimental therapy.