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Lung Ventilation (lung + ventilation)
Kinds of Lung Ventilation Selected AbstractsAn Evaluation of a Blind Rotational Technique for Selective Mainstem IntubationACADEMIC EMERGENCY MEDICINE, Issue 10 2004Aaron E. Bair MD Abstract Objectives: Although rare, massive hemoptysis and major bronchial disruptions are associated with high mortality. Selective ventilation of the uninvolved lung can increase the likelihood of survival. Specialized devices used for single lung ventilation are often not readily available and can be difficult to place in the emergency department. The authors evaluated a blind rotational technique for selective mainstem intubation using either a standard endotracheal tube (ET) or a directional-tip endotracheal tube (DTET). Methods: This was a prospective, randomized trial on 25 human cadavers. The desired side of mainstem intubation was determined by randomization. Each cadaver was used for four ET, four DTET, and four control intubations. In the ET group, the trachea was intubated. The tube was then rotated 90° in the direction of the desired placement and advanced until resistance was met. In the DTET group, the technique was identical, except the trigger was activated to flex the tip during advancement. In the control group, an ET was advanced in neutral alignment until resistance was met. A bronchoscopist blinded to the desired placement determined tube position. Comparison testing was performed using Pearson's chi-square test. Results: When attempting to intubate the left mainstem, use of the ET with the rotational technique was successful 72.3% of the time (95% confidence interval [95% CI] = 57% to 84%). Intubation of the left mainstem using the DTET was successful 68.5% of the time (95% CI = 54% to 81%; p = 0.67). Attempts to selectively intubate the right mainstem using the rotational technique were highly successful in both groups: 94% for the ET (95% CI = 84% to 99%) versus 97.8% for the DTET (95% CI = 89% to 100%). Among controls, the right mainstem was intubated 93% of the time (95% CI = 86% to 97%). Conclusions: In a cadaveric model, the left mainstem bronchus can be selectively intubated with moderate reliability using this rotational technique. Use of a DTET confers no significant advantage. The ability to generalize these findings to living subjects is unknown. [source] Gravity is an important determinant of oxygenation during one-lung ventilationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2010L. L. SZEGEDI Background: The role of gravity in the redistribution of pulmonary blood flow during one-lung ventilation (OLV) has been questioned recently. To address this controversial but clinically important issue, we used an experimental approach that allowed us to differentiate the effects of gravity from the effects of hypoxic pulmonary vasoconstriction (HPV) on arterial oxygenation during OLV in patients scheduled for thoracic surgery. Methods: Forty patients with chronic obstructive pulmonary disease scheduled for right lung tumour resection were randomized to undergo dependent (left) one-lung ventilation (D-OLV; n=20) or non-dependent (right) one-lung ventilation (ND-OLV; n=20) in the supine and left lateral positions. Partial pressure of arterial oxygen (PaO2) was measured as a surrogate for ventilation/perfusion matching. Patients were studied before surgery under closed chest conditions. Results: When compared with bilateral lung ventilation, both D-OLV and ND-OLV caused a significant and equal decrease in PaO2 in the supine position. However, D-OLV in the lateral position was associated with a higher PaO2 as compared with the supine position [274.2 (77.6) vs. 181.9 (68.3) mmHg, P<0.01, analysis of variance (ANOVA)]. In contrast, in patients undergoing ND-OLV, PaO2 was always lower in the lateral as compared with the supine position [105.3 (63.2) vs. 187 (63.1) mmHg, P<0.01, ANOVA]. Conclusion: The relative position of the ventilated vs. the non-ventilated lung markedly affects arterial oxygenation during OLV. These data suggest that gravity affects ventilation,perfusion matching independent of HPV. [source] Effects of restricted thoracic movement on the regional distribution of ventilationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2010S. PULLETZ Background: Restricted thoracic movement is often encountered in patients, necessitating mechanical ventilation during surgery or intensive care treatment. High intraabdominal pressure, obesity or thorax rigidity and deformity reduce the chest distensibility and deteriorate the lung function. They render the selection of proper ventilator settings difficult and complicate the weaning process. Electrical impedance tomography (EIT) is currently being proposed as a bedside imaging method for monitoring regional lung ventilation. The objective of our study was to establish whether the effects of decreased chest compliance on regional lung ventilation can be determined by EIT. Methods: Ten healthy male volunteers were studied in our pilot study under three conditions: (1) unrestricted breathing and (2) restricted breathing by abdominal and (3) lower rib cage strapping. The subjects were followed during spontaneous tidal breathing in five postures (sitting, supine, prone, left and right side). EIT and spirometry data were acquired in each condition. Results: The distribution of ventilation in subjects with unrestricted breathing corresponded with the physiologically expected values. In the left and right lateral postures, abdominal and thoracic cage restrictions reduced the ventilation in the dependent lung areas; the non-dependent areas were unaffected. In the prone position, the ventilation of the dependent and non-dependent areas was reduced. The effects of strapping were least pronounced in the supine posture. Conclusions: We conclude that EIT is able to measure changes in the regional distribution of ventilation induced by restricted chest movement and has the potential for optimising artificial ventilation in patients with limited chest compliance of different origins. [source] Hepatic effects of an open lung strategy and cardiac output restoration in an experimental lung injuryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2010M. KREDEL Background: Ventilation with high positive end-expiratory pressure (PEEP) can lead to liver dysfunction. We hypothesized that an open lung concept (OLC) using high PEEP impairs liver function and integrity dependent on the stabilization of cardiac output. Methods: Juvenile female Pietrain pigs instrumented with flow probes around the common hepatic artery and portal vein, pulmonary and hepatic vein catheters underwent a lavage-induced lung injury. Ventilation was continued with a conventional approach (CON) using pre-defined combinations of PEEP and inspiratory oxygen fraction or with an OLC using PEEP set above the lower inflection point of the lung. Volume replacement with colloids was guided to maintain cardiac output in the CON(V+) and OLC(V+) groups or acceptable blood pressure and heart rate in the OLC(V,) group. Indocyanine green plasma disappearance rate (ICG-PDR), blood gases, liver-specific serum enzymes, bilirubin, hyaluronic acid and lactate were tested. Finally, liver tissue was examined for neutrophil accumulation, TUNEL staining, caspase-3 activity and heat shock protein 70 mRNA expression. Results: Hepatic venous oxygen saturation was reduced to 18 ± 16% in the OLC(V,) group, while portal venous blood flow decreased by 45%. ICG-PDR was not reduced and serum enzymes, bilirubin and lactate were not elevated. Liver cell apoptosis was negligible. Liver sinusoids in the OLC(V+) and OLC(V,) groups showed about two- and fourfold more granulocytes than the CON(V+) group. Heat shock protein 70 tended to be higher in the OLC(V,) group. Conclusions: Open lung ventilation elicited neutrophil infiltration, but no liver dysfunction even without the stabilization of cardiac output. [source] Effects of ozone exposure in rat lungs investigated with hyperpolarized 3He MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2008Yannick Crémillieux PhD Abstract Purpose To investigate the effects of subchronic ozone exposure on rat lung ventilation using hyperpolarized (HP) 3He MRI. Materials and Methods A total of 24 Sprague-Dawley rats, distributed in one control group and four groups exposed to 0.5 ppm ozone concentration for two days or six days, either continuously (22 hours/day) or alternatingly (12 hours/day). A three-step MRI protocol was designed and applied to each animal, including: 1) 3He gas distribution images acquired at inspiratory capacity, 2) measurements of intrapulmonary 3He diffusion coefficients, and 3) dynamic ventilation acquisitions performed during lung filling with 3He. Results No differentiation between animals exposed to ozone and control animals was observed from the ventilation images obtained at inspiratory capacity. The 3He diffusion coefficients were not statistically different from one group to another. Ventilation defects, appearing as delayed lung filling regions and heterogeneous lung filling, were observed in the dynamic lung ventilation image series. The percentage of animals with ventilation defects in the control, two-day, and six-day exposed groups were equal to 20%, 43% and 75%, respectively. In the subgroup of the animals exposed six days for 12 hours per day, the percentage of animals exhibiting ventilation defects was equal to 85%. Conclusion Heterogeneous obstructive patterns in an experimental animal model of subchronic ozone exposure were observed using HP 3He MRI. J. Magn. Reson. Imaging 2008;27:771,776. © 2008 Wiley-Liss, Inc. [source] Rapid and efficient mapping of regional ventilation in the rat lung using hyperpolarized 3He with Flip angle variation for offset of RF and relaxation (FAVOR)MAGNETIC RESONANCE IN MEDICINE, Issue 6 2008Giles E. Santyr Abstract A novel imaging method is presented, Flip Angle Variation for Offset of RF and Relaxation (FAVOR), for rapid and efficient measurement of rat lung ventilation using hyperpolarized helium-3 (3He) gas. The FAVOR technique utilizes variable flip angles to remove the cumulative effect of RF pulses and T1 relaxation on the hyperpolarized gas signal and thereby eliminates the need for intervening air wash-out breaths and multiple cycles of 3He wash-in breaths before each image. The former allows an improvement in speed (by a factor of ,30) while the latter reduces the cost of each measurement (by a factor of ,5). The FAVOR and conventional ventilation methods were performed on six healthy male Brown Norway rats (190,270 g). Lobar measurements of ventilation, r, obtained with the FAVOR method were not significantly different from those obtained with the conventional method for the right middle and caudal and left lobes (P > 0.05 by a Wilcoxon matched pairs test). A methacholine challenge test was also administered to an animal and reduction and recovery of r was detected by the FAVOR method. The reduced 3He consumption and the improvement in speed provided by FAVOR suggest that it may allow measurement of ventilation in human subjects not previously possible. Magn Reson Med 59:1304,1310, 2008. © 2008 Wiley-Liss, Inc. [source] Assessment and compensation of susceptibility artifacts in gradient echo MRI of hyperpolarized 3He gasMAGNETIC RESONANCE IN MEDICINE, Issue 2 2003Jim M. Wild Abstract The effects of macroscopic background field gradients upon 2D gradient echo images of inhaled 3He in the human lung were investigated at 1.5 T. Effective compensation of in-slice signal loss in 3He gradient echo images was then demonstrated using a multiple acquisition interleaved single gradient echo sequence. This method restores signal dephasing through a combination of separate images acquired with different slice refocusing gradients. In vivo imaging of volunteers with the sequence shows substantial restoration of signal at the lung periphery and close to blood vessels. The technique presented may be useful when using 3He MRI for volumetric measurements of lung ventilation and in studies using 3He combined with intravenous contrast as a means of assessing lung ventilation/perfusion (V/Q). Magn Reson Med 50:417,422, 2003. © 2003 Wiley-Liss, Inc. [source] Hay,Wells syndrome (AEC): a case reportORAL DISEASES, Issue 5 2006Emilio Macias We would like to present a case of the rare genetic skin disorder catalogued as AEC syndrome. This rare disorder was described in 1976 by Hay and Wells in seven individuals from four families, and it entails a complex polymalformative syndrome with an autosomal-dominant inheritance pattern and variable penetration. Descriptive explanation and facial and intraoral images of this rare disorder constituted the study design. The neonatal report outlines dysplastic phenotype, micrognathia, hypoplasia of the hard and soft palate, cleft palate, small nose, mammary hypoplasia with ectopic mammary nodules, hypoplastic external genitalia with clitoral hypertrophy, hypoplasia of the nails, a tendency towards dorsiflexion of the big toe on both feet, ankyloblepharon filiforme, low positioning of the auricles and faulty development of the left auricle, scaly exanthema with eritrodermatitis and hyperkeratosis, good lung ventilation, normal heart rhythm and normal neurological examination. Although only a few cases published are available, clinical variability is one of the hallmarks of AEC syndrome. The majority of authors consider ankyloblepharon, ectodermal dysplasia and orofacial clefting as cardinal signs. They are all are present in the case reported. [source] Protective ventilation to reduce inflammatory injury from one lung ventilation in a piglet modelPEDIATRIC ANESTHESIA, Issue 4 2010MARY C. THEROUX MD Summary Objectives:, To test the hypothesis that protective ventilation strategy (PVS) as defined by the use of low stretch ventilation (tidal volume of 5 ml·kg,1 and employing 5 cm of positive end expiratory pressure (PEEP) during one lung ventilation (OLV) in piglets would result in reduced injury compared to a control group of piglets who received the conventional ventilation (tidal volume of 10 ml·kg,1 and no PEEP). Background:, PVS has been found to be beneficial in adults to minimize injury from OLV. We designed the current study to test the beneficial effects of PVS in a piglet model of OLV. Methods:, Ten piglets each were assigned to either ,Control' group (tidal volume of 10 ml·kg,1 and no PEEP) or ,PVS' group (tidal volume of 5 ml·kg,1 during the OLV phase and PEEP of 5 cm of H2O throughout the study). Experiment consisted of 30 min of baseline ventilation, 3 h of OLV, and again 30 min of bilateral ventilation. Respiratory parameters and proinflammatory markers were measured as outcome. Results:, There was no difference in PaO2 between groups. PaCO2 (P < 0.01) and ventilatory rate (P < 0.01) were higher at 1.5 h OLV and at the end point in the PVS group. Peak inflating pressure (PIP) and pulmonary resistance were higher (P < 0.05) in the control group at 1.5 h OLV. tumor necrosis factor-alpha (P < 0.04) and IL-8 were less (P < 0.001) in the plasma from the PVS group, while IL-6 and IL-8 were less (P < 0.04) in the lung tissue from ventilated lungs in the PVS group. Conclusions:, Based on this model, PVS decreases inflammatory injury both systemically and in the lung tissue with no adverse effect on oxygenation, ventilation, or lung function. [source] Differential lung ventilation in infants and children with pulmonary hyperinflationPEDIATRIC ANESTHESIA, Issue 5 2003Gregory B. Hammer MD No abstract is available for this article. [source] Single lung ventilation in children using a new paediatric bronchial blockerPEDIATRIC ANESTHESIA, Issue 1 2002GREGORY B HAMMER MD As video-assisted thoracoscopic surgery has become more common in paediatric patients, the use of single lung ventilation in children has also increased. Single lung ventilation in young children is performed by either advancing a tracheal tube into the mainstem bronchus opposite the side of surgery or by positioning a bronchial blocker into the mainstem bronchus on the operative side. Techniques for placing a variety of bronchial blockers outside the tracheal tube have been described. We describe a technique for placement of a new bronchial blocker through an indwelling tracheal tube using a multiport adaptor and a fibreoptic bronchoscope. [source] Lung Function Tests in Neonates and Infants with Chronic Lung Disease: Global and Regional Ventilation InhomogeneityPEDIATRIC PULMONOLOGY, Issue 2 2006J. Jane Pillow FRACP Abstract This review considers measurement of global and regional ventilation inhomogeneity (VI) in infants and young children with acute neonatal respiratory disorders and chronic lung disease of infancy (CLDI). We focus primarily on multiple-breath inert gas washout (MBW) and electrical impedance tomography (EIT). The literature is critically reviewed and the relevant methods, equipment, and studies are summarized, including the limitations and strengths of individual techniques, together with the availability and appropriateness of any reference data. There has been a recent resurgence of interest in using MBW to monitor lung function within individuals and between different groups. In the mechanically ventilated, sedated, and paralyzed patient, VI indices can identify serial changes occurring following exogenous surfactant. Similarly, global VI indices appear to be increased in infants with CLDI and to differentiate between infants without lung disease and those with mild, moderate, and severe lung disease following preterm birth. While EIT is a relatively new technique, recent studies suggest that it is feasible in newborn infants, and can quantitatively identify changes in regional lung ventilation following alterations to ventilator settings, positive end expiratory pressure (PEEP), and administration of treatments such as surfactant. As such, EIT represents one of the more exciting prospects for continuous bedside pulmonary monitoring. For both techniques, there is an urgent need to establish guidelines regarding data collection, analysis, and interpretation in infants both with and without CLDI. © 2005 Wiley-Liss, Inc. [source] Severe Legionella pneumonia successfully treated by independent lung ventilation with intrapulmonary percussive ventilationRESPIROLOGY, Issue 3 2008Motoki FUJITA Abstract: A case of severe Legionella pneumonia was successfully treated by independent lung ventilation (ILV) with intrapulmonary percussive ventilation (IPV). A 57-year-old man with lobar pneumonia was intubated and mechanically ventilated because of his deteriorating respiratory status. The diagnosis of Legionella pneumonia was made on the fourth day after admission and appropriate antibiotic therapy was commenced. On the fifth hospital day, ILV was commenced because the right unaffected lung was over-distended, his haemodynamic state was unstable and his left lung was producing copious amounts of purulent sputum. His right lung was ventilated and his left lung was treated with IPV owing to the existence of massive atelectasis. After treatment with antibiotics and ILV combined with IPV, his respiratory and haemodynamic status gradually improved. On the tenth day after admission, ILV was changed to conventional bilateral ventilation. The patient was extubated on the sixteenth hospital day and discharged from the intensive care unit 30 days after admission. The combination of ILV and IPV was therapeutically effective during the acute phase of unilateral severe Legionella pneumonia. [source] Pumpless extracorporeal removal of carbon dioxide combined with ventilation using low tidal volume and high positive end-expiratory pressure in a patient with severe acute respiratory distress syndromeANAESTHESIA, Issue 2 2009T. Bein Summary The effects of the combination of a ,lowest' lung ventilation with extracorporeal elimination of carbon dioxide by interventional lung assist are described in a patient presenting with severe acute respiratory distress syndrome due to fulminant pneumonia. Reducing tidal volume to 3 ml.kg,1 together with interventional lung assist resulted in a decrease in severe hypercapnia without alveolar collapse or hypoxaemia but with a decrease in serum levels of interleukin-6. This approach was applied for 12 days with recovery of the patient, without complications. Extracorporeal removal of carbon dioxide by interventional lung assist may be a useful tool to enable ,ultraprotective' ventilation in severe acute respiratory distress syndrome. [source] A comparison of the intubating laryngeal mask airway and the Bonfils intubation fibrescope in patients with predicted difficult airways,ANAESTHESIA, Issue 7 2004B. Bein Summary Tracheal intubation with the intubating laryngeal mask airway or the Bonfils intubation fibrescope was performed in 80 patients with predicted difficult airways. Mallampati score, thyromental distance, mouth opening and mobility of the atlanto-occipital joint were used to predict difficult airways. The overall success rate, time to the first adequate lung ventilation and time taken for the successful placement of the tracheal tube were recorded, as well as a subjective assessment of the handling of the device and the incidence of postoperative sore throat and hoarseness. The median [range] time to the first adequate ventilation was significantly shorter with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (28 [6,85] s vs. 40 [23,77] s, p < 0.005). Tracheal intubation was significantly slower with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (76 [45,155] s vs. 40 [23,77] s, p < 0.0001. Patients in the Bonfils group suffered less sore throat and hoarseness than those in the other group. [source] Use of the `T,bag' oxygen enhancement device to improve oxygenation during single lung ventilationANAESTHESIA, Issue 7 2002K. Hames No abstract is available for this article. [source] | |||||||||||||||||||||||||