Arterial Oxygenation during Artificial Ventilation. The Effect of Airway Closure and of Its Prevention by Positive End-Expiratory Pressure

Background In acute lung injury positive end-expiratory pressure (PEEP) and recruitment maneuver are proposed to optimize arterial oxygenation. The aim of the study was to evaluate the impact of such a strategy on lung histological inflammation and hyperinflation in pigs with acid aspiration-induced lung injury. Methods Forty-seven pigs were randomly allocated in seven groups: (1) controls spontaneously breathing; (2) without lung injury, PEEP 5 cm H2O; (3) without lung injury, PEEP titration; (4) without lung injury, PEEP titration + recruitment maneuver; (5) with lung injury, PEEP 5 cm H2O; (6) with lung injury, PEEP titration; and (7) with lung injury, PEEP titration + recruitment maneuver. Acute lung injury was induced by intratracheal instillation of hydrochloric acid. PEEP titration was performed by incremental and decremental PEEP from 5 to 20 cm H2O for optimizing arterial oxygenation. Three recruitment maneuvers (pressure of 40 cm H2O maintained for 20 s) were applied to the assigned groups at each PEEP level. Proportion of lung inflammation, hemorrhage, edema, and alveolar wall disruption were recorded on each histological field. Mean alveolar area was measured in the aerated lung regions. Results Acid aspiration increased mean alveolar area and produced alveolar wall disruption, lung edema, alveolar hemorrhage, and lung inflammation. PEEP titration significantly improved arterial oxygenation but simultaneously increased lung inflammation in juxta-diaphragmatic lung regions. Recruitment maneuver during PEEP titration did not induce additional increase in lung inflammation and alveolar hyperinflation. Conclusion In a porcine model of acid aspiration-induced lung injury, PEEP titration aimed at optimizing arterial oxygenation, substantially increased lung inflammation. Recruitment maneuvers further improved arterial oxygenation without additional effects on inflammation and hyperinflation.

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ARTIFICIAL VENTILATION IN HYALINE MEMBRANE DISEASE: THE USE OF POSITIVE END-EXPIRATORY PRESSURE AND CONTINUOUS POSITIVE AIRWAY PRESSURE

PEDIATRICS ◽

10.1542/peds.51.4.629 ◽

1973 ◽

Vol 51 (4) ◽

pp. 629-640

Author(s):

Niloufer Cumarasamy ◽

Rosmarie Nüssli ◽

Dieter Vischer ◽

Peter H. Dangel ◽

Gabriel V. Duc

Keyword(s):

Mechanical Ventilation ◽

Survival Rate ◽

Continuous Positive Airway Pressure ◽

Airway Pressure ◽

Positive Airway Pressure ◽

Artificial Ventilation ◽

Controlled Trial ◽

Hyaline Membrane Disease ◽

Positive End Expiratory Pressure ◽

Hyaline Membrane

During the years 1969, 1970, and 1971, 120 infants with hyaline membrane disease were studied, of whom 71 were treated with artificial ventilation. Among other changes in 1971, positive end-expiratory pressure was applied during mechanical ventilation and continuous positive airway pressure maintained during the weaning period. The survival rate of the ventilated babies increased from 23% in the preceding two years to 70% in 1971. As this study is not a controlled trial, the observed increase in survival cannot be ascribed to the application of increased airway pressure alone. The data presented, though necessarily inconclusive, may be useful for continuing comparisons with other pediatric centers.

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Lung and chest wall mechanics in patients with acute respiratory distress syndrome, expiratory flow limitation, and airway closure

Journal of Applied Physiology ◽

10.1152/japplphysiol.00059.2020 ◽

2020 ◽

Vol 128 (6) ◽

pp. 1594-1603 ◽

Cited By ~ 2

Author(s):

Claude Guérin ◽

Nicolas Terzi ◽

Louis-Marie Galerneau ◽

Mehdi Mezidi ◽

Hodane Yonis ◽

...

Keyword(s):

Mechanical Ventilation ◽

Distress Syndrome ◽

Flow Limitation ◽

Airway Closure ◽

Positive End Expiratory Pressure ◽

Expiratory Flow Limitation ◽

Lung Elastance ◽

Chest Wall Mechanics ◽

Expiratory Flow ◽

Better Than

Expiratory flow limitation (EFL) and airway closure (AC) were observed in 32% and 52%, respectively, of 25 patients with ARDS investigated during mechanical ventilation in supine position with a positive end-expiratory pressure of 5 cmH2O. The performance of dynamic lung elastance to detect expiratory flow limitation was good and better than that to detect airway closure. The vast majority of patients with EFL also had AC; however, AC can occur in the absence of EFL.

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Animal Experiments on the Effects of PEEP and Different Ventilation-Compression Ratios in Neonatal Cardiopulmonary Resuscitation

Prehospital and Disaster Medicine ◽

10.1017/s1049023x00044526 ◽

1985 ◽

Vol 1 (S1) ◽

pp. 214-215

Author(s):

W. F. Dick ◽

E. Traub ◽

K. Engels ◽

K. -H. Lindner

Keyword(s):

Body Weight ◽

Cardiac Arrest ◽

Artificial Ventilation ◽

Animal Experiments ◽

Ventilation Rate ◽

Positive End Expiratory Pressure ◽

Cardiac Compression ◽

Ventilation Rates ◽

Average Body ◽

Average Body Weight

The physiological range of respiratory rates and heart rates in neonates is approximately 40 per min and 120 per min, respectively, which yields a theoretical ventilation-compression ratio of 1:3ratherthan 1:5.Thirty-six anesthetized pigs with an average body weight of 4–5 kg were used in the study. After establishing a steady state by artificial ventilation with 100% oxygen, a cardiac arrest was induced by an intravenous injection of potassium chloride. Following the cardiac arrest, the animals were resuscitated with ventilation rates of 30 and 40 per min, respectively, while external cardiac compression was performed at rates between 60 and 160 per min. Randomly selected animals were resuscitated with ventilation-compression ratios of 1:2, 1:3 and 1:4 for 10 min each, 6 animals each were ventilated using a ventilation rate of 30 per min, 40 per min, or positive end-expiratory pressure.

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Mechanical ventilation with positive end-expiratory pressure preserves arterial oxygenation during prolonged pneumoperitoneum

Surgical Endoscopy ◽

10.1007/s00464-001-8174-y ◽

2002 ◽

Vol 16 (4) ◽

pp. 685-689 ◽

Cited By ~ 27

Author(s):

E. J. Hazebroek ◽

J. J. Haitsma ◽

B. Lachmann ◽

H. J. Bonjer

Keyword(s):

Mechanical Ventilation ◽

Arterial Oxygenation ◽

Positive End Expiratory Pressure

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Severe Fat Embolism: A Review of 24 Cases

Scottish Medical Journal ◽

10.1177/003693307802300208 ◽

1978 ◽

Vol 23 (2) ◽

pp. 141-148 ◽

Cited By ~ 4

Author(s):

J. A. W. Wildsmith ◽

A. H. B. Masson

Keyword(s):

Poor Prognosis ◽

Oxygen Therapy ◽

Artificial Ventilation ◽

Supportive Therapy ◽

Fat Embolism ◽

Heparin Therapy ◽

Arterial Oxygenation ◽

Embolism Syndrome ◽

Severity Of Injury ◽

The Many

Twenty-four patients suffering from fat embolism syndrome, severe enough to warrant transfer to an artificial ventilation unit, are reviewed. All developed the condition following trauma. Five patients were managed with oxygen therapy and sedation, but the other 19 needed intubation and ventilation to achieve adequate arterial oxygenation. In spite of intensive supportive therapy, 6 patients (who had all required ventilation) died, one due to heparin therapy, the others from progression of the syndrome. A poor prognosis seemed to be associated with young age, a rapidly progressive condition and a continued need for 100 per cent oxygen after institution of artificial ventilation. There seemed to be no relationship between outcome and severity of injury, type of surgical management and time of onset after injury. The clinical features of these patients are discussed with reference to the many unanswered questions that surround this condition.

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