Measurement of static compliance of the total respiratory system in patients with acute respiratory failure during mechanical ventilation. The effect of intrinsic positive end-expiratory pressure

Patients with acute respiratory failure and decreased respiratory system compliance due to ARDS frequently present a formidable challenge. These patients are often subjected to high inspiratory pressure, and in severe cases in order to improve oxygenation and preserve life, we may need to resort to unconventional measures. The currently accepted ARDSNet guidelines are characterized by a generalized approach in which an algorithm for PEEP application and limited plateau pressure are applied to all mechanically ventilated patients. These guidelines do not make any distinction between patients, who may have different chest wall mechanics with diverse pathologies and different mechanical properties of their respiratory system. The ability of assessing pleural pressure by measuring esophageal pressure allows us to partition the respiratory system into its main components of lungs and chest wall. Thus, identifying the dominant factor affecting respiratory system may better direct and optimize mechanical ventilation. Instead of limiting inspiratory pressure by plateau pressure, PEEP and inspiratory pressure adjustment would be individualized specifically for each patient's lung compliance as indicated by transpulmonary pressure. The main goal of this approach is to specifically target transpulmonary pressure instead of plateau pressure, and therefore achieve the best lung compliance with the least transpulmonary pressure possible.

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Managing Persistent Hypoxemia: what is new?

F1000Research ◽

10.12688/f1000research.11760.1 ◽

2017 ◽

Vol 6 ◽

pp. 1993

Author(s):

Jesús Villar ◽

Carlos Ferrando ◽

Robert M Kacmarek

Keyword(s):

Mechanical Ventilation ◽

Respiratory Failure ◽

Acute Respiratory Failure ◽

Life Support ◽

Current Knowledge ◽

Positive End Expiratory Pressure ◽

Refractory Hypoxemia ◽

Standard Life ◽

Inspired Oxygen ◽

Review Current

Mechanical ventilation is the standard life-support technique for patients with severe acute respiratory failure. However, some patients develop persistent and refractory hypoxemia because their lungs are so severely damaged that they are unable to respond to the application of high inspired oxygen concentration and high levels of positive end-expiratory pressure. In this article, we review current knowledge on managing persistent hypoxemia in patients with injured lungs.

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Comparative study between noninvasive positive pressure ventilation and invasive mechanical ventilation in patients with respiratory failure

QJM ◽

10.1093/qjmed/hcab086.039 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Mohammed N Al Shafi'i ◽

Doaa M. Kamal El-din ◽

Mohammed A. Abdulnaiem Ismaiel ◽

Hesham M Abotiba

Keyword(s):

Intensive Care Unit ◽

Mechanical Ventilation ◽

Intensive Care ◽

Respiratory Failure ◽

Acute Respiratory Failure ◽

Positive Pressure Ventilation ◽

Invasive Mechanical Ventilation ◽

Noninvasive Positive Pressure Ventilation ◽

Positive Pressure ◽

Significant Difference

Abstract Background Noninvasive positive pressure ventilation (NIPPV) has been increasingly used in the management of respiratory failure in intensive care unit (ICU). Aim of the Work is to compare the efficacy and resource consumption of NIPPMV delivered through face mask against invasive mechanical ventilation (IMV) delivered by endotracheal tube in the management of patients with acute respiratory failure (ARF). Patients and Methods This prospective randomized controlled study included 78 adults with acute respiratory failure who were admitted to the intensive care unit. The enrolled patients were randomly allocated to receive either noninvasive ventilation or conventional mechanical ventilation (CMV). Results Severity of illness, measured by the simplified acute physiologic score 3 (SAPS 3), were comparable between the two patient groups with no significant difference between them. Both study groups showed a comparable steady improvement in PaO2:FiO2 values, indicating that NIPPV is as effective as CMV in improving the oxygenation of patients with ARF. The PaCO2 and pH values gradually improved in both groups during the 48 hours of ventilation. 12 hours after ventilation, NIPPMV group showed significantly more improvement in PaCO2 and pH than the CMV group. The respiratory acidosis was corrected in the NIPPV group after 24 hours of ventilation compared with 36 hours in the CMV group. NIPPV in this study was associated with a lower frequency of complications than CMV, including ventilator acquired pneumonia (VAP), sepsis, renal failure, pulmonary embolism, and pancreatitis. However, only VAP showed a statistically significant difference. Patients who underwent NIPPV in this study had lower mortality, and lower ventilation time and length of ICU stay, compared with patients on CMV. Intubation was required for less than a third of patients who initially underwent NIV. Conclusion Based on our study findings, NIPPV appears to be a potentially effective and safe therapeutic modality for managing patients with ARF.

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