What Are The Advantages And Disadvantages Of Inverse Ratio Ventilation

Inverse ratio ventilation

• Interdiction about Inverse ratio ventilation (IRV)

• Pressure Controlled Inverse Ratio Ventilation (PC - IRV)

• airway pressure release ventilation (APRV)

• permissive hypercapnia (PHY)

• Advantage and disadvantage of (IRV)

• concluding Introduction of (IRV):

It is prepared to recruit alveolar units through extending of the inspiratory phase of the ventilatory cycle, shorting of the expiratory phase of the ventilatory cycle and improve oxygenation in patients how had acute respiratory distress syndrome and acute lung injury (ALI / ARDS), (IRV) characterized by increased inspiratory time on the ventilator is prolonged so that I: E ratio is inversed and may exceed (1: 1, 2: 1, 3: 1, 4: 1). (1) Trauma book Gurkin,

(PC - IRV) suggested for severe hypoxemia when high positive end expiratory pressure (PEEP) and high FiO2 have failed to improve oxygenation in (ALI / ARDS) (ega). The result is maintenance of numerous alveoli open and intrinsic Positive end expiratory pressure (PEEP), improving arterial oxygenation (Bates). (IRV ) with low (PEEP) levels during conventional ventilation, (IRV) is successful in improving Pao2, moderate PEEP levels that prevent recruitment, and when use high PEEP levels are required in severe ARDS, oxygenation is better preserved with conventional ventilation due to a lower shunt (Ferrando).The study’s by (Chaco): the three randomized trials compared pressure control ventilation (PCV) versus volume control ventilation (VCV) in a total of 1089 adults with (ALI / ARDS) from 43 intensive care unit (ICU).The method was they use (PC-IRV),equivalent pressure-controlled model compared with (VCV), we included parallel-group randomized controlled trials (RCTs) and quasi-RCTs irrespective of their language or publication status. Primary outcomes are 1- In-hospital mortality, including ICU mortality2- Mortality at 28 days. The result was 1-(PCV) probably reduces ICU mortality of (ALI / ARDS) compared with (VCV), 2- Risk of barotrauma may not differ between (PCV) and (VCV). There is some studies have shown

(APRV) generally features two levels of (PEEP): a low (PEEP) that is usually set to zero and a high (PEEP) often set to approximately 25 to 30 cmH2O and (APRV) is similar to (IRV) extending the inspiratory phase of the ventilator cycle with inspiratory times often of 4 to 6 seconds at the high (PEEP) level (egns).The major advantages of (APRV) potential lung-protective benefits, preservation of spontaneous unassisted ventilation throughout the entire ventilatory cycle and maintenance of relatively long inflation time (Daoud). The benefit of Spontaneous breathing by improved of lung recruitment, ventilation of dependent lung zones, resulting in improved (V /Q) matching with decreased shunt (Neumann). Peak inspiration pressures (PIP) during APRV may be less than with Volume control Inverse ratio ventilation (VC – IRV) for comparable oxygenation and ventilation (Davis). The study by (Putensen): Thirty patients with multiple trauma were randomly assigned to either breathe spontaneously with (APRV) (APRV Group n = 15) and (PCV Group n = 15). Method