A 55-year-old woman was admitted to the intensive care unit with severe lobar pneumonia and septic shock. She remained hypoxemic despite intubation, a high fraction of inspired oxygen, and positive end-expiratory pressure (PEEP). When PEEP was increased further, she paradoxically became more hypoxemic and her blood pressure and central venous hemoglobin saturation fell. What would be your approach
High levels of PEEP can decrease cardiac output and tissue oxygen delivery with subsequent decreases in mixed and central venous oxygen content that contribute to impaired arterial oxygenation in patients with increased shunt fractions. So in this patient give dobutamine to correct hypotension and reduce PEEP so as to increase oxygenation.
Keep PEEP at the highest and give adrenaline
Initiate dobutamine and reduce PEEP to 5cm H2O
Increase PEEP further
Increase FiO2