Severe Decrease in Lung Compliance During a Code Blue

An 80-yr-old, 90 kg, 5′7″ male with a past medical history of coronary artery disease, diabetes mellitus, right inguinal hernia, hypertension, chronic obstructive pulmonary disease, and end-stage renal disease requiring hemodialysis is admitted to an intermediate ICU with upper gastrointestinal bleeding. He is conscious, pale, cold, and clammy. Because he complains of being cold, he is covered with several blankets. His BP is 90/40 and his heart rate is 120 sinus. His hematocrit is 20 and he is transfused with 3 units of packed red blood cells over a 40-min period. After this, he becomes unresponsive, with very weak respiratory efforts. A one-stick radial arterial blood gas shows pH 6.9, pCO2 107, and paO2 53 on a 100% O₂ nonrebreather mask?