Secondary outcome measures are oral tracheal intubation time , days alive outside the intensive care unit , days alive outside the hospital , and 30 - and 90-day mortality , and one or more of the following selected serious adverse events : pneumothorax or pleural effusion requiring drainage , major bleeding , reoperation , severe infection , cerebral event , hyperkaliemia , acute myocardial infarction , cardiac arrhythmia , renal replacement therapy , and readmission for a respiratory-related problem .