A 75-year-old male with known chronic heart failure presents with worsening breathlessness over 3 days. He is now orthopnoeic, has bilateral basal crackles, elevated JVP, and peripheral oedema. His blood pressure is 95/60 mmHg. SpO2 is 88% on air. What is the key difference in management compared to the hypertensive pulmonary oedema scenario?