Final answer:
The patient's symptoms including shortness of breath and low oxygen saturations despite oxygen therapy may indicate a serious condition like pulmonary embolism or exacerbation of pneumonia. A thorough reassessment and urgent medical intervention are necessary for stabilization.
Step-by-step explanation:
The sudden development of symptoms such as shortness of breath, restlessness, tachypnea, hemoptysis, and decreased oxygen saturations in a patient already receiving oxygen therapy can be suggestive of a serious underlying condition such as a pulmonary embolism, worsening pneumonia, or a heart failure exacerbation.
An important consideration is the patient's overall clinical presentation, including recent surgeries, immobility, or underlying conditions that may predispose to clots. In case of pneumonia, which appears likely given the history of a "shadow" in the lung and greenish sputum, the symptoms suggest a possible worsening of the pneumonia or a superimposed complication. It is crucial to act fast, reassess the patient, escalate the medical intervention, possibly including imaging studies like a CT scan or ventilation/perfusion (V/Q) scan, blood tests, and treatment adjustments such as increasing oxygen delivery and possibly initiating antibiotics if an infection is suspected. A comprehensive approach addressing the respiratory status, infection control, and supportive measures is essential for patient stabilization.