My mother's oxygen level decreases as she sleeps. Doctors say that when she breath lungs do not throw back oxygen out. Her age is 67 years, weight is 95kg and height 5 feet. Please suggest.

Your mother's condition, known as sleep-related hypoxemia, may be related to obesity-hypoventilation syndrome (OHS) or sleep apnea, given her weight and age; consider consulting a pulmonologist or sleep specialist for a thorough evaluation, including a sleep study, and potential treatments like continuous positive airway pressure (CPAP) therapy, oxygen supplementation, or weight loss strategies to improve her oxygen levels and overall health.