In obese animals, which respiratory change is likely under anesthesia?

In obese animals, which respiratory change is likely under anesthesia?

• A. Hypercapnia
• B. Hypoxemia
• C. Hyperglycemia
• D. Hyperkalemia

Answer: (A)

In obesity, the lungs are more prone to retaining carbon dioxide when you anesthesia-suppress breathing. Obesity reduces functional residual capacity and chest wall compliance, and anesthesia further depresses the drive to breathe while lowering tidal volume. The diaphragm is pushed upward by abdominal fat, promoting airway closure and atelectasis, especially in dependent lung regions. All together, these changes reduce overall ventilation, so CO2 isn’t cleared efficiently and arterial CO2 rises—hypercapnia. Oxygen levels can drop too (hypoxemia) from V/Q mismatch, but the hallmark respiratory change here is CO2 retention due to hypoventilation. Hyperglycemia and hyperkalemia aren’t primary respiratory effects of anesthesia in obesity. Monitoring with capnography and providing strategies like appropriate ventilator settings and PEEP can help mitigate hypercapnia.

In obesity, the lungs are more prone to retaining carbon dioxide when you anesthesia-suppress breathing. Obesity reduces functional residual capacity and chest wall compliance, and anesthesia further depresses the drive to breathe while lowering tidal volume. The diaphragm is pushed upward by abdominal fat, promoting airway closure and atelectasis, especially in dependent lung regions. All together, these changes reduce overall ventilation, so CO2 isn’t cleared efficiently and arterial CO2 rises—hypercapnia. Oxygen levels can drop too (hypoxemia) from V/Q mismatch, but the hallmark respiratory change here is CO2 retention due to hypoventilation. Hyperglycemia and hyperkalemia aren’t primary respiratory effects of anesthesia in obesity. Monitoring with capnography and providing strategies like appropriate ventilator settings and PEEP can help mitigate hypercapnia.