A 68-year-old man is scheduled for an elective anterior cervical decompression and fusion due to a progressive cervical radiculopathy with numbness and pain in the C6 distribution bilaterally. He has stable coronary artery disease with Class II angina and well-controlled type 2 diabetes mellitus. He is a nonsmoker and has no history of sleep apnea. He has no allergies and he is taking metoprolol, amlodipine, glyburide, and is on a nitroglycerine patch.
His chest is clear and heart sounds are normal. His airway examination reveals that he is edentulous with a full beard. He has a Mallampati Class II pharyngeal view, a 6.0 cm thyromental distance, and 4.0 cm of mouth opening. There is a slight reduction of neck extension (approximately 30 degrees). He is 170 cm tall (5 ft 7 in), and weighs 110 kg (242 lb) with a BMI 38 kg·m−2. His vital signs are: blood pressure (BP) 140/95 mm Hg, heart rate (HR) 64 beats per minute (bpm), respiratory rate (RR) 20 breaths per minute, SpO2 95% on room air.
Laboratory investigations reveal normal CBC, electrolytes, and creatinine. The random blood glucose is 7.1 mmol·L−1. He has a normal ECG. An MRI of the cervical spine shows disc protrusion at the C4-5 and C5-6 levels causing nerve root compression at the C6 level bilaterally and CSF effacement in front of C4-5 and C5-6 levels without signal changes in the spinal cord.
A diagnosis of cervical radiculopathy has been made.
40.2.1 What Are the Anesthetic Considerations for a Morbidly Obese Patient with a BMI of 38?
Morbid obesity is associated with a number of anatomic, physiologic, and biochemical changes (see also Chapter 18).1 The cardiovascular system of obese patients is characterized by increased cardiac output, increased circulatory blood volume, and an increased incidence of systemic hypertension and coronary artery disease. In the respiratory system, they have increased oxygen consumption, increased carbon dioxide production, reduced functional residual capacity, increased premature airway closure and shunt, decreased chest wall compliance, and increased work of breathing. There is an increased incidence of pulmonary hypertension and obstructive sleep apnea. There is also a higher incidence of hiatus hernia, gastroesophageal reflux, glucose intolerance, and diabetes mellitus. Airway considerations are detailed later.
40.2.2 Is This Patient at an Increased Risk of Having a Perioperative Cardiac Event?
Yes. This patient has several risk factors and is at a higher risk of having a perioperative cardiac event. There are several well-established perioperative cardiac risk assessment tools. He has diabetes and stable, functional Class II angina which according to the 2007 ACC/AHA guidelines2,3 are two clinical risk factors. Utilizing the Lee cardiac risk score,4 he has two (CAD and diabetes) of six risk factors and is predicted to have a perioperative cardiac event rate of approximately 5%. Utilization of perioperative beta-blockade ...