Tetraplegia After Coronary Artery Bypass Grafting in a Patient with Undiagnosed Cervical Stenosis

Abstract

To the Editor: We read with great interest the case report of Fujioka et al. (1), who attributed the tetraplegia after coronary artery bypass grafting (CABG) to the perioperative extension of the neck in a patient with preexisting cervical spine stenosis. We report a second case of tetraplegia after CABG in a patient with undiagnosed cervical stenosis. A 61-yr-old man who developed acute myocardial infarction that was stabilized by streptokinase followed, after 10 days, by coronary artery bypass grafting. The preoperative neurological examination did not reveal any neurological complaint or abnormalities. The patient was monitored with an electrocardiogram, arterial blood pressure, saturation, a radial artery, and cannulation, and a pulmonary artery catheter was inserted. Anesthesia was induced with midazolam, propofol, fentanyl, and vecuronium, to be followed by easy orotracheal intubation. Thereafter, the patient’s neck was placed in an extension position. Cardiopulmonary bypass (CPB) was initiated after heparinization, and coronary artery bypass grafting of 4 vessels was performed. During CPB, the patient was perfused by a roller pump at a flow rate of 2.4 U · min/m2. The mean body temperature was maintained between 32°C–34°C and the mean blood pressure was maintained at 60–70 mm Hg. When surgery was completed after 4 h, the aortic cross-clamp was released, and the patient was rewarmed to a body temperature of 37°C. The weaning from cardiopulmonary bypass was successful. Heparinization was reversed with protamine and the patient was transferred to the intensive cardiac care unit. The patient awoke 6 h later, and the trachea was extubated. However, the patient was unable to move any of his four limbs. Neurological examination revealed complete paralysis of his four limbs associated with loss of sensation. An urgent cervical magnetic resonance imaging scan revealed a congenital cervical stenosis extending from C3 to C6, associated with a posterior disk herniation at C6-C7 compressing the cervical cord, which was focally edematous (Fig. 1). Immediately, an anterior surgical decompression with spinal instrumentation was performed (Fig. 2). After the operation, neurological examination showed a significant improvement and revealed a partial brown squared syndrome. Urinary and anal incontinence were also recorded. Six weeks later, the patient left the hospital. However, 3 mo later the patient died from bowel perforation and respiratory failure. The present report agrees with the previous report of Fujioka et al. (1), who speculated that placing the neck in an extended position during surgery might aggravate a preexisting spinal canal stenosis, resulting in cervical cord injury. Also, this report suggests that we should avoid extending the neck in patients with a preoperative diagnosis of cervical spine stenosis and that the neck should be manipulated similarly to manipulation of patients with cervical spine fracture. Also, preoperative screening for cervical spine stenosis is advised for elderly patients in whom an extended position of the neck is required.Figure 1.: Preoperative magnetic resonance image scan. Arrows = preoperative magnetic resonance image scan showing C5-C6 stenosis.Figure 2.: Postoperative magnetic resonance image scan. Arrows = postoperative magnetic resonance image scan showing site of C6 corpectomy. C4-C5, C5-C6, discectomy with bone graft and Codman plat®, and screws.Zoher Naja, MD* [email protected] Ahed Zeidan, MD† Hilal Maaliki, MD† Samir Zoubeir, MD‡ R. El-Khatib, MD* Anis Baraka, MD, FRCA** Departments of *Anesthesiology and ‡Neurosurgery, Makassed General Hospital, †Department of Anesthesiology, Sahel General Hospital, and **Department of Anesthesiology, American University of Beirut Medical Center, Beirut, Lebanon