Bilateral vocal cord paralysis following coronary artery bypass surgery

provided the original work is properly cited. CC We report a case of bilateral vocal cord paralysis (VCP) that occurred after coronary artery bypass surgery and we review the mechanisms of VCP and the preventable factors. We emphasize to consider VCP if respiratory insufficiency occurs following extubation in cardiac surgery, and an early diagnosis is sure to prevent life-threatening problems such as airway compromise and aspiration pneumonia. A 66-year-old female patient (153.4 cm, 46.8 kg) was scheduled for a coronary artery bypass surgery. She had a medical history of hypertension, coronary artery disease, and diabetes mellitus. Recent coronary angiography showed progressed lesions at the left anterior descending and left circumflex arteries. After the patient was transferred to the operating room and an arterial cannulation was done, anesthesia was induced. Tracheal intubation was performed with a 7.0 mm-internal diameter endotracheal tube (SoftVent Pro, HVLP-Cuff, Murphy, Unomedical, Malaysia) using a direct curved laryngoscope. The balloon was inflated until the cuff pressure was measured as 25 cmH2O by a handheld aneroid manometer (VBM, Germany). The cuff was palpated at the suprasternal notch and the endotracheal tube was fixed at 20 cm from the incisors. An ultrasound guided insertion of a central venous cannula was performed in the right internal jugular vein and a transesophageal echocardiographic (TEE) probe (diameter: 10.5 mm, width of tip: 14.5 mm; TEV5Ms, Siemens Medical Solutions, Mountain View, USA) was inserted without difficulty. After median sternotomy, the left internal mammary artery was harvested and off-pump coronary artery bypass surgery was performed. The cuff pressure of the endotracheal tube was intermittently measured maintaining the intracuff pressure at 25 cmH2O during the operation and the post operation period, and the fraction of inspired oxygen was maintained below 0.5 using medical air and oxygen. A planned extubation was performed after ventilator care for 2 days. Immediately after extubation, the patient complained of respiratory difficulties and an inspiratory stridor was detected. Dexamethasone 5 mg was given and respiration was assisted with a bag-valve-mask for several minutes. The respiratory difficulties were relieved and the stridor disappeared. Chest Xray findings and arterial blood gas analysis were within normal range. Methylprednisolone 25 mg/day was administered due to the suspicion of laryngeal edema and spontaneous breathing was maintained without events under oxygen 10 L/min via a facial mask. One day after extubation the patient complained of hoarseness. The otorhinolaryngeal department was consulted for a vocal cord examination and a gap was shown between the vocal cords and both vocal folds were shown to be immobile. Feeding through a nasogastric tube was started and the patient was kept under close observation. The patient had no respiratory difficulties even though a minimal stridor was detected intermittently. On the 18th post-operative day, the videofluoroscopic swallowing study showed an aspiration at the pharyngeal stage and the patient was put on rehabilitation for dysphagia. On the 20th post-operative day, the fiberoptic endoscopic evaluation of swallowing (FESS) showed improved movement of both vocal cords and no aspiration signs. The patient was discharged one week later and after three months, her voice was normalized and