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Introduction

Perioperative management of the chronically anticoagulated patient is a problem commonly faced by surgeons today. One must weigh the risk of thrombotic complications when withholding anticoagulation against the increased risk of intraoperative and postoperative hemorrhage when continuing anticoagulation in the perioperative period. The situation becomes even more challenging when considering tonsillectomy, a procedure with the known complication of postoperative hemorrhage. Hemorrhage after tonsillectomy, while rare, can have potentially devastating complications.

Tonsillectomy is one of the most common ambulatory procedures performed in the US annually . Post-tonsillectomy hemorrhage can be defined as primary, which occurs during the first 24 h, and secondary, which occurs after the first 24 h. Post-tonsillectomy hemorrhage is infrequent with rates varying from 0.2% to 2% but is a potentially fatal complication . As a result, the management of anticoagulation in the perioperative period should be carefully considered for patients undergoing tonsillectomy.

The most common indications for long-term anticoagulation are atrial fibrillation, venous thromboembolism, and the presence of mechanical heart valves. Long-term anticoagulation has traditionally involved the use of warfarin. In patients who undergo a short-term interruption of warfarin therapy, thromboembolism rates are low though they are noted to occur . As a result, a number of strategies have been used to minimize the time off of anticoagulation in the perioperative setting. Traditionally, a heparin bridging strategy has been used. This technique often requires a lengthy inpatient hospitalization with the patient undergoing anticoagulation with unfractionated heparin (UFH) while waiting for the International Normalized Ratio to fall to subtherapeutic levels. More recently, low molecular weight heparins (LMWH) have been used as bridging therapy. LMWH are easier to administer and are cost effective as they do not require inpatient hospitalization for administration . Standardized bridging therapies have been proposed, but there currently is no consensus on the most effective bridging strategy . A single case report was found in the literature describing the case of a single tonsillectomy being performed using LMWH as bridging therapy for a patient on long-term anticoagulation with warfarin .

New oral anticoagulants such as rivaroxaban, dabigatran, and apixaban are emerging as a viable alternative to anticoagulation with warfarin. Rivaroxaban is a direct Factor Xa inhibitor that may be an alternative to warfarin for short and long-term anticoagulation. Rivaroxaban has been shown to be efficacious in the treatment of systemic venous thromboembolism, pulmonary embolism, and atrial fibrillation while potentially improving the risk–benefit profile in anticoagulation for these clinical scenarios . Rivaroxaban is dosed once daily and has a half life of 5–9 h in healthy subjects and 11–13 h in the elderly . To our knowledge, there is no literature to indicate the safety of performing tonsillectomy on patients who are anticoagulated with new oral anticoagulation agents. We present the case of a 38 year old female on rivaroxaban with a history of deep vein thrombosis and pulmonary embolism who successfully underwent tonsillectomy.

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Case report

A 38 year old female with a past medical history including asthma, two episodes of deep vein thrombosis, and one episode of pulmonary embolism who was on chronic anticoagulation with rivaroxaban was referred to the otolaryngology clinic of a tertiary medical center by her primary care physician for recurrent tonsillitis. The patient had experienced four to five episodes of tonsillitis annually for the last four to five years.

Eight years prior, the patient had a miscarriage followed by the development of multiple pulmonary embolisms. Evaluation was negative for deep vein thrombosis initially. She was started on enoxaparin and warfarin. She returned to the emergency department approximately 1 week later and was found to have an internal iliac deep vein thrombosis. Shortly thereafter, she had an inferior vena cava filter placed. Eight years later, she had a second episode of deep vein thrombosis requiring a thrombectomy and venoplasty. At that time, she was started on rivaroxaban. Six months later, she presented to the otolaryngology clinic for evaluation.

The decision was made to proceed with tonsillectomy secondary to recurrent tonsillitis. The patient was instructed to hold rivaroxaban the morning of her scheduled operation. Two months after initial evaluation, she successfully underwent adenotonsillectomy. Electrocautery was used to remove the tonsils, and suction cautery was used to ablate the adenoid pad. The estimated blood loss during the operation was 5 mL. The patient was discharged on the same day of surgery. The patient restarted rivaroxaban on postoperative day one. She presented to the emergency department approximately one week postoperatively secondary to throat pain. She did not require admission and was discharged with analgesic medications. She was followed for a period of one month prior to being discharged from clinic. She had no episodes of postoperative hemorrhage throughout her follow up.