INTRODUCTION

Tonsillectomy is the second most frequently performed surgical procedure in childhood. Among the complications reported, bleeding stands out as the lead cause of one third of all deaths reported. They are categorized into primary (< 24 hours) and secondary bleeding (> 24 hours) occurring in 5.8 % and 7.5 %, respectively (¹). Vascular bleeding due to pseudoaneurysms or vascular abnormalities of the carotid axis have also been reported. This is the first reported case ever reported of a 7-year-old patient who underwent post-tonsillectomy repair of the carotid axis using an autologous graft from the common carotid artery (CCA) into the left internal carotid artery (ICA) due to recurrent surgical site bleeding refractory to hemostasis and embolization with coils of the left external carotid artery (ECA).

CASE REPORT

This is the case of a 7-year-old patient with a past medical history of tonsillectomy and adenoidectomy. On the third postoperative day, he experienced bleeding and required surgical site reassessment and hemostasis in the operating room. On the fourth post-tonsillectomy day, he complained of pain and a sensation of a left cervical mass associated with ipsilateral eyelid ptosis. The axial emergency coronary computed tomography angiography (CCTA) performed revealed the presence of a left pericarotid hematoma without evidence of active bleeding or dissection. The patient was eventually referred to our center for multidisciplinary evaluation.

Upon arrival, bleeding from the endotracheal tube followed by a cardiac arrest were reported. The latter required advanced resuscitation maneuvers for 10 min. After hemodynamic stabilization, he underwent surgery through a multidisciplinary approach involving the otorhinolaryngology (ENT), vascular surgery, and neuroradiology units.

Using a 6-Fr introducer sheath inserted via left femoral artery, selective arteriography of the left common carotid artery (CCA) was performed. It revealed an irregularity in the contour of the proximal segment of the left external carotid artery (ECA) on an image of around 3 mm suggestive of a small pseudoaneurysm. Areas of stenosis in the facial artery and occlusion of the origin of the lingual artery, which filled late with collateral vessels from the inferior thyroid artery, were also seen.

Embolization was performed using platinum coils, starting from the origin of the left ECA immediately distal to the origin of the superior thyroid artery and towards the segment distal to the origin of the facial artery excluding the region affected.

The oropharyngeal packing was removed, and no active bleeding was ever seen during the examination or at the follow-up angiography. The patient was then transferred to the pediatric intensive care unit (PICU) for further medical management including antiplatelet therapy.

On the 15^th post-tonsillectomy day, the patient experienced another episode of massive oropharyngeal bleeding that required transfer to the operating room for hemostasis of the surgical site. The Vascular Surgery team performed an intraoperative ultrasound that revealed the occlusion of the left external carotid artery (ECA) without further complications at this level, so it was decided not to perform an exploratory neck dissection.

A postoperative follow-up CCTA was performed, and no clear active bleeding site (hematoma in the surgical site) was seen. However, considering the progression and severity of the case, the recurrent and refractory bleeding despite coil embolization and hemostasis of the surgical site, a joint decision was made by the ENT and the vascular surgery teams to proceed with an emergency exploratory left neck dissection.

A longitudinal left cervicotomy was performed, with control of both the CCA and ICA. Exposure of the embolization material (coils) at the proximal and distal ends of the ECA was observed along with avulsion of the carotid bifurcation (Fig. 1).

Figure 1. A. Left carotid bifurcation. Black arrow: Exposed embolization material (coils). 

Due to the extensive carotid bifurcation injury, direct repair was not feasible. The internal saphenous vein (ISV) was explored at right thigh level with proper diameter after dilation and patency. After systemic heparinization, an autologous graft was performed using inverted ISV, from the CCA to the left ICA, with end-to-end anastomosis and ligation of the left ECA. No carotid shunt was used during the procedure, cerebral oximetry was monitored using INVOS, and mean arterial pressures were maintained > 65 mmHg during clamping without need for vasoactive drugs. A digastric muscle flap was necessary to isolate the surgical site from the oropharyngeal cavity (Fig. 2).

Figure 2. A. Left internal carotid artery. B. Left common carotid artery. Black arrow: autologous graft with internal saphenous vein. 

During the postoperative period, the patient was evaluated by the neurology unit due to left facial paralysis, vocal cord paralysis, left Horner's syndrome, and upper and lower motor neuron involvement. No relevant findings were found on the cranial and spinal magnetic resonance imaging (MRI), which was suggestive that these neurological findings were likely due to bleeding and procedures performed at neck level. Motor and speech rehabilitation was initiated, and the patient showed proper progress. After 41 days of hospitalization, the patient was discharged.

After 4 and 12 months of follow-up, the patient had not experienced any new episodes of bleeding and remained completely asymptomatic from a neurological standpoint, both peripherally and centrally.

The carotid bypass remains patent without areas of stenosis as seen on the Doppler ultrasound study.

DISCUSSION

Post-tonsillectomy hemorrhage is a common complication (4.2 %). However, it is rare for this hemorrhage to be due to carotid artery injury (¹). In their systematic review, Leong SCL et al. describe primary and secondary hemorrhage rates of 5.8 % and 7.9 % respectively, with need for surgical evaluation in 0.5 % of cases. Post-tonsillectomy mortality rates vary from one series to the next from 1 in 1000 to 1 in 170 000 while 30 % of these cases are due to injury to the ICA or ECA and their branches (²).

In the pediatric population, the distance between the ICA and the tonsillar fossa can go from 6 mm to 28 mm depending on age and weight. The ECA is more lateral and anterior to the ICA, making it more susceptible to vascular injury after the tonsillectomy.

Similarly, the lower pole of the tonsil is the area with the highest risk of bleeding due to its proximity to the facial artery and lingual artery being the latter being the vessel most commonly involved (³).

One of the most widely described vascular complications after tonsillectomy is the development of pseudoaneurysms in the ICA, ECA or their branches. Head and neck pseudoaneurysms have been reported as early as 4 hours postoperatively and as late as 8 months postoperatively (³). Possible causes for these pseudoaneurysms include trauma, iatrogenic factors, infectious or inflammatory processes, congenital syndromes, radiation therapy or atherosclerosis in the adult population (⁴).

In the medical literature available, cases of pseudoaneurysms treated with coil embolization due to damaged ICA, ECA or aberrant branches of the ECA have been reported (⁴). Also, cases of post-tonsillectomy hemorrhage treated with ligation of the ECA and/or ICA have been reported as well (⁵). Pucher B et al. describe the case of an 11-year-old girl who needed ligation of the left ECA and subsequent embolization of the facial artery and ascending cervical artery due to recurrent massive bleeding (⁶). Sharma et al. present a case of pseudoaneurysm of the ICA in a 36-year-old patient on the first day post-tonsillectomy with occlusion of the ICA at its origin after balloon occlusion testing (⁷). In addition to ligation or coil embolization, the treatment of pseudoaneurysms with N-butyl cyanoacrylate (NBCA) and lipiodol has been described in a 30-month-and-5-day-old patient (²). Regarding the rate of reintervention after tonsillectomy, Nakata Y et al. say that ligation of the ECA was deemed necessary in 1.06 % of patients with delayed bleeding (⁸).

Perforation of embolization material, either in the short or long term, is a rare complication that has been observed in different locations of the body. The most important and frequently described risk factor is radiation therapy. Most cases published of coil perforation occur in the head and neck region. However, cases of coil perforation in the absence of prior radiation therapy have also been reported. At neck level, cases of perforation of coils implanted in the carotid artery have been described with exposure at naso-oropharynx, paranasal sinus, nasal cavity, auditory canal, and cutaneous level (⁹).

Post-tonsillectomy vascular complications have historically been managed with ligation or embolization of the damaged vascular structure. If a carotid artery structure ruptures during neck surgical examination, proximal and distal ligation of the damaged artery, debridement of the wound, closure of salivary fistula, and vascularized flap coverage to protect the exposed arterial structure are advised (¹⁰). In our case, instead of solely performing carotid ligation, we thought that, despite the high technical requirements, revascularization using autologous bypass grafting was a feasible option with potential long-term benefits for a pediatric patient. Therefore, we decided to proceed with the bypass procedure. No other cases of perforation of embolization material with need for carotid repair using prosthetic or autologous bypass grafts have ever been reported in the medical literature to this day.

CONCLUSIONS

Tonsillectomy is a common procedure in both pediatric and adult populations. Post-tonsillectomy bleeding is a common complication that can be life-threatening. Selective arteriography with embolization or ligation of the damaged artery are valid therapeutic options that have been used across history. However, in patients with recurrent and refractory post-tonsillectomy bleeding that remains unresponsive to non-invasive interventions, exploratory surgical intervention can be a valid option, as in our case, to identify and repair the carotid damaged axis during tonsillectomy or due to perforation of the coil embolization material. Therefore, we presented an autologous graft using the ISV associated with a vascularized flap, for the first time, as a technique to repairi and revascularize an injured carotid axis following tonsillectomy in the pediatric age group. Close follow-up is deemed important to assess the behavior of the autologous graft among the pediatric population.