Discussion

In patients who have previously undergone interventional procedures and cardiac surgeries, the traditional femoral approach is not always possible, and different vascular accesses are required. Carotid, axillary, brachial, and radial arteries can be used when necessary for vascular access. Azzolina et al. proved in the late 1960s that cardiac catheterisation in infants and young children could be performed using the common carotid artery. ^{Reference Azzolina, Eufrate and Allella3} In the neonatal period, the axillary artery is wider than the femoral artery, providing easier access to pathology, and not affecting the extremity circulation compared to the femoral artery. Previously, access was gained with the cut-down technique, but nowadays, ultrasound-guided carotid access is performed. ^{Reference Ligon, Kim, Vincent, Bauser-Heaton, Ooi and Petit4} In this presented case, the procedure was performed in a timely manner under ultrasound guidance since an access could not be obtained from the femoral arteries. In a study evaluating vascular complications in children undergoing catheterisation, Roushdy et al. reported that large sheath size, young age, and low body weight increase the risk of complications. The most common complications reported in this study were temporary loss of pulse (%17.6), bleeding (%3), subcutaneous haematoma (%2), vessel tear (%0.2), and vein thrombosis (%0.2). ^{Reference Roushdy, Abdelmonem and El Fiky5} In a study conducted by Justino et al., 42 children who had undergone an interventional cardiac catheterisation procedure through the common carotid were evaluated; a pseudoaneurysm formation was reported only in a single patient. ^{Reference Justino and Petit1} In our study, we evaluated the ductus stent implantation in newborns with a ductus-dependent pulmonary circulation. Arterial access was gained via the common carotid artery in 14 patients, and no patient developed a pseudoaneurysm. ^{Reference Onalan, Odemis and Saygi6} Pseudoaneurysm develops after damage to the arterial wall, with a permanent connection between the artery and the cavity formed outside the vessel. It differs from true aneurysm by not participating in the formation of the three layers of the arterial wall. ^{Reference Gulla, Chaudhary, Sahoo and Sachdev7}

Pseudoaneurysm is a very rare complication and is mostly caused by not applying enough compression following interventional procedures. ^{Reference Katzenschlager, Ugurluoglu and Ahmadi8} It may result in life-threatening complications due to rapid bleeding and airway compression. After the sheath removal, pressure was applied to the area for 10 minutes and there was no evidence of swelling in the procedural area the next day. The patient’s family stated that they noticed the swelling on the left side of the infant’s neck 10 days later and that there was no previous noticeable difference. In our study protocol, Doppler ultrasound is not routinely planned for every patient following the procedure. Further, patients with no pulse, who develop pain or swelling that are inappropriate with their clinical picture, are evaluated with an ultrasound before their discharge. Routine post-procedure ultrasound may be beneficial in early detection of pseudoaneurysms, especially in newborns and infants. Ultrasonography is a cost-effective, non-invasive, accessible, and effective imaging tool in the diagnosis of pseudoaneurysm. It guides the diagnosis with its high sensitivity and specificity. CT provides a better understanding of the anatomy and the relationship of the pseudoaneurysm with the surrounding structures. The size of the pseudoaneurysm neck and imaging from different axes are guiding the treatment plan. For imaging, conventional angiography is the gold standard. Despite the invasive nature of the procedure, it is preferred more in patients who are only being considered for simultaneous treatment. ^{Reference Sarioglu, Capar and Belet9} After identifying the pseudoaneurysm with ultrasound with Doppler in our patient, the structure, location, and relationship of the aneurysm with other tissues were clearly demonstrated with CT. The first choice of treatment in patients with pseudoaneurysms detected earlier is ultrasound-guided compression and percutaneous thrombin injection. If these procedures fail, interventional procedures including coil embolisation, vascular plugs, and stent deployment options are mostly sought for. ^{Reference Zhong, Islim, Sundararajan, Tahir, Goddard and Patel10} In patients for whom interventional treatment options are not deemed possible, a surgical approach can be an option to successfully eliminate the pseudoaneurysm in a way that ensures vascular continuity. In this case, ultrasound-guided compression was not considered because of the patient’s late presentation, the possibility of embolism, and airway compression associated with the pseudoaneurysm.