Accidental Intra-arterial Injection of Adenosine in a Child with Supraventricular Tachycardia

Many case reports and incidences of accidental intra-arterial (IA) injection of medications have been published so far[1,2]. The common medications reported are barbiturates and benzodiazepines, including the anesthetic agents. There is only one case report of accidental intra-arterial injection of adenosine[3] . A 14 years old boy was referred from a peripheral hospital as a case of supraventricular tachycardia (SVT). He was complaining of palpitation and chest pain. His heart rate was 200/min and was hemodynamically stable (temperature 36.7oC, breath rate 25/min, blood pressure 110/70 mmhg, capillary refill time of 2 seconds, pulse oximeter oxygen saturation of 97% without oxygen administration and a normal sensorium). The body weight was 50 Kg. The systemic examination revealed S3 gallop and tender hepatomegaly. The ECG confirmed SVT. The vagal maneuver (carotid massage) failed. Intravenous adenosine was ordered. 22-gauge intravenous cannula was inserted into a superficial vessel over the radial styloid process at the base of the anatomical snuff box of the right wrist. The intravenous cannula was fixed after flushing with 1 ml of water for injection without pain or difficulty. The adenosine injection 5 mg was administered as a fast bolus followed immediately by rapid push of 10 ml isotonic saline with the help of a 3-way stop-cock. This immediately resulted in intense pain and flushing and hyperemia of the skin of the right hand. He complained of blurring of vision and dizziness. These symptoms completely disappeared spontaneously within 5 minutes. The cannula was not removed immediately. It was noticed that the black flow of blood was bright red in color. There was pulsatile movement of blood in the intravenous tubing with back flow of blood in the tubing when the saline bottle was attached to the cannula. Blood gas analysis from the cannula revealed pHa 7.44, PaCO2 of 34 mmHg, and a PaO2 of 100 mmHg while the patient was not administered oxygen, confirming an inadvertent arterial cannulation. The cannula was removed and newly placed in the left cubital vein and a repeat dose of adenosine was administered uneventfully. The SVT converted to normal rhythm. The subsequent examination of the right hand revealed no abnormality.