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Definition

Accidental arterial penetration during venipuncture or catheterization will result in a significant hematoma formation but no other consequences if quickly recognized. Administration of medications into the arterial circulation is associated with severe and violent reactions when it involves the cerebral circulation or may be associated with arteriospasm and tissue necrosis if it involves a peripheral artery.

Risk factors

 Anatomical location: The common carotid

 Poor lighting

 Fractious or insufficiently restrained patient

 Inability or inexperience to recognize anatomic landmarks, and accessing the vein in the lower part of the neck [2]

 Use of smaller gauge needles

Pathogenesis

The needle is advanced and placed into the arterial lumen inadvertently and the solution injected. The common carotid artery is the most common artery to be accidentally punctured, especially in the caudal two‐thirds of the neck, because of the close proximity of the carotid artery to the jugular vein and common use of the jugular vein for venous access [1, 2]. Risk of inadvertent arterial injection or catheterization is less with the cephalic vein, lateral thoracic vein, and saphenous veins, because there are no adjacent arteries. Smaller gauge needles prevent recognition of inadvertent arteriopuncture.

Prevention

Adequate knowledge of anatomy is required; inject into the cranial aspect of the jugular vein whenever possible. Adequately restrain the patient and perform injection in areas with adequate lighting. Use needles not smaller than 18–20 gauge, although these calibers also show weak or absent pulsations [9].

Diagnosis

Accidental penetration of the artery is typically associated with pulsatile and projectile ejection of bright red blood from the catheter or needle; however, projectile arterial blood is not always apparent [9, 10]. Smaller gauge (18–20 gage and smaller) needles are associated with weak or absent pulsations [9]. Placement of the bevel against the arterial wall or incomplete seating of the needle in the vessel may also prevent forceful ejection of blood. The most serious consequence of arterial catheterization is injection of medications into the arterial system. Intracarotid injections are the most severe and serious of these accidental injections because of the typically immediate and violent reactions by the patient. Clinical signs can range from disorientation to hyperexcitability to seizures and death.

Treatment

If arterial puncture is recognized, the needle or catheter should be removed and firm direct pressure applied to the site immediately. Reactions to accidental intracarotid injections can be immediate and violent. Personnel and patient safety should be prioritized. Immediate treatment of accidental intracarotid injection includes sedation and/or anticonvulsive medications (alpha‐2 agonists, benzodiazepines, and phenobarbital) and provision of neuroprotective treatments (dimethylsulfoxide, corticosteroids, and mannitol) [10].

Expected outcome

The severity of intracarotid injections depends on the amount and type of medication administered. Oil‐based formulations, such as phenylbutazone, are associated with fatal reactions [10]. Outcome may also be affected by injuries incurred subsequent to the injection (e.g. head trauma, etc.). Although systemic reactions are not pronounced with accidental injection of other arteries, ischemia and necrosis of the tissues supplied by the artery may occur if the artery thromboses.