Chapter 37. Intracardiac Injection

The practice of intracardiac injection originated in the 1800s. It was quite commonly performed throughout the 1960s, as it was thought to be the most expeditious route of drug delivery during a cardiac arrest.1,2 By the mid-1970s, the practice of intracardiac injection declined. Safer and simpler routes of medication administration (i.e., intravenous, endotracheal, and intraosseous) became available. Experimental data suggested that there was no advantage to intracardiac injection over intravenous administration of medications. Cardiopulmonary resuscitation (CPR) must be interrupted to perform an intracardiac injection. In difficult patients or in inexperienced hands, the time required for this procedure may be too prolonged. Finally, many serious complications may occur as a result of an intracardiac injection.2

The technique of intracardiac injection is similar to that of a pericardiocentesis (Chapter 36). Both techniques use the same anatomic landmarks, the same anatomic approach, and the transthoracic insertion of a needle through the pericardium. In performing a pericardiocentesis, the tip of the needle is inserted into the pericardial space. Intracardiac injection requires the tip of the needle to be inserted through the myocardium and into a cardiac chamber. Echocardiography or bedside ultrasound may be useful in pericardiocentesis to avoid the lung or myocardium.

Time is of the essence when performing an intracardiac injection. Since the objective is to quickly enter the myocardial cavity, ultrasonographic guidance is generally not necessary. Keeping this in mind, certain situations such as COPD, a prior lung resection, or dextrocardia may benefit from ultrasonographic guidance to avoid puncturing the lung.

The technique of intracardiac injection is easy to teach, is rapid and simple to perform, and requires no special equipment. It begins with identification of the anatomic landmarks required to perform the procedure (Figure 37-1). For the subxiphoid approach, identify and palpate the xiphoid process of the sternum and the left costosternal angle. For the left parasternal approach, identify and palpate the left fourth or fifth intercostal spaces immediately adjacent to the sternum.

The primary indication for an intracardiac injection is when vascular access is not readily available or unobtainable in a patient with asystole, pulseless electrical activity, pulseless ventricular tachycardia, or ventricular fibrillation. The intracardiac injection of resuscitative medications may be warranted and can be attempted as a last effort to resuscitate the patient if other routes of medication administration have failed.

As candidates for this route of medicinal delivery have undergone a cardiac arrest, there are no absolute or relative contraindications to performing this procedure. A few clinical conditions may make the procedure more difficult to perform. Chronic obstructive pulmonary disease can shift the heart from its normal position and increase the risk of a pneumothorax (with or without tension). Therapeutic or overanticoagulation may result in a hemopericardium and cardiac tamponade. Dextrocardia requires identification of different anatomic landmarks and alterations in needle positioning.

• Povidone iodine or chlorhexidine solution
• 18 gauge spinal needle or 18 gauge 3½ in. needle (for adults)
• 22 gauge spinal needle (for children)
• Syringes, 5 and 10 mL
• Nasogastric tube
• Epinephrine, 1:1000 and 1:10,000

Epinephrine is the only resuscitative medication that should be administered by intracardiac injection. Administer 1 mg of epinephrine as the initial and subsequent doses in an adult patient. Administer 0.01 mg/kg (or 0.1 mL/kg) of the 1:10,000 concentration of epinephrine as the initial dose in children. Administer 0.1 to 0.2 mg/kg (or 0.1 to 0.2 mL/kg) of the 1:1000 concentration of epinephrine for subsequent doses in children.

This procedure is often performed on a patient who is clinically “dead” and as a last effort at resuscitation. An informed consent is not required to perform this procedure. The patient will be supine with CPR in progress. If time permits, insert a nasogastric tube to decompress the stomach. Apply povidone iodine or chlorhexidine solution to the area around the lower sternum, xiphoid process of the sternum, upper epigastric, and left costosternal angles. Identify, by palpation, the anatomic landmarks required to perform the procedure. Draw up the required dose of epinephrine into a syringe or use prefilled syringes. Attach a spinal needle to the syringe containing the epinephrine.

The two routes for intracardiac injection are the subxiphoid and left parasternal approaches (Figure 37-1). Both are utilized in a similar fashion. The left parasternal approach offers a more direct and shorter route. However, it is associated with a higher rate of complications. Both approaches require cessation of CPR in order to perform the procedure. The procedure of intracardiac injection should be performed as rapidly as possible to avoid prolonged cessation of CPR, but not at the expense of safety to the Emergency Physician, Nurses, and ancillary staff. It should take less than 10 seconds to perform an intracardiac injection.

Subxiphoid Approach

Stop performing CPR. Stop ventilating the patient and allow the lungs to passively deflate. Identify the spot 1 cm to the left of the patient's xiphoid process in the costosternal angle (Figure 37-1). Insert the needle with the bevel up, at a 30° to 45° angle to the skin of the abdominal wall, and aimed toward the patients left shoulder. Advance the needle while applying negative pressure to the syringe. Stop advancing the needle when blood flows freely into the syringe. This signifies that the tip of the needle is within the cardiac chamber. Quickly inject the epinephrine, then withdraw the needle. Resume CPR and ventilation of the patient.

If the attempt at intracardiac injection is unsuccessful, the needle should be withdrawn and flushed and intracardiac injection reattempted. The needle can become plugged with subcutaneous fat. CPR and ventilation must be resumed after each attempt at intracardiac injection, whether successful or not. Variations on the direction of the needle can be made for subsequent attempts. The needle may be directed toward the suprasternal notch, left midclavicle, or right midclavicle.

As an alternative, the spinal needle can be inserted through the skin and into the subcutaneous tissue with its obturator in place. Remove the obturator when the tip of the spinal needle is in the subcutaneous tissue. Attach the syringe containing epinephrine to the spinal needle. Gently depress the plunger of the syringe to expel the air within the needle into the subcutaneous tissues. Advance the needle while applying negative pressure. Stop advancing the needle when blood flows freely into the syringe. Quickly inject the epinephrine, and withdraw the needle. Resume CPR and ventilation of the patient.

Left Parasternal Approach

This approach utilizes the fourth or fifth intercostal space, approximately 1 cm (or 1 finger breadth) lateral to the left sternal border (Figure 37-1). Stop performing CPR. Stop ventilating the patient and allow the lungs to passively deflate. Insert the needle perpendicular to the chest wall. Stabilize the needle with one hand and the syringe with the other. Advance the needle with both hands and without excessive force.3 It is very easy to plunge into the heart if too much force is applied to the needle. Apply negative pressure to the syringe as it is advanced. Stop advancing the needle when blood flows freely into the syringe. Quickly inject the epinephrine, then withdraw the needle. Resume CPR and ventilation of the patient.

Infants and Children

The technique of intracardiac injection for infants and children is essentially the same as that described above for the adult patient.4 While the subxiphoid approach has been “adopted as the standard,” the left parasternal approach can also be effectively utilized. Use a 22 gauge spinal needle for infants and children. Use caution when inserting and advancing the spinal needle since the pediatric skin and subcutaneous tissue are thin and easily penetrated. The dose of epinephrine administered is weight-based and varies from the initial dose to subsequent doses (see the “Equipment,” section, for discussion).

Overall, according to pooled data, complications are rare.2,5–7 A pneumothorax is the most common complication, especially with the parasternal approach. Other reported complications include coronary artery laceration, myocardial laceration, hemopericardium, cardiac tamponade, pulmonary artery laceration, and perforation of the stomach or liver. Intramyocardial injection has been reported and is associated with intractable ventricular fibrillation. Identification of the appropriate anatomic landmarks for needle insertion and direction can minimize complications. Careful adherence to proper technique can also minimize complications. The use of a small-gauge spinal needle and the subxiphoid approach may result in fewer complications versus a large-gauge needle and the left parasternal approach.8

Although intracardiac injection is an effective route of medication delivery to a patient in cardiac arrest, its popularity has declined due to safer, simpler, and more effective methods of vascular access. When intravenous access is not readily accessible or when the endotracheal administration has not provided the desired effect, intracardiac injection should be considered as an alternative technique. It is important not to permit prolonged cessation of CPR during the procedure.