Postcoarctation repair

It is well known that post-coarctation repair individuals frequently develop a severe hypertensive response. This may be accompanied by abdominal ischemia

as well as disruption of various suture lines. Therefore, frequent examinations of the abdomen as well as the institution of Nitroprusside and/or Esmolol to control the paradoxical hypertension should be initiated. The hypertension associated with this disease state may be prolonged and these patients may need to be switched to oral medications such as Enalapril. Post-aortic aneurysm repair

This is a condition provoked by long-standing essential hypertension. Therefore, in the postoperative period, these individuals usually have sustained systolic hypertension. Again, it is mandatory to control these individual's pressure with drugs such as Nitroprusside or Esmolol.

Risks of allowing the blood pressure to get out of control with a new aortic prosthesis in place are massive postoperative hemorrhage, and occasional disruption of the entire suture line and death.

Dysrhythmias Sinus tachycardia

The therapy of this condition revolves around treating the underlying cause. Under special circumstances where the rapid heart rate may interfere with cardiac output, Esmolol given IV or Metoprolol PO may be utilized to control the tachycardia response.

Atrial premature contractions

This dysrhythmia requires no treatment; however, if the premature contractions are very frequent, they may be early indications of an atrium in which atrial flutter or fibrillation will occur. Under these circumstances, antiarrhythmic drugs such as Digoxin may be started. In addition, the prophylactic use of Metoprolol may prevent these arrhythmias (see section on special medications for explanation). Atrial flutter/fibrillation

No treatment is required if the ventricular rate is reasonable. However, if the rate is fast, one should first attempt to control the rapid ventricular rate with IV Digoxin. Usually, push IV Digoxin to a point where the rhythm comes under control. For more rapid control of the arrhythmia, IV Verapamil can in approximately 20-25% of the cases control the arrhythmia. In addition, IV Diltiazem has been used to slow the rapid rate of contraction. In cases where an immediate response is absolutely necessary, i.e. significant problems in low output state, D.C. synchronized countershock may be utilized. Finally, rapid atrial pacing requiring a special external pacemaker box (a box with the capability of firing greater than 600 times per minute) can occasionally produce control of this rhythm disturbance.

Paroxysmal atrial tachycardia

PAT is a frequent disturbing dysrhythmia. We use prophylactic PO Metoprolol in an attempt to control this problem. However, patients that develop this rhythm disturbance can have a rapid deterioration in cardiac output. The drug of choice for control of this rhythm disturbance is Verapamil. An IV push of between 0.075 and 0.15 mg/kg usually will bring this rhythm disturbance under control. Other medications which can be used to control PAT are IV Digoxin or Metoprolol.

Cardioversion can also be used to control the rhythm disturbance, however, since the advent of Verapamil this is seldom necessary. Sinus bradycardia

This condition can easily be treated with either atrial or ventricular pacing. All postop cardiac patients having pacing wires and hence, connection of the wires to an external pacing box can result in immediate control of the rhythm problem. In those individuals where the wires are not present or where they are not functional, IV push of atropine or continuous infusion of isoproterenol may relieve the rhythm disturbance. Nodal rhythm

No treatment is required if the rate is reasonable and blood pressure is satisfactory. However, if the rate drops and cardiac output is diminished, pacing, either atrial or ventricular, becomes the treatment of choice. Occasionally, where both atrial and ventricular wires are in place, AV sequential pacemaking may be utilized so as to gain the added improvement in cardiac output by allowing the atrial kick. In situations where pacing is not available, IV infusion of isoproterenol may be utilized.

Premature ventricular contractions

A few premature ventricular contractions need only be watched, however, frequent premature contractions (greater than 5/min), those occurring in runs, or those with an R on T phenomenon require therapeutic intervention. The primary means of treatment are the institution of lidocaine. Lidocaine is usually given as a 1 mg/kg dose followed by a continuous drip between 2-4 mg/min. When these arrhythmias occur one should check for the presence of hypoxemia, for an inappropriate potassium serum level, and for acid base imbalance. Problems with any of these should be corrected immediately. Ventricular premature contractions may also be controlled by ventricular overdrive pacing. For more long term control of persistent ventricular premature contractions, the institution of oral procainamide, quinidine or other drugs may be useful.

Ventricular tachycardia

Ventricular tachycardia is a medical emergency. The immediate institution of Lidocaine followed by countershock if the arrhythmia continues should occur. These patients will require careful and continual cardiac rhythm monitoring.

Ventricular fibrillation

This disturbance requires immediate medical intervention. The treatment requires rapid asynchronous defibrillation. For patients who have had prolonged periods of ischemia associated with this rhythm disturbance, IV bicarbonate, epi-nephrine and defibrillation may be all required.

Pulmonary Care

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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