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A 12-year-old girl presents with dyspnea on exertion, chest pain, syncope, and a murmur. She is scheduled for a diagnostic cardiac catheterization.
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Physical exam: Thin girl, loud P2, right-sided gallop, pulsatile liver.
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Chest x-ray: Large central pulmonary arteries (PAs), oligemic lung fields.
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Echocardiogram: Tricuspid regurgitation, significant TR jet, right ventricular (RV) hypertrophy, and a septum that bulges into the left ventricle during systole.
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PREOPERATIVE CONSIDERATIONS
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Pulmonary hypertension (PH) is defined as mean pulmonary arterial pressure >25 mm Hg at rest and may be associated with familial, endocrine, cardiac, hepatic, thrombotic, HIV, pulmonary, or rheumatologic disease. The onset of symptoms is often insidious; the dyspnea is often misdiagnosed as asthma, and the syncope is confused with seizures. The incidence is higher in populations living at high altitude, and it occurs more often in females than in males. Physiologically, PH patients with left-to-right shunts have too much blood flow, while PH patients with increased pre- or postcapillary resistance have too little blood flow. Increased precapillary resistance may be associated with vascular obstruction, constriction, or obliteration. Inhaled nitric oxide (iNO) is beneficial only in precapillary constriction. iNO will increase the flow in left-to-right shunts and cause pulmonary edema in patients with postcapillary resistance.
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ANESTHETIC MANAGEMENT
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Benzodiazepine premedication is recommended to blunt catecholamine surge.
Upper respiratory tract infection will increase risk and also make the data unreliable—postpone the case.
Narcotics, benzodiazepines, IV sedatives, and potent agents are acceptable, but avoid hypoventilation and hypotension.
Avoid increases in intrathoracic pressure, eg, through coughing, straining, or Valsalva maneuver.
Even a small degree of hypoxia, hypercarbia, acidosis, catecholamine release, or airway obstruction will raise PA pressure. Monitor O2 saturation and end-tidal CO2 closely.
Once the sheath is placed, you can decrease the amount of anesthetic.
Maintain coronary perfusion. If you cannot lower the RV pressure, raise the mean arterial pressure.
If the patient is on a continuous prostaglandin infusion, do not interrupt it.
Patients with atrial communications will shunt right to left and desaturate but will not arrest during a pulmonary hypertensive crisis.
In case of hypotension, consider administering vasopressin as a systemic vasoconstrictor.
Death during the procedure is often due to RV ischemia or pulmonary hemorrhage. Monitor the electrocardiogram for signs of isc-hemia (especially bradycardia) and the fluoroscopy for signs of hemorrhage.
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POSTOPERATIVE CONSIDERATIONS
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Continue to avoid the Valsalva maneuver.
If the patient develops a pulmonary hemorrhage, sedate, paralyze, and consider one lung ventilation.
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DOs and DON’Ts
⊗ Avoid platelet transfusions. The serotonin increases PA pressure.
⊗ Avoid coughing during the extubation; consider deep extubation if the patient has a good airway.
✓ Oxygen will often lower PA pressure in patients with congestive heart disease or chronic lung disease.
✓ iNO will often lower PA pressure ...