© 2018 Kurt Pfeifer.

Pulmonary Hypertension (PH)

Data Gathering

ASSESSMENT

History

Symptoms

  • Previous PH evaluation (VQ scans, PE CTs, connective tissue disease serologies, sleep studies, PFTs)

  • Previous right heart catheterizations (including response to NO)

  • Previous cardiovascular disease

  • Previous cardiac testing (stress tests, cardiac catheterization, echocardiography, CT coronary angiography)

  • Orthopnea/nocturnal dyspnea

  • Chest pain

  • Exertional dyspnea or lightheadedness

  • Palpitations

  • Diaphoresis

  • Fatigue

  • Syncope

Exam

  • Elevated JVP

  • Edema

  • RV heave

  • Hypoxia

  • Cyanosis

Risk Stratification

Suspected PH

  • If undiagnosed PH suspected, pursue work-up as surgical timeframe allows (McLauglin et al):

    • Cardiopulmonary symptoms that are unexplained

    • Conditions associated with PH:

    • OSA

    • Severe COPD

    • Chronic hemolytic conditions (HbSS)

    • Scleroderma

    • Family history of PH

  • Diagnosed formally by right heart cath (mean pulmonary artery pressure [mPAP] ≥25 mmHg) but initial eval with echo can identify elevated right ventricular systolic pressure, which is equivalent to pulmonary artery systolic pressure (PASP) as long as no RV outflow obstruction (may overestimate PASP with severe tricuspid regurgitation [TR])

  • Probability of PH based on echo findings and determines next steps (Galiè et al):

PH echo diagnosis.jpg
  • Perform further evaluation for those with intermediate or high probability of PH if surgical timeframe allows (Galiè et al, Minai et al)

    • If echo findings suggest clearly related to left heart disease and not severe (PASP <70 mmHg), may be able to empirically treat for left heart disease & forego further evaluation (Minai et al)

      • Moderate-severe left atrial enlargement

      • Moderate-severe diastolic dysfunction

      • Moderate-severe mitral or aortic valve disease

Known PH

  • No well-validated risk stratification tools​ specific for pulmonary hypertension

  • Risk particularly high for patients with group 1 (idiopathic pulmonary arterial hypertension) or in the presence of the following (Minai et al, Pilkington et al, ACC/AHA guideline): 

PH surg risk factors.jpg

Diagnostic Studies

  • BMP  and hemoglobin within 4 months

  • BNP/NT-proBNP if chronically following by PH specialist

  • ECG - within 6 months for non-low risk surgery

  • ECHOCARDIOGRAM if none within 6-12 months

MANAGEMENT

Indications for Surgical Delay

Medication Management

Vasodilator & Diuretic Therapy

Vasodilator & Diuretic Therapy

  • Continue uninterrupted but discuss with PH specialist and anesthesiology

Anticoagulation

  • Indicated for group 4 (chronic thromboembolic pulmonary PH) and potentially indicated for patients with group 1 (idiopathic pulmonary arterial hypertension) 

  • BRIDGING NOT ADVISED unless meets other criteria (for AFib, mechanical valve, or VTE)

Intraoperative Management (Pilkington et al)

  • Perform surgery at center with PH expertise (ACC/AHA guideline)

  • Use warming blankets & IVF warmers (hypothermia induces pulmonary vasoconstriction)

  • Assure deep anesthesia before laryngoscopy & tracheal intubation – blunts sympathetic stimulation & ↑ RV afterload

  • Avoid hypercarbia, acidosis, high inspiratory pressures & high PEEP levels

  • Consider arterial line for frequent ABG

  • Consider TEE or PA catheter in all patients with PH that is severe or accompanied by RV dysfunction

Anesthetic Management (Pilkington et al)

Anesthetic Management (Pilkington et al)

  • Etomidate considered induction agent of choice

  • Neuraxial blockade can be used, but thoracic neuraxial blockade has potential for interfering with RV autoregulation

PH anesthesia.jpg

Hemodynamic Management (Pilkington et al)

  • Perioperative Hemodynamic Goals

    • SBP ≥90 mmHg and/or 40 mmHg above sPAP

    • MAP ≥65 and/or 20 mmHg above mPAP

    • mPAP <35 mmHg or 25 mmHg lower than MAP

    • PVR/SVR ratio <0.5 or stable pre-operative PVR/SVR ratio

    • RAP - lowest possible that maintains MAP > 65 mmHg

    • Cardiac index ≥2.2 L/min/m2

  • Norepinephrine & vasopressin improve RV function through ↑ in RCA perfusion & ↓ in PVR

  • Inotropes (dobutamine) improve RV function & reduce mortality in PH

  • Inodilators (milrinone) beneficial in reducing PVR

Postoperative Management (Minai et al, Pilkington et al, ACC/AHA guideline)

  • Admit to ICU for the immediate post-operative period

    • At high risk for sudden death

    • Requires careful monitoring of fluid balance, oxygenation, BP and HR

  • Optimize fluid balance

  • Ensure adequate pain control

  • Avoid systemic vasodilators

  • Correct hypoxemia and acidosis

  • Use lung-protective mechanical ventilation but use PEEP judiciously

COUNSELING & COMMUNICATION

  • Although recent data show decreases in PH-associated perioperative complications, morbidity remains 6-42% and mortality 4-26% (ACC/AHA guideline)

    • •PH patients poorly tolerate sudden alterations in pulmonary pressures and RV preload & afterload induced by surgery and anesthesia​

  • Avoid surgery unless benefits clearly exceed risks​ (Klinger et al)

  • Carefully coordinate surgery with anesthesiology and PH specialists & perform surgery at center with PH expertise (Klinger et al​)