Systemic and Pulmonary Hypertension

The flashcards below were created by user doza04 on FreezingBlue Flashcards.

  1. Systemic HTN
    • BP: 140/90
    • Essential: 95% (presumed to have ischemia)
    • Secondary: 5%
    • Path: Final pathway is salt and water retention. 
    • Risk: ischemic heart disease and a major cause of congestive heart failure, cerebral vascular accident (stroke), arterial aneurysm, and ESRD.
  2. Causes of Essential Hypertension
    • Increased sympathetic response (stress)
    • High Na Intake
    • Inadequate K and Ca intake
    • Increased Renin (RAA pathway)
    • Vasodilator deficiencies (NO&prastaglandins)
    • Diabetes Mellitus
    • Obesity
    • Alcohol and tobacco use
  3. Treatment of Essential Hypertensionn (Pharmacological)
    • 1. Thiazide diuretics: often initial
    • 2. ACE inhibitors: useful for pts w/ heart failure. 
    • 3. If monotherapy is unsuccessful, a drug from a different class is used.
    • 4. Consider ARBs, Aldosterone antagonist, diuretics (thiazide, loop, K sparing), B-Blockers, vasodilators, or Ca Channel Blockers,
  4. Antihypertensives in Perioperative
    • 1. Continue antihypertensives to decrease risk of rebound HTN (B-blockers, clonidine)
    • 2. Discontinue ACE inhibitors, as they do not cause rebound HTN.
  5. Treatment for a Hypertensive Emergency
    • Sodium Nitroprusside 0.5-10mcg/kg/min
    • Nicardipine
    • Dopamine 
    • Esmolol
    • Labetalol
  6. Hypertensive Emergency
    • Patients with evidence of acute or ongoing target organ damage. 
    • Parturient patients w/ diastolic >100
    • Normal patients >150
    • Goal: decrease diastolic pressure promptly & gradually. Rapid decrease may provoke coronary/cerebral ischemia. 20% decrease in the first hour.
  7. Treatment of Primary Aldosteronism
    • Spironolactone: for women. May cause gynecomastia in men. 
    • Amiloride: for men
  8. ACE Inhibitors
    • Risk of preoperative hemodynamic instability and hypotension.
    • Fluid maintenance is critical. 
    • Discontinue ACEi 24-48 hours prior to surgery
    • Anesthetics: depress autonomic response
    • ACEi: blunt the renin-angiotensin-aldosterone system
    • Vasopressin system: only available system to regulate BP following loss of RAA and autonomic systems. Likely to be volume dependent. 
    • May cause hyperkalemia.
  9. Angiostensin Receptor Blockers (ARBs)
    • Prevent Angiotensin II from binding to its receptor. 
    • Blockade of the renin-angiotensin-aldosterone system increased potential for hypotension during surgery. 
    • Discontinue ARBs 24 hours prior to surgery
  10. Preoperative Evaluation of a Hypertensive Patient
    • No evidence of increased postoperative complications when a hypertensive patient undergoes elective sx. 
    • Try to make patient normotensive prior to surgery, 
    • Co-existing HTN may increase postop incidence of MI w/ previous history and near complications iduring endarterectomy. 
    • If there is end organ damage, an elective procedure may need to be postponed to improve end-organ damage.
  11. Induction of Anesthesia
    • Rapid IV induction may produce an exaggerated decrease in BP
    • IV induction drugs do not predictably suppress circulatory response of tracheal intubation
    • High risk ischemia patients may benefit from maneuvers that blunt the autonomic response to intubation: deep inhalation anesthetics opioid, lidocaine, B-blocker, or vasodilator. 
    • Minimize DL time.
  12. Intraoperative HTN
    • Often due to increased surgical stimulation (light anesthesia)
    • BP control w/ any volatile anesthetic (decreasd SVR and contractility), opioids+N2O
    • Any muscle relaxant can be used.
  13. Intraoperative Hypotension
    • Tx by decreasing depth of anesthesia and increasing fluid infusion. 
    • Pt taking ACEi or ARBs is still responsive to IV fluids, sympathomimetics, and vasopressin
  14. Pulmonary Arterial Hypertension
    • Pulmonary HTN: MAP > 25mm Hg
    • Average: MAP 12-16 mm Hg (18-25/6-10 mm Hg)
    • At risk for RV Failure, hypoxemia, and coronary ischemia.
    • S/S: breathlessness, fatigue, murmurs of pulmonic insufficiency or tricuspid regurgitation, S3 gallops, peripheral edema, hepatomegaly, ascites
    • Physio: Increased RV after load, decreased RV stroke volume, low systemic output, and hypotension
    • Hypoxemia Risk: 1.Increased Right-sided pressure increases R-L shunting through a patent foramen ovale, 2.During fixed CO, the increased oxygen extraction with exertion will produce hypoxemia, 3.V/Q mismatch can result in perfusion of poorly ventilated alveoli.
  15. Treating Pulmonary Hypertension
    • Oxygen, Anticoagulation, and Diuretic Therapy: O2 reduces hypoxic pulmonary vasoconstriction, diuretics decrease preload, and anticoagulation decreases risk of thrombus and thromboembolism. 
    • Ca Channel Blockers: For those responsive to  vasodilator trial (Nifedipine, nicardipine, and amilodipine)
    • Phosphodiesterase inhibitor: Produce pulmonary vasodilation and improve CO
    • Inhaled Nitric Oxide: Smooth muscle relaxation and vasodilation in well-ventilated alveoli which improves V/Q mismatch. 
    • Prostacyclins: Systemic and pulmonary vasodilators (also antiplatelet). May lead to bronchospasm, rebound HTN, 
    • Endothelin Receptor Antagonists: Lower PA pressure ad PVR and improve RV function, exercise tolerance
  16. Anesthetic Management of Pulmonary Hypertension
    • Increased risk of right heart failure: increased RV after load, hypoxemia, hypotension, and inadequate RV preload. 
    • Sedatives with caution since respiratory acidosis may increase PVR. 
    • Medications for PAH should be continued throughout the perioperative period: infusions of pulmonary vasodilators, diuretics to control edema. 
    • Reduced SVR by volatiles or sedatives may be dangerous due to fixed CO.
    • Ketamine and etomidate may suppress vasorelaxation and should be avoided. 
    • Hypoxia, hypercarbia, and acidosis must be controlled since they increase PVR.
    • Inhalationals, neuromuscular blockers, and opioids (except histamine release) can be used safely
    • Pulmonary vasodilators: milrinone, NTG, or prostacyclin should be available.
  17. Induction for Patient with Pulmonary Hypertension
    • Sidafenil or L-arginine may be useful for newly diagnosed. 
    • Opioids (except histamine), propofol, thiopental, and depolarizing/non-depolarizing neuromuscular blockers may be used.
    • Avoid: ketamine and etomidate since they may suppress pulmonary vasorelaxation. 
    • Hypotension: Treated with NE, phenylephrine, or fluids. 
    • Severe pulmonary HTN: Tx with pulmonary vasodilator such as milrinone, NTG, NO, or prostacyclin.
  18. Meds that may cause HTN
    • MAOIs
    • TCAs
    • SNRIs
    • COMT Inhibitors
    • Amphetamines: Adderall,
  19. Hypertensive Emergency (Encephalopathy)
    • Primary: Nitroprusside, labetolol, fenolodopam, nicardipine
    • Caution: Cerebral ischemia may occur due to drop in BP
  20. Hypertensive Emergency (Myocardial ischemia)
    • Primary: NTG
    • Caution: Avoid B-blockers in acute CHF
    • Notes: Include morphine and oxygen (MONA- morphine, oxygen, NTG, aspirin)
  21. Hypertensive Emergency (Acute pulmonary Edema)
    • Primary: NTG, nitroprusside, fenoldopam
    • Caution: Avoid B-blockers in acute CHF
    • Notes: Include morphine, diuretic, and oxygen
  22. Hypertensive Emergency (Aortic Dissection)
    • Primary: Esmolol, vasodilators, trimethaphan
    • Caution: vasodilators cause reflex tachycardia
    • Goal: Lessen pulsatile force of LV contraction.
  23. Hypertensive Emergency (Renal Insufficiency)
    • Primary: Fenoldopam, nicardipine
    • Caution: Tachyphlaxis with fenoldopam
    • Notes: Avoid ACEis and ARBs. May require hemodialysis
  24. Hypertensive Emergency (Preeclampsia/eclampsia)
    • Primary: Methyldopa, hydralazine, Mg-sulfate, labetalol, nicardipine
    • Caution: Lupus-like syndrome w/ hydralazine, risk for flash pulmonary edema, Ca channel blocker may reduce uterine flow.
    • Notes: Definitive is delivery. ACEIs and ARBs are contraindicated due to teratogenic effect
  25. Hypertensive Emergency (Pheochromocytoma)
    • Primary: Phentolamine, phenoxybenzamine, propanolol
    • Caution: Unopposed alpha stimulation following B-block worsens HTN
  26. Hypertensive Emergency (Cocaine intoxication)
    • Primary: NTG, nitroprusside, phentolamine
    • Caution:Unopposed alpha stimulation following B-block worsens HTN
Card Set:
Systemic and Pulmonary Hypertension
2015-09-18 01:22:20
Hypertension Anesthesia

Systemic and Pulmonary Hypertension Anesthesia
Show Answers: