Severe Ronald Pearl, MD, PhD Professor and Chair Department of Anesthesiology Stanford University Rpearl@stanford.edu Nothing to Disclose
65 year old female Elective knee surgery NYHA Class 3 Aortic stenosis 50 mm gradient Two Patients 65 year old female Elective knee surgery NYHA Class 3 Pulm hypertension PAP = 50 mm The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Preoperative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension Clinical Presentation of Idiopathic Pulmonary Arterial Hypertension Echocardiography in PH Dyspnea Chest pain Syncope RVH Not right heart failure (edema, ascites, JVD, hepatomegaly) Lee, J Am Soc Echocardiogr 2007; 20:773
Echocardiography in PH Calculation of spap: P=4V² Mitral stenosis Left ventricular dysfunction Cardiac shunts Estimation of RAP and CO RV function The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Preoperative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension Lee, J Am Soc Echocardiogr 2007; 20:773 Risk of Surgery in Patients with Depends on severity of pulmonary hypertension (PAP) and the adequacy of RV compensation (RAP, CO, SvO 2, RV function, functional status) Compensated RV Failure RV Afterload RV Hypertrophy RV Contractility Normal CO
Compensated RV Failure Decompensated RV Failure PVR PVR RV Afterload RV Afterload RV Output RV Hypertrophy RV Hypertrophy LV Output RV Contractility RV Contractility Blood pressure Normal CO Normal CO RV Coronary perfusion Cycle of RV Failure RV Afterload RV Hypertrophy PVR RV Output LV Output Risk of Surgery in Patients with Depends on severity of pulmonary hypertension and the adequacy of compensatory mechanisms Depends on surgical factors RV Contractility Normal CO Blood pressure RV Coronary perfusion
Surgical Factors Rapid blood loss procedures RV preload Major surgery or blood transfusion Systemic inflammatory response syndrome produces pulmonary vasoconstriction Pulmonary dysfunction Pulmonary embolization Orthopedic procedures Risk of Surgery in Patients with Mortality for non-cardiac surgery with significant PH is reported in the range of 7-50% 70% mortality for Cesarean section in patients with systemic pulmonary pressures 35% mortality for liver transplantation; 80% mortality with mean PAP > 45 mm Hg Risk of Surgery in Modern PH Centers Meyer, Eur Respir J 2013; 41:1302 114 patients undergoing major surgery at 11 PH centers All patients on medications for PAH 43% of patients NYHA class 3 or 4 PAP 45 mm Hg 39% urgent or emergent surgery 82% GA; 18% spinal anesthesia 7 patients (6%) had major complications 4 patients (3.5%) died Risk of Surgery in PH Centers Risk factors for major complications RAP > 7 mm Hg (OR 1.1) 6MWD < 400 m (OR 2.2) Use of vasopressors (OR 1.5) Emergency procedure (OR 2.4) Mortality 15% vs. 2%
The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Preoperative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension Therapy of Treatment of the underlying disease Treatment of right heart failure Pulmonary vasodilator therapy Vasodilators Therapy of Beta-agonists: Alpha-antagonists: Arterial dilators: Venodilators: Balanced dilators: Calcium blockers: Isoproterenol Phentolamine, tolazoline Hydralazine, diazoxide Nitroglycerin Nitroprusside Nifedipine, diltiazem
Inhaled Nitric Oxide The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Preoperative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension Hemodynamic Goals in PH Maintain preload Maintain SVR (systemic afterload) Maintain RV contractility Maintain heart rate and sinus rhythm Avoid increased PVR Anesthetic Techniques General anesthesia Preload, afterload, contractility Neuraxial blocks Sympathetic tone, preload, afterload Regional anesthesia Ideal for peripheral procedures
Induction Techniques Propofol: preload, afterload, contractility Ketamine: PVR (but not if ventilation is maintained) High dose narcotics: No direct effect but respiratory depression ( PaCO 2 ) Etomidate: Ideal agent Maintenance of Anesthesia Nitrous oxide: PVR (?not in kids) High-dose narcotics: Emergence problems Isoflurane/sevoflurane: SVR and PVR proportionally Combined narcotic-volatile agent techniques work well Increasing role for dexmedetomidine Avoid bradycardia Ventilation and PVR The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Preoperative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension
Intraoperative Monitoring Standard ASA monitors Arterial catheter Intraoperative TEE RV function and volume Intraoperative Monitoring Standard ASA monitors Arterial catheter Intraoperative TEE RV function and volume Pulmonary artery catheter Not used for wedge pressure measurement Risk of pulmonary artery rupture Progression of pulmonary hypertension Guide surgical and anesthetic decision making Treatment of systemic hypotension The 7 Steps Recognition of pulmonary hypertension Assessment of severity of pulmonary hypertension Perioperative risk assessment Pre-operative optimization of the patient Choice of anesthetic technique Choice of monitoring Treatment of decompensated pulmonary hypertension Cycle of RV Failure RV Afterload RV Hypertrophy RV Contractility Normal CO PVR RV Output LV Output Blood pressure RV Coronary perfusion
Treatment of RV Failure Molloy, Am Rev Respir Dis 1984; 130:870 RV failure model of pulmonary hypertension from pulmonary embolism Resuscitation with Volume: 0% survival Isoproterenol: 0% survival Norepinephrine: 100% survival RV ischemia RV Decompensation RV coronary flow occurs only in diastole in pulmonary hypertension Increased oxygen consumption Cycle of ischemia and failure Diastole Diastole RV Decompensation Role of the interventricular septum RV LV RV RV LV 20 120 90 70 Systole Systole
Etiologies of Hypotension Decreased preload Decreased contractility CVP PAP CO Decreased SVR or Increased PVR Management of Hypotension Is CVP decreased? Yes Volume Is PAP decreased? Yes Inotropes/ Vasoconstrictors Are there reversible causes of increased PVR? Is cardiac output decreased? Treatment Systemic Inotropes and/or vasoconstrictors Pulmonary vasodilators Management of Hypotension Is CVP decreased? Yes Volume Is PAP decreased? Yes Inotropes/ Vasoconstrictors Are there reversible causes of increased PVR? Is cardiac output decreased? Treatment Systemic Inotropes and/or vasoconstrictors Pulmonary vasodilators Hypoxia Active Pulmonary Vasoconstriction Hypercarbia Acidosis Sympathetic tone Vasoconstrictors
Management of Hypotension Is CVP decreased? Yes Volume Is PAP decreased? Yes Inotropes/ Vasoconstrictors Are there reversible causes of increased PVR? Is cardiac output decreased? Treatment Systemic Inotropes and/or vasoconstrictors Pulmonary vasodilators Systemic Vasoconstrictors Kwak, Anaesthesia 2002; 57:9 27 patients with pulmonary hypertension who developed hypotension following induction of anesthesia Randomized to norepinephrine infusion vs. phenylephrine infusion to increase systolic BP by 50% Phenylephrine failed to increase SBP by 50% in one-third of patients Vasopressin Systemic vasoconstriction via the V1 receptor No pulmonary, renal, cardiac, or cerebral vasoconstriction Pulmonary vasodilation via a NO-dependent mechanism Effective for rescue therapy of PH MANAGEMENT OF HYPOTENSION Is CVP decreased? Yes Volume Is PAP decreased? Yes Inotropes/ Vasoconstrictors Are there reversible causes of increased PVR? Is cardiac output decreased? Treatment Systemic Pulmonary vasodilators vasoconstrictors
MANAGEMENT OF HYPOTENSION Is CVP decreased? Yes Volume Is PAP decreased? Yes Inotropes/ Vasoconstrictors Are there reversible causes of increased PVR? Is cardiac output decreased? Treatment Systemic Pulmonary vasodilators vasoconstrictors Inhaled Postoperative Management Most challenging aspect of the case Emergence issues Dexmedetomidine ICU monitoring Continue chronic pulmonary vasodilator therapy throughout the perioperative period Tips for the Anesthesiologist Risk-benefit analysis before anesthesia Optimize the patient before surgery Maintain outpatient pulmonary vasodilators Avoid vasodepressant drugs Use etomidate for induction; vasopressin for hypotension Avoid pulmonary vasoconstriction Adequate oxygenation and ventilation Avoid high tidal volume ventilation Adequate pain control Avoid treating pulmonary artery pressure in the absence of other indications Call a friend: Rpearl@stanford.edu THANK YOU AND GOOD LUCK! THANK YOU!