Anesthesia for noncardiac surgery in patients with pulmonary hypertension or right heart failure

INTRODUCTION — Pulmonary hypertension and right-sided heart failure present unique challenges and have increased risk for perioperative mortality morbidity. This topic will discuss anesthetic management of patients with PH, right HF, or a combination of these pathologies. Other aspects of perioperative management for these patients are discussed in separate topics:

●(See "Intraoperative management for noncardiac surgery in patients with heart failure".)

●(See "Perioperative management of heart failure in patients undergoing noncardiac surgery".)

●(See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy".)

Anesthetic management of parturients with PH and other high-risk heart disease is discussed separately:

●(See "Anesthesia for labor and delivery in high-risk heart disease: General considerations".)

●(See "Anesthesia for labor and delivery in high-risk heart disease: Specific lesions".)

RISKS OF ANESTHESIA AND SURGERY — Multidisciplinary planning before surgery is necessary due to increased perioperative risk for mortality and morbidity in patients with significant pulmonary hypertension (PH) and right-sided heart failure (HF) [1]. The anesthesiologist should consult with treating physicians (eg, cardiologist or pulmonologist) and the surgeon to ensure that careful consideration has been given to the indications and benefits of surgery with potential risks discussed with the patient and that preoperative hemodynamic optimization has been achieved. In selected cases, these consultants may explore nonsurgical alternatives. Examples include minimally-invasive or interventional radiology procedures, or cancer treatment with chemotherapy or radiotherapy if appropriate. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Procedural risk factors'.)

Pulmonary hypertension — PH is defined as an elevated mean pulmonary arterial pressure (PAP) >20 mmHg at rest [2,3]. PH was previously defined as a mean PAP ≥25 mmHg and most studies of risk associated with PH reflect this older definition. The degree of risk and appropriate management differs with the severity and type of PH. For example, in the treatment of PH due to left heart failure, mild PH is generally managed with diuretics and standard heart failure therapies; the addition of targeted therapy for PH is reserved for selected patients with combined post- and precapillary PH. (See "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults", section on 'Management'.)

Classifications of PH are based on patient function (table 1) and etiology (table 2). The most common etiology of PH is left heart disease. Other causes include pulmonary arterial hypertension (Group 1 PAH), pulmonary embolism, chronic obstructive pulmonary disease (COPD), and interstitial lung disease. (See "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults" and "Treatment and prognosis of pulmonary arterial hypertension in adults (group 1)".)

Patients with asymptomatic or mildly symptomatic PH with preserved cardiac output and only mildly elevated PAP may only require close monitoring in the perioperative period, while those with more substantial disease may need more intensive monitoring and management, preferably by an anesthesiologist with experience caring for such patients. Regardless of etiology, patients with clinically significant PH have increased risk for perioperative mortality and morbidity, including those with mild to moderate PH [1,4-12]. A study of nearly 18,000,000 patients included in an administrative database noted higher mortality after various types of noncardiac surgery in the 143,846 patients with PH compared to those without this diagnosis (4.4 versus 1.1 percent; adjusted odds ratio [aOR] 1.51. 95% CI 1.47-1.55) [12]. Other studies in noncardiac surgical patients at tertiary care centers have reported mortality to be 2 to 10 percent, with higher risk when emergency surgery is necessary [4,6,7,11]. Specific preoperative predictors of mortality in patients with PH include elevated right atrial pressure (>7 mmHg), right ventricular hypertrophy, short six-minute walking distance (≤399 meters), history of pulmonary embolus, perioperative use of vasopressors, major surgery, and long duration of surgery (>3 hours) [4,6,11].

Other perioperative complications reported in patients with PH include nonfatal myocardial infarction (3.2 versus 0.6 percent; aOR 1.49, 95% CI 1.44-1.54 [12]), pulmonary embolism (6.1 versus 0.7 percent; aOR 3.35, 95% CI 3.27-3.44 [12]), cardiogenic shock (0.6 versus 0.1 percent; aOR 2.37, 95% CI 2.20-2.55 [12]), as well as cardiac dysrhythmias, congestive heart failure (CHF), severe hypoxemia, respiratory failure, renal insufficiency, and sepsis [5,7-9,11]. In addition, medication-related complications (eg, anticoagulants and prostanoids) can increase risk of surgical bleeding.

Right-sided heart failure — Right-sided HF is often present in patients with PH, with the most common etiology being left heart disease. A single disease process (eg, myocardial infarction) or concurrent disease processes may affect both ventricles (see "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults"). Other causes of right HF include cardiomyopathy (eg, arrhythmogenic right ventricular [RV] cardiomyopathy), tricuspid regurgitation, pulmonic stenosis, and pulmonic regurgitation.

Pressure and volume overload and/or direct myocardial injury leads to dilatation and increased wall tension, impairment of perfusion, and reduced contractility of the RV, with eventual development of right-sided HF [13]. Patients with severe right HF and/or PH may present with oxygen dependence or other overt signs and symptoms of right-sided volume overload. (See "Approach to diagnosis and evaluation of acute decompensated heart failure in adults", section on 'Differential diagnosis' and "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy".)

Patients with right and/or left-sided HF are at greater risk for mortality and major adverse cardiac events in the perioperative period than those with coronary artery disease. Perioperative risk assessment is discussed elsewhere. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Assessing risk'.)

PREANESTHETIC CONSULTATION

General considerations — The goals of the preanesthetic consultation are targeted assessment of the severity of PH and/or right-sided HF, functional status, and any modifiable factors that would optimize the patient's condition.

Preoperative medical preparation of these patients may be complex [1]. Occasionally, advanced hospitalization may be needed to optimize intravascular volume status, hemodynamic management, or logistical support for vasoactive infusions. For patients with severe PH and right ventricular (RV) dysfunction, necessary surgical procedures are ideally performed in centers with surgical teams, anesthesiologists, cardiologists, pulmonologists, and intensivists with expertise in handling these high-risk patients, including the availability of personnel and equipment to provide RV mechanical circulatory support if necessary [1]. (See 'Ensuring optimal preoperative condition' below.)

History and physical examination — The history is reviewed to assess the patient's symptoms (such as fatigue, dyspnea, chest pain, or syncope), the functional significance of PH (determined by measuring exercise capacity (table 1)), and the patient's New York Heart Association (NYHA) functional class (table 3). Other cardiac, pulmonary, renal, hepatic, and hematologic comorbidities are identified. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Clinical evaluation' and "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy", section on 'Pretreatment evaluation'.)

The physical examination should include assessment of the presence and severity of signs of left- and right-sided HF including assessment of evidence of congestion and an initial assessment of intravascular volume status. Recent changes in the presence or severity of peripheral edema, jugular venous distention, hepatojugular reflux, hepatosplenomegaly, ascites, or tricuspid regurgitation should be noted. If worsened status is detected, the patient's cardiologist is consulted for further management. (See 'Optimal intravascular volume status' below and "Perioperative management of heart failure in patients undergoing noncardiac surgery".)

Preoperative testing — Preoperative tests may be ordered by the consulting cardiologist or pulmonologist in selected patients with PH and/or HF to achieve hemodynamic optimization, depending on the clinical indication, recent prior testing, and the likelihood that such testing might impact decisions regarding perioperative management, timing of the surgical procedure or choice of surgical technique [1,14-17]. For example, preoperative right heart catheterization might be considered when the direct measurement of hemodynamics would be useful to assess risk for elective surgery and the degree of reversibility and responsiveness to therapy such as pulmonary vasodilators. Other noninvasive testing, such as echocardiography, pulmonary function tests, radiographic imaging and arterial blood gas analysis, may be performed to establish a baseline for patients with underlying lung or heart disease. If a diuretic has been chronically administered, serum electrolytes should be checked for abnormalities that may lead to cardiac arrhythmias (eg, hypokalemia) [18]. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Preoperative tests'.)

Obstructive sleep apnea (OSA) may be an underlying cause of hypoxemia that exacerbates PH; thus, screening for OSA should be a routine part of the preoperative evaluation. (See "Surgical risk and the preoperative evaluation and management of adults with obstructive sleep apnea", section on 'Initial assessment'.)

Right heart catheterization accurately measures the hemodynamic parameters and confirms that PH exists, but this invasive procedure is often deferred until advanced therapy is indicated. If available, information from the patient's right heart catheterization is used by the anesthesiologist to guide perioperative interventions (eg, mean central venous pressure [CVP], pulmonary artery pressure [PAP], pulmonary capillary wedge pressure [PCWP], pulmonary vascular resistance [PVR], response to inhaled nitric oxide, a selective acute pulmonary vasodilator, cardiac output [CO], and mixed venous oxygen saturation [SvO₂]) [19,20]. Notably, PH is typically a chronic disease characterized by extensive vascular remodeling. Thus, there is no role for the initiation of an acute pulmonary vasodilator, with the possible exception of parenteral prostanoid during an acute hemodynamic deterioration, with initiation by a clinician with experience using this drug. (See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy", section on 'Definition' and "Pulmonary artery catheterization: Indications, contraindications, and complications in adults", section on 'Patients undergoing high risk surgery'.)

Ensuring optimal preoperative condition — The anesthesiologist and consulting physicians ensure that intravascular volume status, oxygenation, blood pressure (BP), and heart rate (HR) are in an optimal range, treatable factors exacerbating PH or right-sided HF are managed, and essential chronic mediations are continued uninterrupted [1]. Discussions regarding specific preoperative therapies are found in separate topics. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Preoperative management' and "Strategies to reduce postoperative pulmonary complications in adults", section on 'Preoperative strategies'.)

Management of chronic medications — Chronically administered medications to ameliorate PH and the underlying diseases leading to PH and/or right-sided HF are generally continued throughout the perioperative period without interruption [1].

●Chronic pulmonary arterial hypertension (PAH)-targeted therapies – Parenteral, oral, and inhaled chronic PAH-targeted therapies are the mainstay of therapy for patients with Group 1 PAH (eg, due to disorders that are idiopathic, heritable, or due to congenital heart disease, connective tissue disorders, HIV infection, portal hypertension, drugs, or toxins (table 2)), and should be continued without interruption [1]. These chronic PAH-targeted agents include prostacyclin pathway agonists (eg, epoprostenol, treprostinil, iloprost, selexipag), endothelin receptor antagonists (eg, bosentan, macitentan, ambrisentan), and nitric oxide-cyclic guanosine monophosphate enhancers (eg, the phosphodiesterase-5 inhibitors sildenafil and tadalafil, or the guanylate cyclase activator riociguat). (See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy", section on 'Definition' and "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy".)

While discontinuing chronic oral targeted therapy for brief perioperative periods is generally well-tolerated, chronic parenteral therapies should not be discontinued, and an experienced PAH team should assist in their management [1]. For patients receiving continuous parenteral (intravenous or subcutaneous) therapy, any interruption in therapy should be avoided since this may precipitate critical decompensation [1,21,22] (see 'Chronic targeted therapy for pulmonary hypertension: Patient selection' below). Dedicated, reliable intravenous access should be ensured, and the anesthesia provider should be familiar with the medication's pharmacologic actions and delivery mode [18,23-25].

●Medications to manage heart failure – Chronically administered medications to manage right-sided or left-sided HF such as beta blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blocker (ARB) agents, mineralocorticoid receptor antagonists, and digoxin are generally continued, as discussed in separate topics [1]. An ACE inhibitor or ARB can generally be safely administered in the perioperative period. However, since established benefits are from chronic use, brief temporary discontinuation is acceptable when fluid shifts might cause excessive hypotension. Some clinicians administer the evening dose of ACE inhibitor or ARB on the day before surgery (and withhold the dose on the morning of surgery) to avoid intraoperative hypotension. (See "Perioperative management of heart failure in patients undergoing noncardiac surgery", section on 'Preoperative management' and "Perioperative medication management", section on 'Cardiovascular medications'.)

●Diuretics – Chronic diuretic administration is common in patients with PH and/or HF [26]. Administration in the immediate preoperative period (eg, on the morning of surgery) depends on assessment of the patient's intravascular volume status (see 'Optimal intravascular volume status' below).

●Anticoagulant medications – Chronically administered anticoagulants (eg, to treat chronic thromboembolic PH) must be managed according to agent-specific, patient-specific, and procedure-specific considerations, as discussed separately. (See "Perioperative management of patients receiving anticoagulants" and "Anticoagulation for prosthetic heart valves: Management of bleeding and invasive procedures", section on 'Planning for invasive procedures'.)

Optimal intravascular volume status — Patients with RV failure and/or PH have poor tolerance for either intravascular volume overload or reduced preload, and the optimal range for preload is narrow. Patients with fluid retention and hypervolemia due to RV failure may benefit from diuretic therapy, but these agents must be administered cautiously to avoid over-diuresis and hypovolemia. In patients with potential or actual hemodynamic instability, intraoperative invasive monitoring is typically employed to establish and maintain optimal intravascular volume status (eg, central venous catheter [CVC], pulmonary artery catheter [PAC], or transesophageal echocardiography [TEE]) [1,18,27]. (See 'Monitoring' below.)

The RV has anatomical and physiological differences from the left ventricle (LV), and is designed to pump a large volume of blood against a small pressure gradient. Thus, even small elevations in PAP can lead to marked decreases in CO in patients with RV failure [28,29]. Hypervolemia with RV volume overload also causes a leftward shift in the interventricular septum, thereby decreasing LV preload and contributing to the decrease in CO. However, hypovolemia may also result in decreased CO since patients with RV failure are preload-dependent; thus, underfilling of the RV decreases RV stroke volume.

Control of exacerbating factors — In some cases, the cardiologist or pulmonologist may initiate new therapies [1]:

●Continuous oxygen administration. Oxygen therapy is indicated in patients with hypoxemia including those with HF and/or PH (table 4). (See "Treatment and prognosis of pulmonary arterial hypertension in adults (group 1)", section on 'General measures and supportive therapy'.)

●Treatment of exacerbations of lung disease (eg, bronchodilators, inhaled and systemic steroids, respiratory support to relieve hypoxemia and hypercarbia, antimicrobial therapy for acute infection). (See "Strategies to reduce postoperative pulmonary complications in adults", section on 'Preoperative strategies'.)

●Treatment of OSA. with respiratory support devices. (See "Surgical risk and the preoperative evaluation and management of adults with obstructive sleep apnea", section on 'Elective surgery'.)

●Lifestyle modifications in selected patients (eg, exercise, cessation of smoking), if time allows. (See "Pulmonary hypertension due to lung disease and/or hypoxemia (group 3 pulmonary hypertension): Treatment and prognosis", section on 'General measures' and "Treatment and prognosis of pulmonary arterial hypertension in adults (group 1)", section on 'General measures and supportive therapy'.)

●Mechanical circulatory support during the perioperative period in rare cases [1,30-32]. Intra-aortic balloon pump (IABP) counterpulsation provides modest hemodynamic support for refractory left heart failure and is also used as a temporizing measure for acute mitral regurgitation. Other mechanical circulatory assist devices (percutaneous axial and centrifugal pumps and nonpercutaneous centrifugal pumps) were designed to provide greater hemodynamic support than an IABP. Nonpercutaneous centrifugal pumps can be used as an LV assist device (LVAD), RV assist device (RVAD), or biventricular device (BiVAD). Very rarely, venoarterial extracorporeal membrane oxygenation (ECMO) is initiated to bypass the RV by placing the cannulas into the right atrium (or central venous circulation) for venous drainage, and into a systemic artery (eg, the femoral artery) for arterial inflow [30-35]. (See "Short-term mechanical circulatory assist devices".)

Implantable cardioverter defibrillators and pacemakers — Patients with right or left HF frequently have a pacemaker and/or implantable cardioverter defibrillator to manage bradyarrhythmias or tachyarrhythmias, or a biventricular pacemaker to provide cardiac resynchronization therapy [36]. Perioperative management of these devices is discussed in detail separately [37,38]. (See "Perioperative management of patients with a pacemaker or implantable cardioverter-defibrillator".)

Preoperative sedation considerations — Preoperative sedation may be useful to attenuate increases in sympathetic tone due to pain and/or anxiety. Thus, sedatives (eg, midazolam) or opioids (eg, fentanyl) should be administered in very small doses, and are titrated very gradually. It is particularly important to avoid oversedation with consequent hypoventilation in patients with PH or HF, since hypoxemia and/or hypercapnia may acutely increase PVR and exacerbate RV dysfunction. This may result in rapid progression to hemodynamic collapse.

INTRAOPERATIVE MANAGEMENT

General principles

Anesthetic management goals — Anesthetic management goals include avoiding factors that increase baseline pulmonary vascular resistance (PVR), maintaining preload in an optimal range while avoiding fluid overload, and maximizing right ventricular (RV) oxygen supply (ie, RV perfusion and subendocardial blood flow), while minimizing RV oxygen demand (ie, RV afterload, tachycardia) [39]. The failing RV is exquisitely afterload sensitive, so one of the key goals is to maintain pulmonary arterial pressure (PAP) as low as possible to maintain forward flow. Various factors during anesthesia and surgery can precipitate rapid hemodynamic decompensation (figure 1).

The role of monitoring in attaining anesthetic goals is discussed below. (See 'Monitoring' below.)

Choice of anesthetic technique — Choice of anesthetic technique is based on procedure-specific requirements and the likely impact of anesthetic agents and interventions on PVR and RV function. Furthermore, the type of surgical intervention is often modified in these patients. For example, while a laparoscopic approach for thoracoabdominal procedures is less invasive and may be optimal for most noncardiac surgical patients, this may be the higher risk approach for patients with significant PH due to increases in intra-abdominal or intra-thoracic pressure.

●General anesthesia incurs significant risks for precipitation of adverse hemodynamic and respiratory effects [1]. However, many surgical procedures require general anesthesia. (See 'Induction and maintenance of general anesthesia' below and 'Emergence from general anesthesia' below.)

●Peripheral nerve blocks and/or sedation with monitored anesthesia care (MAC) is preferred for more minor surgical procedures when feasible [1]. These techniques are not likely to have significant hemodynamic effects so long as oversedation (with consequent hypercarbia and hypoxemia) is carefully avoided. (See "Overview of peripheral nerve blocks" and "Monitored anesthesia care in adults".)

●Neuraxial anesthesia may be safer, as long as hemodynamic stability can be assured [1]. However, high thoracic epidural or spinal anesthesia may cause an acute reduction in systemic vascular resistance (SVR), resulting in decreased preload, cardiac output, and systemic perfusion pressure that may adversely impact RV perfusion and function, and may also cause bradycardia due to blockade of the cardioaccelerator fibers [40].

If a neuraxial technique is selected, an epidural technique or combined spinal epidural is preferred to spinal anesthesia. The goal is to gradually establish the neuraxial block with very slow titration of the local anesthetic selected for epidural administration (eg, 3 to 5 mL every five minutes), or small incremental doses of bupivacaine for a continuous spinal technique (eg, 3 mg increments), with attainment of the minimum block level necessary to complete the surgical procedure [1]. Fluid management to prevent hypotension during onset and maintenance of neuraxial anesthesia can be particularly challenging in patients with HF and PH. If systemic blood pressure (BP) begins to fall, administration of volume should be judicious, while bolus doses of vasopressors and inotropes (eg, phenylephrine boluses of 40 to 100 mcg, or ephedrine boluses of 5 to 20 mg) are administered. Gentle titration of an infusion of phenylephrine or low-dose vasopressin or norepinephrine infusion are other options (table 5). (See "Overview of neuraxial anesthesia".)

Surgical technique considerations — For patients with PH and/or RV failure, potential adverse effects caused by a laparoscopic approach typically outweigh any advantages compared with an open approach (eg, lesser fluid shift and hemodynamic lability, blood loss, pain, systemic stress) [1]. Increased risks include hypercarbia caused by carbon dioxide (CO₂) insufflation to create a pneumoperitoneum, greater likelihood of hypoxemia due to the pneumoperitoneum and typically steep Trendelenburg positioning, and greater risk of venous embolization of air, thrombi, or tissue matter. Also, RV preload is reduced and RV afterload is increased by the pneumoperitoneum, Trendelenburg position, and potential need for relatively high peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP). Furthermore, hemodynamic monitoring may be challenging since the pneumoperitoneum and positioning may create artifacts and inaccuracies in measured values. Finally, duration of laparoscopic surgery may be prolonged compared with open procedures.

Monitoring

●Standard monitoring – All patients have standard noninvasive monitoring, including electrocardiography (ECG), pulse oximetry (SpO₂), and intermittent noninvasive blood pressure (NIBP) cuff measurements (table 6). We use continuous ECG monitoring with leads II and V₅, with computerized ST-segment trending to detect myocardial ischemia and/or arrhythmias. (See "Anesthesia for noncardiac surgery in patients with ischemic heart disease", section on 'Monitoring for myocardial ischemia'.)

Particular attention is paid to continuous monitoring of the fraction of inspired oxygen (FiO₂) concentration and end-tidal carbon dioxide (ETCO₂) measurements to avoid hypoxemia or hypercarbia, and to mechanical ventilatory parameters to avoid high inspiratory pressures. (See 'Management of ventilation' below and "Basic patient monitoring during anesthesia", section on 'Respiratory system monitoring'.)

●Intra-arterial catheter – An intra-arterial catheter is usually inserted in patients with significant PH and RV dysfunction, unless the surgical procedure is minor [1]. Invasive intra-arterial monitoring is often initiated prior to anesthetic induction. An intra-arterial catheter allows:

•Continuous monitoring of arterial BP, with prompt detection and treatment of hemodynamic perturbations.

•Evaluation of respirophasic variations in the arterial pressure waveform (figure 2), or use of a noninvasive device for CO monitoring. (See "Intraoperative fluid management", section on 'Dynamic parameters to assess volume responsiveness' and "Novel tools for hemodynamic monitoring in critically ill patients with shock", section on 'Cardiac output'.)

•Intermittent blood sampling for arterial blood gas measurements to optimally control partial pressures of arterial oxygen (PaO₂) and carbon dioxide (PaCO₂), as well as measurement of arterial pH.

●Central venous catheter – For major surgical procedures, insertion of a central venous catheter (CVC) provides [1]:

•A reliable intravascular conduit for administration of vasopressor, inotropes, or pulmonary vasodilators.

•The ability to monitor central venous pressure (CVP). Monitoring the trend in CVP values may be helpful for maintaining adequate preload while preventing volume overload, particularly in patients with right-sided HF [41]. Although CVP is a poor predictor of volume responsiveness in most patients [41-46], it provides supplemental data regarding intravascular volume status. Also, new-onset or worsening of tricuspid insufficiency may manifest as an increase in CVP. (See 'Fluid management' below and "Intraoperative fluid management", section on 'Traditional static parameters'.)

●Pulmonary artery catheter – The potential risks and benefits of pulmonary artery catheter (PAC) use should be evaluated for each patient. Although outcome data are lacking, a PAC is often inserted for major surgical procedures for continuous RV pressure monitoring [47], as well as to prevent or recognize exacerbations of PH due to hypoxemia or hypercarbia, hypovolemia due to blood loss, or, conversely, hypervolemia due to fluid overload [1]. Specifically, monitoring hemodynamic parameters with a PAC provides:

•The ability to calculate PVR if required to detect acute changes.

•The ability to monitor trends in CVP, PAP, pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and mixed venous oxygen saturation (SvO₂).

Monitoring these parameters may be helpful to recognize and manage any acute exacerbation of PH and/or RV dysfunction so that appropriate therapies may be initiated, and resulting effects may be assessed. (See 'Hemodynamic management' below.)

●Transesophageal echocardiography – Intraoperative transesophageal echocardiography (TEE) monitoring is often employed in patients with severe PH or RV failure [1,27,48-50]. Baseline measurements include:

•Qualitative evaluation of RV function (movie 1), as well as quantitative assessment of RV function by fractional area change (FAC), measurement of three-dimensional RV ejection fraction (RVEF), measurement of tricuspid annular plane systolic excursion (TAPSE), and the myocardial performance index (MPI). (See "Echocardiographic assessment of the right heart".)

•Qualitative evaluation of left ventricular (LV) function. (See "Intraoperative transesophageal echocardiography for noncardiac surgery", section on 'Ventricular function'.)

•Evaluation of valvular pathology, particularly qualitative assessment of tricuspid valve and pulmonic valve function. (See "Echocardiographic evaluation of the tricuspid valve" and "Echocardiographic evaluation of the pulmonic valve and pulmonary artery".)

•Estimation of systolic or mean PAP [51]. (See "Echocardiographic assessment of the right heart", section on 'Estimation of pulmonary artery systolic pressure'.)

Subsequent intraoperative changes can be rapidly detected with transesophageal echocardiography (TEE) monitoring. Emergency use of TEE is indicated to determine the cause of acute decompensation (eg, due to severe RV or LV dysfunction, pulmonary embolism, or hypovolemia). (See "Intraoperative rescue transesophageal echocardiography (TEE)".)

Induction and maintenance of general anesthesia — Anesthetic agents are selected based on their effects on systemic and pulmonary vascular resistance (table 7). A slow rate of administration and incremental dosing are critically important.

●Induction – A reasonable approach to induction of general anesthesia is use of a short-acting hypnotic (eg, etomidate 0.15 to 0.3 mg/kg) [1], together with a moderate dose of an opioid (eg, fentanyl, 1 to 2 mcg/kg) and/or lidocaine 50 to 100 mg to blunt increases in sympathetic tone during airway manipulation, as well as a muscle relaxant with rapid onset. Maintenance of adequate oxygenation and ventilation is critically important during mask ventilation, laryngoscopy and endotracheal intubation or insertion of a laryngeal mask airway (LMA). (See "Intraoperative management for noncardiac surgery in patients with heart failure", section on 'Induction'.)

●Maintenance – Selection of inhaled anesthetic agents is based on their effects on systemic and pulmonary hemodynamics, although specific data regarding effects on PVR are scant (table 7). Nitrous oxide should be avoided because it can mildly increase PVR, as well as worsen hypoxemia [1]. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Cardiovascular effects'.)

If a total intravenous anesthetic (TIVA) technique is preferred, a balanced anesthetic regimen is typically selected, and may include infusions of a sedative-hypnotic component (eg, propofol 50 to 150 mcg/kg per minute), an opioid (eg, remifentanil 0.05 to 0.3 mcg/kg per minute, fentanyl 1 to 2 mcg/kg per hour, sufentanil 0.5 to 1.5 mcg/kg per hour [or 0.008 to 0.025 mcg/kg per minute] (table 8)), and/or adjuvant agents (eg, dexmedetomidine 0.1 to 0.3 mcg/kg per hour) [52,53]. Whether ketamine can cause an increase in PVR in patients with baseline elevations in PVR, such as those with congenital heart disease, remains controversial. (See "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia'.)

Management of ventilation — Ventilation strategies should balance maintenance of adequate oxygenation and ventilation with the need to avoid lung overdistention [1]. Hypoxemia, hypercarbia, and acidosis should be avoided, since these abnormalities worsen PVR and RV function. Atelectasis and factors that compress extra-alveolar vessels (eg, positioning) decrease functional residual capacity (FRC) with resultant hypoxemia and increased PVR. However, positive pressure ventilation may reduce venous return and right-sided CO, and higher PEEP levels (eg, >8 cm H₂O) may lead to increased PVR and worsening of RV function.

Volume-control (VCV) or pressure-control ventilation (PCV) can be used with an optimal level of PEEP to minimize atelectasis. In patients with decreased lung compliance, PCV may provide better oxygenation; however, as tidal volumes may vary significantly with PCV mode, vigilance in monitoring the minute ventilation is critical to avoid hypoventilation and hypercarbia, which can exacerbate pulmonary hypertension [54-56]. High inspiratory pressures and auto-PEEP are avoided. (See "Mechanical ventilation during anesthesia in adults", section on 'Pressure-controlled ventilation' and "Positive end-expiratory pressure (PEEP)", section on 'Auto (intrinsic) PEEP'.)

Hemodynamic management

Fluid management — RV preload is maintained in a tight optimal range, with avoidance of either intravascular volume overload causing RV distention or hypovolemia causing RV underfilling. If a CVC is in place, CVP is typically maintained at 6 to 10 mmHg in patients with well-controlled chronic right HF or PH. However, the optimal range for RV preload varies and may be higher in some patients, which may be noted in preoperative records of data obtained during right heart catheterization or echocardiography studies. (See 'Optimal intravascular volume status' above.)

Abrupt changes in intravascular volume status are avoided or immediately treated. Invasive hemodynamic monitoring is often useful to detect early changes in preload, allowing immediate initiation of appropriate therapy with avoidance of overtreatment. (See 'Monitoring' above.)

Chronic targeted therapy for pulmonary hypertension: Patient selection — Advanced targeted intravenous or inhaled therapies are aimed at treating pulmonary arterial hypertension (PAH), rather than the etiology, and have an important role for many symptomatic patients with group 1 PAH (table 2). In contrast, use of chronic PAH-targeted therapies in Groups 2, 3, and 5 PH is of unproven value and may cause harm, so such use should be avoided. (See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy", section on 'Definition'.)

Continuation of chronic medications is discussed above [1]. (See 'Management of chronic medications' above.)

Group 1 pulmonary artery hypertension (PAH) — For patients with group 1 PAH who are receiving chronic targeted therapy such as intravenous prostaglandin I₂ (epoprostenol) or iloprost, therapy is continued. (See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy".)

Approved chronic inhaled PAH-targeted therapies are iloprost (administered six to nine times per day) and treprostinil (administered four times per day). These are lung-specific agents that reduce PVR without significant effects on the systemic circulation, have a moderate duration of action, and can be delivered to an intubated patient via a nebulizer [39,57-59]. (See "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy".)

Perioperative increases in PVR that do not appear to be due to hypoxemia, hypercarbia, or thromboembolism may be treated with inhaled nitric oxide (when available) (see "Inhaled nitric oxide in adults: Biology and indications for use"). Nitric oxide is typically delivered by a nitric oxide administration apparatus via an endotracheal tube, but may be delivered noninvasively using nasal prongs or high-flow nasal cannula in a patient who is not intubated [60]. Alternatives include increasing the dose of another acute pulmonary vasodilator (eg, intravenous epoprostenol), as guided by experienced PAH physicians, or administering intravenous milrinone. In some institutions, inhaled prostaglandin I₂ (epoprostenol [Flolan]) is used off-label to treat acute intraoperative increases in PVR, but this agent is very short-acting and requires continuous nebulization.

Since targeted therapies that reduce PVR also decrease systemic BP, doses should be reduced in patients who develop hypotension, and vasopressors are administered in patients with severe or persistent hypotension (see 'Vasopressors and inotropes' below). Invasive hemodynamic monitoring (eg, intra-arterial catheter and PAC) is necessary to assess effects of these agents on both the systemic and pulmonary circulations. (See 'Monitoring' above.)

Group 2 PH (PH due to left heart disease) — Based on the available evidence, chronic PAH-targeted therapies are not indicated for routine use in patients with PH due to left heart disease (PH-LHD). In fact, these agents can precipitate acute pulmonary edema due to increased pulmonary flow into a noncompliant left atrium and ventricle. (See "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults", section on 'Targeted therapy for pulmonary hypertension'.)

For patients with PH-LHD, perioperative diuresis is performed as tolerated to reduce PCWP. If pulmonary vasodilation is necessary, milrinone is typically the preferred systemically administered agent. Intravenous prostanoids are avoided in patients with PH-LHD.

In selected patients with PH-LHD, some clinicians administer inhaled nitric oxide if deemed necessary to maintain perfusion when all of the following criteria are met (see "Inhaled nitric oxide in adults: Biology and indications for use"):

●Preoperative or intraoperative documentation of combined post- and precapillary PH with associated RV dysfunction is available. (See "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults", section on 'Right heart catheterization'.)

●PCWP has been optimized and is low enough to ensure a safety margin for use of nitric oxide. While there are no firmly established hemodynamic thresholds for appropriate or safe use of pulmonary vasodilators, the "20/20/10/5" rule (in which the transpulmonary gradient [TPG] is >20 mmHg, PCWP is <20 mmHg, diastolic pulmonary vascular pressure gradient [DPG] is >10 mmHg, and PVR is >5 Wood units) can serve as a simple checklist when initially considering use of this agent. (See "Pulmonary hypertension due to left heart disease (group 2 pulmonary hypertension) in adults", section on 'Targeted therapy for pulmonary hypertension'.)

●PH is persistent despite normalization of the PCWP.

●There is evidence of a clinical response to chronic PAH-targeted therapy to warrant continued administration.

Vasopressors and inotropes — Treatment of exacerbations of RV dysfunction and/or PH typically requires combinations of the following agents (table 5) [61,62]:

●Vasopressors – Vasopressors (norepinephrine, phenylephrine, and vasopressin) to maintain RV perfusion pressure are the first line of support for RV dysfunction, and are also employed to treat acute decompensation [39,62,63]. The concern with these agents is that while they increase systemic BP and support RV perfusion by increasing SVR, they also increase PVR and RV afterload.

Norepinephrine or vasopressin may reduce the PVR to SVR ratio more successfully than high doses of phenylephrine, which can cause unopposed pulmonary vasoconstriction as well as reflex bradycardia (table 5) [61,64,65]. Low-dose vasopressin infusion actually decreases PVR through release of nitric oxide from the pulmonary vascular endothelium and activation of the V2 receptors in vascular smooth muscle [64,66]. However, the dose-dependent coronary vasoconstrictor effects of vasopressin may produce or exacerbate RV ischemia and contribute to RV contractile dysfunction at higher doses. Thus, use of vasopressin in patients with PH and RV failure is generally limited to a low-dose infusion (eg, 0.03 to 0.07 units/minute) [61,64].

●Inotropes – Inotropes are used to improve the contractility of the RV and LV during the perioperative period include milrinone, dobutamine, dopamine, and epinephrine [18,23,67,68]. Benefits of inotropes depend on the agent:

•Inodilators such as milrinone or dobutamine are typically selected to support RV contractility. Milrinone administration also typically reduces PVR, while dobutamine may improve ventricular-vascular coupling. These agents are often used in combination with vasopressors (eg, norepinephrine, vasopressin) to increase coronary perfusion pressure [61].

•Epinephrine supports the systemic circulation, but increases PVR. Also, its associated tachycardia, proarrhythmic effects, and increased myocardial oxygen consumption may negate its benefits. Thus, epinephrine is typically reserved for severe refractory cardiogenic shock.

•Calcium sensitizers, such as levosimendan, are inodilators that increase myocardial sensitivity to calcium, thereby increasing cardiac contractility, and these agents also open adenosine triphosphate channels in vascular smooth muscle which causes vasodilation. Levosimendan is often used in the perioperative treatment of PH and RV failure in countries where it is available, although consistent evidence of benefit is lacking [69,70].

Treatment of arrhythmias — Arrhythmias should be controlled. Typically, a slower heart rate (eg, 60 to 80 beats/minute) is optimal to improve RV perfusion and filling, and tachycardia is avoided. Ideally, sinus rhythm should be maintained. Arrhythmias such as atrial fibrillation or atrioventricular block are treated immediately as they may lead to hemodynamic decompensation. (See "Intraoperative management for noncardiac surgery in patients with heart failure", section on 'Management of arrhythmias'.)

Acute hemodynamic decompensation — Acute increases in PVR and increases in RV systolic pressure of 30 to 40 percent may cause acute decompensated RV failure [1,61-63]. For example, increased sympathetic tone due to pain and stress, persistent RV ischemia, or new embolic phenomena may acutely increase PVR and RV systolic and end-diastolic pressure, causing myocardial ischemia, RV distention, and septal displacement that affects LV filling, with acutely reduced CO, hypotension, and cardiogenic shock (figure 1). Acute deterioration of oxygenation or is managed by increasing fraction of inspired oxygen content (FiO₂) and changes in ventilator settings as appropriate (eg, careful increases in positive end-expiratory pressure). Causes of poor oxygenation that are unique in the PH population (eg, thrombi, pneumothorax, opening of a patent foramen ovale [PFO] due to volume overload) should be considered. Urgent treatment of the primary cause is critical, and PAH-targeted therapies may be appropriate for selected types of pulmonary hypertension as described above. (See 'Chronic targeted therapy for pulmonary hypertension: Patient selection' above.)

Options for patients refractory to medical therapy include mechanical circulatory support (eg, RV assist device [RVAD], extracorporeal membrane oxygenation [ECMO] [1,30-34]). (See "Short-term mechanical circulatory assist devices".)

Emergence from general anesthesia — Emergence from anesthesia is a critical period with potential hemodynamic and respiratory instability. The goal is a smooth emergence with adequate pain control to prevent abrupt increases in sympathetic tone and RV afterload, as well as adequate oxygenation and ventilation to avoid hypoxia and hypercarbia. A reasonable approach is use of a pressure support (PS) mode of ventilation as the patient awakens, with gradual weaning of this support as anesthetic effects dissipate and the patient recovers normal respiratory mechanics. (See "Maintenance of general anesthesia: Overview", section on 'Transition to the emergence phase'.)

Pain and temperature derangements are treated during and after transfer to the postoperative anesthesia care unit (PACU). Pain or hypothermia typically cause sympathetic stimulation with hypertension and/or tachycardia, increased myocardial oxygen consumption, and exacerbation of myocardial ischemia, particularly if shivering occurs. Hyperthermia also increases heart rate and leads to shivering. (See "Perioperative temperature management", section on 'Postoperative temperature derangements' and "Approach to the management of acute pain in adults".)

POSTOPERATIVE MANAGEMENT — In the immediate postoperative period, control of pain, preload, heart rate, systemic blood pressure, ventilation, and temperature remain critically important [1]. Administration of vasoactive infusions and chronic pulmonary arterial hypertension (PAH)-targeted therapies should not be abruptly interrupted. The patient's chronic regimen for treatment of PH should be reinstated as soon as feasible. For example, oral agents such as sildenafil can be restarted when the patient is hemodynamically stable and can tolerate oral intake, or intravenous sildenafil can be administered if such patients are unable to take oral medications.

Selected patients may require postoperative monitoring in an intensive care unit (ICU). Examples include patients with significant intraoperative hemodynamic instability, hypoxemia or hypercarbia at the end of the procedure, and those who require ongoing infusion or inhalation of an acute pulmonary vasodilator agent. Such patients may need continued controlled mechanical ventilation until cardiopulmonary function has stabilized, as well as sedative-analgesic medications to alleviate pain, dyspnea, and anxiety. (See "Pain control in the critically ill adult patient" and "Sedative-analgesia in ventilated adults: Management strategies, agent selection, monitoring, and withdrawal".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Heart failure in adults" and "Society guideline links: Pulmonary hypertension in adults".)

SUMMARY AND RECOMMENDATIONS

●Perioperative risk – Patients with pulmonary hypertension (PH) and/or right-sided heat failure (HF) have increased risk for perioperative mortality and morbidity. (See 'Risks of anesthesia and surgery' above.)

●Preanesthetic consultation – The goals of the preanesthetic consultation are to ensure that intravascular volume status, oxygenation, blood pressure (BP), and heart rate (HR) are in an optimal range, critically important chronic mediations are continued uninterrupted, and treatable factors exacerbating PH or right-sided HF are managed. (See 'Ensuring optimal preoperative condition' above.)

●Intraoperative anesthetic management

•Anesthetic goals – Anesthetic management goals include avoiding factors that increase baseline pulmonary vascular resistance (PVR), maintaining preload in an optimal range (eg, 6 to 10 mmHg in patients with well-controlled chronic right HF or PH) while avoiding fluid overload, and maximizing right ventricular (RV) oxygen supply (ie, RV perfusion and subendocardial blood flow), while minimizing RV oxygen demand (ie, RV afterload, tachycardia). Various factors during anesthesia and surgery can precipitate rapid hemodynamic decompensation (figure 1). (See 'General principles' above.)

•Technique selection – Choice of anesthetic technique is based on procedure-specific requirements and the likely impact of anesthetic agents and interventions on PVR and RV function. Options include (see 'Choice of anesthetic technique' above):

-Peripheral nerve blocks and/or sedation with monitored anesthesia care (MAC) are typically selected for more minor surgical procedures because of low likelihood of significant hemodynamic effects so long as oversedation (with consequent hypercarbia and hypoxemia) is carefully avoided.

-Neuraxial anesthesia may cause an acute reduction in systemic vascular resistance (SVR), resulting in decreased preload and systemic BP that may adversely impact RV perfusion and function, and may also cause bradycardia due to blockade of the cardioaccelerator fibers. Fluid management in this situation can be particularly challenging. If a neuraxial technique is selected, an epidural technique is preferred to spinal anesthesia, and local anesthetic is titrated slowly to achieve the minimum block level necessary. If systemic BP begins to fall, administration of volume should be judicious, and vasopressor agent(s) are administered.

-General anesthesia incurs significant risks for precipitation of adverse hemodynamic and respiratory effects. Anesthetic agents are selected based on their effects on PVR and SVR (table 7). A slow rate of administration and incremental dosing are critically important. During emergence, adequate pain control to prevent abrupt increases in sympathetic tone and RV afterload is ensured, as well as adequate ventilation and oxygenation to avoid hypoxia and hypercarbia. (See 'Induction and maintenance of general anesthesia' above and 'Emergence from general anesthesia' above.)

•Monitoring – Invasive monitoring is frequently employed (see 'Monitoring' above):

-An intra-arterial catheter is usually inserted in patients with significant PH and RV dysfunction, unless the surgical procedure is minor. This allows continuous monitoring of arterial blood pressure (BP) and respirophasic variations in the arterial pressure waveform (figure 2).

-For major surgical procedures, insertion of a central venous catheter (CVC) provides a reliable intravascular conduit for administration of vasopressor, inotropes, or pulmonary vasodilators. Also, monitoring trending in central venous pressure (CVP) may be helpful for maintaining adequate preload while preventing volume overload in patients with right-sided HF.

-Insertion of a pulmonary artery catheter (PAC) provides the ability to calculate PVR to guide use of acute pulmonary vasodilator therapy, as well as continuous monitoring of pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and mixed venous oxygen saturation (SvO₂), which may be helpful to manage acute exacerbations of RV dysfunction.

-Intraoperative transesophageal echocardiography (TEE) monitoring is often employed to:

Qualitatively evaluate RV function (movie 1). (See "Echocardiographic assessment of the right heart".)

Qualitatively evaluate left ventricular (LV) function. (See "Intraoperative transesophageal echocardiography for noncardiac surgery", section on 'Ventricular function'.)

Evaluate valvular pathology, particularly qualitative assessment of tricuspid and pulmonic valve function. (See "Echocardiographic evaluation of the tricuspid valve" and "Echocardiographic evaluation of the pulmonic valve and pulmonary artery".)

Estimate pulmonary artery systolic pressure. (See "Echocardiographic assessment of the right heart", section on 'Estimation of pulmonary artery systolic pressure'.)

Determine the cause of acute decompensation (eg, due to severe RV or LV dysfunction, pulmonary embolism, or hypovolemia). (See "Intraoperative rescue transesophageal echocardiography (TEE)".)

•Fluid management – RV preload is maintained in a tight optimal range, with avoidance of either intravascular volume overload causing RV distention or hypovolemia causing RV underfilling. Invasive hemodynamic monitoring is often useful to detect early changes in preload, allowing immediate initiation of appropriate therapy with avoidance of overtreatment. (See 'Fluid management' above.)

•Hemodynamic management – Administration of combinations of inotropes and vasopressors (table 5), and/or vasodilators may be necessary to treat increases in PVR, exacerbations of RV dysfunction, or acute hemodynamic decompensation. Advanced intravenous or inhaled chronic PAH-targeted therapies aimed at treating pulmonary arterial hypertension (PAH) itself have an important role for many symptomatic patients with group 1 PAH (table 2). In contrast, use of chronic PAH-targeted therapies in Groups 2, 3, and 5 PH is of unproven value and may cause harm, so such use is generally avoided. (See 'Vasopressors and inotropes' above and 'Chronic targeted therapy for pulmonary hypertension: Patient selection' above and "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy" and "Treatment of pulmonary arterial hypertension (group 1) in adults: Pulmonary hypertension-specific therapy", section on 'Definition'.)

•Surgical technique considerations – Increased risks for laparoscopic surgical approaches include hypercarbia caused by carbon dioxide (CO₂) insufflation to create a pneumoperitoneum, greater likelihood of hypoxemia due to the pneumoperitoneum and typically steep Trendelenburg positioning, and greater risk of venous embolization of air, thrombi, or tissue matter. Also, RV preload is reduced and RV afterload is increased by the pneumoperitoneum, Trendelenburg position, and potential need for relatively high peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP). Furthermore, interpretation of invasive hemodynamic monitoring values may be challenging due to a high likelihood of monitoring artifacts and inaccuracy. (See 'Surgical technique considerations' above.)

●Postoperative management – In the immediate postoperative period, control of pain, preload, HR, systemic BP, ventilation, and temperature remain critically important. Administration of vasoactive infusions and pulmonary vasodilators should not be abruptly interrupted. Selected patients may require postoperative monitoring in an intensive care unit (ICU). (See 'Postoperative management' above.)