Perioperative Management of Patients With Pulmonary Hypertension and Right Heart Failure

Introduction:

Pulmonary hypertension, or PH, remains one of the most common comorbid conditions in patients showing up for surgeries. Pulmonary hypertension is a very chronic and progressive disease that is characterized by several clinical manifestations, one of which is an abnormal elevation in the patient’s pulmonary arterial pressure. Pulmonary hypertension is additionally an extremely rare as well as progressive condition with an abnormally elevated pulmonary artery pressure mediated by a range of etiologies. The correct diagnosis of pulmonary hypertension is mostly delayed because of the presentation of several non-specific symptoms that lead to a delay in referral to the respective specialist and their services.

The complexity of a sound treatment necessitates multidisciplinary approaches underpinned by several disease etiologies ranging from managing the underlying condition process to state-of-the-art specialist treatments. At present, treatments are approved for only those patients who display a mean pulmonary arterial pressure of more than or equal to 25 mmHg (millimeters mercury). The severity of pulmonary hypertension is usually classified by pulmonary artery pressure that is anywhere between mild, which ranges from 20 mmHg to 40 mmHg, to severe, which is more than 55 mmHg. Mentioned below are a few of the clinical manifestations of pulmonary hypertension and right heart failure.

• The first examinations are subtle, and the findings present an increase in the intensity of the heart sounds that are related to the pulmonary component, and this may be the only sign.

• As the right side of the heart begins to fail, it will eventually lead to an increased preload with an elevation in the venous pressure.

• Other common findings include a gallop rhythm of the heart that is indicative of fluid overload.

• A holosystolic murmur.

• Tender hepatomegaly.

• Pleural effusion.

• Ascites.

• Lower limb edema.

• Fluid accumulation.

• Elevated right heart pressures.

What Investigations Are Included in the Perioperative Management of Patients With Pulmonary Hypertension and Right Heart Failure?

Signs and symptoms of early pulmonary and cardiac diseases are generally non-specific and thus lead to a delay in a presentation followed by diagnosis and apt treatment. This is the core reason why the initial hospital admissions which are relating to pulmonary hypertension may present with varied symptoms of acute heart failure. Initially, the patient may report dyspnea (shortness of breath) along with palpitations and lethargy because of an imbalance between the systemic oxygen delivery and demand during physical exertion. As the condition progresses, exertional chest pain, which is because of subendocardial hypoperfusion from an elevated intra-cardiac pressure as well as weight gain due to water retention in the lower limbs and the abdomen, can occur. Finally, patients develop exertional syncope due to an inability to maintain cardiac output at a time of high demand. Mentioned below are a few of the investigations that are required in the perioperative management of patients with pulmonary hypertension and right heart failure.

• Electrocardiogram.

• Arterial blood gas.

• A biochemistry panel in order to screen patients for any evidence of right ventricular strain, the presence of any respiratory failure, and any kind of myocardial dysfunction.

• Imaging such as chest x-rays.

• HRCT or high-resolution computed tomography.

• Echocardiography.

• PFT or pulmonary function tests in order to identify patients with severe disorders.

• PAC or pulmonary artery catheterization.

• Hematological investigations.

• Human immunodeficiency virus test.

• Presence of any toxins.

• CTDs or connective tissue diseases.

• Schistosomiasis.

• Cardio-respiratory function.

• CPET or cardiopulmonary exercise testing.

Which Anesthesia Is Best for Perioperative Management of Patients With Pulmonary Hypertension and Right Heart Failure?

Regional anesthesia is one of the safest options for both intra- as well as post-operative management. This is mainly because of a lack of central cardiovascular along with respiratory dysregulation. Several indications include peripheral nerve blockade for both lower and upper limb surgery. There are several advantages of these techniques, such as containing the need for periodic positive pressure ventilation, which will result in higher pulmonary arterial pressure. Caution should be practiced to those patients suffering from severe pulmonary hypertension who are not able to sleep in a supine position for long periods of time and have an anticoagulation status.

What Is the Cardiac Support for Perioperative Management of Patients With Pulmonary Hypertension and Right Heart Failure?

Intraoperative pharmacological therapies in order to control pulmonary pressure are crucial. Treatments for the same are two-fold. Treatments for the maintenance of myocardial perfusion may need a combination of several therapeutic agents. Vasopressors, which include Vasopressin or a decreased dose of Noradrenaline, are considered to be first-line agents that enhance venous return. Inotropic agents are used to increase the contraction of the heart. The use of drugs such as Dobutamine as well as Adrenaline is only limited by the molecule in the body that alters, which may lead to persistent tachycardia and, in turn, impaired myocardial perfusion.

What Is Pulmonary Hypertensive Crisis During the Perioperative Management of Patients With Pulmonary Hypertension and Right Heart Failure?

A pulmonary hypertensive crisis is also called a PH crisis, and it is characterized by an elevated mean arterial pulmonary pressure that is much above the mean systolic arterial pressure. This abnormality is meditated by several underlying conditions that may also include right heart failure as well as systemic hypotension. Management of pulmonary hypertension crisis occurs in two aspects, namely, improved oxygenation and the normalization of acid-base balance. The acute management principles are divided into general measures and pharmacological measures.

• General principles include identifying any possible reasons for acute deterioration and cardiovascular disorder.

• Fluid optimization.

• Measures to maintain a stable sinus rhythm.

• Respiratory optimization.

• Severe acidosis can be improved by plasma alkalization that is done with bicarbonate infusion.

• The preferred first-line agents for an increase in the systemic blood pressure above the mean pulmonary pressure are vasopressor and inotropic agents.

• Drugs that mediate systemic vasoconstriction.

• Drugs that aid in pulmonary vasodilatation followed by nitric oxide release.

• Urgent transplantation along with supportive extracorporeal life support.

Conclusion:

Pulmonary hypertension and right heart failure are two of the most common conditions that require several steps of perioperative management. This can be successfully attributed to a thorough understanding of all the management strategies by the medical team and the team of well-experienced anesthetics.