Update on anaesthetic approach to pulmonary hypertension:

A Literature Review on the Anesthetic Management of Pulmonary Arterial Hypertension in Non-cardiothoracic Surgery

Pulmonary hypertension (PH) is characterized by narrowing small pulmonary arteries, escalating pulmonary vascular resistance, and affecting the entire cardiovascular system. Pulmonary arterial hypertension (PAH) represents a subgroup of PH and typically affects one in 20,000 individuals. When treating individuals with PAH for non-cardiothoracic surgery, anesthetic management strategies should be tailored to the individual's specific needs. This literature review assessed the anesthetic management of PAH in non-cardiothoracic surgery. Electronic databases such as PubMed, ScienceDirect, Ovid Medical Literature Analysis and Retrieval System Online (MEDLINE), Cochrane, and Google Scholar were searched using relevant keywords related to PAH, noncardiac surgery, and anesthesia. Reference lists and author names were also investigated. The articles that met the inclusion criteria provided evidence suggesting that preoperative assessment should be comprehensive, hemodynamic goals should be established, anesthesia providers should be familiar with the underlying pathology, and cross-consultations between surgeons and anesthesia providers are essential for achieving satisfactory outcomes. Furthermore, patient care should extend beyond the surgical procedure into postoperative recovery in the post-anesthesia care unit (PACU) or intensive care unit (ICU) setting. In conclusion, it is vital for anesthetic management strategies to accommodate the unique needs of PAH patients to optimize their safety during perioperative care.

Effect of tracheal intubation on postoperative complications in patients with pulmonary hypertension combined with non-cardiothoracic, non-obstetric surgery

Endotracheal intubation can be associated with certain complications in certain group of patients. However, the relationship between endotracheal intubation and postoperative complications is unclear in patients with pulmonary hypertension (PHTN). This study evaluated the relationship between endotracheal intubation and postoperative complications in non-cardiothoracic and non-obstetric surgery patients with PHTN. A secondhand analysis of non-cardiothoracic, non-obstetric procedures was performed on patients with PHTN between 2007 and 2013 in a hospital at the University of Washington. Multivariable logistic regression analyses were used to calculate the adjusted odds ratios to estimate the association between anesthesia and 30-day postoperative complications. Interaction and stratified analyses were conducted according to the American Society of Anesthesiologists score (ASA), smoking, hypertension, and open surgical approach. A total of 573 patients were included in this study, and the mean age was 60.3; 54% were male. In a multivariate regression model for patients with non-cardiothoracic, non-obstetric surgery combined with PHTN, the risk of 30-day postoperative complications was higher in the tracheal intubation group than in patients with non-intubated anesthesia after adjusting for potential covariates (adjusted odds ratio = 2.47; 95% CI, 1.28-4.78). However, there was no significant difference in postoperative mortality between these groups. Statistical analysis showed no interaction between the variables of tracheal intubation and 30-day postoperative complications. In this study, we found that tracheal intubation anesthesia is associated with increased risk of 30-day postoperative complications in PHTN patients undergoing non-cardiothoracic, non-obstetric surgery. Further studies are needed to confirm our findings.

Perioperative Management of Pulmonary Hypertension. a Review

Pulmonary hypertension is a rare and progressive pathology defined by abnormally high pulmonary artery pressure mediated by a diverse range of aetiologies. It affects up to twenty-six individuals per one million patients currently living in the United Kingdom (UK), with a median life expectancy of 2.8 years in idiopathic pulmonary hypertension. The diagnosis of pulmonary hypertension is often delayed due to the presentation of non-specific symptoms, leading to a delay in referral to specialists services. The complexity of treatment necessitates a multidisciplinary approach, underpinned by a diverse disease aetiology from managing the underlying disease process to novel specialist treatments. This has led to the formation of dedicated specialist treatment centres within centralised UK cities. The article aimed to provide a concise overview of pulmonary hypertension’s clinical perioperative management, including key definitions, epidemiology, pathophysiology, and risk stratification.

Effects of cardiopulmonary rehabilitation on pulmonary arterial hypertension: A prospective, randomized study

Objectives

This study aims to investigate the effects of cardiopulmonary rehabilitation (CPR) on cardiopulmonary function, quality of life, depression, and hemodynamic parameters in patients with pulmonary arterial hypertension (PAH) and to compare the efficacy of hospital- and home-based exercise programs.

Patients and methods

Between December 2014 to May 2016, a total of 30 patients with PAH were included in the study. The patients were randomly assigned to either a hospital-based (n=15) or home-based exercise program (n=15). The hospital group was assigned to a cardiac rehabilitation (three days/week, 1 hour/week 50 to 70% maximal oxygen uptake [PvO₂]) program for eight weeks. The home-based exercise group received home exercises alone. Before and after eight weeks of rehabilitation, all patients were evaluated for their functional status (PvO₂), pulmonary function including forced expiratory volume in one sec (FEV1), mL, forced vital capacity (FVC), mL and FEV1/FVC%, quality of life using Short Form-36 (SF-36), depression severity using Beck Depression Inventory, and hemodynamic parameters including left ventricular ejection fraction, right ventricular ejection fraction, left ventricular end-systolic diameter, left ventricular end-diastolic diameter, and systolic pulmonary arterial pressure.

Results

Of the patients, 12 completed the study in each group. There was no statistically significant difference in the functional status, quality of life, depression severity, and hemodynamic parameters after the rehabilitation compared baseline between the groups.

Conclusion

Based on our study results, short-term CPR seems not to be beneficial in patients with PAH. We recommend long-term rehabilitation programs to achieve more benefits from aerobic exercise training in this patient population.

Time course of decompensation after angiotensin II and high-salt diet in Balb/CJ mice suggests pulmonary hypertension-induced cardiorenal syndrome

The genetic background of a mouse strain determines its susceptibility to disease. C57BL/6J and Balb/CJ are two widely used inbred mouse strains that we found react dramatically differently to angiotensin II and high-salt diet (ANG II + Salt). Balb/CJ show increased mortality associated with anuria and edema formation while C57BL/6J develop arterial hypertension but do not decompensate and die. Clinical symptoms of heart failure in Balb/CJ mice gave the hypothesis that ANG II + Salt impairs cardiac function and induces cardiac remodeling in male Balb/CJ but not in male C57BL/6J mice. To test this hypothesis, we measured cardiac function using echocardiography before treatment and every day for 7 days during treatment with ANG II + Salt. Interestingly, pulsed wave Doppler of pulmonary artery flow indicated increased pulmonary vascular resistance and right ventricle systolic pressure in Balb/CJ mice, already 24 h after ANG II + Salt treatment was started. In addition, Balb/CJ mice showed abnormal diastolic filling indicated by reduced early and late filling and increased isovolumic relaxation time. Furthermore, Balb/CJ exhibited lower cardiac output compared with C57BL/6J even though they retained more sodium and water, as assessed using metabolic cages. Left posterior wall thickness increased during ANG II + Salt treatment but did not differ between the strains. In conclusion, ANG II + Salt treatment causes early restriction of pulmonary flow and reduced left ventricular filling and cardiac output in Balb/CJ, which results in fluid retention and peripheral edema. This makes Balb/CJ a potential model to study the adaptive capacity of the heart for identifying new disease mechanisms and drug targets.

Intravenous anesthesia with nitroglycerin inhalation for surgical abortion in a patient with severe congenital heart disease and low oxygen saturation: A case report

INTRODUCTION

Congenital heart disease and pulmonary arterial hypertension are perilous to a gravida for the high morbidity and mortality.

CASE PRESENTATION

We report an extremely rare case of a 27-year-old gravida with congenital heart disease and severe pulmonary arterial hypertension of 115 mmHg. Arterial blood gas analysis revealed her oxygen saturation (SpO2) of 67.8% and oxygen partial pressure of 40.0 mmHg, which were severely low. The patient was diagnosed as having gestation combined with congenital heart disease, severe pulmonary arterial hypertension, and hypoxemia.

INTERVENTIONS

The patient was treated with surgical abortion. The patient was monitored with invasive blood pressure (BP), electrocardiogram (ECG), heart rate, SpO2, and arterial gas analysis as from entry into the operation suite. We performed total intravenous anesthesia with nitroglycerin inhalation. She was returned to the ward at the end of surgery.

CONCLUSION

To our knowledge, this is the first reported case in a gravida with severe heart disease and very low SpO2. Nitroglycerin inhalation may provide dilation of the pulmonary artery, reduction of pulmonary artery pressure, and improvement of oxygenation. Our case report may provide alternative regimen to anesthesia practitioners in similar circumstances.

Anaesthetic management of breast surgery in a patient with Eisenmenger syndrome

Eisenmenger syndrome (ES) is a complex combination of cardiovascular abnormalities defined as pulmonary hypertension with investment or bidirectional flow through an intracardiac or aortopulmonary communication, usually secondary to a congenital heart disease not resolved promptly. It carries a significant risk of perioperative mortality, with an incidence close to 30% for non-cardiac surgery. We report the anaesthetic management in a ES patient undergoing breast surgery, which was successfully performed under general anaesthesia combined with thoracic analgesic blocks. The main pathophysiological implications of this syndrome are discussed, emphasizing the importance of appropriate preoperative evaluation with thorough assessment of associated risks, careful intraoperative management, and postoperative care, which should be initially performed in a critical care unit. The need to individualize and tailor the choice of drugs and anesthetic technique to the hemodynamic condition of the patient and the surgical procedure is highlighted.

Perioperative management of patients with severe pulmonary hypertension in major orthopedic surgery: experience-based recommendations

Introduction: It is known that pulmonary hypertension is associated with worse outcome in both cardiac and non-cardiac surgery. The aims of our retrospective analysis were to evaluate the outcomes of our patients with pulmonary hypertension undergoing major orthopedic surgery and to give experience-based recommendations for the perioperative management.

Material and methods: From 92 patients with pulmonary hypertension undergoing different kinds of surgical procedures from 2011–2014 in a tertiary academic hospital we evaluated 16 patients with major orthopedic surgery for perioperative morbidity and mortality.

Results: Regarding the in-hospital morbidity and mortality, one patient died postoperatively due to pulmonary infection and right heart failure (6.25%) and 6 patients suffered significant postoperative complications (37.5%; bleeding = 1, infection = 1, wound healing deficits = 3; dysrhythmia = 1).

Conclusion: Our data show that major orthopedic surgery is feasible with satisfactory outcome even in cases of severe pulmonary hypertension by an individualized, disease-adapted interdisciplinary treatment concept.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Perioperative management in patients with pulmonary hypertension

Patients with pulmonary hypertension (PH) are being encountered more commonly in the perioperative period and this trend is likely to increase as improvements in the recognition, management, and treatment of the disease continue to occur. Management of these patients is challenging due to their tenuous hemodynamic status. Recent advances in the understanding of the patho-physiology, risk factors, monitoring, and treatment of the disease provide an opportunity to reduce the morbidity and mortality associated with PH in the peri-operative period. Management of these patients requires a multi-disciplinary approach and meticulous care that is best provided in centers with vast experience in PH.

In this review, we provide a detailed discussion about oerioperative strategies in PH patients, and give evidence-based recommendations, when applicable.

Clinical and molecular genetics of the phosphodiesterases (PDEs)

Cyclic nucleotide phosphodiesterases (PDEs) are enzymes that have the unique function of terminating cyclic nucleotide signaling by catalyzing the hydrolysis of cAMP and GMP. They are critical regulators of the intracellular concentrations of cAMP and cGMP as well as of their signaling pathways and downstream biological effects. PDEs have been exploited pharmacologically for more than half a century, and some of the most successful drugs worldwide today affect PDE function. Recently, mutations in PDE genes have been identified as causative of certain human genetic diseases; even more recently, functional variants of PDE genes have been suggested to play a potential role in predisposition to tumors and/or cancer, especially in cAMP-sensitive tissues. Mouse models have been developed that point to wide developmental effects of PDEs from heart function to reproduction, to tumors, and beyond. This review brings together knowledge from a variety of disciplines (biochemistry and pharmacology, oncology, endocrinology, and reproductive sciences) with emphasis on recent research on PDEs, how PDEs affect cAMP and cGMP signaling in health and disease, and what pharmacological exploitations of PDEs may be useful in modulating cyclic nucleotide signaling in a way that prevents or treats certain human diseases.

Anaesthetic management of hip arthroplasty in an individual with trisomy 21 and Eisenmenger's syndrome

A 49-year-old man with trisomy 21 and Eisenmenger's syndrome presented for hip arthroplasty. Eisenmenger's syndrome is defined by the presence of obstructive pulmonary vascular disease secondary to long-standing left-to-right shunt causing pulmonary hypertension, eventually leading to shunt reversal in to right-to-left direction. Patients with Eisenmenger's syndrome pose a significant perioperative risk because of the physiological alterations induced by anaesthetic agents. The choice of anaesthetic technique in these patients is therefore not straightforward. A successful outcome was achieved with general anaesthesia supplemented with nerve blocks.

Perioperative anesthesiological management of patients with pulmonary hypertension

Pulmonary hypertension is a major reason for elevated perioperative morbidity and mortality, even in noncardiac surgical procedures. Patients should be thoroughly prepared for the intervention and allowed plenty of time for consideration. All specialty units involved in treatment should play a role in these preparations. After selecting each of the suitable individual anesthetic and surgical procedures, intraoperative management should focus on avoiding all circumstances that could contribute to exacerbating pulmonary hypertension (hypoxemia, hypercapnia, acidosis, hypothermia, hypervolemia, and insufficient anesthesia and analgesia). Due to possible induction of hypotonic blood circulation, intravenous vasodilators (milrinone, dobutamine, prostacyclin, Na-nitroprusside, and nitroglycerine) should be administered with the greatest care. A method of treating elevations in pulmonary pressure with selective pulmonary vasodilation by inhalation should be available intraoperatively (iloprost, nitrogen monoxide, prostacyclin, and milrinone) in addition to invasive hemodynamic monitoring. During the postoperative phase, patients must be monitored continuously and receive sufficient analgesic therapy over an adequate period of time. All in all, perioperative management of patients with pulmonary hypertension presents an interdisciplinary challenge that requires the adequate involvement of anesthetists, surgeons, pulmonologists, and cardiologists alike.