Use of inhaled nitric oxide for emergency Cesarean section in a woman with unexpected primary pulmonary hypertension

Pregnancy Considerations in the Multidisciplinary Care of Patients with Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a vasoconstrictive disease of the distal pulmonary vasculature resulting in adverse right heart remodeling. Pregnancy in PAH patients is associated with high maternal morbidity and mortality as well as neonatal and fetal complications. Pregnancy-associated changes in the cardiovascular, pulmonary, hormonal, and thrombotic systems challenge the complex PAH physiology. Due to the high risks, patients with PAH are currently counseled against pregnancy based on international consensus guidelines, but there are promising signs of improving outcomes, particularly for patients with mild disease. For patients who become pregnant, multidisciplinary care at a PAH specialist center is needed for peripartum monitoring, medication management, delivery, postpartum care, and complication management. Patients with PAH also require disease-specific counseling on contraception and breastfeeding. In this review, we detail the considerations for reproductive planning, pregnancy, and delivery for the multidisciplinary care of a patient with PAH.

Combined Spinal and Epidural Anaesthesia for Caesarean Section in a Parturient with Severe Primary Pulmonary Hypertension

We describe the management of a parturient with severe primary pulmonary hypertension who underwent caesarean section. A multi-disciplinary approach was used. She was admitted to the intensive care unit perioperatively for invasive monitoring and trial of inhaled nitric oxide. Anaesthesia was provided by combined spinal-epidural block. We discuss controversies about the management of obstetric patients with this rare and serious condition.

Pulmonary arterial hypertension: pathogenesis and clinical management

Pulmonary hypertension is defined as a resting mean pulmonary artery pressure of 25 mm Hg or above. This review deals with pulmonary arterial hypertension (PAH), a type of pulmonary hypertension that primarily affects the pulmonary vasculature. In PAH, the pulmonary vasculature is dynamically obstructed by vasoconstriction, structurally obstructed by adverse vascular remodeling, and pathologically non-compliant as a result of vascular fibrosis and stiffening. Many cell types are abnormal in PAH, including vascular cells (endothelial cells, smooth muscle cells, and fibroblasts) and inflammatory cells. Progress has been made in identifying the causes of PAH and approving new drug therapies. A cancer-like increase in cell proliferation and resistance to apoptosis reflects acquired abnormalities of mitochondrial metabolism and dynamics. Mutations in the type II bone morphogenetic protein receptor (BMPR2) gene dramatically increase the risk of developing heritable PAH. Epigenetic dysregulation of DNA methylation, histone acetylation, and microRNAs also contributes to disease pathogenesis. Aberrant bone morphogenetic protein signaling and epigenetic dysregulation in PAH promote cell proliferation in part through induction of a Warburg mitochondrial-metabolic state of uncoupled glycolysis. Complex changes in cytokines (interleukins and tumor necrosis factor), cellular immunity (T lymphocytes, natural killer cells, macrophages), and autoantibodies suggest that PAH is, in part, an autoimmune, inflammatory disease. Obstructive pulmonary vascular remodeling in PAH increases right ventricular afterload causing right ventricular hypertrophy. In some patients, maladaptive changes in the right ventricle, including ischemia and fibrosis, reduce right ventricular function and cause right ventricular failure. Patients with PAH have dyspnea, reduced exercise capacity, exertional syncope, and premature death from right ventricular failure. PAH targeted therapies (prostaglandins, phosphodiesterase-5 inhibitors, endothelin receptor antagonists, and soluble guanylate cyclase stimulators), used alone or in combination, improve functional capacity and hemodynamics and reduce hospital admissions. However, these vasodilators do not target key features of PAH pathogenesis and have not been shown to reduce mortality, which remains about 50% at five years. This review summarizes the epidemiology, pathogenesis, diagnosis, and treatment of PAH.

Hospital and intensive care unit management of decompensated pulmonary hypertension and right ventricular failure

Pulmonary hypertension and concomitant right ventricular failure present a diagnostic and therapeutic challenge in the intensive care unit and have been associated with a high mortality. Significant co-morbidities and hemodynamic instability are often present, and routine critical care unit resuscitation may worsen hemodynamics and limit the chances of survival in patients with an already underlying poor prognosis. Right ventricular failure results from structural or functional processes that limit the right ventricle’s ability to maintain adequate cardiac output. It is commonly seen as the result of left heart failure, acute pulmonary embolism, progression or decompensation of pulmonary hypertension, sepsis, acute lung injury, or in the perioperative setting. Prompt recognition of the underlying cause and institution of treatment with a thorough understanding of the elements necessary to optimize preload, cardiac contractility, enhance systemic arterial perfusion, and reduce right ventricular afterload are of paramount importance. Moreover, the emergence of previously uncommon entities in patients with pulmonary hypertension (pregnancy, sepsis, liver disease, etc.) and the availability of modern devices to provide support pose additional challenges that must be addressed with an in-depth knowledge of this disease.

Statement on pregnancy in pulmonary hypertension from the Pulmonary Vascular Research Institute

Pregnancy outcomes in patients with pulmonary hypertension remain poor despite advanced therapies. Although consensus guidelines recommend against pregnancy in pulmonary hypertension, it may nonetheless occasionally occur. This guideline document sought to discuss the state of knowledge of pregnancy effects on pulmonary vascular disease and to define usual practice in avoidance of pregnancy and pregnancy management. This guideline is based on systematic review of peer-reviewed, published literature identified with MEDLINE. The strength of the literature was graded, and when it was inadequate to support high-level recommendations, consensus-based recommendations were formed according to prespecified criteria. There was no literature that met standards for high-level recommendations for pregnancy management in pulmonary hypertension. We drafted 38 consensus-based recommendations on pregnancy avoidance and management. Further, we identified the current state of knowledge on the effects of sex hormones during pregnancy on the pulmonary vasculature and right heart and suggested areas for future study. There is currently limited evidence-based knowledge about both the basic molecular effects of sex hormones and pregnancy on the pulmonary vasculature and the best practices in contraception and pregnancy management in pulmonary hypertension. We have drafted 38 consensus-based recommendations to guide clinicians in these challenging topics, but further research is needed in this area to define best practices and improve patient outcomes.

Critical care in pregnancy--is it different?

In the first part of this review, the epidemiology of obstetric critical care is discussed. This includes the incidence of severe morbidity in pregnancy, identification of critically ill and potentially critically ill patients, the incidence of obstetric ICU admissions, the type of critical illness by stage of pregnancy, ICU admission diagnoses, the severity of illness in obstetric ICU patients compared to non-obstetric patients, ICU mortality of obstetric patients, the ICU proportion of total maternal mortality, and the causes of death for obstetric patients in ICU. In the second part, the management of obstetric patients who happen to be admitted to a general ICU is discussed. Rather than focusing on the management of particular obstetric conditions, general principles of ICU management will be discussed as applied to obstetric ICU patients. These include drug safety, monitoring the fetus, management of the airway, sedation, muscle relaxation, ventilation, cardiovascular support, thromboprophylaxis, and radiology and ethical issues.

Pharmacologic therapy for pulmonary arterial hypertension in adults: CHEST guideline and expert panel report

OBJECTIVE

Choices of pharmacologic therapies for pulmonary arterial hypertension (PAH) are ideally guided by high-level evidence. The objective of this guideline is to provide clinicians advice regarding pharmacologic therapy for adult patients with PAH as informed by available evidence.

METHODS

This guideline was based on systematic reviews of English language evidence published between 1990 and November 2013, identified using the MEDLINE and Cochrane Library databases. The strength of available evidence was graded using the Grades of Recommendations, Assessment, Development, and Evaluation methodology. Guideline recommendations, or consensus statements when available evidence was insufficient to support recommendations, were developed using a modified Delphi technique to achieve consensus.

RESULTS

Available evidence is limited in its ability to support high-level recommendations. Therefore, we drafted consensus statements to address many clinical questions regarding pharmacotherapy for patients with PAH. A total of 79 recommendations or consensus statements were adopted and graded.

CONCLUSIONS

Clinical decisions regarding pharmacotherapy for PAH should be guided by high-level recommendations when sufficient evidence is available. Absent higher level evidence, consensus statements based upon available information must be used. Further studies are needed to address the gaps in available knowledge regarding optimal pharmacotherapy for PAH.

[Management of cardiac high risk pregnancy. Caesarean section in a primagravida with cyanotic cardiac defect]

A 37-year-old gravida I with cyanotic heart disease presented for caesarean section in the 31st week of gestation. Caesarean section was performed uneventfully with the patient under epidural anaesthesia accompanied by invasive monitoring. Postoperative echocardiography showed no change in the shunt fraction, volumes or the ventricular function. Every patient with complex comorbidities has to be managed according to individual prerequisites and the experiences and preferences of the team. For such high risk pregnancies regional anaesthesia seems to be a possible option although no clear evidence can be found in the literature.

CO and NO pulmonary diffusing capacity during pregnancy: Safety and diagnostic potential

This paper reviews the scientific evidence for the safety of carbon monoxide (CO) and nitric oxide (NO) inhalation to measure pulmonary diffusing capacity (DL(CO) and DL(NO)) in pregnant women and their fetuses. In eight earlier studies, 650 pregnant women had DL(CO) measurements performed at various times during pregnancy, with a minimum of two to four tests per session. Both pregnant subjects that were healthy and those with medical complications were tested. No study reported adverse maternal, fetal, or neonatal outcomes from the CO inhalation in association with measuring DL(CO). Eleven pregnant women, chiefly with pulmonary hypertension, and 1105 pre-term neonates, mostly with respiratory failure, were administered various dosages of NO (5-80ppm for 4 weeks continuously in pregnant women, and 1-20ppm for 15min to 3 weeks for the neonates). NO treatment was found to be an effective therapy for pregnant women with pulmonary hypertension. In neonates with respiratory failure and pulmonary hypertension, NO therapy improved oxygenation and survival and has been associated with only minor, transient adverse effects. In conclusion, maternal carboxyhemoglobin ([Hb(CO)]) levels can safely increase to 5% per testing session when the dose-exposure limit is 0.3% CO inhalation for <or=3min, and for NO, 80ppm for <or=3min. The risk of late fetal or neonatal death from increased Hb(CO) from diffusion testing is considerably less than the risk of death from all causes reported by the Centers for Disease Control, and is therefore considered "minimal risk".

Pregnancy outcome in patients with complex pulmonary atresia: case report and review of the literature

Pulmonary atresia, a rare and complex congenital heart disease, is characterized by the absence of the central pulmonary artery and by the presence of a ventricular septal defect and aortopulmonary collaterals. Pregnancy reports concerning maternal and offspring outcome after palliative operation or repaired pulmonary atresia are sparse. We report here on the outcome of pregnancy in a woman, aged 36, with complex pulmonary atresia in whom palliative operation had been performed at the age of 23. We review the medical literature on pregnancy course as well as maternal and foetal outcome in cases involving this maternal congenital heart disease.

Anaesthesia for caesarean section in the presence of multivalvular heart disease and severe pulmonary hypertension: a case report

Introduction

Pulmonary hypertension is a rare condition and in combination with pregnancy, it can result in high maternal mortality. Mitral stenosis is one of the complicated cardiac diseases that may occur during pregnancy. In this report, we describe our management of such a case, which was even more difficult in combination with pulmonary hypertension, mitral stenosis, and aortic and tricuspid valve insufficiency requiring emergency caesarean section under general anaesthesia.

Case presentation

A 29-year-old primiparae was presented to the anaesthetic department for an urgent caesarean section with a diagnosis of severe pulmonary hypertension in combination with mitral stenosis. The patient was hospitalized prepartum and received oxygen therapy and anticoagulation with heparin. The patient was monitored during labour and delivery with oximetry and arterial and central venous pressure line. Pulmonary arterial lines were not used due to an increased risk and questionable usefulness. Echocardiography revealed a systolic pulmonary arterial pressure of 75 mmHg, and mitral stenosis, aortic and tricuspid valve insufficiency.

We decided to proceed under general anaesthesia. Anaesthesia was induced with etomidate, and succinylcholine. Dopamine and nitroglycerin infusion was preoperatively started and infusion was also preoperatively continued. Hemodynamic parameters were stable during delivery. Neonatal weight and apgar score were satisfactory. After the delivery of a healthy baby, oxytocin was administered. Surgery was completed uneventfully. During the postoperative period, the patient received furosemide and morphine. As the arterial blood gas analyses were stable and the chest-ray was normal, the patient was extubated postoperatively in the second hour in ICU.

Conclusion

Patients with significant multivalvular heart disease require careful preoperative, multidisciplinary assessment and anesthetic planning before delivery in order to optimize cardiac function during the peripartum period and make informed decisions regarding the mode of delivery and anaesthetic technique.

Anaesthesia and right ventricular failure

Acute right ventricular (RV) failure has until recently received relatively little attention in the cardiology, critical care or anaesthesia literature. However, it is frequently encountered in cardiac surgical cases and is a significant cause of mortality in patients with severe pulmonary hypertension who undergo non-cardiac surgery. RV dysfunction may be primarily due to impaired RV contractility, or volume or pressure overload. In these patients, an increased pulmonary vascular resistance (PVR) or a decreased aortic root pressure may lead to RV ischaemia, resulting in a rapid, downward haemodynamic spiral. The key aspects of 'RV protection' in patients who are at risk of perioperative decompensation are prevention, detection and treatment aimed at reversing the underlying pathophysiology. Minimising PVR and maintaining systemic blood pressure are of central importance in the prevention of RV decompensation, which is characterised by a rising central venous pressure and a falling cardiac output. Although there are no outcome data to support any therapeutic strategy for RV failure when PVR is elevated, the combination of inhaled iloprost or intravenous milrinone with oral sildenafil produces a synergistic reduction in PVR, while sparing systemic vascular resistance. Levosimendan is a promising new inotrope for the treatment of RV failure, although its role in comparison to older agents such as dobutamine, adrenaline and milrinone has yet to be determined. This is also the case for the use of vasopressin as an alternative pressor to noradrenaline. If all else has failed, mechanical support of the RV should be considered in selected cases.

Pregnancy complicated with maternal pulmonary hypertension and placenta accreta

Pregnancy is contraindicated in cases of maternal pulmonary hypertension, a highly morbid disease affecting young women of childbearing age. The rate of heart failure increases gradually with the severity of pulmonary hypertension. In certain instances, the severity of maternal pulmonary hypertension in rheumatic heart diseases can be higher than in congenital heart diseases. Placenta accreta is an important cause of bleeding in the second half of pregnancy and in labor. In severe cases, hysterectomy is the only way to manage the bleeding during cesarean section. A 33-year-old gravida, G2P0AA1, suffering from rheumatic heart disease with mitral valve stenosis and pulmonary hypertension, was referred to our high-risk pregnancy center at 10(+3) weeks of gestation due to lower abdominal pain and brownish vaginal bleeding. She had received 2 mitral valve replacements in Shenzhen, China, at the ages of 22 and 26, respectively. Ultrasound scan of the abdomen at 12(+2) gestational weeks showed that the internal cervix was completely covered with the placenta, and a retroplacental hypoechoic space measuring 35 x 13 mm was observed at the upper posterior margin of the placenta. On color Doppler scan, an area of lacunar lake flow was observed in the hypoechoic space of the placenta and a spiral artery with low blood flow resistance was detected. The pulsation of the placental flow was synchronized with the maternal pulse rate. Team specialists, including neonatologists, pulmonary physicians, pediatric cardiologists, hematologists, anesthesiologists, psychiatrists and social workers, as well as high-risk obstetricians were consulted in an effort to minimize fetal and maternal morbidity and mortality. At 29(+2) weeks, the patient developed preeclampsia and delivered a healthy newborn by cesarean section, the uterus being preserved by square compression sutures. The gravida tolerated the procedures and was discharged in stable condition.

Severe cardiac disease in pregnancy, part II: impact of congenital and acquired cardiac diseases during pregnancy

PURPOSE OF REVIEW

Part II of this review gives an overview of the different maternal cardiac problems during pregnancy and their management, and developments over recent years.

RECENT FINDINGS

Many studies published over the last 5 years provided new insights on different cardiac diseases in pregnancy. Publications discussed in this part of the review on cardiac disease in pregnancy, for example, provide epidemiological data on heart disease during pregnancy in general, and cardiomyopathy and ischemic heart disease in particular. In addition, we discussed the implications of a history of peripartum cardiomyopathy for a subsequent pregnancy, interventional strategies during pregnancy in women with ischemic heart disease, and the role of echocardiography in the evaluation of cardiac disease in pregnancy.

SUMMARY

The prevalence of the different causes of heart disease has shifted towards congenital heart disease by the end of the millennium. In developing countries, relatively rare diseases like rheumatic fever are still common, so these diseases are increasingly 'exported' to developed countries. The group of women with congenital heart disease represents most women with heart disease during pregnancy, followed by rheumatic heart disease. With the exception of patients with Eisenmenger's syndrome, pulmonary vascular obstructive disease, and Marfan's syndrome with aortopathy, maternal death during pregnancy is rare in women with heart disease. Although the risk for mortality is low in pregnant women with preexistent cardiac disease, these women are at increased risk for serious morbidity such as heart failure, arrhythmias, and stroke.

Medical therapy for pulmonary arterial hypertension: ACCP evidence-based clinical practice guidelines

Pulmonary arterial hypertension (PAH) is often difficult to diagnose and challenging to treat. Untreated, it is characterized by a progressive increase in pulmonary vascular resistance leading to right ventricular failure and death. The past decade has seen remarkable improvements in therapy, driven largely by the conduct of randomized controlled trials. Still, the selection of most appropriate therapy is complex, and requires familiarity with the disease process, evidence from treatment trials, complicated drug delivery systems, dosing regimens, side effects, and complications. This chapter will provide evidence-based treatment recommendations for physicians involved in the care of these complex patients. Due to the complexity of the diagnostic evaluation required, and the treatment options available, it is strongly recommended that consideration be given to referral of patients with PAH to a specialized center.

Recognition and management of maternal cardiac disease in pregnancy

Heart disease is a leading cause of maternal death. The aim of this study is to review the most common causes of cardiac disease, highlight factors that should be recognized by the clinician, and address recent advances in the anaesthetic management of these patients. Incipient cardiac disease, including peripartum cardiomyopathy, myocardial infarction and aortic dissection, accounts for approximately one in six maternal deaths. The keys to successful diagnosis and management of incipient disease are: a high index of suspicion, particularly in women with known risk factors for cardiovascular disease; a low threshold for radiological investigations; early cardiology input; and invasive monitoring during labour and delivery. Echocardiography is a safe, non-invasive test, under-used in pregnancy. Management of pregnant women with pre-existing cardiac problems should be undertaken by multidisciplinary teams in tertiary centres. In women with pre-existing cardiac disease wishing to proceed to term, cardiac status must be optimized preoperatively and planned elective delivery is preferable. Vaginal delivery is preferable, and with careful incremental regional anaesthesia is safe in most women with cardiac disease. The presence of adequate systems for early detection, appropriate referral to specialist centres, and timely delivery with multidisciplinary support can minimize the serious consequences of poorly controlled heart disease in pregnancy.

The pregnant cardiac woman

Cardiac diseases are present in 0.5-4% of pregnancies, and they remain a frequent cause of death during pregnancy. Pregnancy per se imposes significant hemodynamic changes, placing a major burden on the cardiovascular system. The early recognition and close follow-up of patients with cardiac diseases will improve maternal tolerance to the cardiovascular burden imposed by pregnancy, promote fetal growth and neonatal survival. Rheumatic heart disease remains the most frequent heart disease in the pregnant population with pulmonary edema as the most frequent complication. Atrial septal defect is the most frequent congenital heart disease in the adult population, whereas tetralogy of Fallot is the most common cyanotic congenital heart disease. An improvement in modern techniques of monitoring, a better understanding of the pathophysiology of cardiac disease, as well as multidisciplinary care has led to a substantial improvement in outcome of the pregnant cardiac patient. Management should be initiated before conception as it will provide optimal clinical conditions and sufficient information on the underlying pathophysiology.