Postoperative Management Of Pulmonary Hypertension Research Articles

Evaluation and Management of Pulmonary Hypertension in Noncardiac Surgery: A Scientific Statement From the American Heart Association.

Pulmonary hypertension, defined as an elevation in blood pressure in the pulmonary arteries, is associated with an increased risk of death. The prevalence of pulmonary hypertension is increasing, with an aging population, a rising prevalence of heart and lung disease, and improved pulmonary hypertension survival with targeted therapies. Patients with pulmonary hypertension frequently require noncardiac surgery, although pulmonary hypertension is associated with excess perioperative morbidity and death. This scientific statement provides guidance on the evaluation and management of pulmonary hypertension in patients undergoing noncardiac surgery. We advocate for a multistep process focused on (1) classification of pulmonary hypertension group to define the underlying pathology; (2) preoperative risk assessment that will guide surgical decision-making; (3) pulmonary hypertension optimization before surgery to reduce perioperative risk; (4) intraoperative management of pulmonary hypertension to avoid right ventricular dysfunction and to maintain cardiac output; and (5) postoperative management of pulmonary hypertension to ensure recovery from surgery. Last, this scientific statement highlights the paucity of evidence to support perioperative pulmonary hypertension management and identifies areas of uncertainty and opportunities for future investigation.

Inhaled nitric oxide for the postoperative management of pulmonary hypertension in infants and children with congenital heart disease.

Nitric oxide (NO) is a prevalent molecule in humans that is responsible for many physiologic activities including pulmonary vasodilation. An exogenous, inhaled form (iNO) exists that mimics this action without affecting systemic blood pressure. This therapy has been implemented in the treatment of pulmonary hypertension. This review examines the efficacy of iNO in the postoperative management of infants and children with congenital heart disease (CHD). The original review was published in 2005, updated in 2008 and again in 2014. To compare the effects of postoperative administration of iNO versus placebo or conventional management, or both, on infants and children with CHD and pulmonary hypertension. The primary outcome was mortality. Secondary outcomes included length of hospital stay; neurodevelopmental disability; number of pulmonary hypertensive crises (PHTC); changes in mean pulmonary arterial pressure (MPAP), mean arterial pressure (MAP), and heart rate (HR); changes in oxygenation measured as the ratio of arterial oxygen tension (PaO2) to fraction of inspired oxygen (FiO2); and measurement of maximum methaemoglobin level as a marker of toxicity. In this updated version we extended the CENTRAL search to 2013, Issue 12 of The Cochrane Library, and MEDLINE and EMBASE through to 1 December 2013. The original search was performed in July 2004 and again in November 2007. We included abstracts and all languages. We included randomized and quasi-randomized controlled trials comparing iNO with placebo or conventional management, or both. Trials included only children with CHD requiring surgery complicated by pulmonary hypertension. Two authors extracted data. Data were collected on mortality; number of PHTC; changes in MPAP, MAP, HR, and PaO2:FiO2; and maximum methaemoglobin level. Data on long-term mortality, neurodevelopmental disability, and length of hospital stay were unavailable. We performed subgroup analysis by method of control (placebo or conventional management). We reran the searches to December 2013 and identified three new studies. These three studies did not fulfil our inclusion criteria. Therefore, no new studies were included in this updated review. In total four randomized trials involving 210 participants were included in this review. We observed no differences in mortality (OR 1.67, 95% CI 0.38 to 7.30; P = 0.50); PHTC (OR 0.80, 95% CI 0.15 to 4.18; P = 0.79); changes in MPAP (treatment effect -2.94 mm Hg, 95% CI -9.28 to 3.40; P = 0.36), MAP (treatment effect -3.55 mm Hg, 95% CI -11.86 to 4.76; P = 0.40), HR (treatment effect 0.02 bpm, 95% CI -8.13 to 8.18; P = 1.00), or PaO2:FiO2 (mean difference 17.18, 95% CI -28.21 to 62.57; P = 0.46). There was a significant increase in the methaemoglobin level (mean difference 0.30%, 95% CI 0.24 to 0.36; P < 0.00001) in patients treated with iNO, although levels did not reach toxicity levels. Data from long-term mortality, neurodevelopmental disability, and length of stay were not available. Two trials had a low risk of bias. Very low quality of the evidence was observed considering grading of the outcomes. We observed no differences with the use of iNO in the outcomes reviewed. No data were available for several clinical outcomes including long-term mortality and neurodevelopmental outcome. We found it difficult to draw valid conclusions given concerns regarding methodologic quality, sample size, and heterogeneity.

Use of inhaled iloprost for the management of postoperative pulmonary hypertension in congenital heart surgery patients: review of a transition protocol.

Inhaled nitric oxide (iNO) is considered standard therapy for pediatric postcardiac surgical pulmonary hypertension (PH). Limited data suggest that inhaled iloprost (inIlo), an aerosolized prostacyclin, may be a feasible and more affordable therapeutic alternative. The goal of this study was to determine if significant hemodynamic change or adverse events would occur in postoperative congenital heart surgery (CHS) patients with PH after their transition from iNO to inIlo. This retrospective review investigated CHS patients with postoperative PH (mean pulmonary artery pressure [mPAP] >25 mmHg) between January 1, 2010 and December 31, 2011 who transitioned from iNO to inIlo. By protocol, CHS patients receiving stable doses of iNO were gradually transitioned to inIlo. After full transition, the patients received inIlo every 2 h, with a final dosing range of 1.25-5 μg/dose. Both PAP and systemic arterial pressure (SAP) were invasively measured during the transition period. Seven patients ages 10 days to 1.5 years completed the protocol. Measurements of mPAP (p = 0.27) and systolic PAP (p = 0.25) did not differ between iNO and inIlo therapy alone. No serious adverse events or complications (bleeding or thrombocytopenia) occurred. The ratio of systolic PAP to SAP decreased in all patients receiving inIlo alone (p = 0.03). Pulmonary hypertension in postoperative CHS patients can be managed successfully with inIlo, and the measured hemodynamics with this agent are similar to those observed with iNO. For the management of postoperative PH, inIlo may be a reasonable alternative, thus reducing the need for costly iNO. Larger confirmatory studies would more robustly facilitate its integration into standard care.

ABSTRACT 405

Background and aims: Congenital diaphragmatic hernia is a life threatening anomaly. Aims: We want to present successful management of postoperative pulmonary hypertension by iNO in a newborn with CDH. Methods: Management of postoperative pulmonary hypertension by iNO in a newborn with CDH. Results: A male infant weighing 3000 grams delivered by caesarean section due to fetal distress at 39 gestational weeks. Auscultation of the lungs revealed poor air entry on the left, with a shift of cardiac sounds over the right chest. He was intubated and admitted to NICU because of severe respiratory distress. The first chest X-ray of the patient showed intestinal loops in the left hemithorax with mediastinal shift to right. Therefore, a diagnosis of CDH was confirmed. He was operated on the 2nd day of life. While on conventional ventilation, his oxygen saturation obtained from pulse oxymeter was gradually decreased with high oxygenation index (OI > 30). Echocardiography showed that there was severe pulmonary hypertension (mean pulmonary artery pressure, mPAP=68mmHg). The ventilator mode was changed to high frequency oscillation (HFO) with an initial mean airway pressure of 12 cmH2O, a?P of 28 cmH2O, an oscillation frequency of 8 Hz and 100% oxygen together with 20 p.p.m. iNO. Subsequently, pulmonary hypertension was gradually reduced with OI of <20. The dose of iNO was progressively decreased with no rebounds in mPAP and stopped 8 days from the start. He needed free oxygen for ten days and discharged on the 26th day of surgery. Conclusions: iNO may be useful in the management of pulmonary hypertension developed at early postoperative period.

Safety of surgical pulmonary artery catheters in pediatric patients

Background: This study aims to evaluate the postoperative outcomes of surgical pulmonary artery catheters in pediatric patients and to discuss the safety of these catheters. Methods: Between January 2010 and June 2012, surgical pulmonary artery catheters were implanted in 55 patients (26 boys, 29 girls; mean age 23.7±7.1 months; range 1 to 70 months). A retrospective analysis of the patients for pathology, age, body weight, pulmonary and systemic arterial pressure, extubation time, catheter removal time, the amount of bleeding, mortality and morbidity was performed. Results: The mean body weight of the patients was 9.0±2.8 kg. All patients had preoperative pulmonary hypertension which was equal to systemic pressure. Thirtyseven patients received iloprost intravenous infusion via a pulmonary artery catheter. The mean extubation time was 24.5±16.6 hours, while the mean time for pulmonary artery catheter removal was 45.5±19.6 hours. The mean drainage following catheter removal was 23.7±14.4 mL. None of the patients required any revision due to bleeding. No pulmonary artery catheter-related complication was observed in the patients. Conclusion: Surgical pulmonary artery catheterization is a simple technique which can be used for both continuous pressure monitorization and drug infusion. We conclude that this is a safe and contributing method for an effective management of postoperative pulmonary hypertension in pediatric patients.

Review of Inhaled Nitric Oxide in the Pediatric Cardiac Surgery Setting

Surgical intervention for congenital heart disease (CHD) can be complicated by pulmonary hypertension (PH), which increases morbidity, mortality, and medical burden. Consequently, postoperative management of PH is an important clinical consideration to improve outcomes. Inhaled nitric oxide (iNO) is a widely accepted standard of care for PH and has been studied in the context of cardiac surgery for CHD. However, large randomized, double-blind, placebo-controlled, multicenter clinical trials in pediatric patients are limited. This review will provide an overview of the clinical studies in this setting and will discuss general treatment considerations to facilitate a better understanding of the clinical use of iNO for PH after pediatric cardiac surgery.

The application of inhaled nitric oxide in management of postoperative pulmonary hypertension

Objective To evaluate the effects of inhaled nitric oxide (iNO) in management of postoperative pulmonary hypertension in the patients with congenital heart disease. Methods Thirty-two children with refractory pulmonary hypertension or pulmonary hypertensive crisis after open heart operations for congenital heart disease were treated with iNO. The changes of hemodynamics were observed. Results In iNO therapy group,the mean pulmonary artery pressure(mPAP) decreased from (38.0 ±3.2) mm Hg to (28.0 ±2.1) mm Hg,pulmonary vascular resistance (PVR) decreased from (62.2 ±6.7) kPa/(L·S) to (49.9 ±5.6) kPa/(L·S) ,PaO2/FiO2increased from (67.0 ±30. 1 ) mm Hg to (92. 6 ±25.0) mm Hg,and arterial oxygen saturation increased from 0. 78 ±0. 14 to 0. 84 ±0. 09 respectively. No toxic side effect was observed.Conclusion iNO is effective, safe to reduce pulmonary hypertension. It may play an important role in the treatment of postoperative pulmonary hypertension or pulmonary hypertensive crisis in the patients with congenital heart disease. Key words: Congenital heart disease; Nitric oxide; Pulmonary hypertension

Fundamentals of management of acute postoperative pulmonary hypertension

In the last several years, there have been numerous advancements in the field of pulmonary hypertension as a whole, but there have been few changes in the management of children with pulmonary hypertension after cardiac surgery. Patients at particular risk for postoperative pulmonary hypertension can be identified preoperatively based on their cardiac disease and can be grouped into four broad categories based on the mechanisms responsible for pulmonary hypertension: 1) increased pulmonary vascular resistance; 2) increased pulmonary blood flow with normal pulmonary vascular resistance; 3) a combination of increased pulmonary vascular resistance and increased blood flow; and 4) increased pulmonary venous pressure. In this review of the immediate postoperative management of pulmonary hypertension, various strategies are discussed including medical therapies, monitoring, ventilatory strategies, and weaning from these supports. With early recognition of patients at particular risk for severe pulmonary hypertension, management strategies can be directed at preventing or minimizing hemodynamic instability and thereby prevent the development of ventricular dysfunction and a low output state.

Repair of Tetralogy of Fallot with Absent Pulmonary Valve Syndrome

Tetralogy of Fallot (TOF) with absent pulmonary valve syndrome (APVS) occurs in 5% of patients with TOF. TOF-APVS includes an anterior malalignment ventricular septal defect (VSD) similar to TOF with pulmonary stenosis. The right ventricle is hypertrophied and may contain obstructing muscle bands in addition to infundibular narrowing. The pulmonary annulus is mildly to moderately hypoplastic with vestigial nubbins of nonfunctional myxomatous tissue rather than developed valve leaflets. The size of the main pulmonary artery ranges from normal to aneurysmal depending on the severity of the anomaly, whereas the branch pulmonary arteries are markedly aneurysmal, often two to three times their normal diameters. The hilar portions of the pulmonary arteries may also be dilated. The segmental branches are of normal size and appear as multiple orifices arising from the dilated portion of the artery when viewed from inside the vessel. A patent ductus arteriosus is never present in TOF-APVS. The combination of a VSD, pulmonary insufficiency, and a patent ductus arteriosus would potentially produce physiologic aortic insufficiency: left ventricular output could flow retrograde through the ductus, into the right ventricle, across theVSD,andbackintotheleftventricle.Ithasbeenproposed that the absence of a pulmonary valve influences premature closure of the ductus, or the fetus would not survive. The highly pulsatile flow through the pulmonary arteries may result in the aneurysmal dilation. 1,2 Patients with TOF-APVS can be divided into two groups. The first group presents in the neonatal period with respiratory distress, attributed to compression of the tracheobronchial tree by the aneurysmal pulmonary arteries. These patients require early surgery to avoid morbidity and death from respiratory distress and heart failure. The second group of patients is less symptomatic in infancy and may be identified later in life with symptoms of congestive heart failure, or classic TOF cyanotic spells. These patients can be managed similarly to other patients with TOF and undergo elective repair. There are two major debated issues regarding the surgical management of neonates with TOF-APVS: management of the aneurysmal pulmonary arteries, and placement of a pulmonary valve in the right ventricular outflow tract. Multiple operations have been proposed to address these issues. 3-10 In the operation we describe below, we remove the maximal amount of abnormal pulmonary arterial tissue and place a right ventricular to pulmonary artery homograft conduit. Complete excision of the main and branch pulmonary arteriesremovesalmostallaneurysmaltissue,therebyminimizing any chance of persistent tracheobronchial compression. Use of a homograft places a valve in the pulmonary outflow tract, which simplifies the postoperative management of pulmonary hypertension.

Inhaled Nitric Oxide for the Postoperative Management of Pulmonary Hypertension in Infants and Children with Congenital Heart Disease

Inhaled Nitric Oxide for the Postoperative Management of Pulmonary Hypertension in Infants and Children with Congenital Heart Disease

Anesthetic Consideration Concerning a Congenital Diaphragmatic Hernia in a Patient with a Single Ventricle: A case report

A congenital diaphragmatic hernia is a life threatening condition. It causes pulmonary hypertension with right to left shunting that contributes to severe hypoxemia in neonates. A particulary poor prognosis is predicted if a congenital diaphragmatic hernia is associated with cardiac deformities and pulmonary hypoplasia. We experienced a case of a 3,500 gm female infant with a congenital diaphragmatic hernia and a single ventricle with left pulmonary atresia. Of prime concern was the maintenance of pulmonary vascular resistance, and this was achieved by altering ventilation, inspired oxygen concentration and blood pH. Also postoperative management of pulmonary hypertension is as important as surgical correction of the congenital diaphragmatic hernia. We performed general anesthesia with -fentanyl-isoflurane for correction of diaphragmatic hernia. The fentanyl infusion continued after the operation for blunting of stress responses in the pulmonary circulation. The patient was given a Blalock-Taussig shunt at postoperative day 12.

Pulmonary hypertension in pediatric heart transplantation

Pulmonary hypertension can pose a significant problem in the management of children with congestive heart failure. Assessment of pulmonary artery anatomy, pressures and (when possible) pulmonary vascular resistance is critically important in the evaluation of these children when they are under consideration for heart transplantation. Severe, fixed elevation of the pulmonary vascular resistance is a contraindication to heart transplantation because of concerns of acute post-transplant donor right ventricular failure. However, even modest degrees of pulmonary hypertension can complicate the post-operative management of pediatric heart transplant recipients. This review will provide information regarding the recognition, diagnosis, and pre-operative and post-operative management of pulmonary hypertension in patients under consideration for heart transplantation.

Inhaled nitric oxide in cardiology practice.

Inhaled nitric oxide allows selective pulmonary vasodilatation with rapidity of action. It is effective in the acute post-operative management of pulmonary hypertension in cardiac surgical patients and is also valuable in assessing the pulmonary vasodilator capacity in patients with chronic pulmonary hypertension. This review examines the current role of inhaled nitric oxide in cardiac medicine, discussing issues concerning its administration and toxicity, as well as a summary of clinical studies in cardiac patients. New roles, as a modifier of platelet and leukocyte function, post-thrombolysis and following lung transplantation are described. New agents and alternative therapies, which prolong pulmonary activity, are also discussed.

Surgical Repair of Ventricular Septal Defect in 2085 Pediatric Patients

Of 5587 operations for congenital heart disease that we performed between January 1976 and December 1993, 2085 were for correction of ventricular septal defects. Paramembranous, muscular, and atrioventricular canal types were repaired through a right atrial incision, whereas subpulmonary and conus type defects were repaired through a pulmonary artery incision. Circulatory arrest under deep hypothermia was used for patients under 2 years of age or with body weight of less than 10 kg. There were 48 postoperative deaths. The overall mortality was 2.3% and it was related to the age and weight of the patients. The age at which surgical repair was undertaken depended on the position and size of the defect and the degree of intracardiac shunt. Patients with associated pulmonary hypertension underwent surgery before 2 years of age. Early repair of subpulmonary ventricular defects is recommended to prevent aortic insufficiency resulting from valve prolapse. The keys to successful repair were avoidance of a right ventricular incision, improvement of right ventricular function, and postoperative management of pulmonary hypertension. The operative mortality was reduced from 10.14% in the 1970s to 6.43% in the early 1980s by improvements in surgical procedure and postoperative management with a further reduction to 1.25% in recent years, which we attribute partly to the use of a hollow fiber membrane oxygenator.

Very-low-dose inhaled nitric oxide: A selective pulmonary vasodilator after operations for congenital heart disease

Inhaled low-dose nitric oxide (2, 10, 20 ppm), together with high inspired oxygen concentration (0.80), was administered after corrective operations 13 times to 10 infants (median age 6 months) who were at risk of postoperative pulmonary hypertension because of their congenital heart disease and left-to-right shunt. Inhaled nitric oxide, even in a very low dose (2 ppm), caused selective pulmonary vasodilatation. The pulmonary/systemic artery pressure ratio was a predictor of the response to nitric oxide, with a greater response being seen in those with a high ratio (> or = 0.50). In children with a high pulmonary/systemic pressure ratio, the mean pulmonary vascular resistance index fell by 37% to 42%, accompanied by only a 10% fall in the systemic vascular resistance index but a 14% to 16% rise in mean cardiac index. No toxicity was seen in any subject. This exciting new therapy may prove to be an important adjunct in the management of postoperative pulmonary hypertension in the child with congenital heart disease.

Milrinone and postoperative pulmonary hypertension

C LINICAL EXPERIENCE in both Europe and North America suggests that an increasing number of adult patients presenting for cardiac surgery are at risk of pulmonary hypertension. There are a number of factors responsible for this, not least the increasing age of the surgical patient population, and the fact that reoperation and cardiac surgery in very high risk cases are increasingly being undertaken. There is no doubt that the effective management of perioperative pulmonary hypertension remains a major challenge, but it should not be overlooked that optimizing the state of the pulmonary vasculature, and hence of right ventricular function, may have a significant beneficial effect in patients with not only borderline pulmonary hypertension but severe left ventricular impairment. In this situation right ventricular function may have a critical impact on left ventricular diastolic and systolic performance, and in this sense the treatment of the cardiac surgical patient should focus on more than simple pulmonary hemodynamics. Both physiologic and pharmacologic factors may have a major impact on the pulmonary vasculature. Many of the agents used in current practice are identified in this issue (see Dr Hines’ article). In the experimental setting, it is of course possible to strictly control many of the physiologic factors involved, but in clinical practice and research in humans, many of the factors may only be modified to a limited extent, and so the effectiveness of any drug therapy has to be viewed within the context of the clinical environment under study. In this article the experimental and clinical data currently published on the effects of milrinone on the pulmonary circulation are reviewed, with the aim of identifying any potential role of this important new compound in the management of postoperative pulmonary hypertension.