Hyperventilation versus standard ventilation for infants in postoperative care for congenital heart defects with pulmonary hypertension

Ventilation modalities in infants with congenital diaphragmatic hernia

Neonates with congenital diaphragmatic hernia are among the more complex patients to support with mechanical ventilation. They have particular features that add to the difficulties already present in the neonatal patient. A ventilation strategy tailored to the patient's underlying physiology rather than mode of ventilation is a crucial issue for clinicians treating these delicate patients.

Does intravenous sildenafil clinically ameliorate pulmonary hypertension during perioperative management of congenital heart diseases in children? - a prospective randomized study

BACKGROUND

Pulmonary hypertension (PHT), if present, can be a significant cause of increased morbidity and mortality in children undergoing surgery for congenital heart diseases (CHD). Various techniques and drugs have been used perioperatively to alleviate the effects of PHT. Intravenous (IV) sildenafil is one of them and not many studies validate its clinical use.

AIMS AND OBJECTIVES

To compare perioperative PaO 2 - FiO 2 ratio peak filling rate (PFR), systolic pulmonary artery pressure (PAP) - systolic aortic pressure (AoP) ratio, extubation time, and Intensive Care Unit (ICU) stay between two groups of children when one of them is administered IV sildenafil perioperatively during surgery for CHDs.

MATERIALS AND METHODS

Patients with ventricular septal defects and proven PHT, <14 years of age, all American Society of Anesthesiologists physical status III, undergoing cardiac surgery, were enrolled into two groups - Group S (IV sildenafil) and Group C (control) - over a period of 14 months, starting from October 2013. Independent t-test and Mann-Whitney U-test were used to compare the various parameters between two groups.

RESULTS

PFR was higher throughout, perioperatively, in Group S. PAP/AoP was 0.3 and 0.4 in Group S and Group C, respectively. In Group S, mean group extubation time was 7 ± 7.34 h, whereas in Group C it was 22.1 ± 10.6. Postoperative ICU stay in Group S and Group C were 42.3 ± 8.8 h and 64.4 ± 15.9 h, respectively.

CONCLUSION

IV sildenafil, when used perioperatively, in children with CHD having PHT undergoing corrective surgery, improves not only PaO 2 - FiO 2 ratio and PAP - AoP ratio but also reduces extubation time and postoperative ICU stay.

Perioperative pharmacological management of pulmonary hypertensive crisis during congenital heart surgery

Pulmonary hypertensive crisis is an important cause of morbidity and mortality in patients with pulmonary arterial hypertension secondary to congenital heart disease (PAH-CHD) who require cardiac surgery. At present, prevention and management of perioperative pulmonary hypertensive crisis is aimed at optimizing cardiopulmonary interactions by targeting prostacyclin, endothelin, and nitric oxide signaling pathways within the pulmonary circulation with various pharmacological agents. This review is aimed at familiarizing the practitioner with the current pharmacological treatment for dealing with perioperative pulmonary hypertensive crisis in PAH-CHD patients. Given the life-threatening complications associated with pulmonary hypertensive crisis, proper perioperative planning can help anticipate cardiopulmonary complications and optimize surgical outcomes in this patient population.

Current trends in paediatric and neonatal ventilatory care -- a nationwide survey

AIM

To assess daily practices in paediatric and neonatal ventilatory care in Finland.

METHODS

All neonatal and paediatric intensive care units in Finland were sent a questionnaire on ventilatory strategies and were offered a 3-month prospective survey.

RESULTS

A total of 96% of units returned the questionnaire, and clinicians agreed on most of the principles of lung-protective ventilation. Seventeen hospitals (94%) joined the prospective survey. On average, 2.3 new ventilation episodes were started daily, and totally 211 episodes were monitored. Pulmonary problems (64%) were the main cause of treatment in neonates and postoperative care (68%) in older children. Synchronized intermittent mandatory ventilation with pressure support was the primary mode in 42% of episodes. Hypocapnia was observed repeatedly in all units. In adult intensive care units, children often received high oxygen fraction, leading to hyperoxia, and they were frequently sedated with propofol, which is not licensed for that purpose. A large proportion of children had only light sedation or no sedation at all. Despite the different strategies and practices, most episodes resulted in a favourable outcome.

CONCLUSION

Most of the principles of lung-protective ventilation have been well accepted by clinicians. More attention should be paid to achieving normocapnia and normoxia and to the correct use of sedatives, especially in units that only occasionally provide paediatric ventilation.

Pediatric acute respiratory failure: areas of debate in the pediatric critical care setting

Pediatric intensive care units across the world care for large numbers of mechanically ventilated infants and children on a daily basis, yet management of these patients is far from standardized. This lack of standardization may be a necessity in certain situations given variation between underlying disease processes, pathophysiology, response to therapy and available resources. However, there are many situations in which similar patients are managed differently across pediatric intensive care units simply because there are a shortage of available data to guide the management of these critically ill infants and children. Thus, a large fraction of pediatric critical care involves a combination of institutional preference, individual experience, opinion and extrapolation of adult data.

Neonatal ventilatory techniques - which are best for infants born at term?

Few studies have examined ventilatory modes exclusively in infants born at term. Synchronous intermittent mandatory ventilation (SIMV) compared to intermittent mandatory ventilation (IMV) is associated with a shorter duration of ventilation. The limited data on pressure support, volume targeted ventilation and neurally adjusted ventilatory assist demonstrate only short term benefits in term born infants. Favourable results of high-frequency oscillatory ventilation (HFOV) in infants with severe respiratory failure were not confirmed in the two randomised trials. Nitric oxide (NO) in term born infants, except in those with congenital diaphragmatic hernia (CDH), reduces the combined outcome of death and requirement for extracorporeal membrane oxygenation (ECMO). In infants with severe refractory hypoxaemic respiratory failure, ECMO, except in infants with CDH, reduced mortality and the combined outcome of death and severe disability at long-term follow-up. Randomised studies with long term outcomes are required to determine the optimum modes of ventilation in term born infants.