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 PaO2 – FiO2 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 PaO2 – FiO2 ratio and PAP – AoP ratio but also reduces extubation time and postoperative ICU stay.

Intraoperative autologous blood donation and retrograde autologous priming for cardiopulmonary bypass : a safe and effective technique for blood conservation.

Haemodilution resulting from crystalloid priming of the cardiopulmonary bypass (CPB) circuit is one of the important reasons for blood transfusion in cardiac surgery, especially in patients with low body surface area (BSA). A prospective study was performed to investigate the technique of intraoperative blood donation (IAD) and retrograde autogous priming (RAP) to limit haemodilution and transfusion requirements. Forty patients with low BSA (<1.7m2) undergoing primary valvular cardiac surgery were assigned to either RAP group or a control group (C). The RAP group (n=20) was subjected to IAD by collecting a calculated volume of blood (272+/-44.3 mL) after induction of anaesthesia. Prior to initiation of CPB the prime volume was reduced by discarding some of it and the CPB reservoir was filled retrogradely through the aortic cannula draining 482+/-78.4 mL of blood. In group C (n=20) only IAD was carried out collecting 295.0+/-62.6 mL of blood. Anaesthetic technique was similar in both groups. Strict transfusion thresholds were observed. There were no significant difference between the groups with respect to baseline characteristics, BSA, type of procedure, perfusion technique and haematologic profile. The haematocrit on CPB was significantly higher in the RAP group as compared with group C (24.2+/-1.3% and 22.1+/-2.5% respectively, p=0.009). Transfusion of allogenic blood during and after surgery was significantly lower in the RAP group (143.6+/-117mL) versus 405.2+/-358.1mL in group C (p=0.02). Postoperative chest tube drainage was 218+/-67.4 mL in the RAP group and 300+/-191 mL in group C which was not significantly different (p=0.18). The technique of intraoperative autologous donation and retrograde priming is simple, safe and cost effective procedure for blood conservation in patients with small BSA undergoing primary valvular surgery.