Effect of early adjunctive use of oral sildenafil and inhaled nitric oxide on the outcome of pulmonary hypertension in newborn infants. A feasibility study.

INTRODUCTION: Inhaled nitric oxide (iNO) is the standard therapy for infants with persistent pulmonary hypertension of the newborn (PPHN). Recently, sildenafil has been evaluated as an alternative or adjunctive pulmonary vasodilator. OBJECTIVE: To assess the effectiveness of adding sildenafil as an early adjunctive therapy together with iNO when treating newborns with PPHN and/or hypoxemic respiratory failure. METHODS: This is a randomized placebo trial on newborns with gestational age > 34 weeks, postnatal age < 48 hours, and diagnosed with PPHN (oxygen index (OI) ≥ 20). Newborns were randomized to two groups: Group A- received oral sildenafil and iNO, and group B- received placebo and iNO. Initial and follow up echocardiography were performed over 14 days period. RESULTS: A total of 24 newborns were recruited; 13 of them received sildenafil in addition to iNO and 11 received iNO and placebo. The most common causes of PPHN were meconium aspiration syndrome, pneumonia, and RDS. At the starting point, OI was marginally higher in the intervention group without statistical significance (29 vs 28). There were no differences between the two groups regarding surfactant administration, incidence of pneumothoraces, and the underlying causes of PPHN. Sildenafil or placebo treatment started within 12 hours after starting iNO (8 vs 6 hours). CONCLUSION: Early use of oral sildenafil next to iNO in cases of PPHN was tolerated well by newborns and it did not show significant adverse effects. Further studies with a larger sample size is needed to assess its effecacy.

Sinus node dysfunction after intraatrial lateral tunnel and extracardiac conduit fontan procedures.

This study compares the effects of two techniques for the Fontan procedure-intraatrial lateral tunnel (IALT) and extracardiac conduit (ECC) -on sinus node dysfunction. Between January 1992 and December 1998, 54 patients underwent a total cavopulmonary connection Fontan procedure. Of these, 36 had follow-up 24-hour Holter recordings, and they constitute the population for this study. The 24-hour Holter recordings were performed between January 1998 and March 1999 and were evaluated for sinus node dysfunction and atrial tachycardia. Clinical follow-up (18 +/- 11 months for the IALT group vs 34 +/- 19 months for the ECC group; p = 0.002) and surface electrocardiograms were also reviewed. Among the 36 patients, 19 had an IALT and 17 had an ECC Fontan procedure. The incidence of sinus node dysfunction was 4/19 (21%) in the IALT group and 10/17 (59%) in the ECC group (p = 0.04). No patient from either group had an identified episode of atrial tachycardia. No permanent pacemaker was placed in the IALT group, whereas three were placed in the ECC group, all for sinus node dysfunction. In summary, patients with both IALT and ECC had an important incidence of sinus node dysfunction. The incidence of sinus node dysfunction was higher in the ECC group, which may have been due to longer follow-up in this group. Atrial tachycardia was not observed in either group. Although the IALT group had less sinus node dysfunction than the ECC group and appeared to require less permanent pacing, these data may be too limited to serve as the criteria for choosing between these two techniques for performing the Fontan procedure.

Reference values of common blood chemistry analytes in healthy population of Rawalpindi-Islamabad area.

The reference values of common blood chemistry analytes in healthy population, aged newborn to 80 years, of Rawalpindi Islamabad area were determined at AFIP, Rawalpindi. A total of 2115 healthy subjects, 1206 males and 909 females, were included in the study. Plasma glucose was analysed by GOD/POD, serum cholesterol by CHOD/PAP, triglycerides by GPO/PAP, urea by urease/GLDH, creatinine by Jaffe' rate reaction, uric acid by uricase, total bilirubin by Jendrassik and Grof, total protein by biuret, alanine transaminase (ALT) by optimized IFCC and alkaline phosphatase (AP) by optimized DGKC method. The between batch CVs of all the parameters were within acceptable quality goals. The reference values were calculated using 2.5 and 97.5 percentiles as lower and upper limits (95% CI). In healthy adult males the reference values were: fasting plasma glucose, 3.6-6.0 mmol/l; serum cholesterol; 3.2-6.6 mmol/l; triglycerides, 0.6-2.3 mmol/l; urea, 2.8-6.4 mmol/l; creatinine, 65-132 umol/l; uric acid, 164-430 umol/l; total bilirubin, 5-18 umol/l; total protein, 57-83 g/l; ALT, 15-45 U/l and AP, 185-620 U/l. The values in adult females, children and elderly subjects were slightly different than adult males. The reference values of our population show mild to moderate differences from the other Asian, European and American populations. It is recommended that reference values of different biochemical investigations should be established in various areas of Pakistan to make appropriate use of such investigations.