Effect of Clinician-directed Technical Specifications on Entrance Skin Doses in Neonates

Objectives: To compare the entrance skin doses (ESD) before and after implementation of a radiation safety policy in neonates (RSN), which focused on clinician-directed technical specifications on the digital X-ray machine. Methods: Prospective observations included two sets of X-rays: Before (BRSN) and after (ARSN) implementation of RSN (documented indication for Xray/expected posttest findings, settings of 40 kVp, 0.5 mAs, film-focus distance 100 cm, gonadal-shield, optimal collimation, and post-shoot image-enhancement). Results: 33 and 32 X-rays were analyzed in respective groups. Mean (SD) of calculated and machine-quantified ESD (µGy/m2) was higher in BRSN group as compared to ARSN group (P <0.001). All ARSN X-rays were interpretable for expected post-test findings. Conclusion: Clinicians’ cognizance of ability to make consequential bedside technical specifications, can reduce ESD without affecting interpretability. These single observations could have a larger impact in sick neonates, where multiple X-rays are done.

Cardiorespiratory Adverse Events after First Vaccination in Preterm Neonates With Gestational Age ?30 Weeks

Objectives: To document the adverse cardiorespiratory events following first routine immunization in preterm neonates. Methods: We retrieved records of neonates with gestational age ?30 weeks, and included those who developed cardiorespiratory events after first vaccines before discharge. Our Unit’s protocol is to administer Bacillus Calmette-Guerin (BCG), hepatitis B vaccine to those discharged at <8 weeks postnatal age. Hexavalent, BCG, pneumococcal vaccine and rotavirus vaccines are given at 8 weeks of age, if hospital stay is predicted to be longer. Unit compliance to vaccination administration at appropriate ages were also measured. Results: Data of 161 neonates ?30 weeks (17.4% <27 week) who completed care in the unit was studied. Cardio-respiratory adverse events were reported in 21(13.7%). None of these required initiation of invasive ventilation. High flow nasal cannula therapy and caffeine restart were required for these events in 14 (9.3%) and 6 (3.9%) neonates, respectively. Lower gestational age, bronchopulmonary dysplasia and sepsis were significant risk factors on univariate analysis. On multivariate analysis, continued need for respiratory support at 4 weeks of age (P=aOR 14.5 (95% CI 5-59.1) was the only independent risk factor for post-vaccination cardiorespiratory adverse events. Of 38 who were not vaccinated at recommended ages by unit policy, 25 were missed opportunities, the rest were deemed unstable for vaccinations at that age by the clinical team. Conclusion: Adverse cardiorespiratory events were uncommon after first vaccinations in very preterm neonates. Administering vaccines in this group before discharge would allow monitoring for these events, especially for those who require long-term respiratory support.

Incidence of Metabolic Bone Disease After Implementation of Bone Protective Nutritional Strategies: A Prospective Cohort Study

Background: Metabolic bone disease (MBD) is a morbidity of multifactorial etiology with a high incidence in very preterm infants. We planned to study the incidence of MBD after implementation of bone health focussed nutritional strategy (BNS) in those <30 weeks gestation at birth. Methods: This prospective cohort study including preterm newborns (<30 weeks) who received nutrition that incorporated (a) Early initiation of intravenous potassium phosphate; (b) Early enteral supplementation with multicomponent human milk fortifier at enteral feed tolerance of 40 mL/kg/day feeds itself; and (c) Weekly phosphorus measurements with optimization of enteral intakes. Incidence of MBD at 4 weeks of postnatal age and beyond were analyzed. Other relevant safety and clinical outcomes were measured. Results: Of the 67 included neonates receiving BNS, 20.9% were classified as MBD. There was a low rate of hyperphosphatemia (4.5%) and hyperkalemia (2.9%). Full enteral feeds were achieved by median (IQR) of 6 (5,7) postnatal days. Conclusion: In preterm newborns (24-30 weeks) MBD incidence was 20.9% after BNS was implemented. Intravenous potassium salt of phosphorus and early use of HMF were safe and feasible.

Pericardial Tamponade in a Newborn Following Umbilical Catheter Insertion.

We present a case of cardiac tamponade following umbilical venous catheterization in a neonate, an uncommon, yet potentially fatal complication. Timely diagnosis by echocardiography and urgent pericardiocentesis proved lifesaving.

Salt wasting disorder in the newborn.

The clinical presentation of pseudohypoaldosteronism (PHA) mimics congenital adrenal hyperplasia (CAH). Poor response of the dehydration and electrolyte abnormalities to steroid therapy should make one suspect PHA. The treatment is supportive in the form of salt replacement and sodium resonium. We report a case of PHA that presented as salt wasting on the second day of life, initially appearing like CAH. The baby responded well to sodium resonium and salt replacement.

Inhibitory effect of sildenafil on gastrointestinal smooth muscle: role of NO-cGMP transduction pathway.

Nitric oxide (NO) is an important neurotransmitter in the gut and has been demonstrated to be a key physiological mediator of non-adrenergic non-cholinergic (NANC) relaxation of gastrointestinal smooth muscle. In the present study the effect of PDE 5 inhibitor sildenafil on the gastrointestinal function (gastric emptying and intestinal transit) has been demonstrated in mice. Sildenafil (0.5-2 mg/kg, po) did not alter the percent gastric emptying however, in higher doses (5, 10 and 30 mg/kg, po) it inhibited the gastric emptying. On acute administration (0.5-5 mg/kg, po) it did not alter the intestinal transit but in higher doses (10 and 30 mg/kg, p.o.) delayed the intestinal transit. Further, the inhibitory effect of sildenafil was significantly blocked by L-NAME (10 mg/kg, ip), a non-selective NOS inhibitor and methylene blue (1 mg/kg, ip), a guanylate cyclase inhibitor. These findings suggest the participation of NO-cGMP transduction pathway in the inhibitory effect of sildenafil (higher doses) on the gastrointestinal smooth muscles and its potential application in patients with nutcracker oesophagus, hypertensive lower oesophageal sphincter (LOS), achalsia and diabetic gastroparesis or colitis where there is a loss of nNOS.

Infantile cortical hyperostosis.

Infantile cortical hyperostosis (Caffey disease) is characterized by radiological evidence of cortical hyperostosis, soft tissue swellings, fever and irritability. We report a case of Caffey disease highlighting its presentation as pyrexia of unknown origin, appearance on radionuclide bone scintigraphy and our unsatisfactory experience of treating it with Ibuprofen, a prostaglandin inhibitor.

Modulatory effect of diclofenac on antispasmodic effect of pitofenone in cholinergic spasm.

Biliary, ureteric and intestinal colic are extremely common clinical conditions associated with smooth muscle spasm. In the present study, antispasmodic activity was carried out against acetylcholine (10-640 ng/ml)-induced contractions on guinea pig ileum. Acetylcholine (10-640 ng/ml) induced concentration-dependent contraction of smooth muscle. Diclofenac, in varying concentration (9.4 x 10(-5) mol/l and 14.1 x 10(-5) mol/l) shifted the concentration response curve of acetylcholine to the right without suppressing the maximal response. However, in higher concentration diclofenac (18.9 x 10(-5) mol/l) blocked the response in an unsurmountable fashion. Further, analgin (11.09 x 10(-5), 16.63 x 10(-5) and 22.18 x 10(-5) mol/l) in equimolar concentrations did not alter the concentration response curve of acetylcholine, but in higher concentration analgin (44.36 x 10(-5) mol/l) also blocked the response in an unsurmountable fashion. Pitofenone (2.5 x 10(-6) mol/l) also, shifted the concentration response curve of acetylcholine to right in a parallel fashion with no change in maximal response. The present study confirms the potent antispasmodic activity of diclofenac-pitofenone combination in comparison to analgin-pitofenone in molar equivalent concentration (in comparison to diclofenac) against acetylcholine-induced contractions of guinea pig ileum.

Cholinergic-NO-cGMP mediation of sildenafil-induced antinociception.

Acetylcholine and cholinomimetic agents with predominant muscarinic action are known to increase the concentration of cGMP by activation of nitric oxide signaling pathway in the nociceptive conditions. The present study was aimed to investigate the NO-cGMP-PDE5 pathway in nociceptive conditions in the experimental animals. Nociceptive threshold was assessed by acetic acid-induced writhing assay (chemonociception) or carrageenan-induced hyperalgesia. Sildenafil [1-5 mg/kg, ip, 50-200 microg/paw, intraplantar (ipl)] produced dose dependent antinociception in both the tested models. Coadministration of acetylcholine (50 mcg/paw, ipl) or cholinomimetic agent, neostigmine (0.1 mcg/kg, ip and 25 ng/paw, ipl) augmented the peripheral antinociceptive effect of sildenafil. This effect was sensitive to blockade by L-NAME (20 mg/kg, ip, 100 microg/paw, ipl), a non-selective NOS inhibitor and methylene blue (1 mg/kg, ip), a guanylate cyclase inhibitor, which per se had little or no effect in both the models of nociception. Further, the per se analgesic effect of acetylcholine and neostigmine was blocked by both L-NAME and methylene blue in the models of nociception, suggesting the activation of NO-cGMP pathway. Also, both L-NAME and methylene blue blocked the per se analgesic effect of sildenafil. These results indicate the peripheral accumulation of cGMP may be responsible for antinociceptive effect, and a possible interaction between cholinergic agents and PDE5 system in models of nociception.