Dopamine versus dobutamine in very low birthweight infants: endocrine effects.

OBJECTIVES: To compare the endocrine effects of dopamine and dobutamine in hypotensive very low birthweight (VLBW) infants. DESIGN: Non-blinded randomised prospective trial. SETTING: Level III neonatal intensive care unit. PATIENTS: 35 hypotensive VLBW infants who did not respond to volume loading, assigned to receive dopamine or dobutamine. MEASUREMENTS: Haemodynamic variables and serum levels of thyroid stimulating hormone (TSH), total thyroxine (T(4)), prolactin (PRL) and growth hormone were assessed during the first 72 h of treatment and the first 72 h after stopping treatment. RESULTS: Demographic and clinical data did not significantly differ between the two groups. Necessary cumulative and mean drug doses and maximum infusion required to normalise blood pressure were significantly higher in the dobutamine than in the dopamine group (p<0.01). Suppression of TSH, T(4) and PRL was observed in dopamine-treated newborns from 12 h of treatment onwards, whereas levels of growth hormone reduced significantly only at 12 h and 36 h of treatment (p<0.01). TSH, T(4) and PRL rebound was observed from the first day onwards after stopping dopamine. Dobutamine administration did not alter the profile of any of the hormones and no rebound was observed after stopping treatment. CONCLUSION: Dopamine and dobutamine both increase the systemic blood pressure, though dopamine is more effective. Dopamine reduces serum levels of TSH, T(4) and PRL in VLBW infants but such suppression is quickly reversed after treatment is stopped. Further research is required to assess if short-term iatrogenic pituitary suppression has longer-term consequences.

Central venous catheters and cardiac tamponade in preterm infants.

OBJECTIVE: To determine the incidence of cardiac tamponade related to peripherally inserted central catheters in newborns weighing less than 1,500 g during the past 8 years and to provide guidelines in order to avoid death due to this complication. DESIGN: Retrospective case review. SETTING: Tertiary level neonatal intensive care unit. PATIENTS AND PARTICIPANTS: Retrospective study of a total of 280 peripherally inserted central catheters positioned in 258 preterm newborns. MEASUREMENTS AND RESULTS: Five cardiac tamponades were observed, giving an incidence of 1.8%. Data from our cases included clinical presentation and outcome, biochemical evaluation of pericardial fluid, days until diagnosis, central catheters characteristics, insertion site and tip placement site. INTERVENTION: Two of the infants did not respond to resuscitation measures including cardiac massage and the administration of epinephrine. Post-mortem examination revealed the intrapericardial accumulation of protein and lipid alimentation solution. The other three patients were successfully resuscitated by timely pericardiocentesis. All five infants had routinely performed serial radiographs and cardiac color Doppler ultrasonography that showed correct catheter tip placement. CONCLUSIONS: The incidence of cardiac tamponade could be reduced by following specific guidelines. The possibility of tamponade must be kept in mind during the resuscitation of any preterm infant with a peripherally inserted central catheter in place who develops symptoms of shock or sudden bradycardia. Our experience shows that even preterm infants with cardiac tamponade can be successfully resuscitated by timely pericardiocentesis in most cases.

Diagnosis of gastro-oesophageal reflux in preterm infants: sonography vs. pH-monitoring.

OBJECTIVES: To compare the ultrasound examination with pH-metry in order to evaluate the diagnostic accuracy of sonography for diagnosis of gastro-oesophageal reflux (GOR) in preterm infants. METHODS: A prospective study was conducted on 31 premature infants <34 weeks with clinically diagnosed GOR. First, they underwent 24-hour pH-monitoring; successively, the sonographic assessment was performed within 12 h after pH-monitoring. The two operators who performed the pH-monitoring and sonography respectively, were unaware of each other's results. RESULTS: Twenty-one patients (67.7%) had significant GOR with a reflux index >5 (GOR group). The median (range) reflux index in this group was 9.19% (6.04-20.1). Ten newborns (32.3%) did not have significant GOR with a reflux index <5. Sonography was positive for GOR in 8 patients (25.8%); all 8 infants with sonographic diagnosis of GOR had a reflux index >5. Therefore, sonographic diagnosis did not produce false positives. Sonography was negative in 23 newborns (74.2%); 13 of these were positive to pH-monitoring and may therefore be considered as false negatives. Respect to continuous 24-hour pH-monitoring, sonography showed a specificity of 100% but a very low sensitivity of 38% with a positive prediction value of 100% and a negative prediction value of 43%. CONCLUSIONS: Sonography should not replace 24-hour pH monitoring for detecting GOR in preterm infants. However, sonography has a very high specificity and a positive predictive value of 100%. When clinicians suspect GOR in preterm infants, it could be useful for selection of cases to refer for pH-metry.

Umbilical cord care in premature infants: the effect of two different cord-care regimens (salicylic sugar powder vs chlorhexidine) on cord separation time and other outcomes.

OBJECTIVES: To evaluate the effect of 2 cord-care regimens (salicylic sugar powder vs chlorhexidine as a 4% detergent water solution) on cord separation time and other outcomes in preterm infants. METHODS: A prospective, randomized, controlled trial was conducted on 244 preterm newborns with a gestational age of <34 weeks and a birth weight of <2500 g. All preterm newborns were enrolled, regardless of their health condition. We excluded from the study infants whose conditions during the first hours of life required the catheterization of umbilical vessels. We also excluded from the general statistical analysis all newborns who had their programmed cord-care regimen changed because of the presence or the suspicion of omphalitis. On arrival at our neonatal intensive care unit or neonatal special care unit, infants were bathed thoroughly with a soap solution (Saugella, Guieu, Italy), and the umbilical cord (UC) was treated with 1 of the 2 antiseptic products chosen for the study. The stump was then folded and covered with common sterile, dry gauze and kept in place by an elastic net. Until cord detachment and at every diaper change, the cord stump was cleaned with sterile water and treated with the same product initially used for first-time cord care. On the third day of life, we obtained an umbilical swab either from the base of the cord or from the umbilicus if the cord was already sloughed. Six weeks after birth, during hospitalization or during a follow-up visit if already discharged, all infants had a medical examination to check the umbilicus area. Cord separation time, changing of the programmed cord-care regimen, death, omphalitis, sepsis, cord bleeding, nurses' opinion on treatments efficacy, and UC colonization were measured. RESULTS: The cord separation time was significantly lower in infants who were treated with salicylic sugar powder (6 +/- 2 days) than in infants who were treated with chlorhexidine (9 +/- 2 days). The programmed cord-care regimen was changed in a significantly higher number of newborns in the chlorhexidine group (17) than in the salicylic sugar group (3). None of the newborns died, and we found only sporadic cases of sepsis (1 patient in each group) and omphalitis (1 patient in the chlorhexidine group). A significantly higher percentage of nurses were satisfied with the salicylic sugar powder treatment (98%) than with the chlorhexidine treatment (67%), notwithstanding a more frequent occurrence of slight cord scar bleeding in the salicylic sugar group (7.8%) than in the chlorhexidine group (4%). The rate of negative umbilical swabs was significantly higher in infants treated with salicylic sugar powder (73.1%) than with chlorhexidine (53%). CONCLUSIONS: In neonatal intensive care units and neonatal special care units of developed countries, salicylic sugar powder can be used effectively and safely for UC care of preterm infants.