Changing parenteral nutrition administration sets every 24 h versus every 48 h in newborn infants.

OBJECTIVE: To determine whether changing total parenteral nutrition fluid administration sets (TAS) every 48 h rather than every 24 h results in a greater infusate contamination rate. PATIENTS AND METHODS: Prospectively, 166 infants were assigned at random to have TAS changed either every 24 h or every 48 h. Samples of the infusate were cultured to determine contamination rates of the infusate in the sets and were tested from 149 of these infants. TAS was replaced every 24 h in the control group, and 445 amino acid plus dextrose solutions (AADS) and 449 lipid emulsions samples were taken for bacterial culture. Fungal cultures were also performed on 449 samples. The study group had TAS replaced every 48 h, and 454 samples of AADS were cultured for bacteria. The numbers of lipid emulsion samples sent for bacterial culture and fungal culture were 449 and 440, respectively. Information on type of intravenous access device, administration of antibiotics and blood cultures was also collected. RESULTS: There was no difference in bacterial contamination rates for AADS or lipid emulsion from TAS changed every 24 or 48 h (c2, P>0.05). Lipid emulsion sampled from the 24 h group showed a statistically significant higher rate of fungal contamination than specimens from the 48 h group (P<0.01). CONCLUSIONS: Changing TAS every 48 h versus 24 h does not increase the contamination rate of infusate in newborns.

Randomized, controlled, blinded trial of doxapram for extubation of the very low birthweight infant.

The objective of the study was to determine whether administering doxapram by infusion to the very low birthweight infant, prior to extubation during the first 3 weeks of life, would increase the incidence of successful extubation. The study patients, 56 infants of less than 1251 g birthweight and less than 30 weeks' gestation, were entered in the first 3 weeks of life when lung disease had started to improve. A randomized blinded trial was performed, with infants receiving 3.5 mg kg(-1) doxapram bolus, followed by an infusion at 1 mg kg(-1) h(-1), or placebo. Weaning from positive pressure ventilation was standardized and extubation occurred after a 12 h trial of an intermittent mandatory ventilation (IMV) rate of 6 breaths min(-1), if PCO2 < 55 mmHg, pH > 7.26, and FiO2 < 0.45. Study drug was continued for 48 h postextubation, and the infants were placed on nasopharyngeal continuous positive airway pressure (CPAP) for 72 h postextubation. Extubation failure within the first 72 h after extubation was objectively defined in terms of acidosis (pH < 7.26), hypercarbia (PCO2 > 55 mmHg), excessive oxygen requirement (FiO2 > 0.8) or frequent apnoea (more than three in 12 h, or more than two requiring face mask IMV in 24 h). No difference was noted in the frequency of successful extubation between the groups. Fifteen infants in each group were successfully extubated before the 10th day of the study. In conclusion, when given in accordance with this protocol doxapram does not increase the likelihood of successful extubation in the very low birthweight infant. Increasing successful extubations in this group of infants will require other strategies.

Comparison of ring block, dorsal penile nerve block, and topical anesthesia for neonatal circumcision: a randomized controlled trial.

CONTEXT: Beliefs about the safety and effectiveness of current anesthetics have resulted in many newborns being circumcised without the benefit of anesthesia. OBJECTIVE: To compare ring block, dorsal penile nerve block, a topical eutectic mixture of local anesthetics (EMLA), and topical placebo when used for neonatal circumcision. The placebo represented current practice, with no anesthetic for neonatal circumcision. DESIGN: A randomized controlled trial. SETTING: Antenatal units in 2 tertiary care hospitals in Edmonton, Alberta. PARTICIPANTS: A consecutive sample of 52 healthy, full-term, male newborns, aged 1 to 3 days. INTERVENTIONS: Physiological and behavioral monitoring occurred in a series of trials: baseline, drug application, preparation, circumcision, and postcircumcision. Surgical procedures defined the following 4 stages of the circumcision: cleansing, separation, clamp on, and clamp off. Methemoglobin level was assessed 6 hours after surgery. MAIN OUTCOME MEASURES: Heart rate, cry, and methemoglobin level. RESULTS: Newborns in the untreated placebo group exhibited homogeneous responses that consisted of sustained elevation of heart rate and high-pitched cry throughout the circumcision and following. Two newborns in the placebo group became ill following circumcision (choking and apnea). The 3 treatment groups all had significantly less crying and lower heart rates during and following circumcision compared with the untreated group. The ring block was equally effective through all stages of the circumcision, whereas the dorsal penile nerve block and EMLA were not effective during foreskin separation and incision. Methemoglobin levels were highest in the EMLA group, although no newborn required treatment. CONCLUSIONS: The most effective anesthetic is the ring block; EMLA is the least effective. It is our recommendation that an anesthetic should be administered to newborns prior to undergoing circumcision.

A case of aplasia cutis congenita in dizygotic twins.

We report a newborn infant with extensive aplasia cutis congenita of the flanks and thighs, associated with a co-twin fetus papyraceus. DNA restriction fragment polymorphism analysis of the twins proved dizygosity. The association of these two conditions in twins is reviewed.

Serial visual evoked potentials and outcome in term birth asphyxia.

Birth asphyxia is a major cause of neonatal mortality and morbidity. It remains difficult to predict accurately neurologic outcome among survivors, particularly infants with moderate hypoxic-ischemic encephalopathy. Visual evoked potential (VEP) is a reproducible measure of cortical function and reflects acute changes in central nervous system status secondary to asphyxial insult. We performed serial VEPs on 36 term infants with documented birth asphyxia to investigate the relationship between VEPs and neurodevelopmental outcome at 18 months of age. Fourteen infants were neurologically intact at subsequent examination; all had normal VEPs during the first week of life. Twenty-two infants had died or were significantly handicapped at 18 months of age; 20 had abnormal VEPs persisting beyond day 7 of life. Abnormal VEPs accurately predicted abnormal outcome (100%) and were both sensitive (91%) and specific (100%). In 20 infants who were classified as moderately asphyxiated according to the criteria of Sarnat and Sarnat, even greater accuracy, sensitivity, and specificity (all 100%) were observed. VEPs demonstrate good correlation with neurodevelopmental outcome in term infants with birth asphyxia and provide accurate prognostic information useful in the clinical management of these infants.

Neonatal apnea: diagnosis by nurse versus computer.

In an effort to characterize significant neonatal apnea and evaluate the nursing diagnosis of apnea, apnea type and frequency were determined in 27 infants by continuous computer recording of heart rate, respiratory impedance, end-tidal CO2, and either or both transcutaneous oxygen and pulse oximetry. Of the 1,266 recorded apneas, 46% were central, 44% were mixed, and 10% were obstructive. Mixed apnea was associated with a longer mean duration and greater mean decrease in heart rate than central apnea. Apnea duration was positively correlated with both a decrease in heart rate and oxygen saturation (P less than .001), and a lower baseline saturation was associated with a greater decrease in oxygen saturation during apnea (P = .002). Theophylline therapy had no effect on apnea duration or oxygen desaturation but resulted in a decrease in the mean heart rate decrease associated with apnea. Overall, nurses diagnosed 54% of all apneic episodes and were significantly poorer at detecting mixed and obstructive events. Nursing detection of apnea improved with increasing apnea duration and was always associated with a greater decrease in heart rate. Nurses diagnosed significantly fewer mixed apnea following theophylline therapy. Improved monitoring techniques, particularly for mixed and obstructive apnea, are essential to increase apnea detection in the nursery.

The dose response of theophylline in the treatment of apnea of prematurity.

In an effort to establish the minimum effective dose of theophylline in the treatment of idiopathic apnea of prematurity, a prospective trial of 22 infants with at least 0.33 episodes of apnea per hour were studied. Apnea was diagnosed exclusively by continuous recording of heart rate, respiratory impedance, end-tidal CO2, and either or both transcutaneous oxygen and pulse oximetry. Four discrete serum concentrations of theophylline (23 mumol/l or 4.2 mg/L, 47 mumol/L or 8.5 mg/L, 70 mumol/L or 12.7 mg/L, and 84 mumol/L or 15.3 mg/L) were attained by using repeated loading doses of 4 mg/kg and increasing the maintenance dose from 1 to 1.5 mg/kg to 2 to 2.5 mg/kg, given every 8 hours. Before treatment and 24 hours after each loading dose, airway occlusions and measures of tidal volume, minute ventilation, and respiratory timing were performed. The effectiveness of therapy was assessed by either a continuous computer data-acquisition system or paper recording for the duration of the study. Of the 22 infants, three responded at level 1, three at level 2, and 10 at level 3. One of the four infants loaded to the fourth level had a sustained response for a total cumulative response of 77%. The five remaining infants required additional treatment with doxapram or continuous positive airway pressure. There was a significant increase in inspiratory pressure 100 msec after airway occlusion, maximum inspiratory pressure during airway occlusion, tidal volume, ratio of tidal volume to inspiratory time (mean inspiratory flow), and minute ventilation from the pretreatment measurements to those at the maximum dose of theophylline. The apnea response did not correlate with these improvements in ventilation measures.