Minesh Khashu

Perinatal Outcomes Associated With Preterm Birth at 33 to 36 Weeks’ Gestation: A Population-Based Cohort Study

OBJECTIVE. The aim of our population-based study was to compare the mortality and morbidity of late-preterm infants to those born at term. Advancement in the care of extremely preterm infants has led to a shift of focus away from the more mature preterms, who are being managed as “near terms” and treated as “near normal.” Some recent studies have suggested an increased risk of mortality and morbidity in this group compared with infants born at term. However, there are few population-based mortality and morbidity statistics for this cohort, particularly reflecting current practice. METHODS. Using data from the British Columbia Perinatal Database Registry we analyzed all singleton births between 33 and 40 weeks’ gestation from April 1999 to March 2002 in the province of British Columbia, Canada. We divided this birth cohort into late preterm (33–36 weeks, n = 6381) and term (37–40 weeks, n = 88 867) groups. We compared mortality and morbidity data and associated maternal factors between the 2 groups. RESULTS. Stillbirth rate and perinatal, neonatal, and infant mortality rates were significantly higher in the late-preterm group. Infants in this group needed resuscitation at birth more frequently than those in the term group. Late-preterm infants had a significantly higher incidence of respiratory morbidity and infection and had a significantly longer duration of hospital stay. Maternal factors that were more common in the late-preterm group included chorioamnionitis, hypertension, diabetes, thrombophilia, prelabor rupture of membranes, primigravida, and teenage pregnancy. CONCLUSIONS. Our data support recent literature regarding neonatal mortality and morbidity in late-preterm infants and warrants a review of care for this group at the local, national, and global levels. Reorganization of services and increased resource allocation may be needed in most hospitals and community settings to achieve optimization of care for this group of infants.

Persistent Bacteremia and Severe Thrombocytopenia Caused by Coagulase-Negative Staphylococcus in a Neonatal Intensive Care Unit

OBJECTIVE. Coagulase-negative Staphylococcus (CoNS) is the most frequent cause of late-onset sepsis in NICUs, but mortality is rare and morbidity is unusual. We report a new syndrome of CoNS sepsis characterized by significant morbidity and persistent bacteremia despite aggressive antibiotic therapy and no identified focus of infection. METHODS. We conducted a retrospective review of infants in the NICU with CoNS bacteremia between 2000 and 2002. Statistical analysis included an initial exploratory analysis followed by logistic regression. Microbiological identification of all isolates and molecular typing were performed. RESULTS. Thirty-one neonates with persistent CoNS bacteremia were compared with 60 randomly selected neonates from a group of 140 with nonpersistent CoNS bacteremia. The clinical manifestations at presentation, gestational ages, and birth weights were similar in the 2 groups. Thrombocytopenia was present in 26 (84%) neonates with persistent CoNS bacteremia but only in 8 (13%) neonates in the nonpersistent group. Central venous catheterization increased the risk for persistent CoNS bacteremia, but 42% of the persistent group was never catheterized. Staphylococcus epidermidis was the most common isolate in both groups. Molecular typing failed to identify a predominant clone. CONCLUSIONS. The syndrome of persistent CoNS septicemia is remarkable for thrombocytopenia and persistence in the absence of central venous catheterization. Clinical manifestations at presentation and demographic characteristics did not discriminate between the persistent and nonpersistent groups. We did not identify the emergence of a particularly virulent clone, but it is possible that some strains of CoNS have acquired the capacity to persist under different conditions.

Impact of shielding parenteral nutrition from light on routine monitoring of blood glucose and triglyceride levels in preterm neonates

Background: Premature infants are vulnerable to complications related to oxidative stress. Exposure to light increases oxidation products in solutions of total parenteral nutrition (TPN) such as lipid peroxides and hydrogen peroxide. Oxidative stress impairs glucose uptake and affects lipid metabolism. Hypothesis: products of photo-oxidation contaminating TPN affect lipid metabolism. Objective: Evaluate the effect of photoprotection of TPN in preterm infants on plasma glucose and triglyceride (TG) concentrations. Design: Secondary analysis of a prospective study allocating preterm infants to light-exposed (LE, n = 32) or light-protected (LP, n = 27) TPN. Setting: Level III NICU referral centre for patients of British Columbia. Patients: Preterm infants requiring TPN. Interventions and outcome measures: TG and blood glucose measured during routine monitoring while on full TPN were compared between LE and LP. Results: Clinical characteristics were similar between the two groups (gestational age 28±1 wk; birth weight: 1.0±0.1 kg). Nutrient intakes from TPN and from minimal enteral nutrition were comparable between LE and LP. Blood glucose was higher in preterm infants receiving LE (p<0.001). The accumulation of TG with increasing lipid intake was twice as high with LE accounting for significantly higher TG levels on days 8 and 9 (p<0.05). Conclusions: Failure to photoprotect TPN may cause alterations in intermediary metabolism. Shielding TPN from light provides a potential benefit for preterm infants by avoiding hypertriglyceridaemia allowing for increased substrate delivery.

Congenital mesoblastic nephroma presenting with neonatal hypertension.

Congenital mesoblastic nephroma (CMN) is a rare tumor with an estimated incidence of about 8/million in children under 15 years of life. It is, however, the most common renal tumor in neonates, with more than 80% of CMN tumors presenting in the neonatal period. In 1967, Bolande et al. described CMN as a separate entity from congenital Wilms’ tumor and it is now considered a generally benign renal tumor (as opposed to its variant, the atypical mesoblastic nephroma; AMN). Nephrectomy alone is the treatment of choice with a reported survival of over 98%. Hypertension has been reported with many renal tumors, with or without hyper-reninemia. To date, only nine patients with CMN and hypertension have been reported, out of which six were neonates. We describe the clinical presentation and discuss the findings on abdominal imaging in a 30-week gestation infant with hypertension and CMN.

Early life events, sex, and arterial blood pressure in critically ill infants.

Objective: To determine whether photo-protecting total parenteral nutrition in preterm infants influences arterial blood pressure differently according to gender. Blood pressure is influenced by complex mechanisms of vasomodulation. Oxidants are mediators and effectors in such reactions. Shielding total parenteral nutrition from light contributes to decrease the generation of peroxides. Girls may be better protected against an oxidant load than boys. We questioned whether shielding total parenteral nutrition may have cardiovascular effects that are influenced by gender. Design: A post hoc subgroup analysis of the effect of shielding parenteral nutrition from light. Setting: Neonatal intensive care unit. Subjects: Preterm infants <1000 g with indwelling arterial catheters who received light exposed (n = 20) or light protected (n = 20) parenteral nutrition. Interventions: Invasive monitoring, total parenteral nutrition. Measurements and Main Results: Arterial blood pressure was recorded hourly and compared between light exposed and light protected over the first week of life; timed average maximum velocity (m/s) was measured in the superior mesenteric artery by Doppler; presence of ductus arteriosus was documented by cardiac ultrasound. Data were analyzed by analysis of variance. No differences were noted between light exposed and light protected in clinical determinants that may influence blood pressure. There was an interaction (p < .01) between gender and total parenteral nutrition on blood pressure. In girls (n = 17), systolic and diastolic blood pressures were higher (p < .01) and heart rate lower (p < .01) during light exposed. There was no effect on BP observed in boys (n = 23). The linear correlation between timed average maximum velocity and systolic blood pressure was positive (p < .05). There was no echocardographic difference in hemodynamic variables between boys (n = 21) and girls (n = 9) who had a patent ductus. Conclusion: Failure to shield total parenteral nutrition from light results in higher blood pressure in a selected population of critically ill female infants. This information adds to our understanding of the multiple determinants involved in optimizing arterial blood pressure in a critical care environment.

Vitamin A Is Systemically Bioavailable After Intratracheal Administration With Surfactant in an Animal Model of Newborn Respiratory Distress

Chronic lung disease (CLD) is a major cause of long-term morbidity in extremely LBW infants with respiratory distress syndrome. Parenteral vitamin A administration decreases the risk of CLD. We tested the hypothesis that intratracheal vitamin A administration with surfactant is systemically bioavailable without interfering with the functional properties of exogenous surfactant. Newborn piglets were ventilated with 100% FiO2 and sequential saline lavage induced respiratory distress syndrome. During lung injury induction, ventilator changes were allowed, but none were made following treatment allocation. Animals were assigned by chance in a blinded control trial to three groups: I = control; II = surfactant; III = surfactant + vitamin A. Hemodynamics, lung mechanics, and blood gases were measured following instrumentation, pre- and posttreatment for 4 h, at which time the liver was sampled for retinol determination. All parameters improved in animals receiving surfactant. A significant interaction existed between time and group for PaO2 and alveolar-arterial oxygen difference (A-aDO2). Hepatic levels of retinol were higher (p < 0.001) in animals receiving retinyl acetate. Intratracheal administration of surfactant + vitamin A did not alter the beneficial effects of surfactant on lung compliance and gas exchange. Intratracheal Vitamin A was associated with rapid hepatic uptake. Further studies are warranted.

Variations in metabolic response to TPN are influenced more by sex than by light exposure.

Background: Failure to protect total parenteral nutrition (TPN) solutions from ambient light induces the generation of peroxides, which contributes to the oxidation of several amino acids. We hypothesized that photo-protection improves the metabolic response to TPN. Aim: To study the effects of photo-protecting TPN on urinary nitrogen and vitamin C excretion and to evaluate in premature infants the influence of sex. Patients and Methods: Premature infants were randomized to receive from birth light-exposed (LE) or light-protected (LP) TPN. Upon reaching full TPN, parenteral nutrient intakes were correlated with normalized urinary nitrogen and vitamin C concentrations. Results: No differences were observed between LE and LP. However, sex-related differences were observed in nitrogen and vitamin C handling. In boys, 50% of the nitrogen loss was explained by parenteral amino acid intake, whereas in girls, no correlation was found. The inverse correlation observed between intake and urinary excretion only in girls suggests a state of greater vitamin C utilization in girls. Conclusions: These results demonstrate that sex-related differences in nitrogen/protein metabolism reported during enteral nutrition are seen during TPN as well. Sex is an important variable that will need to be taken into account in future studies evaluating the potential clinical effects of photo-protecting TPN.

Gastric pneumatosis in a preterm infant

1808 www.thelancet.com Vol 366 November 19, 2005 A baby boy at 32 weeks’ gestation was born by spontaneous onset of preterm labour. He weighed 2265 g and had Apgar scores of 7 at 1 min and 9 at 5 min. He was clinically stable for 3 days and was started on enteral feeds. On the fourth day, we noted that he had temperature instability and abdominal distension with sanguineous gastric aspirates. He had poor perfusion, lactic acidaemia, and hyperglycaemia, and needed intubation and fluid resuscitation. Abdominal radiographs showed gastric and intestinal pneumatosis without any evidence of free intraperitoneal or portal venous air (figure). Leucopenia, neutropenia, and thrombocytopenia were also present, and we started the boy on antibiotics after blood culture. Because no organism was isolated, we did not do a laparotomy. He improved over the next month but became intolerant to the enteral feeds. We did a contrast study, which showed small bowel obstruction. At laparotomy we found several old small bowel perforations with associated strictures, and resected two small ileal segments. His stomach and duodenum did not show any abnormality. Histopathology was consistent with necrotising enterocolitis with perforation, and a rectal biopsy showed submucosal ganglia with normal cholinesterase pattern. Although necrotising enterocolitis is common in babies in neonatal intensive care, gastric pneumatosis is rare and usually follows cardiac surgery, pyloric or duodenal stenosis, or intramural misplacement of a feeding catheter. Gastric pneumatosis in a preterm infant

The Tale of a Belly Button: Rieger Syndrome

A male infant was born at 32 weeks’ gestation to a 19-year-old Caucasian mother by vaginal delivery following induction for worsening gestational hypertension. The mother has a history of insulin-dependent diabetes mellitus since 2 years of age. She also gave a history of hypodontia and an umbilical abnormality that needed surgical inter vention. Findings from antenatal serology and scans at 6 and 21 weeks gestation were reported normal. The mother received 2 doses of antenatal corticosteroids in view of prematurity, and intrapartum antibiotics for a positive Group B Streptococcal status. The infant was suppressed at birth and required intubation for poor respiratory effort. Apgars were 2 and 7 at 1 and 5 minutes, respectively. Birth weight was 1,615 kg (10%), length 40 cm (25%), and head circumference 29 cm (25%). The infant was noted to have a broad nasal bridge, flat philtrum with a very thin upper lip, down-turned corners of the mouth, and a deep crease below his lower lip. The umbilical cord was covered with skin; the cranial umbilical skin length was 40 mm and the caudal was 25 mm (Figure 1). The infant required ventilation for 24 hours and continuous positive airway pressure for 72 hours for respiratory distress syndrome and received systemic antibiotics for 5 days. He required phototherapy for unconjugated hyperbilirubinemia from days 4 to 8. Subsequent course in the nursery was uneventful. In view of the umbilical skin abnormality and minor facial dysmorphism the possibility of Rieger syndrome was considered. Ophthalmic examination revealed posterior embryotoxon without any other manifestations of goniodysgenesis. He did not have evidence of glaucoma at this stage. In addition to maternal history of an abnormal umbilicus and hypodontia, there was family history of hypodontia, glaucoma, and umbilical abnormalities requiring surgery.