Houchang D. Modanlou

Multicenter controlled trial comparing high-frequency jet ventilation and conventional mechanical ventilation in newborn infants with pulmonary interstitial emphysema

One hundred forty-four newborn infants with pulmonary interstitial emphysema were stratified by weight and severity of illness, and randomly assigned to receive treatment with high-frequency jet ventilation (HFJV) or rapid-rate conventional mechanical ventilation (CV) with short inspiratory time. If criteria for treatment failure were met, crossover to the alternate ventilatory mode was permitted. Overall, 45 (61%) of 74 infants met treatment success criteria with HFJV compared with 26 (37%) of 70 treated with CV (p less than 0.01). Eighty-four percent of patients who crossed over from CV to HFJV initially responded to the new treatment, and 45% ultimately met success criteria on HFJV. In contrast, only 9% of those who crossed over from HFJV to CV responded well to CV (p less than 0.01), and the same 9% ultimately met success criteria (p less than 0.05). Therapy with HFJV resulted in improved ventilation at lower peak and mean airway pressures, as well as more rapid radiographic improvement of pulmonary interstitial emphysema, in comparison with rapid-rate CV. Survival by original assignment was identical. When survival resulting from rescue by the alternate therapy in crossover patients was excluded, the survival rate was 64.9% for HFJV, compared with 47.1% for CV (p less than 0.05). The incidence of chronic lung disease, intraventricular hemorrhage, patent ductus arteriosus, airway obstruction, and new air leak was similar in both groups. We conclude that HFJV, as used in this study, is safe and is more effective than rapid-rate CV in the treatment of newborn infants with pulmonary interstitial emphysema.

Sinusoidal fetal heart rate pattern: Its definition and clinical significance

A review was made of the available literature on the sinusoidal heart rate (SHR) pattern. A specific definition of SHR was made in order to elucidate its clinical significance. According to this definition 41 tracings from 23 publications were classified as being either true SHR, equivocal, or a heart rate pattern other than SHR. On the basis of this definition, 27 tracings were classified as true SHR patterns and all were associated with significant fetal or neonatal morbidity or mortality, except in two cases after administration of alphaprodine. Three tracings were judged to be equivocal. In two other cases the fetal heart rate tracings were classified as nonsinusoidal premortem patterns associated with poor perinatal outcome. As for the other nine tracings that did not meet the proposed definition, the perinatal outcome was normal. Therefore, because of a stricter definition of jeopardy, except when the SHR pattern appears after induction of analgesia with alphaprodine.

Percutaneously Inserted Central Catheter for Total Parenteral Nutrition in Neonates: Complications Rates Related to Upper Versus Lower Extremity Insertion

OBJECTIVE. The objective of this study was to compare the complication rates of upper versus lower extremity percutaneously inserted central catheters used for total parenteral nutrition in neonates. METHODS. During a 48-month study period, 396 neonates were identified as having had percutaneously inserted central venous catheters. A total of 370 catheters were inserted from the upper and 107 from the lower extremity. Data retrieved and analyzed were birth weight, gestational age, age at placement, duration in place, duration of total parenteral nutrition, type of infusates, catheter-related bloodstream infection, phlebitis, leakage, occlusion, necrotizing enterocolitis, intraventricular hemorrhage, serum creatinine, liver function tests, and length of hospitalization. RESULTS. The median birth weight and gestational age were 940 g and 28 weeks. The rate of catheter-related bloodstream infection was 11.6% for the upper and 9.3% in the lower extremity catheters. The most common organism was coagulase-negative Staphylococcus for both upper and lower extremity catheters and significantly higher with catheters from the upper extremity. Lower extremity catheters were in place longer, and the time from insertion to complication was also longer. The rate of cholestasis was higher for the upper extremity catheters. Multiple regression analysis showed that the most significant contributor to cholestasis was duration of time the catheters were in place and the duration of total parenteral nutrition administration. Receiver operating characteristics curve demonstrated higher sensitivity for duration of catheters in predicting cholestasis with duration of total parenteral nutrition being more specific. CONCLUSION. Lower extremity percutaneously inserted central venous catheters had lower rates of catheter-related bloodstream infection, longer time to first complication, and lower cholestasis despite longer duration of total parenteral nutrition. When possible, lower extremity inserted catheters should be used for the administration of total parenteral nutrition.

Prophylactic or Simultaneous Administration of Recombinant Human Granulocyte Colony Stimulating Factor in the Treatment of Group B Streptococcal Sepsis in Neonatal Rats

ABSTRACT: Despite the emergence of newer antibiotic treatments, group B streptococcal infection still carries a high mortality rate in the newborn and is characterized by reduced neutrophil proliferative pools, neutrophil storage pools, neutropenia, and polymorphonuclear cell dysfunction. Recombinant human granulocyte-colony stimulating factor (rhG-CSF) has recently been demonstrated to induce neutrophilia and modulate neutrophil proliferative pools and neutrophil storage pools in the newborn rat. We therefore investigated the adjuvant effect of rhG-CSF given to group B streptococcus (GBS) septic Sprague-Dawley newborn (<36 h) rats treated with and without antibiotic therapy. After inoculation of GBS, a GBS survival curve established the LD50 at 50 h to be approximately 3 X 10* organisms/gm. Newborn rats were divided into four treatment groups after GBS inoculation. rhG-CSF was administered at the same time as GBS inoculation. At 24 h, there was approximately 100% survival in all groups. However, by 72 h after GBS inoculation, there was a significant difference in survival. Group 1, PBS/Alb, had a survival rate of 4%; group 2, rhG-CSF, 9%; group 3, antibiotics, 28%; and group 4, antibiotics plus rhG-CSF, 91% (p<0.001). Additionally, when rhG-CSF was administered prophylactically (6 h before GBS), a similar significant synergistic effect in survival was demonstrated with granulocyte colony stimulating factor plus antibiotics versus antibiotics alone (70 versus 10%) (p<0.01). These preliminary data suggest that either simultaneous or prophylactic pulse administration of rhG-CSF may have a synergistic and protective effect on survival in antibiotic-treated experimental GBS in the neonatal rat.

Growth, biochemical status, and mineral metabolism in very-low-birth-weight infants receiving fortified preterm human milk.

We compared the growth, biochemical status, and mineral status of 30 very-low-birth-weight infants randomly assigned to receive preterm human milk (Group I, 10 infants) from their own mothers, fortified preterm human milk (Group II, 8 infants), or a high-caloric-density premature formula (Group III, 12 infants). Added to the infants own mothers milk, a human milk fortifier at full strength provided additional protein (60:40 whey/casein, 0.7 g/dl), calories (4 kcal/oz), and minerals. Volume of intake, feeding tolerance, and complications were similar in the three groups. Infants receiving fortified preterm human milk showed growth, biochemical status, and mineral status similar to those receiving high-caloric-density formula, but infants receiving fortified preterm human milk grew faster (12.0 +/- 3.2 vs. 8.9 +/- 1.1 days/300 g, p less than 0.05), had higher serum protein (4.6 +/- 0.5 vs. 4.2 +/- 0.2 g/dl, p less than 0.05), and tended to have better mineral status (higher serum calcium, lower alkaline phosphatase, and higher serum phosphorus, none individually significant) than infants receiving preterm human milk alone. This study supports previous observations that fortified preterm human milk provides nutritional advantages for very-low-birth-weight infants.

Thrombocytopenia in Neonatal Infection

Serial platelet counts by phase microscopy were done for three groups of neonates who were admitted to the Special Care Unit of the Miller Childrens Hospital. Group 1 (78 neonates) was evaluated for septicemia. Group 2 (28 neo nates) was randomly selected sick neonates whose working diagnosis was not septicemia. Group 3 (16 neonates) was clinically normal preterm neonates (28 to 36 weeks gestation). For groups 1 and 2, platelet counts were done serially, at the time blood and cerebrospinal fluid cultures were obtained and then 12, 24, 48 and 72 hours later. For group 3, platelet counts were done on the second, seventh, fourteenth, twenty-first, and twenty-eighth day of life. Sixteen of the group 1 infants were found to have septicemia; ten of these 16 had thrombo cytopenia (platelets <100,000/mm3). In group 2, five infants had thrombocyto penia, one because of isoimmune disease and four as a result of possible disseminated intravascular coagulation. Thrombocytopenia persisted for 1 to 10 days; platelet counts of group 3 were the same as those of older children and adults.

Effects of Brief, Clustered Versus Dispersed Hypoxic Episodes on Systemic and Ocular Growth Factors in a Rat Model of Oxygen-Induced Retinopathy

Oxygen fluctuation patterns in preterm infants who develop retinopathy of prematurity (ROP) are varied and poorly represented in animal models. We examined the hypothesis that clustered (CL) episodes of hypoxia during hyperoxia results in a more severe form of oxygen-induced retinopathy (OIR) than dispersed episodes. Rat pups were exposed to alternating cycles of 1) 50% O2 with three CL episodes of 12% O2 every 6 h; or 2) 50% O2 with one episode of 12% O2 every 2 h, for 7 (P7) or 14 (P14) days postnatal age. Pups were killed after hyperoxia, or placed in room air (RA) until P21. RA littermates were killed at P7, P14, and P21. Systemic and ocular vascular endothelial growth factor (VEGF), soluble VEGFR-1 (sVEGFR-1), insulin-like growth factor I (IGF-I), and growth hormone were examined. All hyperoxia-exposed retinas had evidence of neovascularization. Animals in the CL group had a more severe form of OIR at P21 evidenced by vascular tufts, leaky vessels, retinal hemorrhage, and vascular overgrowth. These characteristics were associated with low body weight; high systemic and ocular VEGF; and low systemic and high ocular sVEGFR-1 and IGF-I. These data suggest that preterm infants who experience CL fluctuations in Pao2 during supplemental O2 therapy are at a higher risk for severe ROP.

Mean airway pressure—significance during mechanical ventilation in neonates

Variations in PEEP with concomitant changes of DPP while MAP, PIP, flow, FIO2, and ventilator rate remained constant were investigated in nine neonates with RDS during the first and second days of life. After stabilization on baseline ventilator settings, PEEP was increased by 3 cm of H2O and DPP decreased in order to maintain balance MAP. Following a return to baseline settings, the PEEP was decreased by 3 cm of H2O and DPP increased sufficiently to maintain constant MAP. Arterial PaO2, PaCO2, pH, blood pressure, heart rate and a/APO2 ratios were measured before, during, between, and after the experimental conditions. Analysis revealed no significant changes in PaO2, a/APO2, blood pressure, or heart rate during baseline or experimental conditions. PaCO2 decreased significantly when PEEP was decreased and DPP increased, both on day 1 (37.2 +/- 2.4 vs 41.4 +/- 2.3 torr; P less than 0.025) and day 2 (42.1 +/- 2.6 vs 46.8 +/- 2.0 torr; P less than 0.05). Changes in pH were inversely related to PaCO2 changes. This study confirms the importance of MAP in determining oxygenation in newborn infants with RDS. However, ventilation was significantly affected by variation in PEEP and DPP despite a constant MAP.

Sinusoidal heart rate pattern: Reappraisal of its definition and clinical significance

Objectives: To address the clinical significance of sinusoidal heart rate (SHR) pattern and review its occurrence, define its characteristics, and explain its physiopathology.

Perinatal events and intraventricular/subependymal hemorrhage in the very low-birth weight infant

One hundred nineteen very low-birth weight infants were studied to see whether intrapartum fetal distress with or without acidosis correlated with the development of intraventricular and subependymal hemorrhage. Of 112 infants studied prospectively, 24% (27/112) had intraventricular/subependymal hemorrhage documented by real-time ultrasound studies shortly after birth; only 4.4 (5/112) had severe hemorrhage (grade 3/4). Ominous fetal heart rate patterns occurred in 50% of monitored infants with severe intraventricular/subependymal hemorrhage compared to 8% of matched controls (p less than 0.01). Reassuring fetal heart rate patterns were more predominant in infants without intraventricular/subependymal hemorrhage (p less than 0.05). Neonatal depression and the need for assisted ventilation beyond the immediate delivery period were more frequent in infants who developed intraventricular/subependymal hemorrhage. Antepartum and intrapartum complications, fetal presentation, cesarean section, duration of labor, hyaline membrane disease, and volume expansion appeared to play no role in the incidence of intraventricular/subependymal hemorrhage. Preliminary data presented here suggest that intrapartum fetal distress and acidosis may be significant factors in predicting which very low-birth weight infant will develop intraventricular/subependymal hemorrhage. The condition of the infant at birth may be more significant with respect to the extent of intraventricular/subependymal hemorrhage than a variety of obstetric variables. Aggressive management of appropriately selected patients and judicious resuscitation of the very low-birth weight infant may keep the incidence of severe intraventricular/subependymal hemorrhage at a minimum, thereby optimizing neurological outcome for this high-risk group.