Readmission for group B streptococci or Escherichia coli infection among full-term, singleton, vaginally delivered neonates after early discharge from Florida hospitals for births from 1992 through 1994.

BACKGROUND: In Florida during the period 1992 through 1994, there was a major drop in the length of stay for full-term, singleton, vaginally delivered newborn babies in the hospital. A major concern on the part of clinicians has been the potential of an increased risk of sepsis (manifesting itself after discharge) associated with earlier newborn discharge from the hospital. We used the Florida hospital discharge dataset to study the frequency of readmission with sepsis after early newborn discharge to home. METHODS: Using the Florida Agency for Health-Care Administration Acute Care Hospital Discharge Dataset, we used a multivariate, probabilistic matching algorithm to merge newborn discharge records for births from 1992 through 1994 with readmission discharge records (including hospital-to-hospital transfers and multiple readmissions) during the first 28 days of life. We used the resulting merged dataset to study bacterial infection diagnoses on newborn and readmission records and to examine relationships between readmission diagnoses and timing of newborn discharge among the 364,528 full-term, singleton, vaginally delivered babies (FTSVDBs) without congenital anomalies from 1992 through 1994 in Florida acute-care hospitals. RESULTS: Overall, 86.3% of all FTSVDBs born in Florida acute-care hospitals were discharged between day of life (DOL) 0 (born and discharged the same day) and DOL 2 (discharged two calendar days after birth). The group B streptococci (GBS) infection code was found on the newborn discharge records of 9.2 per 10,000 FTSVDBs over the 3-year period, 5.9% of which involved hospital-to-hospital transfer of the baby. Escherichia coli infection codes were found on the records of 3.4 per 10,000 FTSVDBs over the 3-year period, 2.3% of which involved hospital-to-hospital transfer of the baby. Of those FTSVDBs discharged to home without infection codes during DOL 1 to 2, 0.8 per 10,000 were readmitted within 7 days (inclusive) with GBS infection, and 2.0 per 10,000 with E. coli infection. When the data for readmitted babies were pooled for 1992 through 1994, the odds ratio for probability of readmission comparing discharges on DOL 1 to DOL 2 for GBS was 2.27 (95% confidence interval, 1.83 to 2.70), and for E. coli 2.16 (95% confidence interval, 1.46 to 2.85). Over this 3-year period, for babies discharged on DOL 1, there was a 115% increase in the rate of readmission for GBS from 1992 through 1994 (p < 0.01) and a 36.5% increase in the rate of readmission for E. coli (p < 0.05). However, among FTSVDBs discharged on DOL 2, the rate of readmission for both GBS and E. coli did not change during the period 1992 through 1994. There were no deaths among FTSVDBs as either newborns, transfers, or readmissions within 7 days of discharge, with either GBS or E. coli infection codes on their discharge record. CONCLUSION: From 1992 through 1994, the increased number of babies discharged early in Florida was temporally associated with an increased rate of readmission during the week after discharge for both GBS and E. coli infection among babies discharged on the calendar day after birth. With an increase in both the number of babies exposed to the risks of early discharge, and an increased rate of these serious infections during the week after discharge from the hospital, the number of these babies grew to exceed, by several fold, the number of babies with inborn errors of metabolism picked up by state screening programs.

The fatty acid composition of maternal diet affects the response to excitotoxic neural injury in neonatal rat pups.

Fatty acids and their derivatives play a role in the response to neural injury. The effects of prenatal and postnatal dietary fatty acid composition on excitotoxic neural injury were investigated in neonatal rat pups. Dams were fed during gestation and lactation a diet whose fat source was either corn oil or menhaden fish oil. On postnatal day 3, litters were culled to 10 per dam. On postnatal day 4, excitotoxic neural injury was induced by infusion of the glutamate analog N-methyl-DL-aspartate (NMA) into the left cerebral hemisphere. Three days later, pups were killed and brains were removed for histological and volume assessments. Levels of arachidonic acid were 2.3-fold higher in cerebrums of pups in the corn oil group than in the fish oil group. Left cerebral hemispheres among all pups were atrophic. Right cerebral hemispheres of pups in the corn oil group showed more histological evidence of edema, and had significantly higher volumes than pups in the fish oil group (66 vs. 42 mm2, p=0.007). These data suggest that the fatty acid composition of prenatal and/or postnatal diet can affect the neonatal response to excitotoxic neural injury.

Persistent pulmonary hypertension of the neonate and asymmetric growth restriction.

OBJECTIVE: To evaluate the possible associations between persistent pulmonary hypertension of the neonate, need for extra-corporeal membranous oxygenation, small for gestational age (SGA), and low ponderal index for gestational age in infants with persistent pulmonary hypertension of the neonate and in matched controls. METHODS: Eighty-six infants with persistent pulmonary hypertension of the neonate delivered from 1991 to 1994 at our hospital were matched with 430 contemporaneous control singleton neonates. Birth weight and ponderal indices (100 x weight/length3) less than the tenth percentile for gestational age and gender were defined as SGA and low ponderal index, respectively. We assessed associations between these markers, the presence of persistent pulmonary hypertension of the neonate, and the need for extracorporeal membranous oxygenation. RESULTS: Low ponderal index was associated with persistent pulmonary hypertension of the neonate (odds ratio [OR] 5.4), whereas SGA was not. Low ponderal index (OR 4.0) was an independent correlate of persistent pulmonary hypertension of the neonate after adjustment with logistic regression for 5-minute Apgar scores less than 7, umbilical arterial pH less than 7.10, and presence of meconium. Low ponderal index was associated with need for extracorporeal membranous oxygenation in neonates with persistent pulmonary hypertension (P < .001). CONCLUSION: Fetal developmental events may significantly affect neonatal pulmonary status. Diminished neonatal nutritional status, as measured by low ponderal index for gestational age, is associated with increased risk of persistent pulmonary hypertension of the neonate and severity of the disease process.

The fatty acid composition of maternal diet affects lung prostaglandin E2 levels and survival from group B streptococcal sepsis in neonatal rat pups.

Dietary fatty acid effects upon the immune system may be mediated in part by effects upon the synthesis of proinflammatory mediators. The effects of maternal dietary fatty acid composition upon lung prostaglandin (PG) E2 levels and survival from group B streptococcal (GBS) infection were investigated in neonatal rat pups. Beginning on d 2 of gestation and throughout lactation, pregnant dams were fed a purified diet whose fat source (22% of energy) was either corn oil or menhaden fish oil. On postnatal d 3, pups were randomly cross-fostered to dams of the same diet group to minimize litter effects; litters were then culled to 10 pups per dam. On postnatal d 7, pups were either injected with 1 x 10(7.5) GBS organisms or were killed for determination of lung tissue levels of PGE2 and lung and erythrocyte fatty acid composition. Arachidonic acid and PGE2 levels were significantly higher in the lungs of pups in the corn oil group compared with the fish oil group. Forty-nine percent of pups in the corn oil group survived the GBS challenge compared with 79% of pups in the fish oil group (P = 0.0005). These data suggest that the fatty acid composition of pre- and/or postnatal diet affects the neonatal response to immune challenge, which may be due in part to effects upon the synthesis of pro-inflammatory mediators.

Phenoxybenzamine placental transfer during the third trimester.

OBJECTIVE: To report phenoxybenzamine placental transfer in the treatment of maternal hypertension secondary to pheochromocytoma. CASE SUMMARY: A 22-year-old woman diagnosed with pheochromocytoma was medically managed at 33 weeks gestation with oral phenoxybenzamine and labetalol until delivery 26 days later. To determine phenoxybenzamine placental passage, at the time of cesarean section simultaneous samples were obtained from the cord blood, maternal blood, and amniotic fluid. Additional blood samples were obtained from the newborn at 32 and 80 hours of life. Mean concentrations of phenoxybenzamine from cord and maternal plasma and in amniotic fluid were 103.3, 66, and 79.3 ng/mL, respectively; the newborn's plasma concentration at 32 hours of life was 22.3 ng/mL. At the time of delivery, the 2475-g male infant exhibited perinatal depression; mild transient hypotension was also noted for the first few days of life. DISCUSSION: The fetal-maternal plasma accumulation ratio of 1.6:1 indicates that at this gestational age after 26 days of therapy, the placental transfer of phenoxybenzamine occurs and is accompanied by accumulation in the fetal blood. CONCLUSIONS: Because of the placental transfer of phenoxybenzamine, mild perinatal depression and transient hypotension may occur in newborns of mothers receiving this medication. These newborns must be closely monitored during the first few days of life for respiratory depression and hypotension.

Ticarcillin-clavulanic acid pharmacokinetics in preterm neonates with presumed sepsis.

The objective of the reported study was to characterize the pharmacokinetics of ticarcillin and clavulanic acid in premature low-birth-weight (less than 2,200 g) neonates with presumed sepsis. Eleven infants received 12 courses of ticarcillin-clavulanic acid at 75 mg/kg of body weight intravenously every 12 h. Blood samples were collected at 0.5, 1.5, 4, and 8 h following the infusion of the initial dose. The concentrations of ticarcillin and clavulanic acid were determined by a microbiologic assay. Median (interpatient coefficients of variation) values for the volume of the central compartment, total steady-state volume, distributional clearance, total clearance, and terminal elimination half-life for ticarcillin were 0.030 liter/kg (21%), 0.26 liter/kg (48%), 0.41 liter/h/kg (47%), 0.047 liter/h/kg (47%), and 4.2 h (45%), respectively. For clavulanic acid the parameters were 0.28 liter/kg (32%), 0.36 liter/kg (34%), 11 liters/h/kg (36%), 0.12 liters/h/kg (72%), and 1.95 h (40%), respectively. Our results suggest that the current dosing recommendations of 75 mg/kg every 12 h risk subtherapeutic clavulanic acid concentrations and that 50 mg/kg every 6 h is a more rational dosing strategy.

Preliminary experience with a modified Tenckhoff catheter for intraperitoneal chemotherapy.

This study reports our preliminary experience with a modified Tenckhoff catheter for intraperitoneal chemotherapy, primarily designed to be larger, longer, and have more perfusion holes. There were 137 catheters implanted in 125 ovarian cancer patients from June 1988 to December 1990, among which 116 were actually used for intraperitoneal chemotherapy. A total of 559 cycles of intraperitoneal chemotherapy was given with a range of 1 to 16 uses per catheter. There were seven infections (6.0%), four inflow obstructions (3.4%), three bowel perforations (2.6%), and one leakage (0.8%). Among patients with catheter infection, three had delayed bowel perforation. Although the incidence of inflow obstruction was reduced from 5.5 to 3.4%, the improvement did not reach statistical significance. The frequency of delayed bowel perforation and infection were similar to the literature experience of other catheters. An unused catheter should be removed to avoid this serious complication. Further study is needed to evaluate fully the performance of this catheter system.

The late somatosensory evoked potential in premature and term infants. II. Topography and latency development.

The maturation of latency and scalp voltage topography of the simultaneously bilateral somatosensory evoked potential was studied in 53 neurologically intact pre-term and term infants, from 31 to 40 weeks post-menstrual age. Four peaks (N1, P1, N2 and P2) were reliably identified in all infants. The latency of each peak decreased as the infants matured. Each peak had a unique voltage scalp topography that remained stable as infants matured, even though the maps changed in amplitude intensity. N2 was large, easily identifiable with a central peak, and extremely stable in topography, suggesting that it might be used to evaluate the functional status of the somatosensory cortex in pre-term and term infants who are at high risk for developing intracranial hemorrhage leading to abnormalities of tone and delays in motor development.

Fetal head molding. Diagnosis by ultrasound and a review of the literature.

Head molding refers to changes in cranial bone relationships that occur in response to external compression force. In the normal term labor with vertex presentation, the suboccipito-bregmatic diameter shortens and the mentovertical diameter lengthens. This is accomplished partially through the unbending or straightening of the parietal bones rather than the frequently taught mechanism of overlapping sutures. The occipital and frontal bones may also contribute by an inward movement of their apex, using their basal portions as a hinge. A locking mechanism may occur in protracted labors as the free edges of the cranial bones are forced into one another, preventing further molding and providing more protection for the fetal brain. The preterm skull has weaker material properties and wider sutures. Thus, more molding at lower pressures is possible and the protective effect of "locking" may not be operational. A case of extreme antenatal preterm fetal head molding discovered at ultrasound is presented as an introduction to review the literature regarding molding.

Indomethacin pharmacokinetics in neonates: the value of volume of distribution as a marker of permanent patent ductus arteriosus closure.

Indomethacin (INDO) pharmacokinetics were examined in 18 neonates on 19 occasions, before and after patent ductus arteriosus (PDA) closure. Patients received INDO as an initial dose of 0.25 mg/kg intravenously, and INDO serum concentrations were measured 2 and 8 h after the dose. Subsequent doses were individualized based on clinical response, toxicity, and INDO pharmacokinetics. PDA status was confirmed echocardiographically at the start and end of therapy. INDO pharmacokinetic parameters varied from dose-to-dose within the same patient, and wide interpatient variability was also observed. Pre- and post-PDA closure, only INDO volume of distribution differed significantly (p less than 0.001) with mean values of 0.36 (+/- 0.06) L/kg and 0.26 (+/- 0.08) L/kg. The reason for this occurrence remains unclear. However, a new application for pharmacokinetics as a probe of physiology is demonstrated.