Allen Erenberg

Appliance for stabilizing orogastric and orotracheal tubes in infants.

The long-term use of orotracheal tubes in infants has been associated with airway damage, palatal groove formation, acquired cleft palate, and defective primary dentition. Nasotracheal intubation is associated with trauma to the nasal septum and deformities of the nares. Because the infant is an obligatory nose-breather, nasogastric feeding tubes obstruct the nares and cause mucosal edema. We have developed an intraoral appliance designed to stabilize orogastric feeding and orotracheal tubes, and prevent obstruction to the nares and trauma to the palate and alveolar ridge.

Pulmonary mechanics in healthy term neonates: Variability in measurements obtained with a computerized system

Using a commercially available computer-based analysis of ventilation and esophageal pressure (PeDs), we studied 11 healthy term neonates with serial pulmonary mechanics measurements during the first 3 days of life to determine the intrasubject variability of repeated measurements. Three consecutive pulmonary function tests were obtained before and after repositioning of the esophageal catheter, for a total of six measurements per day in each subject. The daily coefficient of variation for these 11 subjects ranged from 6% to 32% for respiratory rate; 6% to 27% for tidal volume; 3% to 28% for specific dynamic compliance, and 11% to 69% for pulmonary resistance. Repositioning the esophageal catheter did not produce significant differences in measurements of pulmonary mechanics (p greater than 0.05). We conclude that within a given subject, the maximum variability (mean + 2 SD) was 28% for specific dynamic compliance and 56% for pulmonary resistance. These intrasubject variability limits are important when one is interpreting pulmonary mechanics measurements in neonates before and after specific treatment, such as bronchodilators, diuretics, surfactant, or steroids.

Imaging evaluation of breast-feeding and bottle-feeding systems

OBJECTIVEnTo compare infant sucking and swallowing patterns during feeding with a new artificial nipple and during breast-feeding.nnnMETHODSnFifteen healthy, term infants were fed successfully for 1 week with use of the new tricut nipple; then each infants oral cavity was examined during feeding by using real-time ultrasonography. Measurements of nipple length and compression were made, together with observations concerning the integrity of the seal formed by the infants mouth around the nipple. These data were compared with similar data from previous studies of 16 breast-fed infants.nnnRESULTSnAlthough no artificial feeding system exactly simulates breast-feeding, the new tricut nipple was sucked in a manner similar to the way the human nipple is sucked and delivered milk posteriorly to the foramen cecum region of the tongue, just as the breast does.nnnCONCLUSIONnAlthough further studies are necessary, to evaluate other characteristics of the new tricut nipple, the measurements from this investigation are useful additions to the ultrasound data these investigators have accumulated on various artificial feeding systems. These data may also prove helpful in determining the most appropriate nipples for infants with various feeding disorders.

Influence of infusion pumps on the pharmacologic response to nitroprusside.

ObjectiveTo compare the relationship between variability in nitroprusside delivery from five infusion pumps and the resulting variability in mean arterial pressure (MAP). DesignRandomized, crossover study design. SettingA pediatric ICU in a university hospital. PatientsInformed parental consent was obtained for six patients who were hemodynamically stable and receiving a continuous nitroprusside infusion for a clinical application. Subjects ranged in age from 11 months to 9 yr. InterventionsAll of the subjects were administered nitroprusside using selected infusion pumps, which included Abbott (Micro), 3M/AVI (210), IMED (965), IVAC (565), and Kendall McGraw (MicroRate). Measurements and Main ResultsAfter an initial equilibration interval for each device, MAP was measured and recorded at 10-sec intervals for ≥90-min intervals using a computerized data collection technique. Variation in nitroprusside administration (flow continuity) for each infusion pump was determined in vitro using a computerized gravimetric technique. Variation in both MAP and flow continuity was mathematically expressed as the coefficient of variance (CV) of the measured values for each of the respective infusion pumps. For the Abbott, IMED, 3M/AVI, IVAC, and Kendall McGaw infusion pumps, mean ± SD continuity CV values were 85 ± 31%, 39 ± 26%, 19 ± 8%, 17 ± 3%, and 12 ± 3%, respectively, and MAP CV values were 18 ± 21%, 15 ± 11%, 8 ± 2%, and 16 ± 10%, respectively. ConclusionAn apparent direct relationship between MAP variability and flow continuity was observed. We speculate that variation in effect of potent short-acting drugs may, in part, be due to infusion pump operation. (Crit Care Med 1991; 19:98)

Flow rate variability from electronic infusion devices

During continuous drug administration to pediatric patients, unfavorable pharmacologic effects have occurred. These effects were attributed to variations in flow from electronic infusion devices (EIDs). The intent of this investigation was to evaluate the influence of microrate (0.1 to 99.9 ml/h) EID on the accuracy, continuity, and pattern of flow of continuously effused fluid. Using a factorial study design, iv fluid was effused through iv delivery systems using combinations of five microrate EIDs, three iv flow rates, and three sample-collection intervals. Serial weights were measured at the appropriate sample-collection time using a computerized gravimetric technique to determine accuracy, continuity, and pattern of flow. All the EIDs produced accurate flow within 5% of the desired rate of 5 and 10 ml/h. At 1 ml/h, the actual iv flow rate ranged from 65.1% to 91% of the desired rate. Each of the respective EIDs produced various levels of flow continuity; each flow pattern characterized the mechanism of pump operation for each device. Thus, alteration in response (e.g., increased toxicity or decreased efficacy) to a continuous drug infusion must not be attributed exclusively to the drug or clinical condition of the patient. Serious consideration should also be given to the method of drug delivery and, in particular, the continuity of flow that results from a particular EID.

Decreased flow accuracy from volumetric infusion pumps.

Accurate flow from infusion pumps should be maintained when exposed to a variety of clinical conditions. The intent of this study was to evaluate in vitro flow rate accuracy of three infusion pumps subjected to the influences of variable back-pressure, solution viscosity, and infusion rates. A factorial study design was selected to determine the influence of three flow rates (5, 10, and 20 ml/h), three back-pressures (100, 200, and 300 mm Hg), and two solution viscosities (5%, 25% dextrose in water) on flow rate accuracy from three infusion pumps (Abbott 4P, IVAC 560, and Travenol 6200) using a standard gravimetric technique. Mean +/- SD accuracy values were -9.4 +/- 6.4% (range -29.1 to -0.7), 0.5 +/- 2.2% (range -4.2 to 6.3), and -0.5 +/- 4.7% (range -8.5 to 9.9) of the desired rate for the Abbott, IVAC, and Travenol devices, respectively. Back-pressure was the only factor to influence significantly flow accuracy for the Abbott device (r = .81). All factors significantly influenced accuracy for the Travenol device (r = .55). No factor influenced accuracy for the IVAC infusion pump. Both the IVAC 560 and Travenol 6200 have acceptable flow accuracy values within the range of study factors examined. The Abbott 4P had significant decreases in flow accuracy in response to increasing back-pressure.

In utero Bladder Diversion – Problems with Patient Selection

Based upon the concept that an obstruction-maldevelopment sequence is reversible after diversion, it has been suggested that the fetus with a bladder outlet obstruction is a potential candidate for in utero intervention. We report an infant who had both renal and pulmonary dysplasia at birth despite a technically successful diversion at 22 weeks gestation. The poor outcome suggests that the organ damage either occurs so early that it precludes corrective surgery, or that the maldevelopment is not the result of obstruction, but rather a primary mesodermal defect.

Results of the First Double Blind Placebo (Pl) Controlled Study of Caffeine Citrate (Cc) for the Treatment of Apnea of Prematurity (Aop) † 1001

Results of the First Double Blind Placebo (Pl) Controlled Study of Caffeine Citrate (Cc) for the Treatment of Apnea of Prematurity (Aop) † 1001

Caffeine Pharmacokinetics (PK) In Premature Infants With Apnea of Prematurity(AOP) 340

Objective: To estimate caffeine PK in premature infants during a clinical evaluation of sterile caffeine citrate (CC) for prevention of AOP.