Paresh B. Pandit

Predischarge monitoring of preterm infants

The objectives of this study were: 1) to perform documented event‐monitoring (DEM) for apnea (A, ⩾20 s) and bradycardia (B, <80 beats per min for ⩾5 s) in premature infants prior to discharge, and 2) to examine the accuracy of nursing documentation (ND) of A and B. Forty‐four stable preterm infants, with mean weights and gestational ages at birth (± SD) of 1,543 (± 365) g, and 30 (± 2) weeks, respectively, were studied using DEM for 9 (± 2) days prior to discharge. Differences in DEM and ND were analyzed by the z‐test for proportions.

Inspiratory Work of Breathing (WOB) with a Demand Flow Vs Constant Flow Nasal Continuous Positive Airway Pressure (NCPAP) Device in Preterm Neonates

Inspiratory Work of Breathing (WOB) with a Demand Flow Vs Constant Flow Nasal Continuous Positive Airway Pressure (NCPAP) Device in Preterm Neonates

Respiratory Inductance Plethysmography (RIP) for Assessment of Lung Volume Changes (|[Delta]|VL) During High Frequency Oscillatory Ventilation (HFOV)|[dagger]| 1183

A clinically applicable and reliable method to assess ΔVL in infants on HFOV could be of value to neonatologists when attempting to optimize gas exchange. We hypothesized that lung volume recruitment, ΔVL, could be accurately measured in both normal and saline-lavage induced RDS, using DC-coupled RIP. In five anesthetized, paralyzed and tracheostomized piglets(wt: 2-4 kg, age: 5-10 days), we compared estimates of ΔVL measured simultaneously by RIP and body plethysmography (PL) before and after saline lung lavage. HFOV (SensorMedics 3100) settings were 8 Hz and pressure amplitudes of 50 pre- and 60 cmH2O post-lavage. Mean airway pressures (Paw) were varied between 6-14 and 10-26 cmH2O pre- and post-lavage respectively. Estimates of ΔVL from RIP and PL were in close agreement pre-and post-lavage, both: 1) during active recruitment (R=0.83-0.97; slope=0.76-1.16); and 2) at steady state (see example ΔVL @ Plateau, Figure). We conclude that RIP may have clinical application for determining optimal ΔVL during HFOV, thereby avoiding lung under- and over-distension.

Lung Mechanics Measurements in Preterm Neonates: Effects of Breathing Pattern and Patient Characteristics 1715

Lung Mechanics Measurements in Preterm Neonates: Effects of Breathing Pattern and Patient Characteristics 1715

Outcome Following Pulmonary Hemorrhage (PH) in Very Low Birth Weight Neonates Treated with Surfactant. † 1232

Outcome Following Pulmonary Hemorrhage (PH) in Very Low Birth Weight Neonates Treated with Surfactant. † 1232

Effects of Maturation on Changes in Lung Mechanics During Continuous Intravenous Infusion of Histamine in Piglets. 1796

Background. Increases in lung resistance (RL) due to i.v. histamine bolus are reported to become more pronounced with postnatal maturation (Dreshaj et al; J. Appl. Physiol. 81(4): 1785-1791, 1996). Objective. To determine if postnatal development affects the changes in RL and lung elastance (EL =1/compliance) during constant infusion of histamine. Methods. We continuously measured airway opening pressure (Pao), flow and esophageal pressure (Pes) during 30-minute intravenous infusions of histamine in seven tracheostomized, anesthetized, paralyzed and mechanically ventilated (constant tidal volume) piglets [3 newborn (4-6 days, 2.5-3.0 Kg) and 4 weaned (8 weeks, 12.3-18 Kg)]. Measurements were repeated at two concentrations (0.5 and 5.0 μg/Kg/min). RL and EL were determined by multiple linear regression; i.e., Pao(t)-Pes(t)=RL·flow(t) + EL·volume(t). Results. For both groups, RL and EL increased with histamine in a dose dependent fashion. The increases in EL were comparable regardless of dose. Changes in RL were similar at the lower histamine dose (figure). At the higher dose, the increases in RL were similar during early infusion ( 10 min) in older piglets. Conclusion. Differences in the response to histamine, in older versus newborn piglets, were only evident as a sharper rise in RL during the latter part of the higher dose infusion. Such age dependence of RL is consistent with histamine bolus data. We speculate that this phenomenon may be related to increased central airway involvement in the response as opposed to a predominantly peripheral effect because: 1) the sharp rise in RL did not coincide with a similar increase in EL, and 2) rise in RL only occurs late, when accumulation of histamine may have led to bolus-like conditions. Supported in part by an equipment grant from Novametrix Medical Systems Inc.