Transport risk index of physiologic stability: a practical system for assessing infant transport care.

OBJECTIVES: To develop and validate a practical, physiology-based system for assessment of infant transport care. STUDY DESIGN: Transport teams prospectively collected data, before and after transport, from 1723 infants at 8 neonatal intensive care units (NICUs) from 1996 to 1997. We used logistic regression to derive a prediction model for mortality within 7 days of NICU admission and develop the Transport Risk Index of Physiologic Stability (TRIPS). We validated TRIPS for prediction of 7-day mortality, total NICU mortality (until discharge), and severe (> or =grade 3) intraventricular hemorrhage. RESULTS: TRIPS comprises 4 empirically weighted items (temperature, blood pressure, respiratory status, and response to noxious stimuli). TRIPS discriminated 7-day NICU mortality and total NICU mortality from survival with receiver operating characteristic areas of 0.83 and 0.76, respectively. There was good calibration across the full range of TRIPS scores and gestational age groups. Increase and decrease in TRIPS scores after transport were associated with increased and decreased mortality, respectively. The receiver operating characteristic area for TRIPS prediction of severe intraventricular hemorrhage was 0.74. Addition of TRIPS improved performance of prediction models in which gestational age and baseline population risk variables were used. CONCLUSIONS: TRIPS is validated for infant transport assessment.

Variations in intraventricular hemorrhage incidence rates among Canadian neonatal intensive care units.

OBJECTIVES: To examine the variation in intraventricular hemorrhage (IVH) incidence among neonatal intensive care units and identify potentially modifiable risk factors. STUDY DESIGN: Multiple logistic regression analysis was used to examine variations in > or =grade 3 IVH, adjusting for baseline population risk factors, admission illness severity, and therapeutic risk factors. Subjects were born at <33 weeks' gestational age, admitted within 4 days of life to 1 of 17 participating Canadian NICU network sites in 1996-97, and had neuroimaging in the first 2 weeks of life. RESULTS: Of 5126 subjects <33 weeks' gestational age, 3806 had neuroimaging reports. Five of 17 sites had significantly (P <.05) different crude incidence rates of grade 3-4 IVH (odds ratios [OR] 0.2, 3.2, 2.6, 2.1, 1.9) than the hospital with median incidence. With adjustment for baseline population risk factors, perinatal risks, and admission illness severity, IVH incidence rates remained significantly (P <.05) higher at 3 sites (OR 2.9, 2.3 and 2.1). Inclusion of therapy-related variables (treatment of acidosis and vasopressor use on the day of admission) in the model eliminated all site differences. CONCLUSIONS: IVH incidence rates vary significantly. Patient characteristics explain some of the variance. Early treatment of hypotension and acidosis and mode of delivery are potentially modifiable factors and warrant further study in IVH prevention.

SNAP-II and SNAPPE-II: Simplified newborn illness severity and mortality risk scores.

OBJECTIVES: Illness severity scores for newborns are complex and restricted by birth weight and have dated validations and calibrations. We developed and validated simplified neonatal illness severity and mortality risk scores. The primary outcome was in-hospital mortality. STUDY DESIGN: Thirty neonatal intensive care units in Canada, California, and New England collected data on all admissions during the mid 1990s; patients moribund at birth or discharged to normal newborn care in <24 hours were excluded. Starting with the 34 data elements of the Score for Neonatal Acute Physiology (SNAP), we derived the most parsimonious logistic model for in-hospital mortality using 10,819 randomly selected Canadian cases. SNAP-II includes 6 physiologic items; to this are added points for birth weight, low Apgar score, and small for gestational age to create a 9-item SNAP-Perinatal Extension-II (SNAPPE-II). We validated SNAPPE-II on the remaining 14,610 cases and optimized the calibration. RESULTS: In all birth weights, SNAPPE-II had excellent discrimination and goodness of fit. Area under the receiver operator characteristic curve was .91 +/- 0.01. Goodness of fit (Hosmer-Lemeshow) was 0.90. CONCLUSIONS: SNAP-II and SNAPPE-II are empirically validated illness severity and mortality risk scores for newborn intensive care. They are simple, accurate, and robust across populations.

Effect of cardiac arrest time on cortical cerebral blood flow during subsequent standard external cardiopulmonary resuscitation in rabbits.

Standard external cardiopulmonary resuscitation (SECPR) produces high cerebral venous and intracranial pressure peaks, low cerebral perfusion pressure, and low cerebral blood flow (CBF). Cerebral viability seems to require 20% of normal CBF, which SECPR cannot reliably generate. We tested the hypothesis that SECPR can produce adequate CBF if started immediately, but not if started after a long period of cardiac arrest (no flow, stasis). Cardiac arrest times of 1, 3, 5, 7 and 9 min were studied in rabbits. We measured unifocal cortical CBF with H2 clearance curves after saturation with H2 10%, O2 50% and N2O 40% by intermittent positive-pressure ventilation (IPPV). Measurements were made during spontaneous circulation (control condition), and then after resaturation immediately before induction of asystole by KCl i.v., and H2 clearance starting at end of arrest time during SECPR-basic life support with IPPV 100% and manual chest compressions (120/min) during asystole. Control cortical CBF was 30-40 ml/100 g brain per min. During asystole and SECPR, CBF greater than 20% normal was achieved only after no-flow of 1 min. After longer arrest (no-flow) times, CBF was less than 20% normal. Values were near zero after 7 and 9 min of cardiac arrest. Decrease in mean arterial pressures (MAP) produced by SECPR during asystole paralleled CBF values. Thus, the longer the preceding period of stasis, the lower the MAP and CBF generated by SECPR without epinephrine. This effect may be the result of anoxia-induced vasoparalysis and stasis-induced increased blood viscosity.

Idiopathic membranous glomerulopathy preceding the emergence of systemic lupus erythematosus in two children.

An idiopathic nephrotic syndrome associated with membranous glomerulopathy antedated the subsequent emergence of systemic lupus erythematosus in two patients (7-year-old and 14-year-old girls). At the onset of INS, there was neither clinical evidence of multisystem disease nor unequivocal serologic evidence of SLE. The only early possible indication of SLE was the presence of microtubular inclusions in glomerular endothelial cells on electron microscopy. In each instance (one year and three years after onset of INS), a second renal biopsy showed transformation of the membranous glomerular lesion to a more florid type with glomerular subendothelial dense deposits. One patient died of overwhelming pulmonary infection while she was receiving prednisone and cyclophosphamide; the other developed progressive renal failure despite steroid treatment. SLE should be considered in patients presenting with apparent idiopathic MG, in whom nephrotic syndrome persists. Intraendothelial cell microtubular inclusions may be an early clue to later emergence of SLE.