Federica Freato

Brain Auditory Activation Measured by Near-Infrared Spectroscopy (NIRS) in Neonates

This study presents a new measure of the hemodynamic changes to an auditory stimulus in newborns. Nineteen newborns born at 28-41 wk and aged 1 to 49 d were studied in waking and/or sleeping state, for a median time of 4 min 40 s before, 2 min 40 s during, and 3 min 5 s after an acustic stimulus (tonal sweep of frequency increasing from 2 to 4 kHz, intensity 90 dB SPL) originating 5 cm from the external auditory meatus. The emitter and detector optodes were placed over the left or right temporal region, corresponding to T3 or T4 EEG electrodes. The concentration changes in cerebral chromophores Δ[HbO2], Δ[Hb] and Δoxidized-reduced cytochrome aa3 were recorded every 5 s. Changes in cerebral blood volume were calculated from the changes in total Hb × 0.89/large vessel Hb concentration. Increased oxyhemoglobin, Δ[HbO2], total Hb, Δ[Hb sum], and cerebral blood volume, ΔCBV, were found in 13/19 neonates, with the exception of a neonate who only had increased in Δ[Hb], Δ[Hb sum] and ΔCBV. During the stimulation phase there was a significant increase in ΔCBV (t test, p = 0.00006) in the responsive newborns from a mean value of 0.006 (±0.02) mL/100 g in the pretest phase to 0.09 (±0.06) mL/100 g during the auditory stimulus. After the test ΔCBV decreased to 0.04 (±0.07) mL/100 g (t test, p = 0.01), so did Δ[Hb sum] (p = 0.02). Hemodynamic responses of the subjects who showed increases in Δ[Hb sum] and Δ[HbO2] were analyzed to study the Δ[Hb]. The responder subjects could be classified into two groups according to Δ[Hb] changes: 8/13 (61.5%) showed an increase of Δ[Hb] (pattern A), while 5/13 (38.4%) showed a decrease (pattern B) (t test, p = 0.03). These two patterns did not show differences related to Δ[HbO2] and Δ[Hb sum]. The ΔCBV changes in nonresponders presented a decrease during the test phase (t test, p = 0.04). CBV did not return to pretest values, suggesting a fronto-temporal brain pathway for storing unusual sounds. The increase in CBV followed the local increase in oxyhemoglobin and total Hb concentrations due to a greater use of oxygen in the homolateral temporal cortex of the newborns.

Foot pulse oximeter perfusion index correlates with calf muscle perfusion measured by near-infrared spectroscopy in healthy neonates.

OBJECTIVE:In critically ill neonates, peripheral perfusion and oxygenation assessment may provide indirect information on the circulatory failure of vital organs during circulatory shock. The development of pulse oximetry has recently made it possible to calculate the perfusion index (PI), obtained from the ratio between the pulsatile and nonpulsatile signals of absorbed light. The main goals of this study were: (1) to study foot PI; and (2) to evaluate the relationship between foot PI, obtained continuously by pulse oximetry, and a number of variables, i.e. blood flow (BF), oxygen delivery (DO2), oxygen consumption (VO2), and fractional oxygen extraction (FOE), measured indirectly by near-infrared spectroscopy (NIRS) on the calf in 43 healthy term neonates (weight 3474.6±466.9 g; gestational age 39.1±1.4 weeks).STUDY DESIGN:Calf BF, DO2 and VO2 were assessed by NIRS on short-lived venous and arterial occlusion maneuvers. PI was measured on the contralateral foot.RESULTS:Foot PI was 1.26±0.39. There was a positive correlation between foot PI and both calf BF (r=0.32, p=0.03) and DO2 (r=0.32, p=0.03), but no correlation was found between foot PI and calf FOE and between foot PI and VO2.CONCLUSIONS:In the neonatal intensive care unit, continuously measuring foot PI by pulse oximetry seems clinically more feasible for peripheral perfusion monitoring than spot measurements of the calf BF and/or VO2 by indirect NIRS.

Home oxygen therapy in infants with bronchopulmonary dysplasia: assessment of parental anxiety

BACKGROUND It is conceivable that a complicated recovery course in a high-risk premature infant managed at home generates apprehension and anxiety in parents. AIMS We attempted to define the evolution of anxiety levels in a population of parents of low-birth-weight premature infants with bronchopulmonary dysplasia enrolled in a prospective home O(2) therapy program. STUDY DESIGN In the immediate pre-discharge [mean postnatal age 95 (45-158) days], a questionnaire (State-Trait Anxiety Inventory form Y) was given to all parents of the premature infants [mean birth weight 1106 (0.610-1.770) kg; mean gestational age 27.1 (24-31) weeks] present for the discharge. Subsequently, the parents were assessed twice, initially after a week from the discharge of their infants and then at the end of the oxygen therapy phase [mean postnatal age 185 (60-361) days]. They included 10 mothers and 10 fathers, aged 33.5+/-0.5 and 37+/-0.2 years, respectively. RESULTS Our results indicate that these parents present an increased state anxiety level upon hospital discharge of their oxygen-dependent premature infants, which decreases as the improvement of respiratory status and the cessation of oxygen-dependency become evident [mean+/-S.D. related to age (T) maternal values 47.1+/-7.0, 41.8+/-5.6, 39.1+/-4.7, respectively; mean+/-S.D. related to age (T) paternal values 42.2+/-8.5, 41.1+/-8.1, 40.5+/-8.2, respectively]. When assessed separately by parental gender, in the maternal group, state anxiety decreased significantly (ANOVA, p<0.05). CONCLUSIONS These data indicate that although neonatologists generally define the discharge of prematures with chronic lung disease based upon the acquired stabilization of vital parameters, in the oxygen-dependent group, they should also pay special attention to the emotional support of the parents who we have identified as being at increased risk for pre-discharge anxiety.

Influence of ventilation mode on neonatal cerebral blood flow and volume

BACKGROUND Cerebral hemodynamics is supposed to be influenced by the different ventilation approach. Ventilation support can be classified as non-invasive (N-CPAP) or invasive (SIMV and HFV), the last known to induce endotrauma. Our aim was the non-invasive NIRS assessment of neonatal absolute cerebral blood flow (CBF) and relative cerebral blood volume changes (DeltaCBV) during synchronized intermittent ventilation (SIMV), or high frequency ventilation (HFV) and nasal continuous positive airways pressure (CPAP). METHODS An observational study in a tertiary referral NICU. CBF and DeltaCBV changes were assessed in 41 preterm newborn infants with respiratory distress syndrome treated using mechanical ventilation or the CPAP device. RESULTS Basal chromophore traces enabled DeltaCBV (mL/100 g) changes to be calculated. CBF was calculated in mL/100 g/min from the saturation rise integral and rate of rise [O(2)Hb-HHb]. Median DeltaCBV was 0.07 (range 0.01-0.13) in SIMV group, 0.07 (0.01-0.19) in HFV group and 0.13 (0.10-1.28) in CPAP group. Median CBF was 14.44 (2.70-32.10), 9.20 (2.94-19.58) and 31.69 (13.59-34.93) respectively. A multiple regression model showed a significant correlation between DeltaCBV or CBF and ventilation approach. CONCLUSION In the light of our results, we might speculate that, assuming that hemodynamic autoregulation is safe and arterial blood pressure is preserved, ventilation per se influences brain circulation.

Neonatal meningitis due to a vertical transmission of Pasteurella multocida

of domestic animals, such as cats and dogs, and can be transmitted to humans from bites or scratches. Human diseases caused by P. multocida include: (i) cellulitis and lymphadenitis; (ii) chronic respiratory infections in patients with pulmonary disorders; and (iii) P. multocida often acts as an opportunistic pathogen with a predilection for causing bacteremia in patients with liver dysfunction, septic arthritis in damaged joints, central nervous system infections and meningitis in the very elderly or young, especially the newborn. Cases of neonatal meningitis acquired by vertical transmission are very unusual. We describe a case of neonatal infection acquired intrapartum from the mother’s vagina. Table 1 summarizes the literature regarding neonatal infections caused by P. multocida.1–20

Maternal anxiety upon NICU discharge of high-risk infants

Maternal anxiety and apprehension at various stages in pregnancy are associated with abnormal labour, dystocia, higher rates of foetal and maternal morbidity, and neonatal behavioural abnormalities. We have aimed to determine predischarge state and trait anxiety levels in a population of mothers of neonatal intensive care (NICU) discharged high-risk newborn infants, and to investigate whether predischarge maternal anxiety would be another negative consequence of complicated gestation, labour and puerperium. State and trait anxiety levels, using the State-Trait Anxiety Inventory (STAI), were examined in 100 consecutively enrolled mothers of third level NICU discharged high-risk infants and 100 control mothers of healthy babies discharged 4 days postpartum from the regular nursery. While trait anxiety levels were comparable between mothers of high-risk and healthy discharged newborns (age corrected values (T) 43.66±8.67 vs 43.70±7.25, respectively), state anxiety levels were significantly increased in the mother group of NICU discharged infants (age related values (T) 49.83±9.47 vs 46.68±8.58, respectively; p<0.05). In addition, state anxiety levels, in the mother groups associated to peripartal emotional distress or to delayed high-risk newborn discharge, significantly correlated (r=0.610; p<0.001) with personal trait anxiety levels. These data indicate that mothers with higher trait anxiety will react stronger to the emotional challenges of the NICU treatment, resulting in elevated levels of state anxiety. The implications for the development of high-risk infants are discussed.

Impact of anxiety in the puerperium on breast-feeding outcomes: role of parity.

Objective: Studies in animals indicate that stress and anxiety can depress lactation, but there is much less information available concerning humans. We aimed to determine whether maternal anxiety in puerperium, potentially exacerbated by the primiparity inexperience, has a negative impact on breast-feeding outcomes. Subjects and Methods: The state-trait anxiety inventory Y form (Spielberger, 1983) was administered to a total of 204 mothers, 101 primiparae, and 103 pluriparae on the third to fourth day postpartum. Results: We found that primiparae had state anxiety (T) scores significantly higher than pluriparae (44.57 ± 5.85 vs 43.28 ± 7.10, P = 0.03). Increased state anxiety levels impaired breast-feeding success. In addition, in the logistic regression analysis model used to assess factors predictive of breast-feeding longer than 3 months, maternal state anxiety was the most significant risk factor (odds ratio 0.99; 0.88–0.98, P < 0.01). Conclusions: In the puerperium, anxiety, potentially exacerbated by primiparae inexperience, is associated with impaired lactation. Alleviating maternal anxiety could be beneficial for stimulating breast-feeding in more vulnerable women.

Effect of postpartum anxiety on the colostral milk b-endorphin concentrations of breastfeeding mothers

Peripartal maternal apprehension and anxiety are associated with abnormal labour, dystocia and higher rates of fetal and maternal morbidity. Since colostral beta-endorphin ( g -EP) concentrations are twofold higher than circulating levels, we hypothesised that substantial maternal emotional distress in puerperium might induce consistent changes in colostral beta endorphin galactopoiesis. To test this hypothesis, we assessed the effects of postpartum maternal anxiety (State-Trait Anxiety Inventory-Y form, Spielberger CD, Palo Alto, CA, USA, 1983) on colostral milk g -EP levels ( g -endorphin 125 I RIA, INCSTAR Corporation-Stillwater, Minnesota, USA) in a population of healthy lactating mothers, on the fourth postpartum discharge day, 14 after at term vaginal delivery, 14 after premature ( S 34 <37 gestational weeks) vaginal delivery, and 14 after elective cesarean section. The colostral milk g -EP concentrations of mothers who vaginally delivered at term or prematurely were significantly higher on the fourth postpartum day (6·0 - 0·5 and 6·6 - 0·7 vs. 4·3 - 0·4 pmol/l, respectively; P <0·05) than colostral levels of mothers who underwent caesarean section. At the same time, while trait anxiety levels (T, age corrected values) were unaffected by route and mode of delivery, in mothers presenting increased colostral milk g -EP galactopoiesis after vaginal delivery there was a statistically significant negative correlation ( r -0·40; P <0·03) between colostral milk g -EP concentrations and trait anxiety levels. These data indicate that the labour pain and the vaginal delivery process play a central role in increasing colostral opioid availability for the breastfed neonate; peripartal maternal anxiety is a negative psychobiological determinant in opioid galactopoiesis, and possibly in the postnatal development of several related biological functions of growing infants.Peripartal maternal apprehension and anxiety are associated with abnormal labour, dystocia and higher rates of fetal and maternal morbidity. Since colostral beta-endorphin (beta-EP) concentrations are twofold higher than circulating levels, we hypothesised that substantial maternal emotional distress in puerperium might induce consistent changes in colostral beta endorphin galactopoiesis. To test this hypothesis, we assessed the effects of postpartum maternal anxiety (State-Trait Anxiety Inventory-Y form, Spielberger CD, Palo Alto, CA, USA, 1983) on colostral milk beta-EP levels (beta-endorphin 125I RIA, INCSTAR Corporation-Stillwater, Minnesota, USA) in a population of healthy lactating mothers, on the fourth postpartum discharge day, 14 after at term vaginal delivery, 14 after premature (> or = 34 <37 gestational weeks) vaginal delivery, and 14 after elective cesarean section. The colostral milk beta-EP concentrations of mothers who vaginally delivered at term or prematurely were significantly higher on the fourth postpartum day (6.0+/-0.5 and 6.6+/-0.7 vs. 4.3+/-0.4 pmol/l, respectively; P <0.05) than colostral levels of mothers who underwent caesarean section. At the same time, while trait anxiety levels (T, age corrected values) were unaffected by route and mode of delivery, in mothers presenting increased colostral milk beta-EP galactopoiesis after vaginal delivery there was a statistically significant negative correlation (r-0.40; P <0.03) between colostral milk beta-EP concentrations and trait anxiety levels. These data indicate that the labour pain and the vaginal delivery process play a central role in increasing colostral opioid availability for the breastfed neonate; peripartal maternal anxiety is a negative psychobiological determinant in opioid galactopoiesis, and possibly in the postnatal development of several related biological functions of growing infants.

429 Early- Versus Late-Cord Clamping: Hemodynamic Effects in Healthy Term Newborn Infants.

Aim: To evaluate whether clamping time could affect peripheral and heart hemodynamics, in a group of healthy term newborns.Subjects and Methods: We evaluated 9 early cord clamping (ECC) (30 seconds) in comparison with 10 late cord clamping neonates (LCC) (4 minutes) at the mean age of 68.7 hrs. The following variables were evaluated: hematocrit (Ht %), hemoglobin (Hb g/dL), total bilirubin (TB mg/dL), heart left diastolic ventricular diameter LDV(D) (cm) by a sonographer (HDI 3000 CV); calf blood flow (mL/100g/min), calf Hb flow (micromoles/100 mL/min), calf O2 delivery (DO2), O2 consumption (VO2) (micromoles/100 mL/min), using near-infrared spectroscopy (NIRS, NIRO 300 oximeter). Perfusion index (PI) were obtained using a Masimo SET radical pulse oximeter with a sensor placed on the foot contralateral. Data are presented as mean (SD). Mann Whitney test was used to compare the two groups values. A p value less than 0.05 was considered significant.Results: Ht 55.5 (4.8) vs 64.5 (5.3) (p 0.004) in ECC and LCC groups respectively, Hb 15.2 (1.2) vs 17.9 (1.4) (p 0.002), TB 8.2 (3.6) vs 7.3 (2.8) (ns), calf Hb flow 2.1 (1.4) vs 1.9 (0.9) (ns), calf BF 0.7 (0.4) vs 0.7 (0.3) (ns), calf DO2 10.1 (1.3) vs 11.2 (1.1) (ns), calf VO2 calculated by arterial occlusion 0.4 (0.1) vs 0.3 (0.1) (ns), LDV(D) 1.5 (0.08) vs 1.7 (0.1) (p 0.01), and foot PI 1.08 (0.3) vs 1.1 (0.3) (ns).Conclusion: Our study shows that LCC group has an increased placental transfusion, that was expressed by higher hematocrit and hemoglobin, in comparison with ECC group; so a bigger left ventricle diameter at the diastole. There was no evidence of changing in both calf Hb flow and blood flow, as well as in oxygen tissue metabolic demand and foot PI. The increased blood volume seems not to increase the jaundice risk.

428 Role of Cerebral Blood Volume, Tissue Oxygenation Index, Troponin I and Neuro-Physiological Variables in Birth Asphyxia, Related to Outcome.

AIM: To evaluate cerebral blood volume (DCBV), tissue oxygenation index (TOI), troponin I and neuro-physiological variables in term neonates affected at birth by cardiorespiratory depression or asphyxia and their correlation with outcome.DESIGN/METHODS: Case-control study. Inclusion criteria: arterial pH less or equal to 7.25, excessive base deficit (BE) and Apgar at 5 min less or equal to 6. We evaluated grade of encephalopathy (HIE) at birth as well as neurodevelopmental performance at 12 months. The 15 control neonates were with Apgar score more or equal to 9 at 5 min, with near infrared spectroscopy (NIRS) and troponin I at the same age. Optodes were placed on the frontotemporal area in the first 14±7.6h after birth. DCBV was calculated from D[Hb sum]x0.89/Hb (g/dL). We assessed troponin I and blood gases (before 1 hour of life) on admission. Brain ultrasound (US) were performed at 24 hours and somatosensory evoked potentials (EP), at 2 weeks of life. Data are presented as mean±SD.RESULTS: Troponin I increased in the asphyxiated or depressed group in comparison with controls (0.39±0.54 vs 0.09±0.08, p=0.04) (Mann-Whitney test). ANOVA analysis showed a correlation between HIE grade at birth with EEG (p=0.03), EP (p=0.00009), US (p=0.009). A multiple regression model, including EEG, US and EP as independent variables and one year-outcome as dependent one, presents for EP a p=0.02 and Beta 0.57. Another multiple regression model including pH, BE, troponin I as well as DCBV and TOI as independent variables and one year-outcome shows for BE a p =0.008.CONCLUSION: In asphyxiated or depressed term newborn infants EEG, EP and US scan correlated with grade of HIE at birth. EP and BE correlated with one year outcome. DCBV and TOI seem not to indicate early and one-year outcome.