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Ventricular Output (ventricular + output)
Selected AbstractsPatent ductus arteriosus and cystic periventricular leucomalacia in preterm infantsACTA PAEDIATRICA, Issue 3 2001P Pladys Aim: To test the association between early disturbances in hemodynamics induced by left-to-right shunting through the duct and cystic periventricular leucomalacia. Patients: Forty-six preterm infants (27,32 wk) admitted to the neonatal intensive care unit with risk criteria. Methods: Patent ductus arteriosus was evaluated on days 1 and 4, and was significant (sPDA) in cases of absent or reversed end diastolic flow in the subductal aorta. Resistance index was measured in the anterior cerebral artery and in the subductal aorta. Main outcome: Diagnosis of cystic periventricular leucomalacia between day 10 and day 50. Results: The 12 infants who developed cystic periventricular leucomalacia were compared with those who did not. On day 1, sPDA was more frequent (64% vs 26%; p= 0.03) in the cystic periventricular leucomalacia group, left ventricular output was higher (median = 341 vs 279mlkg -1.min -1; p= 0.005), and rescue surfactant was more frequently used (83% vs 47%; p= 0.03). This latter association was confirmed by multivariate analysis. Resistance index in the anterior cerebral artery was increased in cases of significant patent ductus arteriosus (p < 0.01) and was correlated with resistance index in the subductal aorta. Conclusion: On day 1 in this selected population, sPDA has an effect on blood flow velocity waveform in cerebral arteries and is associated with an increase in the emergence of cystic periventricular leucomalacia. This association could be casual rather than causal. [source] Cardiocirculatory effects of patent ductus arteriosus in extremely low-birth-weight infants with respiratory distress syndromePEDIATRICS INTERNATIONAL, Issue 3 2003Senji Shimada Abstract Background:,Cardiocirculatory effects of hemodynamically significant patent ductus arteriosus (hsPDA) have not been systematically studied in extremely low-birth-weight (ELBW) infants with respiratory distress syndrome (RDS). The objective of the present study was to evaluate the effects of hsPDA on the left ventricular output (LVO) and organ blood flows in ELBW infants with RDS. Methods:,Extremely low-birth-weight infants (birth-weight <1000 g) treated with surfactant for RDS were studied by serial Doppler flow examinations. Doppler flow variables in 19 infants in whom hsPDA developed (hsPDA group) were compared with those in 19 infants without hsPDA matched for gestational age, birth-weight, and postnatal age (non-hsPDA group). All infants in the hsPDA group had pharmacologic closure of ductus arteriosus when hsPDA developed. Results:,Before pharmacological closure of PDA, the hsPDA group had significantly higher LVO, lower blood flow volume of the abdominal aorta, and lower mean blood flow velocities in the celiac artery, superior mesenteric artery, and renal artery than the non-hsPDA group. These alterations in the hsPDA group reverted to the levels in the non-hsPDA group after the closure of PDA and had no deleterious effects on the cardiorespiratory status. No significant differences between the groups were found in mean blood flow velocities of the anterior cerebral artery throughout the study period. Conclusion:,These results indicate that although LVO is increased, the splanchnic and renal blood flows are decreased when hsPDA develops in ELBW infants with RDS. The effects of these alterations of LVO and organ blood flows on the cardiorespiratory course seem to be minor when early pharmacologic closure of PDA is done. [source] The Role of Diastolic Pump Flow in Centrifugal Blood Pump HemodynamicsARTIFICIAL ORGANS, Issue 9 2001Takehide Akimoto Abstract: We tried to verify the hypothesis that increases in pump flow during diastole are matched by decreases in left ventricular (LV) output during systole. A calf (80 kg) was implanted with an implantable centrifugal blood pump (EVAHEART, SunMedical Technology Research Corp., Nagano, Japan) with left ventricle to aorta (LV-Ao) bypass, and parameters were recorded at different pump speeds under general anesthesia. Pump inflow and outflow pressure, arterial pressure, systemic and pulmonary blood flow, and electrocardiogram (ECG) were recorded on the computer every 5 ms. All parameters were separated into systolic and diastolic components and analyzed. The pulmonary flow was the same as the systemic flow during the study (p > 0.1). Systemic flow consisted of pump flow and LV output through the aortic valve. The ratio of systolic pump flow to pulmonary flow (51.3%) did not change significantly at variable pump speeds (p > 0.1). The other portions of the systemic flow were shared by the left ventricular output and the pump flow during diastole. When pump flow increased during diastole, there was a corresponding decrease in the LV output (Y = ,1.068X+ 51.462; R,2 = 0.9501). These show that pump diastolic flow may regulate expansion of the left ventricle in diastole. [source] Does caffeine impair cerebral oxygenation and blood flow velocity in preterm infants?ACTA PAEDIATRICA, Issue 9 2010MB Tracy Abstract Aim:, The aim of the study is to assess the effects of an intravenous 10 mg/kg loading dose of caffeine base in cerebral oxygenation, cerebral Doppler blood flow velocity and cardiac output in preterm infants. Methods:, Preterm neonates <34 weeks gestation were investigated at 1 and 4 h following the loading dose of caffeine using Doppler cerebral sonography, cardiac echocardiography and cerebral spatially resolved near-infrared spectroscopy. Results:, Forty infants were studied with a mean gestational age (mean ± standard deviation) of 27.7 (±2.5) weeks, birth weight of 1155 (±431) g and a postnatal age of 2.8 (±2.2) days. Mean Anterior Cerebral Artery peak and time average mean blood flow velocity fell significantly by 14% and 17.7%, respectively at 1 h post-caffeine loading dose, which recovered partially by 4 h. Cerebral Tissue Oxygenation Index fell from pre-dose levels by 9.5% at 1 h with partial recovery to 4.9% reduced at 4 h post-dose. There were no significant changes in left or right ventricular output, transcutaneous oxygen saturation, transcutaneous PCO2 or total vascular resistance. Conclusions:, A loading dose of 10 mg/kg caffeine base resulted in significant reduction at 1 h post-dose in cerebral oxygenation and cerebral blood flow velocity with partial recovery at 4 h. [source] Cerebral tissue oxygenation index and superior vena cava blood flow in the very low birth weight infantACTA PAEDIATRICA, Issue 1 2009M Moran Abstract Background: Superior vena cava (SVC) flow assesses blood flow from the upper body, including the brain. Near infrared spectroscopy (NIRS) provides information on brain perfusion and oxygenation. Aim: To assess the relationship between cerebral tissue oxygenation index (cTOI) and cardiac output measures in the very low birth weight (VLBW) infant in the first day of life. Methods: A prospective observational cohort study. Neonates with birth weight less than 1500 g (VLBW) were eligible for enrollment. Newborns with congenital heart disease, major congenital malformations and greater than Papile grade1 Intraventricular Haemorrhage on day 1 of life were excluded. Echocardiographic evaluation of SVC flow was performed in the first 24 h of life. Low SVC flow states were defined as a flow less than 40 mL/kg/min. cTOI was measured using NIRO 200 Hamamatsu. Results: Twenty-seven VLBW neonates had both echocardiography and NIRS performed. The median (range) gestation was 29/40 (25 + 3 to 31 + 5 weeks) and median birth weight was 1.2 kg (0.57,1.48 kg). The mean (SD) TOI was 68.1 (7.9)%. The mean (SD) SVC flow was 70.36(39.5) mLs/kg/min. The correlation coefficient of cerebral tissue oxygenation and SVC flow was r = 0.53, p-value 0.005. There was a poor correlation between right and left ventricular output and cTOI which is not surprising considering the influence of intra- and extracardiac shunts. Conclusion: There is a positive relationship between cerebral TOI values and SVC flow in the very low birth infant on day one of life. [source] Is serum troponin T a useful marker of myocardial damage in newborn infants with perinatal asphyxia?ACTA PAEDIATRICA, Issue 2 2007S. Costa Abstract Aim: To assess the correlation of echocardiographic signs of myocardial damage to serum cardiac troponin T (cTnT) concentrations in newborn infants with perinatal asphyxia. Methods: Electocardiograms (ECG) and echocardiograms (Echo) were obtained during the first 24 h of life from 29 asphyxiated and 30 control infants and correlated with cTnT concentrations. The echocardiographic parameters included systolic ventricular performance, preload, afterload, diastolic function, stroke volume (SV), left ventricular output (LVO), hyperechogenity of the papillary muscles and insufficiency of the atrioventricular valves. Results: LVO and SV were lower but CTnT were significantly higher in asphyxiated than in control infants: 0.15 (010,0.23) vs. 0.05 (0.02,0.13), p < 0.001). Asphyxiated infants with signs of myocardial damage were associated with significantly higher cTnT than those without, 0.20 (0.11,0.28) and 0.11 (0.05,0.14 ug/L), p = 0.04. Conclusion: Cardiac troponin may prove to be valuable in evaluating myocardial damage in birth asphyxia. However, the degree of prematurity may complicate the assessment. [source] | ||||||||||