ABSTRACT
Objective:To evaluate the diagnostic and predictive value of ultrasonic cardiac output monitor (USCOM) in premature infants with hemodynamic significant patent ductus arteriosus (hsPDA).Methods:A total of 165 preterm infants with gestational age less than 34 weeks and within 72 hours after birth in the Neonatal Medical Center of Children′s Hospital of Nanjing Medical University from January 2018 to June 2020 were retrospectively analyzed.According to the echocardiograph (ECHO) results within 72 hours after birth, clinical manifestations and oral administration of Ibuprofen, premature infants were divided into non-patent ductus arteriosus (non-PDA group, 77 cases), non-hsPDA group (59 cases), and hsPDA group (29 cases). USCOM was performed within half of an hour after ECHO.During the course of oral medication of Ibuprofen in the hsPDA group, USCOM was repeatedly examined every 24 hours.ECHO and USCOM were re-examined within 24 hours after the course of oral medication of ibuprofen.Results:Compared with non-hsPDA group and non-PDA group, the gestational age [(31.51±1.62) weeks, (32.09±1.27) weeks vs.(30.82±1.61) weeks, F=8.425, P<0.001], birth weight [(1 154.49±192.55) g, (1 195.58±182.02) g vs.(1 094.66±153.69) g, F=3.366, P=0.037] and the mean blood pressure [(38.37±2.20) mmHg, (38.53±2.37) mmHg vs.(30.52±2.31) mmHg, 1 mmHg=0.133 kPa, F=142.860, P<0.001]were significantly lower in hsPDA group.On the contrary, the heart rate[(129.68±7.11) times/min, (130.34±7.27) times/min vs.(164.76±7.65) times/min, F=271.790, P<0.001], B-type natriuretic peptide[(203.76±108.68) ng/L, (152.43±54.24) ng/L vs.(3 385.31±856.26) ng/L, F=931.30, P<0.001] and left artrium/aorta (1.32±0.12, 1.29±0.09 vs.1.60±0.12, F=84.970, P<0.001)were significantly higher.Among the USCOM parameters, left ventricular cardiac output [(0.40±0.08) L/min, (0.40±0.08) L/min vs.(0.51±0.04) L/min, F=26.760, P<0.001], cardiac index (CI) [(3.76±0.48) L/(min·m 2), (3.54±0.30) L/(min·m 2) vs.(4.43±0.36) L/(min·m 2), F=56.060, P<0.001], stroke volume[(3.75±0.28) mL, (3.70±0.23) mL vs.(4.22±0.36)mL, F=40.170, P<0.001], stroke volume index [(34.42±2.66) mL/m 2, (34.47±3.29) mL/m 2vs.(38.45±3.32) mL/m 2, F=20.080, P<0.001], peak ejection velocity [(1.12±0.12) m/s, (1.11±0.10) m/s vs.(1.23±0.09) m/s, F=14.890, P<0.001] and corrected flow time [(379.02±22.69) ms, (376.51±27.95) ms vs.(403.69±39.04) ms, F=10.120, P<0.001]were significantly higher in hsPDA group, while systemic vascular resistance index (SVRI) [(1 109.49±115.67) ds·cm -5·m 2, (1 070.01±133.55) ds·cm -5·m 2vs.(861.31±115.22) ds cm -5m 2, F=41.130, P<0.001]was significantly lower than that of non-hsPDA and non-PDA group.The area under the receiver operating characteristic curve of CI and SVRI for predicting hsPDA were 0.916 and 0.905, respectively.The sensitivity and specificity of CI>4.05 L/(min·m 2) for predicting hsPDA was 0.828 and 0.860, respectively, which was 0.660 and 1.000 for SVRI<1 002.5 ds·cm -5·m 2.The sensitivity and specificity of combining CI and SVRI for predicting hsPDA was 0.966 and 0.949, respectively. Conclusions:USCOM has a good diagnostic and predictive value for hsPDA in premature infants.The combined application of CI and SVRI can improve the predictive value, and help formulate the early diagnostic and treatment strategy for PDA in premature infants
ABSTRACT
The effects of lorazepam on cerebral function, metabolism, and hemodynamics were studied in eight dogs receiving a general anesthesia with isoflurane(0.5 vo1%)-50% nitrous oxide-oxy-gen. The effects of benzodiazepine antaronist, flumazenil, were also examined. Lorazepam(0.5 mg/kg) administration did decrease mean arterial pressure(MAP) and herat rate(HR). It did significantly decrease cerebral blood flow(CBF)(measured by posterior sagittal sinus outflow method) by 25% of control value(68+/-l3 vs. 51+/-12ml/100gm/min, meanSD) and cereberal metabolic rate for oxygen(CMRO ) by 17% (3.96+/-1.04 vs. 3.30+/-0.92ml/l00gm/min, mean+/-SD). Electroencephalogram(EEG) converted to high amplitude, predominantly theta and delta activity. Intracranial pressure(ICP) increased markedly. Following flumazenil(0.06 mg/kg) administration, HR recovered completely to control level but MAP increased only at 5 min. compared to pre-flumazenil value and returned to pre-flumazenil level. CBF recovered to control level for 15 min. and deereased after 30 min. compared to control level but higher than pre-flumazenil level about 9-15%. CMRO recovered completely to control leveL EEG changed to an awake pattern after fluamzenil administration. It is concluded that lorarepam decreased cerebral function and metabolism and depressed hemodynamic fuction. Benzodiazepine antag- onist, flumazenil, was effective in reversing cerebral and hemodynamic effects, may be in dose related manner.