Monitoring lung impedance changes during long-term ventilator-induced lung injury ventilation using electrical impedance tomography.

OBJECTIVE: The target of this methodological evaluation was the feasibility of long-term monitoring of changes in lung conditions by time-difference electrical impedance tomography (tdEIT). In contrast to ventilation monitoring by tdEIT, the monitoring of end-expiratory (EELIC) or end-inspiratory (EILIC) lung impedance change always requires a reference measurement. APPROACH: To determine the stability of the used Pulmovista 500® EIT system, as a prerequisite it was initially secured on a resistive phantom for 50 h. By comparing the slopes of EELIC for the whole lung area up to 48 h from 36 pigs ventilated at six positive end-expiratory pressure (PEEP) levels from 0 to 18 cmH2O we found a good agreement (range of r 2 = 0.93-1.0) between absolute EIT (aEIT) and tdEIT values. This justified the usage of tdEIT with its superior local resolution compared to aEIT for long-term determination of EELIC. MAIN RESULTS: The EELIC was between -0.07 Ωm day-1 at PEEP 4 and -1.04 Ωm day-1 at PEEP 18 cmH2O. The complex local time pattern for EELIC was roughly quantified by the new parameter, centre of end-expiratory change (CoEEC), in equivalence to the established centre of ventilation (CoV). The ventrally located mean of the CoV was fairly constant in the range of 42%-46% of thorax diameter; however, on the contrary, the CoEEC shifted from about 40% to about 75% in the dorsal direction for PEEP levels of 14 and 18 cmH2O. SIGNIFICANCE: The observed shifts started earlier for higher PEEP levels. Changes of EELI could be precisely monitored over a period of 48 h by tdEIT on pigs.

Comparative analysis of perinatal outcomes among different typesof deliveries in term pregnancies in a reference maternity of Southeast Brazil.

OBJECTIVE: To compare the perinatal outcomes of women undergoing an elective cesarean section (CS) with those who had an emergency CS during the labor. DESIGN: Retrospective cohort study. SETTING: Hospital Estadual Azevedo Lima (HEAL), Niteroi, Brazil. METHODS: We analysed elective CS, emergent CS and vaginal delivery as dependent variables and neonatal data (admission in intensive care unit) as independent variables. Using the Statement of Live Birth during a three-month period, all patients who had their children after 38 complete weeks of pregnancy were selected. χ2 test and Student t-tests were applied to compare the groups. RESULTS: When patients who had vaginal delivery were compared with those who had an elective CS, we observed 219 normal deliveries with 1.8% of hospitalizations in neonatal intensive care units (NICU), and 88 patients of elective CS with 2.3% of admissions in closed units (p = 0.401). We had a sample of 108 newborns delivered by CS during the labor with 8.3% rate of hospitalization in NICU versus 1.8% of 219 newborns delivered vaginally (p = 0.005). CONCLUSION: The worst perinatal outcomes occurred when emergency CS were performed.

The cross-sectional area of umbilical cord components in normal pregnancy.

OBJECTIVE: To determine the normal cross-sectional areas of the umbilical vein, umbilical artery, and Wharton jelly in healthy pregnancies, and correlate the obtained values with fetal anthropometric parameters. METHODS: A cross-sectional study was performed with 312 women between the 24th and 39th weeks of a normal pregnancy. The cross-sectional areas of umbilical cord vessels were measured at the junction of the cord and fetal abdomen, and the values were subtracted from the total cord cross-sectional area to assess the cross-sectional area of the Wharton jelly. The anthropometric parameters analyzed were biparietal diameter, head circumference, femur length, and estimated fetal weight, and the Spearman correlation was used to assess the correlation between the cross-sectional areas of umbilical cord components and fetal anthropometric parameters. A polynomial regression analysis was performed to identify the curves that best adjusted to mean and standard deviation according to gestational age. RESULTS: A statistically significant correlation was observed between the cross-sectional areas of cord components and fetal anthropometric parameters (P<0.001) as well as gestational age (P<0.001). CONCLUSIONS: Reference measurements of the cross-sectional areas of umbilical cord components are important tools in the assessment of fetal growth.

Venous-arterial Doppler ratios in the prediction of acidemia at birth in pregnancies with placental insufficiency.

OBJECTIVES: Investigate the prediction of birth acidemia in pregnancies with placental insufficiency using two newly created venous-arterial Doppler ratios: pulsatility index (PI) of the ductus venosus (DV) over PI of the middle cerebral artery (MCA) and PI of the DV over PI of the umbilical artery and establish cut-off values for this prediction. METHODS: This was a prospective cross-sectional study involving 47 patients with placental insufficiency managed in two Brazilian hospitals. All pregnancies were singleton, over 26 weeks of age and without structural or chromosome anomalies. A ROC curve was calculated for the venous-arterial ratios (independent variable) and acidemia (dependent variable). RESULTS: The DV/AU PI ratio was not a good predictor of acidemia at birth. The DV/MCA PI ratio was related to fetal acidemia (area under the ROC curve 0.785, p = 0.004). The cut-off value was 0.582, sensibility 66.7%, specificity 77.1% and accuracy 74.5%. CONCLUSIONS: The DV/MCA PI ratio is adequate for the diagnosis of acidemia at birth in pregnancies with placental insufficiency. The cut-off value was 0.582.

Gemeos thoracopagus. / Thoracopagus conjoined twins

A gemelidade imperfeita, conhecida pelos leigos como "Gemeos Siameses", e estimada entre 1/50.000 a 1/100.000 de nascimentos e, aproximadamente, 1/600 gemeos vivem. Embora o diagnostico seja frequentemente omitido ate por procedimentos laboratoriais, os gemeos imperfeitos sao, ocasionalmente, diagnosticados antes do nascimento com base nos criterios radiologicos, ultra-sonograficos e, ate mesmo, por fotografia. O objetivo deste trabalho e apresentar um tipo raro de Gemeos Siameses e discutir a historia, incidencia, embriogenese, etiologia, classificacao e modalidade de diagnostico