Early Transient Neonatal Cyanosis Related to Interatrial Right-to-Left Shunting at an Altitude of 1890 Meters: A Report of Five Cases

Background

We report five term neonates born at an altitude of 1890 meters with transient early neonatal cyanosis due to right-to-left shunting at atrial level through patent foramen ovale.

Case Presentation

The five neonates with no clinical sign or symptom other than marked cyanosis were examined in two neonatal units of Erzurum city. Hematologic and radiologic examinations were normal. Partial oxygen pressure (PO₂) in the arterial blood samples was lower than 45 mmHg in all of the patients, and did not increase more than 15 mmHg in any of the patients after inhalation of 100% oxygen. Echocardiography revealed normal intracardiac structure. The right-to-left interatrial shunt at diastole was detected through a patent foramen ovale in all of these infants. By only observation with no treatment, diastolic right-to-left shunt disappeared in 40.15±9.52 hours. Oxygen saturation was increased from 69.80±9.55 percent to 90.40±8.80 percent. The patients were discharged from the hospital at 5.6±0.4 days of life. Follow up for 6 months revealed no clinical problem in any of the cases.

Conclusion

Transient cyanosis can be seen in the very early neonatal period because of interatrial right-to-left shunting in some healthy term neonates born at an altitude of 1890 meters. Decreased right atrial compliance due to relative hypoxia at that altitude can be speculated to be the causative mechanism.     

Endothelial progenitor cells, bronchopulmonary dysplasia and other short-term outcomes of extremely preterm birth

Aim

To evaluate the impact of endothelial progenitor cells (EPCs), a subset of committed circulatory stem cells, on the development of bronchopulmonary dysplasia (BPD) and other short term outcomes in a cohort of extremely premature newborns.

Methods

Progenitor cells were quantified by flow cytometry at birth in 36 neonates born <=28 weeks of gestation and at 36 postmenstrual weeks in 18 of them. Cells expressing the stemness markers CD34, CD133, or both were defined as circulating progenitor cells (CPCs). EPCs were defined as CPCs co-expressing the endothelial marker KDR.

Results

Mean (SD) gestational age and birth weight of the infants studied were 26.2(1.5) weeks and 761.6(171.8) grams, respectively. EPC levels at birth did not differ between infants who subsequently developed BPD (n = 9) and those who did not (n = 24) [CD34⁺KDR⁺ EPCs: 81(34-41) vs 80(56-110), p = 0.7] and were not correlated with the duration of mechanical ventilation or O2-dependence, nor with the need of surfactant replacement. Infants with a hemodynamically significant patent ductus arteriosus (PDA) (n = 22) had significantly lower EPC levels at birth than those with no PDA (n = 11) [CD34⁺KDR⁺ cells: 47(34-92) vs 142(84.5-221), p = 0.008]. Data from the 18 infants studied both at birth and at 36 postmenstrual weeks showed that, while CPCs sharply decline over time, levels of all EPCs phenotypes are preserved after delivery.

Conclusions

Levels of EPCs at birth did not affect the risk of developing BPD in our group of extremely premature neonates. However, the association between low EPC counts at birth and PDA may be clinically relevant, and deserves further studies.     

Tomographic evaluation of the mandibular nerve in the mental region and its surgical implications: a cross-sectional study

The aim of this study was to evaluate the prevalence and length of the anterior loop (AL) of the inferior alveolar nerve, nerve emergence from the mental foramen, and prevalence of sensory disorders after implant placement in the interforaminal region. Four hundred and fifty hemimandibles (225 patients) were evaluated using cone beam computed tomography and panoramic radiographs. Information on the presence of sensory disorders was obtained from the medical records. AL prevalence was 13.6% and mean AL length was 1.25 mm. The false-negative rate for the identification of the AL using panoramic radiography was 58.6%. Straight nerve emergence from the mental foramen was the most prevalent (62.7%), followed by anterior (21.8%) and posterior (15.6%) emergence. The incidence of sensory disorders was 4.4%, and 1.1% were related to the presence of the AL. When implants were placed within the planned distance of the mental foramen or further, 1.2% had sensory problems associated with the presence of the mandibular incisive canal. In cases of distances smaller than planned, 12.9% had sensory alterations. Only five (1.1%) had the AL, with a length between 0 and 4.5 mm. However, in four cases, the planned distance was respected and, even so, there was a sensory disorder. Posterior nerve emergence from the mental foramen was associated with a higher prevalence of AL.     

介入造影定位法制作比格犬卵圆孔未闭模型

目的 介绍一种用于制作比格犬卵圆孔未闭(PFO)模型的介入造影定位穿刺方法.方法 15只健康比格犬通过介入造影定位法制作PFO模型.全身麻醉下穿刺右股静脉,在右前斜30°X线投照角度下,于上腔静脉边推对比剂边回撤导管至右房底部作造影,结合改良有心房造影穿刺(Inoue法)定位法作房间隔穿刺,用14F扩张鞘管扩张房间隔,制作犬PFO模型.结果 与犬房间隔穿刺相关生理与解剖:静息心率快,左右心房内径小,伴有奇静脉开放,下腔静脉在右心房开口位置高,下腔静脉长轴与其入右心房口处均有明显成角,且与房间隔平面成角大.15只比格犬右股静脉穿刺成功率为100％;14只犬房间隔穿刺成功,且均制成PFO模型,1只犬穿破心包放弃进一步操作,成功率为93.3％(14/15);PFO模型制成后即刻超声测量显示,PFO大小为2.5～4.1(3.2±0.7)mm.结论 介入造影定位法制作比格犬PFO模型,操作简便、安全,成功率高.     

成人胸椎间孔韧带的解剖学观测

目的 通过解剖观测成人胸椎间孔韧带.为国人提供胸椎间孔韧带的解剖学资料并探讨其临床意义.方法 选用成人尸体标本15具,解剖观察胸椎间孔韧带.用游标卡尺进行相关测量.结果 在30侧成人胸椎标本中未发现横孔上韧带和体横韧带.T1椎间孔内未发现横孔下韧带,T2～T12椎间孔内均发现横孔下韧带,其出现率从T2～T12呈逐渐增加...