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Objective To compare the efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery.Methods Thirty ASA Ⅰ or Ⅱ children of both sexes,aged 12-36 months,weighing 9-15 kg,scheduled for laparoscopic surgery,were randomly divided into two groups (n =15 each):pressure-controlled ventilation group (group P) and volume-controlled ventilation group (group Ⅴ).After anesthesia was induced with propofol 2-4 mg/kg,vecuronium 0.1 mg/kg and fentanyl 2 μg/kg,the children received endotracheal intubation and mechanical ventilation.The maximum inspiratory pressure was adjusted to make the tidal volume (VT) achieve 12 ml/kg in group P and the VT was set at 12 ml/kg in group V.The end-tidal pressure of carbon dioxide (PET CO2) was controlled at 35-45 mm Hg.The mean arterial blood pressure (MAP),heart rate (HR),arterial carbpn dioxide tension (PaCO2),PETCO2,minute ventilation and peak airway pressure were recorded immediately after intubation (T0),immediately before skin incision (T1),after 30 minutes of pneumoperitoneum (T2) and 15 minutes after the end of pneumoperitoneum (T3).Arterial blood samples were taken at the same time points mentioned above for blood gas analysis.Dynamic lung compliance and the ratio of the physiological dead space to the tidal volume were calculated.Results Compared with group Ⅴ,PaCO2 and PET CO2 were significantly decreased and dynamic lung compliance was significantly increased at T1-2,and minute ventilation and peak airway pressure were significantly decreased at T0-3 in group P (P ＜ 0.01).There was no significant difference in MAP,HR and the ratio of the physiological dead space to the tidal volume between the two groups (P ＞ 0.05).Conclusion Compared with volume-controlled ventilation,pressure-controlled ventilation can better improve the ventilatory efficacy,is more beneficial to gas exchange and reduces the influence of pneumoperitoneum on respiratory function in children undergoing laparoscopic surgery.
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Objective To compare the efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery. Methods Thirty ASA Ⅰ or Ⅱ children of both sexes,aged 12-36 months, weighing 9-15 kg, scheduled for laparoscopic surgery, were randomly divided into 2 groups (n = 15 each): pressure-controlled ventilation group (group P) and volume-controlled ventilation group (group V) . Anesthesia was induced with propofol 2-4 mg/kg, vecuronium 0.1 mg/kg and fentanyl 2 μg/kg. The children were tracheal intubated and mechanically ventilated. The maximum inspiratory pressure was adjusted to make the tidal volume (VT ) achieve 12 ml/kg in group P and the VT was set at 12 ml/kg in group V. PETCO2 was maintained at 35-45 mm Hg. MAP, HR, PETCO2 , minute ventilation and peak airway pressure were recorded immediately after intubation (T0 ) , immediately before skin incision (T1 ) , 30 min of pneumoperitoneum (T2 ) and 15 min after the end of pneumoperitoneum (T3 ) . Arterial blood samples were taken at the same time points mentioned above for blood gas analysis. Dynamic lung compliance and physiological dead space to tidal volume ratio were calculated.Results Compared with group V, PaCO2 and PETCO2 were significantly decreased and dynamic lung compliance was significantly increased at T1,2 , and minute ventilation and peak airway pressure were significantly decreased at T0-3 in group P ( P < 0.01) . There was no significant difference in MAP, HR and physiological dead space to tidal volume ratio between the two groups ( P > 0.05) . Conclusion Compared with volume-controlled ventilation, pressure-controlled ventilation can better improve the ventilatory efficacy, is more beneficial to gas exchange and reduces the influence of pneumoperitoneum on respiratory function in children undergoing laparoscopic surgery.
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Objective To investigate the relationship between hemodynamic changes in cervical and retrobulbar vessels and asymmetric diabetic retinopathy.Methods Color Doppler imaging(CDI) was used to quantitate diameter(D),peak systolic velocity(PSV),end diastolic velocity(EDV) and resistance index of the common carotid artery(CCA),the internal carotid artery(ICA),the ophthalmic artery(OA) and the central retinal artery(CRA),to quantitate diameter,velocity of central retinal vein(CRV),and to check carotid atherosclerosis in 12 patients with asymmetric diabetic retinopathy.Results The detection-rate of CCA and ICA atherosclerosis plaques was significantly increased in backgroud DR(41.7%)compared with that in proliferation DR(66.7%).There was a significant decrease in both PSV and EDV in OA in background diabetic retinopathy(BDR)(20.02±5.32 cm/s,5.26±2.15 cm/s) compared with PDR(27.23±12.20 cm/s,6.23±2.67 cm/s,P<0.05).There was a significant decrease in both PSV and EDV in CRA in BDR(6.44±1.78 cm/s,2.03±1.49 cm/s) compared with PDR(8.41±2.05 cm/s,2.66±0.67 cm/s,P<0.01).Conclusion The imbalance of perfusion in two eyes in diabetic patients might be one of the causes resulting in the asymmetric diabetic retinopathy