ABSTRACT
Objective To evaluate the efficacy and safety of permissive hypercapnia ventilation in mechanically ventilated newborns.Methods PubMed,Embase,the Cochrane Library,China National Knowledge Infrastructure (CKNI),Wanfang Data and Chinese BioMedical Literature Database (CBM) were searched up until March 31,2013.Randomized controlled trials (RCTs) comparing permissive hypercapnia (PHC) group with normocapnia (NC) group in mechanically ventilated newborns were included.The primary outcomes included the incidence of ventilator associated lung injury (VALI),bronchopulmonary dysplasia (BPD),intraventricular hemorrhage (IVH),periventricular leukomalacia (PVL),patent ductus arteriosus (PDA),neonatal necrotizing enterocolitis (NEC),neurodevelopmental injury and the mortality rate.Secondary outcomes included the duration of ventilatory support and the length of hospital stay.The Cochrane Handbook 5.1.0 was used to evaluate the methodological quality and RevMan 5.1 software from Cochrane Collaboration was used for meta-analysis.The fixed effects model or the random effects model was adopted according to the result of heterogeneity.Results (1) A total of 325 articles were searched,and eight RCTs involving 605 newborns (302 newborns in PHC group while 300 newborns in NC group) which met the inclusion criteria were selected.In seven studies,the partial pressure of carbon dioxide (PCO2) was controlled at ＜ 65 mmHg (1 mmHg=0.133 kPa) and pH at ≥ 7.2 in PHC group.In one study,PCO2 was ＞ 52 mmHg and pH＞7.2,without descripition of the upper limit of PCO2.(2) Four articles described the method of random allocation in detail; three described allocation concealment; all eight studies used blinding method for research subjects; two used blinding method for outcome assessment; all eight studies reported complete data; and three articles described the source of other bias.(3) All eight studies reported the incidence of VALI (I2=56％,P=0.03).The random effects model was used for the meta-analysis,and there was significant difference between PHC group and NC group (RR=0.52,95％CI:0.29-0.93,P=0.03).According to the gestational age,the eight studies were divided into two subgroups.One subgroup,including three studies with an average gestational age of 25 weeks (I2=0％,P=0.46),showed no significant difference in the incidence of VALI between PHC and NC group (RR=1.05,95％CI:0.72-1.54,P=0.78).The other subgroup,including five studies with gestational age of ＞27 weeks (I2=0％,P=0.68),showed significant difference in the incidence of VALI between the two groups (RR=0.27,95％CI:0.14-0.50,P＜0.01).The in-hospital mortality and duration of ventilation showed significant difference between the two groups (in-hospital mortality:RR=0.40,95％CI:0.22-0.74,P＜0.01; duration of ventilation:difference in means=-0.75,95％CI:-1.04--0.46,P＜0.01).There was no significant difference in the incidence of BPD,IVH,PVL,PDA,NEC and neurodevelopmental impairment between the two groups (all P＞0.05).Conclusions PHC ventilation in mechanically ventilated newborns can decrease the incidence of VALI,the in-hospital mortality and the duration of ventilation,while its protective efficacy against BPD is not remarkable.It does not increase the risk of IVH,PVL,PDA,NEC and neurodevelopmental injury,when the PCO2 is ＜ 65 mmHg and pH ≥ 7.2.
ABSTRACT
BACKGROUND: Clinical evidence have proved that heterotopic ossification is easily present in bony callus of patients with fracture combined with head injury, and the healing of bone fracture is accelerated obviously. OBJECTIVE: To study the expression and distribution of vascular endothelial growth factor (VEGF) in bony callus among the patients with fracture combined with head injury and simple fracture patients, and to investigate its clinical significance and action mechanism.DESIGN, TIME AND SETTING: Grouping controlled observation was performed in the Xijing Hospital, the Fourth Military Medical University of Chinese PLA between February 2006 and July 2007.PARTICIPANTS: The patients comprised two groups those who had fracture combined with head injury and those who had simple fracture. Each group had 50 patients. The fracture combined head injury group included 41 males and 9 females, aged 19-55 years; simple fracture group included 36 males and 14 females, aged 17-52 years. METHODS: The bony callus specimens were harvested at 7-10, 11-15, 16-20, 21-27 and 28-35 days post-injury. The content of VEGF in bony callus was measured at different phase by using immunohistochemistry methods, and the speed of fracture healing was also observed.MAIN OUTCOME MEASURES: ①X-ray results; ②immunohistochemical image analysis. RESULTS: In different phase of bone healing, the VEGF of the two groups were homogenous, the early expression of VEGF in osteoprogenitor cell, osteoblast and cartilage cell in the fracture combined with head injury group was significantly higher than those in simple fracture group. The osteoprogenitor cell proliferated, and the differentiations of osteoblast and cartilage cell were enhanced obviously. The VEGF level reached the peak at 7-10 days, and kept at the high level for 30 days and then gradually decreased. The peak of VEGF level in simple fracture group came at 11-15 days, kept in the high level for 20 days and then gradually decreased. The peak value in simple fracture group was significantly lower than the fracture combined with head injury group. There was statistical significance in the expression of VEGF between two groups by the paired t-test (P < 0.05). A large mount of osteotylus could be detected at 4 weeks after injury by X-ray in patients with fracture combined, with head injury, but at 7-9 weeks in patients of those who had simple fracture.CONCLUSION: The expression of VEGF in the bony callus in the group of fracture combined with head injury is significantly greater than that in simple fracture patients, and the expression lasts for a longer time. The proliferation and differentiation of osteogenitor call, osteoblast and cartilage cell are also significantly faster in the group of fracture combined with head injury, which might be one of the bone healing mechanisms.
ABSTRACT
This paper introduces a simple ultrasound studio suited to both field battle and peace time, which has many advantages including slight weight, stable structure, easy to take and simple operation. The studio can be applied to all kinds of medical organization and can improve the diagnostic level of ultrasound in field battle and peace time.