Objective To explore the correlation between liver volume variation of posthepatitic cirrhosis patients and the severity of the disease. Methods One hundred and eleven patients with normal livers and 74 posthepatitic cirrhosis patients underwent volume CT scan. The relation between normal liver volume and body height, body weight and body surface area was studied by linear regression and correlation method, the standard liver volume equation was deduced. The change ratio of liver volume in cirrhotic patients was calculated and compared with Child classification. Results The mean normal liver volume of Chinese adults was （1 225.15±216.23） cm3, there was a positive correlation between liver volume and body height, body weight 〔liver volume (cm3)=12.712×body weight (kg)+450.44〕 and body surface area 〔liver volume (cm3)=876.02×body surface area (m2)-297.17〕. The mean liver volume of Child A, B and C patients were （1 077.77±347.01） cm3, (1 016.35±348.60) cm3 and (805.73±208.85) cm3 respectively. The liver volume and liver volume index was significantly smaller in Child C patients than those in Child A and B patients (P＜0.05); while liver volume change ratio was higher in Child C patients (P＜0.05). Conclusion Liver volume variation of cirrhotic patients can be quantitatively assessed by 16 slices helical CT volume measurement and standard liver volume equation. The change of the liver volume is correlated with the severity of liver cirrhosis.
Objective To investigate the therapeutic effects of biphasic positive airway pressure (Bilevel) ventilation and volume ventilation plus [VV+，including volume control plus (VC+) and volume support (VS)] on respiratory failure in patients with chronic obstructive pulmonary disease (COPD).Methods 63 patients with COPD complicated by acute respiratory failure were intubated and underwent mechanical ventilation for at least 24 hours.At the first patients were underwent assist-control (A/C) ventilation for 2 to 4 hours to obtain the suitable basic ventilatory parameters.Meanwhile，the hemodynamics and oxygen dynamic parameters were measured.Then the patients were randomly allocated to three groups with 21 patients in each group and the ventilation mode was switched to Bilevel，VC+ and A/C mode correspondingly.The setting parameter was identical in three modes.In the process of weaning，patients in Bilevel group were ventilated with Bilevel and pressure support ventilation (PSV) mode at each pressure level，and subdivided into Bilevel and PSV 1 group accordingly.In VC+ group，the mode was switched to VS and PSV mode and subdivided into VC+ group and PSV 2 group,respectively.Every mode was run for 30 minutes while the ventilation function，blood gas exchange and lung mechanics index were measured.Results In the initial stage，the airway peak pressure (PIP) of Bilevel and VC+ mode obviously decreased，and the respiratory compliance was higher compared to the A/C mode. The effectiveness of Bilevel and A/C was equivalent in improving alveolar ventilation and oxygenation.The difference in the change of circulation function and blood gas between the two groups were not significant (Pgt;0.05).In the process of weaning，the effectiveness of Bilevel and VV+ was equal to PSV.The changes of breathing mode and blood gas between the two groups had no significant differences.Conclusions Bilevel and VV+ mode ventilation can be used in the whole mechanical ventilation for acute respiratory failure due to COPD with lower PIP，higher respiratory compliance compared to A/C model and similar performance as PSV during mechanical ventilation withdrawn.
Objective To compare the differences of flow and volume responses in patients with mild to very severe chronic obstructive pulmonary disease（COPD） in bronchodilatation test. Methods The different changes of FEV1 and FVC in 217 patients with mild to very severe COPD（GOLD stage Ⅱ-Ⅳ） after inhaling salbutamol were analyzed retrospectively. Results FEV1 and FVC of the patients with COPD at stage Ⅱ-Ⅳ increased remarkably after inhaling β2 agonist，while there were significant differences between the changes of FEV1 and FVC. Increment of FEV1 and FVC (ΔFEV1 and ΔFVC)，representing flow and volume responses respectively，showed a normal distribution. The majority of patients fell in the range of ΔFEV1 from 0.00 to 0.04，0.05 to 0.09 and 0.10 to 0.14 liter，and ΔFVC from 0.00 to 0.09，0.10 to 0.19 and 0.20 to 0.29 liter. There was significant difference of ΔFEV1 among stage Ⅱ-Ⅳ patients with COPD （Plt;0.01），namely more severe the disease less ΔFEV1 got.In the other hand ΔFVC increased along with the progression of COPD，although no significant difference of ΔFVC among stage Ⅱ-Ⅳ patients with COPD was found. Though different changes of ΔFEV1 and ΔFVC were revealed，there was a positive correlation between ΔFEV1 and ΔFVC in patients at each GOLD stage and the correlation became more insignificant with the progression of COPD. Conclusions There are significant differences between post-bronchodilator flow and volume responses in patients with COPD.Flow response decreases remarkably along with the progression of COPD，whereas volume response increases along with the progression of COPD.
Objective To evaluate the influence of tidal volume on the accuracy of stroke volume variation ( SVV) to predict volume state of pigs with ventilation.Methods Thirty-six healthy pigs were anesthetized after tracheal intubation and ventilated. With the envelope method, they were randomized into a normovolemia group, a hemaerrhagic shock group, and a hypervolemia group, with 12 pigs in each group. The pigs in the hemaerrhagic shock group were removed 20 percent of blood, and the pigs in the hypervolemia group received additional infusion of 20 percent 6% hydroxyethyl starch. In each group, ventilator settings were changed in a randomized order by changing VT [ VT = 5 mL/kg ( VT5 ) , VT =10 mL/kg ( VT10 ) , and VT =15 mL/kg ( VT15 ) ] . Hemodynamic measurements [ heart rate ( HR) , mean arterial boold pressure ( MAP) , systemic vascular resistance index ( SVRI) , cardiac index ( CI) , stroke volume index ( SVI) , intrathoracic blood volume index( ITBVI) , and SVV] were obtained after 10 minutes of stabilization. Results SVV was increased in the hemaerrhagic shock group comparing with the normovolemia group for VT10 [ ( 21 ±5) % vs. ( 11 ±2) % , P lt;0. 05] , but SVV was decreased in the hypervolemia group comparing with the normovolemia group [ ( 7 ±2) % vs. ( 11 ±2) % , P lt; 0. 05] . The variation tendency for VT15 was the same with VT10 , moreover SVV were all above 12% for the hemaerrhagic shock group, the normovolemia group, and the hypervolemia group [ ( 30 ±7) % , ( 19 ±3) % , and ( 15 ±4) % ] . There were no significant diffrences among the hemaerrhagic shock group, hypervolemia group and normovolemia group [ ( 8 ±6) % ,( 7 ±5) % , and ( 7 ±4) % , P gt; 0. 05] for VT5 . Conclusions SVV was a precise indicator of cardiac preload, but SVV was less sensitive to the changes of volume during low tidal volume ( 5 mL/kg) ventilation. The threshold of SVV for predicting fluid responsiveness maybe above 12% with a high tidal volume ( 15 mL/kg) ventilation.
Objective To investigate the effect of bilevel ventilation mode on blood gas and hemodynamics of patients with acute lung injury (ALI) by pulse indicator continuous cardiac output(PiCCO), and the clinical effect of this new ventilation mode on patients with ALI as well as its influence degree of circulatory system so that the cure rate of ALI can be improved. Methods There were 42 patients with ALI, 27 male and 15 female aged 15-75 years. According to the order of hospitalization, 40 patients (2 patients did not complete the study) were divided into two groups with 20 patients in each group. Bilevel ventilation group included the first 20 admitted patients. They were given bilevel ventilation support, using Support/Time(S/T) mode. The initial set of end inspiratory pressure (IPAP) was 8-10 cm H2O gradually increased to 14-20 cm H2O, which should be comfortable and appropriate for patients. The initial set of end expiratory pressure (EPAP) was 3-5 cm H2O gradually increased to 8-12 cm H2O. Fraction of inspired oxygen(FiO2) unchanged. Control group included the rest 20 admitted patients. They were given respiratory support, using Auxiliary/Control(A/C) mode followed by an increased positive endexpiratory pressure (PEEP) of 5 cm H2O,10 cm H2O,15 cm H2O,20 cm H2O. Each pressure kept 30 min. FiO2 unchanged. Indexes such as cardiac output (CO), systemic vascular resistance (SVR) etc were observed in both groups. Results There were 13 deaths in two groups, including 5 in bilevel ventilation group and 8 in control group. Seven cases died of multiple organ failure, 3 died of septic shock and 3 died of circulatory failure. Endotracheal intubation time (2.9±0.8 d vs. 4.2±0.9 d, t=7.737, P=0.006) and hospital stay (17.2±4.5 d vs. 18.5±3.6 d, t=2.558, P=0.039) in bilevel ventilation group were significantly shorter than those in control group. In control group, when PEEP ranged from 5 cm H2O to 15 cm H2O, arterial partial pressure of oxygen (PaO2) and oxygenation index (PaO2/FiO2) gradually increased as PEEP increased (Plt;0.05); when PEEP increased to 20 cm H2O, CO decreased, SVR, pulmonary vascular resistance (PVR) and airway peak pressure (PIP) increased than those in range of 515 cm H2O (Plt;0.05). In bilevel ventilation group, PaO2 and PaO2/FiO2 gradually increased as EPAP increased. When EPAP increased to 10 cm H2O, PaO2 and PaO2/FiO2 increased to the maximum (Plt;0.05); PIP was significantly lower than that in control group (t=7.831, .P.=.0.000). Conclusion Giving bilevel ventilation treatment to patients with ALI/acute respiratory distress syndrome(ARDS) can reduce the effects on respiratory and hemodynamic. PIP and the time of endotracheal intubation and hospital stay can be reduced without affecting hemodynamics.
Objective To investigate the dynamic changes of postoperative liver reserve function and laboratory liver function as well as liver volume regeneration, and their potential relationship with short-term clinical outcomes after adult-to-adult living donor liver transplantation (LDLT). Methods The data of 30 recipients underwent LDLT were prospectively collected. The plasma clearance (K) by indocyanine green (ICG) excretive test, liver function test by laboratory methods, liver volume by CT and shortterm (lt;3 months) complications were analyzed. Results The graft recipient body weight ratio (GRBW) was 0.63%-1.43%. The hepatic volume of the recipients in the operation was (638±103) ml, which was smaller than that day 7, 30, and 90 after operation (Plt;0.001), but the hepatic volume at subsequent time point was not different from that at the former time point (Pgt;0.05). The KICG values of recipients among the day 3 〔(0.177±0.056)/min〕, 7 〔(0.183±0.061)/min〕, 30 〔(0.200±0.049)/min〕, and 90 〔(0.209±0.050)/min〕 after operation gradually increased, which was respectively higher than that of recipients before operation (P=0.006, P=0.002, Plt;0.001, and Plt;0.001). Compared with the baseline KICG 〔(0.228±0.036)/min〕 of the donors, the KICG of recipients showed significant variation on day 3 and 7 after operation (P=0.004 and P=0.015), and the KICG of recipients on day 30 and 90 after operation approached the baseline KICG (P=0.355 and P=0.915). The recipients were divided into good liver function group (n=23) and poor liver function group (n=7) according to total serum bilirubin on day 14 after operation. The KICG significantly dropped compared with the recipients of good liver function group on day 3 after operation (P=0.001). Conclusions The liver volume regenerates dramatically on day 7 after operation for the recipients. The ICG excretivetest shows that volume recovery occurs much more gradually than the recovery of function in the recipients. The ICG excretive test is a more reliable indicator of graft function and subsequent graft outcome early after LDLT.
ObjectiveTo compare the dosimetric differences among the double-arc volumetric-modulated arc therapy (VMAT), 7 field intensity-modulated radiotherapy (IMRT) and 3-dimensional conformal radiotherapy (3D-CRT) techniques in treatment planning for cervical cancer as adjuvant radiotherapy. MethodFifteen patients who underwent adjuvant chemotherapy for cervical cancer between March 1st and September 30th, 2013 were chosen to be our study subjects through random sampling. Under Pinnacle 9.2 planning system, the same CT image was designed through three different techniques:VMAT, IMRT and 3D-CRT. We then compared target zone fitness index, evenness index, D98%, D2%, D50% among those different techniques. Monitor unit (MU) and treatment time were also analyzed. ResultsThree techniques showed similar target dose coverage. The IMRT and VMAT plans achieved better target dose conformity, which reduced the V20 of the pelvic, the V50 of the rectum and bladder, as well as the V40/50 of the small intestine (P<0.05). The VMAT technique showed few dosimetric advantages over the IMRT technique. VMAT technique had the advantages of less MU (P>0.05) and shorter overall treatment time (P<0.01) compared with IMRT technique. ConclusionsThe IMRT and VMAT plans achieve similar dose distribution to the target, and are superior to the 3D-CRT plans, in adjuvant radiotherapy for cervical cancer. VMAT technique has the advantages of less MU and shorter overall treatment time.
ObjectiveCompare the two-degrade collimator (MLC) angle selection's impact on plan quality and operational efficiency for volumetric intensity-modulated radiotherapy (VMAT) in the treatment planning system, and to explore the scheme for treatment plan optimization. MethodsTwenty patients with nasopharyngeal carcinoma underwent the treatment between March and December 2013 were randomly selected and planned for SIBVMAT treatment with different parameters set in the range of 0-60°with 15°interval for collimator angles. Planned dose distribution to the target volumes, organs at risk, and monitor units were compared. ResultsAs the MLC angle increased, target conformal index and homogeneity index had a trend to became deteriorated. The optimal plans were 0°and 15°, while 45°and 60°plans gave poor protection for the organ at risk compare to other angle plans and the monitor units were significantly increased. ConclusionChange the MLC angle had visible impact on treatment plans,there was a trend to deteriorate with the MLC angle increased, but small changes in MLC angle range can theoretically reduce the influence from leakage radiation on the human body.
ObjectiveTo discuss the application value of the two kinds of three dimensional reformatting techniques of spiral CT: volume rendering (VR) and maximum intensity projection (MIP) in the evaluation of children's skeletal abnormality. MethodsEighteen children with skeletal abnormality in our hospital treated between March and June 2014 were recruited in this study, diagnosed by CT transversal images and images of multiplanar reformatting (MPR). VR and MIP were made with the raw data. All three dimensional images were independently evaluated by two doctors of the Radiology Department (a score of 1-4). Images with a score of 4 were excellent. Wilcoxon signed ranks test was done for all scores and Kappa values were calculated. ResultsImages score of VR was 3.28±0.96 and of MIP was 2.89±0.90, without statistically significant difference (Z=-1.732, P=0.125). Kappa value of VR was 0.730 and of MIP was 0.593, with good and moderate consistency. ConclusionWith the special superiority of displaying spatial configuration, VR and MIP can be used to help two dimensional CT images to evaluate children's skeletal abnormality more comprehensively.
ObjectiveTo study the model to predict thymus volume with two-dimensional section diameters among fetuses. MethodsFrom September 2010 to March 2012, 210 singleton pregnant women suspected with fetal abnormality by prenatal ultrasonic testing were confirmed using MRI technology. Three two-dimensional section diameters of thymus were measured and the volume was calculated. No abnormal fetuses regarded as the standard, theoretical normal volume of fetal thymus was calculated. Paired t-test was used to compare the actual thymus volume with its corresponding theoretical normal value, and thus the fetuses were divided into two groups of normal and dysplasia so as to establish predictive model respectively. With two-dimensional section diameters as independent variables and thymus volume as dependent variable, the linear regression model was established. According to the model, the thymus volume was predicted and the error rate was calculated by formula: error rate=(predicted value-actual value) /actual value×100%. The Pearson correlation coefficient of error rate and fetal gestational age was calculated. ResultsThe models of normal and dysplasia groups to predict thymus volume were lnV=0.016d1+0.030d2+0.086d3+5.707+ε (R2=0.510) and lnV=0.048d1+0.036d2+0.016d3+6.011+ε (R2=0.447). The average absolute values of predicted error rate were 4.34% and 5.34% and decreased with fetal gestational age (normal r=-0.264, P=0.007; dysplasia r=-0.182, P=0.060). ConclusionThe prediction effects of above models are not so good and the model accuracy increases with fetal gestational age. Normal fetuses' model of different gestational age should be established to predict thymus volume by conducting large sample size study in the future. The modeling approach has certain practicability and clinical value and can be applied in ultrasonic technique.