ObjectiveTo evaluate the effect of positive end-expiratory pressure (PEEP) on respiratory function and hemodynamics in acute lung injury (ALI) with intra-abdominal hypertension (IAH).
MethodsSix pigs were anesthetized and received mechanical ventilation (MV). Volume controlled ventilation was set with tidal volumn(VT) of 8 mL/kg,respiratory rate(RR) of 16 bpm,inspired oxygen concentration (FiO2) of 0.40,and PEEP of 5 cm H2O. ALI was induced by repeated lung lavage with diluted hydrochloric acid (pH<2.5) until PaO2/FiO2 declined to 150 mm Hg or less to established ALI model. Intra-abdominal hypertension was induced by an nitrogen inflator to reach intra-abdominal pressure of 20 mm Hg. Respiratory parameters and hemodynamics were continuously recorded at different PEEP levels(5,10,15,and 20 cm H2O). Every level was maintained for one hour.
ResultsPaO2/FiO2 in PEEP5,10,15 and 20 were 90±11,102±10,172±23 and 200±34 mm Hg respectively. PaO2/FiO2 in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). Chest wall compliance (Ccw) in PEEP5,15 and 20 were 26±3,76±15 and 85±14 mL/cm H2O respectively. Ccw in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in lung compliance (CL) in different PEEP levels (P>0.05). Plateau pressure(Pplat) in PEEP5,10,15 and 20 were 30±3,31±2,36±2 and 38±4 cm H2O respectively. Pplat in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). There was no significant difference in Pplat between PEEP15 and 20 (P>0.05). Heart rate (HR) in PEEP5,15 and 20 were 113±17,147±30,and 160±30 beat/min respectively. HR in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in HR between PEEP15 and 20 (P>0.05).Cardiac index (CI) in PEEP5 and 20 were 4.5±0.6 and 3.5±0.6 L·min-1·m-2 respectively. CI in PEEP20 was significantly lower than that in PEEP5 (P<0.05). There was no significant difference in CI in PEEP5,10 or 15(P>0.05). Central venous pressure(CVP) in PEEP5,15 and 20 were 12±2,17±2,and 18±3 mm Hg respectively. CVP in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in CVP between PEEP15 and 20 (P>0.05). There were no significant differences in MAP,SVRI,ITBVI,GEDI,PVPI,or EVLWI between different PEEP levels.
ConclusionConcomitant ALI and IAH can induce great impairments in respiratory physiology. When PEEP is gradually increased,oxygenation and the respiratory function are improved without significant secondary hemodynamic disturbances.
Objective To analyze the effect of monitoring and modulating the portal vein pressure and blood flow during living donor liver transplantation （LDLT） on preventing small-for-size-syndrome (SFSS). Methods Data of forty-four LDLT recipients between Oct.2007 and Oct.2008 were reviewed. Actual graft-to-recipient weight ratio（GRWR）, portal vein flow and pressure during operation and syndrome of SFSS after operation were recorded. The patients received splenectomy or splenic artery ligation according to actual GRWR, portal vein flow and pressure and WBC. Relationships between patients’ GRWR, portal vein flow, portal vein pressure and occurrence of SFSS were analyzed. Results Six patients received splenectomy and 7 patients received splenic artery ligation to decrease the portal vein flow and pressure during the operation. The portal vein flow and pressure decreased after splenectomy （Plt;0.05）. The portal vein pressure decreased （Plt;0.05） and the portal vein flow had no significant change after splenic artery ligation （P＞0.05）. No SFSS occurred after operation. Conclusion Modulation of portal vein flow and pressure by splenectomy or splenic artery ligation during LDLT operation can decrease the portal vein flow and pressure, and which can prevent the incidence of SFSS.
Objective
To investigate the effect of prone position ventilation (PPV) on hemodynamics in patients with interstitial lung disease (ILD) concurrent with acute respiratory distress syndrome (ARDS) or not.
Methods
Severe ARDS patients received PPV treatment in intensive care unit from 2013 to 2015 were retrospectively analyzed. Pulse index continuous cardiac output (PiCCO) monitoring indices were compared 2h before PPV (PPV-2), in-PPV (PPVmean) and 2h after turn back to supine position (PPV+2), including mean arterial pressure (MAP), cardiac index (CI), intrathoracic blood volume index (ITBVI), etc. Heart function, liver function, renal function, coagulative function were compared before and after all the PPV treatment.
Results
Thirty-six severe pulmonary ARDS patients were recruited. Norepinephrine (NE) dose was (0.14±0.10) μg·kg-1·min-1 and lactate concentration was (1.70±0.57) mmol/L before PPV. CI in all the patients was increased [(4.06±0.95) L·min-1·m-2 vs. (3.98±1.05) L·min-1·m-2, P > 0.05) and central venous oxygen saturation, ITBVI [(76.94±8.94)% vs. (70.67±8.23)%, (982.17±245.87) mL/m2 vs. (912.97±177.65) mL/m2, P < 0.05)] were significantly increased compared with PPV-2, while heart rate (HR), MAP, urine volume were decreased (P > 0.05). The patients were divided into an ILD group (n=17) andanon-ILD group (n=19),and no significant differences were found in baseline data between two groups. Compared with PPV-2, MAP was significant decreased at PPV+2 [(85.44±10.84) mm Hg vs. (89.21±10.92) mm Hg, P < 0.05) in the ILD group. Compared with PPVmean, CI was obviously declined at PPV+2 in the ILD group. Activated partial thromboplastin time was increased [(67.04±97.52)s vs. (41.24±8.72) s, P < 0.05] and BUN was higher [(10.64±4.95) μmol/L vs. (8.18±3.88) μmol/L, P < 0.05] in the ILD group, while no significant difference was found in the non-ILD group.
Conclusion
PPV will not affect cardiac output in severe ARDS patients with ILD. It can increase venous return and improve tissue perfusion, but the perfusion of the abdomen organ need to be monitored cautiously.
Objective To study the influence of the pedicle length on the perforator flaps in hemodynamics. Methods Four mature swine (2 males, 2 females; weight, 23.0±2.0 kg) were applied to the experiment.Two transverse abdominal skin flaps, based on the superior epigastric pedicle orits rectus abdominal muscle perforators, were designed; each swine was used as its own control. At 2 hours and 1, 2, 3 weeks postoperatively, the skin paddle perfusion and the blood stream velocity in the superior epigastric artery were measured by the Laser Doppler Flowmeter and the Color Doppler Ultrasound, respectively. Flap survival percentages were calculated by the grid method at 1 week postoperatively. The swine were euthanatized, and they underwent angiography at 3 weeks postoperatively. Results At 2 hours and 1 week after operation, edema of the perforator flaps with the superior epigastric pedicle was more severe than that of the skin flaps with the rectus abdominal muscle perforator, and the skin perfusion had a statistical difference between the two kindsof flaps (Plt;0.05). The skin paddle viability and the skin perfusion had nostatistical difference after the first week postoperatively (Pgt;0.05). At 2hours and 1 week after operation, the blood stream velocity in the superior epigastric artery in the perforator flap with the superior abdominal artery pediclewas reduced, and there was a statistical difference between the two kinds of flaps (Plt;0.05); however, the velocity was almost the same after the first week postoperatively. Conclusion The excessively long pedicle of the perforator skin flap may have an unfavorable influence on the flap perfusion,especially during the first week after operation, because of the vascular compromise during the dissection of the long pedicle. The blood vessel anastomosis atthis level of the blood vessels may have no relationship with the perforator flap in hemodynamics. This study can also indicate that the ligation of the branches in the recipient vessels cannot make the perforator flaps overperfused.
The effcet of topical timolol maleate 0.5% on the coroidal circulation was investigaed in 22 normal subjects using the color Doppler,with one eyes as the timolo-treated eye and the contralateral eye as the auto-control eye in each individual.The result showed that,of the 2 groups of eyes,there was a sighificant increase in time average maximum velocity(TAMX),systolic peak velocity(Vs),and distolic velocity(Vd) in timolol-treated eyes.The resistance index in timolol-treated eyes was lower than in the control eyes(p＜0.05). Significant linear correlation in the timolol-treated eyesfound between perfusion and TAMX.It is thought that the increase in volumetric blood flow rate by timolol is due to two concurrent processes:1.an indrect effect on the choroidal circulation through the increase in perfusion pressure; 2.a dirct effect on choroidal vessels resulting from action of drug on adrenergic receptors that is present in the choroidal vasculature.
（Chin J Ocul Fundus Dis,1996,12: 83- 85）
ObjectiveTo investigate impact of splenectomy plus pericardial devascularization on liver hemodynamics and liver function for liver cirrhosis patients with portal hypertension.
MethodsThe internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of portal vein and hepatic artery of 42 cases of liver cirrhosis with portal hypertension were measured by Doppler ultrasonic instrument on day 1 before operation and on day 7 after operation. The free portal pressures at different phases (after open abdomen, after splenic artery ligation, after splenectomy, and after devasculanrization) were read from the disposable pressure sensor. Twenty-four healthy people through physical examination were selected as control.
Results① The free portal pressure of liver cirrhosis patients with portal hypertension was decreased from (29.12±1.40) mm Hg after open abdomen to (22.71±1.21) mm Hg after splenic artery ligation, and further decreased to (21.32±1.12) mm Hg after splenectomy, but increased to (22.42±1.15) mm Hg after devasculanrization, the difference was statisticly different (all P < 0.01). ② Compared with the healthy people, for the liver cirrhosis patients with portal hypertension, the internal diameter, maximum velocity, minimum velocity, and flow volume of portal vein were significantly enlarged (all P < 0.01), which of hepatic artery were significantly reduced (all P < 0.01) on day 1 before operation; On day 7 after operation, the internal diameter of portal vein was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, and mean velocity of portal vein were significantly enlarged (all P < 0.01), but the internal diameter of hepatic artery was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01). For the liver cirrhosis patients with portal hypertension, compared with the values on day 1 before operation, the internal diameter and the flow volume of portal vein were significantly reduced (all P < 0.01) on day 7 after operation; the internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01) on day 7 after operation. ③ The Child-Pugh classification of liver function between before and after surgery had no significant difference (χ2=1.050, P > 0.05). ④ No death and no hepatic encephalopathy occurred, no thrombosis of splenic vein or portal vein was observed on day 7 after surgery.
Conclusionsplenectomy plus pericardial devascularization could decrease portal vein pressure and reduce blood flow of portal vein, while increase blood flow of hepatic artery, it doesn't affect liver function.
ObjectiveTo explore the effects of metoprolol on hemodynamics of early septic shock patients with myocardial injury.
MethodsWe prospectively recruited 22 septic shock patients with myocardial injury, who were admitted to the ICU of Xiaolan Hospital during March 2014 and February 2015.The metoprolol was injected through central venous catheter to reduce heart rate by 20% from baseline and maintain for 6h.Hemodynamic and oxygen metabolic parameters were collected to establish database.
ResultsHeart rate decreased significantly to (98±18), (95±16) and (92±18) beat/min respectively at 1h, 3h and 6h post-dosing, compared with (125±28) beat/min at pre-dosing (P < 0.05).Cardiac index decreased significantly to (3.2±1.5), (3.3±1.9) and (3.3±1.6) L·min-1·m-2 respectively at 1h, 3h and 6h post-dosing, compared with (3.9±2.5) L·min-1·m-2 at pre-dosing (P < 0.05).The mean blood pressure, central venous pressure, pulmonary artery wedge pressure, pulmonary vascular resistance index, systemic vascular resistance index and stroke volume index showed no significant changes between pre-dosing and post-dosing (all P > 0.05). Lactate concentration decreased significantly to (9.8±4.1) and (8.1±3.6)mmol/L respectively at 3h and 6h post-dosing, compared with (13.4±5.2)mmol/L at pre-dosing (all P < 0.05), but mixed venous oxygen saturation showed no significant changes (P > 0.05).
ConclusionMetoprolol may reduce heart rate and cardiac output in septic shock patients with myocardial injury, without obvious adverse effects on circulatory function and systemic perfusion.
This study was performed on canine femoral veins which were interpositionally implanted into the femoral arteries and the investigation was in terms of zero-stress state, compliance and hemodynamic assessment. The results revealed that the vein grafts had the similar characteristics of compliance with the normal veins. Using Doppler ultrasonography to monitor the blood flow velocity through the vein grafts, the hemodynamic parameters such as pulsatility index (PI) and blood flow volume were evaluated consecutively within one month after the operations .No significant differences were found between these parameters at different time points. It was suggested that autogenous vein graft had an adaptive course when operating in an arterial hemodynamic circumstances and It’s mechanical changes did not bear upon the hemodynamics through the vein graft.
ObjectiveTo compare the anesthetic potency and influence on maternal hemodynamics among spinal anesthesia (SA), epidural anesthesia (EA) and combined spinal epidural anesthesia (CSEA) for women undergoing cesarean sections.
MethodsA total of 180 singleton term nulliparous pregnancies of American Sociaty of Anethesiologists physical status Ⅰor Ⅱ for cesarean sections in Guangyuan Central Hospital from January to December 2012 were allocated into three groups using the method of random number table. Patients in group SA received SA (n=60), group EA underwent EA (n=60) and patients in group CSEA accepted CSEA (n=60). Patients wderwent punere all placed in left lateral position. Group EA patients unctures at the L1-2 interspace and the volume of carbonated lidocaine used initially was 12-15 mL. Group SA and CSEA accepted the anesthesia at either L2-3 or L3-4 interspace. The volume for group SA was 0.75% bupivacaine 1.2 mL with 10% glucose solution 1 mL, and for group CSEA was 0.5% bupivacaine 1.4 mL with 10% glucose solution 0.8 mL. A catheter was inserted into the epidural space for 3-4 cm after spinal needle exit so as to add additional epidural medication according to the block level and the level of anesthesia subsidence. The values of the basis of blood pressure and heart rate, the lowest blood pressure and heart rate, umbilical venous blood gas, start effect and induction time of anesthesia and the highest block level of anesthesia were record.
ResultsThere were statistically significant differences in terms of start effect time of anesthesia among the three groups (F=24.642, P<0.001). The start effect time of anesthesia in group SA and CSEA was significantly shorter than that in group EA (t=8.076, 7.996; P<0.05). The induction time of anesthesia in group SA was significantly shorter than those in group EA and CSEA (P<0.05). The lowest blood pressure and heart rate in group SA and CSEA were significantly lower than the values of basis (P<0.05). The lowest blood pressure and heart rate in group SA was significantly lower than that in group EA (P<0.05). The incidence of hypotension and bradycardia in group SA and CSEA was significantly higher than that in group EA (P<0.05). The block level of anesthesia in the three groups were at thoracic 8.12±1.22, 8.36±1.88 and 8.52±1.92 respectively, and there was no significant difference among the three groups (F=0.081, P=0.923).
ConclusionEA and CSEA surpass SA in the choice of neuraxial anesthesia for cesarean sections, and 1.73% carbonated lidocaine for EA can improve anesthetic potency and better maintain relatively stable hemodynamic indexes.
PURPOSE:To investigate the relationship between the development of the diabetic retinopathy(DR)and the changes of ocular hemodynamics. METHODS:The hemodynamic parameters (Vmax,Vmin,RI)of central relinal artery(CRA )and central retinal vein(CRV)were measured both in the diabetes mellitus(DM) group(72 cases)and the control group(28 cases)with color Doppler flow imaging(Acuson-128XP/10). RESULT:The hemodynamic changes in CRA and CRV in the different stages of DR had their own characteristicS. The blood flow in CRA of the DM patients without DR was higher than that of the control (Plt;0.05). With tile deterioration of the retinopathy the blood flow in CRA decreased. The velocity of the
blood flow in CRA of the proliferative DR group was less than that in the control ,DM without DR patients and background DR patients(Plt;0.05). The velocity of the flow in CRV of the DM patients was higher than that of control (Plt;0.001 )and exhibited its remarkable pulsative pattern. CONCLUSIONS:The changes of the hemodynamics in CRA.CRV was associated
with the development of the diabetic retinopathy. （Chin J Ocul Fundus Dis,1997,13: 210-212 ）
