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 hemodynamics changes of the common carotid arteries in 10 SD rats were measured with a color doppler flowmetry in an attempt to define the changes resulting from end-to-end anastomosis. The left common carotid arteries were divided and followed by end-to-end anastomosis. The systolic mean peak velocities in the left arteries were measured at the proximal, distal and anastomotic sites and in the right intact arteries as well at 6, 12, 24, 48, 72 and 120 hours after repair. The percentage of area reduction at anastomosis was calculated from these data. The results indicated that the systolic mean peak velocity at the anastomotic sites was significantly increased as compared to the velocity at the proximal, distal and contralateral sites (P lt; 0.05). The velocity at the distal sites was significantly lower than that from the proximal and contralateral sites (P lt; 0.05), the mean percentage of the reduction was 33.18% and 33.33%, respectively. From 6 hours to 120 hours after anastomosis of arteries there was various degree of narrowing at the site of anastomosis. The mean per cent of stenosis was 42.48%. It was concluded that from 6 to 120 hours after end-to-end anastomosis of the small arteries, the velocity at the anastomotic site was increased as compared to the velocities at pre- and post-anastomotic sites. The increase of velocity at the site of anatomosis was caused by stenosis at the anastomosis.
To explore the influence of bionic texture coronary stents on hemodynamics, a type of bioabsorbable polylactic acid coronary stents was designed, for which a finite element analysis method was used to carry out simulation analysis on blood flow field after the implantation of bionic texture stents with three different shapes (rectangle, triangle and trapezoid), thus revealing the influence of groove shape and size on hemodynamics, and identifying the optimal solution of bionic texture groove. The results showed that the influence of bionic texture grooves of different shapes and sizes on the lower wall shear stress region had a certain regularity. Specifically, the improvement effect of grooves above 0.06 mm on blood flow characteristics was poor, and the effect of grooves below 0.06 mm was good. Furthermore, the smaller the size is, the better the improvement effect is, and the 0.02 mm triangular groove had the best improvement effect. Based on the results of this study, it is expected that bionic texture stents have provided a new method for reducing in-stent restenosis.
【Abstract】ObjectiveTo compare the hemodynamic changes during operation of portal venous intubation or splenic venous intubation in extracorporeal venous bypass of swine orthotopic liver transplantation.MethodsThirty couples of healthy Duloke pigs were selected to perform orthotopic liver transplantation. According to the difference of cannula vessel of portal venous system during extracorporeal venous bypass, these pigs were divided into two groups: portal venous intubation group (n=15) and splenic venous intubation group (n=15). Hemodynamic changes were monitored continuously.ResultsTwo recipients died in portal venous intubation group, one died of unsmooth bypass in the operation, the other died of DIC. In splenic venous intubation group there was only one recipient death, who died of hemorrhagic shock. The time of anhepatic phase of splenic venous intubation group was (44.5±7.6) min, it was significantly shorter than portal venous intubation group(51.5±8.7) min(P＜0.05). Hemodynamic changes in phase Ⅲ and phase Ⅳ of portal venous intubation group were significantly different with that of splenic venous intubation group(P＜0.05). ConclusionApplication of bypass through splenic venous intubation during extracorporeal venous bypass of swine orthotopic liver transplantation can shorten the time of anhepatic phase, keep the hemodymamics relative stable in operation, and reduce the occurrence of postoperative correlative complication. It is an effective venovenous bypass pathway.
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.
Objective Comparing postoperative change of blood gas and hemodynamic status in patients underwent a right ventricletopulmonary artery (RVPA) conduit or a modified BlalockTaussig (mBT) shunt for pulmonary atresia with ventricular septal defect and without major arterial pulmonary collaterals (MAPCAs), to affirm the effect on oxygen supply /demand with different procedure. Methods From July 2006 to October 2007, 38 patients with pulmonary atresia and ventricular septal defect without MAPCAs were divided into two groups according to different procedures: RVPA group (n=25) and mBT group (n=13).Perioperative mortality, blood gas and hemodynamic data during postoperative 48 hours, including heart rate, blood pressure, systemic oxygen saturation, mixed venous oxygen saturation, oxygen excess factor, inotropic score were compared in both groups. Results The difference in the mortality between RVPA group (4.0％，1/25) and mBT group （7.7％，1/13) showed no statistical significance（Pgt;0.05）. The total of 33 patients were followed up, the followup time was from 6 to 18 months.11 patients (4 patients in mBT group, 7 patients in RVPA group) underwent corrected procedures during 9 to 18 months after palliative procedures, one case died of elevated pulmonary vascular resistance and right ventricle failure. The mixed venous oxygen saturation at 24h and 48h after surgery were higher than that at 6h after surgery (Plt;0.01) both in RVPA group and mBT group. The systolic blood pressures at 6h, 24h, 48h after surgery in RVPA group were lower than those in mBT group (P=0.048，0.043， 0.045)，the mean systemic blood pressures in RVPA group were higher than those in mBT group (P=0.048, 0.046, 0.049),the diastolic blood pressures in RVPA group were higher than those in mBT group (P=0.038, 0.034, 0.040)， the inotropic scores in RVPA group were lower than those in mBT group (P=0.035， 0.032，0.047). Conclusion The blood pressures and inotropic scores are found significantly different in RVPA conduit and mBT procedures, while postoperative systemic oxygen delivery areequivalent. Both RVPA and mBT patients decline to nadir in hemodynamic status at 6 h after surgery.
By using noninvasive venous plethysmography, venography and skin morphology, 44 patients (57 limbs) with chronic venous insufficiency (CVI) in lower extremity were studied , and compared with 12 normal subjects (24 limbs). The results showed that dermal nutrient disturbance caused by deep venous insufficiency accounted for 68%, and followed by perforating venous insufficiency was 44%. Furthermore compared venous refill time (VRT), segmented venous capacitancy (SVC) and maximum venous outflow (MVO) of dermal nutrient disturbance with those of exterior normal skin and normal subjects; and compared VRT, SVC, MVO of deep vein 3-4 stage reflux with those of 1-2 stage reflux and normal subjects,the differences were very significant (Ｐ＜0.05). Compared the VRT of perforating incompetence with that of competence (Ｐ＜0.01). Dermal pathology and ultramicrostructure showed that leucocytes trapping in capillary was a cause of microangiopathy. These results suggest that deep vein 3-4 stage reflux followed by calf perforating insufficiency was a main cause for dermal nutrient disturbance; lower extremity VRT reduced obviously and SVC increased significantly were hemodynamic character, leucocytes trapping in capillary was pathology basis of skin damage.
Objective To approach the effect of neck hyperextension position on hemodynamics of vertebral artery following thyroidectomy， and analyze the correlation between the change of hemodynamics and nausea and vomiting. Methods One hundred and fifty-eight patients with preparing for thyroidectomy （thyroidectomy group） and 89 patients with laparoscopic cholecystectomy （LC， LC group） were selected. The anesthesia method and the anesthesia drugs were the same in two groups. The indexes of hemodynamics of the bilateral vertebral artery at 6 h before and after thyroidectomy were measured. The difference of nausea and vomiting was observed and compared in two groups. Results The average blood flow velocity of the bilateral vertebral artery reduced and the blood flow decreased at 6 h after thyroidectomy as compared with at 6 h before thyroidectomy （P＜0.05）. The rates of nausea and vomiting of 0，2， 3， 4 times in the thyroidectomy group were significantly higher than those in the LC group （P＜0.05， P＜0.01）. The durations of nausea and vomiting of 1， 2， 3， 4 times in the thyroidectomy group were also significantly longer than those in the LC group （P＜0.01）. There was a positive correlation between the nausea and vomiting and the changes of blood flow velocity or blood flow （change of blood flow velocity：rs=0.697， P=0.03；change of blood flow：rs=0.897， P=0.01）. Conclusions There is a certain effect of the neck hyperextension position on hemodynamics of the bilatreal vertebral artery， and which might affect the nausea and vomiting following thyroidectomy.
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 observe the effect of lowering intraocular pressure(IOP) treatment on ocular hemodynamics in patients with nonarteritic anterior ischemic optic neuropathy (NAION). Methods A total of 68 patients with NAION (68 eyes) were enrolled in this study. The patients were randomly divided into treatment group (38 eyes of 38 patients) and control group (30 eyes of 30 patients). All the patients were received methylprednisolone pulse therapy (200 mg, three days), vasodilator therapy with intravenous infusion of Xueshuantong solution (300 mg), optic nerve nutritional therapy with mouse nerve growth factor (30 mu;g) and acupoint injection in temporal with compound anisodine (2 ml). The total course was 10 days. The patients of treatment group received IOP lowering treatment to reduce the IOP to ge;8 mm Hg (1 mm Hg=0.133 kPa) or in a 30% reduction. The patients of control group received no IOP lowering treatment. The peak systolic velocity (PSV), pulsatility index (PI) and resistance index (RI) of ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (PCA) before and after treatment were comparatively analyzed by color doppler flow imaging. Results The differences of PSV (t=1.023, 1.145, 0.569), PI (t=0.679, 0.956, 1.634) and RI (t=0.816, 1.657, 0.998) of OA, CRA and PCA before treatment in treatment group and control group were not statistically significant (P＞0.05). Compared with before treatment, PSV (t=3.150, 7.650, 3.520) and PI (t=2.420, 5.430, 7.650) of OA, CRA and PCA increased obviously (P＜0.05), RI of OA, CRA and PCA decreased obviously (t=5.320, 9.640, 18.360;P＜0.05) after treatment in treatment group. In control group, the differences of PSV (t=2.090, -2.550, -2.100) and PI (t=-2.310, -2.230, -4.490) of OA, CRA and PCA between before and after treatment were not statistically significant (P＞0.05); but the differences of RI of OA, CRA and PCA between before and after treatment was statistically significant (t=2.970, 2.160, 2.690;P＜0.05). Compared with control group, PSV (t=2.632, 2.135, 5.364) and PI (t=3.251, 2.432, 4.243) of OA, CRA and PCA increased obviously (P＜0.05), RI of OA, CRA and PCA decreased obviously (t=3.664, 2.938, 4.324;P＜0.05) after treatment in treatment group. Conclusion Lowering intraocular pressure treatment can improve the ocular hemodynamics in NAION patients.
