Objective To explore the influence of dexmedetomidine on wake-up test during spinal orthopaedic surgery. Methods All 80 patients taking spinal orthopaedic surgery were randomly divided into the trial group and the control group, with 40 cases in each group. The endotracheal intubation anesthesia was adopted in both groups with same anesthesia induction. Additionally, dexmedetomidine 0.8 μg/ (kg·h) was infused within 10 min in the trial group before anesthesia induction, and then another 0.5 μg/ (kg·h) was also infused from the intraoperation to suture of incision. For the control group, the same amount of normal saline was infused, and all the narcotics were stopped pumping 15 min before the wake-up test, but then were continued pumping after the wake-up test. Finally, the following indexes were analyzed: wake-up time, wake-up quality, hemodynamic changes at the time of 15 min before wake-up (T1), recovery of spontaneous breathing (T2), wake-up (T3) and 15 min after wake-up (T4), dosage of narcotics, and the incidence of adverse events. Results There was no significant difference in the operation time before wake-up between the two groups (P=0.07). For the trial group, the dosage of sevoflurane (P=0.03) and sufentanil (P=0.00) used before wake-up was significantly lower, the wake-up time (P=0.04) and bleeding amount during wake-up (P=0.00) were significantly less, the wake-up quality (P=0.03) was significantly higher, the blood pressure (P=0.00) and heart rate (P=0.00) when wake-up were significantly lower, and the incidence of adverse events (P=0.04) was significantly lower, compared with the control group. Conclusion Dexmedetomidine adopted in spinal orthopaedic surgery can significantly improve patient’s wake-up quality, shorten wake-up time, reduce bleeding amount when wake-up and adverse events after wake-up, and maintain the hemodynamic stability, so it has better protective effects.
Objective To investigate change of bispectral index(BIS) and hemodynamic index during induction and orotracheal intubation of sevoflurane anesthesia. Methods This study was a prospective before-after study in the same patients. A total of 30 ASA physical status I and II adult patients without airway abnormalities were enrolled to receive inhalation induction of anesthesia with 8% sevoflurane. Mean arterial pressure(MAP),heart rate(HR) and BIS were recorded before anesthesia(T1),when patients loss of consciousness(T2), before intubation (T3),at 1 min(T4) and 3 min(T5) after intubation. Results BIS at T1-T5 were 96.8±1.7,70.4±8.8,39.2±8.4,43.6±12.9 and 41.6±9.3 respectively, the measurements at T2-T5 were all markedly lower than at T1(Plt;0.05). HR at T3-T5 were all markedly higher than at T1(Plt;0.05). MAP at T2 and T3 were markedly lower than at T1, but at T4 was higher than at T1(Plt;0.05), and recovered to the level at T1 at T5(Pgt;0.05).BIS,HR and MAP at T4 were all significantly higher than T3(Plt;0.05). Conclusion Anesthesia induction with sevoflurane and small dose of succinylchoiline we used can provide adequate depth of general anesthesia,but can not prevent cardiovascular adverse reactions to intubation.
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 investigate whether pulse pressure variation( ΔPP) reflect the effects of PEEP and fluid resuscitation ( FR) on hemodynamic effects. Methods Twenty critical patients with acute lung injury was ventilated with volume control ( VT =8 mL/kg, Ti/Te = 1∶2) , and PaCO2 was kept at 35 to 45 mm Hg. PEEP was setted as 5 cm H2O and 15 cmH2O in randomized order. Hemodynamic parameters including cardiac index, pulse pressure, central venous pressure, etc. were monitered by PiCCO system.Measurements were performed after the application of 5 cmH2O PEEP ( PEEP5 group) and 15 cm H2OPEEP ( PEEP15 group) respectively. When the PEEP-induced decrease in cardiac index ( CI) was gt; 10% ,measurements were also performed after fluid resuscitation. Results Compared with PEEP5 group, CI was decreased significantly in PEEP15 group( P lt;0. 05) , and ΔPP was increased significantly( P lt; 0. 05) . In 14 patients whose PEEP-induced decrease in CI was gt; 10% , fluid resuscitation increased CI from ( 3. 01 ±0. 57) L·min - 1·m- 2 to ( 3. 62 ±0. 68) L·min- 1 ·m- 2 ( P lt;0. 01) , and decreased ΔPP from ( 17 ±3) % to ( 10 ±2) % ( P lt;0. 01) . PEEP15 -induced decrease in CI was correlated negatively with ΔPP on PEEP5 ( r= - 0.91, P lt;0. 01) and with the PEEP15 -induced increase in ΔPP ( r = - 0. 79, P lt;0. 01) . FR-induced changes in CI correlated with ΔPP before FR ( r =0. 96, P lt; 0. 01) and with the FR-induced decrease in ΔPP ( r= - 0. 95, P lt; 0. 01) . Conclusions In ventilated patients with ALI, ΔPP may be a simple anduseful parameter in predicting and assessing the hemodynamic effects of PEEP and FR.
Objective To explore the hemodynamic monitoring value of pulse-indicated continuous cardiac output( PiCCO) during lung transplantation. Methods Twenty patients with end-stage lung disease undergone lung transplantation were enrolled. Hemodynamic states were monitored by PiCCO and Swan-Ganz standard thermodilution pulmonary artery catheter( PAC) simultaneously at six stages throughout the study. Changes in the variables were calculated by subtracting the first fromthe second measurement( Δ1 ) and so on ( Δ1 to Δ5 ) . Results The linear correlation between intra-thoracic blood volume index( ITBVI) and stroke volume index( SVIpa) was significant ( r = 0. 654, P lt; 0. 05) , whereas pulmonary artery wedge pressure ( PAWP) poorly correlated with SVIpa( P gt; 0. 05) . Changes in ITBVI correlated with changes in SVIpa ( Δ1 , r =0. 621; Δ2 , r = 0. 784; Δ3 , r = 0. 713; Δ4 , r = 0. 740; Δ5 , r = 0. 747; all P lt; 0. 05) , whereas PAWP failed. The mean bias between CIart and CIpa was ( 0. 09 ±0. 5) L·min-1 ·m-2 ; the limit of agreement was ( - 0. 89 ～1. 07) L·min-1 ·m-2 . Conclusions There is good correlation between the two methods of PiCCO and PAC for reflecting the change of heart preload. PiCCO is reliable in hemodynamic monitoring in patients undergone lung transplantation.
Abstract: Objective To investigate the in vivo effective orifice area (EOA) and whether prosthesispatient mismatch (PPM) is going to happen after 19mm St.Jude Regent valves replacement were performed. Methods Twentythree patients with valvular heart diseases were divided into 2 groups according to aortic annular diameter. 19mm St. Jude Regent valves were replaced in aortic valve place (Regent valve group), and 21mm other doubleleaflet mechanical valves were replaced in aortic place (other valves group). All of the operations were accomplished under cardiopulmonary bypass in West China Hospital. All of the patients were followed up in 3 to 6 months after their surgery processes. Color Doppler echocardiography was used to measure the hemodynamic parameters in their followup. Then left ventricular mass (LV mass), EOA and effective orifice area index (EOAI) etc. were calculated and compared by using SPSS 12.0. Results No cardiac episodes were detected during the perioperative period and 36 months after operation. LVmass reduced in 36 months after operation in both groups. No statistical significance of EOA, EOAI and LVmass reduction were detected between the two groups. Conclusions (1)The EOA and in vivo hemodynamic effects of 19mm Regent valve are similar to 21mm other double leaflet mechanical valve. (2)It is safe to use 19mm Regent valve in those patients whose aortic annular diameter are small and need double valve replacement. Using 19mm Regent valve will not cause short time cardiac episodes and PPM. (3)More further works should be done to make sure what is the standard of PPM in Chinese people, such as enlarging the patients number and prolonging the followup time. (4) Further clinical and followup works should be done to make St.Jude Regent valve’s feature out.
Objective To investigate the feasibility of a long-term left ventricular assist device placed in the aortic valve annulus for terminal cardiopathy. Methods An implantable aortic valve pump （23ram outer diameter, weighing 31g） was developed. There were a central rotor and a stator in the device. The rotor was consisted of driven magnets and an impeller, the stator was consisted of a motor coil with an iron core and outflow guide vanes. The device was implanted identical to an aortic valve replacement, occupying no additional anatomic space. The blood was delivered directly from left ventricle to the aortic root by aortic valve pump like natural ventricle, neither connecting conduits nor ＂bypass＂ circuits were necessary, therefore physiologic disturbances of natural circulation was less. Results Aortic valve pump was designed to cycle between a peak flow and zero net flow to approximate systole and diastole. Bench testing indicated that a blood flow of 7L/min with 50 mmHg（1kPa = 7.5mmHg） pressure could be produced by aortic valve pump at 15 000r/min. A diastole aortic pressure of 80mmHg could be maintained by aortic valve pump at 0L/min and the same rotating speed. Conclusions This paper exhibits the possibility that an aortic valve pump with sufficient hemodynamic capacity could be made in 23mm outer diameter, 31g and it could be implantable. This achievement is a great progress to extend the applications of aortic valve pump in clinic and finally in replacing the natural donor heart for heart transplantation. Meanwhile, this is only a little step, because many important problems, such as blood compatibility and durability, require further investigation.
Objective To analyse the characteristic of hemodynamic changes during off-pump coronary artery bypass grafting （OPCAB）. Methods One hundred consecutive patients received OPCAB and the hemodynamic changes were monitored during the grafts was anastomosed. They were anastomosis of the left internal mammary artery （LIMA） to left anterior descending （LAD） in 97 patients, the anastomosis of saphenous vein （SV） or radial artery（RA） to right coronary artery （RCA） including posterior descending artery （PDA） and posterior left branch （PLB） in 84 patients, to left circumflex coronary artery （LCX） in 50 patients, to optuse marginal artery（OM） in 27 patients, to diagonal artery （DG） in 25 patients. The grafts number in each patient was 3. 1±0. 7. Results Hemodynamics changed when LAD and DG were anastomosed with significantly increase of heart rate （HR）, significantly decrease of mean arterial pressure （MAP） and left ventricular stroke work index （LVSWI, P〈0.05）. Hemodynamics changed when LCX,PDA,PLB,OM were anastomosed with significantly increase of HR and center veinous pressure （CVP, P 〈 0. 05）, significantly decrease of MAP, cardiac index （CI）, stroke index （SI）, right ventricular ejection fraction （RVEF）, right ventricular end-diastolic volume （RVEDV）, LVSWI and right ventricular stroke work index （RVSWI,P〈0.05）. Hemodynamics tended to be stable and CI improved at the end of operation. Conclusion There are no or little hemodynamic changes during the LAD and DG were anastomosed in OPCAB, while hemodynamics changed significantly during LCX, PDA, PLB and OM were anastomosed. Hemodynamics become stable and CI improves after operation.
Objective To observe the midterm haemodynamic manifestation of the home made C-L pugestrut tilting disc mechanical valve in aortic valve replacement, and to evaluate its function. Methods Twenty patients underwent aortic valve replacement over 5 years were collected and divided into two groups, the C-L pugestrut group （n=10）：aortic valve was replaced by home-made C-L pugestrut tilting disc mechanical valve（21mm）; Medtronic-Hall group （n=10）：aortic valve was replaced by Medtronic-Hall mechanical valve （21mm）. The peak transprosthetic gradients （△P）, mean transprosthetic gradients （△Pm）and effective orifice area（EOA） at rest were compared between two groups. Results At rest, △P of the C-L pugestrut group and Medtronic-Hall group were 11.63±3.23mmHg vs. 9. 78±3. 35mmHg; △Pm of the C-L pugestrut group and Medtronic-Hall group were 6. 25±2. 32 mmHg vs. 5.85±2.32mmHg： EOA of the C-L pugestrut group and Medtronic-Hall group were 1.07±0.17 cm2 vs. 1.25±0.27 cm2. There was no statistically significance in △P, △Pm and EOA between two groups（P〉0.05）. Conclusions The midterm haemodynamic results of the home-made C-L pugestrut tilting disc mechanical valve show that it has comparable haemodynamic results to those of Medtronic-Hall mechanical valve ,and it has well-done function. The home-made C-L pugestrut valve is one of the reliable mechanical heart valves.
Objective To investigate the hemodynamic performance of valved bovine jugular vein conduits (BJVC) for right ventricular outflow tract reconstruction in canine model. Methods The BJVC that were treated with the glutaraldehyde were implanted between the pulmonary artery and right ventricle in seven young canines. Right ventricular and pulmonary artery pressures were measured directly before and after the implantation. Hemodynamic evaluations were carried out by echocardiography and cardiac catheterization after the implantation. Results Seven canines were survival one year after the implantation. The pulmonary artery pressures (including systolic pressure, diastolic pressure and mean pressure) had not significantly changed after reconstruction with the conduits. The right ventricular diastolic pressures had not increased after the reconstruction, but the right ventricular systolic pressure and mean pressure had increased. One year later, the echocardiography showed valve motion with no obvious thickening of the leaflets. No graft kinking or obvious regurgitation of the valve was observed. Cardiac catheterization and angiography showed that the pressure gradients between the right ventricle and the conduits varied from 3 to 19mmHg, the diastolic pressures in the conduits were higher than that of right ventricle((Plt;)0.01), and the conduits and pulmonary arteries had no obvious obstruction. Conclusion The glutaraldehyde-fixed bovine jugular vein conduit has good hemodynamic performance in the pulmonary circulation.