Objective\ To investigate the clinical significance of measuring central venous pressure in patients after cardiac surgery.\ Methods\ Twenty four patients in postoperative cardiac surgery were randomly chosen, and investigated under three fettles:(1) The patients were sent into intensive care unit on mechanical ventilation; (2) They were all conscious and on mechanical ventilation 8 hours after operation; (3) 24 hours after operation, the patients were conscious with normal breathing.
Objective To observe the survival rate of reversed-flow free flap after anastomosing one venous reverse flow and to explore the change of intravenous pressure and mechanism of venous reverse flow. Methods Thefree vascularized posterior tibial flap with reversed flow was successfully established in NewZealand white rabbits.Fifteen rabbits were randomly allocated into 3 groups of 30 flaps. In group A,two vena comitans were anastomosed.In groups B and C,only onevenae comitans was anastomosed. In groups A and B,intravenous pressure was measured immediately and 30,60 and 120 minutes after anastomosing the vascular pedicle.Flap survival rate of group B was measured after two weeks. In group C, radiography of one venae comitans was observed.The diameters of posterior tibial vessels was measured on all the rabbits before anastomosing the vascular pedicle. Results The diameters of posterior tibial artery was 8.0±0.3mm and of vena comitans was 11.0±0.5 mm。The intravenous pressure of group B increased rapidly and reached its top value after about 30 minutes (P＜0.05).It then decreased and approached normal level after about 60 minutes (Pgt;0.05).The intravenous pressure was not significantly different between groups A and B in each time interval (Pgt;0.05).Two flapsresulted in avulsion,infection and necrosis.The remaining 8 flaps survived completely.Most of the radiopaque in group C flew back to the proximal tibia one hourlater. Conclusion Venous retrograde return is abundant in reverseflow free flap of anatomosing one vena comitans.The main way of venous reflux in reverseflow free flap can be through “direct incompetent valve route”.
Objective To explore the effect of cyclopamine （Cyc） which is the inhibitor of the Hedgehog signaling pathway on portal venous pressure of normal and liver cirrhosis rats, and it’s possible mechanisms. Moreover, to provide the experimental basis of drug efficacy and clinical treatment. Methods Thirty two healthy male SD rats were randomly average divided into four groups：normal control group, normal treatment group, liver cirrhosis control group, and liver cirrhosis treatment group. The liver cirrhosis models of rat were established by using the thioacetamide （TAA） method, which made 0.03% of TAA as the initial water concentration, and then the concentration of TAA in drinking water was adjusted according to the changes of the weekly body weight of rats lasting for twelve weeks. In thirteenth week, intraperitoneal injection of corn oil （0.1 ml/100 g body weight, 1 time/d） were performed lasting for a week in rats of the normal control group and liver cirrhosis control group; intraperitoneal injection of Cyc 〔1 mg （0.1 ml）/100 g body weight, 1 time/d〕were performed lasting for a week in rats of the normal treatment group and liver cirrhosis treatment group. In fourteenth week, the liver function, portal venous pressure （PVP）, and the ration of liver or spleen weight to body weight were detected, the expressions of α-smooth muscle actin （α-SMA） and typeⅠcollagen α1 （Col1α1） of hepatic stellate cell were detected by using immunohistochemistry. Results PVP were （10.7±0.9） and （12.3±1.3） cm H2O （1 cm H2O=0.098 kPa） in normal control group and normal treatment group, respectivly, the latter was higher than the former （t=-2.918，P=0.011）. PVP were （21.8±0.7） and （14.3±1.4） cm H2O in liver cirrhosis control group and liver cirrhosis treatment group, respectivly, the latter was lower than the former（t=13.602，P=0.000）. The expressions of α-SMA and Col1α1 in liver cirrhosis treatment group was lower than the liver cirrhosis control group. There were no significant difference of the liver function and ration of liver or spleen weight to body weight between the treatment group and the control group （P＞0.05）. Conclusion Cyclopamine could signally reduce the PVP of liver cirrhosis rats through reducing the expressions of α-SMA and Col1α1.
ObjectiveTo investigate the influence of norepinephrine on pulmonary vessel pressure in animal model of septic shock. MethodsTwelve health mongrel dogs were randomly divided into a control group (n=5, intravenously injected with normal saline 1 mL/kg) and an endotoxin group(n=7, intravenously injected with lipopolysaccharide 1 mg/kg). When the systemic blood pressure decreased by more than 40% of baseline before administration, the dogs in two groups were intravenously injected with NE 0.5, 1.0, 2.0, 5.0μg·kg-1·min-1. The interval of each dose was more than 10 minutes. The changes of the pulmonary arterial pressure (PAP), pulmonary venous pressure (PVP), and systemic arterial rressure (SAP) were recorded and compared between two groups. ResultsIn the control group, PAP didn't change significantly after administration (P < 0.05), however, PVP increased obviously after NE administration in dose of 2.0 and 5.0μg·kg-1·min-1 (P < 0.05), and SAP increased obviously after NE administration in dose of 1.0, 2.0 and 5.0μg·kg-1·min-1 (P < 0.01). In the endotoxin group, PAP increased obviously after NE administration in dose of 2.0 and 5.0μg·kg-1·min-1 (P < 0.05), while PVP didn't change significantly (P > 0.05), and SAP increased obviously after NE administration in dose of 1.0, 2.0 and 5.0μg·kg-1·min-1 (P < 0.05). There were significant differences in SAP (P < 0.05), not in PAP and PVP (P > 0.05), between two groups after NE administration at dose of 1.0, 2.0 and 5.0μg·kg-1·min-1. The PVP/SAP and PAP/SAP values didn't change significantly after administration in the control group (P > 0.05). In the endotoxin group, the PVP/SAP and PAP/SAP values increased significantly after LPS administration, and decreased slightly after NE administration in dose of 2.0 and 5.0μg·kg-1·min-1 (P < 0.05). ConclusionsNE administration in septic shock can not increase the angiotasis of the pulmonary vein. NE administration in dose of 2.0 and 5.0μg·kg-1·min-1 can cause the increase of PAP and SAP, but the increase of PAP is lower than the increase of SAP.
ObjectiveTo evaluate the value of clinical application of determination of lower venous pressure in the diagnosis and treatment of deep venous thrombosis (DVT). MethodsThe 90 patients with DVT of unilateral lower limb who were admitted by using color Doppler or deep veins of lower limb angiography in our hospital during the period of 2013 July to 2014 June were selected and as the research object (case group), 37 cases were male, 53 cases were female; the age was 18-84 years old, mean age was 59.48 years old. According to the development of disease, 90 cases were divided into acute 30 cases, subacute 30 cases, and chronic 30 cases; and according to the pathological types were divided into the central type in 30 cases, 30 cases of peripheral type, and 30 cases of mixed type. At the same time the without lower extremity DVT volunteers of 20 cases were selected as normal control group, including male 9 cases, female 11 cases; age was 21-65 years old, average age was 38.7 years old. The static venous pressure (P0), dynamic venous pressure (P00), and decreased pressure ratio (Pd) of double lower limbs of participants in 2 groups were determinated and comparative analyzed. ResultsThe P0 and P00 of patients with different development of disease and pathological types of the case group were higher than those of the normal control group (P < 0.01), and the Pd was lower than that of the normal control group (P < 0.01). In case group, the P0 and P00 of acute phase were higher than those of the normal control group (P < 0.01), the P0 of central type was higher than that of the peripheral type and mixed type (P < 0.01), and the Pd central type was lower than that of mixed type (P < 0.01). The above 3 indexes' differences of double lower limbs in the normal control group had no statistical significance (P > 0.01). In case group, the P0 and P00 of ipsilateral limb in different development of disease and pathological types were higher than those of the healthy limb, and the Pd were lower than that of the healthy limb (P < 0.01). ConclusionsLower extremity venous pressure measurements can be used in clinical detection for early lower limb DVT, and can be used as the objective index of clinical evaluation curative effect for the treatment of DVT. It is a simple and practical clinical detection method.
ObjectiveTo investigate various methods and strategies of lowering central venous pressure (CVP) during hepatectomy.MethodThrough literature review, the definition, implementation, related complications, and prognosis of low CVP were reviewed and summarized and the most appropriate CVP in the liver surgery was also summarized.ResultsThe low CVP had been widely applied in the different clinical settings. Its effect of reducing hemorrhage and transfusion had been recognized. There were many techniques to intraoperatively reduce the CVP such as the volatile anesthetics, vasoactive agents, fluid restrictive strategy, inferior vena cava clamping, low tidal volume, etc. However, there was no consensus on the best strategy to reduce the CVP and there were no studies focusing on the prognosis of patients underwent the low CVP hepatectomy. Maintaining the CVP between 2.1–3 mm Hg (1 mm Hg=0.133 kPa) intraoperatively might be appropriate, once the section had been made normal hemodynamic state of the patient should be restored immediately.ConclusionsApplication of low CVP could reduce blood loss and transfusion in hepatectomy. Prognosis of patients receiving low CVP is not clear. Application of low CVP in specific population should be cautious.
Controlling intraoperative bleeding is the core technology of liver surgery, and it is also an important way to improve the benefits of liver surgery and reduce the risk of surgery. In recent years, a number of methods to maintain low central venous pressure have been proposed, including inferior vena cava clamping, restricted fluid infusion, postural changes, intraoperative assisted ventilation, intraoperative hypovolemic venous incision, etc. In addition, more and more indicators used to guide intraoperative fluid input management to maintain low central venous pressure have been discovered, including global end-diastolic volume and stroke volume variability. Therefore, this article summarizes the relationship between low central venous pressure and surgical effect in liver surgery, and the ways to achieve low central venous pressure on the basis of previous research.
Venous pressure monitoring is an important indicator for the arteriovenous fistula evaluation. Direct static venous pressure monitoring is recognized as the most accurate way of venous pressure monitoring, which is widely used in the functional monitoring, functional evaluation of arteriovenous fistula, the diagnosis of complications and the evaluation of surgical efficacy. Venous pressure monitoring has obvious advantages and disadvantages, so it is necessary to improve relevant knowledge to correctly guide clinical diagnosis and treatment. In this paper, the study of static venous pressure monitoring of arteriovenous fistula was summarized, in order to improve the understanding of the significance and clinical application of static venous pressure monitoring of arteriovenous fistula.