Experimental Study Of Intravenous Indwelling Needle On Vascular Injury

Objectives:By means of animal experiment study with the application of intravenous indwelling needle injection of three different types of drugs including doxorubicin chemotherapy drugs, mannitol solution and physiological saline, this thesis is to observe pathological injury degree of the blood vessels in different indwelling times and to study the optimal indwelling time at the condition of no irreversible pathological injury caused by intravenous indwelling needle injection of different types of drugs.Methods:Through inclusion and exclusion criteria, 60 healthy large-eared New Zealand rabbits were evenly divided into three groups randomly. The veins at the edges of the two ears were taken out as the tested blood vessels for the infusion with intravenous indwelling needle. The three groups were injected respectively with Doxorubicin, 20% mannitol and physiological saline once daily, blocked with heparin salt water. After intraperitoneal anesthesia, pathological sections were prepared by taking 5.5cm-long and 1cm-wide live Samples from the ear vein where intravenous indwelling needle puncturing on the 2nd, 4th, 6th, 8th and 10th day of transfusion. Specimen was obtained to be routinely ethanol dehydrated in 10% paraformaldehyde fixative, waxed, embedded. Each specimen was sliced respectively at the point of 0.5cm far from heart ,the point of 0.5cm near the heart, the end of the indwelling needle, the point of 0.5cm and 1.5cm on the end of the indwelling needle.All slices were obtained to be stained with hematoxylin and eosin.Then Pathological changes of vascular and peri-vascular tissues were observed under the light microscope. Results:1. In the same indwelling time, the incidence of inflammation and thrombosis in two groups of the Doxorubicin and mannitol are more severe than that of the physiological saline group. The inflammation difference is of statistic significance after 4 days(x2 =8.976, p<0.05), and the thrombosis difference is of statistic significance after 6 days (x2 =8.023, p<0.05).2. At 5 different slices for the same group, the inflammation and thrombosis are generated more possibly at the point of 0.5cm near the heart and the end of the indwelling needle, while they are generated less possibly at the point of 0.5cm far from heart and the point of 0.5cm and 1.5cm on the end of the indwelling needle. The difference is of statistic significance (inflammation response p<0.001;thrombosis p<0.01)3. The inflammation and thrombosis are different for the same group at different indwelling times. With the extension of the indwelling time, the inflammation becomes severe gradually and the thrombosis becomes more and more. The difference for the groups with the injection of doxorubicin and mannitol is of statistic significance(inflammation response p<0.05;thrombosis p<0.05).And for the group with the injection of physiological saline,inflammation also has significant statistic difference at different indwelling times(p<0.05).The thrombosis is different, but there is no statistic difference(p>0.05).Conclusions:1. The injury degree of the blood vessels is relevant to the physical and chemical properties of the injected drugs. The main factors inducing the inflammation are the injected drugs with high stimulation and concentration.2. The inflammation and thrombosis are relevant to mechanical stimulation of the indwelling needle. The inflammation and thrombosis are generated more possibly at the point of 0.5cm near the heart and the end of the indwelling needle, the injury degree of the blood vessels is most severe.3. The inflammation and thrombosis are relevant to the indwelling time. The indwelling time of intravenous indwelling needle should not be the same. When intravenous catheter system was injected with strong irritant substances, the suitable indwelling time was 2d, no more than 3d.When injected with the weak irritant drugs, the indwelling time may be appropriate to extend, but preferably not more than 7d.