Why does the blood vessel remain hardened and swollen for three months after intravenous infusion, and what should be done about it?
After intravenous infusion, blood vessels may remain hardened and swollen for up to three months. This could be caused by individual differences, improper operation, allergic reactions, thrombosis, or phlebitis. It is recommended to manage the condition through massage, selecting appropriate infusion sites, and using medications. It is advised to visit a hospital to determine the exact cause and follow medical advice for treatment. The analysis is as follows:

1. Individual Differences: People differ in physical conditions and physiological structures, leading to varied responses to intravenous infusions. Some individuals may have weaker vascular recovery after infusion, making them more prone to hardened and swollen blood vessels, which may persist for an extended period. Applying a warm towel or hot water bottle to the affected area and performing gentle massage may help promote blood circulation and reduce inflammation.
2. Improper Operation: During infusion, if healthcare providers lack sufficient skill in venipuncture, surrounding tissues may become damaged, causing the blood vessel to harden. Additionally, if the needle clamp is too tight or the vessel is bruised, localized inflammation may occur, resulting in vessel hardening and swelling. In future infusions, medical staff should carefully select infusion sites, avoid repeated punctures at the same location, and adjust the infusion rate appropriately to prevent it from being too fast or too slow.
3. Allergic Reaction: Some medications are highly irritating and may trigger allergic reactions. Allergies can cause blood vessel constriction and spasms, leading to vessel hardening. Symptoms such as pain, itching, and difficulty breathing may also accompany the reaction. If necessary, antiallergic medications such as cetirizine hydrochloride tablets, loratadine tablets, or ebastine tablets may be used under medical guidance.
4. Thrombus Formation: The insertion of catheters during intravenous infusion may increase the risk of blood accumulation within the vein, potentially leading to thrombus formation. A clot can cause the vein wall to harden, swell, and bulge, and may take a long time to be absorbed and resolve. As directed by a physician, medications that improve blood circulation—such as ginkgo leaf capsules, xueshuantong capsules, or salvia miltiorrhiza tablets—may be used for treatment.
5. Phlebitis: Phlebitis is an inflammatory reaction of the inner lining of a vein, possibly caused by drug irritation, excessively rapid infusion rates, or prolonged infusion at the same site. It can lead to redness, swelling, and pain around the vein, along with hardening and bulging of the vessel. If not treated promptly, phlebitis may worsen and even affect subsequent treatments and recovery. Patients should use medications such as dexamethasone tablets under a doctor’s guidance to aid recovery.
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