The objective of this study was to survey incidence of peripheral phlebitis in surgical elderly patients. MATERIALS and METHODS BACKGROUND FACTORS ASSOCIATED PHLEBITIS IN ELDERLY PATIENT S Yaowarat Hinsui, RN, MSc., Pavinee Sukondhavich, RN, BNs., Karuna Krungkaew, RN, BNs. Nursing Department, Siriraj Hospital, Mahidol University, Bangkok. Thailand About 33.1% of patients who admitted in surgical department, Siriraj hospital are elderly (Pittayapan,et al, 2006). Treatment of this patients are intravenous therapy, parenteral nutrition and intravenous medication administration. The procedure of treatment prone to phlebitis because of acid-base and osmolarity of this solutions were high. Venipuncture process in elderly patients risk to phlebitis because they have thin layer of vessel and bacterial infection (Masoorli S,2005). Prevalence of elderly patients in our unit was high in each year and phlebitis is the problem of nursing care. So we want to survey incidence of phlebitis and associated factors on phlebitis in elderly surgical patients. This survey research was conducted on The subject were 447 patients who have sixty years or over that admitted in surgical department, Siriraj hospital and they have 1,154 sites of insertion. Data were record in computerization and analyzed by descriptive statistic. CONCLUSION The incidence of phlebitis in surgical elderly patients were 5.72 percent. They are many factors associated phlebitis. Elderly patients are change in pathophysilogy of skin and vein which prone to be phlebitis. The other factors associated phlebitis are type of solutions, intravenous medicines, type and size of needle, type of dressing. Nurse who are care this patients must have skill and aware for intravenous administration to complication prevention. OBJECTIVE REFERENCE 1.Sue Masoorli. (2005) Geriatric IV Therapy Tips. 2.Danchaivijirt S, et al. Infusion Phlebitis in Medical and Surgical Patients in Siriraj Hospital. Journal Med Associate Thai. July; Maki, D.G., & Ringer, M. Risk factors for infusion related phlebitis with small peripheral venous catheters. Annals of Internal Medicine,1991;114(10), Lewis GB, et al. Infusion Thrombophlebitis. Br J Anaesth. 1985; 57(2): The subjects of this study were male (64%) and female (36%) elderly patients. Mean of age were 76 years old. They admitted in surgical ward that divide to gastrointestinal (22.27%), neurological (16.29%), orthopedics (15.86%), urological (13.6%) and vascular surgery (9.71%). The most site of insertion are forearm (45.93%) and dorsum of hand (43.67%). Characteristic of vein are soft (44.89%) and resilient (16.46%). The number of needle are 24 and 22 gauge, 33.8 and percent, respectively. Type of dressing are fixomull no gauze (44.71%), gauze (29.38%) and transparency dressing (24.7%). Type of intravenous medicine are cephalosporin (42.35%), penicillin (16.52%) and metronidazole (8.87%) as show in figure 1. Incidence of phlebitis are 5.72% and grade of phlebitis are 1-4 as show in figure 2. Figure 2 Percent of Plebitis Figure 1 Type of Antibiotics RESULTS