This study aimed to explore the specific application effect of specialist nursing intervention in intravenous therapy on elderly patients with peripherally inserted central catheters (PICC). From November 2023 to November 2024, a total of 60 elderly patients with PICC admitted to Guiqian International General Hospital were selected as research subjects. Using a digital random table method, these patients were randomly divided into a control group and an experimental group, with 30 patients in each. The control group received routine nursing care, while the experimental group received specialized intravenous therapy nursing intervention in addition to routine care. The nursing effects of both groups were comprehensively evaluated, including treatment compliance, psychological state, quality of life, incidence of complications, and satisfaction with nursing care. The results showed that after the intervention, the treatment compliance in the experimental group was significantly higher than that of the control group (P < 0.05). Additionally, scores on the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) were markedly lower in the experimental group compared to the control group (P < 0.05), indicating improved psychological well-being. The experimental group also scored higher in all dimensions of quality of life (P < 0.05), and had a lower complication rate and higher satisfaction with nursing care (P < 0.05). In conclusion, the application of specialized intravenous therapy nursing intervention in the care of elderly patients with PICC can significantly enhance treatment compliance, improve psychological status, elevate quality of life, and reduce complications, demonstrating strong clinical value and providing important guidance for future treatment and nursing of such patients.