Comparing peripheral venous access between obese and normal weight children

Introduction: Intravenous (i.v.) access is sometimes a difficult, time-consuming, and highly frustrating procedure. Obesity is widely believed to be associated with difficult peripheral intravenous access (PIV) placement. This study examined the relationship between body mass index (BMI) and ease of venous access in children undergoing noncardiac surgical procedures.

Methods: We prospectively collected data on children aged 2–18 years undergoing elective noncardiac surgery at our institution. A trained research assistant (RA) was present for PIV placement in all patients and noted the following: age, gender, ethnicity, weight, height, and BMI. We also collected data on i.v. insertion site, number of attempts, number of operators, and the number of i.v. cannula used. The main outcome variable was success or failure of i.v. placement on first attempt. Sample size calculation indicated a need for 40 obese and 40 control patients.

Results: A total of 103 (56 lean and 47 obese) patients comprised the study population. PIV cannulation was achieved on the first attempt in 55.2% while 39.6% of patients had 2–3 attempts before successful cannulation. Obese children were more likely to have failed attempt at first cannulation than lean controls (P < 0.001). Similarly, obese children were more likely to require two or more attempts at cannulation than lean children (P < 0.001).

Conclusion: These data indicate that i.v. placement is more difficult in obese children than their lean peers and that the most likely site for successful placement in obese children after a failed attempt on the dorsum of the hand is the volar surface of the hand. Knowledge of potential sites for successful i.v. access could help to improve the success rate for i.v. placement.