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Skin to Intramuscular Compartment Thigh Measurement by Ultrasound in Pediatric Population
Myto Duong1,2, Albert Botchway3, Jonathan Dela Cruz1,2
1Southern Illinois University School of Medicine, Department of Surgery, Division of Emergency Medicine, Springfield, Illinois.
Insights
Pediatric obesity may require longer needles for intramuscular injections. Current epinephrine auto-injector needles might be too short for many children, potentially impacting medication effectiveness in emergencies.
Area of Science:
- Pediatric medicine
- Anaphylaxis management
- Medical device efficacy
Background:
- Childhood obesity rates are rising, posing challenges for effective intramuscular medication delivery.
- Existing epinephrine auto-injector needle lengths may be insufficient for obese pediatric patients, risking inadequate muscle compartment penetration.
Purpose of the Study:
- To determine appropriate needle length requirements for intramuscular injections in pediatric patients.
- To assess the impact of body mass index on subcutaneous tissue depth in children.
Main Methods:
- Ultrasound measurements of skin-to-muscle depth in the thigh were conducted on 200 pediatric patients.
- Patient data included weight and body mass index (BMI).
Main Results:
- Increased BMI correlated with greater distance to muscle and bone.
- A significant percentage of pediatric patients (5-11%) could receive inadequate intramuscular injections based on current guidelines.
Conclusions:
- Current needle lengths may be inadequate for effective intramuscular medication delivery in an increasing number of pediatric patients.
- Needle length guidelines for pediatric intramuscular injections require re-evaluation to account for increased skin-to-muscle depth due to obesity.
Introduction:
Pediatric obesity threatens the efficacy of medications given intramuscularly. In anaphylactic patients, epinephrine auto-injector needle lengths are potentially too short to reach the muscle compartment in patients with elevated body habitus. The objective of the study was to determine needle-length requirements for intramuscular injections in pediatric patients.
Methods:
We used ultrasound to measure the distance from skin to muscle compartment of the thigh in 200 pediatric patients of various weight and body mass index who presented to the emergency department.
Results:
Patients with higher body mass index had an increased distance to muscle and bone. If current recommendations were followed, 5% of patients within the EpiPen adult weight category and 11% of patients within the Centers for Disease Control and Prevention weight category would have potentially used a needle inadequate in length for intramuscular injections.
Conclusion:
With the increase in childhood obesity, needle lengths may be too short to effectively deliver medications to the intramuscular compartment. Needle length should be evaluated to accommodate pediatric patients with increased skin to muscle distance.
