1. "Pentavalent vaccine and the new pneumococcal vaccine (PCV10) are injected intramuscularly into the opposite thighs" (Immunization Module: Vaccine Preparation and Administration Routes of the EPI Vaccines, n.d.).
Vastus lateralis site
Vastus lateralis
Origin: Lateral intermuscular septum, lateral lip of the linea aspera and the gluteal tuberosity
Insertion: Patella and medial patellar retinaculum
Action: Extends leg
How to locate: To landmark the vastus lateralis, position the patient lying down or being held by a parent. Palpate the muscle below the greater trochanter and above the lateral femoral condyle (knee joint). Divide the muscle into thirds and administer the injection into the middle third of the muscle, in the outer anterolateral aspect, lateral to the midpoint of the thigh.
2. "For adults [aged 19 years or older], the deltoid muscle is recommended for routine intramuscular vaccinations" (ACIP Vaccine Administration Guidelines for Immunization | CDC, n.d.).
Deltoid muscle site
Deltoid muscle
Origin: Lateral one-third of the clavicle, acromion, the lower lip of the crest of the spine of the scapula
Insertion: Deltoid tuberosity of the humerus
Action: Abducts arm; anterior fibers flex & medially rotate the arm; posterior fibers extend & laterally rotate the arm
How to locate: Above the level of the armpit and approximately 2-3 fingerbreadths (~2") below the acromion process
References
ACIP Vaccine Administration Guidelines for Immunization | CDC. (n.d.). https://www.cdc.gov/vaccines/hcp/acip-recs/general-recs/administration.html
How to Administer Intramuscular and Subcutaneous Vaccine Injections to Adults. (n.d.). Immunize.org. http://www.immunize.org/catg.d/p2020a.pdf
Immunization Module: Vaccine Preparation and Administration Routes of the EPI Vaccines. (n.d.). https://www.open.edu/openlearncreate/mod/oucontent/view.php?id=53352&printable=1
Nursing guidelines : Intramuscular Injections. (n.d.). https://www.rch.org.au/rchcpg/hospital_clinical_guideline_index/Intramuscular_Injections/
Univ of Michigan - Gross Anatomy - Muscles Tables. (n.d.). Copyright 2000 the University of Michigan. https://www.med.umich.edu/lrc/anatomy-tables/muscles_alpha.html