Healthcare and Medicine Reference
Sampling: Blood-Taking and Cultures
Helen Parry and Lynn Lambert
University Hospital Birmingham, Birmingham, UK
Landmarks and anatomy
The antecubital fossa contains important vasculature for vene-
puncture. With the arm in the anatomical position and fl exed, the
biceps tendon is easily palpated and is located slightly medially
within the fossa. Medially is the basilic vein and this divides to
produce the median cubital vein (see Figure 5.1). The median cubital
By the end of this chapter you should be able to:
understand the indications and contraindications for phlebotomy
identify and understand the relevant anatomy
be aware of different types of blood sampling devices
describe the procedure of blood sampling
appreciate when to take samples for blood culture
use a blood culture sampling technique that minimises the risk
Cephalic vein pierces
Profi le testing, e.g. urea, electrolytes, liver function testing.
Investigation of specifi c diseases, e.g. cortisol in Cushing's
Monitoring of hormones, therapeutic drugs and tumour markers.
Toxicology, e.g. paracetamol levels.
Medial cutaneous nerve
Venesection for therapeutic management of polycythaemia rubra
Sampling according to research protocols (ensure that you have
Infection at the site of access, e.g. cellulitis.
Bleeding tendencies (relative contraindication), e.g. on warfarin
Taking sample from 'drip arm' (stop infusion and wait for at least
2 minutes before sampling).
Points of access
Antecubital fossa (this is the most commonly used site and
contains the basilic, cephalic and median cubital veins).
Forearm, hand and digital veins (these can often be accessed
using a butterfl y needle).
Figure 5.1 Venous drainage of the upper limb. (From Faiz O, Moffat D. (2006)
Anatomy at a Glance , 2nd edn. Blackwell Publishing, Oxford, with permission.)