Blood samples for glucose tests should be taken from the earlobe rather than thumb, a study has concluded. Lancet skin puncture of the earlobe is less painful than that of the thumb, say Dr Simon Carley (specialist registrar in emergency medicine, Manchester Royal infirmary) and colleagues.
In a study of 60 patients, blood sampling at the earlobe and lateral aspect of the thumb were compared. Previous studies had shown that sampling from the thumb was less painful than from the finger or elbow (PJ 1999:263:412). The authors found that pain scores were lower in the earlobe group and suggest that the density of nociceptors may be lower in the ear or that low pain scores were the result of the patient being unable to see the puncture of the earlobe. While failure rate was slightly higher in the earlobe group, the authors say that the study was too small to detect a true difference. However, failure rate was low in both groups (British Medical Journal 2000;321:20).