Does wearing two pairs of gloves protect against skin contamination?

incapacitating systemic disease which is a constant threat to life; and ASA V, moribund patient, not expected to live for 24 hours with or without surgery) abnormal values were found in 1-5% of patients in grade I, 17% in grade II, 35% in grade III, and 48% in grades IV and V.' In addition, most abnormal values in patients in grade II were minor and not clinically important. Therefore patients in grades I and II do not need routine estimations of urea and electrolyte concentrations whereas those in grades III, IV, and V do, as the results are much more likely to be abnormal. I therefore suggest that this grading system, which could be easily learnt by junior medical staff, would be more appropriate than age as an indicator of the need for biochemical screening preoperatively. 1 McCleane GJ. Urea and electrolyte measurement in preoperative surgical patients. We agree with Drs Ian T Campbell and Peter Gosling (1 October, p 803) that routine pre-operative biochemical screening is unnecessary and not cost effective in patients under 50. Blood tests by either venepuncture or finger pricking can be an unpleasant part of any hospital stay, but this is especially so in children, and we have specifically examined the value of routine preoperative blood tests in paediatric orthopaedic practice at the Royal Liverpool Children's Hospital, Alder Hey. ' One of our conclusions was that preoperative estimation of serum urea and electrolyte concentrations and full blood counts are unnecessary in healthy children. Out of 346 patients admitted for elective operation, 28 (8-1%) underwent estimations of serum urea and electrolyte concentrations. Two had abnormal results, both patients who had developed renal failure. We also agree that the inexperience of junior staff is often an important factor in unnecessary, excessive blood testing. As it is unlikely that our specialty is alone in this respect we strongly urge others operating on children to review their policies. 1 Jones MW, Harvey IA, Owen R. Do children need routine preoperative blood tests and blood cross matching in ortho-paedic practice? Ann R Coll Surg Engl (in press). Drug Tariff increases I sympathise with Dr J D Beale (15 October, p 981), who throws away his new copy of the Drug Tariff every month, and I agree that this is a shameful way to waste the nation's money. Dispensing doctors such as myself, however, make frequent use of the Drug Tariff, …