To the Editor:
We read with interest the letter of Moorthy and Dierdorf  about pain on injection of rocuronium. With subparalyzing doses, they noticed that "most" patients had "severe burning pain" on injection of the rocuronium.
We have noted in 105 consecutive patients requiring subparalyzing rocuronium the indicence of pain on injection of the rocuronium. The site of injection, the age and sex of the patients, and the degree of pain (mild, moderate, severe) were also noted. Using chi squared tests, the relation between site of injection and pain and between the sex of the patient and the pain were analyzed. No relationship was seen between site of injection or sex of the patient and the pain on injection. Fifty-two patients of the 105 had pain on injection of rocuronium. Of these 52 patients, 13 (12%) patients had what they described as severe pain.
These results suggest that rocuronium is not suitable for use as a subparalyzing dose before succinylcholine or in priming. Priming has also been shown to be of little value [2,3] in speeding the onset time of rocuronium. The patient should probably be asleep before rocuronium is administered to the patient.
M. A. H. Steegers, MD
E. N. Robertson, FRCA
Department of Anesthesiology
Academisch Ziekenhuis Nijmegen
Nijmegen, The Netherlands
1. Moorthy SS, Dierdorf SF. Pain on injection of rocuronium. Anesth Analg 1995;80:1067.
2. Tryba M, Zorn A, Thole H, Zenz M. Rapid-sequence orotracheal intubation with rocuronium: a randomized double-blind comparison with suxamethonium-preliminary communication. Eur J Anaesthesiol 1994;11(Suppl 9):44-8.
3. Feldman SA. Rocuronium-onset times and intubating conditions. Eur J Anaesthesiol 1994;11(Suppl 9):49-52.