Central anticholinergic syndrome or postoperative residual block?

EDITOR: I read with interest Dr Katsanoulas and colleagues' description of two cases of presumed anticholinergic syndrome [1]. However, quite a few of the signs and symptoms of the first case (a 70-kg, 60-year-old man) are quite similar to those seen in connection with severe residual neuromuscular block (signs of upper airway obstruction, rise in blood pressure and heart rate and agitation). The effects seen later after the injection of physostigmine 2.5 mg i.v. do not contradict the idea that the symptoms, at least partly, were due to severe residual block following cisatracurium Did the authors monitor neuromuscular block per- and postoperatively? If so, what was the response to the nerve stimulation when neostigmine was given for the first time? If not, were there any signs of spontaneous muscle activity when neostigmine was given? Did you ask the patient afterwards whether or not he had had symptoms of residual block? Please note, that a normal tidal volume and normal oxygenation do not exclude significant residual block. J.