I wish to comment on the letter by Bullough and Craig  about the anaesthetic management of the professional singer. In my opinion, the careful protocol they have followed is correct and elegant, provided that a general anaesthetic is necessary. However, some additional comments should be made.
The insertion of a nasogastric tube may be unnecessary in colonic surgery, provided there is no obstruction. It may be a surgical tradition without scientific basis, as suggested by Kehlet . In addition, the insertion under direct vision with Magill's forceps needs the aid of a laryngoscope that can produce laryngeal or epiglottic damage or oedema due to the continuous traction until insertion is achieved. The damage can be worse if laryngoscopy is difficult, which may be the case in an obese professional opera singer.
The use of nitrous oxide is at least controversial. In addition to the Editor's note on accumulation in the cuff of the endotracheal tube, the nitrous oxide can accumulate in the middle ear, thereby affecting the auditory abilities of the singer and thus, indirectly, the vocal performance. However, this should only be a temporary effect.
The surgical procedure referred to in the letter, i.e. a colonic cancer resection, may be carried out using epidural anaesthesia with sedation, thus avoiding the vocal cord damage associated with tracheal intubation. An epidural catheter inserted at a low or mid-thoracic level provides an adequate sensory blockade, making surgery feasible with a low risk in experienced hands . This can be obtained with bupivacaine 0.5%, mepivacaine 2% or ropivacaine 0.75-1% in sufficient dose (i.e. administered in 5 mL boluses). In my experience, the only intraoperative procedure that should be closely followed by asking the surgeons frequently is exploration and/or biopsy of the liver. This procedure usually involves touching the liver and the diaphragm that are not anaesthetized. This period, which is normally brief, can be covered by increasing the sedation or adding analgesic drugs intravenously. I use a midazolam infusion, with or without fentanyl, or low-dose ketamine.
The epidural may need to be combined with a light general anaesthetic. However, in the professional singer, this removes the special advantage of employing a regional block. Although still controversial, other advantages can be obtained from epidural anaesthesia and analgesia , e.g. a pre-emptive analgesic effect  or a faster postoperative recovery [2,6].
Detailed discussion with the patient is mandatory; the possible complications must be explained. Thus, the choices we have in our anaesthetic armamentarium permit the best choice to be made for a specific patient balancing the risk-benefit relationship.
C. L. Errando
Servicio de Anestesiología, Reanimación y Tratamiento del Dolor Hospital General Universitario de Valencia Valencia, Spain
1. Bullough A, Craig R. Anaesthesia for the professional singer. Eur J Anaesthesiol
2. Kehlet H. Multimodal approach to control postoperative pathophysiology and rehabilitation. Br J Anaesth
3. Giebler RM, Scherer RU, Peters J. Incidence of neurologic complications related to thoracic epidural catheterization. Anesthesiology
4. De Leon-Casasola OA, Lema MJ. Postoperative epidural opioid analgesia: what are the choices? Anesthesiology
5. Kissin I. Preemptive analgesia. Anesthesiology
6. Steinbrock RA. Epidural anesthesia and gastrointestinal motility. Anesth Analg