Upper oesophageal sphincter pressure during inhalational anaesthesia

Upper oesophageal sphincter pressure was recorded with a Dent sleeve in 30 patients breathing nitrous oxide, oxygen and halothune. Twenty‐three patients, after thiopentone induction, received suxamethonium and had their trachea intubated either before (group A, n = 11), or after (group B,n = 11), a study period of inhalational anaesthesia. Group C (n = 8 j received an inhalational induction. Mean (SD) sphincter pressure after loss of consciousness was 8 (7) mmHg (group A), 6 (5) mmHg (group B) and 24 (13) mmHg (group C) increasing to 79 (7) mmHg in group A immediately after intubation. With an end‐tidal halothane concentration of 1.5%, mean sphincter pressure in group B, 16 (7) mmHg, was significantly lower than in group A, 45 (21) mmHg (p < 0.001 J and group C, 27 (14) mmHg (p < 0.05). Halothane had no dose‐related effect on sphincter pressure. Insertion of a laryngeal mask in group C (n = 7) had no significant effect on sphincter pressure. Induction and maintenance of anaesthesia with halothane, unlike thiopentone or suxamethonium, maintained a degree of upper oesophageal sphincter tone, although three patients in this study had sphincter pressures of less than 10 mmHg and would therefore have been at risk of regurgitation in the presence of gastro‐oesophageal reflux.

[1]  R. Vanner.  Gastro-oesophageal reflux and regurgitation during general anaesthesia for termination of pregnancy. , 1992, International journal of obstetric anesthesia.

[2]  J. O'Dwyer,et al.  Upper oesophageal sphincter pressure and the intravenous induction of anaesthesia , 1992, Anaesthesia.

[3]  J. O'Dwyer,et al.  Upper oesophageal sphincter pressure and the effect of cricoid pressure , 1992, Anaesthesia.

[4]  J. Dent,et al.  Monitoring of upper oesophageal sphincter pressure in children. , 1991, Gut.

[5]  J. Dent,et al.  Measurement of upper esophageal sphincter pressure. Effect of acute emotional stress. , 1987, Gastroenterology.

[6]  J. Dent,et al.  Effect of sleep, spontaneous gastroesophageal reflux, and a meal on upper esophageal sphincter pressure in normal human volunteers. , 1987, Gastroenterology.

[7]  T. Nishino,et al.  Responses of Recurrent Laryngeal, Hypoglossal, and Phrenic Nerves to Increasing Depths of Anesthesia with Halothane or Enflurane in Vagotomized Cats , 1985, Anesthesiology.

[8]  J. Steen,et al.  Tracheal tube forces on the posterior larynx: index of laryngeal loading. , 1982, Critical care medicine.

[9]  J. Dent,et al.  Mechanism of gastroesophageal reflux in recumbent asymptomatic human subjects. , 1980, The Journal of clinical investigation.

[10]  E. Palmer.  Disorders of the cricopharyngeus muscle: a review. , 1976, Gastroenterology.

[11]  C. Blitt,et al.  “Silent” Regurgitation and Aspiration During General Anesthesia , 1970, Anesthesia and analgesia.

[12]  D. Cour.  PREVENTION OF RISE IN INTRAGASTRIC PRESSURE DUE TO SUXAMETHONIUM FASCICULATIONS BY PRIOR DOSE OF D‐TUBOCURARINE , 1970 .

[13]  D. la Cour.  Prevention of rise in intragastric pressure due to suxamethonium fasciculations by prior dose of d-tubocurarine. , 1970, Acta Anaesthesiologica Scandinavica.

[14]  E. O'mullane.  Vomiting and regurgitation during anesthesia. , 1954, International journal of anesthesia.

[15]  E. O'mullane.  Vomiting and regurgitation during anaesthesia. , 1954, Lancet.