Medical Pharmacology Chapter 12:  Anxiolytics and Sedative-Hypnotics

• Proton pump inhibitors:

  • Overview:

    • Parietal cells H⁺ ion secretion depends on a H⁺,K⁺-ATPase pump, promoting H⁺ K⁺ exchange.

      • H+, K+-ATPase located in apical membrane and tubulovesicular apparatus of parietal cells.

      • Luminal surface of the membrane enzyme: exposed to gastric luminal acid.

  • Specific drugs:

    • Omeprazole (Prilosec)

      • Dosage (adult):

        • Intravenous dosage is 40 mg administered 30 minutes prior to induction.

        • The oral dose range is between 40 and 80 mg administered between 2 and 4 hours before the procedure.

      • Mechanism of action: Omeprazole (Prilosec) and lansoprazole (Prevacid) bind "irreversibly" to the proton pump. 

        • This action result in an extended duration of action, since new protein must be synthesized to reestablish proton secretion function.

      • Duration of action: The effect on gastric pH may be as long as 24 hours with variable effects on gastric volume (omeprazole (Prilosec)).

 

 

References

• ¹Preoperative Medication in Basis of Anesthesia, 4th Edition, Stoelting, R.K. and Miller, R., p 119- 130, 2000) 

• Hobbs, W.R, Rall, T.W., and Verdoorn, T.A., Hypnotics and Sedatives; Ethanol In, Goodman and Gillman's The Pharmacologial Basis of Therapeutics,(Hardman, J.G, Limbird, L.E, Molinoff, P.B., Ruddon, R.W, and Gilman, A.G.,eds) TheMcGraw-Hill Companies, Inc., 1996, pp. 364-367.

• ³Sno E. White The Preoperative Visit and Premedication in Clinical Anesthesia Practice pp.  576-583 (Robert Kirby & Nikolaus Gravenstein, eds) W.B.  Saunders Co., Philadelphia, 1994

• ⁴John R. Moyers and Carla M. Vincent Preoperative Medication in Clinical Anethesia, 4th edition (Paul G. Barash, Bruce. F. Cullen, Robert K. Stoelting, eds) Lippincott Williams & Wilkins, Philadelphia, PA, pp 551-565, 2001

• ⁵Michael Ross and Susan Dufel "Torticollis" emedicine, http://www.emedicine.com/emerg/topic597.htm