Diazepam premedication in ophthalmic surgery.

Diazepam (Valium), which meets most of the above requirements extremely well, is a tranquillizer of the benzodiazepine class, causing muscle relaxation and reduction of skeletal muscle tone (Ranidall, Heise, Schallek, Bagdon, Banziger, Boris, Mol, and Abrams, I96I). This action appears to be mediated through the central nervous system, for it can be shown that the stimulation of muscle through the motor nerve is unaffected. Animal experiments have shown that the respiratory centre and blood pressure are not affected (Parkes, I967). The pharmacological action ofreducing the muscle tone isveryadvantageous in ophthalmic surgery, since reduction in extraocular muscle tone lowers the intraocular pressure (Colle, Duke-Elder, and Duke-Elder, I93 i). Bruha (I964) measured the intraocular pressure in a series of patients before and after the administration of Diazepam, and in most cases in which the pressure was raised, there was a reduction to normal. Similar results were reported by Campan and Espagno (I966).