Correspondence
297
Flunitrazepam in dental outpatients We were most interested to read the letter from Dr Rollason (Anaesthesia, 1975, 30, 692) on the use of flunitrazepam in which he suggests that, although the agent is unsuitable for induction of general anaesthesia in dental outpatients, it may have a place as a sedative agent in conservative work. We have found that 1 mg of flunitrazepam administered intravenously produces a sedative effect similar to that following 20 mg of diazepam and induces a dense anterograde amnesia during the 10 minutes immediately following injection. This drug is, therefore, very similar to diazepam but has the advantage that it can be diluted and carries a much lower incidence of thrombophlebitis following its use. Studies carried out on patients with heart disease undergoing cardiac catheterisation have demonstrated a relatively mild effect upon cardiovascular function. These patients, with a variety of cardiac disorders, received between 0.01 and 0.02 mg/kg intravenously of a solution in which 1 mg of flunitrazepam was diluted to 4 ml and administered at the rate of 1 ml per minute. The observed cardiovascular changes were as follows:
% change Systolic pressure Diastolic pressure Pulse rate Cardiac output
- 13.0 - 8.3 -2.4 - 17.7
Standard deviation 0.08
0.07 0.09 17.3
n=8
Some 40 dental outpatients have received flunitrazepam for sedation to enable conservation work to be carried out. Cardiovascular and respiratory responses have been studied in detail and this work suggests that flunitrazepam may have a valuable role in the alleviation of anxiety in these patients. Department of Anaesthetics, Unisersity of Shefield Medical School, Beech Hill Road, Shefield, S10 2RX
J. A. THORNTON V. C. MARTIN
Atropine premedication in outpatient dentistry In the various published reports of vasovagal attacks and deaths during dental anaesthesia there has been little or no mention of the use of atropine as routine premedication prior to the induction of anaesthesia. It is the standard practice of many anaesthetists to give at least atropine prior to anaesthesia for all short non-dental operations, and one of the reasons for this is to prevent undue vagal stimulation. If operators are anxious, as well they should be, about excessive vagal stimulation during such procedures as forceful anal dilatation then they should also be concerned about the effects of vagal stimulation during dental extraction under light anaesthesia. The reason why dental outpatients seldom receive atropine may be that compassionate anaesthetists are anxious to spare their patients undue suffering or inconvenience but, surely, to dissociate dental anaesthesia from that given for other operations on grounds such as these is not being objective. Bearing in mind themortality and morbidity of dental anaesthesia in out-patients, particularly those who are anaesthetised with halothane in the sitting position
297
Flunitrazepam in dental outpatients We were most interested to read the letter from Dr Rollason (Anaesthesia, 1975, 30, 692) on the use of flunitrazepam in which he suggests that, although the agent is unsuitable for induction of general anaesthesia in dental outpatients, it may have a place as a sedative agent in conservative work. We have found that 1 mg of flunitrazepam administered intravenously produces a sedative effect similar to that following 20 mg of diazepam and induces a dense anterograde amnesia during the 10 minutes immediately following injection. This drug is, therefore, very similar to diazepam but has the advantage that it can be diluted and carries a much lower incidence of thrombophlebitis following its use. Studies carried out on patients with heart disease undergoing cardiac catheterisation have demonstrated a relatively mild effect upon cardiovascular function. These patients, with a variety of cardiac disorders, received between 0.01 and 0.02 mg/kg intravenously of a solution in which 1 mg of flunitrazepam was diluted to 4 ml and administered at the rate of 1 ml per minute. The observed cardiovascular changes were as follows:
% change Systolic pressure Diastolic pressure Pulse rate Cardiac output
- 13.0 - 8.3 -2.4 - 17.7
Standard deviation 0.08
0.07 0.09 17.3
n=8
Some 40 dental outpatients have received flunitrazepam for sedation to enable conservation work to be carried out. Cardiovascular and respiratory responses have been studied in detail and this work suggests that flunitrazepam may have a valuable role in the alleviation of anxiety in these patients. Department of Anaesthetics, Unisersity of Shefield Medical School, Beech Hill Road, Shefield, S10 2RX
J. A. THORNTON V. C. MARTIN
Atropine premedication in outpatient dentistry In the various published reports of vasovagal attacks and deaths during dental anaesthesia there has been little or no mention of the use of atropine as routine premedication prior to the induction of anaesthesia. It is the standard practice of many anaesthetists to give at least atropine prior to anaesthesia for all short non-dental operations, and one of the reasons for this is to prevent undue vagal stimulation. If operators are anxious, as well they should be, about excessive vagal stimulation during such procedures as forceful anal dilatation then they should also be concerned about the effects of vagal stimulation during dental extraction under light anaesthesia. The reason why dental outpatients seldom receive atropine may be that compassionate anaesthetists are anxious to spare their patients undue suffering or inconvenience but, surely, to dissociate dental anaesthesia from that given for other operations on grounds such as these is not being objective. Bearing in mind themortality and morbidity of dental anaesthesia in out-patients, particularly those who are anaesthetised with halothane in the sitting position
