670
Journal of the Royal Society of Medicine Volume 83 October 1990
Seizure induction by alcohol in epileptic patients With reference to the article by Heckmatt et al. (January 1990 JRSM, p 6) and the following letter by N Davis (May 1990 JRSM, p 342), I am rather surprised that no mention was made of hypoglycaemic convulsions in alcohol withdrawal. In 1979/80, while training my team of nurses in the techniques of neuroelectric therapy (NET) for detoxification in drug and alcohol addictions, a young alcoholic man with no previous history of epilepsy and, to our knowledge, not using any other psychoactive drugs, suffered hypoglycaemic convulsions. Thereafter, the nurses carried out a plastic strip test for blood sugar in all alcoholic patients with symptoms suggestive of hypoglycaemia, and we believe we prevented several such events by the timely administration of oral glucose or 50% dextrose intravenously depending on the level of the blood sugar. Consultant in NET MARGARET A PATTERSON 104 Harley Street, London WlN 1AF
Post TURP syndrome I read with interest Dr Hamilton's paper on Post TURP Syndrome (December 1989 JRSM, p 725); two points I would like to comment on. Firstly, Dr Hamilton advised the routine use of frusemide to prevent ADH secretion; this is hardly the case as this is a response to trauma and frusemide only treat the consequent fluid retention1' 2. Secondly, if a diuretic is needed why not use mannitol which gives the same result with less Na+ and Cl- loss in urine (unlike frusemide which acts by preventing Na+ and Cl- reabsorption in renal tabules), is not nephrotoxic (unlike frusemide) and has the theoretical advantage of maintaining plasma osmolality (being hypertonic)2 3. Frusemide does have a role where there is gross fluid overload and/or sign of pulmonary oedema: we have almost abandoned the use of frusemide in favour of mannitol during TURP. M ELIAS Consultant Anaesthetist St James's Hospital PO Box 580, Dublin 8 Ireland
References 1 Deacux G, Watelot V. SIADH - Treated with frusemide. BMJ 1982;285:85 2 Noreen F. Crucial and practical aspect in therapy of
hyponatremia. Int Crit Care Digest 1989;8:35 3 Pierce JM. Treatment of water intoxication following
TURP. J Urol 1962;87:181
The author replies below: On the first point I agree with him that intravenous frusemide following TURP treats the absorbed irrigation fluid retention which may not be excreted because of inappropriate ADH secretion, induced by major surgery. The article should have read 'parenteral frusemide to prevent the effects of inappropriate ADH secretion'. The rationale behind giving routine parenteral frusemide towards the end of a TURP is to induce an hypotonic diuresis while preventing sodium loss by administration of intravenous saline. In fact I do not use routine frusemide but thought its administration should be mentioned under discussion.
I disagree on his second point. The problem with mannitol infusion is that the hyponatraemia in the acute situation is worsened if there is not prompt diuresis. In the case of profound hyponatraemia a patient suffering TURP syndrome could be pushed into status epilepticus by a sudden infusion of an hypoelectrolyte solution such as mannitol. Worsening ofthe hyponatraemia could also produce ECG changes. P A HAMITON STEWART Consultant Urological Surgeon Bradford Royal Infirmary Duckworth Lane Bradford BD9 6RJ
Health effects of electromagnetic fields In his editorial (February 1990 JRSM, p 63) Cox makes several statements that must be challenged. Firstly, he assumes that the benefits of electricity are, a priori, consistent with safety! This reminds one of an earlier strongly held belief that retroviruses did not occur in man, and that viruses did not cause cancer. In the last 10 years both of these beliefs have been proven dead wrong1. While I am not suggesting the same dramatic effect for electromagnetic fields, to blindly accept the concept of safety, in view of the ever increasing evidence to the contrary, is both unscientific as well as foolhardy. Secondly, Cox states that the public is persuaded by what he assumes are 'quasi-scientific work unsupported by acceptable scientific evidence'. To discount the results from the laboratories of Drs R Adey in California, R Goodman in New York and J Leal in Madrid, to name only a few, suggests either a lack of knowledge of the field and the work in progress, or a bias on the subject. Finally, Cox states that the field strengths used are generally orders of magnitude greater than those implicated by epidemiological findings. This statement is incorrect. Since 1979, the majority of basic science experiments have utilized field strengths in the range that one might encounter in our everyday environment (0.01-30 uT)2. In fact the concern, especially among physical scientists, has not been that the fields were too strong but rather that they were lower than allowed by thermal noise. This thermal noise limit, while fundamental, is also important because other biological response mechanisms have thresholds close to this limit3. I agree with the statement by Cox that 'if emfs are shown to have health effects in adults, at the levels postulated by Savitz of about 2 mG4, then there could be significant public health effects because of the ubiquity of the fields'. The problem however may be more critical for the developing fetus, which is known to react to teratological agents at levels well below those which adversely affect the adult. A H MARTIN Professor of Anatomy The University of Western Ontario London, Ontario, Canada
Reference 1 Gallo, RC. Discovering the human retrovirus. Curr Contents/Life Science 1990;33:16 2 Duchene AS. Interim guidelines on limiJ of exposure to 50/60 Hz electric and magnetic fields. Health Phys 1990;1:113-22 3 Weaver JC, Astumian RD. The response of living cells to very weak electric fields: the thermal noise limit. .
Science 1990;247:459-62 4 Savitz D. Case control study of childhood cancer and exposure to 60 Hz magnetic fields. Am J Epidemiol
1988;14:337-43
Journal of the Royal Society of Medicine Volume 83 October 1990
Seizure induction by alcohol in epileptic patients With reference to the article by Heckmatt et al. (January 1990 JRSM, p 6) and the following letter by N Davis (May 1990 JRSM, p 342), I am rather surprised that no mention was made of hypoglycaemic convulsions in alcohol withdrawal. In 1979/80, while training my team of nurses in the techniques of neuroelectric therapy (NET) for detoxification in drug and alcohol addictions, a young alcoholic man with no previous history of epilepsy and, to our knowledge, not using any other psychoactive drugs, suffered hypoglycaemic convulsions. Thereafter, the nurses carried out a plastic strip test for blood sugar in all alcoholic patients with symptoms suggestive of hypoglycaemia, and we believe we prevented several such events by the timely administration of oral glucose or 50% dextrose intravenously depending on the level of the blood sugar. Consultant in NET MARGARET A PATTERSON 104 Harley Street, London WlN 1AF
Post TURP syndrome I read with interest Dr Hamilton's paper on Post TURP Syndrome (December 1989 JRSM, p 725); two points I would like to comment on. Firstly, Dr Hamilton advised the routine use of frusemide to prevent ADH secretion; this is hardly the case as this is a response to trauma and frusemide only treat the consequent fluid retention1' 2. Secondly, if a diuretic is needed why not use mannitol which gives the same result with less Na+ and Cl- loss in urine (unlike frusemide which acts by preventing Na+ and Cl- reabsorption in renal tabules), is not nephrotoxic (unlike frusemide) and has the theoretical advantage of maintaining plasma osmolality (being hypertonic)2 3. Frusemide does have a role where there is gross fluid overload and/or sign of pulmonary oedema: we have almost abandoned the use of frusemide in favour of mannitol during TURP. M ELIAS Consultant Anaesthetist St James's Hospital PO Box 580, Dublin 8 Ireland
References 1 Deacux G, Watelot V. SIADH - Treated with frusemide. BMJ 1982;285:85 2 Noreen F. Crucial and practical aspect in therapy of
hyponatremia. Int Crit Care Digest 1989;8:35 3 Pierce JM. Treatment of water intoxication following
TURP. J Urol 1962;87:181
The author replies below: On the first point I agree with him that intravenous frusemide following TURP treats the absorbed irrigation fluid retention which may not be excreted because of inappropriate ADH secretion, induced by major surgery. The article should have read 'parenteral frusemide to prevent the effects of inappropriate ADH secretion'. The rationale behind giving routine parenteral frusemide towards the end of a TURP is to induce an hypotonic diuresis while preventing sodium loss by administration of intravenous saline. In fact I do not use routine frusemide but thought its administration should be mentioned under discussion.
I disagree on his second point. The problem with mannitol infusion is that the hyponatraemia in the acute situation is worsened if there is not prompt diuresis. In the case of profound hyponatraemia a patient suffering TURP syndrome could be pushed into status epilepticus by a sudden infusion of an hypoelectrolyte solution such as mannitol. Worsening ofthe hyponatraemia could also produce ECG changes. P A HAMITON STEWART Consultant Urological Surgeon Bradford Royal Infirmary Duckworth Lane Bradford BD9 6RJ
Health effects of electromagnetic fields In his editorial (February 1990 JRSM, p 63) Cox makes several statements that must be challenged. Firstly, he assumes that the benefits of electricity are, a priori, consistent with safety! This reminds one of an earlier strongly held belief that retroviruses did not occur in man, and that viruses did not cause cancer. In the last 10 years both of these beliefs have been proven dead wrong1. While I am not suggesting the same dramatic effect for electromagnetic fields, to blindly accept the concept of safety, in view of the ever increasing evidence to the contrary, is both unscientific as well as foolhardy. Secondly, Cox states that the public is persuaded by what he assumes are 'quasi-scientific work unsupported by acceptable scientific evidence'. To discount the results from the laboratories of Drs R Adey in California, R Goodman in New York and J Leal in Madrid, to name only a few, suggests either a lack of knowledge of the field and the work in progress, or a bias on the subject. Finally, Cox states that the field strengths used are generally orders of magnitude greater than those implicated by epidemiological findings. This statement is incorrect. Since 1979, the majority of basic science experiments have utilized field strengths in the range that one might encounter in our everyday environment (0.01-30 uT)2. In fact the concern, especially among physical scientists, has not been that the fields were too strong but rather that they were lower than allowed by thermal noise. This thermal noise limit, while fundamental, is also important because other biological response mechanisms have thresholds close to this limit3. I agree with the statement by Cox that 'if emfs are shown to have health effects in adults, at the levels postulated by Savitz of about 2 mG4, then there could be significant public health effects because of the ubiquity of the fields'. The problem however may be more critical for the developing fetus, which is known to react to teratological agents at levels well below those which adversely affect the adult. A H MARTIN Professor of Anatomy The University of Western Ontario London, Ontario, Canada
Reference 1 Gallo, RC. Discovering the human retrovirus. Curr Contents/Life Science 1990;33:16 2 Duchene AS. Interim guidelines on limiJ of exposure to 50/60 Hz electric and magnetic fields. Health Phys 1990;1:113-22 3 Weaver JC, Astumian RD. The response of living cells to very weak electric fields: the thermal noise limit. .
Science 1990;247:459-62 4 Savitz D. Case control study of childhood cancer and exposure to 60 Hz magnetic fields. Am J Epidemiol
1988;14:337-43
