242
Correspondence
Macewen antedated ?
I read with great interest the paper by Dr C. D. T. James on Sir William Macewen and Anaesthesia (Anaesthesia, 1974, 29, 743). I do feel however that Macewen’s work on intubation of the larynx instead of tracheostomy in cases of diptheria was a logical continuation of earlier work. Dr M. Bouchut of Paris twenty years previously described the use of a 1.5 to 2 cm long silver tube passed on an introducer through the mouth and into the larynx. It was held in position by having two rims close to one another at the upper end of the tube, one fitting above and the other below the true cords. The tube could be removed by pulling a silk thread attached to one of the rims (Half Yearly Abstract of Medical Science, (1858) 28, 91 and (1859) 29,42). It is interesting to note that the Parisian Academy of Medicine condemned this treatment. It must also be presumed other workers were intubating the larynx as Dr Luzinsky of Vienna is quoted as preferring to catheterise the trachea rather than tracheostomy (Half Yearly Abstract of Medical Science (1859) 29, 43). Mount Vernon Hospital, Northwood, Middlesex
I. MCLELLAN
Arms and the Anaesthetist May I, as a junior member of the Association not unversed in the science of Heraldry comment on D r D. V. Thomas’s letter (Anaesthesia, 1974, 29, 627) regarding the badge (!!!) of the Association ? Our heraldic achievement is one of the most illuminating examples of modern day heraldic use which is characterised by simplicity and lack of fussy features. Even the most ignorant must immediately realise the nature of the organisation from our coat of arms. Quite apart from the fact that, as you so rightly stated, arms once granted cannot be changed, although of course they can be augmented, I doubt whether a better coat of arms obeying all the very stringent rules of heraldry could be created. As you pointed out it is a very great honour for a corporate body to have a grant of arms, bestowed upon it by the Sovereign through His or Her Officers of Arms. It is a very important ‘stat’us symbol’. Department of Anaesthetics, University Hospital of Wales, Heath Park, Cardifs CF4 4XN, Wales
CHARLES A. GAUCI
Anaesthesia for coarctation I read with interest the article by F. Y . Dalal and his colleagues in the November issue (Anaesthesia, 1974, 29, 704). May I add a few comments? It is always worthwhile monitoring the Central Venous Pressure (CVP) during this, or indeed any other, major procedure whether cardio-thoracic or otherwise, particularly where there is danger of sudden massive blood loss. I also believe that direct arterial pressure monitoring by cannulation of the right radial artery is another essential during the repair of coarctation of the aorta. The arterial pressure can thus be read either from an oscilloscope or, if this is not available, with the aid of the ‘bubble technique’. The bubble will also allow constant monitoring of pulse rate and rhythm and arterial blood gas analysis is also facilitated. It is, indeed, my opinion that direct arterial pressure monitoring should be routinely used in all types of major surgery.
Correspondence
243
A ‘microdrip’ of Arfonad (trimetaphan) 0.1z-O.2% produces very smooth hypotension and can safely be continued into the post-operative period if hypertension is a problem. Should the blood pressure fall below the desired level during the operation (80 mm Hg systolic) an alpha-sympathetic agent, e.g. methoxamine, may be used (1-2 mg or more intravenously as necessary). Acidosis from clamping is an unlikely complication in the vast majority of cases, since there is an appropriately developed collateral circulation. In my personal experience, the most important hazard during surgery for coarctation is severe and unexpected haemorrhage, often from a major artery arising behind the aorta. There is no doubt that the present surgical method of internal mammary or Dacron patching, rather than excision of the constriction has greatly simplified the operation, and eliminated the problems and dangers of ‘end to end’ anastomosis. National Heart Hospital, Westmoreland Street, London W I M 8BA
ALANGILSTON
Reference 1. GILSTON, A. (1972) The arterial blood pressure. British Journal of Anaesthesia, 44,1334.
A reply
My colleagues and I concur wholeheartedly with Dr Gilston’s suggestion that CVP is worthwhile monitoring in major surgical procedure but we believe that direct arterial pressure monitoring, though desirable, is not mandatory unless indirect methods are unsatisfactory, for example in infants. In a previous article by two of us, we mentioned that blood pressure was monitored by an indwelling catheter in patients under 1 year (Anaesthesia, 1974,29,269). The rationale for having blood pressure cuffs on both arms is the possibility that occlusion of the left subclavian artery may occur accompanied by the disappearance of the pulse in the left arm, and the possibility of par?ial or complete obstruction of the right axilliary artery due to compression in the left lateral position. We have two reservations regarding the use of Arfonad (trimetaphan) as the hypotensive agent of choice: firstly tachyphylaxis is a well known phenomenon with this drug and, secondly we are not sure if it will control the delayed postoperative hypertension and the risk of a mesenteric vasculitis associated with it. In the previous article, we have shown the rarity of this complication when the hypotension was induced with pentolinium tartrate. It would be interesting to find out if hypotensive technique was used in the hospitals where the surgical correction of the defect was the present surgical method of internal mammary, or dacron patching rather than excision of the constriction. We believe that a hypotensive technique, besides reducing the blood loss, helps the surgeon significantly by having a ‘lax’ aorta so that mobilization can be achieved without the fear of a tear. If the facilities for the measuring of blood gases are available, it would be rational to withhold the injection of sodium bicarbonate routinely prior to the release of the aortic clamp. Howe&r, when the blood gases are not measured, it could be a wise precaution to inject it prior to release as all patients with coarctation of the aorta do not have well developed collateral circulation. Loyola University, Stritch School of Medicine, 2106, S . First Avenue, Marywood, lllinois 601 53, U.S.A.
F. Y . DALAL
Correspondence
Macewen antedated ?
I read with great interest the paper by Dr C. D. T. James on Sir William Macewen and Anaesthesia (Anaesthesia, 1974, 29, 743). I do feel however that Macewen’s work on intubation of the larynx instead of tracheostomy in cases of diptheria was a logical continuation of earlier work. Dr M. Bouchut of Paris twenty years previously described the use of a 1.5 to 2 cm long silver tube passed on an introducer through the mouth and into the larynx. It was held in position by having two rims close to one another at the upper end of the tube, one fitting above and the other below the true cords. The tube could be removed by pulling a silk thread attached to one of the rims (Half Yearly Abstract of Medical Science, (1858) 28, 91 and (1859) 29,42). It is interesting to note that the Parisian Academy of Medicine condemned this treatment. It must also be presumed other workers were intubating the larynx as Dr Luzinsky of Vienna is quoted as preferring to catheterise the trachea rather than tracheostomy (Half Yearly Abstract of Medical Science (1859) 29, 43). Mount Vernon Hospital, Northwood, Middlesex
I. MCLELLAN
Arms and the Anaesthetist May I, as a junior member of the Association not unversed in the science of Heraldry comment on D r D. V. Thomas’s letter (Anaesthesia, 1974, 29, 627) regarding the badge (!!!) of the Association ? Our heraldic achievement is one of the most illuminating examples of modern day heraldic use which is characterised by simplicity and lack of fussy features. Even the most ignorant must immediately realise the nature of the organisation from our coat of arms. Quite apart from the fact that, as you so rightly stated, arms once granted cannot be changed, although of course they can be augmented, I doubt whether a better coat of arms obeying all the very stringent rules of heraldry could be created. As you pointed out it is a very great honour for a corporate body to have a grant of arms, bestowed upon it by the Sovereign through His or Her Officers of Arms. It is a very important ‘stat’us symbol’. Department of Anaesthetics, University Hospital of Wales, Heath Park, Cardifs CF4 4XN, Wales
CHARLES A. GAUCI
Anaesthesia for coarctation I read with interest the article by F. Y . Dalal and his colleagues in the November issue (Anaesthesia, 1974, 29, 704). May I add a few comments? It is always worthwhile monitoring the Central Venous Pressure (CVP) during this, or indeed any other, major procedure whether cardio-thoracic or otherwise, particularly where there is danger of sudden massive blood loss. I also believe that direct arterial pressure monitoring by cannulation of the right radial artery is another essential during the repair of coarctation of the aorta. The arterial pressure can thus be read either from an oscilloscope or, if this is not available, with the aid of the ‘bubble technique’. The bubble will also allow constant monitoring of pulse rate and rhythm and arterial blood gas analysis is also facilitated. It is, indeed, my opinion that direct arterial pressure monitoring should be routinely used in all types of major surgery.
Correspondence
243
A ‘microdrip’ of Arfonad (trimetaphan) 0.1z-O.2% produces very smooth hypotension and can safely be continued into the post-operative period if hypertension is a problem. Should the blood pressure fall below the desired level during the operation (80 mm Hg systolic) an alpha-sympathetic agent, e.g. methoxamine, may be used (1-2 mg or more intravenously as necessary). Acidosis from clamping is an unlikely complication in the vast majority of cases, since there is an appropriately developed collateral circulation. In my personal experience, the most important hazard during surgery for coarctation is severe and unexpected haemorrhage, often from a major artery arising behind the aorta. There is no doubt that the present surgical method of internal mammary or Dacron patching, rather than excision of the constriction has greatly simplified the operation, and eliminated the problems and dangers of ‘end to end’ anastomosis. National Heart Hospital, Westmoreland Street, London W I M 8BA
ALANGILSTON
Reference 1. GILSTON, A. (1972) The arterial blood pressure. British Journal of Anaesthesia, 44,1334.
A reply
My colleagues and I concur wholeheartedly with Dr Gilston’s suggestion that CVP is worthwhile monitoring in major surgical procedure but we believe that direct arterial pressure monitoring, though desirable, is not mandatory unless indirect methods are unsatisfactory, for example in infants. In a previous article by two of us, we mentioned that blood pressure was monitored by an indwelling catheter in patients under 1 year (Anaesthesia, 1974,29,269). The rationale for having blood pressure cuffs on both arms is the possibility that occlusion of the left subclavian artery may occur accompanied by the disappearance of the pulse in the left arm, and the possibility of par?ial or complete obstruction of the right axilliary artery due to compression in the left lateral position. We have two reservations regarding the use of Arfonad (trimetaphan) as the hypotensive agent of choice: firstly tachyphylaxis is a well known phenomenon with this drug and, secondly we are not sure if it will control the delayed postoperative hypertension and the risk of a mesenteric vasculitis associated with it. In the previous article, we have shown the rarity of this complication when the hypotension was induced with pentolinium tartrate. It would be interesting to find out if hypotensive technique was used in the hospitals where the surgical correction of the defect was the present surgical method of internal mammary, or dacron patching rather than excision of the constriction. We believe that a hypotensive technique, besides reducing the blood loss, helps the surgeon significantly by having a ‘lax’ aorta so that mobilization can be achieved without the fear of a tear. If the facilities for the measuring of blood gases are available, it would be rational to withhold the injection of sodium bicarbonate routinely prior to the release of the aortic clamp. Howe&r, when the blood gases are not measured, it could be a wise precaution to inject it prior to release as all patients with coarctation of the aorta do not have well developed collateral circulation. Loyola University, Stritch School of Medicine, 2106, S . First Avenue, Marywood, lllinois 601 53, U.S.A.
F. Y . DALAL
