Annotations Table I. C o r r e l a t i o n c o e f f i c i e n t s a n d r e g r e s s i o n e q u a t i o n s End-systolic volume index End-diastolic volume index Stroke volume index Ejection fraction
r r r r
= = = =
0.986 0.981 0.988 0.980
Table II
End-diastolicvolume
Proposed method
Dodge,Kasser and Kennedy
Mean ] S.D.
Mean I S.D.
21.2
•
70.6 49.6
8
21
___ 8
• 17
70.4
-+ 16
_ 16
49.4
-+ 15
S.E.E. S.E.EI S.E.E. S.E.E.
= = = =
0.68
•
0.11
0.66
•
= = = =
0.9569 0.9412 0.9459 0.9290
x x x x
+ + + +
0.6792 3.57 2.57 5.21
Eduardo Meaney Jacques St-Pierre Ralph Shabetai Andrd Davignon Department of Pediatrics H6pital Ste-Justine Montrdal, Qudbec, Canada and Department of Medicine University of Kentucky College of Medicine Lexington, Ky.
0.15
actual linear dimension. The relation between this LCF and the CF utilized in the standard procedure is as follows: LCF = 4Ap/A~ = 1/CF (3) Equation I can be rewritten as: V = 0.84 9 Aa2/Lp 9 LCF (4) The results obtained by the two methods were analyzed and compared statistically (Tables I and II). Our simplified method gave results which correlated well with the more
Y Y Y Y
cumbersome classical methods. The proposed method eliminates the need for planimetry, a desk calculator, and pencil drawings of the projected outlines, and it is hoped that it may prove useful and time-saving in the routine cardiac catheterization laboratory.
(M1./M. 2) End-systolic volume (M1./M.0 Stroke volume (M1./MY) Ejection Fraction
_+1.33 _+ 3.35 • 2.39 • 0.02
REFERENCES 1.
Dodge, H. T., Sandler, H., BalleT, D. H., and Lord, J. D.: The use of biplane angiocardiography for the measurement of left ventricular volume in man, AM. HEART J. 60"762, 1960. 2. Kasser, I. S., and Kennedy, J. W.: Measurement of left ventricular volumes in man by single-plan~ cineangiography, Invest. Radiol. 18:2, 1966.
Prevention of deep-vein thrombosis
The large volume of literature published over the last two years on the subject of deep-vein thrombosis serves to illustrate how great is the just concern of the thinking medical world over this very worrying and potentially dangerous condition, but the etiologic diversities of the condition necessitate fundamental thinking in considering priorities for prevention of its occurrence. Thus, in the paraoperative period just how important is the actual surgery, performed in general terms, on the incidence of deep-vein thrombosis? Is it the trauma of the knife or the stretching of tissues t h a t one must consider? Does a rough operator produce higher figures than a gentler one? If it is tissue trauma, what is the relative incidence of deep-vein thrombosis in nonoperable trauma cases in intensive-care units? While not forgetting the much valuable contributory research work on the fibrinolytic system, and even the evidence that cases developing deep-vein thrombosis may be anticipated before surgery, 1 I believe that the occurrence figures throughout the world, as detected by the 1~5I-
400
fibrinogen method, vary too widely for the operation itself, again in general terms, to be of great importance. As I have suggested elsewhere,~ I believe the degree of blood flow in the deep veins of the leg to be the most important etiologic factor, and that the avoidance of hypovolemia is the primary consideration in the prevention of the thrombotic condition. Many anesthetists must begin to think in broader horizons for their patients, and even be prepared to modify their "standard" techniques considerably. It is easy to speak of position on the operating table, removal of skeletal muscle tone, sweating, direct pelvic surgical trauma, paraoperative vomiting, postoperative hypoventilation, and prolonged immobilization as being all of direct and vital importance, but it is the thinking standard of the anesthetist t h a t is of paramount importance. The normal human body can resist the sometime insults imposed on it by poor quality anesthesia, the end result being the same. However, one insult it cannot cope with is prolonged paraoperative reduction in deep-vein blood flow in the legs.
March, 1976, Vol. 91, No. 3
Annotations
In terms of hypovolemia, I believe t h a t m a n y anesthetists do not put up enough intravenous infusions (to cover paraoperative "normal" water requirements as well as blood), and d o not give enough fluid when the infusion is up. (How m a n y of your patients are thirsty after operation?) In some centers every patient has an intravenous drip put up before anesthesia begins. Somewhere between the two extremes probably is more satisfactory. We must all have seen patients for operation at midday who have had nothing to drink since late the previous evening, and who then on the operating table have to contend with further reduction in blood volume from bleeding and sweating. Surely a cup of tea and biscuit given not less t h a n four hours before premedication does no harm and can only help to stimulate blood flow? Looking further afield, could it be t h a t the published results following treatment for prevention of deep-vein thrombosis following cardiac infarction vary due to varying degrees of hydration? Are cases of venous thrombosis following strokes due to a fear of giving old people too much fluid? Do well controlled long-term unconscious patients in intensive-care units seem to show a relatively low incidence of leg deep-vein thrombosis because the central venous pressure is maintained more near normal? From other anesthetic aspects the prolonged recovery from anesthesia, with its accompanying immobilization and hypoventilation and recognized associated dangers, may produce a tranquil time for the patient, but is often due to an unnecessary "overdose" of anesthesia, or to incorrect timing in the giving of analgesics. In an operation where the patient is paralyzed and asleep, the anesthetist must largely concentrate on the likelihood of awareness and on the prevention of undue pain postoperatively. Of course, we want the patient preoperatively tranquil and postoperatively pain-free, but too much is too much. The likelihood of awareness, I believe, should be gauged on a mental estimation of the preoperative metabolic rate r a t h e r than body-weight per se. I have previously shown 3 t h a t the alteration in arterial Paco ~ following the same premedication (in Jamaica) shows an inverse linear relationship to metabolic rate as expressed as a percentage of normal. Thus a thinner, lighter, nervous individual may require more premedication and/or sleep agent than a fatter, heavier, b u t more tranquil one. This approach is supported by Claridge. 4 My experience further suggests t h a t patients in quiet, rural
"cottage" hospitals often need less narcotic agents t h a n those in busy city hospitals, as judged by sleep time following anesthesia. The routine giving of analgesics during anesthesia should also be carefully examined. When and why to give an agent is part of the unsung science of anesthesia. Is it for keeping the patient asleep by reducing sensory stimulus, to reduce adrenergic activity, or to anticipate an unknown postoperative pain status? Many schools of thought dislike adrenergic activity under anesthesia, but is it not better with a normal heart to permit some, thus allowing a better circulation to counteract a tendency to leg venous stasis and deep-vein thrombosis? Is it not also more "scientifiC" to assess pain as the patient awakes and to "titrate" the analgesic effect by small-dose intravenous analgesic injection? Thus, I believe, t h a t the modern anesthetist must think more broadly in terms of preserving a normal central venous pressure. Coupled with this he must ensure t h a t the preoperative patient is adequately sedated, but not oversedated {remember the accumulative night sedation effect); t h a t during the operation adrenergic activity in the normal patient should not be unduly suppressed; and t h a t postoperatively the patient should be quickly awake {after five minutes in recovery following a relaxant technique) with good muscle tone; and with postoperative pain tending to be treated by titration in the recovery room rather t h a n blindly on the oPerating table. These things, the avoidance of polypharmacy blindly given, and our physiotherapists, should be the greatest factors to concentrate on in the fight against deep-vein thrombosis.
J. Michael Simpson, M.B., B.S., F.F.A., R.C.S. St. Nicolaas Ziekenhuis Waalwijk, The Netherlands REFERENCES
1. Gallus, A. S., Hirsh, J., and Gent, M.: Relevance of preoperative and postoperative blood tests to postoperative leg-vein thrombosis, Lancet 2:805, 1973. 2. Simpson, J. M.: Fibrinolytic activity and postoperative deep-vein thrombosis, Lancet 1:352, 1974. {Letter to Eclitor). 3. Simpson, J. M.: Environmental temperature and reponse to premedicant drugs, Anaesthesia 25:508, 1970. 4. Claridge, G. S.: The relative influence of weight and of "nervous type" on the tolerance of a m y l o b a r b i t o n e sodium, Br. J. Anaes. 43:1121, 1971.
Of smoking and the respiratory tract
The publicity and propaganda t h a t smoking produces carcinoma of the lungs and heart disease have diverted the attention of all people from the more important fact that, even though these claims are true, the incidences of these illnesses are relatively minor when it is realized t h a t all (100 per cent) of the people who smoke have chronic diseases of their entire
American Heart Journal
respiratory tract. All smokers have chronic pharyngitis, chronic paranasal sinusitis, chronic laryngitis, chronic tracheitis, chronic bronchitis and bronchiectasis, and many are destined to have serious emphysema. Furthermore, acute respiratory tract infections are prone to develop upon these chronic diseases. Any physician who remembers or reviews the
401
r r r r
= = = =
0.986 0.981 0.988 0.980
Table II
End-diastolicvolume
Proposed method
Dodge,Kasser and Kennedy
Mean ] S.D.
Mean I S.D.
21.2
•
70.6 49.6
8
21
___ 8
• 17
70.4
-+ 16
_ 16
49.4
-+ 15
S.E.E. S.E.EI S.E.E. S.E.E.
= = = =
0.68
•
0.11
0.66
•
= = = =
0.9569 0.9412 0.9459 0.9290
x x x x
+ + + +
0.6792 3.57 2.57 5.21
Eduardo Meaney Jacques St-Pierre Ralph Shabetai Andrd Davignon Department of Pediatrics H6pital Ste-Justine Montrdal, Qudbec, Canada and Department of Medicine University of Kentucky College of Medicine Lexington, Ky.
0.15
actual linear dimension. The relation between this LCF and the CF utilized in the standard procedure is as follows: LCF = 4Ap/A~ = 1/CF (3) Equation I can be rewritten as: V = 0.84 9 Aa2/Lp 9 LCF (4) The results obtained by the two methods were analyzed and compared statistically (Tables I and II). Our simplified method gave results which correlated well with the more
Y Y Y Y
cumbersome classical methods. The proposed method eliminates the need for planimetry, a desk calculator, and pencil drawings of the projected outlines, and it is hoped that it may prove useful and time-saving in the routine cardiac catheterization laboratory.
(M1./M. 2) End-systolic volume (M1./M.0 Stroke volume (M1./MY) Ejection Fraction
_+1.33 _+ 3.35 • 2.39 • 0.02
REFERENCES 1.
Dodge, H. T., Sandler, H., BalleT, D. H., and Lord, J. D.: The use of biplane angiocardiography for the measurement of left ventricular volume in man, AM. HEART J. 60"762, 1960. 2. Kasser, I. S., and Kennedy, J. W.: Measurement of left ventricular volumes in man by single-plan~ cineangiography, Invest. Radiol. 18:2, 1966.
Prevention of deep-vein thrombosis
The large volume of literature published over the last two years on the subject of deep-vein thrombosis serves to illustrate how great is the just concern of the thinking medical world over this very worrying and potentially dangerous condition, but the etiologic diversities of the condition necessitate fundamental thinking in considering priorities for prevention of its occurrence. Thus, in the paraoperative period just how important is the actual surgery, performed in general terms, on the incidence of deep-vein thrombosis? Is it the trauma of the knife or the stretching of tissues t h a t one must consider? Does a rough operator produce higher figures than a gentler one? If it is tissue trauma, what is the relative incidence of deep-vein thrombosis in nonoperable trauma cases in intensive-care units? While not forgetting the much valuable contributory research work on the fibrinolytic system, and even the evidence that cases developing deep-vein thrombosis may be anticipated before surgery, 1 I believe that the occurrence figures throughout the world, as detected by the 1~5I-
400
fibrinogen method, vary too widely for the operation itself, again in general terms, to be of great importance. As I have suggested elsewhere,~ I believe the degree of blood flow in the deep veins of the leg to be the most important etiologic factor, and that the avoidance of hypovolemia is the primary consideration in the prevention of the thrombotic condition. Many anesthetists must begin to think in broader horizons for their patients, and even be prepared to modify their "standard" techniques considerably. It is easy to speak of position on the operating table, removal of skeletal muscle tone, sweating, direct pelvic surgical trauma, paraoperative vomiting, postoperative hypoventilation, and prolonged immobilization as being all of direct and vital importance, but it is the thinking standard of the anesthetist t h a t is of paramount importance. The normal human body can resist the sometime insults imposed on it by poor quality anesthesia, the end result being the same. However, one insult it cannot cope with is prolonged paraoperative reduction in deep-vein blood flow in the legs.
March, 1976, Vol. 91, No. 3
Annotations
In terms of hypovolemia, I believe t h a t m a n y anesthetists do not put up enough intravenous infusions (to cover paraoperative "normal" water requirements as well as blood), and d o not give enough fluid when the infusion is up. (How m a n y of your patients are thirsty after operation?) In some centers every patient has an intravenous drip put up before anesthesia begins. Somewhere between the two extremes probably is more satisfactory. We must all have seen patients for operation at midday who have had nothing to drink since late the previous evening, and who then on the operating table have to contend with further reduction in blood volume from bleeding and sweating. Surely a cup of tea and biscuit given not less t h a n four hours before premedication does no harm and can only help to stimulate blood flow? Looking further afield, could it be t h a t the published results following treatment for prevention of deep-vein thrombosis following cardiac infarction vary due to varying degrees of hydration? Are cases of venous thrombosis following strokes due to a fear of giving old people too much fluid? Do well controlled long-term unconscious patients in intensive-care units seem to show a relatively low incidence of leg deep-vein thrombosis because the central venous pressure is maintained more near normal? From other anesthetic aspects the prolonged recovery from anesthesia, with its accompanying immobilization and hypoventilation and recognized associated dangers, may produce a tranquil time for the patient, but is often due to an unnecessary "overdose" of anesthesia, or to incorrect timing in the giving of analgesics. In an operation where the patient is paralyzed and asleep, the anesthetist must largely concentrate on the likelihood of awareness and on the prevention of undue pain postoperatively. Of course, we want the patient preoperatively tranquil and postoperatively pain-free, but too much is too much. The likelihood of awareness, I believe, should be gauged on a mental estimation of the preoperative metabolic rate r a t h e r than body-weight per se. I have previously shown 3 t h a t the alteration in arterial Paco ~ following the same premedication (in Jamaica) shows an inverse linear relationship to metabolic rate as expressed as a percentage of normal. Thus a thinner, lighter, nervous individual may require more premedication and/or sleep agent than a fatter, heavier, b u t more tranquil one. This approach is supported by Claridge. 4 My experience further suggests t h a t patients in quiet, rural
"cottage" hospitals often need less narcotic agents t h a n those in busy city hospitals, as judged by sleep time following anesthesia. The routine giving of analgesics during anesthesia should also be carefully examined. When and why to give an agent is part of the unsung science of anesthesia. Is it for keeping the patient asleep by reducing sensory stimulus, to reduce adrenergic activity, or to anticipate an unknown postoperative pain status? Many schools of thought dislike adrenergic activity under anesthesia, but is it not better with a normal heart to permit some, thus allowing a better circulation to counteract a tendency to leg venous stasis and deep-vein thrombosis? Is it not also more "scientifiC" to assess pain as the patient awakes and to "titrate" the analgesic effect by small-dose intravenous analgesic injection? Thus, I believe, t h a t the modern anesthetist must think more broadly in terms of preserving a normal central venous pressure. Coupled with this he must ensure t h a t the preoperative patient is adequately sedated, but not oversedated {remember the accumulative night sedation effect); t h a t during the operation adrenergic activity in the normal patient should not be unduly suppressed; and t h a t postoperatively the patient should be quickly awake {after five minutes in recovery following a relaxant technique) with good muscle tone; and with postoperative pain tending to be treated by titration in the recovery room rather t h a n blindly on the oPerating table. These things, the avoidance of polypharmacy blindly given, and our physiotherapists, should be the greatest factors to concentrate on in the fight against deep-vein thrombosis.
J. Michael Simpson, M.B., B.S., F.F.A., R.C.S. St. Nicolaas Ziekenhuis Waalwijk, The Netherlands REFERENCES
1. Gallus, A. S., Hirsh, J., and Gent, M.: Relevance of preoperative and postoperative blood tests to postoperative leg-vein thrombosis, Lancet 2:805, 1973. 2. Simpson, J. M.: Fibrinolytic activity and postoperative deep-vein thrombosis, Lancet 1:352, 1974. {Letter to Eclitor). 3. Simpson, J. M.: Environmental temperature and reponse to premedicant drugs, Anaesthesia 25:508, 1970. 4. Claridge, G. S.: The relative influence of weight and of "nervous type" on the tolerance of a m y l o b a r b i t o n e sodium, Br. J. Anaes. 43:1121, 1971.
Of smoking and the respiratory tract
The publicity and propaganda t h a t smoking produces carcinoma of the lungs and heart disease have diverted the attention of all people from the more important fact that, even though these claims are true, the incidences of these illnesses are relatively minor when it is realized t h a t all (100 per cent) of the people who smoke have chronic diseases of their entire
American Heart Journal
respiratory tract. All smokers have chronic pharyngitis, chronic paranasal sinusitis, chronic laryngitis, chronic tracheitis, chronic bronchitis and bronchiectasis, and many are destined to have serious emphysema. Furthermore, acute respiratory tract infections are prone to develop upon these chronic diseases. Any physician who remembers or reviews the
401
