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Electrocardiographic changes in fulminating anoxia
300
i\MERICAN
HIL4R’l
JOURNAl.
rapid and shallow to cause anoxia, no depression of the RS-‘T segment was observed following hyperventilation. The alteration of the RS-T segments and the T-wave changes which may be observed in some women with endocrine imbalance is not due to hyperventilation. I)I:RAKT. Thill,
C. J., Treatment 1947.
and of
Meyer, 0. Subacute
0.: Experiences With Bacterial Endocarditis.
Penicillin Am. J.
and Dicumarol M. SC. 213:300
in the (March),
Of twenty-two patients with subacute bacterial endocarditis, thirteen received both penicillin and Dicumarol, and nine were given only penicillin. Despite the fact that the results were better in the group receiving combined therapy, the authors remain decidedly skeptical that anticoagulant therapy offers any advantages, and feel that it is unquestionabIe that anticoagulant therapy carries with it grave hazards in subacute bacterial endocarditis. Prolonged therapy, either with pencillin alone or combined with Dicumarol and persisting for a minimum of six weeks, gives decidedly better results than any other method. Sensitivity tests are of great value, since there is a good correlation between sensitivity and clinical response. It is of interest that five of the seven failures in this series occurred in patients who had received distinctly inadequate therapy before coming under observation, and this in spite of the fact that all but one of these had become subjectively and objectively improved under the original inadequate therapy. In one instance, it was found that penicillin given fourteen hours before and fifty-four hours after the extraction of a tooth, the dosage being 15,000 units every three hours, was inadequate to prevent the recurrence of subacute bacterial endocarditis in a patient whose disease had become arrested almost a year previously. DTRANT. Hodges, H. General
H., and Hospital.
Freeman, Am.
N. E.: Thrombophlebitis J. M. Sc. 213:226 (Feb.), 1947.
on
the
Medical
Service
of a
This report is based on ten instances of thrombophlebitis in the lower extremity observed in a General Hospital during a four-month period. Eight of these developed in patients with scrub typhus fever (an incidence of 5 per cent in 130 consecutive cases). Treatment, the authors believe, should be individualized depending on the location and extent of the lesion. When thrombophlebitis is confined to the calf veins, lumbar paravertebral sympathetic block was used with uniformly good results. This procedure probably tends to prevent central propagation of the thrombus, embolism did not occur, and patients were spared the prolonged disability which follows femoral vein ligation. Anticoagulants might help prevent propagation of the thrombosis, but their use is usually unnecessary, and is prohibited in the presence of lumbar sympathetic block because of the danger of retroperitoneal hembrrhage. Thrombophlebitis involving the calf and femoral veins was treated by proximal ligation. Sympathetic block was used only for relief of pain after ligation. In one case of calf vein thrombosis with extension into the femoral vein, paravertebral procaine block prior to femoral ligation was follow~ed promptly by pulmonary embolism. Iliofemoral thrombophlebitis was treated with heparin, high ligation being inadvisable in these ill patients. The results were satisfactory. In addition to the specific measures all patients were treated with elevation of the extremity, compression bandage, bed exercises, and early mobilization. From their observations the authors believe that all cases of iliofemoral thrombophlebitis do not necessarily result from extension of a calf vein thrombosis; such a process may originate occasionally in the iliofemoral region. I~R.~T\‘T. King,
B. G.. J. Aviation
and Henson, Med. 18:3
M.: (Feb.),
Electrocardiographic 1947.
Changes
in
Fulminating
Anoxia.
The authors investigated the rapidity with which electrocardiographic changes can occur in rapidly developing anoxia during altitude flights to obtain a better understanding of the mechanisms of rapidly deteriorating physiologic states, and to obtain information on the mechanisms underlying functional electrocardiographic changes. Special attention was given to the voltage and configuration of the P, QRS, and T deflections, S-T segment deviations, and durations of the P-R and Q-T intervals.
SELECTED
ABSTRACTS
301
Anesthetized dogs were suddenly transferred from 100 per cent oxygen to 100 per cent helium or nitrogen. This procedure resulted in a most severe degree of anoxic anoxia which led to reCardiac failure occurred shortly thereafter, and respiratory failure within 120 to 240 seconds. suscitative measures, applied four to five minutes after starting inhalation of the inert gas, failed in four of the nine cases in which remedial measures were attempted. Records were taken from the first three standard leads during each minute of inhalation. The heart showed such marked changes in conduction, rhythm, or in origin of the beat, either before or shortly after the third minute of anoxia, that comparison of voltages, configurations, and intervals with control values was no longer warranted. The most dramatic change during the period of co-ordinate activity was the increase in the potential of the T wave. The R wave decreased in voltage in two leads in seven of the eight dogs during exposure to helium and in seven of the eight during exposure to nitrogen. No significant or consistant change in the voltage of the P wave was observed. A high take off of the T wave was observed in five dogs breathing helium and in four dogs breathing nitrogen. Slowing of the heart after the initial acceleration occurred during the first minute in a majority of the dogs, although the acceleration stage was observed as late as the third minute in a few instances. The P-R intervals were all within the normal range as long as there was co-ordinate activity of the heart. Changes in QRS interval were within normal limits; such small changes as did occur being about equally divided between increased and decreased duration. Human subjects breathing air were exposed for brief periods to simulated altitudes of 25,000 and 35,000 feet. In some instances, successive recordings of the first three standard leads were made during the development of anoxia. In others, progressive changes were followed in Lead II. There was a consistant decrease in the voltage of the T wave in all of the eleven observations on seven subjects. Of the five subjects exposed to both altitudes, three showed the greater change at 35,000 feet and two at 25,000 feet. At the higher altitude changes were noted in ten seconds Exposure in four subjects, in thirty seconds in one subject, and in ninety seconds in one subject. to 25,000 feet resulted in changes in thirty to sixty seconds. At this altitude, transient increases in potential were noted in two cases after two and four minutes. Changes in the R-wave potential were not consistent, but decrease in voltage occurred in four cases, with no change in five cases, and an initial increase of voltage with a return to the control value in two subjects. Small increases in the voltage of the P wave were seen in eight of the eleven trials. No significant changes in the P-R or the QRS intervals, or the S-T segment were noted. The authors believe that the electrocardiographic changes which occur during brief exposure to anoxic anoxia are almost certainly attributable to functional changes and/or to shifts in the electrical axis of the heart rather tha.n to permanent damage of the cardiac muscle. BELLET. Dry,
T. J., Butt, H. R., and Scheifley, C. H.: The Effect of Oral Administration Aminobenzoic Acid on the Concentration of Salicylates in the Blood: Report. Proc. Staff. Meet., Mayo Clin. 21:497 (Dec. 24), 1946.
of ParaPreliminary
The authors suggest that the action of salicylates in rheumatic fever may be more specific than has been recently supposed. It is known that rheumatic fever affects predominantly mesenchymal structures, the principal substrate of which is hyaluronic acid. The younger the tissue, the more readily will diffusion take place; and any agent capable of hydrolyzing hyaluronic acid increases this property. The enzyme, hyaluronidase (derived from many strains of hemolytic types of streptococci and from extracts of umbilical cord and testes), is capable of just this action: it decreases the viscosity and .favors the passage of liquids, exudates, and pathogenic tissues. When dyes are injected into the skin, the addition of hyaluronidase causes an increased diffusibility of these dyes, as demonstrated in both human beings and animals by Guerra. What is more impressive is that the extent of the spread is inhibited 57 to 66 per cent by the oral or intravenous administration of sodium salicylate, and that the degree of inhibition varies according to the dose of salicylate administered. These observations are illuminating from the standpoint of the etiology and behavior of rheumatic fever when they are considered in the light of an enzyme system capable of producing
i\MERICAN
HIL4R’l
JOURNAl.
rapid and shallow to cause anoxia, no depression of the RS-‘T segment was observed following hyperventilation. The alteration of the RS-T segments and the T-wave changes which may be observed in some women with endocrine imbalance is not due to hyperventilation. I)I:RAKT. Thill,
C. J., Treatment 1947.
and of
Meyer, 0. Subacute
0.: Experiences With Bacterial Endocarditis.
Penicillin Am. J.
and Dicumarol M. SC. 213:300
in the (March),
Of twenty-two patients with subacute bacterial endocarditis, thirteen received both penicillin and Dicumarol, and nine were given only penicillin. Despite the fact that the results were better in the group receiving combined therapy, the authors remain decidedly skeptical that anticoagulant therapy offers any advantages, and feel that it is unquestionabIe that anticoagulant therapy carries with it grave hazards in subacute bacterial endocarditis. Prolonged therapy, either with pencillin alone or combined with Dicumarol and persisting for a minimum of six weeks, gives decidedly better results than any other method. Sensitivity tests are of great value, since there is a good correlation between sensitivity and clinical response. It is of interest that five of the seven failures in this series occurred in patients who had received distinctly inadequate therapy before coming under observation, and this in spite of the fact that all but one of these had become subjectively and objectively improved under the original inadequate therapy. In one instance, it was found that penicillin given fourteen hours before and fifty-four hours after the extraction of a tooth, the dosage being 15,000 units every three hours, was inadequate to prevent the recurrence of subacute bacterial endocarditis in a patient whose disease had become arrested almost a year previously. DTRANT. Hodges, H. General
H., and Hospital.
Freeman, Am.
N. E.: Thrombophlebitis J. M. Sc. 213:226 (Feb.), 1947.
on
the
Medical
Service
of a
This report is based on ten instances of thrombophlebitis in the lower extremity observed in a General Hospital during a four-month period. Eight of these developed in patients with scrub typhus fever (an incidence of 5 per cent in 130 consecutive cases). Treatment, the authors believe, should be individualized depending on the location and extent of the lesion. When thrombophlebitis is confined to the calf veins, lumbar paravertebral sympathetic block was used with uniformly good results. This procedure probably tends to prevent central propagation of the thrombus, embolism did not occur, and patients were spared the prolonged disability which follows femoral vein ligation. Anticoagulants might help prevent propagation of the thrombosis, but their use is usually unnecessary, and is prohibited in the presence of lumbar sympathetic block because of the danger of retroperitoneal hembrrhage. Thrombophlebitis involving the calf and femoral veins was treated by proximal ligation. Sympathetic block was used only for relief of pain after ligation. In one case of calf vein thrombosis with extension into the femoral vein, paravertebral procaine block prior to femoral ligation was follow~ed promptly by pulmonary embolism. Iliofemoral thrombophlebitis was treated with heparin, high ligation being inadvisable in these ill patients. The results were satisfactory. In addition to the specific measures all patients were treated with elevation of the extremity, compression bandage, bed exercises, and early mobilization. From their observations the authors believe that all cases of iliofemoral thrombophlebitis do not necessarily result from extension of a calf vein thrombosis; such a process may originate occasionally in the iliofemoral region. I~R.~T\‘T. King,
B. G.. J. Aviation
and Henson, Med. 18:3
M.: (Feb.),
Electrocardiographic 1947.
Changes
in
Fulminating
Anoxia.
The authors investigated the rapidity with which electrocardiographic changes can occur in rapidly developing anoxia during altitude flights to obtain a better understanding of the mechanisms of rapidly deteriorating physiologic states, and to obtain information on the mechanisms underlying functional electrocardiographic changes. Special attention was given to the voltage and configuration of the P, QRS, and T deflections, S-T segment deviations, and durations of the P-R and Q-T intervals.
SELECTED
ABSTRACTS
301
Anesthetized dogs were suddenly transferred from 100 per cent oxygen to 100 per cent helium or nitrogen. This procedure resulted in a most severe degree of anoxic anoxia which led to reCardiac failure occurred shortly thereafter, and respiratory failure within 120 to 240 seconds. suscitative measures, applied four to five minutes after starting inhalation of the inert gas, failed in four of the nine cases in which remedial measures were attempted. Records were taken from the first three standard leads during each minute of inhalation. The heart showed such marked changes in conduction, rhythm, or in origin of the beat, either before or shortly after the third minute of anoxia, that comparison of voltages, configurations, and intervals with control values was no longer warranted. The most dramatic change during the period of co-ordinate activity was the increase in the potential of the T wave. The R wave decreased in voltage in two leads in seven of the eight dogs during exposure to helium and in seven of the eight during exposure to nitrogen. No significant or consistant change in the voltage of the P wave was observed. A high take off of the T wave was observed in five dogs breathing helium and in four dogs breathing nitrogen. Slowing of the heart after the initial acceleration occurred during the first minute in a majority of the dogs, although the acceleration stage was observed as late as the third minute in a few instances. The P-R intervals were all within the normal range as long as there was co-ordinate activity of the heart. Changes in QRS interval were within normal limits; such small changes as did occur being about equally divided between increased and decreased duration. Human subjects breathing air were exposed for brief periods to simulated altitudes of 25,000 and 35,000 feet. In some instances, successive recordings of the first three standard leads were made during the development of anoxia. In others, progressive changes were followed in Lead II. There was a consistant decrease in the voltage of the T wave in all of the eleven observations on seven subjects. Of the five subjects exposed to both altitudes, three showed the greater change at 35,000 feet and two at 25,000 feet. At the higher altitude changes were noted in ten seconds Exposure in four subjects, in thirty seconds in one subject, and in ninety seconds in one subject. to 25,000 feet resulted in changes in thirty to sixty seconds. At this altitude, transient increases in potential were noted in two cases after two and four minutes. Changes in the R-wave potential were not consistent, but decrease in voltage occurred in four cases, with no change in five cases, and an initial increase of voltage with a return to the control value in two subjects. Small increases in the voltage of the P wave were seen in eight of the eleven trials. No significant changes in the P-R or the QRS intervals, or the S-T segment were noted. The authors believe that the electrocardiographic changes which occur during brief exposure to anoxic anoxia are almost certainly attributable to functional changes and/or to shifts in the electrical axis of the heart rather tha.n to permanent damage of the cardiac muscle. BELLET. Dry,
T. J., Butt, H. R., and Scheifley, C. H.: The Effect of Oral Administration Aminobenzoic Acid on the Concentration of Salicylates in the Blood: Report. Proc. Staff. Meet., Mayo Clin. 21:497 (Dec. 24), 1946.
of ParaPreliminary
The authors suggest that the action of salicylates in rheumatic fever may be more specific than has been recently supposed. It is known that rheumatic fever affects predominantly mesenchymal structures, the principal substrate of which is hyaluronic acid. The younger the tissue, the more readily will diffusion take place; and any agent capable of hydrolyzing hyaluronic acid increases this property. The enzyme, hyaluronidase (derived from many strains of hemolytic types of streptococci and from extracts of umbilical cord and testes), is capable of just this action: it decreases the viscosity and .favors the passage of liquids, exudates, and pathogenic tissues. When dyes are injected into the skin, the addition of hyaluronidase causes an increased diffusibility of these dyes, as demonstrated in both human beings and animals by Guerra. What is more impressive is that the extent of the spread is inhibited 57 to 66 per cent by the oral or intravenous administration of sodium salicylate, and that the degree of inhibition varies according to the dose of salicylate administered. These observations are illuminating from the standpoint of the etiology and behavior of rheumatic fever when they are considered in the light of an enzyme system capable of producing