Advertisement

Canadian Anaesthetists’ Society Journal

, Volume 4, Issue 3, pp 295–337 | Cite as

The physiological effects of intravenous anaesthesia on man

  • Allen B. Dobkin
  • Gordon M. Wyant
Article

Summary and Conclusions

The problems of comparing several anaesthetics are reviewed with particular reference to the effects of premedication, the intrinsic activity of drugs and their affinity for certain tissues and the effect of multiple drug interaction. The physiological and pathological states of those patients who are used as subjects of such studies are essential factors to be clearly determined. The effects of acute tolerance, cumulation and tachyphylaxis were also cited as factors to be considered.

A controlled study of respiratory and haemodynamic parameters was carried out on eight young healthy male subjects in order to determine the principal and statistically significant effects of thiopental, thiamylal, hexobarbital, buthalitone, methitural, Compound 25398 and Dolitrone.

Resting vital signs were initially obtained as well as other vital statistics. Basal metabolism and cardio-respiratory parameters were determined from nomograms related to the resting values These data provided the base line for all control and experimental data Plasma volume and red cell volume were initially determined simultaneously with radioactive iodinated human serum albumin (I131) and radioactive chromium51, employing the dilution principle. These were checked against venous haematocrit determinations.

Respiration data were obtained on a recording spirometer which also recorded oxygen consumption Cardiovascular data (arterial and venous blood pressure) were recorded via intra-arterial and intravenous needles attached to Statham strain gauges, oscilloscopes and a photographic recorder. The pulse rate and electrocardiogram (lead 2) were also recorded on this system The cardiac output was estimated by external body-counting of I131 following single injections of Rihsa, using a shielded scintillation detector directed over a fixed site on the chest where tissue circulation was minimal, in order to measure primarily the blood flow in the aortic arch. Mean circulation time and cardiac output were derived from measurements on the recordings, and stroke volume, total peripheral resistance, left ventricular work and intrathoracic blood volume were computed from the above data.

All data were analysed for mean alterations, and statistical significance was computed to determine the probability (P value) of random variation by the method of the Fishert-test.

The accuracy of the technical procedures employed was reviewed, with particular reference to the newer methods for estimating blood volume, cardiac output and mean circulation time, and was found to compare reliably with that of tried and recognized methods The limitations of clinical studies were also discussed, and data from animal studies were reviewed with a view to supplementing information on the toxicity and cumulative effects of these drugs.

A conservative evaluation of the results was essential in this study since it was assumed that deviations of values were normally distributed, and that the study dealt essentially with the healthiest type of subjects one ever encounters in clinical practice The authors also felt, as noted by Johnson and Van Harreveld, that so many factors are involved in cardiorespiratory regulation, both before and during anaesthesia, that one must be extremely cautious in stating which factor is primarily involved in a change. One must therefore avoid conclusions from individual changes and base critical evaluation on consistent and statistically significant changes in a “homogenous” group, and then perhaps apply these data to an individual.

From the experiments the seven intravenous anaesthetics studied could be divided into two mam groups: those that produced a prolonged depression of respiration and circulation; and those that produced a brief depression of these parameters. Compound 25398, thiamylal and thiopental belong to the first group, while methitural, Dolitrone, hexobarbital and buthalitone belong to the second. All the drugs except hexobarbital depressed oxygen consumption. Tachycardia was a significant finding with all the drugs except methitural and acute hypotension (arterial and venous) was a consistent finding with all the drugs. Considering all the parameters, myocardial depression was induced by the first group, but this was not consistently manifested by a decrease in the cardiac output.

From this investigation, it is difficult to choose among the agents and state which disturbs human physiology to the least extent while providing clinically adequate hypnosis. It is only possible to state the advantage of a particular agent with reference to a specific patient, a specific type of operation and a specific clinical situation On this basis, extensive clinical experience with one agent is probably the most reliable method of managing most situations, for then the problem comes down to a matter of dosage, concentration of the drug, and rate of its administration.

Keywords

Cardiac Output Venous Pressure Thiopental CANADIAN Anaesthetist Total Peripheral Resistance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Résumé

Nous avons étudié les problèmes que pose la comparaison de plusieurs anesthésiques en prêtant une attention particuliére aux effets de la prémédication, à ľactivité intrinsèques des médicaments et à leur affinité pour certains tissus, puis, enfin, à ľeffet de ľinteraction de plusieurs médicaments Il nous faut donner des précisions sui la condition physio-pathologique des malades chez qui on a employé ces médicaments pour les étudier. Nous avons également mentionné comme facteurs non négligeables, la tolérance aigue, ľaccumulation et la tachyphylaxie.

Nous avons fait, chez huit jeunes sujets mâles en santé, une étude, avec contrôles, des paramètres respiratoires et hémodynamiques pour tabuler les effets principaux et les effets présentant un intérêt statistique sur le thiopental, le thiamylal, ľhexobarbital, le buthalitone, le methitural, le composé 25398 et le dolitrone.

Nous avons ďabord cherché les signes vitaux à ľétat de repos de même que ďautres statistiques vitales Le métabolisme de base et les paramètres cardiorespiratoires ont été tirés des nomogrammes donnant les valeurs à ľétat de repos Ces résultats nous ont fourni les bases pour les données de contrôle et expérimentales Les volumes plasmatique et globulaire ont été recherchés simultanément au début avec le sérum albumine humain iodé radioactif (I131) et le chromium radioactif51 en employant le principe de dilution. Ces deux résultats ont été comparés aux déterminations de ľhématocrite sur le sang vemeux.

Au sujet de la respiration, les données ont été obtenues au moyen ďun spiromètre enregistreur renseignant également sur la consommation ďoxygène. Les renseignements sur le système cardiovasculaire (pression artérielle et veineuse) ont été obtenus et enregistrés au moyen ďaiguilles placées dans les artères et dans les veines et reliées au manomètres Statham, aux oscilloscopes et à un enregistreur photographique.

Le rythme cardiaque et ľélectrocardiogramme (en deuxième dérivation) ont également été enregistrés sur le même système Le débit cardiaque a été évalué de ľextérieur de ľorganisme en repérant ľI131, après une seule injection de Rihsa, et en promenant un détecteur à champ scintillant au-dessus ďun endroit précis sur le thorax où la circulation tissulaire est réduite de façon à obtenir principalement le débit sanguin de la crosse aortique. La moyenne du temps de circulation et le débit cardiaque ont été obtenus de ces enregistrements, et le débit systolique, la résistance périphérique totale, le travail du ventricule gauche et le volume de sang intrathoracique ont été calculés ďaprès ces données

Tous les résultats ont été analysés pour trouver la moyenne des modifications et la signification statistique a été calculée pour obtenir la probabilité (la valeurP) de variation isolée par la méthode de Fisher.

Nous avons contrôlé la précision des techniques employées, plus particulièrement les techniques nouvelles pour mesurer le volume sanguin, le débit cardiaque et la moyenne du temps de circulation et nous pouvons affirmer que les résultats sont comparables à ceux obtenus par ďautres techniques éprouvées et reconnues Nous avons également discuté des limites des études cliniques et les résultats des études faites sur ľanimal ont été étudiés dans le but ďobtenir des renseignements additionnels sur la toxicité et les effets cumulatifs de ces médicaments.

Dans cette étude, il était essentiel ďavoir une évaluation conservatrice des résultats car nous présumions que la déviation des résultats était répartie normalement et que ľétude a été faite sur des sujets les plus en santé qu’on puisse trouver en clinique. Les auteurs ont également eu la conviction, comme ľaffirment Johnson et Van Harreveld, qu’il y a tellement de facteurs impliqués dans le maintien de ľéquilibre cardiorespiratoire, aussi bien avant que pendant ľanesthésie, qu’il faut être très prudent avant ďaffirmer que tel ou tel facteur est primitivement responsable ďun changement Conséquemment, il faut éviter de conclure ďaprès des changements individuels et baser une évaluation critique sur des changements considérables et ďimportance statistique observés sur un groupe homogène et après, peut-être, comparer ces données à ľindividu.

D’après ces expériences, on peut diviser en deux groupes les sept agents anesthésiques étudiés, il s’agit ďagents administrés par voie endoveineuse: ceux qui ont entraîné une dépression prolongée de la respiration et de la circulation et ceux qui ont entraîné une brève dépression sur ces paramètres. Le composé 25398, le thiamylal et thiopental appartiennent au premier groupe, tandis que le methitural, le dolitrone, ľhexobarbital et le buthalitone appartiennent au dernier groupe. Tous ces médicaments diminuent la consommation ďoxygène à ľexception de ľhexobarbital. On a observé une tachycardie importante à la suite de ľadministration de tous ces médicaments à ľexception du méthitural et une hypotension marquée (artérielle et veineuse) à la suite de ľadministration de chacun de ces médicaments En analysant tous les résultats, on note que les médicaments du premier groupe ont causé une dépression myocardique mais elle n’a pas toujours été accompagnée ďune diminution du débit cardiaque.

Après cette enquête, il demeure difficile ďaffirmer lequel de ces agents cause le moins de changement dans la physiologie humanie tout en procurant une hypnose adéquate cliniquement. Il nous est possible tout au plus de mentionner la supériorité ďun agent en particulier pour tel ou tel malade, ou encore pour telle sorte ďopération ou pour une situation clinique particulière. En se basant sur ces faits, nous pouvons affirmer qu’une longue expérience clinique avec un agent demeure probablement le facteur le plus sûr pour contrôler toutes les éventualités, car le problème se résume à une question de dosage, de dilution de médicament et de vitesse ďadministration.

References

  1. 1.
    Keating, V. Anaesthesia Accidents, pp 136.et seq London: Lloyd-Luke (1956).Google Scholar
  2. 2.
    Stephenson, H. E., Reid, L. C. &Hinton, J. W. Some Common Denominators in 1200 Cases of Cardiac Arrest. Ann. Surg.,137: 731 (1953).PubMedCrossRefGoogle Scholar
  3. 3.
    Beecher, H. K. &Todd, D. P. A Study of the Deaths Associated with Anaesthesia and Surgery. Ann. Surg.,140: 2 (1954).PubMedCrossRefGoogle Scholar
  4. 4.
    Edwards, G., Morton, H. J. V., Pask, E. A. &Wylie, W. D. Deaths Associated with Anaesthesia. Anaesthesia,11: 194 (1956).PubMedCrossRefGoogle Scholar
  5. 5.
    Editorial. Influence of Opiales upon Experimental Results. Anesthesiology,17: 616 (1956)Google Scholar
  6. 6.
    Wangeman, C. P. &Hawk, M. H. The Effects of Morphine, Atropine and Scopolamine on Human Subjects. Anesthesiology,3: 24 (1942).CrossRefGoogle Scholar
  7. 7.
    Cohen, E. N. &Beegher, H. K. Narcotics in Preanaepthetic Medication—Controlled Study. Report to Council on Pharmacy and Chemistry. J.A.M.A.,147: 1664 (1951).Google Scholar
  8. 8.
    Dobkin, A. B., Gilbert, R. G. B. &Melville, K. I. Chlorpromazine Review and Investigation as a Premedicant m Anesthesia. Anesthesiology,17: 135 (1956).PubMedCrossRefGoogle Scholar
  9. 9.
    Helrich, M., Eckenhoff, J. E., Jones, R. E. &Rolph, W. D. Influence of Opiates on the Respiratory Response of Man to Thiopental. Anesthesiology,17: 459 (1956)PubMedGoogle Scholar
  10. 10.
    Dobkin, A. B., Wyant, G. M. &Dyck, F. Clinical Evaluation of Methyprylon ( Noludar ) as a Preanaesthetic Sedative Hypnotic. Canad. Anaesth. Soc. J.,4: 27 (1957).PubMedCrossRefGoogle Scholar
  11. 11.
    Swerdlow, M. &Newman, J. Some Effects of Premedication. Brit. J. Anaesth.,29: 66 (1957).PubMedCrossRefGoogle Scholar
  12. 12.
    Dundee, J. W., Price, H. L. &Dripps, R. D. Acute Tolerance to Thiopentone in Man. Brit. J. Anaesth.,8: 344 (1956).CrossRefGoogle Scholar
  13. 13.
    Wyant, G. M., Kilduff, C. J., Merriman, J. E. &Dobkin, A. B. Evaluation of Dolitrone. Canad. Anaesth. Soc. J.,3: 291 (1956).Google Scholar
  14. 14.
    Wyant, G. M., Dobkin, A. B. &Kilduff, C. J. The Effect of Buthalitone Sodium ( Transithal® ) on Liver and Kidney Function in Man. Canad. Anaesth. Soc. J.,4: 21 (1957).PubMedCrossRefGoogle Scholar
  15. 15.
    Radford, E. P. Ventilation Standards for Use in Artificial Respiration. J. Appl. Physiol.,7: 451 (1955).PubMedGoogle Scholar
  16. 16.
    Jackson, C. E. Nomogram for Simple Calculation of Cardiac Output. Circulation,11: 635 (1955).PubMedGoogle Scholar
  17. 17.
    Stead, E. A., Warren, J. V., Merrill, A. J. &Brannon, E. S. The Cardiac Output in Male Subjects as Measured by the Technique of Right Atrial Catheterization Normal Values with Observations on the Effect of Anxiety and Tilting. J. Clin. Investigation,24: 326 (1945).CrossRefGoogle Scholar
  18. 18.
    Hickam, J. B., Cargill, W. H. &Golden, A. Cardiovascular Reactions to Emotional Stimuli. Effect on Cardiac Output, Arteriovenous Oxygen Difference, Arterial Pressure and Peripheral Resistance. J. Clin. Investigation,27: 290 (1948).CrossRefGoogle Scholar
  19. 19.
    Henschel, A. B., Wyant, G. M., Dobkin, A. B. &Henschel, E. O. Posture as It Concerns the Anesthesiologist. A Preliminary Study. Anesth. and Analg.,36: 69 (1957).Google Scholar
  20. 20.
    O’Mullane, E. J. The Investigation of a Short-Acting Barbiturate, Illustrating the Fallacies of Clinical Impressions. Brit. J. Anaesth.,29: 71 (1957).PubMedCrossRefGoogle Scholar
  21. 21.
    Gray, S. J. &Sterling, K. Determination of Circulating Red Cell Volume in Man by Radioactive Chromium. J. Clin. Investigation,29: 1604 (1950).CrossRefGoogle Scholar
  22. 22.
    Sterling, K. &Gray, S. J. Determination of Circulating Red Cell Volume in Man with Radioactive Chromium. J. Clin. Investigation,29: 1614 (1950).CrossRefGoogle Scholar
  23. 23.
    Crispell, K. R., Porter, B. &Nieset, R. T. Studies of Plasma Volume Using Human Serum Albumin Tagged with Radioactive Iodine (I131). J. Clin. Investigation,29: 513 (1950).CrossRefGoogle Scholar
  24. 24.
    Storaasli, J. P., Krieger, H., Friedell, H. L. &Holden, W. D. Use of Radioactive Iodmated Plasma Protein in Study of Blood Volume. Surg., Gynec. & Obst.,91: 458 (1950).Google Scholar
  25. 25.
    Erickson, J. R., McCormick, J. B. &Seed, L. Improved Method for Determination of Blood Volume Using Radioactive Iodmated Human Serum Albumin. Science,118: 595 (1953).PubMedCrossRefGoogle Scholar
  26. 26.
    Gray, S. J. &Frank, H. The Simultaneous Determination of Red Cell Mass and Plasma Volume in Man with Radioactive Sodium Chromate and Chromic Chloride. J. Clin. Investigation,32: 1000 (1953).CrossRefGoogle Scholar
  27. 27.
    Dobkin, A. B. Effect of Chlorpromazine on Blood Volume, Venous Pressure and Circulation Time Estimations. Anaesthesia, in press (1957).Google Scholar
  28. 28.
    Lyons, R. H., Kennedy, J. A. &Burwell, C. S. The Measurement of Venous Pressure by the Direct Method. Am. Heart J.,16: 675 (1938).CrossRefGoogle Scholar
  29. 29.
    Fry, D. L., Noble, F. W. &Mallos, A. S. An Evaluation of Modern Pressure Recording Systems. Clin. Res.,5: 40 (1957).Google Scholar
  30. 30.
    Veall, N., Pearson, J. D., Hanley, T. &Lowe, A. E. A Method for the Determination of Cardiac Output (Preliminary Report), pp 183–192. Proc. 2nd Radioisotope Conference, Oxford, July 19–23 (1954), London: Butterworth’s Scientific Publications (1954).Google Scholar
  31. 31.
    Huff, R. L., Feller, D. D., Judd, O. J. &Bogardus, G. M. Cardiac Output of Men and Dogs Measured byin vivo Analysis of Iodmated (I131) Human Serum Albumin. Circ. Res.,3: 564 (1955).PubMedGoogle Scholar
  32. 32.
    Shipley, R. A., Clark, R. E., Liebowitz, D. &Krohmer, J. S. Analysis of the Radiocardiogram in Heart Failure. Cure. Res.,1: 428 (1953).Google Scholar
  33. 33.
    Shipley, R. A. &Clark, R. E. Measurement of Circulation Times with NaI131. Circ. Res.,4: 456 (1956).PubMedGoogle Scholar
  34. 34.
    Cyvin, K. Calculation of Cardiac Output by Estimation with Dilution Method. Acta Physiol. Scandmav,19: 57 (1949).CrossRefGoogle Scholar
  35. 35.
    Hamilton, W. F., Moore, J. W., Kinsman, J. M. &Sparling, R. G. Studies on the Circulation IV Further Analysis of the Injection Method and of Changes in Hemodynamics under Physiological and Pathological Conditions. Am. J. Physiol.,99: 534 (1932).Google Scholar
  36. 36.
    Shipley, R. A. Personal communication.Google Scholar
  37. 37.
    Apiera, A. Total Peripheral Resistance Formula Skandmav. Arch. f. Physiol., Suppl.16: 1 (1940), quoted by R Shackmanet al.Google Scholar
  38. 38.
    Johnson, S. R. The Effect of Some Anaesthestic Agents on the Circulation in Man. Acta chir. Scandmav, Suppl. 158 (1951).Google Scholar
  39. 39.
    Remington, J. W. &Hamilton, W. F. The Evaluation of the Work of the Heart. Am. J. Physiol.,150: 267 (1947).Google Scholar
  40. 40.
    Stewart, G. N. The Pulmonary Circulation Time, the Quantity of Blood m the Lungs and the Output of the Heart. Am. J. Physiol.,58: 20 (1921).Google Scholar
  41. 41.
    Newman, E. V.et al. The Dye Dilution Method for Describing the Central Circulation: An Analysis of Factors Shaping the Time Concentration Curves. Circulation,4: 735 (1951).PubMedGoogle Scholar
  42. 42.
    Kattus, A. A., Rivin, A. U., Cohen, A. &Sofia, G. S. Cardiac Output and Central Volume as Determined by Dye Dilution Curves Resting Values in Normal Subjects and Patients with Cardiovascular Disease. Circulation,11: 447 (1955).PubMedGoogle Scholar
  43. 43.
    Hamilton, W. F. The Physiology of the Cardiac Output. Circulation,8: 527 (1953).PubMedGoogle Scholar
  44. 44.
    Ebert, R. V., Borden, C. W., Wells, H. S. &Wilson, R. H. Studies of the Pulmonary Circulation I The Circulation Time from Pulmonary Artery to the Femoral Artery and the Quantity of Blood in the Lungs m Normal Individuals. J. Clin. Investigation,28: 1134 (1949).CrossRefGoogle Scholar
  45. 45.
    MacIntyre, W. J. &Leonards, J. R. A Method for Continuously Recording the Disappearance of Radioactive Tracers from Circulating Blood. Circ. Res.,3: 14 (1955).PubMedGoogle Scholar
  46. 46.
    Pritchard, W. H., Mom, T. W. &MacIntyre, W. J. Measurement of the Early Disappearance of Iodmated (I131) Serum Albumin from Circulating Blood by a Continuous Recording Method. Circ. Res.,3: 19 (1955).PubMedGoogle Scholar
  47. 47.
    MacIntyre, W. J., Pritchard, W. H., Mom, T. W. &Friedell, H. Some Studies on the Determination of Cardiac Output by the Dilution Method without Arterial Sampling Abstract Internat. J. Appl. Radiation & Isotopes,1: 136 (1956).Google Scholar
  48. 48.
    Hicks, D. A., Hope, A., Turnbull, A. L. &Verel, D. The Prediction and Estimation of Normal Blood Volume. Clin. Sc.,15: 557 (1956).Google Scholar
  49. 49.
    Hamilton, W. F.et al. Comparison of the Fick and the Dye Injection Method of Measuring the Cardiac Output in Man. Am. J. Physiol.,153: 309 (1948).PubMedGoogle Scholar
  50. 50.
    Conn, H. L. Accuracy of a Radiopotassium Dilution (Stewart Principle) Method for Measurement of Cardiac Output. J. Appl. Physiol.,7: 542 (1955).PubMedGoogle Scholar
  51. 51.
    Karpeles, L. M. &Huff, R. L. Blood Volume of Representative Portions of the Musculo-Skeletal System in Man. Circ. Res.,3: 483 (1955).PubMedGoogle Scholar
  52. 52.
    MacIntyre, W. J., Pritchard, W. H., Eckstein, R. W. &Friedell, H. L. The Determination of Cardiac Output by a Continuous Recording System Utilizing Iodmated (I131) Human Serum Albumin I Animal Studies. Circulation,4: 552 (1951).PubMedGoogle Scholar
  53. 53.
    Pritchard, W. H., MacIntyre, W. J., Schmidt, W. C., Bronfman, B. L. &Moore, D. J. The Determination of Cardiac Output by a Continuous Recording System Utilizing Iodmated (I131) Human Serum Albumin II Clinical Studies. Circulation,6: 572 (1952).PubMedGoogle Scholar
  54. 54.
    Lammerant, J., Spbumont, P. &De Visscher, M. Registration of Intracardiac Blood Flow for Man A Radioisotope Dilution Technique. Arch. internat de physiol. et de biochem.,74: 1 (1956).Google Scholar
  55. 55.
    Prinzmetal, M., Corday, E., Spritzler, R. J. &Flieg, W. Radiocardiography and Its Clinical Application. J.A.M.A.,139: 617 (1949).Google Scholar
  56. 56.
    Huff, R. L.,Parrish, D. &Crockett, W. Simultaneous Recordings of Radiation (I131) Transients from Four Crystal Detectors on the Anterior Thoracic Wall. Bulletin of U.S. A. E. C., No. AT (45-1)-978.Google Scholar
  57. 57.
    Van Harreveld, A. &Shadle, O. W. On Hemodynamics. Arch. internat de physiol.,59: 165 (1951).CrossRefGoogle Scholar
  58. 58.
    Elder, J. D., Nagano, S. M., Eastwood, D. W. &Harnagel, D. Circulatory Changes Associated with Thiopental Anaesthesia in Man. Anesthesiology,16: 394 (1955).PubMedCrossRefGoogle Scholar
  59. 59.
    Moon, V. H. Shock Its Dynamics, Occurrence and Management, pp 24,et seq Philadelphia: Lea and Febiger (1942).Google Scholar
  60. 60.
    Pierce, V. K., Boyan, C. P. &Masterson, J. G. Studies on Venous Blood Pressure in Patients Undergoing Major Surgical Procedures. Surg. Gynec. & Obst.,96: 310 (1953).Google Scholar
  61. 61.
    Daniel, E. E., Fulton, J. B., Hiddleston, M., Martin, W. &Foulks, J. G. An Analysis of the Mechanism of Barbiturate Induced Cardiovasculai Depression and Its Antagonism by Sympathomimetic Amines. Arch. internat de pharmacodyn et de therap.,108: 457 (1956).Google Scholar
  62. 62.
    Brodie, B. B., Burns, J. J., Mark, L. C., Lief, P. A., Bernstein, E. &Papper, E. M. The Fate of Pentobarbital in Man and Dog and a Method for Its Estimation in Biological Material. J. Pharmacol. & Exper. Therap.,109: 26 (1953).Google Scholar
  63. 63.
    Wyngaarden, J. B., Woods, L. A., Ridley, R. &Seevers, M. H., Anesthetic Properties of Sodium 5-Allyl 5-(l-Methyl-butyl)-2 Thiobarbiturate (Surital) and Certain Other Thiobarbiturates in Dogs. J. Pharmacol. & Exper. Therap.,95: 322 (1949).Google Scholar
  64. 64.
    Woods, L. A., Wyngaarden, J. B., Rennick, B. &Seevers, M. H. Cardiovascular Toxicity of Thiobarbiturates Comparison of Thiopental and Surital in Dogs. J. Pharmacol. & Exper. Therap.,95; 328 (1949).Google Scholar
  65. 65.
    Prime, F. J. &Gray, T. C. The Effect of Certain Anaesthetic and Relaxant Agents on Circulatory Dynamics. Brit. J. Anaesth.,24: 101 (1952).PubMedCrossRefGoogle Scholar
  66. 66.
    Boniface, K. G. &Brown, J. M. Quantitative Evaluation of Cardiovascular Stimulant Drugs in Barbiturate Depression of the Heart of the Dog. Anesthesiology,14: 23 (1953).PubMedCrossRefGoogle Scholar
  67. 67.
    Imig, C. J., Randall, B. F. &Hines, H. M. Effect of Pentobarbital Sodium Anesthesia upon Volume Blood Flow, Arterial Pressure and Heart Rate. Proc. Soc. Exper. Biol. & Med.,82: 9 (1953).Google Scholar
  68. 68.
    Greisheimer, E. M., Ellis, D. W., Baier, H. N., Ring, G. C., Makarenko, L. &Graziano, J. Cardiac Output by Cuvette Oximeter under Thiopental. Am. J. Physiol.,175: 171 (1953).PubMedGoogle Scholar
  69. 69.
    Weese, M. &Koss, F. H. Ueber em neues Ultrakurznarkoticum. Deutsche med. Wochnschr.,79: 601 (1954).CrossRefGoogle Scholar
  70. 70.
    Irwin, S., Stagg, R. D., Dunbar, E. &Govier, W. M. Methitural, a New Intravenous Anaesthetic Comparison with Thiopental in the Cat, Dog and Monkey. J. Pharmacol. & Exper. Therap.,116: 317 (1956).Google Scholar
  71. 71.
    Blake, M. W. &Perlman, P. L. Metabolism of the Ultrashort-Acting Thiobarbiturate Methitural (Neraval). J. Pharmacol. & Exper. Therap.,117: 287 (1956).Google Scholar
  72. 72.
    Greisheimer, E. M.et al. Cardiovascular Responses to Several Ultra Short Acting Barbiturates. Anesthesiology,17: 385 (1956).PubMedCrossRefGoogle Scholar
  73. 73.
    Shackman, R., Graber, I. G. &Melrose, D. G. Haemodynamics of Surgical Patient under General Anaesthesia. Brit. J. Surg.,40: 193 (1952).PubMedCrossRefGoogle Scholar
  74. 74.
    Lee, G. de J., Churchill-Davidson, H., Miles, B. E. &de Wardener, H. E. Circulatory Effects of Prolonged Light Anaesthesia in Man. Clin. Sc.,12: 169 (1953).Google Scholar
  75. 75.
    Etsten, B. &Li, T. H. Hemodynamic Changes during Thiopental Anesthesia in Humans Cardiac Output, Stroke Volume, Total Peripheral Resistance and Intrathoracic Blood Volume. J. Clin. Investigation,34: 500 (1955).CrossRefGoogle Scholar
  76. 76.
    Price, H. L. &Helrich, M. The Effect of Cyclopropane, Diethyl Ether, Nitrous Oxide, Thiopental and Hydrogen Ion Concentration on the Myocardial Function of the Dog Heart-Lung Preparation. J. Pharmacol. & Exper. Therap.,115: 206 (1955).Google Scholar
  77. 77.
    O’Herlihy, D. B., Nishimura, N., Little, D. M., &Tovell, R. M. The Clinical Usage of Neraval. Canad. Anaesth. Soc. J.,3: 326 (1956).CrossRefGoogle Scholar
  78. 78.
    Shackman, R., Graber, G. I. &Redwood, C. Oxygen Consumption and Anaesthesia. Clin. Sc.,10: 219 (1951).Google Scholar
  79. 79.
    Lynn, R. B., Sancetta, S. M., Simeone, F. A. &Scott, R. W. Observations on the Circulation in High Spinal Anesthesia. Surgery,32: 195 (1952).PubMedGoogle Scholar
  80. 80.
    Sancetta, S. M., Lynn, R. B., Simeone, F. A. &Scott, R. W. Studies on Hemodynamic Changes in Humans following Induction of Low and High Spinal Anesthesia. Circulation,6: 559 (1952).PubMedGoogle Scholar

Copyright information

© Canadian Anesthesiologists 1957

Authors and Affiliations

  • Allen B. Dobkin
    • 1
  • Gordon M. Wyant
    • 1
  1. 1.Department of AnaesthesiaUniversity of Saskatchewan College of Medicine and University HospitalSaskatoonCanada

Personalised recommendations