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Avertin basal anesthesia
AVERTIN BASAL ANESTHESIA CLINICAL PRELIMINARY
REPORT
OBSERVATIONS
BASED UPON A STUDY
OF 80 CASES*
FRANCIS G. SPEIDEL, M.D. WASHINGTON, D. C.
A
BOUT three years ago there was kidneys, obesity, acidosis, cachexia, diaintroduced abroad a new agent, betes, anemia, shock, hemorrhage and in known as avertin or tribromethanoh other conditions rendering the patient a poor risk, avertin was used in Iess than the for the induction of genera1 anesthesia by recta1 administration. At present there is a average doses, if at aI1. On the other hand, a weaIth of German Iiterature on the subject, somewhat Iarger dosage was required by and severa papers have recentIy appeared chiIdren, young aduIts, persons of the in EngIish medica journaIs. sthenic muscuIar type, aIcohoIics, hypersensitive patients, and those suffering The chemistry, pharmacoIogy, dosage and technic of administration have been from acute abdominal conditions. In genadequateIy discussed. The purpose of this eraI, therefore, individuaIs that are usuaIIy paper is to report my experience in a difIicuIt to anesthetize by any method, Iimited number of cases in which approxireceived the Iarger doses, whiIe the poor mateIy half the dosage necessary for risks, the eIderIy or feebIe, and those with surgica1 anesthesia was empIoyed. The Iow resistance were given the smaI1 doses. desired degree of anesthesia was attained Many other factors were considered, such by the suppIementa1 use of inhaIation as the amount of preIiminary morphine anesthesia. Avertin shouId, in my opinion, medication, probabIy duration and extent be regarded soIeIy as a basa1 anesthetic, of operation, the possibility of profound the dosage being caIcuIated for the indishock or hemorrhage ensuing, the ski11 vidua1 patient so that a Iight narcosis, in of the operator. In fact, it was beIieved itseIf harmIess, is induced. This degree of necessary to consider every eventuality, narcosis assures to the patient practicaIIy since pharmacoIogicaIIy avertin is a cerea11 of the advantages that can be obtained bra1 depressant. If exhaustion occurs from by this method, while any disadvantages any cause, the depression of circuIation it may possess are minimized. ControI of and respiration produced by excessive anesthesia is preserved by the suppIedoses of avertin becomes cIinicaIIy evident; menta1 use of the inhaIation anesthesia. hence the use of a smaI1 dosage in order to This permits remain we11 within the Iimits of safety. the maintenance of any The advantages of avertin anesthesia are desired degree of anesthesia, which may be decreased at wiI1 to the point of the initia1 many. The technic of administration is simpIe. There is an easy and pIeasant stage Iight narcosis. The best index as to the additiona anesthesia required is the paof induction. The patient soon becomes drowsy and faIIs into a deep sIeep with no tient himself. Many of the undesirabIe characteristics of inhaIation anesthesia are unpIeasant sensations; Ioss of consciousness modified or eIiminated by the use of this is usuaIIy compIete in ten minutes. The stage of recovery is equaIIy caIm, and many method of combined anesthesia. patients require IittIe or no postoperative The dosage of avertin used varied from morphine medication, since the hypnotic 30 mg. to IOO mg. per kiIo. of body weight, the average being 80 mg. Many factors effect of the drug wears off quite sIowIy. Avertin is administered to the patient in influenced seIection of the dosage. In his room, in which he goes to sIeep and extensive invoIvement of the Iiver or * Submitted for publication, &larch 8, 1930. 73
74
American Journal of Surgery
SpeideI-Avertin
Iater awakes, so that he remains unaware of the journey to and from the operating room. There is no stage of excitement or of muscuIar rigidity. The maximum narcotic effect is attained in from twenty to thirty minutes. Even when the dose is so smaI1 that consciousness is partiaIIy retained, the entire menta1 outIook is aItered, apprehension is eIiminated, and Iittle if anything is remembered, because of the characteristic retrograde amnesia. The individua1 variations in susceptibiIity are as pronounced with avertin as with other anesthetics. Withdrawa is impracticabIe. The degree of narcosis obtained with it determines the required amount of gas or ether, which may be augmented safeIy to the desired IeveI of anesthesia, and Iater rapidIy withdrawn. The combination of avertin with inhalation anesthesia seems to produce results unattainabIe with a single genera1 anesthetic agent, and compIies with Lundy’s principIe of a baIanced anesthesia. It is possibIe to vary wideIy the percentage of oxygen in the gaseous mixture. For the more extensive intra-abdomina1 operations, ether was preferred to gas. In their influence upon the rate and amplitude of respiration, ether and avertin, in moderate amounts, are direct opponents, but both act in the same direction in securing anesthesia. With ethyIene the respirations are IikeIy to be sIow and shaIIow; with nitrous oxide, more rapid and deeper; with ether, the rate and depth are also increased. With patients having a tendency to cyanosis, not of mechanica origin, ether given by the drop method on the open mask acts as a respiratory stimuIant, as does carbon dioxide and oxygen. Cyanosis does not necessariIy indicate either an excessive degree of anesthesia or a mechanica1 obstruction. In rare instances, it may be due to direct action of avertin on the respiratory center and may be present with anesthesia insuffIcient for surgica1 purposes. Carbon dioxide and oxygen act well as a respiratory stimuIant in Iight anesthesia and increase bIood pressure,
Anesthesia
JULY, IWO
but are Iess effective after anesthesia deepens. The transient depression of respiration and circuIation is aIso relieved by such operative manipulations as incision of skin, expIoration of abdomen, etc. Most patients do as we11 without as with morphine, which acts simiIarIy upon the respiratory center as avertin. For this reason, patients who receive both may 0ccasionaIIy manifest severe respiratory depression. AccordingIy, avertin shouId not be given after heavy preIiminary morphine medication. The systolic pressure may drop about 13 mm., then ascend sIowIy almost to its previous IeveI, which is maintained unless influenced by other factors. In avertin narcosis the masseter muscIes relax earIy and remain so for a Iong period. SaIivation and bronchia secretions are inhibited. When avertin is used as a basa1 anesthetic, the vomiting and respiratory spasm sometimes provoked by surgica1 procedures are absent. In fact, the patients cannot be made to vomit, the probabIe reason being that the function of the vomiting center is suspended. Recovery of the function of the vomiting center is gradua1 and too Iate after the operation to cause postoperative vomiting. However, if the nature of the operation or the condition of the patient is such as to exert a continuous stimuIus upon the center, vomiting may recur after ten or tweIve hours; this has happened after some intestina1 operations, gastroenterostomy or choIecystectomy, and after operation for ruptured appendix with peritonitis, etc. Some degree of muscuIar rigidity is often present when nitrous oxide is used, especiaIIy on cIosure of the abdomen, but with ether in smaI1 amounts relaxation is exceIIent. During an upper abdomina1 operation, if muscuIar rigidity and anoxemia occur due to tra.ction or manipuIation, no hesitancy need be feIt in using ether to overcome this condition; it acts advantageousIy in deepening the respirations, reIaxing the abdomina1 muscIes and improving the patient’s coIor.
NEW SERIES Var.. IX, No. I
SpeideI-Avertin
I have observed in ad&s who are difficult to anesthetize (particuIarIy men of muscuIar physique) and in one chiId of eIeven years, a convuIsive paroxysm upon withdraw1 of the suppIementa1 gas anesthetic. The cIinica1 manifestations are those of a severe chiI1 with rigidity of the abdomina1 muscles, opisthotonos, spastic contraction of the arms and cIenching of the jaws. The attack is anaIogous to the recovery of the deep reflexes foIIowing other anesthetics and, while it is somewhat aIarming, passes off in a short time and need not cause anxiety. It indicates that the patient is IikeIy to recover from the anesthetic sooner than usuaI. With one exception, it was not noted when ether was used; in fact, a few breaths of ether on the open mask wiI1 relax the spasm. RareIy does a patient during recovery become excited; a hypodermic of morphine wil1 quiet such a patient and enabIe him to secure several hours of sleep. CIinicaI and pharmacoIogica1 observations indicate that the period of anesthesia with avertin may be shortened, and bIood pressure and respiration improved by the This use of caffeine sodium benzoate. drug has proved effective in interrupting the narcosis in Iaboratory animaIs, and at present seems the most promising for this purpose. It is probabIy useIess to give Iess than 736to 15 grains of caffeine sodium benzoate to any patient requiring stimuIation; it is safe to use Iarge doses in such cases. In moderateIy severe hyperthyroid types, the average dosage of 80 mg. per kiIo appears to be we11 toIerated. In my opinion, its use is especiaIIy indicated in this and aIIied conditions. However, if the surgeon desires to test the phonation during the operation, the dosage of avertin shouId not exceed 60 mg. per kiIo when supplemented with gas. This wil1 usuahy secure the desired resuIts. In ophthaImic surgery or whenever the patient must remain absoIuteIy quiet, ether is preferabIe to gas as a suppIementa1 anesthetic.
Anesthesia
American Journal of Surgery
75
Patients who are difhcuh to anesthetize with gas, will respond more easiIy to avertin and gas; the administration of the Iatter may be varied within wide Iimits, without fear of vomiting or respiratory spasm. When avertin is suppIemented with ether, the stage of excitement is absent, muscuIar rigidity is often so transient as to be hardly noticeabIe, and saIivation or bronchia secretion faiIs to occur. A sIow reguIar drop by the open method is suff~cient in most cases. UsuaIIy, 0nIy a smaI1 quantity is necessary. When satisfactory relaxation has been secured, the ether may often be discontinued, or a smaI1 amount may again be administered just before cIosure of the abdomen. ReIaxation, once obtained, Iasts for an appreciabIe interval after the withdrawa of ether. If ether is to be used as the suppIementa1 anesthetic, the dose of avertin may generaIIy be reduced. During the stage of recovery, which may Iast from one to three hours, the patient shouId be watched continuousIy by an attendant. As mentioned before, the masseter muscIes are reIaxed, the tongue and jaw dropped, and the pharyngea1 refIexes diminished; faiIure to insure an open airway at a11 times may resuIt in asphyxia. To prevent respiratory difhcuhy from mechanica obstruction, an airway may be inserted as soon as the pharyngea1 reffex is aboIished, and Ieft in place during operation and the postoperative period. REFERENCES In addition to the bibIiography suppEed by A. Spiegel (AM. J. SURG., ,8: 97, x930), the following may be of interest: KILLIAN, H. Zatralbl. f. Cbir., 54: 1997, 1927. STRAUB,W. Miincben. med. Wcbnscbr.. 75: 1279, 1928. WYMER, I., and Fuss, H. Deutscbe Z&r. f. Cbir., 21 I : 281, 1928. BENDER,K. Beitr. z. Min. Cbir.. 143: 599, 1928. STEHLE,R. Canad. M. A. J., xg: 706, 1928. WELSCH, A. Arch. f. exper. Path. u. Pbarmakol., 139: 30% 1929. EDWARDS,G. Brit. M. J., 2: 713, 1929. SPIEGEL,A. AM. J. SURG., 8: 97, 1930.
REPORT
OBSERVATIONS
BASED UPON A STUDY
OF 80 CASES*
FRANCIS G. SPEIDEL, M.D. WASHINGTON, D. C.
A
BOUT three years ago there was kidneys, obesity, acidosis, cachexia, diaintroduced abroad a new agent, betes, anemia, shock, hemorrhage and in known as avertin or tribromethanoh other conditions rendering the patient a poor risk, avertin was used in Iess than the for the induction of genera1 anesthesia by recta1 administration. At present there is a average doses, if at aI1. On the other hand, a weaIth of German Iiterature on the subject, somewhat Iarger dosage was required by and severa papers have recentIy appeared chiIdren, young aduIts, persons of the in EngIish medica journaIs. sthenic muscuIar type, aIcohoIics, hypersensitive patients, and those suffering The chemistry, pharmacoIogy, dosage and technic of administration have been from acute abdominal conditions. In genadequateIy discussed. The purpose of this eraI, therefore, individuaIs that are usuaIIy paper is to report my experience in a difIicuIt to anesthetize by any method, Iimited number of cases in which approxireceived the Iarger doses, whiIe the poor mateIy half the dosage necessary for risks, the eIderIy or feebIe, and those with surgica1 anesthesia was empIoyed. The Iow resistance were given the smaI1 doses. desired degree of anesthesia was attained Many other factors were considered, such by the suppIementa1 use of inhaIation as the amount of preIiminary morphine anesthesia. Avertin shouId, in my opinion, medication, probabIy duration and extent be regarded soIeIy as a basa1 anesthetic, of operation, the possibility of profound the dosage being caIcuIated for the indishock or hemorrhage ensuing, the ski11 vidua1 patient so that a Iight narcosis, in of the operator. In fact, it was beIieved itseIf harmIess, is induced. This degree of necessary to consider every eventuality, narcosis assures to the patient practicaIIy since pharmacoIogicaIIy avertin is a cerea11 of the advantages that can be obtained bra1 depressant. If exhaustion occurs from by this method, while any disadvantages any cause, the depression of circuIation it may possess are minimized. ControI of and respiration produced by excessive anesthesia is preserved by the suppIedoses of avertin becomes cIinicaIIy evident; menta1 use of the inhaIation anesthesia. hence the use of a smaI1 dosage in order to This permits remain we11 within the Iimits of safety. the maintenance of any The advantages of avertin anesthesia are desired degree of anesthesia, which may be decreased at wiI1 to the point of the initia1 many. The technic of administration is simpIe. There is an easy and pIeasant stage Iight narcosis. The best index as to the additiona anesthesia required is the paof induction. The patient soon becomes drowsy and faIIs into a deep sIeep with no tient himself. Many of the undesirabIe characteristics of inhaIation anesthesia are unpIeasant sensations; Ioss of consciousness modified or eIiminated by the use of this is usuaIIy compIete in ten minutes. The stage of recovery is equaIIy caIm, and many method of combined anesthesia. patients require IittIe or no postoperative The dosage of avertin used varied from morphine medication, since the hypnotic 30 mg. to IOO mg. per kiIo. of body weight, the average being 80 mg. Many factors effect of the drug wears off quite sIowIy. Avertin is administered to the patient in influenced seIection of the dosage. In his room, in which he goes to sIeep and extensive invoIvement of the Iiver or * Submitted for publication, &larch 8, 1930. 73
74
American Journal of Surgery
SpeideI-Avertin
Iater awakes, so that he remains unaware of the journey to and from the operating room. There is no stage of excitement or of muscuIar rigidity. The maximum narcotic effect is attained in from twenty to thirty minutes. Even when the dose is so smaI1 that consciousness is partiaIIy retained, the entire menta1 outIook is aItered, apprehension is eIiminated, and Iittle if anything is remembered, because of the characteristic retrograde amnesia. The individua1 variations in susceptibiIity are as pronounced with avertin as with other anesthetics. Withdrawa is impracticabIe. The degree of narcosis obtained with it determines the required amount of gas or ether, which may be augmented safeIy to the desired IeveI of anesthesia, and Iater rapidIy withdrawn. The combination of avertin with inhalation anesthesia seems to produce results unattainabIe with a single genera1 anesthetic agent, and compIies with Lundy’s principIe of a baIanced anesthesia. It is possibIe to vary wideIy the percentage of oxygen in the gaseous mixture. For the more extensive intra-abdomina1 operations, ether was preferred to gas. In their influence upon the rate and amplitude of respiration, ether and avertin, in moderate amounts, are direct opponents, but both act in the same direction in securing anesthesia. With ethyIene the respirations are IikeIy to be sIow and shaIIow; with nitrous oxide, more rapid and deeper; with ether, the rate and depth are also increased. With patients having a tendency to cyanosis, not of mechanica origin, ether given by the drop method on the open mask acts as a respiratory stimuIant, as does carbon dioxide and oxygen. Cyanosis does not necessariIy indicate either an excessive degree of anesthesia or a mechanica1 obstruction. In rare instances, it may be due to direct action of avertin on the respiratory center and may be present with anesthesia insuffIcient for surgica1 purposes. Carbon dioxide and oxygen act well as a respiratory stimuIant in Iight anesthesia and increase bIood pressure,
Anesthesia
JULY, IWO
but are Iess effective after anesthesia deepens. The transient depression of respiration and circuIation is aIso relieved by such operative manipulations as incision of skin, expIoration of abdomen, etc. Most patients do as we11 without as with morphine, which acts simiIarIy upon the respiratory center as avertin. For this reason, patients who receive both may 0ccasionaIIy manifest severe respiratory depression. AccordingIy, avertin shouId not be given after heavy preIiminary morphine medication. The systolic pressure may drop about 13 mm., then ascend sIowIy almost to its previous IeveI, which is maintained unless influenced by other factors. In avertin narcosis the masseter muscIes relax earIy and remain so for a Iong period. SaIivation and bronchia secretions are inhibited. When avertin is used as a basa1 anesthetic, the vomiting and respiratory spasm sometimes provoked by surgica1 procedures are absent. In fact, the patients cannot be made to vomit, the probabIe reason being that the function of the vomiting center is suspended. Recovery of the function of the vomiting center is gradua1 and too Iate after the operation to cause postoperative vomiting. However, if the nature of the operation or the condition of the patient is such as to exert a continuous stimuIus upon the center, vomiting may recur after ten or tweIve hours; this has happened after some intestina1 operations, gastroenterostomy or choIecystectomy, and after operation for ruptured appendix with peritonitis, etc. Some degree of muscuIar rigidity is often present when nitrous oxide is used, especiaIIy on cIosure of the abdomen, but with ether in smaI1 amounts relaxation is exceIIent. During an upper abdomina1 operation, if muscuIar rigidity and anoxemia occur due to tra.ction or manipuIation, no hesitancy need be feIt in using ether to overcome this condition; it acts advantageousIy in deepening the respirations, reIaxing the abdomina1 muscIes and improving the patient’s coIor.
NEW SERIES Var.. IX, No. I
SpeideI-Avertin
I have observed in ad&s who are difficult to anesthetize (particuIarIy men of muscuIar physique) and in one chiId of eIeven years, a convuIsive paroxysm upon withdraw1 of the suppIementa1 gas anesthetic. The cIinica1 manifestations are those of a severe chiI1 with rigidity of the abdomina1 muscles, opisthotonos, spastic contraction of the arms and cIenching of the jaws. The attack is anaIogous to the recovery of the deep reflexes foIIowing other anesthetics and, while it is somewhat aIarming, passes off in a short time and need not cause anxiety. It indicates that the patient is IikeIy to recover from the anesthetic sooner than usuaI. With one exception, it was not noted when ether was used; in fact, a few breaths of ether on the open mask wiI1 relax the spasm. RareIy does a patient during recovery become excited; a hypodermic of morphine wil1 quiet such a patient and enabIe him to secure several hours of sleep. CIinicaI and pharmacoIogica1 observations indicate that the period of anesthesia with avertin may be shortened, and bIood pressure and respiration improved by the This use of caffeine sodium benzoate. drug has proved effective in interrupting the narcosis in Iaboratory animaIs, and at present seems the most promising for this purpose. It is probabIy useIess to give Iess than 736to 15 grains of caffeine sodium benzoate to any patient requiring stimuIation; it is safe to use Iarge doses in such cases. In moderateIy severe hyperthyroid types, the average dosage of 80 mg. per kiIo appears to be we11 toIerated. In my opinion, its use is especiaIIy indicated in this and aIIied conditions. However, if the surgeon desires to test the phonation during the operation, the dosage of avertin shouId not exceed 60 mg. per kiIo when supplemented with gas. This wil1 usuahy secure the desired resuIts. In ophthaImic surgery or whenever the patient must remain absoIuteIy quiet, ether is preferabIe to gas as a suppIementa1 anesthetic.
Anesthesia
American Journal of Surgery
75
Patients who are difhcuh to anesthetize with gas, will respond more easiIy to avertin and gas; the administration of the Iatter may be varied within wide Iimits, without fear of vomiting or respiratory spasm. When avertin is suppIemented with ether, the stage of excitement is absent, muscuIar rigidity is often so transient as to be hardly noticeabIe, and saIivation or bronchia secretion faiIs to occur. A sIow reguIar drop by the open method is suff~cient in most cases. UsuaIIy, 0nIy a smaI1 quantity is necessary. When satisfactory relaxation has been secured, the ether may often be discontinued, or a smaI1 amount may again be administered just before cIosure of the abdomen. ReIaxation, once obtained, Iasts for an appreciabIe interval after the withdrawa of ether. If ether is to be used as the suppIementa1 anesthetic, the dose of avertin may generaIIy be reduced. During the stage of recovery, which may Iast from one to three hours, the patient shouId be watched continuousIy by an attendant. As mentioned before, the masseter muscIes are reIaxed, the tongue and jaw dropped, and the pharyngea1 refIexes diminished; faiIure to insure an open airway at a11 times may resuIt in asphyxia. To prevent respiratory difhcuhy from mechanica obstruction, an airway may be inserted as soon as the pharyngea1 reffex is aboIished, and Ieft in place during operation and the postoperative period. REFERENCES In addition to the bibIiography suppEed by A. Spiegel (AM. J. SURG., ,8: 97, x930), the following may be of interest: KILLIAN, H. Zatralbl. f. Cbir., 54: 1997, 1927. STRAUB,W. Miincben. med. Wcbnscbr.. 75: 1279, 1928. WYMER, I., and Fuss, H. Deutscbe Z&r. f. Cbir., 21 I : 281, 1928. BENDER,K. Beitr. z. Min. Cbir.. 143: 599, 1928. STEHLE,R. Canad. M. A. J., xg: 706, 1928. WELSCH, A. Arch. f. exper. Path. u. Pbarmakol., 139: 30% 1929. EDWARDS,G. Brit. M. J., 2: 713, 1929. SPIEGEL,A. AM. J. SURG., 8: 97, 1930.