Doc 0000021810

- .... --·~ .. -... --..--~·--- -.. ~ .. --·-------- -----~-..... --'-- -.... · .• ; April Z6, 1966 \ Dear Dr. The program to evaluate various electrical combinations !or their potential for producin~ anesthesia has been designed and is enclosed. Art.' e!lort has been made to include as many of the parameters we previo1.1sly discus s.ed and work out the details as soon as possible. Aiter your review of the program, deletions or additions ca.n be made if necessary. This study does not go into the specific details of the basic principles as mucil as I would like to investigate at some time. I think it best to look at that phase of study alter we complete this study and know the current combination that gives the best results. I would ~ticipate doing some mic roe1ectrode work !or more specific information on the amount of current in specific brain areal at a later date. I will complete ny training program ;~t This will work very well with yo', July 1 • June 30 fiscal year, I had anticipated being committed until S..!ptember l, but have been able to arrange to start on this progrant July lst instead. One part o£ the budget was somewhat uncertain. This is in regard I to the bstitutional overhead. Alter checking with the people at . I find that the overhead chargu are 20o/o on N. I. H. or N. S. F. type grants or 40o/o of salaries on other types. Since you mentioned a number of groups in Washington were interested in the program, I have assumed that all involved fit into the same bracket. ... ,. Or. • 2 • April 2.6. 1966 Our plans are to devote full time to this ;?rogram. The only exception to this :!or which I would lilt.e approval is to spend 9·1Z days per year to pro vide the necessary surgical and anesthetic procedures for the kidney transplant program at the ...... ···. · l ·- · - ··-··· I Electroanesthesia is used in these ·p~ocedure.s on twin calves and the very valuable data on electreanesthesia in twins of known com~ patibility would be included in the reports •. No grant funds from the - ·· t1 program would be 1ued in the kidney program. 1 In discussing the anesthesia program with Dr. it was of con· siderable interest to r.ote the suggested possibility of h\!.lllan The image is a graphic with text overlaid on a background that depicts a vault door. There are no photographs of people, locations, equipment, or subjects. There are no handwritten annotations, signatures, or marginalia. No official stamps, forms with filled-in fields, diagrams, schematics, organizational charts, or tables are present. There are no visible redactions or obscured content, nor any visual evidence of experimental procedures, equipment, or facilities. The image primarily serves as an introductory or informational graphic for "The Black Vault," an online database of declassified government documents, specifically highlighting the MKULTRA/Mind Control Collection. The page contains a typewritten letter, dated April 26, 1966, addressed "Dear Dr." The main body of the text discusses a program to evaluate electrical combinations for anesthesia and outlines plans for a study and its budget. There is a handwritten annotation "(241)" in a circle at the bottom right corner, and a circular black mark near the top center of the page. The upper left corner has a section with illegible dashed lines, and the right side of the page has faint vertical lines and a diagonal line across the middle. The document appears to be a standard letter format, with no visual evidence of experimental procedures, equipment, or facilities. in twins of known com~ patibility would be included in the reports •. No grant funds from the - ·· t1 program would be 1ued in the kidney program. 1 In discussing the anesthesia program with Dr. it was of con· siderable interest to r.ote the suggested possibility of h\!.lllan application aftez: completion of the animal program. I felt you would like to know of this in the event it is desirable to co-ordinate a human experimental program at a later date. Let me know if I need to make any cha.ng-es in the program enclosed. I am looking forward to getting started on our program and see if we can't find out what the potential of electroanesthesia really is. Thank you for your continued interest. Yours truly, .\ "l . f Enclosure --CO-------------------~----~ c~ ---------- •' PROJECT PROPOSAL Title: 11Effects of Combination.'i of Waveforms and Frequencies of Electrical Curre?ts Applied to the Head to Produce Anes:hesia" ' Investigator: J Department and Location: Director: Objectives and Procedures: I. Determination of the most effective combinations of electrical current producing anesthesia A. Combinations of sine, saw tooth, square, triiLllgle. white noise, pulse D .. C. and D. C. signals will be employe:! irl combinations to achieve this objective. Both two ~nd three wave combinations will be employed with variable frequencies. Bc.sed on the published experience o£ others and my own personal experience, it is not anticipated that anesthesia will be produced by all currents. Some will produce convulsions, tonic muscle spasms, and/or respiratory~ cardiac distress without anesthesia. From published data. these complications bave been more evident with certain waveforms and curz ent combinations than with others. This study proposes to de· termine i.n a systematic fashion which wave-forms and !requency combinations produce acceptable anesthesia with minimal undesirable side effects. The equipment has been design: d to permit investi• gation of over two hundred combinations of waveforms and frequencies which will be rated according to desirable and undesirable charac· teriHics produced. B. Combination waves will be applied to the heac! by two techniques: 1. Summation of the current before it enters the head. (Two electrodes-American technique) z. Summatim of the current in the bead. (Four and six electrode combinations with separate leads to the generators producing the combination·Russian technique). Combinations o~ waveforms and frequencie!i which are obviously not satisfactory due to severe respiratory or circulatory distress, convulsions, cardiac difficulties or other unforeseen problems (Two electrodes-American technique) z. Summatim of the current in the bead. (Four and six electrode combinations with separate leads to the generators producing the combination·Russian technique). Combinations o~ waveforms and frequencie!i which are obviously not satisfactory due to severe respiratory or circulatory distress, convulsions, cardiac difficulties or other unforeseen problems will be recorded as such, and will not be evaluated more extensively. .. ......_ ..... ,.. .._ ,._ _. . ___ .• _____ ... _ .. ~----.... _.-- ·-----------___ ........_..... _____ ·---~---.,..__.. ........ _ .... _,....__:__,_,_ ......L •*"'-~-•·. .. -··~4~~·~ o •• .. • 2 - Combinations which show promise for' anesthesia will be evaluated further as outlined in objective II. II. n.e effect of anesthetic currents on respiration. circulation and depth of anesthesia When a combination of electrical currents appears to have potential as an anesthetic agent. the following procedures will be followed. Pre anesthet:.,; measurement of all pertinent parameters will be made (see typical ex-perimen·~ below). The cardiac ani respirato :y alterations will be monitored during and after induction. If successful, a surgical procedure will be carried out to evaluate ~e effectiveness of the com bination of current to produce anesthesia and muscle relaxation. Since it is possible with electrical current to produce satisfactory anesthesia in portions of the body while inadequate in others, six locations will be considered !or surgical procedures {simple cut down}. These are head. neck, limbs, bones or s·kin, thoracic, urogenital, superficial abdominal, and deep abdominal. Monitoring will continue dul"ing surgical procedun~Si. ·After operation, current will be shut o!f a.Ld the recovery behavior noted. Blood samples will be drawn before, duri~ and a!ter anesthesia a.n4 tb.e recovery pattern of cardiac and re5piratory changes will be followed foro Z4 hours. Blood pressure measurement will be made by direct cannula tion of the femoral artery and this will pennit monitoring of heart rat~ as well, Respiration will be measured by pneumograph and Lead n of the electrocardiogram will be monitored before and alter application of tae current. Dogs will not receive muscle relaxants nor oxygen nor will they be intubated, These will be deliberately avoided so that muscle activity a.I+d respiratory depression may be observed, when they occur. This also allows a full response to pain during iUrgery if there is insufficient anesthesia. m. Determination of the total amperage of each combination and correlation with effectiveness in producing anesthesia. This will be done to determine the The page is a typed letter with some handwritten additions. The typed portion discusses a program involving kidney transplants and electroanesthesia in calf twins, with a potential for human application. There is a "CLASSIFIED" stamp, partially visible at the top. There are also handwritten annotations in the lower portion of the page, including a salutation and what appears to be additional notes about the program's readiness and approval. No photographs, diagrams, or other visual elements are present. that muscle activity a.I+d respiratory depression may be observed, when they occur. This also allows a full response to pain during iUrgery if there is insufficient anesthesia. m. Determination of the total amperage of each combination and correlation with effectiveness in producing anesthesia. This will be done to determine the combination te'1uiring minimal current for anesthesia.. The current and voltage will be measured with a milliam~ meter and a true r, m. s. voltmeter, The waveforms will be monitored with an oscilliscope and the waveform combinations will be photographe~ from the scope to record them accurately, Measurement equipment will be attached to the anesthesia generator output, .. - 3 - rtf. Determination of the "shape" of the electrical field produced by the Current combination This will be determined by connecting the ~ecording equipment to implanted macroelectro.des and is designed to indicate the distribution of the curren-.. within the brain and its intensity. For this study, six chronic electrodes will be placed in selected locations within the brainG Dogs will then be subjected to currents of waveform and frequency combinations known to produce anesthesia. Recordings will be made using the same equipment required in Section Ill. These dogs will be used only to measure the shape of the electrical f~eld. Since these dogs can be used repeacedly, we plan to keep five dogs with chr~nically implanted electrodes at all times. The use of these same animals for s-!veral combinations of currents will reduce the error in measurement between animals. These dogs will be prepared early during !he period required to obtain the necessary equipment and pet-sonnet to initiate the other aspects of the project. Metallic-nylon electrodei will be implanted through small trephines in the sh.-ull during general anesthesia. The micro• manipulator will be used for positioning electl'odes with neurosurgic~ assistance. V. TypiCal Experiment: Planned technique fer evalu~tion of each combi nation A, Waveform combination and frequency will be selected and equip ment adjusted for operation. B, The following measurements will be ma:de on normal animals: 1. Heart r~e. and ECG. z. Respiratory rate. 3. Rectal temfE!l" ature. 4. Arterial blood gase;; (pCOz, pOz) and pH. . s. Notation of general physical condition, activity and alertness. c. Animal will then be prepared for a.pplication of current. 1. Preparation of electrode sites (Bitempor;.,l or frontal-occipital). 2.. Cannulation of femoral artery wi':h local anesthesia. 3. Flacement of electrodes (electrode will be needle or plate This document is a declassified MKUltra project proposal and appears to be a typed report. There are no photographs, diagrams, or tables. There are a few handwritten annotations, including underlines on some text and a curved line under the title "PROJECT PROPOSAL." There are no official stamps or markings visible. The document is a form with fields for "Title," "Investigator," "Department and Location," and "Director," but only the "Title" field has been filled in. The rest of the document is structured with numbered and lettered sections detailing the "Objectives and Procedures" for the proposed experiment. There is no visual evidence of experimental procedures, equipment, or facilities. This page is a typed document with some minor formatting elements. It contains a numbered header "-2-" and two distinct sections titled "II. The effect of anesthetic currents on respiration, circulation and depth of anesthesia" and "III. Determination of the total amperage of each combination and correlation with effectiveness in producing anesthesia". There are no photographs, handwritten annotations, signatures, stamps, forms, diagrams, tables, or redactions visible on this page. The document appears to be a technical or experimental procedure description, focusing on anesthetic methods and measurements. (pCOz, pOz) and pH. . s. Notation of general physical condition, activity and alertness. c. Animal will then be prepared for a.pplication of current. 1. Preparation of electrode sites (Bitempor;.,l or frontal-occipital). 2.. Cannulation of femoral artery wi':h local anesthesia. 3. Flacement of electrodes (electrode will be needle or plate depending on D. C. or A. C. operation}. .· - 4 - D. Connect leads and apply current. l. Record response (muscle movements, struggling, excitement, salivation, etc.). Z. Monitor blood pressure, ca~<!iac rate and respiratory rate. 3. Sample arterial blood for PCOz. POz. pH when ~duction is completed or abandoned. E. Determine depth of anesthesia by tail clamping, corneal reflexes, swallowing reflexes. lf no anesthesia, abandon. i. If anesthesia present, proceed to cut downs at various sites. Monitoring will continue throughout operation. Responses to incision in various areas and ma.oipulatiou will be noted. G. R~sponse to remo~al of current from the head will be recorded and all parameters remeasured. H~ Twelve and Z4-hour post-operative observations will be made. L Determination of the Cl.U'rent and voltage levels will be made a!ter induction, during operation and just prior to termination of current 1 application. J. If satisfactory anesthesia obtained, shape of electrical field 'will be determined in. dogs with chronically implanted electrodes. The number o£ combinations of currents and waveforms to be evaluated and the need fo:r numbers of animals sufficient for proper statistical analysis make it necessary to use a large number of dogs. Each dog as will be used as extensively possible and yet yield accurate results. It is anticipated that so:.me losses by death will occur, especially since many current combinations have never before been attempted. When possible, dogs will be reused as often as practical. To obtain a definitive answer for each current we believe 4 dogs must be studied before abandoning the combinat\on• . Com':)inations which give promise of s~tisfact-:>ry anesthesia will be studied more extensively whenever in-dicated. Responses noted during the entire procedure will be recorded in terms ~f depth of anesthesia and duration of current application. The investigator and technicians will spend full time on the project and will have no other activities. A two-year period is considered the minimal time to complete the program, lt is anticipated that two months will be required to assemble the equipment and personnel necessary r_,r full scale operation. ·-----··--•• ---·-·'"•"r-·-· ...... ,-.. -.-.--_........_._.-. .. ...._._ ... - ... the project and will have no other activities. A two-year period is considered the minimal time to complete the program, lt is anticipated that two months will be required to assemble the equipment and personnel necessary r_,r full scale operation. ·-----··--•• ---·-·'"•"r-·-· ...... ,-.. -.-.--_........_._.-. .. ...._._ ... - ... """'"•·-·"• • ,__ ....... .----·-·-..,,... __ ~-- .. - 5 - Olustra.tiori. of the Method of Determining Waveform Combinations Waveforms A. S~ne E. Random or White Noise B. Square F. D. C. c. Triangle G. D. C. pulse D. Saw Tooth Combinations A+A BtB C:+C D+D E+E F+F G+G A+B BtC C+D D+E E+F F+G A+C BtD CtE D+F £+G A tO BtE CtF D+G A+E B+F C+G A+F B+G A+G Combinations will be summated before and after entering head. Frequencies will also be varied. The same system will be used !or determining triple waveform c.ombinations. .· . ., - 6 - BUDGET PERSONNEL SALARIES Inve .::itigator. Full Time •••• $ o o •• o ••••••• o • • • • • • • • • • Technicians (Z) 1. Assisting with animal procedures Anesthesia and S·o.1rgery z. Laboratory Analysis (Blood gases, etc.) Secretary - part time (SOo/o) Total $ __ ANut~....~. _.T.. .. . .. , . s ,_ 500 dogs @ ,I each $ Board • 5 dogs for 365 days @ • 60/day SOO dogs for ave rage of 3. 5 days @·. 60/ da}i Total EQUIP:MEKT Components for Anesthesia Apparatus: {l) Harrison Lab. Model 865 C for D. C. $ (Z) Universa.l Dynamics Electro-Thesis D. C. pulse generator (3) Hewlett-Packard Model I3380B Sine Wave (4) Hewlett-Packard Model HOOA/3304 Function generator for triangle & sawtooth (5) General Radio Model 1390-B- (a component for random noise) (6) Krohn-Hite Model 31 0-C - Tuneable filter for producing ranges of random noise (7) Interconnecting cables, leads from generators to animals, C')nnected hardware, etc. Sub Total Recording Components: (1) Oscilliscope - To monitor waveforms and observe electrical field in head. Hewlett-Packar·d Model 141 A with Differential Amplifier (1403A), Time base 14ZO A or equivalent $ (Z) Oscilliscope Camera for recording waveforms !or records .. , .,. •._ ,,... • ._.. __. ,,_.,..... .... ~~--r-·--..-••"1 • .--•• ....,,-,.,,._,._ .• ~----- ... ..-... --·-·------....,._,....,.~..,..,...--_._ __ ., -··-••·----... _,.._ • ..-•--- -·-• • .• - 7 - (3) Milliameter - To measure the current afplied to I head and also in brain $ (4) The document page is printed text with no images, handwritten annotations, or official stamps. It is sectioned into Roman numerals IV and V, detailing experimental procedures for determining electrical field "shape" and a "Typical Experiment" protocol. The text describes the implantation of electrodes in dogs and the measurements to be taken during an experiment, including physiological parameters and application of currents. There are no visual elements that directly depict experimental procedures, equipment, or facilities beyond what is described in the text. !or records .. , .,. •._ ,,... • ._.. __. ,,_.,..... .... ~~--r-·--..-••"1 • .--•• ....,,-,.,,._,._ .• ~----- ... ..-... --·-·------....,._,....,.~..,..,...--_._ __ ., -··-••·----... _,.._ • ..-•--- -·-• • .• - 7 - (3) Milliameter - To measure the current afplied to I head and also in brain $ (4) True R. M.S. Voltmeter • To measure the true R. M.S. current, Gives information needed for true electrical power applied to the head. (5) Connections, shipping f Sub Total Micromanipulator !or positioning electrodes $ Electrodes Blood Gas Analysis Equipment: (1) Instrumentation Labs, Micro Analysis System reconunended $ (2) Gases !or Analysis Equipment Surgical Supply Charges: {Includes instrWil! nts, drapes, suture, r-elated su.rgical supplies.) Charges are $ } set per day. It is planned to complete series procedures on days of surgery for more efficiency and economy. We are capable of performing 12-14 sUl"gical pro cedures for the purpose of evaluation of anesthetic levels in the various regions of the body/day. Surgery is plalUled for 170 days. $. Total $ MlSCE LLANEOUS Fhot::>graphy $ Travel Tubing, catheters, drugs Total $ INSTITUTJONAL OVERHEAD 401}'~ o{ Salaries ! Orand Total - lst Year $ 4• ,.40 ·---4--·--·--·-·-c---------L-. ..... ------... _,. ...... -. -----......... ___ , ____ ,....,..,._ ........ , ..... -, -<oH- +••-•"'P"'••-.-.. ·-•••-• .0~ ·-·- < .. • 8 . BUDGET • Znd Year PERSONNEL SALARIES Investigator $ . Technicians 1. l. Secretarial Service • 50,-, of Time Total ANIMALS ... __ .... -- ' 600 dogs (?! ' $ Board·' ,/) .. Total EQUIPlv'LENT i Replacements, extra components for anesthesia l equipment $ Electrodes I Blood gas equipment, electrodes and gases Sur~ical Sup_p~y .c~~rges 'j Total $ !t.USCELLANEOUS ! Photography $ Travel f Drugs, tubing. small equipment Total INSTITUTIONAL OVERHEAD 40% of Salaries ! Grand Total - 2nd Yeu $ - .· .. •, INTRODUCTION A wide range of electrical waveforms have been used on many species 1 of animals and on man since L.e Due made his attempts to produce electro anesthesia in 1902. The most c:ommon types of current used were either direct current with DC pulses, square, triangle, sawtooth, or sine waveforms, or combinations of these. White noise was also introduced in attempts to pro duce better anesthesia, The principal responses detected by a number o£ investigators during the past few years are included. Examples of both desirabl(; and undesirable reactions observed are included. Fabian2 and Hardy 1 This document page is entirely text-based, with no visual elements such as photographs, stamps, annotations, or redactions. It appears to be a typed list of experimental procedures or protocols, numbered and lettered for organization. The layout is structured with distinct sections, suggesting a step-by-step guide or a set of instructions for an experiment involving dogs, anesthesia, and electrical stimulation. The text describes measurements, observations, and decision-making criteria within the experimental context. sawtooth, or sine waveforms, or combinations of these. White noise was also introduced in attempts to pro duce better anesthesia, The principal responses detected by a number o£ investigators during the past few years are included. Examples of both desirabl(; and undesirable reactions observed are included. Fabian2 and Hardy 1 M9 did extensive animal studies and then attempted human app1ications. They used 700 cycle per second sine wave and characteris tically produced strong tonic muscle contractions. The most conspicuous cardiovascular reaction was hypertension and tachycardia, This was associated with a rise in plasJ!la catechol amine levels. Proknged electro~anesthesia had little e!fec t on the b!ood oxygen if the animal was well ventilated. A hyper glycemic response was rec:orded in animals subjec~ed to electro-anesthesia, Geddesl, 4 reported on results in dogs and horses. Direct currer.t with DC pulses was used and hypertension and poor muscle relaxation were charac teristics. He observed cardiac and respiratory arrest in all cases. This was .temporar'( in most cases if the current levels were properly adjusted. However, in his report on applicatior.s in horses, there was a 14 per cent mortality rate due tC' permanent respiratory arrest. Salivation a:"ld hyperthermia were also observed as undesirable side effects in dogs • ----. - . ,,, ······--~··· -·--"'"~----·--~·-·-~--·--------- ,. .• z - ~ Cowing5• 6 reported no abnormalities in the electrocardiogram during electro-a::1esthesia by DC·square wave current in ~ogs. Herir.,lO evaluated the responses and current requirements in dogs using sine, square and triangle waveforms. He concluded that sine wave applications gave the least amount of unwanted side effects. The hypi!:rtension during indue~ tion subsided as anesthesia progressed. Hematologic studies befo. ..· e, during and after electro-anesthesia revealed no significa.nt differences in blood clotting time, packed cell volume, sedimentation rate, her-1oglobin or differential white blood cell count. 11 Klemm • lZ used square wave currents at frequencies up to llOO c.p. s. A relationship between the amount of current required and the frequency of the current was observed in applications to cats. 1 K.."1utson 3·16 conducted most of his work with 700-1500 cycle per second sine wave currents in dogs and man. Hyperglycemia o-:curred during the pass age of electrical currents. Knutson found no evidence o£ brain damage from the current levels used in his experiments, but cites work done by other investigato~s with higher voltage le'.·els which produced hemorrhages in the brain. At the low'ef' l~v.:ls of current This is an otherwise blank page with lines of text at the top. The text is a list of waveforms and their respective combinations and is presented in a table-like format. There is also a small circular ink stamp at the top left corner of the page. The text and stamp strongly suggest that this page is part of a technical document. dogs and man. Hyperglycemia o-:curred during the pass age of electrical currents. Knutson found no evidence o£ brain damage from the current levels used in his experiments, but cites work done by other investigato~s with higher voltage le'.·els which produced hemorrhages in the brain. At the low'ef' l~v.:ls of current applic<l-tion, the principal daneer of brain cell damage was from _inadequate oxygen, due to depression of the respiration by physical interferet;ce from m1,1scle contrae:tions. Knutson controlled convulsions by the use of muscle relaxanu or by adjustments in the current applied to the head. Knutson found that serum potassium, calcium, chlqride and sodium did not change during three hours of continuous electro-anesthesia. Blood urea nitr.ogen levels indicated a decrease in kidney function. .· • 3 • By using techniques of modern ane~thesia, Knutson was able to eliminate or modify the complication;-; of cyanosis, bradycardia, cardiac irrt>gularities and severe muscle contractions, 17 Price reported muscle spasms, elevation in blood pressure and tachycard~a as the principal disadvantages. His experience indicated that children and elderly patients tolerated electro-anesthesia especially well. The responses to electro•anesthesia could indicate potential use in patients with low blood pres sure or bronch~al infections, according to Price. The wave form used was sine wave at 700 cycles per second. Powersl8, 44 reported diverse effects he observed in dogs using 700 c. p. s. since wave current. Current of lOO milliamperes !or one-hal! hour pro duced increases in the hematocrit unless dogs were splenectomized, A significant i.nc~ease in tr.e myocardial contractile force was recorded using a Walton· Btodie strain gauge sutured to the right ventricl~ and recorded on a Model 5~ Crass polygraph. Sances 1 9-Z6 used rectangular electrical wa·1es and made studies on conduction over cortical pathways. Evoked potentials were recorded in Macaque monkeys during electro-anesthesia. With electrical stimulation of the sciatic nerve, the evoked re&ponse recorded from the medial lemniscus • was minimally affected,· that recorded from the nucleus ventralis posterior was mode:ately reduced in amplitude, while the evoked potential recorded from the post central gyrus was abolished. ,• - 4 - 3 Smith Z-J6 used a number oC dii!erent currents in his research. In dogs subjected to 20 milliamperes of DC and 20-30 milliamperes of square wave AC, there was a temporary but consistent cr.ange in amplitude and frequency o£ the EEO. The post-electro-anesthesia EEG pattern returned to normal within 30 minutes. Histo-pathology studies revealed no neuronal changes This page from a declassified CIA document (Doc 0000021810) contains text detailing budget allocations for personnel salaries, animals, and equipment, along with a single dark circular stamp near the top margin. The layout is structured with clear headings and bulleted lists, suggesting a financial or inventory report. Several dollar signs ($) are present, indicating monetary values associated with the listed items, specifically under "PERSONNEL SALARIES" and "ANIMALS," and also by the equipment components on the right side of the "EQUIPMENT" section. There are no photographs, handwritten annotations, or official stamps that would indicate classification or specific handling instructions beyond the existence of the declassified document itself. The visual elements primarily reinforce the organizational structure and financial nature of the information presented in the text. dii!erent currents in his research. In dogs subjected to 20 milliamperes of DC and 20-30 milliamperes of square wave AC, there was a temporary but consistent cr.ange in amplitude and frequency o£ the EEO. The post-electro-anesthesia EEG pattern returned to normal within 30 minutes. Histo-pathology studies revealed no neuronal changes other than agonal swelling, without areas pf hemorrhage or necrosis in the eight brains evaluated. In clinical studies on dogs, respiration was slowed, but the arterial oxygen saturation did not fall below 91 per cent. The pC0 levels did not rise 2 above normal. Body temperature rises were det<Octed, but could be reduced if the animal was not intubated and had the tongue exposed to the air. 37 3 Turbes - 9 used a variety of currents and studied the effects on th~ EEG, reflexes, pain and maintance of electro-anesthesia. Slow induction was found to give a more acceptable physiological state and thus give more reliable results for all parameters evaluated. Fast inductions gave cardio-pulmonary difficulties which were fatal if not treated prompt!}·. 4 3 Van Harreveld 0·4 using 60 cycle currents observed respiratory arrest during inC.uction with 300 milliamperes of current. After this initial period. he reduced the current sufficient to restore respiratic-n. No mention was made of the number o! animals that had permanent respiratory arrest, Increases in blood pressure were observed. The material published by Van Harreveld indi~ cated respiratory difficulties were present through·:)Ut his procedures. .. •' s - Ma