1. TYPES OF OPERATIONS UNDER AA
Since the mid 1970s, major surgery has been done in animals under AA as the sole analgesic agent in many countries in the West. These include France, Germany, Austria, Belgium, USA, Canada and Australia. Workers in Eastern countries such as China, Japan, Taiwan etc have used the method for many years. The animal species involved include horses, mules, donkeys, cattle, sheep, goats, pigs, monkeys, dogs, cats, rats, cavies, guinea pigs and mice.
Types of surgery successfully done in animals include: caesarean section, ovario-hysterectomy; gastric and intestinal surgery; nephrectomy; removal of mammary and skin tumours; surgery of the eye, ear, anal and vaginal region, limbs and teats; surgery on the lip, oesophagus, trachea, frontal sinuses; rumen; navel hernia repair; surgery on the bladder and urethra; orthopaedic surgery (bones, joints); removal of parotid and submaxillary glands; castration, orchidopexy, inguinal hernia. The late Dr. Westermayer's method for reposition of the prolapsed uterus has been mentioned already, as has AP therapy for the relief of dystocia. (See the paper on AP effects on the body's defence systems. See also the paper on the integration of AP into routine vet practice).
Experimental surgery under AA includes: pain responses to towel clips, incision, thermal and electrical stimuli; thoracotomy, laparotomy, limb and skin surgery.
2. EQUIPMENT AND METHODS OF RESTRAINT FOR AA
Equipment: Most AA is done using electrostimulation (ES) through needles in the correct points (Electro-AP analgesia = EAA). The choice of points will be discussed later. Many different types of electrostimulator are on the market. Some are made in China, others in Japan, USA, Canada, Europe and Australia etc.
The equipment should be strong, portable and battery-operated. It should have outputs for at least 8 electrodes. There is little standardization of equipment. Newer models for human use would be adequate for EAA in animals. It is safer to use models which deliver a bipolar waveform, (+) and (-), at each electrode. This prevents the development of serious electrolytic lesions which could arise if a monopolar waveform was used for long periods, as in prolonged surgery.
The Model 71-3 General Purpose Electro-AP Apparatus is suitable for AA as well as AP therapy. I had 8 teeth extracted and 8 teeth filled under EAA with the Model 71-3. I used mainly ChiaChe (ST06) plus Earlobe "Dental Analgesia Point" on the affected side. Needles were inserted 12-20 mm in the points. Voltage was increased slowly to maximum tolerance (anaesthesia mode, dense-disperse waveform). Occasionally adjustable waveform at 5-10 Hz was used. After 30 minutes of induction, the output was usually at a setting of 4-5 on a 10 point scale. When heavy needle-probing of the gum caused no pain, dentistry could begin. Dental fillings under EAA were uneventful except in deep root fillings. If "nerve pain" arose, turning up the voltage usually controlled it. Extraction was painless or caused minimal pain in 5/8 cases but 3/8 extractions caused moderate to severe pain but were completed without the use of drug analgesia. An impacted wisdom-tooth required 10 minutes of very strong rocking to remove it from its socket. There was rather severe pressure-pain with that attempt but I was able to tolerate it without asking for another anaesthetic. My dentist told me that most patients could not have had the tooth removed unless they had general anaesthesia.
In human patients, Caesarean section has been done in Japan using electro-static or electromagnetic fields around the hands and feet. The apparatus used does not appear to have been tested in Europe or America. Childbirth has been helped in 60-80% of women treated by transcutaneous ES analgesia (TESA) of the thoraco-lumbo-sacral region. The apparatus used was the Travisens, available from Dan Sjo Elektronik AB, Box 144-17224, Sundbyberg, Sweden. TESA does not appear to have been tested in animals.
Restraint for AA in animals: Surgery under AA requires adequate restraint because consciousness and all sensations and reflexes (except those of pain) are retained.
In large animals, operations under AA may be performed with the animal in the standing position or in dorsal, lateral or ventral recumbency, depending on the type of operation and whether or not the animal is quiet. Horses and nervous cattle should be knocked by ropes or a short-acting knock-down anaesthetic. Nervous animals may be given a tranquilliser i/v. Recumbent animals should be roped securely and an attendant should ensure that the head is kept down. A blindfold over the animal's eyes helps to avoid fright by visual stimuli. Unnecessary noise, movement and fuss should be kept to a minimum.
The standing position may be used for surgery in quiet cattle. An attendant may hold the nose and the animal should be restrained in a suitable cattle crate, or ropes may be used through rings in the wall to keep the animal in one position. Kicking may be prevented by the usual methods as applied in operations under local anaesthesia.
Small animals are normally operated on in lateral, dorsal or ventral recumbency. If a special operation-harness is not available they are restrained by tying bandages from the hocks and elbows to suitable anchor-points on the operating table. Dogs are excellent subjects for AA but it is advisable to tie a tape bandage around the jaws to prevent biting. It helps if the owner or an attendant talks to the dog and comforts the animal from time to time during surgery. Cats are difficult animals to handle and some vets who have tried AA in cats have ceased to use the technique in this species.
3. AA TECHNIQUES IN LARGE AND SMALL ANIMALS
Electro-AP analgesia (EAA) is the most common method used. When the animal is properly restrained, AP needles are placed to the correct depth in the AA points related to the operation site. The stimulator is checked to ensure that the power switch is off. The output leads are then connected to the needles. Do not connect the leads from one output across the thoracic or posterior cervical region. This is especially advisable if the instrument uses (+) and (-) electrodes. In this case the correct connection would be as in the diagram on the next page. An output circuit placed across the thorax may interfere with cardiac function and may, on rare occasions, cause cardiac arrest.
Tape or suture the needles firmly in position. Otherwise, they are liable to become dislodged by muscle twitches induced by the stimulation, or by struggling in nervous animals. When the needles are in position, the output controls are checked to ensure they are set at zero. Attach the leads and turn on the power switch. Turn up the output controls slowly until the needles begin to twitch in time with the frequency of the stimulator. Increase the output voltage from each control to the maximum tolerance of the patient. At that point, the animal indicates a degree of discomfort or pain (restlessness, defensive reaction, struggling, vocalisation etc). Reduce the output to a "strong but acceptable level" (that which can be tolerated without obvious discomfort). Excessive stimulation reduces the EAA effect and to weak a stimulus may induce little or no analgesia.
Note: A needle can not twitch unless it is embedded in reactive muscle. As long as one of a pair is twitching, the paired needle is also receiving a similar stimulus. Needles may not twitch in points such as GV26. If output voltage is too high at such points, the animal will indicate discomfort. In that case, reduce the output to the tolerance of the patient.
Every 5 minutes or so, after switch-on, the operation site is tested for analgesia using rat-tooth forceps, towel clip, clamp or pin prick. Initially, full sensitivity to pain is present, as indicated by local muscle twitch or guarding, vocalisation or defence reactions/struggling. After 5-10 minutes, the response to pain stimulus decreases. After 20-40 minutes, in successful cases, the animal makes no response to strong pain stimuli in and around the operation site. The operation may then commence.
Pain stimuli may exceed the hypoalgesia (thereby inducing pain response by the animal) at certain stages of the operation, especially during incision and suturing of the skin, serosa (peritoneum, pleura etc) and incision of periosteum and nerves. During these stages of the operation the frequency or output voltage should be increased. This is normally sufficient to counteract the pain. Occasionally (in those animals which respond poorly to AA) it may be necessary to use small volumes of local anaesthetic injection or spray at these stages.
In the first few minutes after stimulation begins it is usual for the animal to show a mild stress reaction (dilated pupils, increased blood pressure, faster respiration and heart rate). These quickly return to normal or near normal levels, and should remain at this level during the operation. Studies of EEG patterns in animals under AA indicate that brain waves are in the alpha range (8-13 cycle per second) i.e., similar to those of drowsiness or light sleep. However, the animals are still conscious and can eat or drink and (in dogs) wag the tail if petted by someone they know. Because sight and hearing are unaffected (pupil reflex is also intact), unnecessary noise should be avoided and a blindfold may be desirable. Pupillary dilation and salivation occurs in some animals. If salivation is excessive or retching/vomiting occurs, this usually indicates that excessive traction on mesentery/internal organs is the cause. This may be partly counteracted by increase in frequency or output of the AA stimuli.
The choice of points for AA depends on the species of animal, the operation site and personal preference/experience. Many different combinations are effective and there is no one combination which is agreed by all authors. In general, points are chosen according to Channel theory of human AP.
Classic AP teaches that the Channels have a superficial course (Jing, from the first to the last point on the Channel), a deep course (going to the organ of the Channel and possibly linking to other organs and deep regions), a collateral course (Luo, which links up with its Mate Channel) and other connections linking to every part of the body, interior and exterior. For instance, the LV Channel (big toe to chest, under the nipple) also sends a branch to the eye. (Discussion of the deep, collateral and other connections is not included in this seminar. These concepts are covered in certain classic texts, such as those of Van Nghi and Mann).
Thus in eye operations, a LV point might be included; in tongue operations a HT point might be included; in ear and bone operations a KI point might be included. In man, AA sometimes uses Earpoints for the organ or region being incised, i.e. for lung operations, Earpoint LU; for appendectomy, Earpoint LI, or Appendix etc.
The general rule is to use Local Points (near the operation site). As will be seen from some point prescriptions below, this rule is not always obeyed. Other workers pay particular attention to the points or nerves supplying the operation site, or related to it. In human EAA, same workers add two needles, one on each side of the incision. The diagram shows 2 needles, 25 cm long, buried parallel to the incision:
......................... needle 1 (25 cm)
_ _ _ _ _ _ _ _ _ _ _ _ _ 25 cm incision
needle 2 (25 cm) .........................
Some workers prefer to use AP stimulation at a low frequency and to increase the frequency gradually during the induction period. For instance, Ishizaki recommended a frequency of 10 Hz, increasing to 30-50 Hz at the start of operation in dogs. Other operators prefer faster or slower frequencies. For instance, Matsumoto found that frequencies of less than 200 or greater than 10000 Hz were less satisfactory in rabbits than frequencies within this range.
Points used in AA in animals: Many different workers have used many different combinations of points in various animal species. Examples of point combinations are given later. The following table lists the points by authors whose work is discussed later. These points are similar in position to points of the same name and code in HUMAN AP.
Other points used in AA in animals are:
1. On the GV Channel:
BaiHui: In the dorsal midline of the lumbo-sacral space, depth 3-5 cm in horse/ox, to react the dura mater. There is no direct equivalent in human AP.
WeiGan: In the dorsal midline between coccygeal vertebrae 2-3. Depth 1-1.5 cm in horse/ox. There is no direct equivalent in human AP.
TianPing : In the dorsal midline, in the thoraco-lumbar space. Depth 2-4 cm in horse/ox, at 90 degrees to the surface). There is no direct equivalent in human AP.
SanTai: In the dorsal midline, between the spines of thoracic vertebrae 4-5 (some texts say T5-6). Depth 6-8 cm antero-ventrally in horse/ox. SanTai is equivalent to GV11 (Shen Tao).
2. HuaToChiaChi Points (X 35 in my coding system). These points are located on the paravertebral line from the first cervical to the last sacral vertebra, between the GV and inner line of the BL Channel. One pair of points is located beside each vertebra. X 35 points lying nearest to spinal nerves which supply the operation site may be added as secondary points.
3. ChihYi Points are on the course of the GV Channel but are not classic GV points. They have been described recently in relation to human AA. The main ones used in vet AA are over the dorsal spines of vertebrae: Dorsal 3,5,6,11 and Lumbar 1.
4. Para-incisional points are not often used in vet AA, as the needles may impede access to the site.
5. ChiehKou points. These are also described in recent human texts. They are local points at each end of the incision.
Points used in AA or EAA: The most commonly used points are UNDERLINED:Point Point name Point Point name Point Point name LU01 CHUNGFU SP03 TaiPai TH03 ChungChu LU02 YunMen SP04 KungSun TH05 WaiKuan LU03 TienFu SP06 SANYINCHIAO TH08 SANYANGLO LU05 ChihTse HT03 ShaoHai TH13 NaoHui LU06 KungTsui HT05 TungLi TH14 ChienLiao LU10 YuChi BL22 SanChiaoShu TH17 YiFeng LI04 HOKU BL23 SHENSHU TH23 SsuChuKuan LI10 SanLi BL40 YiHsi GB01 TungTzuLiao LI11 ChuChih BL49 ChihPien GB30 HuanTiao LI14 PiNao BL54 WeiChung GB34 YangLingChuan LI15 ChienYu BL57 ChengShan GB36 WaiChiu LI17 TienTing BL59 FuYang GB38 YangFu LI18 FuTu BL60 KunLun GB39 HsuanChung ST06 ChiaChe KI03 TaiHsi GB40 ChiuHsu ST25 TienShu PC04 HsiMen GB43 HsiaHsi ST36 TSUSANLl PC04.5 YIEYEN LV14 ChiMen ST40 FengLung PC05 ChienShih GV03a BAIHUI ST44 NeiTing PC06 NEIKUAN GV26 JenChung
6. Points described by Japanese workers also include: InKoTen (between metacarpal bones 3 and 4 in small animals); BoKoKu (between metatarsal bones 3 and 4 in small animals); GeiKo (on the lateral margin of the naso-labial fold in mice and rats); unnamed point (in the second interdigital space in rabbits on the hindlimb (this may correspond with ST44 (NeiTing)). The Japanese points do not appear to have equivalents in Chinese human or vet texts.
EXAMPLES OF POINT SELECTION IN LARGE ANIMALS: Points used for AA in horses and cattle.
a. Horse: LU01 (ChungFu) with TH08 (SanYangLo penetrating to YieYen) was one of the first combinations used in large animals ln China (Niboyet). It was used especially in thoracic and abdominal surgery. A needle is inserted to a depth of 3-5 cm in LU01 (behind the shoulder in the second intercostal space). A second needle is inserted at TH08 (about 1 handsbreadth below the elbow, on the lateral side). It is driven medially and downwards behind the radius/ulna to reach YieYen (PC04.5), just under the skin above the "chestnut". The needles are inserted on the uppermost limb (horse in lateral recumbency).
b. Horse: In navel hernia operation, Humphries used 4 needles: Set 1: LU01 (positive) with TH08 penetrating to PC04.5 (negative). Set 2: SP06 (positive) with ST36 (negative). The frequency was 200 Hz, square wave, altered to spike wave during surgery. This horse was very ill and was a high anaesthetic risk, yet the operation went perfectly and no signs of pain were detected at any stage in the operation, which lasted 4 hours.
c. Horse or ox: Sun et al used traditional Chinese vet AP points on hundreds of large animals (horses and cattle).
Points for abdominal, vaginal and hindlimb operations were : BaiHui (main point) plus WeiGan (secondary point) plus TianPing (minor point). In chest operations, they used SanTai. To each of these points they added points on or near the spinal nerves supplying the operation site + points from the attached charts nearest the incision site.
d. Cattle: Kothbauer did many Caesarian sections in cows using EAA. In his first 2 cases he used LV14 (8th intercostal space, at a level with the shoulder joint) with BL30, both points on the left side. EAA was given at 40 Hz, output causing marked muscle twitch. Induction time was 20 minutes.
e. Ox, pig: In Japan, the Akita Veterinary AP Research Unit tested many point combinations (including the classic LU01 with TH08 penetrating to PC04.5). They concluded that the best effective points in cattle and pigs were Tenpei (TianPing) and Hyahai (BaiHui). These points are located in the midline at the thoraco-lumbar space and the lumbo-sacral space, as in combinations (c) above. The depth of needle insertion would be similar to that in combination (c) above (the Chinese combination), i.e. penetrating almost to the dura mater. They used 30 Hz. Voltage (output) was increased if the animals were recumbent.
EXAMPLES OF POINT SELECTION IN SMALL ANIMALS
Dog:
a. Kitazawa (Gifu Veterinary Faculty, Japan) did dozens of operations in which he compared the efficiency of various point combinations. The best combination for surgery in all areas was BL23 bilateral. Equally good was SP06 bilateral, but EAA of this point occasionally caused convulsions.
The next best combination was 8 needles, one in each point on each limb: LI11 plus InKoTen (Japanese point, between metacarpals 3 and 4) plus ST36 plus BoKoKu (Japanese point, between metatarsals 3 and 4); 4 points, bilateral = 8 needles.
He also examined other combinations but his preference was for 2 needles in BL23 (left and right). This point is paravertebral between the transverse processes of lumbar vertebrae 2-3.
b. The late Dr. Ishizaki (Japan) did over 50 major operations in dogs with 95% success. Unfortunately, he had no simple combination of points, as he chose points according to Channel Theory and also points near the operation site. However, in general, for operations on the head, neck, thorax and upper limb he used points PC06 and TH08 bilateral, with the needles penetrating completely through the limb (in one side, out the other) behind the radius and ulna. For operations on the abdomen and hindlimbs, he used SP06 (penetrating completely through the limb) and ST36. For anal surgery he added points lateral to the anus.
c. In a large series of toxic pyometra cases, Arambarri and Cazieux in the Toulouse Vet School used AA at points SP06; ST36,25; plus para-incisional needles for ovariohysterectomy. Not one case died and all recovered uneventfully. EAA was given at 2.5 Hz, rising to 3.5-4.5 Hz during operation. Manual AA was also successful.
d. Ralston reported uneventful removal of bladder calculi and Caesarean section in high-risk dogs using needles bilaterally in LI04 and ST36 (positive poles) and SP06, LI11 (negative poles).
e. O'Boyle and Vajda used SP06 and ST36 (bilateral) in 15 dogs. The operations (all of which were done successfully without other anaesthetics) included Caesarean section, removal of abscessed mammary tumour, splenectomy, gastric and intestinal surgery and ovariohysterectomy. They used 125 Hz, square wave, 2 seconds on/2 seconds off.
Monkeys:
Many combinations can be used in monkeys. The ones listed below are only a few of the combinations listed in texts on human EAA.
Vierck applied an electrical pain stimulus to the gastrocnemius area of monkeys. Bilateral electrostimulation of ST36 gave marked hypo-algesic effects. He used 200 Hz monophasic square wave, 0.5 msec. Monkeys respond similarly to man in many aspects of AP. Thus one should expect the following points to be effective:
Dental surgery: LI04 plus ST06 or Ear Root (Dental) point plus ST06
Oral plus lip surgery: ST44 plus LI04 (Jacobs: 15 minutes at 100 Hz gave excellent results).
Thoracic surgery: TH08 penetrating to PC04.5 +/- PC06 (or) TH05 penetrating to PC06 (or) LI14; TH14 (or) LI04; PC06 (or) LI10; TH17
Abdominal surgery: SP06; ST36 (or) ChihYi points (main point in midline at vertebra T6 plus secondary point at T3. Upper abdominal surgery: add point at T5; lower abdomen: add point at T11).
Upper limb surgery: Choose points from LI04,11,15,17,18; LU02,5,10; TH03,4,13; PC04,6; HT03, depending on site of surgery, Channels near the operation site and the nerve supply.
Lower limb surgery: Choose points from SP03,4,6; GB30,34,36,38,39,40,43; LV02,03,05,06; KI03; ST36,40,44; BL40,49,54,57,59,60; ChihYi points (main point in midline over the 6th thoracic vertebra and secondary point over 1st lumbar vertebra; X 35 in region lumbar 1 to sacrum 2, depending on site of surgery, Channels near site and nerve supply.
Dorso-lumbar surgery: LI04; TH05 plus ChiehKou (local points at each end of the incision); ChihYi points.
Cats:
The cat is difficult to work with and resents needles placed in the feet. Lambardt used EAA at 2.5 Hz on 4 cats (3 ovariohysterectomies, 1 Caesarean section). His points were: ST36; BL49; LU01; TH08 (bilateral). The results were not satisfactory and he noted much struggling. Three assistants were needed to restrain the animals! He concluded that cats are not the best subjects for EAA.
Other workers have used cats very successfully in experimental work on EAA (confirmation that the limbic and cortical potentials elicited by pain stimuli were suppressed by EAA) and Still (1987) claimed very good surgical analgesia in cats, using EAA at pre- and post-auricular points, plus GV06b, BL23,23a,24, lumbo-sacral space (GV03a) and SP06. The choice of points and frequency of stimulation are important to good success, especially in cats.
Rabbits:
Matsumoto reported the best analgesia from ES of a single needle placed to a depth of 3 cm in the second interdigital space. The negative electrode was a needle placed in the thigh muscles or at the vertex of the head. This technique at 200-10000 Hz sine wave gave powerful analgesia of ventral aspects of the neck, upper limb, thorax, abdomen and thigh. The analgesic effect crossed the midline, i.e. a left needle gave left and right analgesia. Chinese workers have also used AA on Earpoints alone for abdominal surgery in rabbits.
Rats:
Toda et al have done many years of research with EAA in rats to study the mechanisms of EAA in the treatment of dental pain and as a preparation for dental surgery. They tested various points and concluded that the most effective points for dental analgesia were LI04 (bilateral) or needle cathode at GeiKo (Japanese points on the lateral margin of the naso-labial fold) and a 3 x 4 cm silver plate anode placed on the centre of the abdomen. The GeiKo point was stimulated at 45 Hz, 5 msec, until the nose twitched in frequency with the stimulator. Analgesia occurred on both sides of the mouth from stimulation of GeiKo on one side but was better on the side opposite to the needle.
In the experiments with LI04, they did extensive trials to examine various frequencies (0.5, 1,10,30,45,100,150,300,500,1000 Hz). They found that some analgesia occurred at all frequencies from 0.5 to 500 Hz but the best analgesia was given by frequencies between 30 and 150 Hz. 1000 Hz was unsatisfactory. Induction was about 15 minutes. They also tested stimulation patterns using pulse durations between 0.1-5.0 msec. The pulse duration had little effect on efficiency of analgesia.
Mice:
EAA at LI04, square wave, 4 Hz, 0.1 msec, for 20 minutes. Output level was adjusted until muscular contraction occurred and was increased to just below the level which caused the mice to vocalise (squeak). Under experimental conditions this had analgesic effects on the nose. The effects were reversed by opiate antagonists (levo-naloxone, naltrexone, cyclazine, diprenorphine) but not by dextro-naloxone (which has little opiate- antagonist effect) (Cheng & Pomeranz 1980).
Dogs, cats, monkeys, cavies and rats:
Lynd in the San Antonio Medical School, Texas, experimented with a "standard surgical incision and suturing" applied to the upper lateral abdomen. A lateral incision through skin and muscle layers was used in all animals. He used only simple insertion of needles (no ES) in the following points GB01; TH23; HT05; BL23,22; KI06. All points were needled bilaterally and the needles were left in position. When the animal lost its reaction to pinprick etc, the incision was made and was then sutured. He reported excellent analgesia but gave no statistics.