Since we introduced acupuncture anesthesia for intracardiac surgery with extracorporeal circulation in 1972, 230 operations had been performed up to August 1978. Throughout the course of the operation EEG, ECG, respiratory tracing, plethysmograph, myograph and galvanic skin response were continuously monitored with a polygraph in 30 random cases. Tidal volume and minute volume were measured before and after opening of the chest and at the end of the operation in 43 cases. The arterial pH, PCO[2] and other items of blood gas analysis were determined in 49 cases.
Method: In accordance with the principles of selection of points along the course of Channels 10 groups of acupuncture points had been selected consecutively, and among them there was no apparent difference in effect. At present the points commonly used consist of bilateral Neiguan, Lique and Yunmen. As soon as needling sensation is felt after insertion, the acupuncture needle is connected to an electric stimulator which provides a current of 3--4 Hz in frequency. The intensity of stimulation is gradually increased up to an extent not beyond endurance of the patient. The induction time lasts 20--30 minutes. Preoperative supplementary medications are required, such as phenobarbital 0.02gm/kg given orally 2 hours before operation and pethidine 1 mg/kg. administered intravenously 15 minutes before operation. In order to enhance the analgesic effect an additional dose of pethidine (0.5 mg/kg) or fentanyl and haloperidol may be necessary during operation. Local infiltration of 1:200,000 adrenaline saline solution to the incision line is made in order to reduce the chance of employing electric cautery for coagulation and 0.25% xylocaine solution 40 ml are used for local infiltration in case analgesic effect is not satisfactory. No endotracheal intubation is applied and instead, nasal or mask oxygen supply is given during operation. All patients should be trained to practice abdominal breathing routinely for 1--2 weeks before operation.
The Shanghai Type II or III heart lung machine with a rotating disc or bubbling oxygenator was used for all cases. The machine was primed mainly with normal saline or balanced solution. The perfusion rate was 60--80 ml/kg/min. Cardioplegia was induced by local hypothermia with ice slush or together with coronary infusion with cold cardioplegic solution through the ascending aorta. For the ordinary cases, body temperature was controlled at about 36ºC, but for those more complicated cases, it was lowered to 30ºC (nasal) by blood stream cooling.
Clinical data: In this series of cases, the age of the patients was between 10--48 years. Intracardiac lesions and corresponding operations are listed in Table 1. According to the national unified standard, the effect of acupuncture anesthesia was graded as excellent in 42 cases (18.3%), good in 117 cases (50.9%), fair in 52 cases (22.7%) and poor in 19 cases (8.2%), with a favorable effect rate of 69.2%. Perfusion time over 60 minutes was found in 72 cases, over 100 minutes in 15 cases, the longest one being 132 minutes. For all cases except 6 cases, the ascending aorta was occluded, occlusion time being 6--80 minutes. After occlusion the heart was not arrested in 27 cases. After release of the occluding clamp, the heart resumed beating spontaneously in 56 cases and was resuscitated by electrical defibrillator in 141 cases. There were 11 operative mortalities and the causes of deaths were not related to acupuncture anesthesia.
Results of EEG, ECG etc. EEG showed a predominance of à rhythm and in some cases during cardiopulmonary bypass, there was sporadic é or 235 rhthym which disappeared soon after termination of perfusion. In ECG several individual cases demonstrated atrial or ventricular extrasystoles before bypass, but 1/3 of the cases had supraventricular tachycardia after termination of the bypass. Phlethysmographic waves disappeared during perfusion. Galvanic skin response appeared at any maneuver on the patient's body surface such as skin disinfection, skin incision etc, but subsided or even disappeared after the chest was opened. EMG response was present throughout the course of the operation, and there were more frequent occurence during incising the skin, splitting of the sternum and suturing of the skin. In the majority of patients the respiratory wave disappeared during perfusion but spontaneous respiration recovered 1--2 minutes after termination of perfusion. Respiratory spirometry did not demonstrate marked changes before, after opening of the chest and at the end of operation. There was no parallel correlation between the effect grading of acupuncture anesthesia and the variance in plethysmograph, galvanic skin response, respiratory tracings or heart rates.
Under acupuncture anesthesia, the patients' conciousness and normality of EEG activities are closely related with the mean arterial pressure observed during perfusion, the volume of perfusion and oxygenation of the perfusing blood. For these purposes, the following conditions are required: 1. arterial pressure not below 50mmHg; 2. perfussion rate about 60--80 ml/kg/min; 3. blood oxygen partial pressure above 100 mmHg and oxygen saturation above 95%. Furthermore, consciousness is also influenced by body temperature, drugs administered and operative maneuvers such as lifting up of the heat. During perfusion, close observation of the mental state of the patient and continuous monitoring of EEG may detect the presence of cerebral anoxia. It may also serve as a guide to judge whether the performing extracorporeal circulation is physiological or not.
During cardiac operations, especially direct vision intracardiac operations, the occurence of cardiac arrhthymia is not infrequent. An analysis of ECG recorded continuously during the operations showed that not a single case of serious arrhythmia ever occurred before perfusion. It is probably due to the fact there is less cardiac depression effect from anesthetic drugs under acupuncture anesthesia than under conventional general anesthesia. Acupuncture anesthesia may also avoid ill effects and reactions induced by endotracheal intubation and hypothermia. Fluctuation of arterial blood pressure is also less in acupuncture anesthesia patients. In comparison of 60 cases under general anesthesia with 155 concomittent cases under acupuncture anesthesia, lowering of blood pressure was present in 19 cases (31.7%) in the general anesthesia group before perfusion and 34 cases (56.7%) after perfusion, requiring the administration of vasopressors, while in the acupuncture group only 11 cases (7.1%) before perfusion and 43 cases (27.7%) after perfusion respectively (P<0.01).
In this series the respiratory complications in the postoperative period were much less than those under general anesthesia. When 155 cases of intracardiac operations under acupuncture anesthesia were compared with 60 concomittent cases under general anesthesia, there were 5 cases with respiratory complications. Among these, 2 cases were intubated during operation and one case was intubated before operation under conscious state. With these exceptions, only 2 of the 152 non-intubation cases had respiratory complications. In the general anesthesia group 11 cases suffered from respiratory complications, including 9 cases of pulmonary infection, one case of atelactasis, and one case of pleuritis. However, for cyanotic cases with severe hypoxia and cardiac function more than grade II, general anesthesia with intubation is more suitable because it insures respiratory tract patency and provides sufficient supply of oxygen.
Measurement of pH, PaCO[2] and other parameters of blood gas analysis in 49 cases showed some metabolic acidosis before and during perfusion, which disappeared 3 hours afterwards. These findings correspond to those in conventional general anesthesia.
Besides these above mentioned measures, several items should be emphysized in order to increase the effect of acupuncture anesthesia. They are: 1. Guidelines for the selection of patient such as age over 14 years old, willingness to be cooperative, diagnosis definite and cardiac lesions not very complicated should be followed. 2. Operative manipulation must be gentle and speedy, the splitted sternal parts should be spreaded gradually. Electric cauterization should be avoided if possible. 3. A team work among surgeons, anesthetists and perfusionists is mandatory.
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