Techniques of Anesthesia-GA with Muscle Relaxant

GA with muscle relaxant
The basic principal is based on a triangle. One side represents perfect muscle relaxation, the second represents amnesia which is achieved with N2O or low concentration of any anaesthetic agent hyperventilation – Alkalosis depressing the awareness column of the Central Nervous System.
Ether 2% N2O or trichloroethylene 1 to 1.5% suffice (Halothane 0.5% muscle relaxant is administered as supplement where necessary Hyperventilation (alkalosis) potentiates both muscle relaxant action + amnesia. The muscle relaxant should be given as and when necessary and not at fixed timing depending on the pharmacological action. Do not use muscle relaxant for last 15 min. one should give small supplement of Thiopentone to achieve the goal. Reverse the muscle relaxant with atropine and prostigmine. It is mandatory. Even 0.25 or 0.5 mg of prostigmine makes an appreciable difference in patients who do not exhibit much relaxant effect.
Some points:
-Closed circuit, carbon dioxide absorber
-Never practice completely closed circuit
-The gas flow should not be less than 4 lit/min.
-Do not completely depend on the carbon-dioxide absorber
-Rising BP and tachycardia + lightness of anaesthesia should be taken as inefficient
-carbon dioxide absorption or elimination

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#21-25: Private Practice Anesthesia- Do’s and Dont’s

21. Beware of precipitous fall of BP in cases with induction of GA with regular dose of Thiopentone in failed spinal or epidural.
    
22. Patients with diabetes convert them on soluble insulin. If not possible give 10 units/ 500 dextrose. If the diabetes is mild and controlled on tablets give 10 units/ alt bottle of dextrose (5%); do not over treat. It is better to have a slightly hyperglycaemic patient rather than hypoglycaemic under anaesthesia. The only sign of caution you get is severe unexplainable tachycardia. Beware of armchair physicians who have not studied patients under anaesthesia or even entered the operation theatre.
    
23. Hypertensive patients who are controlled on drugs typically continue the drugs even before operation. If the BP is high, mainly due to fear in most cataract patients, administer 5-10 mg Nifedipine under the tongue on operation table before you start.
    
24. High risk patients, toxaemic, gasping with electrolyte imbalance: In this case, your first duty is to keep the patient alive. Avoid Thiopentone or if you do use it for your satisfaction administer homeopathic doses. Forget about Scoline twitchings and awareness of intubation. If Boyle’s Apparatus is available, do nitrous oxide, oxygen induction till eyelash reflex disappears. Give full dose (100 mg) of Scoline, do not compromise. Fractionate the muscle relaxant dose (long acting) or avoid if you can manage with repeated dilute Scoline. The dose needed may be unimaginably small.
    
25. Plan your method of anaesthesia well. Do not give spinal if the operation is not likely finish in time. Do not give Thiopentone only for surgeries causing immense pain. Use a combination of drugs with analgesic and amnesic drug.

#26-30: Private Practice Anesthesia- Do’s and Dont’s

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