Succinylcholine - Imp Points.

Synonym : Suxamethonium.

Depolarizing skeletal muscle relaxant.

Initially produces twitching and fasiculations, followed by Flaccid paralysis.

Shortest and Fastest acting.

Only skeletal muscle relaxant causing stimulation of Autonomic ganglia and Vagus.

M/c used for ET intubation.

Partially hydrolysed by pseudocholinesterase. Deficiency of this enzyme causes Non depolarizing block (phase two/dual block.)

Non depolarizing block also seen with increased dose and duration of administration.
7-10mg/kg or 30-60 mins of exposure.

Post operative muscle pain (myalgia) is very common.

M/c cause of Malignant Hyperthermia also enhances the same caused due to Halothane.
Also causes Trismus in patients susceptible for Malignant Hyperthermia.

Causes increase in all pressures :
Intraocular, intracranial, intravenously,BP.

Prolonged apnea is seen in patients with deficiency of pseudocholinesterase or if the enzyme is atypical. Also can be seen in cases of electrolyte imbalances.
Management is to continue mechanical ventilation by intermittent positive pressure, maintain anesthesia and wait for spontaneous recovery.

Incase of no recovery use Fresh Frozen Plasma which will provide the pseudocholinesterase​ enzyme or use heat treated preparation of cholinesterase.

Contraindications:
Hyperkalemia
Head injury
Glaucoma
Cerebral stroke.
Prolonged intrabdominal infection
Tetanus
Guillan Barre syndrome.
Metabolic acidosis.
Muscular Dystrophy.
Burns.
Shock.