1. Goal of Therapy
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Use the lowest effective dose of paralytic.
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Minimizes recovery time once infusion is stopped.
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Requires objective monitoring of degree of paralysis.
2. Monitoring: Train-of-Four (TOF)
Method: Peripheral nerve stimulation → 4 quick electrical impulses (~0.5 sec apart).
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Sites used:
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Ulnar nerve → thumb adduction, finger flexion.
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Facial nerve → eyelid closure, furrowed brow.
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Posterior tibial nerve → great toe flexion.
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Response = # of twitches out of 4:
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1/4 → ~90% receptor blockade.
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2/4 → ~80% blockade.
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3/4 → ~75% blockade.
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4/4 → minimal blockade.
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Typical goal: 2–3 twitches (depends on indication).
Common mistake: forgetting baseline TOF before starting infusion.
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Needed to confirm electrode placement + correct voltage.
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Edema or prolonged therapy may require ↑ output over time.
3. Recovery Assessment
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Large muscles recover first, small muscles later.
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Signs of recovery:
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Sustained head/leg lift.
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Eye opening.
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Strong hand squeeze.
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Tongue protrusion.
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Purposeful movement.
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Strong cough, bite, swallow.
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Prolonged infusion → risk of weakness, myopathy, disuse atrophy.
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Risk ↑ with concurrent steroids.
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4. Sedation Considerations
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Paralytics provide no analgesia, amnesia, or sedation.
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Patients must always be deeply sedated.
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Tools:
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BIS monitor (if available).
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Otherwise → high-dose sedation, err on side of caution.
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Danger: patient may appear calm but be awake → terrifying experience.
5. Supportive Care
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Eye care: lubricating ointment/prophylaxis → prevent corneal abrasions.
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Pupil checks: still valid; paralytics do not affect pupillary or cardiac muscle.
6. Key Points to Remember
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Always titrate paralytics to effect (goal 2–3 TOF twitches).
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Document baseline TOF before infusion.
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Assess recovery with small muscle strength tests.
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Prevent complications: sedation, eye care, monitor for weakness/myopathy.
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Pupils and cardiac muscle remain unaffected.
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