Causes and treatment of PONV Flashcards
PONV occurs in ?% of surgical patients, leading to delayed ? and recovery.
The pathophysiology involves input to the vomiting centre from·
- Higher ? centres: ?/fear.
- The ?/ small ?: direct surgical effects.
- The ? trigger zone: anaesthetic drugs and ?
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Risk factors;
Patient: more common in ?, obesity, non-?, previous history of ?.
Procedure: ?, ? or ENT.
Anaesthetic: ? duration of surgery, ?A, use of ? agents.
Post-operative: pain, ?analgesia, ?, hypo?
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PONV treatment pathway;
- ? ?mg/8h IV/IM/PO.
- ? ?mg/6h I?.
- ? ?mg/8h ?/IV.
? ?mg IV can be added at any stage if nausea is not controlled.
It is often added with ?.
cyclizine 50 prochlorperazine 12.5 m ondansetron 4 PO dexamethasone 8 cyclizine
Cyclizine;
Anti-? useful in middle ?surgery and ? sickness.
Contra-indicated in ? failure, B??, ?/renal disease.
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Metoclopramide / Prochlorperazine / ?;
? antagonists that stabilise the CTZ and have ? effects.
? relatively ineffective in PONV.
Prochlorperazine contraindicated in ?.
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Ondansetron;
? effective drug.
? antagonist effective in the ? of PONV by blocking ? afferents from the gut / CTZ.
Can be given prophylactically.
Caution in ? impairment, ?prolongation, pregnancy/ ? ?.
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Dexamethasone;
? with unknown MOA acting to augment the effects of other drugs.
Should be used ? on in the treatment pathway.
glucocorticoid
early
The notion is that prevention is better than cure, so in high risk patients, use of
? and ? anaesthetics/ ??? is kept to a minimum, with ?anaesthesia used if possible.
opioids
inhaled
NO2
regional
