🚨Hepato-portal blood flow and hepatic enzymatic activity decrease
🚨Plasma albumin level is reduced as you age, and for plasma protein-bound drugs this will lead to an increased proportion of unbound, active drug.
🚨Glomerular filtration rate falls by approximately 1% per year beyond the age of 30
🚨Opioid receptors decrease in number and increase in affinity ( The importance of this factor is less than the above mentioned ones, in case of opioid toxicity in elderly)
🚨IMPORTANT: lean body mass, body fat and total body water all fall. The volume of distribution of most drugs is therefore reduced. B͎u͎t͎ t͎h͎e͎ T͎O͎T͎A͎L͎ B͎O͎D͎Y͎ W͎A͎T͎E͎R͎ ( and muscle mass) d͎e͎c͎r͎e͎a͎s͎e͎s t͎o͎ a͎ g͎r͎e͎a͎t͎e͎r͎ e͎x͎t͎e͎n͎t͎ t͎h͎a͎n͎ t͎h͎e͎ T͎O͎T͎A͎L͎ B͎O͎D͎Y͎ F͎A͎T͎.
⚙So drugs that are water-soluble, are affected more
🚨Elderly patients may be particularly sensitive to remifentanil, as a large proportion of its metabolism is catalysed by muscle-based esterases.
#DrugToxicity , #geriatrics , #anesthesia , #pharmacology
