Midazolam – Apart as a premedication, midazolam can be used as an induction agent at the dose of 0.2 to 0.3 mg/kg. It has slow onset of action when used alone, but the onset can be improved when using together with an opioid. However, for those with hypotension, midazolam can further reduce the blood pressure and has cardiac depressive effects. Therefore, dose reduction is required for the elderly, and for those with heart and liver failure. Methohexital – This is a GABA agonist. It works by reducing the dissociation of GABA from its receptors. The dosage is 1.5 mg/kg. It is metabolised in liver. However, methohexital can cause respiratory depression, venodilatation, myocardial depression, and hypotension. Additionally, it can also cause reduced cerebral blood flow and histamine release. It can cause distal thrombosis and tissue necrosis if given into the arterial system. Paralytics
Paralytics are also known as neuromuscular-blocking drugs (NMB). NMB can reduce the complication rates of rapid sequence induction such as inadequate oxygenation of the blood, airway complications, and instability of the cardiovascular system. NMB can be divided into two types: depolarising and non-depolarising blockers. Depolarising blockers resembles the acetylcholine and activates the motor end-plate of the neuromuscular junction (NMJ). Meanwhile, non-depolarising blockers competitively blocks the NMJ without activating the motor end plate. Depolarising blockers
Succinylcholine – This drug has rapid onset of action and fast duration. Its dosages are between 1 and 2 mg/kg body weight with common dosage of 100 mg. The drug can only be kept under room temperature for 14 days.
Therefore, for longer shelf life, it has to be kept under temperatures from 3.3 °C (37.9 °F) to 8.7 °C (47.7 °F). When the intravenous access is not obtainable, the 3 to 4 mg/kg of intramuscular doses can be given (usual dose of 300 mg). However, duration of onset will be delayed to 3 to 4 minutes. Repetitive dosages of succinylcholine are discouraged to prevent vagal stimulation which leads to bradycardia. Non-depolarising blockers
Rocuronium – The dosage of rocuronium is between 0.6 and 1.2 mg/kg. Since rocuronium has longer duration of onset, caution should be taken for those who are difficult to bag-mask ventilate. Vecuronium – The dosage of this drug is between 0.08 and 0.1 mg/kg. Vecuronium is only used when there is a shortage of drugs such as succinylcholine and rocuronium. Reversal agents
Sugammadex – It is used as a reversal agent for rocuronium and vecuronium. It works by encapsulating the paralytic drug thus preventing it from acting on the binding sites. The dose of 16 mg/kg is used for immediate reversal after administration such as during RSI. Doses of 2 mg/kg and 4 mg/kg are used if the patient has twitches evident on a twitch monitor and terminates the rocuronium action within 3 minutes. The FDA initially did not approve Sugammadex due to concerns over potential allergic reactions, however it was subsequently approved on December 15, 2015 for use in the United States.