Propofol onset

Propofol is very lipid soluble, has a large volume of distribution, and has a rapid onset of action. It has comparable efficacy to midazolam for refractory GCSE. It has been associated with metabolic acidosis, hemodynamic instability, and bradyarrhythmias that are refractory to treatment. 

Propofol (Diprivan) is rapidly acting, has a short recovery time, and possesses antiemetic properties. A rapid onset of anesthesia (50 seconds) is achieved, and if no other drug is administered, recovery will take place in 4 to 8 minutes. The recovery is attributed to redistribution of the drug and rapid metabolism to glucuronide and sulfate conjugates by the liver and extrahepatic tissues, such as intestine and kidney. 

Propofol Rapid onset and rapid recovery Used in induction and for maintenance can cause hypotension has useful antiemetic action... 

Recovery is sufficiently rapid with most intravenous drugs to permit their use for short ambulatory (outpatient) surgical procedures. In the case of propofol, recovery times are similar to those seen with sevoflurane and desflurane. Although most intravenous anesthetics lack antinociceptive (analgesic) properties, their potency is adequate for short superficial surgical procedures when combined with nitrous oxide or local anesthetics, or both. Adjunctive use of potent opioids (eg, fentanyl, sufentanil or remifentanil see Chapter 31) contributes to improved cardiovascular stability, enhanced sedation, and perioperative analgesia. However, opioid compounds also enhance the ventilatory depressant effects of the intravenous agents and increase postoperative emesis. Benzodiazepines (eg, midazolam, diazepam) have a slower onset and slower recovery than the barbiturates or propofol and are rarely used for induction of anesthesia. However, preanesthetic administration of benzodiazepines (eg, midazolam) can be used to provide anxiolysis, sedation, and amnesia when used as part of an inhalational, intravenous, or balanced anesthetic technique. 

Finally, newer intravenous anesthetics such as etomidate (Amidate) and propofol (Diprivan) are available. Etomidate is a hypnoticlike drug that causes a rapid onset of general anesthesia with a minimum of cardiopulmonary side effects. Flence, this drug may be useful in patients with compromised cardiovascular or respiratory function. Propofol is a short-acting hypnotic that is useful as a general anesthetic in some... 

Propofol (2,6-diisopropylphenol) is an extremely popular intravenous anesthetic. Its rate of onset of action is similar to that of the intravenous barbiturates recovery is more rapid and patients are able to ambulate sooner after propofol. Furthermore, patients subjectively "feel better" in the immediate postoperative period after propofol as compared with other intravenous anesthetics. Postoperative nausea and vomiting is less common because propofol has antiemetic actions. Propofol is used for both induction and maintenance of anesthesia however, cumulative effects can delay arousal following prolonged infusion. These favorable properties are responsible for the extensive use of propofol as a component of balanced anesthesia and for its great popularity as an anesthetic for use... 

The two principal parenteral anesthetic drugs used clinically are thiopental (an old prototype) and propofol (a relatively new drug). Thiopental is a derivative of barbituric acid, while propofol is a substituted propylphenol. Onset and duration of anesthetic effect for the two drugs are similar. However, recovery is more rapid following infusion with propofol (a desirable feature). The relatively rapid clearance of propofol explains its less severe hangover in patients compared to thiopental and may allow for a more accelerated discharge from the recovery room. 

Propofol [pro POF ol] is an IV sedative/hypnotic used in the induction or maintenance of anesthesia. Onset is smooth and occurs within about 40 seconds of administration. Supplemenation with narcotics for analgesia is required. While propofol facilitates depression in the CNS, high plasma levels can cause excitation. Propofol decreases blood pressure without depressing the myocardium. It also reduces intracranial pressure. 

Clinical use of muscle relaxants. Among the available neuromuscular blockers, succinylcholine displays the fastest onset of action. The patient can be intubated as early as 30-60 seconds after intravenous injection ( rapid sequence intubation ), which is important in emergency situations with an increased risk of aspiration (e.g., ileus, full stomach, head trauma). Postoperative muscle pain due to succinylcholine can be prevented by preinjection of a small dose of a nondepolarizing blocker ( precurarization ). In combination with propofol p. 218), rocuronium (p.184) creates intubation conditions comparable to those obtained with succinylcholine. 

Propofol has a remarkably simple structure resembling that of phenol disinfectants. Because the substance is water-insoluble, an injectable emulsion is prepared by means of soy oil, phosphatide, and glycerol. The effect has a rapid onset and decays quickly, being experienced by the patient as fairly pleasant. The intensity of the effect can be well controlled during prolonged administration. Possible adverse reactions include hypotension and respiratory depression, and a potentially fatal syndrome of bronchospasm, hypotension, and erythema. 

Gastrointestinal endoscopy is one of the most commonly performed invasive procedures in clinical practice (for example about 500 000 procedures per annum in Australasia). Propofol is a short-acting intravenous anesthetic with a rapid onset of action and a short half-life, making it eminently suitable for day procedures. However, the use of propofol by non-anesthetists has been controversial because of the perceived risks of its low therapeutic ratio. 

Propofol is a non-barbiturate, i.v. anesthetic that provides rapid-onset, short-duration anesthesia. It is widely used in human and small animal anesthesia. Propofol has not yet reached widespread use in equine anesthesia but a number of investigations into its clinical use have now been reported. 

Propofol is an alkylphenol compound that is highly lipid soluble but water insoluble. Its lipid solubility allows rapid penetration of the blood-brain barrier after i.v. administration, with rapid onset of CNS effects. This physicochemical property also means that rapid redistribution of propofol from the brain to other body tissues plays a significant role in the termination of the anesthetic effect. 

Intravenous anesthetics are also relatively lipid-soluble, which helps account for their rapid onset. This high degree of lipid solubility allows them to rapidly cross the blood-brain barrier and partition into the brain. Barbiturates such as thiopental and methohexitol and the nonbarbiturates etomidate and propofol are often used to induce anesthesia, but only propofol is commonly used today as a general anesthetic by continuous infusion, thus only propofol will be discussed. 

Propofol is extremely hpid soluble and has a large volume of distribution. It has a very rapid onset of action and an extremely short half-life (2 to 4 minutes), which promotes rapid awakening on drug discontinuation. Although extensive data are not available, it appears to be effective in GCSE. " Doses can be found in Table 55-4. It may cause respiratory and cerebral depression and bradycardia. Although metabolic acidosis has been reported, the occurrence of propofol-associated metabolic acidosis is controversial. Finally, a normal adult dose may provide over 1000 calories per day as lipid at a cost to the patient that may exceed 1000 per day. 

Propofol Rapid onset, very C ardiorespiratory Painful on injection... 

The site of action of propofol is probably the GABA receptor. Propofol has a fast onset of action and very fast recovery time. It is metabolized rapidly and has an antiemetic effect. 

Sodium pentothal (also called thiopental sodium) is commonly used as an intravenous anesthetic. The onset of anesthesia and the loss of consciousness occur within seconds of its administration. Care must be taken when administering sodium pentothal because the dose for effective anesthesia is 75% of the lethal dose. Because of its toxicity, it cannot he used as the sole anesthetic. It is generally used to induce anesthesia before an inhalation anesthetic is administered. Propofol is an anesthetic that has all the properties of the perfect anesthetic It can he used as the sole anesthetic by intravenous drip, it has a rapid and pleasant induction period and a wide margin of safety, and recovery from the drug is rapid and pleasant. 

Inal MT, Mentis D, Vatan I, Cakir U, Yildiz B. Late-onset pulmonary edema due to propofol. Acta Anaesthesiol Scand... 

A case of delayed onset and prolonged dystonic movements attributed to propofol is reported [89 ]. 

Na HS, Hwang JW, Park SH, Oh AY, Park HP, Jeon YT, et al. IJrug-adrriinistration sequence of target-controUed propofol and remifentanil influences the onset of rocuronium. A double-blind, randomized trial. Acta Anaesthesiol Scand 2012 56 558-64. 

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