Methohexital
Thiopental
Anesthesia, Intravenous
Analog-Digital Conversion
Propanidid
Etomidate
Anesthetics, Intravenous
Alfaxalone Alfadolone Mixture
Biopharmaceutics
Anesthesia Recovery Period
Amobarbital
Preanesthetic Medication
Thiamylal
Comparison of recovery of propofol and methohexital sedation using an infusion pump. (1/103)
Two sedative anesthetic agents administered by an infusion pump were compared during third molar surgery. Forty American Society of Anesthesiologists (ASA) class I or II volunteers were randomly allocated to two groups. All subjects received supplemental oxygen via a nasal hood, fentanyl (0.0007 mg/kg intravenous [i.v.] bolus), and midazolam (1 mg/2 min) titrated to effect. Patients then received either 0.3 mg/kg of methohexital or 0.5 mg/kg of propofol via an infusion pump. Upon completion of the bolus, a continuous infusion of 0.05 mg/kg/min methohexital or 0.066 mg/kg/min propofol was administered throughout the procedure. Hemo-dynamic and respiratory parameters and psychomotor performance were compared for the two groups and no significant differences were found. The continuous infusion method maintained a steady level of sedation. Patients receiving propofol had a smoother sedation as judged by the surgeon and anesthetist. (+info)Drug blockade of open end-plate channels. (2/103)
1. The actions of amylobarbitone, thiopentone, methohexitone and methyprylone at voltage-clamped frog end-plates were studied. 2. In the presence of barbiturates the conductance change evoked by an iontophoretic carbachol application was reduced by a prepulse of carbachol. The extra inhibition evoked by a prepulse disappeared exponentially with a time constant of 150-200 ms. 3. Barbiturates produce an increased rate of decay of nerve evoked endplate currents. Tne concentration and voltage dependence of the barbtiruate e.p.c. decay rates tally with the hypothesis that the increased rate of decay is due to block of active receptor-channel complexes by barbiturates with a rate constant of 10(6) M-1S-1. 4. Conductance changes produced by bath applied agonists were depressed by thiopentone, the effect becoming greater the higher the agonist concentration. This effect, and also the observation that the concentration of thiopentone required to depress the bath agonist response is much greater than the apparent dissociation constant for binding to active receptor-channel complexes calculated from kinetic measurements, suggest that the selectivity for binding to open receptor-channel complexes is very high. 5. Methyprylone, which is structurally similar to the barbiturates, is only a weak antagonist and shows no interpulse interaction. It was predicted that methyprylone should produce fast and slow components in the e.p.c. decay, and this prediction was verified. 6. In the presence of barbiturates large iontophoretic carbachol applications produce conductance changes which show fast and slow components. Under these conditions the effects of carbachol prepulses become complex. However the effects are qualitatively consistent with the notion that different components of the response are contributed by channels located at various distances from the iontophoretic pipette tip. 7. All the data agree with a model in which the channel has three stages: closed, open and blocked. Only open channels can block, and blocked channels can only open. (+info)Effects of i.v. anaesthetic agents on the chemotaxis of eosinophils in vitro. (3/103)
Polymorphonuclear eosinophilic leucocytes (PME) participate in wound healing processes, the inflammatory response, bronchial asthma, allergies and defence against invading parasites. We have examined the effects of thiopental, methohexital, propofol, etomidate and ketamine on PME chemotaxis in vitro. PME were isolated from venous blood samples of 10 healthy volunteers using multi-stage Percoll gradient centrifugation. Eosinophilic chemotaxis was determined using a 48-well microchemotaxis chamber. Thiopental 150 micrograms ml-1 and etomidate 0.32 microgram ml-1 caused significant (P < or = 0.05) inhibition of PME chemotaxis. We conclude that thiopental and etomidate may have an adverse influence on wound healing processes and parasitic diseases. Further studies are recommended. (+info)Isoflurane alters the recirculatory pharmacokinetics of physiologic markers. (4/103)
BACKGROUND: Earlier studies have demonstrated that physiologic marker blood concentrations in the first minutes after administration, when intravenous anesthetics exert their maximum effect, are determined by both cardiac output and its distribution. Given the reported vasodilating properties of isoflurane, we studied the effects of isoflurane anesthesia on marker disposition as another paradigm of altered cardiac output and regional blood flow distribution. METHODS: The dispositions of markers of intravascular space and blood flow (indocyanine green), extracellular space and free water diffusion (inulin), and total body water and tissue perfusion (antipyrine) were determined in four purpose-bred coonhounds. The dogs were studied while awake and while anesthetized with 1.7%, 2.6%, and 3.5% isoflurane (1.15, 1.7, and 2.3 minimum alveolar concentration, respectively) in a randomized order determined by a Latin square experimental design. Marker dispositions were described by recirculatory pharmacokinetic models based on very frequent early, and less frequent later, arterial blood samples. These models characterize the role of cardiac output and regional blood flow distribution on drug disposition. RESULTS: Isoflurane caused a significant and dose-dependent decrease in cardiac output. Antipyrine disposition was profoundly affected by isoflurane anesthesia, during which nondistributive blood flow was maintained despite decreases in cardiac output, and the balance between fast and slow tissue volumes and blood flows was altered. CONCLUSIONS: The isoflurane-induced changes in marker disposition were different than those the authors reported previously for halothane anesthesia, volume loading, or hypovolemia. These data provide further evidence that not only cardiac output but also its peripheral distribution affect early drug concentration history after rapid intravenous administration. (+info)Cardiovascular effects of endothelin-1 and endothelin antagonists in conscious, hypertensive ((mRen-2)27) rats. (5/103)
SB 209670 is a potent antagonist of the vasoconstrictor (ET(A)- and ET(B)-receptor-mediated) and vasodilator (ET(B)-receptor-mediated) effects of endothelin, whereas SB 234551 is relatively selective for the constrictor (ET(A)-receptor-mediated) effects. Since we had previously found SB 209670 exerted antihypertensive, vasodilator effects in conscious, heterozygous, transgenic ((mRen-2)27) (abbreviated to TG) rats, here we compared the two antagonists in that model, and assessed their chronic effects on responses to exogenous endothelin-1. We did this to test our global hypothesis, namely, that SB 209670, but not SB 234551, would cause inhibition of the depressor effects of exogenous endothelin-1 in vivo, and that this differential effect would be associated with a more marked antihypertensive action of SB 234551 in TG rats. SB 209670 and SB 234551 (infused for 50 h) exerted similar, sustained, antihypertensive effects in TG rats. The antihypertensive effects of the antagonists occurred at times when the pressor effects of exogenous endothelin-1 were not significantly inhibited. Furthermore, SB 234551 did not exert a greater antihypertensive effect than SB 209670 at a time (i.e., 2 - 4 h) when the depressor effects of endothelin-1 were abolished by the latter, but not by the former (although this differential action was lost after 24 h infusion). The results caused us to reject the hypothesis that selective antagonism of the vasoconstrictor effects of endothelin-1 would result in SB 234551 exerting a greater antihypertensive effect than SB 209670 in TG rats. (+info)Left ventricular dynamics of trained dogs anesthetized with methohexital. (6/103)
The cardiac response to intravenous administration of the ultrashort-acting oxybarbiturate anesthetic, methohexital sodium, was studied in trained dogs. Heart rate increased immediately and gradually declined to the control value 60 minutes later. Stroke volume decreased immediately, reversed transiently, and decreased again, to return gradually to the control value at one hour. Peak aortic flow velocity and peak aortic flow acceleration paralleled the triphasic response of stroke volume. Cardiac output decreased initially, then increased to above the control value to a maximum at the time of maximum heart rate, then decreased again to below the control value by 30 minutes. From 30 minutes to 60 minutes cardiac output gradually returned to the control value. (+info)Total intravenous anaesthesia with methohexitone or propofol for knee arthroscopy in day-case surgery. (7/103)
The aim of the study was to assess the usefulness of methohexitone and propofol in total intravenous anaesthesia applied during planned knee joint arthroscopy in day-case surgery. Studies comprised 186 patients divided into 2 groups depending on the anaesthetic used (methohexitone n = 112 or propofol n = 74). ECG, heart rate, systolic and diastolic blood pressure and blood saturation using pulsoxymetry were monitored during anaesthesia. The time of regaining consciousness was measured and the orientation test was performed 5 and 10 minutes after regaining consciousness. Our results and observations confirm that total intravenous anaesthesia is useful in day-case surgery for knee joint arthroscopy. Both methohexitone and propofol cause cardiac and respiratory depression. Patients on propofol regain psychomotoric efficiency earlier then patients who received methohexitone. (+info)Intravenous therapy and EEG monitoring in prolonged seizures. (8/103)
Attempts were made to control prolonged seizures with rapid intravenous administration of either diazepam or methohexitone in relatively small doses under electroencephalographic (EEG) monitoring. The clinical and EEG features are discussed in relation to 65 episodes which occurred in 51 infants and children. Both clinical and EEG effects may become apparent in half a minute when the drug is administered with this technique and no undesirable side-effects were observed. The return of consciousness was not impaired by the small amounts of these drugs and the cumulative effects were negligible, allowing repeated injections if necessary. This technique avoids the disadvantages of larger doses of drugs given by slow intravenous infusion. (+info)Methohexital is a rapidly acting barbiturate sedative-hypnotic agent primarily used for the induction of anesthesia. It is a short-acting drug, with an onset of action of approximately one minute and a duration of action of about 5 to 10 minutes. Methohexital is highly lipid soluble, which allows it to rapidly cross the blood-brain barrier and produce a rapid and profound sedative effect.
Methohexital is administered intravenously and works by depressing the central nervous system (CNS), producing a range of effects from mild sedation to general anesthesia. At lower doses, it can cause drowsiness, confusion, and amnesia, while at higher doses, it can lead to unconsciousness and suppression of respiratory function.
Methohexital is also used for diagnostic procedures that require sedation, such as electroconvulsive therapy (ECT) and cerebral angiography. It is not commonly used outside of hospital or clinical settings due to its potential for serious adverse effects, including respiratory depression, cardiovascular instability, and anaphylaxis.
It's important to note that Methohexital should only be administered by trained medical professionals under close supervision, as it requires careful titration to achieve the desired level of sedation while minimizing the risk of adverse effects.
Thiopental, also known as Thiopentone, is a rapid-onset, ultrashort-acting barbiturate derivative. It is primarily used for the induction of anesthesia due to its ability to cause unconsciousness quickly and its short duration of action. Thiopental can also be used for sedation in critically ill patients, though this use has become less common due to the development of safer alternatives.
The drug works by enhancing the inhibitory effects of gamma-aminobutyric acid (GABA), a neurotransmitter in the brain that produces a calming effect. This results in the depression of the central nervous system, leading to sedation, hypnosis, and ultimately, anesthesia.
It is worth noting that Thiopental has been largely replaced by newer drugs in many clinical settings due to its potential for serious adverse effects, such as cardiovascular and respiratory depression, as well as the risk of anaphylaxis. Additionally, it has been used in controversial procedures like capital punishment in some jurisdictions.
Intravenous anesthesia, also known as IV anesthesia, is a type of anesthesia that involves the administration of one or more drugs into a patient's vein to achieve a state of unconsciousness and analgesia (pain relief) during medical procedures. The drugs used in intravenous anesthesia can include sedatives, hypnotics, analgesics, and muscle relaxants, which are carefully selected and dosed based on the patient's medical history, physical status, and the type and duration of the procedure.
The administration of IV anesthesia is typically performed by a trained anesthesiologist or nurse anesthetist, who monitors the patient's vital signs and adjusts the dosage of the drugs as needed to ensure the patient's safety and comfort throughout the procedure. The onset of action for IV anesthesia is relatively rapid, usually within minutes, and the depth and duration of anesthesia can be easily titrated to meet the needs of the individual patient.
Compared to general anesthesia, which involves the administration of inhaled gases or vapors to achieve a state of unconsciousness, intravenous anesthesia is associated with fewer adverse effects on respiratory and cardiovascular function, and may be preferred for certain types of procedures or patients. However, like all forms of anesthesia, IV anesthesia carries risks and potential complications, including allergic reactions, infection, bleeding, and respiratory depression, and requires careful monitoring and management by trained medical professionals.
Analog-digital conversion, also known as analog-to-digital conversion (ADC) or digitization, is the process of converting a continuous physical quantity or analog signal into a discrete numerical representation or digital signal. This process typically involves sampling the analog signal at regular intervals and then quantizing each sample by assigning it to a specific numerical value within a range. The resulting digital signal can be processed, stored, and transmitted more easily than an analog signal. In medical settings, this type of conversion is often used in devices such as electrocardiograms (ECGs) and blood pressure monitors to convert physiological signals into digital data that can be analyzed and interpreted by healthcare professionals.
Propofol, also known as Propanidid among other names, is a short-acting medication that belongs to a class of drugs called general anesthetics. It is used during induction and maintenance of general anesthesia, sedation for mechanically ventilated adults, and procedural sedation.
Propofol works by depressing the central nervous system and producing a state of decreased consciousness, amnesia, and muscle relaxation. It is administered intravenously and its effects begin to be felt within 30 seconds to 1 minute after injection, with an average duration of action of about 4-6 minutes.
Like all general anesthetics, propofol carries a risk of serious side effects, including respiratory depression, low blood pressure, and allergic reactions. It should only be administered by trained medical professionals in a controlled clinical setting.
Etomidate is a intravenous anesthetic medication used for the induction of general anesthesia. It provides a rapid and smooth induction with minimal cardiovascular effects, making it a popular choice in patients with hemodynamic instability. Etomidate also has antiseizure properties. However, its use is associated with adrenal suppression, which can lead to complications such as hypotension and impaired stress response. Therefore, its use is generally avoided in critically ill or septic patients.
The medical definition of 'Etomidate' is:
A carboxylated imidazole derivative that is used as an intravenous anesthetic for the induction of general anesthesia. It has a rapid onset of action and minimal cardiovascular effects, making it useful in patients with hemodynamic instability. Etomidate also has antiseizure properties. However, its use is associated with adrenal suppression, which can lead to complications such as hypotension and impaired stress response. Therefore, its use is generally avoided in critically ill or septic patients.
Intravenous anesthetics are a type of medication that is administered directly into a vein to cause a loss of consciousness and provide analgesia (pain relief) during medical procedures. They work by depressing the central nervous system, inhibiting nerve impulse transmission and ultimately preventing the patient from feeling pain or discomfort during surgery or other invasive procedures.
There are several different types of intravenous anesthetics, each with its own specific properties and uses. Some common examples include propofol, etomidate, ketamine, and barbiturates. These drugs may be used alone or in combination with other medications to provide a safe and effective level of anesthesia for the patient.
The choice of intravenous anesthetic depends on several factors, including the patient's medical history, the type and duration of the procedure, and the desired depth and duration of anesthesia. Anesthesiologists must carefully consider these factors when selecting an appropriate medication regimen for each individual patient.
While intravenous anesthetics are generally safe and effective, they can have side effects and risks, such as respiratory depression, hypotension, and allergic reactions. Anesthesia providers must closely monitor patients during and after the administration of these medications to ensure their safety and well-being.
The Alfaxalone Alfadolone Mixture is a veterinary anesthetic agent, which contains two active ingredients: alfaxalone and alfadolone. Both are neuroactive steroids that depress the central nervous system, leading to sedation, muscle relaxation, and eventually anesthesia.
The mixture is used for induction and maintenance of anesthesia in various animal species, including dogs, cats, and horses. It provides smooth induction and rapid recovery from anesthesia, making it a popular choice among veterinarians. However, as with any anesthetic agent, there are potential risks and side effects associated with its use, such as respiratory depression, cardiovascular depression, and apnea. Proper dosing, monitoring, and management are essential to ensure the safety and efficacy of this anesthetic agent in veterinary medicine.
Biopharmaceutics is a branch of pharmaceutical sciences that deals with the study of the properties of biological, biochemical, and physicochemical systems and their interactions with drug formulations and delivery systems. It encompasses the investigation of the absorption, distribution, metabolism, and excretion (ADME) of drugs in biological systems, as well as the factors that affect these processes.
The main goal of biopharmaceutics is to understand how the physical and chemical properties of a drug and its formulation influence its pharmacokinetics and pharmacodynamics, with the aim of optimizing drug delivery and improving therapeutic outcomes. Biopharmaceutical studies are essential for the development and optimization of new drugs, as well as for the improvement of existing drug products.
Some key areas of study in biopharmaceutics include:
1. Drug solubility and dissolution: The ability of a drug to dissolve in biological fluids is critical for its absorption and bioavailability. Biopharmaceutical studies investigate the factors that affect drug solubility, such as pH, ionic strength, and the presence of other molecules, and use this information to optimize drug formulations.
2. Drug permeability: The ability of a drug to cross biological membranes is another key factor in its absorption and bioavailability. Biopharmaceutical studies investigate the mechanisms of drug transport across cell membranes, including passive diffusion, active transport, and endocytosis, and use this information to design drugs and formulations that can effectively penetrate target tissues.
3. Drug metabolism: The metabolic fate of a drug in the body is an important consideration for its safety and efficacy. Biopharmaceutical studies investigate the enzymes and pathways involved in drug metabolism, as well as the factors that affect these processes, such as genetic polymorphisms, age, sex, and disease state.
4. Drug interactions: The interaction between drugs and biological systems can lead to unexpected effects, both beneficial and harmful. Biopharmaceutical studies investigate the mechanisms of drug-drug and drug-biological interactions, and use this information to design drugs and formulations that minimize these risks.
5. Pharmacokinetics and pharmacodynamics: The study of how a drug is absorbed, distributed, metabolized, and excreted (pharmacokinetics) and how it interacts with its target receptors or enzymes to produce its effects (pharmacodynamics) is an essential component of biopharmaceutical research. Biopharmaceutical studies use a variety of techniques, including in vitro assays, animal models, and clinical trials, to characterize the pharmacokinetics and pharmacodynamics of drugs and formulations.
Overall, biopharmaceutical research is an interdisciplinary field that combines principles from chemistry, biology, physics, mathematics, and engineering to develop new drugs and therapies. By understanding the complex interactions between drugs and biological systems, biopharmaceutical researchers can design more effective and safer treatments for a wide range of diseases and conditions.
The anesthesia recovery period, also known as the post-anesthetic care unit (PACU) or recovery room stay, is the time immediately following anesthesia and surgery during which a patient's vital signs are closely monitored as they emerge from the effects of anesthesia.
During this period, the patient is typically observed for adequate ventilation, oxygenation, circulation, level of consciousness, pain control, and any potential complications. The length of stay in the recovery room can vary depending on the type of surgery, the anesthetic used, and the individual patient's needs.
The anesthesia recovery period is a critical time for ensuring patient safety and comfort as they transition from the surgical setting to full recovery. Nurses and other healthcare providers in the recovery room are specially trained to monitor and manage patients during this vulnerable period.
Amobarbital is a barbiturate drug that is primarily used as a sedative and sleep aid. It works by depressing the central nervous system, which can lead to relaxation, drowsiness, and reduced anxiety. Amobarbital is also sometimes used as an anticonvulsant to help control seizures.
Like other barbiturates, amobarbital has a high potential for abuse and addiction, and it can be dangerous or even fatal when taken in large doses or mixed with alcohol or other drugs. It is typically prescribed only for short-term use due to the risk of tolerance and dependence.
It's important to note that the use of barbiturates like amobarbital has declined in recent years due to the development of safer and more effective alternatives, such as benzodiazepines and non-benzodiazepine sleep aids.
Preanesthetic medication, also known as premedication, refers to the administration of medications before anesthesia to help prepare the patient for the upcoming procedure. These medications can serve various purposes, such as:
1. Anxiolysis: Reducing anxiety and promoting relaxation in patients before surgery.
2. Amnesia: Causing temporary memory loss to help patients forget the events leading up to the surgery.
3. Analgesia: Providing pain relief to minimize discomfort during and after the procedure.
4. Antisialagogue: Decreasing saliva production to reduce the risk of aspiration during intubation.
5. Bronchodilation: Relaxing bronchial smooth muscles, which can help improve respiratory function in patients with obstructive lung diseases.
6. Antiemetic: Preventing or reducing the likelihood of postoperative nausea and vomiting.
7. Sedation: Inducing a state of calmness and drowsiness to facilitate a smooth induction of anesthesia.
Common preanesthetic medications include benzodiazepines (e.g., midazolam), opioids (e.g., fentanyl), anticholinergics (e.g., glycopyrrolate), and H1-antihistamines (e.g., diphenhydramine). The choice of preanesthetic medication depends on the patient's medical history, comorbidities, and the type of anesthesia to be administered.
Dental anesthesia is a type of local or regional anesthesia that is specifically used in dental procedures to block the transmission of pain impulses from the teeth and surrounding tissues to the brain. The most common types of dental anesthesia include:
1. Local anesthesia: This involves the injection of a local anesthetic drug, such as lidocaine or prilocaine, into the gum tissue near the tooth that is being treated. This numbs the area and prevents the patient from feeling pain during the procedure.
2. Conscious sedation: This is a type of minimal sedation that is used to help patients relax during dental procedures. The patient remains conscious and can communicate with the dentist, but may not remember the details of the procedure. Common methods of conscious sedation include nitrous oxide (laughing gas) or oral sedatives.
3. Deep sedation or general anesthesia: This is rarely used in dental procedures, but may be necessary for patients who are extremely anxious or have special needs. It involves the administration of drugs that cause a state of unconsciousness and prevent the patient from feeling pain during the procedure.
Dental anesthesia is generally safe when administered by a qualified dentist or oral surgeon. However, as with any medical procedure, there are risks involved, including allergic reactions to the anesthetic drugs, nerve damage, and infection. Patients should discuss any concerns they have with their dentist before undergoing dental anesthesia.
Thiamylal is a fast-acting, ultra-short-acting barbiturate drug that is primarily used for the induction of anesthesia before surgical procedures. It works by depressing the central nervous system, producing sedation, relaxation, and hypnosis. Thiamylal has a rapid onset of action and its effects last only a short time, making it useful for quickly achieving a desired level of anesthesia while minimizing the risk of prolonged sedation or respiratory depression.
It is important to note that thiamylal should be administered under the close supervision of trained medical personnel, as its use carries certain risks and potential complications, such as cardiovascular and respiratory depression. Additionally, patients with a history of drug allergies, liver or kidney disease, or other medical conditions may require special precautions before receiving thiamylal.
Barbiturates are a class of drugs that act as central nervous system depressants, which means they slow down the activity of the brain and nerves. They were commonly used in the past to treat conditions such as anxiety, insomnia, and seizures, but their use has declined due to the risk of addiction, abuse, and serious side effects. Barbiturates can also be used for surgical anesthesia and as a treatment for barbiturate or pentobarbital overdose.
Barbiturates work by enhancing the activity of the neurotransmitter gamma-aminobutyric acid (GABA) in the brain, which results in sedation, hypnosis, and anticonvulsant effects. However, at higher doses, barbiturates can cause respiratory depression, coma, and even death.
Some examples of barbiturates include pentobarbital, phenobarbital, secobarbital, and amobarbital. These drugs are usually available in the form of tablets, capsules, or injectable solutions. It is important to note that barbiturates should only be used under the supervision of a healthcare professional, as they carry a high risk of dependence and abuse.