Surgical procedures often require general anesthesia to induce either total loss of sensation or partial loss of sensation at a targeted site. The unconscious state, prevention of experiencing tactile sensations and pain helps individuals undergo complex surgical procedures. Without anesthesia, it is virtually impossible to perform procedures. The combination of intravenous drugs and gases, that put the individual in a state similar to sleep, is not free from possible undesirable effects. Following subsections offer an in-depth view, including possible side effects of anesthesia to help prepare for any outcomes.

Overview of anesthesia

On administering general anesthesia, the individual not only falls in a state similar to sleep, but the anesthetized brain also does not respond to pain stimuli. Typical reflexes that are witnessed when the body feels pain, is also not exhibited, as the brain is rendered fully unconscious.  A specialized area of practice, anesthesia is administered by a trained team comprising an experienced anesthesiologist and an anesthetist. During the process and the procedure, the team monitors the patient’s vital functions, and ensures that breathing is normal.

Procedures that involve considerable loss of blood, or those that are lengthy in duration, that may have an impact on breathing are all performed under general anesthesia. Similarly, procedures that may expose the patient to a cold environment are also undertaken with anesthesia. The choice of GA is also governed by the need for the patient to remain immobilized, and the combined effects of GA make it most suitable in such instances.

There are other types of anesthesia, that are chosen for procedures that do not require complete an unconscious state of mind. This usually involves application of local anesthesia on the affected part along with light sedation to ensure that the procedure is performed without pain. A slightly different form of this involves regional anesthesia and light sedation.

Types of regional anesthesia

Spinal anesthesia refers to injection of the anesthetic in the lower back, and this results in the lower half of the body turning numb to pain. This procedure is used during surgeries for the abdomen and the lower limb. Epidural anesthesia refers to the administration of anesthetic through a catheter, in place of the needle used in spinal anesthesia. This procedure is typically used during childbirth and for procedures that involve the lower limbs.

Mechanism of action of general anesthetics

While it may not be possible to pinpoint the exact mechanism of action that is responsible for outcomes in anesthesia, the effects are attributed to certain actions. For instance, the alteration of membrane proteins by facilitating the expansion of proteins is cited as a possible reason.  One of the reasons for the inability to pinpoint the mechanism of action is the properties of general anesthesia. For instance, various compounds act at the same time, and these effects while being somewhat similar in nature, are actually spread out to deliver the combined effect. This includes analgesic properties, amnesia effects and the act of immobilization of the patient. Drugs used in general anesthesia comprise a range, that extends from the basic alcohol chemical composition to complex compositions.

The combined effects of drugs used in general anesthesia act on the central nervous system in different manners. Though it is not possible to understand how each action is important to the overall effect, the actions occur. The sites of action include the cerebral cortex, the outer layer of the brain, that is responsible for functions including memory and perception. Actions also occur in the thalamus, that is responsible for conveying information to the cerebral cortex from different stimuli. The thalamus also has a role in the regulating actions that include the state of consciousness and sleeping.  Another important site of action is the reticular activating system, that has a similar role like the thalamus – that is, regulation of sleep. Anesthetics also work on the spinal cord, responsible for conveying information to and from the brain. In addition to this, the spinal cord is also responsible for control reflexes and has a role in motor actions.

Role of neurotransmitters and receptors in anesthetic effect

The mechanism of action includes role of different neurotransmitters and receptors. NMDA, acronym for N Methyl D Aspartic acid has a role in regulating memory, and certain anesthetics are known to have an effect on NDMA receptors.  Similarly, drugs also work on the 5-HT receptors, acronym for 5-hydroxytryptamine, is responsible for releasing other hormones and neurotransmitters. This is usually activated by serotonin, another neurotransmitter. Finally, anesthetics are also known to have an effect on glycine receptors that has a role in sleep.

Risks generally associated with general anesthesia

GA, as general anesthesia is commonly known is relatively safe, and may not pose any serious problems. Problems are usually linked to the procedure being performed, and the overall health condition of the patient. Most individuals who are healthy are unlikely to experience any kind of issues, especially individuals who do not drink heavily or smoke heavily. Risks are typically linked to elderly patients, and patients diagnosed with certain medical conditions that require complex procedures. Complications that may arise includes the possibility of postoperative confusion and possible pneumonia, while some may even end up with a stroke and suffer a heart attack; though this is limited only to specific high-risk categories.

The risks commonly associated with anesthesia at the time of surgical procedures includes habits such as drinking and smoking. Existing conditions like seizures, hypertension, obesity, high blood glucose levels and stroke are also possible complications. Patients diagnosed with obstructive sleep apnea, and renal ailments or liver issues are also at risk of developing complications. Any history of drug allergies is also a possible risk factor, apart from previous episodes of reactions when administered anesthesia.

Commonly reported side effects of anesthesia

All medications come with the risk of possible undesirable effects, and anesthesia is not an exception. As the drug is administered through one of two different means, there is the possibility of some unwanted outcomes. These effects are generally divided into mild effects and serious effects. The mild or moderate effects are typically frequently occurring in nature and resolve naturally, without the need for any medical intervention. These effects are known to resolve in a few days or weeks, or may also disappear when medications are stopped. In rare circumstances, it may be necessary to seek medical attention, when the condition is persistent or intense.

The serious or adverse effects require some kind of medical attention, and depending on the type of effects, may also require emergency attention. It is also necessary to note that a section of users may not experience any kind of effects whatsoever. It is therefore, important to understand that undesirable outcomes of medications will not affect every single user. Here is a short compilation of some of the commonly occurring effects This is not a complete or exhaustive compilation and is only intended to serve as a reference.

Frequently occurring mild effects

The patient is likely to be confused temporarily and may also experience some kind of memory loss. However, this is known to commonly affect only elderly patients. Another common effect is possible dizzy feelings, while some are known to experience nausea and vomiting sensations. The site of insertion of needle for IV may also cause bruising or soreness for some individuals and this a very mild outcome. Some are known to experience difficulty while urinating, and this could take a few days to resolve. Body temperature may dip at times and this could may make the patient feel cold or have shivering sensations. The throat may also turn sore, and this is attributed to the inserted tube.

Risks due to existing conditions or habits

As outlined above, certain categories of individuals are at higher risk of experiencing possible side effects of anesthesia. These effects include unintended intraoperative awareness, which is extremely rare, where the patient may find himself or herself aware during the operation. Typically, patients are to stop feeling all sensations after a certain period of administration of general anesthesia. However, patients in this condition may end up being aware, and may experience all pain sensations during the procedure. The complication in such procedures is the inability of the patient to indicate that he or she is feeling pain. Muscle relaxants administered during anesthesia, render the individual immobile and prevent the patient from making suitable gestures about the pain sensations.

A small section of individuals who experience such problems, may sometimes experience long term psychological effects. In most cases, this is short-lived, and is often limited to vague memories of the touch, or certain movements and possible sound heard during that stage. Various reasons are attributed to this possible complication.

Administration of IV sedation

As mentioned earlier, different types of sedation are used, and IV sedation is generally used for performing skin biopsies and for breast biopsies. The procedure is also chosen for minor surgical procedures, including fractures, apart from colonoscopy procedures. The latter refers to the insertion of a scope to perform diagnosis. Sedation is also used in dental procedures to extract tooth, and also when certain eye operations are performed.

Primary differences between general anesthesia and different types of sedation

This method is chosen for more complex and lengthier procedures including heart surgeries. Procedures are used in treating cancer also, although it comes with its inherent set of effects.  There are different degrees of sedations- for instance, mild sedation refers to the condition wherein the patient is awake, and the pain is not experienced. The second type is moderate sedation, wherein, the patient is sleeping, but may wake up soon. Deep sedation, the third type refers to the condition wherein the patient is in a deep sleep, and this option is used during complex procedures.

Under sedation, individuals are likely to feel drowsy, but may still be in soe form of consciousness, whereas under anesthesia, the patient is not conscious. When administered sedation, the individual does not typically require assistance for breathing, though at times respiratory assistance may be required in some cases. When administered anesthesia, the patient requires respiratory assistance, and this requires constant monitoring. Recovery from sedation is relatively faster than recovery from anesthesia.

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