anesthesia

Before the advent of anesthetics, in the middle of the 19th century, surgical operations were conducted with little or no pain relief. They were attended with great suffering and emotional distress of patients. But, not only patients, surgeons too suffered a lot of anxiety and distress. Today's medical procedures, starting from minor dental treatments, to complex surgeries, can not be imagined without anesthesia. In this lesson we will discuss:

• What is anesthesia
• What are anesthetics
• What anesthesiologists do
• Categories of anesthesia
• Is anesthesia safe

What is anesthesia?

Anesthesia or anaesthesia , which means "without sensation", is a state of controlled, temporary loss of sensation or awareness, induced for medical purposes. Anesthesia is given to patients so that surgery and other medical procedures can be carried out without pain and safely. 

Anesthesia can be simple, like numbing an area around a tooth during dental treatment, or something more complex, like using powerful drugs to cause unconsciousness.  

What are anesthetics?

Medications that cause anesthesia are called anesthetics. They work by blocking the signals that pass along the nerves to our brain. Normal sensations can be felt once when the drugs wear off. 

To produce anesthesia, doctors use drugs called anesthetics. Today are developed a collection of anesthetic drugs with different effects. These drugs include general, regional, and local anesthetics. The most common modern general anesthetics are mixtures of inhalable gases, which include nitrous oxide (laughing gas) and various derivatives of ether. 

Depending on what is needed, doctors can give anesthetics by inhalation, injection, topical lotion, spray, eye drops, or skin patch.

What do anesthesiologists do?

Doctors who are responsible for providing anesthesia to patients for operations and procedures are called anesthesiologists.

• they help people to make choices about types of anesthesia,
• discuss the risks of anesthesia with patients,
• they are responsible for administering anesthesia
• they are responsible for well-being and safety throughout the medical procedure.

 

Categories of anesthesia

There are three main categories of anesthesia used during surgery and other procedures:

• general anesthesia
• regional anesthesia
• local anesthesia

In some cases, patients may choose which type of anesthesia will be used.

General anesthesia 

With general anesthesia, patients are unconscious -“asleep”- and unable to feel any pain during the surgical procedure. It is often used for more serious operations.  General anesthesia usually uses a combination of intravenous drugs and inhaled gasses. It is the most common type of anesthesia.  

There are four stages of general anesthesia:

•  Induction - stage 1- is the period between the administration of induction agents and loss of consciousness. During this stage, the patient experiences sedation, analgesia (but can still feel pain), and eventually amnesia, and patients can carry on a conversation during this period. 
• Excitement stage - stage 2 - this period is marked by delirious and exciting activity, and patients may experience irregular respiration and heart rate, also, vomiting, uncontrolled movements. In this stage are used rapidly acting drugs aim to minimize the time in this stage and reach Stage 3 as fast as possible.
• Surgical anesthesia - stage 3 - in this stage, vomiting stops, the skeletal muscles relax, respiratory depression occurs, and eye movements slow and then stop. The patient is then unconscious and ready for surgery.
• Respiratory arrest - stage 4 - this stage is also known as overdose and occurs when too much anesthetic medication is given relative to the amount of surgical stimulation. This stage can be lethal without cardiovascular and respiratory support. The goal of the anesthesiologists is to keep patients into stage 3 for the duration of the operation.

Regional anesthesia 

Regional anesthesia is the use of local anesthetics to block sensations of pain from a large area of the body, such as an arm, leg, or abdomen. Regional anesthesia allows a procedure to be done on a region of the body without causing unconsciousness. There are several types of regional anesthesia including spinal anesthesia, epidural anesthesia, and various specific nerve blocks.

1. Spinal anesthesia involves the injection of a local anesthetic, with or without a narcotic, into the fluid that surrounds the spinal cord. This type of anesthesia is commonly used for cesarean sections and procedures of the lower extremities.
2. Epidural Anesthesia involves the injection of a local anesthetic, usually with a narcotic, into the epidural space. It can be given through either a needle or a catheter. This type of anesthesia is commonly used in labor and delivery and for procedures of the lower extremities. 
3. Nerve Blocks are used to block pain at a specific site. By injecting a local anesthetic into or around a specific nerve or group of nerves, pain relief can be localized to the site of pain. 

Regional and general anesthesia are often combined.

Local anesthesia 

Local anesthesia is usually a one-time injection of medicine that numbs a small area of the body. It is often used for minor outpatient procedures, like skin biopsy, stitching deep cut, some dental procedures. Local anesthesia lasts for a short period of time.

Is anesthesia safe?

While anesthesia is very safe, it can cause side effects during and after the procedure. Most of the side effects are minor and temporary, though there are some more serious effects to be aware of.