Episode #255 What You Need to Know Before Going Under

Hello and welcome back to the Anesthesia Patient Safety Podcast. My name is Alli Bechtel, and I am your host. Thank you for joining us for another show. Last week, we introduced the APSF’s Patient Guide to Anesthesia and Surgery. This guide was developed by the Anesthesia Patient Safety Foundation’s Patient Engagement Workgroup to help answer some of the most common questions that patients have before surgery and anesthesia. This is an important resource to help patients become more involved in their healthcare and learn more about what they can do to mitigate surgical risks and complications. Today, we going to be highlighting the excellent information that you can find in this Patient Guide using the Q&A format. Anesthesia professionals and members of the perioperative team can also use the guide to facilitate conversations with patients. This is a good podcast to share with patients too.

Before we dive further into the episode today, we’d like to recognize Medtronic, a major corporate supporter of APSF. Medtronic has generously provided unrestricted support to further our vision that “no one shall be harmed by anesthesia care”. Thank you, Medtronic – we wouldn’t be able to do all that we do without you!”

And now it’s time to highlight the Patient Guide to Anesthesia and Surgery. To follow along with us, head over to APSF.org and click on the Patient Safety Resources Heading. The fourth one up from the bottom is the Patient Guide to Anesthesia and Surgery. I will include the link in the show notes as well.

Let’s set the scene, you are in the preoperative anesthesia clinic and have just completed your history and physical exam. Now, it’s time to talk about the plan for anesthesia and the patient has some questions for you before their upcoming surgery with a general anesthetic. For my responses, I will be using the information from the Patient Guide.

[Patient] What’s a general anesthetic?

[Bechtel] “General aesthesia is a medically induced state of unconsciousness. It involves potent medications that suppress central nervous system activity and reflexes, leading to a complete loss of awareness and sensation. Your vital signs are closely monitored and we will use an airway device to support your breathing.”

[Patient] What are the medications that you are going to be using?

[Bechtel] “General anesthesia typically involves a mix of intravenous and inhaled anesthetics for balanced anesthesia. These drugs will vary based on the surgery and the needs of the patient. IV anesthetics are the most common drugs used for moderate to deep sedation and to induce general anesthesia. Most have rapid onset with effects that wear off quickly. This is ideal for shorter procedures.

Propofol is the most widely used general anesthetic because it acts quickly, reduces nausea, and is easy to control. It also has less “hangover” after-effects like confusion or fatigue. Anesthesia inducing agents (drugs that start anesthesia) like propofol are usually combined with other IV anxiolytics or analgesics.

Inhaled anesthetics are typically inhaled through a mask and delivered directly into the lungs with other gasses like oxygen. Anesthetic gasses can irritate the airway, so patients may experience a sore throat or dry mouth when waking from surgery. Inhaled anesthetics give anesthesia providers fast and easy control over depth of anesthesia. This makes them useful for maintaining anesthesia after IV induction.

Inhaled anesthetics are also used frequently in small children or in cases where IV access is difficult.

Nitrous oxide is the least potent inhaled anesthetic, which produces anxiolytic effects and mild to moderate pain relief. This makes it useful for sedation for dental work and before surgery. An example of an inhaled anesthetic is Sevoflurane.

[Patient] What happens if I wake up during the surgery?

[Bechtel] This is a very common concern. Many patients worry about waking up during surgery. This complication is known as anesthesia awareness or intraoperative awareness. However, with advanced monitoring and modern anesthesia techniques, it is a rare event.

Let’s go into a little more detail from the Patient Guide.

So, what is anesthesia awareness?

Anesthesia awareness happens when a patient becomes conscious during surgery. This can mean hearing conversations, feeling pressure or pain (in rare cases), or not being able to move. Most of the time patients only recall brief sensations or sounds. Patients are also more likely to remember anesthesia awareness several days after surgery than immediately afterward.

Anesthesia awareness is estimated to happen in only 1 or 2 out of 1,000 surgeries where general anesthesia is used. It is more common with certain surgeries like heart surgery or C-sections where lighter sedation is necessary to minimize complications. The patient’s health and other factors also play a role.

Anesthesia awareness occurs when the anesthesia is not strong enough to keep a patient fully unconscious during surgery. This can happen for several reasons, including:

1. Use of Muscle Relaxers: Muscle relaxers are often used during surgery to prevent movement and assist with placing a breathing tube. However, they can sometimes make it harder for anesthesia providers to notice if a patient is conscious.
2. Type of Surgery: Certain surgeries, like heart or emergency surgeries, have a higher risk of awareness. This is because anesthesia providers may need to use lighter anesthesia to maintain stable heart and lung function and reduce the risk of complications.
3. Patient Health: Patients with heart disease, respiratory problems, or other medical conditions may not tolerate deep anesthesia well.
4. Other Patient Factors: Patients with chronic pain or a history of substance abuse (especially alcohol or opioids) may be less sensitive to anesthetics. This is also true for patients who have had anesthesia awareness before.
5. Technical Issues: Equipment malfunctions or monitoring problems can result in not enough anesthesia.

Anesthesia providers take several steps to prevent patients from waking up during surgery:

• Pre-Surgery Check: Before surgery, the anesthesia provider reviews the patient’s medical history, current medications, and any past experiences with anesthesia. This helps them plan the right type and amount of anesthesia.
• Advanced Monitoring: During surgery, special monitors track vital signs and brain activity to ensure patients remain unconscious.
• Customized Anesthesia Plan: Anesthesia isn’t the same for everyone. The anesthesia provider adjusts the dosage and combination of drugs to fit each patient’s specific needs.

What Should You Do if You Experience Anesthesia Awareness?

If you believe you were aware during surgery, it’s important to tell your medical team right away. They can help you understand what happened and provide support. The incident can also be noted in your medical records to prevent future recurrence.

Anesthesia awareness can be deeply distressing for some patients. Speaking with a counselor can help manage any fear or anxiety that may arise.

[Patient] I’m feeling better about not waking up during the surgery, but how long will it take me to wake up after surgery? What if I have trouble waking up from the anesthesia?

[Bechtel] The time it takes to wake up from anesthesia can vary depending on a number of factors, including the type of anesthesia used. During deep sedation and general anesthesia, patients are always fully asleep. However, with moderate sedation, patients may remain awake or fall into a lighter sleep.

In general, patients start to wake up from anesthesia within a few minutes after the procedure is completed. Full recovery takes from minutes to hours. While waking up from anesthesia, patients may experience side effects such as nausea, dizziness, and confusion. These side effects are usually temporary. They will go away as the effects of anesthesia wear off.

If a patient has trouble waking up from general anesthesia, it could be due to several factors. These include:

1. Type and Dose of Anesthesia: Different anesthetic drugs work for varying lengths of time. Higher doses or long-lasting drugs can cause a delayed wake-up time.
2. Length of Surgery: Being under anesthesia for a longer time can result in a longer recovery period.
3. Drug Metabolism: Some people metabolize anesthetic drugs more slowly. This can extend recovery time.
4. Age and Overall Health: Older adults and those with certain health conditions may take longer to wake up.
5. Complications: In rare cases, complications such as low blood pressure or low oxygen levels during surgery can lead to a slower recovery.

Here is a little more information about Delayed Emergence from Anesthesia from the Patient Guide.

It is not uncommon for some patients to experience a delay in waking up from anesthesia. This is called delayed emergence. This typically occurs when it takes longer than 30 to 60 minutes for a patient to regain consciousness, depending on the procedure. In some instances, medications may be administered to promote wakefulness. These counteract the residual effects of the anesthetics used during surgery.

It is important to let medical professionals know if you had a difficult time waking up from anesthesia in the past, your health history, and any medications you are taking. Certain medical conditions and medications can contribute to delayed emergence.

After waking up from anesthesia, patients typically spend some time in the recovery room. Vital signs and overall condition are monitored until patients are ready to go home or moved to a hospital room. Due to lingering side effects, patients who have received moderate or deep sedation, or general anesthesia, will need someone to drive them home.

[Patient] What about the side effects of anesthesia?

[Bechtel] Anesthesia is a critical part of modern medicine, allowing patients to safely undergo major surgeries and procedures. However, like any medical intervention, it can cause side effects or complications. These depend on the type of surgery, the patient’s age, health, and medical history. Knowing what to expect can help patients and anesthesia providers prepare and manage these adverse effects.

General anesthesia puts patients into a deep sleep so they don’t feel pain during surgery. While generally safe, it can lead to temporary side effects or, more rarely, serious complications.

A side effect is a mild, expected, and usually temporary result of anesthesia. A complication is more serious, can last longer, and may require extra treatment.

Common Side Effects.

• Drowsiness or Fatigue: Very common after anesthesia; can last for several hours.
• Dry Mouth: Caused by drugs that reduce saliva production.
• Sore Throat or Hoarseness: Common if a breathing tube is used. The throat may feel scratchy, or the voice may sound different.
• Nausea and Vomiting (PONV): Affects about 1 in 3 patients. It usually resolves within a few hours and can be treated with medication.
• Itching: Often caused by opioid medications used during or after surgery.
• Shivering or Chills (Hypothermia): A common response as the body rewarms after surgery.
• Dizziness: Often caused by low blood pressure, especially when standing up.
• Confusion or Memory Problems (Temporary): Patients may feel foggy or have trouble remembering. This usually lasts a few hours to a couple days. It is more common in older adults.
• Muscle Aches: Caused by muscle relaxants or the way the body was positioned during surgery.
• Headache: May be due to dehydration, stress, or the anesthesia itself.
• Difficulty Urinating: Temporary and more likely after certain surgeries or when opioids are used.
• Emergence Delirium: Some people, especially children, may wake up confused, upset, or acting strangely. This usually resolves quickly with calm support.

Common Neurocognitive Complications.

• Postoperative Delirium: A state of confusion, disorientation, and agitation that can happen in the first few days after surgery and may last up to a week. It’s common in older adults and those with memory problems.
• Postoperative Cognitive Dysfunction: Problems with memory, focus, or clear thinking that can last weeks or months after surgery. It’s more common in older patients and after major surgery.

Rare Complications.

• Respiratory Problems: Includes trouble breathing or lung infections like pneumonia.
• Allergic Reactions: Can range from a mild rash to a severe, life-threatening reaction called anaphylaxis.
• Malignant Hyperthermia: A dangerous reaction to certain anesthesia drugs, causing high fever, muscle stiffness, and other serious issues. It needs immediate treatment.
• Nerve Damage: can occur if a patient is positioned incorrectly during surgery.
• Anesthesia Awareness: patients may regain some awareness during surgery, often due to insufficient anesthesia.
• Death: Extremely rare and usually related to pre-existing health conditions or complications during surgery.

When to Seek Medical Attention.

Most adverse effects of anesthesia are mild and go away on their own. However, patients should contact their healthcare provider if they experience:

• Severe or ongoing nausea and vomiting.
• Trouble breathing or chest pain.
• Signs of infection, such as fever, redness, or swelling at the surgical site.
• Severe headaches or confusion that don’t improve.
• Numbness, weakness, or other unusual symptoms that last longer than expected.

How to Reduce the Risk of Side Effects & Complications.

To lower your risk, patients should:

1. Discuss Their Medical History: Tell your anesthesia provider about any health conditions, allergies, or medications you’re taking.
2. Follow Pre-Surgery Instructions: This may include fasting or adjusting medications before surgery. Always ask your anesthesia provider before starting or stopping any medications.
3. Avoid alcohol, Smoking, and Recreational Drugs: These can interfere with anesthesia, slow healing, and increase complications. Patients should disclose recent use—even if it’s uncomfortable—so their team can adjust your care safely.
4. Ask Questions: Understand the type of anesthesia being used and its potential side effects.
5. Follow Post-op Instructions: Take prescriptions as directed, stay hydrated, and resume activity as approved by their healthcare team.
6. Report Side Effects: Contact their provider if they experience unusual or concerning symptoms after surgery. Treating symptoms early may help prevent more serious complications.

[Patient] Can I be allergic to anesthesia?

[Bechtel] When people express concerns about being “allergic to anesthesia,” they might be referring to different types of reactions. Some of these may be allergies, while others are side effects or non-allergic responses.

First, let’s talk about Allergic Reactions including the following:

• IgE-Mediated Allergic Reactions – IgE antibodies are produced by the immune system causing the release of histamine. These are known as “classic allergies” and generally occur within minutes of being exposed to an allergen. IgE allergies can range from mild symptoms to an acute, severe reaction called anaphylaxis. Because they can become life threatening, all allergy symptoms to anaesthetic drugs should be taken seriously. Symptoms include:
  • Hives or Flushing.
  • Swelling.
  • Difficulty breathing.
  • Dizziness or fainting due to low blood pressure.
  • Rapid heart rate.
• Non-IgE-Mediated Allergic Reactions – Some allergic reactions don’t involve IgE antibodies but involve other parts of the immune system such as T-cells. Non-IgE allergies are very rarely life-threatening but can still cause troubling symptoms including:
  • Rashes.
  • Vomiting, diarrhea or stomach pain.
  • Fatigue.
  • Fever.
  • Joint pain.

The Most Common Anesthesia Drug Allergies are Neuromuscular Blocking Agents & NSAIDS
Other Common Surgical Allergies include Latex, Antibiotics, and Contrast Dyes.

Another type of reaction is a Non-Allergic Reaction called pseudoallergic reaction.

• These reactions look like allergic symptoms (such as hives, flushing, or low blood pressure) but don’t involve antibodies or the immune system. They are due to the direct release of histamine or other substances from cells like mast cells. Pseudoallergies are fairly common and rarely severe.
• Side Effects include Nausea, vomiting, dizziness, sore throat (from intubation), muscle aches, and shivering are common side effects of anesthesia. These symptoms typically appear after waking up from surgery, unlike an acute allergic reaction, which usually happens immediately after exposure to a drug.

Other Adverse Reactions include the following:

• Malignant Hyperthermia – A rare but serious reaction to some anesthetic drugs, causing a fast rise in body temperature and severe muscle contractions. This is not an allergic reaction but a genetic condition that requires quick treatment.
• Local Anesthetic Systemic Toxicity (LAST) – A rare but severe reaction that occurs when local anesthetics are absorbed into the bloodstream in high amounts, causing nervous system and heart problems.

Let’s return to allergic reactions. Several factors can increase the risk of an allergic reaction to anesthesia. These include:

• History of allergies.
• Personal or family history of reactions to anesthesia.
• Certain medical conditions like asthma, eczema, or mast cell disorders.

Before surgery, it is crucial for patients to share their full medical history with the healthcare team. This includes any known drug allergies or previous reactions to anesthesia. The doctor may recommend pre-operative tests, such as skin tests, to identify allergens in anesthetics.

If an allergy is detected, the anesthesia provider can select different drugs and may adjust the anesthesia plan to minimize the risk of a reaction. During surgery, the medical team will closely monitor the patient’s vital signs for any adverse reactions.

[Patient] Can I Have an Allergy to Anesthesia after surgery, like Hours or Days later?

[Bechtel] Although less common, patients may experience an allergic reaction to anesthesia hours or even days after surgery. These delayed allergies, known as non-IgE-mediated allergic reactions, involve other parts of the immune system, such as T-cells, rather than IgE antibodies. This causes symptoms to develop more slowly.

Patients may experience symptoms such as skin rashes, fever, joint pain, or swelling, which could indicate a delayed allergic reaction. However, these symptoms might also be due to lingering 1) side effects from anesthesia and surgery or 2) pseudoallergic reactions to new medications or dietary changes. Although these non-IgE reactions are typically not severe, they can still cause distress and should be reported to a healthcare provider.

[Patient] Can I Have an Allergy to Dental Anesthetics?

[Bechtel] Like with all anesthetics, allergies from dental anesthetics are rare. Dental anesthesia mainly uses local anesthetic drugs. Allergic reactions, when they do occur, are often from components like preservatives in the anesthetic. Sulfites are often used to preserve epinephrine, a common additive drug used in local anesthetics. Patients may also have expected side effects from the local anesthetic itself. These are usually mild and include pain, redness, or swelling. In rare cases, patients may experience local anesthetic systemic toxicity (LAST). This is a serious complication that can result in dizziness, confusion, loss of consciousness, irregular heartbeat and large changes in blood pressure.

Patients should discuss any concerns about possible reactions with their dentist or anesthesia provider. They can take precautions to minimize risks and keep patients comfortable.

We are going to wrap up our preoperative visit for today, but there is still so much information in the APSF’s Patient Guide to Anesthesia and Surgery that we hope you and your patients will check out. Increasing information and sharing this knowledge is another important way to help keep patients safe during anesthesia care.

If you have any questions or comments from today’s show, please email us at [email protected]. Please keep in mind that the information in this show is provided for informational purposes only and does not constitute medical or legal advice. We hope that you will visit APSF.org for detailed information and check out the show notes for links to all the topics we discussed today.

Submissions are now open for the 2025 APSF Trainee Quality Improvement Patient Safety Recognition Program. This is open for all US and Canadian anesthesia professionals in training including physician anesthesiology residents, nurse anesthesia students, and student anesthesiologist assistants. Winners will be notified in August and be sponsored to attend the 2025 Stoelting Conference in Chicago, Illinois to share their work and network with attendees. Submissions will be accepted as a document or audio or video recording. The submission deadline is June 1, 2025, at 11:59pm EST. I will include the link in the show notes for more information! This is an exciting opportunity that you do not want to miss!!

Until next time, stay vigilant so that no one shall be harmed by anesthesia care.

© 2025, The Anesthesia Patient Safety Foundation