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Airway Management: Anatomy of the Airway

General Anesthesia. Medical manipulation.

Airway management is a crucial aspect of medical practice, particularly in emergency situations, anesthesia, and critical care, making it essential for healthcare providers to understand the anatomy of the airway. The airway consists of both upper and lower respiratory structures, and each part plays a significant role in the passage of air from the environment to the lungs.

Upper airway anatomy consists of several key structures relevant for airway management due to their roles in directing air to the lungs while also filtering, warming, and humidifying it. The first part of the upper airway is the nasal cavity, where air is first drawn in. The nasal passages are lined with mucous membranes that trap debris and pathogens before they can enter the lungs. From the nasal cavity, air passes through the nasopharynx, the upper portion of the throat located behind the nose. The nasopharynx is followed by the oropharynx, which serves as a passageway for both air and food. It is located behind the mouth and contains structures such as the uvula, tonsils, and the base of the tongue. Next, at the laryngopharynx, the pathways for air and food diverge. The larynx, or voice box, sits at the junction of the laryngopharynx and the trachea and contains the vocal cords. It is involved in breathing, swallowing, and vocalizing. The epiglottis, a flap of tissue located above the larynx, acts as a protective mechanism by closing off the airway during swallowing to prevent food or liquids from entering the trachea ^1–3.

The lower airway begins at the trachea, a rigid, cartilaginous tube lined with mucous membranes and cilia that help trap and move foreign particles out of the airway. It extends from the larynx down to the level of the carina, where it bifurcates into the left and right mainstem bronchi. The right mainstem bronchus is shorter and more vertically oriented than the left, which makes it more prone to accidentally being intubated in emergency situations. Each mainstem bronchus branches into secondary and tertiary bronchi, further dividing into smaller airways known as bronchioles—the smallest branches of the airways that lead to the alveoli, which are surrounded by a network of capillaries where oxygen is transferred into the bloodstream and carbon dioxide is removed from the body ^1,2,4.

Airway management requires that the patient’s airway remains open and unobstructed. In an emergency, providers may need to secure the airway through interventions such as endotracheal intubation, where a tube is inserted into the trachea to maintain airflow. In addition, in situations of respiratory distress or failure, the management of the airway can include using mechanical ventilation to assist or replace normal breathing. Effective airway management is essential not only for maintaining oxygenation but also for preventing complications like aspiration, which can lead to pneumonia or other respiratory issues. A thorough understanding of the anatomy of the airway is vital for healthcare providers, as it enables them to quickly assess the situation and make informed decisions about the best approach to airway management and the maintenance of adequate respiratory function ^5–7.

References

1. What Are Your Airways? Cleveland Clinic https://my.clevelandclinic.org/health/body/airway.

2. Ball, M., Hossain, M. & Padalia, D. Anatomy, Airway. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2025).

3. Upper Respiratory Airways. Physiopedia https://www.physio-pedia.com/Upper_Respiratory_Airways.

4. Lower respiratory tract: MedlinePlus Medical Encyclopedia Image. https://medlineplus.gov/ency/imagepages/19379.htm.

5. Avva, U., Lata, J. M. & Kiel, J. Airway Management. in StatPearls (StatPearls Publishing, Treasure Island (FL), 2025).

6. Jacobs, L. M. The Importance of Airway Management in Trauma. J Natl Med Assoc 80, 873–879 (1988).

7. Trauma Service : Airway management. https://www.rch.org.au/trauma-service/manual/airway-management/.

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Treatment of Fluid Retention During Surgery

Close-up of IV drip bag in emergency room. Medicine is passing through pipe from intravenous drip. It is in hospital.

Fluid retention during surgery poses a significant challenge to perioperative management because excessive fluid accumulation can impair organ function and wound healing and increase morbidity. Effective strategies for managing fluid retention during surgery involve a combination of precise fluid administration, pharmacologic intervention, and vigilant monitoring of physiological parameters to maintain hemodynamic stability while avoiding complications such as edema and electrolyte imbalance.

Surgery causes significant physiological stress that triggers the release of hormones such as aldosterone and antidiuretic hormone (ADH). These hormones promote fluid retention by increasing sodium and water reabsorption in the kidneys. At the same time, surgical trauma activates an inflammatory response that increases capillary permeability and allows fluid to leak into the tissues. This fluid shift can cause swelling (edema) and reduce circulating blood volume. To address these challenges, clinicians can use balanced crystalloids instead of saline as intravenous (IV) fluids. Balanced crystalloids prevent complications such as hyperchloremic acidosis that can occur with excessive saline use (1). Advanced hemodynamic monitoring tools, including cardiac output and stroke volume analysis, help guide fluid administration to maintain balance without overloading or depleting the patient’s fluid reserves.

Pharmacologic intervention is critical in the management of fluid retention during and after surgery, especially in patients predisposed to complications such as those with heart failure or chronic kidney disease. Diuretics, such as furosemide, are commonly used to promote urinary excretion of excess fluid. However, they must be used with caution, as excessive diuresis can lead to dehydration and electrolyte disturbances, including low potassium or sodium levels. Electrolyte monitoring and repletion are often required to address these issues (2). In cases of significant fluid retention or dilutional hyponatremia, vasopressin receptor antagonists offer a targeted solution. These drugs block fluid retention without disrupting sodium balance, making them particularly useful in complex surgeries such as liver transplantation or cardiac surgery (3).

Minimizing surgical trauma is another effective way to reduce fluid retention. Minimally invasive techniques, such as laparoscopic or robotic surgery, cause less tissue damage than traditional open surgery. This reduces the inflammatory response and associated capillary leakage, resulting in better fluid management and faster recovery. Perioperative measures such as maintaining normothermia also play a vital role. Hypothermia during surgery can impair renal function and exacerbate fluid retention through vasoconstriction and hormonal imbalance. Techniques such as warming blankets, heated IV fluids, and active warming devices help maintain body temperature and mitigate these effects.

For severe cases of fluid retention, especially in patients with acute kidney injury or refractory fluid overload, continuous renal replacement therapy (CRRT) is an advanced treatment option. CRRT is a form of dialysis that removes excess fluid and toxins while maintaining electrolyte balance. It is particularly useful in critically ill patients who cannot tolerate traditional diuretic therapy. Early implementation of CRRT has been shown to improve outcomes by allowing gradual fluid removal without causing hemodynamic instability (4).

In conclusion, the management of fluid retention during surgery is a multifaceted process that requires precision and adaptability. By combining tailored fluid therapy, pharmacologic interventions, minimally invasive techniques, and innovative monitoring, clinicians can effectively address the challenges posed by fluid retention. These evidence-based strategies improve surgical outcomes, enhance recovery, and reduce the risk of complications, demonstrating the importance of a proactive approach to perioperative care.

References

Myburgh JA, Mythen MG. Resuscitation fluids. N Engl J Med. 2013;369(13):1243-1251. doi:10.1056/NEJMra1208627
Kellum JA, Lameire N; KDIGO AKI Guideline Work Group. Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1). Crit Care. 2013;17(1):204. Published 2013 Feb 4. doi:10.1186/cc11454
Schrier RW. Water and sodium retention in edematous disorders: role of vasopressin and aldosterone. Am J Med. 2006;119(7 Suppl 1):S47-S53. doi:10.1016/j.amjmed.2006.05.007
Hoste EA, Bagshaw SM, Bellomo R, et al. Epidemiology of acute kidney injury in critically ill patients: the multinational AKI-EPI study. Intensive Care Med. 2015;41(8):1411-1423. doi:10.1007/s00134-015-3934-7

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Factors Affecting Propofol Injection Pain

Propofol is a commonly used intravenous anesthetic, popular for its rapid onset and effectiveness in inducing sedation and analgesia. However, one of the challenges associated with propofol administration is propofol injection pain. This discomfort, which occurs in 28%–90% of patients according to studies of different patient groups,1 can be distressing and complicates the overall experience of medical procedures. Several different factors, such as pharmacodynamics, the rate of injection, and patient-specific variables, can all play significant roles in the intensity and frequency of propofol injection pain. Understanding the mechanisms underlying this pain is crucial for improving surgical flow and patient outcomes in clinical settings.

A 2008 study found transient receptor potential ankyrin 1 (TRPA1), a nonselective ligand-gated cation channel, is heavily involved in the activation of peripheral nerve endings by general anesthetics, including propofol. TRPA1 is an ion channel on cell plasma membranes that is associated with pain perception; it is known as a biological sensor for chemical irritants, oxidative stress, and colder temperatures. In wild-type mice, propofol was shown to produce pain-related behaviors. In contrast, nocifensive behavior was absent in TRPA1–/− mice, but not in TRPA1+/− littermates. Propofol, when injected into the femoral artery, evoked reflex muscle activity in TRPA1+/− but not in their TRPA1–/− counterparts. These results indicate having one allele of the TRPA1 gene is sufficient for propofol-induced injection pain.2

A later study found another potential causative agent: transient receptor ankyrin vanilloid 1 (TRPV1), the excitatory ion channel of the transient receptor potential family that is activated by noxious stimuli such as capsaicin, protons, and excessive heat. The study, performed on human cell TRPA1 and TRPV1, revealed the two molecules mediate propofol-induced injection pain through increasing calcium ions in the dorsal root ganglion.3 This molecular release induces vascular leakage and is thought to contribute to neurogenic inflammation in the periphery and central sensitization in the spinal dorsal horn.1

The speed of injection and site of administration are also factors influencing propofol injection pain. Slow injection causes more pain than rapid bolus since slow injection increases the concentration and duration of exposure of propofol to the vein wall, while rapid injection quickly clears the drug from the vein and replaces it with blood.4 It is suggested the painful sensation originates from neural elements within the vein wall by way of free afferent nerve endings. Propofol

administration can release kininogen, the precursor to bradykinin, which supports vasodilation and hyper-permeability. Prolonged propofol administration may increase interaction between the drug and bradykinin, causing pain, swelling, and inflammation.5 In a prospective cohort study where patients were separated by age and gender, male subjects receiving propofol through the top of the hand were much less likely to experience propofol injection pain than their female counterparts (45.7% vs 74%). However, all groups demonstrated a significant decrease in propofol injection pain when the site of administration changed from the dorsum of hand to the antecubital fossa, i.e., the inside of the elbow (12.5% for men and 37% for women).6

While propofol remains a widely used and highly effective anesthetic, propofol injection pain is an important side effect to research and address in order to improve patient comfort. The multifaceted nature of propofol injection pain, involving both pharmacological and procedural factors, underscores the complexity and necessity of managing this side effect. Although there has been some research conducted to identify key contributors to this pain, it remains an area that requires deeper investigation. Additionally, much of the research to date is based on older datasets, highlighting the need for more contemporary studies to build on earlier findings.

References

1. Desousa, Kalindi A., “Pain on Propofol Injection: Causes and Remedies.” Indian Journal of Pharmacology, vol. 48, no. 6, 2016, p. 617. https://doi.org/10.4103/0253-7613.194845

2. Matta, José A., et al. “General Anesthetics Activate a Nociceptive Ion Channel to Enhance Pain and Inflammation.” Proceedings of the National Academy of Sciences, vol. 105, no. 25, June 2008, pp. 8784–89. https://doi.org/10.1073/pnas.0711038105

3. Fischer, Michael J. M., et al. “The General Anesthetic Propofol Excites Nociceptors by Activating TRPV1 and TRPA1 Rather than GABAA Receptors.” The Journal of Biological Chemistry, vol. 285, no. 45, Sept. 2010, p. 34781. https://doi.org/10.1074/jbc.M110.143958

4. Scott, R. P., et al. “Propofol: Clinical Strategies for Preventing the Pain of Injection.” Anaesthesia, vol. 43, no. 6, June 1988, pp. 492–94. https://doi.org/10.1111/j.1365-2044.1988.tb06641.x

5. Leff, Phillip J., et al. “Characteristics That Increase the Risk for Pain on Propofol Injection.” BMC Anesthesiology, vol. 24, no. 1, May 2024, p. 190. https://doi.org/10.1186/s12871-024-02573-y.

6. Kang, Hye-Joo, et al. “Clinical Factors Affecting the Pain on Injection of Propofol.” Korean Journal of Anesthesiology, vol. 58, no. 3, Mar. 2010, pp. 239–43. https://doi.org/10.4097/kjae.2010.58.3.239

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Anesthetics with the Least Hemodynamic Effects

Anesthetics with the Least Hemodynamic Effects

Certain anesthetic agents can have significant effects on the cardiovascular system, causing changes in heart rate, blood pressure, and cardiac output. For patients with cardiovascular disease or other conditions that make them sensitive to hemodynamic fluctuations, choosing anesthetics with the least hemodynamic effects is essential for reducing the risk of complications.

Hemodynamic effects refer to changes in the circulatory system, particularly those related to heart function and blood flow. Anesthetic agents can cause a variety of hemodynamic changes, including hypotension, bradycardia, or tachycardia 1–3. These effects can be dangerous for patients with compromised cardiovascular function, such as those with coronary artery disease, heart failure, or severe hypertension. For these patients, anesthetics that have the least hemodynamic effects are preferred to reduce the risk of perioperative cardiovascular events, including heart attack and stroke.

Several anesthetic agents are known for their minimal effects on the cardiovascular system, making them ideal for use in high-risk patients. These agents include certain intravenous and inhaled anesthetics as well as local anesthetics used for regional blocks.

Dexmedetomidine is a sedative and anesthetic agent that has gained popularity due to its ability to provide sedation and pain relief with minimal hemodynamic effects. It acts as an alpha-2 adrenergic agonist, leading to a reduction in sympathetic nervous system activity, which can help prevent significant fluctuations in heart rate and blood pressure. Unlike other sedatives, such as propofol, dexmedetomidine tends to cause only mild hypotension and bradycardia without suppressing respiratory function, making it an excellent choice for patients with cardiovascular risk factors 4.

Etomidate is an intravenous anesthetic agent commonly used for induction in patients with hemodynamic instability. It is known for its ability to induce anesthesia rapidly without causing significant changes in heart rate, blood pressure, or cardiac output. Unlike other induction agents like propofol or thiopental, which can cause hypotension, etomidate maintains cardiovascular stability, making it especially useful in patients with heart failure or shock 5.

Midazolam, a benzodiazepine, is another agent with minimal hemodynamic effects. It is often used for preoperative sedation and as an adjunct in anesthesia protocols. While midazolam can cause mild hypotension in some cases, it generally has a favorable cardiovascular profile compared to other sedatives and is often used in patients with cardiovascular concerns. It is commonly administered alongside other agents for balanced anesthesia 6.

Sevoflurane is a widely used inhaled anesthetic with a relatively low impact on the cardiovascular system compared to other volatile anesthetics. It causes less myocardial depression and minimal vasodilation, leading to more stable blood pressure and heart rate during anesthesia. Sevoflurane is particularly useful for maintaining anesthesia in patients who require careful management of their cardiovascular status 7.

Local anesthetics used for regional anesthesia, such as bupivacaine and ropivacaine, have minimal systemic hemodynamic effects when used in appropriate doses 8,9.

For patients with cardiovascular concerns or those at risk of hemodynamic instability, selecting anesthetics with the least effects on blood pressure, heart rate, and cardiac output is essential for ensuring a safe surgical experience.

References

1. Barker, S. J., Gamel, D. M. & Tremper, K. K. Cardiovascular effects of anesthesia and operation. Critical Care Clinics (1987). doi:10.1016/s0749-0704(18)30545-1

2. Ebert, T. J. Sympathetic and hemodynamic effects of moderate and deep sedation with propofol in humans. Anesthesiology (2005). doi:10.1097/00000542-200507000-00007

3. Hemodynamic management during anesthesia in adults – UpToDate. Available at: https://www.uptodate.com/contents/hemodynamic-management-during-anesthesia-in-adults.

4. Dexmedetomidine – StatPearls – NCBI Bookshelf. Available at: https://www.ncbi.nlm.nih.gov/books/NBK513303/.

5. Etomidate – StatPearls – NCBI Bookshelf. Available at: https://www.ncbi.nlm.nih.gov/books/NBK535364/.

6. Midazolam – StatPearls – NCBI Bookshelf. Available at: https://www.ncbi.nlm.nih.gov/books/NBK537321/.

7. Sevoflurane – StatPearls – NCBI Bookshelf. Available at: https://www.ncbi.nlm.nih.gov/books/NBK534781/.

8. Rutten, A. J. et al. Hemodynamic and central nervous system effects of intravenous bolus doses of lidocaine, bupivacaine, and ropivacaine in sheep. Anesth. Analg. (1989). doi:10.1213/00000539-198909000-00004

9. Hashemian, M. et al. Comparison of Ropivacaine versus Bupivacaine in Spinal-Induced Hypotension in Preeclampsia Patients: A Randomized Control Trial. Anesthesiol. Pain Med. 14, (2024). doi: 10.5812/aapm-14264

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Fall vs. Spring Allergies

Fall vs. Spring Allergies

Allergies are a common seasonal issue that affect millions of people worldwide. While many associate allergies primarily with the spring, fall allergies can be just as troublesome. Both seasons bring specific allergens that can trigger symptoms such as sneezing, runny nose, itchy eyes, and congestion.

Spring allergies are predominantly triggered by pollen. As trees, grasses, and flowers begin to bloom in warming weather, they release large amounts of pollen into the air. Common culprits include trees like oak, birch, maple, and various grasses. Pollen levels typically peak in the morning and on dry, windy days when pollen is easily dispersed through the air.

For those with pollen allergies, springtime can be particularly challenging. Pollen grains are small and lightweight, allowing them to travel long distances and penetrate deep into the respiratory system. When an allergic person inhales pollen, their immune system mistakenly identifies it as a harmful substance, triggering a cascade of symptoms. This condition, commonly known as hay fever or allergic rhinitis, can significantly affect daily life, leading to fatigue and decreased productivity ^1–3.

Fall allergies are primarily caused by ragweed pollen, mold, and dust mites. Ragweed is a resilient plant that grows abundantly in many regions, and it produces a significant amount of pollen from late summer into the fall. Ragweed pollen can travel hundreds of miles in the air, making it difficult to escape, even in urban areas.

Mold is another common allergen in the fall, especially in damp and decaying leaves, soil, and compost piles. As temperatures cool and humidity levels rise, mold spores proliferate, becoming airborne and triggering allergic reactions. Dust mites, although present year-round, tend to become more problematic in the fall when homes are closed up and heating systems are turned on, stirring up dust and allergens trapped inside ^4,5.

Tree and grass pollen are the main spring allergens, while ragweed pollen, mold, and dust mites are the primary fall allergens. Spring allergies often cause more upper respiratory symptoms, such as sneezing, itchy eyes, and a runny nose while fall allergies can lead to more lower respiratory symptoms, as well as trigger indoor allergies as people spend more time inside with closed windows, increasing exposure to dust mites and mold ^6,7.

Regardless of the season, managing allergies effectively requires a combination of strategies. First, limiting exposure to allergens is crucial. During peak pollen seasons, keep windows closed and use air conditioning with a clean filter. For mold, regularly clean and dry areas prone to dampness, such as basements and bathrooms ⁸.

Second, environmental control measures can be taken. For example, individuals can use high-efficiency particulate air (HEPA) filters to reduce airborne allergens in the home. Regularly washing bedding and vacuuming with a HEPA filter vacuum cleaner can also minimize exposure to dust mites ⁹.

Finally, over-the-counter antihistamines, decongestants, and nasal corticosteroids can help alleviate symptoms. For more severe cases, a doctor may prescribe stronger medications or recommend allergy shots (immunotherapy) to build tolerance to specific allergens ¹⁰.

Both fall and spring allergies present unique challenges, but understanding their causes and symptoms can help sufferers manage their condition more effectively. Whether dealing with pollen in the spring or ragweed and mold in the fall, taking proactive steps can reduce the impact of seasonal allergies and improve overall quality of life.

References

1. The Spring Allergy: What Causes Sneezing and Runny Eyes. Available at: https://www.webmd.com/allergies/spring-allergies.

2. Spring allergies: Causes, management, and home remedies. Available at: https://www.medicalnewstoday.com/articles/spring-allergies.

3. Allergic Rhinitis (Hay Fever): Symptoms & Treatment. Available at: https://my.clevelandclinic.org/health/diseases/8622-allergic-rhinitis-hay-fever.

4. Fall Allergies: Symptoms and 8 Causes. Available at: https://health.clevelandclinic.org/remedies-for-fall-allergies.

5. Fall Allergies. Available at: https://www.webmd.com/allergies/fall-allergy-relief.

6. Fall vs. spring allergies: What is the difference? Available at: https://www.medicalnewstoday.com/articles/fall-allergies-vs-spring#symptoms.

7. The Difference Between Spring and Fall Allergies – Coastal Ear, Nose & Throat. Available at: https://coastal-ent.com/posts/allergies/the-difference-between-spring-and-fall-allergies/.

8. What triggers seasonal allergies? | NIH MedlinePlus Magazine. Available at: https://magazine.medlineplus.gov/article/what-triggers-seasonal-allergies.

9. The 8 Best Air Purifiers for Allergies of 2024. Available at: https://www.verywellhealth.com/best-air-purifiers-for-allergies-4170072.

10. Seasonal Allergies (Allergic Rhinitis) > Fact Sheets > Yale Medicine. Available at: https://www.yalemedicine.org/conditions/seasonal-allergies.

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Cryoneurolysis for Pain Relief

Cryoneurolysis for Pain Relief

Cryoneurolysis, also known as cryoablation, is a pain management technique that involves using extreme cold to temporarily block nerve conduction, leading to significant pain relief (Biel, et al., 2023). This minimally invasive procedure is gaining popularity for its effectiveness in treating certain acute and chronic pain conditions. Interestingly, cryoneurolysis is a technique that dates back thousands of years to the ancient Greeks and Egyptians (Biel, et al., 2023).

The procedure involves applying extreme cold to a specific anatomical area and the nerves that innervate it. This disrupts the conduction of pain signals to the spinal cord and brain (Biel et al., 2023). A probe cooled by liquid nitrogen or nitrous oxide creates temperatures as low as -20 to -100 degrees Celsius (Ilfeld & Finneran, 2020). The low temperatures of cryoneurolysis disrupt the nerve’s ability to transmit pain signals to the spinal cord and the brain, leading to pain relief. Unlike other forms of ablation, cryoneurolysis targets the nerve without necessarily causing permanent damage. The nerve’s ability to regenerate means that normal function can return over time, typically within a few months.

Cryoneurolysis is used to provide pain relief for various conditions, including chronic pain, post-surgical pain, neuropathic pain, and cancer pain. Chronic conditions like osteoarthritis, especially in the knee, can benefit from cryoneurolysis. Patients recovering from surgeries like total knee arthroplasties, shoulder arthroplasties, thoracotomies, and mastectomies often face considerable pain. This technique can be used intraoperatively, and multiple randomized, controlled trials have shown shorter hospitalization times and fewer opioid-related complications for patients undergoing thoracotomy (Ilfeld & Finnernan, 2020). Cryoneurolysis provides an effective solution by numbing the nerves in the affected area, facilitating a smoother recovery process (Biel et al., 2023) Conditions like postherpetic neuralgia from shingles or complex regional pain syndrome can also be treated with cryoneurolysis, offering pain relief where other treatments have failed. It is also beneficial in managing pain associated with certain cancers (Biel et al., 2023).

As a minimally invasive procedure, cryoneurolysis involves a small incision for inserting the cryoprobe, reducing the risk of complications and ensuring a quicker recovery time compared to more invasive surgical options. It allows for the precise targeting of the affected nerves, minimizing damage to surrounding tissues and reducing side effects. The use of ultrasound imaging enables precise application to specific peripheral nerves and deeper nerve structures that would be more dangerous to access otherwise (Biel et al., 2023). The temporary nature of the nerve block means normal nerve function typically returns within a few months, though repeat treatments will be necessary depending on the etiology of the patient’s pain (Biel et al., 2023). Additionally, by providing significant pain relief, cryoneurolysis can reduce the need for opioids and other pain medications, lowering the risk of dependency and side effects associated with long-term medication use (Bittman et al., 2019).

The cryoneurolysis procedure is usually performed on an outpatient basis under local anesthesia. Using imaging guidance, such as ultrasound or fluoroscopy, the physician inserts the cryoprobe near the targeted nerve (Bittman et al., 2019). The area is then cooled to the desired temperature for a specific period. Patients may experience some initial discomfort or bruising at the treatment site, but these symptoms typically resolve within a few days. Rarely, patients may have bleeding or infection. (Biel et al., 2023). Most patients can return to their normal activities within a short period (Biel et al., 2023).

Ultimately, cryoneurolysis offers a promising alternative for pain management, particularly for patients who have not found relief through traditional methods. Its ability to provide targeted, effective pain relief with minimal invasiveness and temporary effects makes it an attractive option for many affected by chronic and acute pain conditions. As research and technology continues to advance, cryoneurolysis is likely to play an increasingly important role in the field of pain management (Bittman et al., 2019).

References

Biel, Emily et al. “The applications of cryoneurolysis for acute and chronic pain management.” Pain practice : the official journal of World Institute of Pain vol. 23,2 (2023): 204-215. doi:10.1111/papr.13182

Bittman, Ross W et al. “Interventional Cryoneurolysis: What Is the Same, What Is Different, What Is New?.” Seminars in interventional radiology vol. 36,5 (2019): 374-380. doi:10.1055/s-0039-1696705

Ilfeld, Brian M, and John J Finneran. “Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain.” Anesthesiology vol. 133,5 (2020): 1127-1149. doi:10.1097/ALN.0000000000003532

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Post-Anesthesia Exam

Post-Anesthesia Exam

The administration of anesthesia is a critical component of modern surgery, allowing for pain-free and stress-free procedures. However, the period immediately following anesthesia, known as the post-anesthesia period, is equally important for ensuring patient safety and a smooth recovery. During this period, the post-anesthesia exam is a comprehensive evaluation conducted by healthcare providers to monitor and manage an important part of monitoring patients and managing any potential complications arising from anesthesia.

The post-anesthesia exam is essential for several reasons. First, anesthesia, while generally safe, can lead to complications such as respiratory issues, cardiovascular instability, and adverse reactions to medications. Early detection through a thorough post-anesthesia exam can prevent issues from escalating. Second, assessing and managing postoperative pain is crucial for patient comfort and recovery. The exam helps tailor pain relief measures to the individual needs of each patient. Third, evaluating the patient’s return to baseline cognitive and motor functions ensures that they are recovering appropriately from the effects of anesthesia. Finally, identifying and treating symptoms of nausea and vomiting can prevent further complications and improve patient comfort ^1,2. Standardizing the post-anesthesia exam is an important goal for improving quality of care ³.

The post-anesthesia exam is comprehensive and covers various aspects of the patient’s recovery. Continuous monitoring of vital signs, including heart rate, blood pressure, respiratory rate, and oxygen saturation, is critical. It helps detect any deviations from normal ranges that may indicate complications. A neurological assessment also includes checking the patient’s level of consciousness, orientation, and ability to follow commands. Assessing neurological function is vital to ensure that the patient is emerging from anesthesia without any adverse effects. In addition, ensuring that the patient has a clear airway and is breathing adequately is paramount. The exam includes listening to breath sounds, checking for adequate chest rise, and monitoring for any signs of respiratory distress. In parallel, evaluating the heart’s function includes checking for abnormal rhythms, signs of fluid overload or dehydration, and ensuring stable blood pressure and heart rate.

Using pain scales, healthcare providers determine the level of pain the patient is experiencing and administer appropriate analgesics. Effective pain management is essential for patient comfort and recovery. Healthcare providers also assess for symptoms of nausea and vomiting and provide antiemetic medications as needed to ensure patient comfort. Finally, the team checks the surgical site for excessive bleeding, swelling, or signs of infection. Ensuring proper wound care can prevent postoperative complications. The team also monitors fluid intake and output and checks electrolyte levels, ensuring that the patient maintains proper hydration and metabolic balance ^1,4.

Most patients will have stable vital signs, indicating a smooth recovery. Minor fluctuations are normal, but significant deviations necessitate immediate attention. It is common, however, for patients to experience mild disorientation or grogginess, which usually resolves within a few hours. Ensuring a calm and supportive environment aids in this recovery. Patients may also frequently report a certain degree of pain or discomfort. Effective pain management strategies, including medications and non-pharmacological methods, are leveraged to address this. Nausea is a common finding and can be managed with antiemetics. Ensuring that patients remain in a semi-upright position can also help alleviate symptoms ^5–7.

The post-anesthesia exam is a critical step in the surgical care continuum, ensuring that patients recover safely and comfortably from anesthesia. By thoroughly assessing vital signs, neurological status, respiratory and cardiovascular functions, pain levels, and the surgical site, healthcare providers can detect and manage any complications promptly.

References

1. Nursing guidelines : Routine post anaesthetic observation. Available at: https://www.rch.org.au/rchcpg/hospital_clinical_guideline_index/Routine_post_anaesthetic_observation/. (Accessed: 20th June 2024)

2. Litwack, K. Post-anesthesia assessment: what medical-surgical nurses need to know. Medsurg Nurs. (1993).

3. Zemedkun, A. et al. Assessment of postoperative patient handover practice and safety at post anesthesia care unit of Dilla University Referral Hospital, Ethiopia: A cross-sectional study. Ann. Med. Surg. (2022). doi:10.1016/j.amsu.2022.103915

4. How to Assess the Post-operative Surgical Patient – OSCE Guide | Geeky Medics. Available at: https://geekymedics.com/how-to-assess-the-postoperative-surgical-patient-osce-guide/. (Accessed: 20th June 2024)

5. Abebe, B. et al. Incidence and factors associated with post-anesthesia care unit complications in resource-limited settings: An observational study. Heal. Sci. Reports (2022). doi:10.1002/hsr2.649

6. Street, M., Phillips, N. M., Kent, B., Colgan, S. & Mohebbi, M. Minimising post-operative risk using a Post-Anaesthetic Care Tool (PACT): Protocol for a prospective observational study and cost-effectiveness analysis. BMJ Open (2015). doi:10.1136/bmjopen-2014-007200

7. After Surgery: Discomforts and Complications | Johns Hopkins Medicine. Available at: https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/after-surgery-discomforts-and-complications. (Accessed: 20th June 2024

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Understanding and Mitigating Rebound Pain After Peripheral Nerve Blocks

Understanding and Mitigating Rebound Pain After Peripheral Nerve Blocks

Peripheral nerve blocks are a widely used technique for providing effective pain relief during and after surgical procedures. While they offer significant benefits, one common and challenging issue is rebound pain. This phenomenon occurs when the nerve block wears off, leading to a sudden and often intense resurgence of pain. Understanding rebound pain and implementing strategies to mitigate it is crucial for improving patient outcomes and satisfaction.

What is Rebound Pain?

Rebound pain is characterized by a sharp increase in pain intensity following the resolution of a peripheral nerve block. It typically occurs within 12 to 24 hours after the block wears off and can be more severe than the initial postoperative pain. This sudden pain surge can be distressing for patients and challenging for healthcare providers to manage.

Causes of Rebound Pain

Rebound pain is believed to result from several factors. The primary cause is the sudden withdrawal of the nerve block’s analgesic effect, which can lead to heightened sensitivity and a strong pain response. Additionally, the body’s natural inflammatory response to surgery continues unabated once the block wears off, contributing to the pain intensity.

Preoperative Strategies

Effective management of rebound pain begins with preoperative planning. Educating patients about the possibility of rebound pain and setting realistic expectations can help them prepare mentally and emotionally. Preoperative discussions should include pain management plans that extend beyond the duration of the nerve block.

Preemptive analgesia, involving the administration of pain medications before the onset of surgical pain, can also be beneficial. Nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, and gabapentinoids can be given preoperatively to reduce the severity of rebound pain.

Intraoperative Approaches

During surgery, multimodal analgesia should be employed to manage pain from different pathways. Combining regional anesthesia with systemic analgesics, such as opioids and non-opioid medications, can provide a more balanced and prolonged pain relief.

The choice of local anesthetic and its duration of action are critical factors. Longer-acting local anesthetics, such as bupivacaine or ropivacaine, can delay the onset of rebound pain, giving more time for other analgesic measures to take effect.

Postoperative Pain Management

A comprehensive postoperative pain management plan is essential to mitigate rebound pain. This plan should include:

Scheduled Analgesics: Regularly scheduled pain medications, including NSAIDs and acetaminophen, can provide consistent pain control and reduce the intensity of rebound pain.

Opioids: Short-term use of opioids may be necessary for managing severe rebound pain. However, their use should be carefully monitored to avoid dependency and side effects.

Adjuvant Therapies: Medications such as gabapentinoids, muscle relaxants, and corticosteroids can be used as adjuncts to enhance pain relief.

Rescue Analgesia: A plan for rescue analgesia should be in place for patients experiencing breakthrough pain. Rapid-acting opioids or additional doses of existing medications can help manage these pain episodes.

Non-Pharmacological Interventions

Non-pharmacological interventions can complement medical pain management strategies. Techniques such as ice packs, elevation, and physical therapy can help reduce pain and inflammation postoperatively. Additionally, mindfulness practices and relaxation techniques can aid in managing pain perception and reducing anxiety.

Patient Education and Follow-Up

Educating patients about the potential for rebound pain and the importance of adhering to the pain management plan is crucial. Providing clear instructions on medication schedules and non-pharmacological techniques empowers patients to manage their pain effectively.

Regular follow-up appointments allow healthcare providers to monitor pain levels and adjust the pain management plan as needed. Early intervention in cases of severe rebound pain can prevent complications and improve overall patient comfort.

Conclusion

Rebound pain after peripheral nerve blocks is a significant concern that requires a proactive and multifaceted approach. By understanding its causes and implementing comprehensive pain management strategies, healthcare providers can significantly reduce the impact of rebound pain on patients. Preoperative planning, intraoperative techniques, and postoperative care all play vital roles in mitigating this challenging condition.

Through patient education, careful monitoring, and the use of multimodal analgesia, the medical community can enhance the effectiveness of peripheral nerve blocks and improve postoperative recovery experiences. As research continues and new strategies are developed, the goal remains to provide optimal pain relief and enhance the quality of care for surgical patients.

Uncategorized

OR Temperature

The temperature of an operating room (OR) affects both patient outcomes and the efficiency of surgical procedures. Maintaining an optimal OR temperature is essential for ensuring patient safety, preventing complications, and providing a comfortable environment for the surgical team.

Operating room temperature is crucial for several reasons. First, it affects patient outcomes. Hypothermia is a significant risk during surgery, particularly for patients undergoing lengthy procedures or those with compromised health. Even mild hypothermia can lead to complications such as increased blood loss, infection rates, and extended hospital stays. Maintaining an appropriate OR temperature helps prevent these risks. Second, OR temperature impacts surgical efficiency. A comfortable OR temperature ensures that the perioperative team can perform at their best. Anesthesiologists, surgeons, and supporting providers must remain focused and dexterous, and an overly cold environment can impair fine motor skills and concentration. Finally, OR temperature impacts infection control. Temperature and humidity levels in the OR play a role in controlling the spread of airborne contaminants. Maintaining a balanced temperature helps ensure that the environment remains sterile and reduces the risk of postoperative infections ^1,2.

Several factors must be considered when setting and maintaining OR temperatures. Members of the perioperative team may wear multiple layers of sterile clothing, which can make a warmer OR uncomfortable and impair their performance. Additionally, different procedures may have varying requirements for temperature control. The health and age of the patient also influence temperature management, with infants, the elderly, and patients with compromised health requiring more careful temperature regulation to prevent hypothermia.

Typically, the ideal temperature range for an OR falls between 18 and 25°C, with some variation based on the type of surgery and the patient’s condition. The relative humidity, meanwhile, should be about 50%. For surgeries involving significant blood loss or prolonged duration, like cardiovascular and trauma surgery, a slightly higher temperature may be beneficial to help maintain patient body temperature. Since children are more susceptible to hypothermia, OR temperatures for pediatric surgical cases may be set slightly higher ^3,4.

Warming blankets or fluid warmers are often used to maintain patient temperature during lengthy or complex surgeries. In addition, modern ORs are equipped with sophisticated HVAC systems that allow precise control of temperature and humidity levels. The use of temperature monitoring devices on patients provides important information to the perioperative team ⁵.

Maintaining an optimal OR temperature is a delicate balance that requires consideration of patient safety, surgical efficiency, and infection control. By adhering to recommended temperature ranges and adjusting based on the specific needs of the surgery and the patient, healthcare providers can enhance surgical outcomes and ensure a safe, comfortable environment for both patients and providers.

References

1. Hakim, M. et al. The Effect of Operating Room Temperature on the Performance of Clinical and Cognitive Tasks. Pediatr. Qual. Saf. (2018). doi:10.1097/pq9.0000000000000069

2. Why Operating Rooms Are So Cold. Available at: https://www.verywellhealth.com/are-operating-rooms-cold-to-prevent-infection-2549274. (Accessed: 21st May 2024)

3. Operating Theatre Temperature & Humidity Guidelines – Cairn Technology. Available at: https://cairntechnology.com/operating-theatre-temperature-humidity-guidelines/. (Accessed: 21st May 2024)

4. ELLIS, F. P. THE CONTROL OF OPERATING-SUITE TEMPERATURES. Br. J. Ind. Med. (1963). doi:10.1136/oem.20.4.284

5. Broad to Precise Temperature Control for Industry – Air Innovations. Available at: https://airinnovations.com/environmental-control/broad-to-precise-temperature-control-for-industry/. (Accessed: 21st May 2024)

Uncategorized

Comparing Spinal vs. Epidural Anesthesia

Neuraxial anesthesia refers to the administration of local anesthesia around the central nervous system, specifically the spinal cord. Types of neuraxial anesthesia include spinal, epidural, and combined spinal-epidural techniques. The primary difference among these different anesthetic techniques is the anatomic location of injection. Epidural anesthesia is performed by introducing a needle between the lumbar, thoracic, or cervical vertebrae and injecting anesthetic medication into the epidural space, while spinal anesthesia involves administration of medications into the subarachnoid space. However, spinal and epidural anesthesia are applicable to many of the same surgical procedures.

Typically, neuraxial anesthesia is utilized for surgeries involving the lower abdomen and lower extremities. Spinal anesthesia is generally administered as a single injection, while epidural anesthesia is commonly delivered via a catheter for continuous infusion. The insertion of the spinal anesthesia needle is typically targeted at a mid- to low-lumbar intervertebral space, below the termination of the conus medullaris. In contrast, needle placement for an epidural injection can be performed at various locations along the distal end of the neuraxial canal. Catheter-based neuraxial anesthesia allows for prolonged anesthesia and the ability to adjust the onset of the anesthetic. Conversely, single-shot spinal or epidural anesthesia is limited to the duration of action of the administered drug.

Spinal and epidural techniques each have their own set of advantages and disadvantages. Common advantages of spinal anesthesia include: 1) rapid onset of block, 2) a technically easy procedure, 3) low required doses of local anesthetic and opioids, and 4) a reliably symmetric block. Disadvantages of spinal anesthesia include: 1) limited duration of action with single-shot injections, 2) limited ability to extend block, and 3) the requirement of dural puncture.

Advantages of epidural anesthesia include: 1) ability to easily prolong the duration and extent of the block, and 2) may be used for postoperative analgesia. Disadvantages of epidural anesthesia include: 1) relatively slow onset of anesthesia, 2) higher required doses of local anesthetic and opioids than spinal techniques, 3) risk of post-dural puncture headache with unintentional dural puncture, 4) possibility of patchy or asymmetric block, and 5) an unreliable sacral block.

A recent meta-analysis by Cochrane examined the efficacy and side-effects of spinal versus epidural anesthesia in women undergoing caesarean section. The analysis included ten randomized controlled trials. It found no significant differences between spinal and epidural techniques in terms of failure rate, need for additional intraoperative analgesia, conversion to general anesthesia, maternal satisfaction, need for postoperative pain relief, or neonatal intervention. However, although women who received spinal anesthesia had a shorter time from the start of the anesthetic to the start of the operation, they also had a higher likelihood of requiring treatment for hypotension. The authors concluded that both spinal and epidural techniques are effective for providing anesthesia during caesarean section. Still, due to the low incidence and/or lack of reporting, no definitive conclusions could be drawn regarding intraoperative side effects and postoperative complications.

Spinal and epidural anesthesia are two types of neuraxial anesthesia that primarily differ in terms of the anatomic location of local anesthetic administration. While each technique has its own advantages and disadvantages, they are both effective and relatively safe.

References

Practice Advisory for the Prevention, Diagnosis, and Management of Infectious Complications Associated with Neuraxial Techniques: An Updated Report by the American Society of Anesthesiologists Task Force on Infectious Complications Associated with Neuraxial Techniques and the American Society of Regional Anesthesia and Pain Medicine. Anesthesiology. 2017 Apr;126(4):585-601. doi: 10.1097/ALN.0000000000001521. PMID: 28114178.

Hebl JR, Horlocker TT, Kopp SL, Schroeder DR. Neuraxial blockade in patients with preexisting spinal stenosis, lumbar disk disease, or prior spine surgery: efficacy and neurologic complications. Anesth Analg. 2010 Dec;111(6):1511-9. doi: 10.1213/ANE.0b013e3181f71234. Epub 2010 Sep 22. PMID: 20861423.

Hebl JR, Horlocker TT, Schroeder DR. Neuraxial anesthesia and analgesia in patients with preexisting central nervous system disorders. Anesth Analg. 2006 Jul;103(1):223-8, table of contents. doi: 10.1213/01.ane.0000220896.56427.53. PMID: 16790657.

Hartmann B, Junger A, Klasen J, Benson M, Jost A, Banzhaf A, Hempelmann G. The incidence and risk factors for hypotension after spinal anesthesia induction: an analysis with automated data collection. Anesth Analg. 2002 Jun;94(6):1521-9, table of contents. doi: 10.1097/00000539-200206000-00027. PMID: 12032019.

Carpenter RL, Caplan RA, Brown DL, Stephenson C, Wu R. Incidence and risk factors for side effects of spinal anesthesia. Anesthesiology. 1992 Jun;76(6):906-16. doi: 10.1097/00000542-199206000-00006. PMID: 1599111.

Bonica JJ, Kennedy WF Jr, Ward RJ, Tolas AG. A comparison of the effects of high subarachnoid and epidural anesthesia. Acta Anaesthesiol Scand Suppl. 1966;23:429-37. doi: 10.1111/j.1399-6576.1966.tb01043.x. PMID: 6003651.

Ng K, Parsons J, Cyna AM, Middleton P. Spinal versus epidural anaesthesia for caesarean section. Cochrane Database Syst Rev. 2004;2004(2):CD003765. doi: 10.1002/14651858.CD003765.pub2. PMID: 15106218; PMCID: PMC8728877.