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Studies suggest that postoperative morbidity and mortality may be increased when neuraxial blockade is used either alone or in combination with general anesthesia.
Studies suggest that postoperative morbidity and mortality may be increased when neuraxial blockade is used either alone or in combination with general anesthesia.
False
Which of the following conditions may be reduced by neuraxial blocks?
Which of the following conditions may be reduced by neuraxial blocks?
What are the three layers of the meninges?
What are the three layers of the meninges?
Pia mater, arachnoid mater, dura mater
The epidural space is located within the subarachnoid space.
The epidural space is located within the subarachnoid space.
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The spinal cord normally extends from the foramen magnum to the level of L3 in adults.
The spinal cord normally extends from the foramen magnum to the level of L3 in adults.
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Where does the spinal cord end in children?
Where does the spinal cord end in children?
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The principal site of action for neuraxial blockade is believed to be the nerve root.
The principal site of action for neuraxial blockade is believed to be the nerve root.
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Spinal anesthesia involves injecting local anesthetic into the epidural space.
Spinal anesthesia involves injecting local anesthetic into the epidural space.
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Epidural and caudal anesthesia both involve injecting local anesthetic into the epidural space.
Epidural and caudal anesthesia both involve injecting local anesthetic into the epidural space.
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Spinal anesthesia requires a much larger dose and volume of local anesthetic compared to epidural anesthesia.
Spinal anesthesia requires a much larger dose and volume of local anesthetic compared to epidural anesthesia.
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What are the main indications for neuraxial blocks?
What are the main indications for neuraxial blocks?
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Neuraxial blocks can only be used alone, not in conjunction with general anesthesia.
Neuraxial blocks can only be used alone, not in conjunction with general anesthesia.
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Sensory blockade in neuraxial anesthesia interrupts both somatic and visceral painful stimuli.
Sensory blockade in neuraxial anesthesia interrupts both somatic and visceral painful stimuli.
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The phenomenon of differential blockade in neuraxial anesthesia is due to the fact that the size and character of the fiber types remain constant throughout the spinal cord.
The phenomenon of differential blockade in neuraxial anesthesia is due to the fact that the size and character of the fiber types remain constant throughout the spinal cord.
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Differential blockade typically results in sympathetic blockade that is more caudal than the sensory block.
Differential blockade typically results in sympathetic blockade that is more caudal than the sensory block.
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Neuraxial anesthesia blocks all autonomic transmission, including both sympathetic and parasympathetic.
Neuraxial anesthesia blocks all autonomic transmission, including both sympathetic and parasympathetic.
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What is the primary parasympathetic nerve that is not blocked by neuraxial anesthesia?
What is the primary parasympathetic nerve that is not blocked by neuraxial anesthesia?
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The physiological responses of neuraxial blockade primarily result from increased sympathetic tone.
The physiological responses of neuraxial blockade primarily result from increased sympathetic tone.
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Neuraxial blocks always result in a significant increase in blood pressure.
Neuraxial blocks always result in a significant increase in blood pressure.
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A high sympathetic block can block the sympathetic cardiac accelerator fibers, which arise at T1-T4.
A high sympathetic block can block the sympathetic cardiac accelerator fibers, which arise at T1-T4.
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What are the potential causes of profound hypotension during neuraxial blockade?
What are the potential causes of profound hypotension during neuraxial blockade?
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Unopposed vagal tone is believed to be a contributing factor to the sudden cardiac arrest sometimes seen with spinal anesthesia.
Unopposed vagal tone is believed to be a contributing factor to the sudden cardiac arrest sometimes seen with spinal anesthesia.
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What measures can be taken to minimize the degree of hypotension during neuraxial blockade?
What measures can be taken to minimize the degree of hypotension during neuraxial blockade?
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Volume loading with 10–20 mL/kg of intravenous fluid is always effective in preventing hypotension during neuraxial blockade.
Volume loading with 10–20 mL/kg of intravenous fluid is always effective in preventing hypotension during neuraxial blockade.
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Left uterine displacement in the third trimester of pregnancy does not have any effect on minimizing hypotension during neuraxial blockade.
Left uterine displacement in the third trimester of pregnancy does not have any effect on minimizing hypotension during neuraxial blockade.
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Excessive bradycardia should be treated with vasopressors, while hypotension should be treated with atropine.
Excessive bradycardia should be treated with vasopressors, while hypotension should be treated with atropine.
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Ephedrine is a vasopressor that has both direct and indirect beta-adrenergic effects, increasing heart rate and contractility, and causing vasoconstriction.
Ephedrine is a vasopressor that has both direct and indirect beta-adrenergic effects, increasing heart rate and contractility, and causing vasoconstriction.
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Surgical trauma does not cause a systemic neuroendocrine response.
Surgical trauma does not cause a systemic neuroendocrine response.
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What are the clinical manifestations of the systemic neuroendocrine response to surgical trauma?
What are the clinical manifestations of the systemic neuroendocrine response to surgical trauma?
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Neuraxial blockade can suppress the neuroendocrine stress response to surgical trauma.
Neuraxial blockade can suppress the neuroendocrine stress response to surgical trauma.
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Neuraxial block-induced sympathectomy results in a dilated, relaxed gut with reduced peristalsis.
Neuraxial block-induced sympathectomy results in a dilated, relaxed gut with reduced peristalsis.
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Postoperative epidural analgesia with local anesthetics and minimal systemic opioids can delay the return of gastrointestinal function.
Postoperative epidural analgesia with local anesthetics and minimal systemic opioids can delay the return of gastrointestinal function.
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Loss of autonomic bladder control during neuraxial blockade typically results in urinary retention.
Loss of autonomic bladder control during neuraxial blockade typically results in urinary retention.
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Placing a urinary catheter perioperatively eliminates the risk of urinary retention.
Placing a urinary catheter perioperatively eliminates the risk of urinary retention.
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What are the major contraindications to neuraxial anesthesia?
What are the major contraindications to neuraxial anesthesia?
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What are some relative contraindications to neuraxial anesthesia?
What are some relative contraindications to neuraxial anesthesia?
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Sepsis or bacteremia can increase the risk of spreading infectious agents into the epidural or subarachnoid space during neuraxial anesthesia.
Sepsis or bacteremia can increase the risk of spreading infectious agents into the epidural or subarachnoid space during neuraxial anesthesia.
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Patients with preexisting neurological deficits may experience worsening symptoms following neuraxial anesthesia.
Patients with preexisting neurological deficits may experience worsening symptoms following neuraxial anesthesia.
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Patients with dementia, psychosis, or emotional instability are generally not at an increased risk for complications during neuraxial anesthesia.
Patients with dementia, psychosis, or emotional instability are generally not at an increased risk for complications during neuraxial anesthesia.
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A normal prothrombin time (PT) and INR should be documented prior to neuraxial anesthesia in patients on oral anticoagulants.
A normal prothrombin time (PT) and INR should be documented prior to neuraxial anesthesia in patients on oral anticoagulants.
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Aspirin and other NSAIDs increase the risk of spinal hematoma during neuraxial anesthesia.
Aspirin and other NSAIDs increase the risk of spinal hematoma during neuraxial anesthesia.
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Neuraxial blockade should be avoided in patients on therapeutic doses of heparin, regardless of their partial thromboplastin time.
Neuraxial blockade should be avoided in patients on therapeutic doses of heparin, regardless of their partial thromboplastin time.
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Prophylactic "minidose" subcutaneous heparin is a contraindication to neuraxial anesthesia.
Prophylactic "minidose" subcutaneous heparin is a contraindication to neuraxial anesthesia.
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Neuraxial anesthesia is preferred 12 hours after the last dose of low-molecular-weight heparin (LMWH).
Neuraxial anesthesia is preferred 12 hours after the last dose of low-molecular-weight heparin (LMWH).
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Neuraxial blocks can be performed in any setting, including those with limited equipment and drugs.
Neuraxial blocks can be performed in any setting, including those with limited equipment and drugs.
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Standard monitoring should be avoided during neuraxial procedures.
Standard monitoring should be avoided during neuraxial procedures.
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Nonpharmacologic patient preparation is discouraged before neuraxial anesthesia.
Nonpharmacologic patient preparation is discouraged before neuraxial anesthesia.
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Supplemental oxygen is typically not needed for neuraxial procedures.
Supplemental oxygen is typically not needed for neuraxial procedures.
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Standard sterility is not essential for neuraxial blocks, as it is a minimally invasive procedure.
Standard sterility is not essential for neuraxial blocks, as it is a minimally invasive procedure.
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Spinous processes are rarely palpable and difficult to define the midline on the back.
Spinous processes are rarely palpable and difficult to define the midline on the back.
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The spinous process of T7 is generally at the same level as the inferior angle of the scapula.
The spinous process of T7 is generally at the same level as the inferior angle of the scapula.
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A line drawn between the highest points of both iliac crests usually crosses either the body of L4 or the L4-L5 interspace.
A line drawn between the highest points of both iliac crests usually crosses either the body of L4 or the L4-L5 interspace.
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The anatomic midline is typically easier to appreciate when the patient is in the lateral decubitus position, especially for very obese patients.
The anatomic midline is typically easier to appreciate when the patient is in the lateral decubitus position, especially for very obese patients.
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Flexion of the spine can help obscure the anatomical landmarks for neuraxial procedures.
Flexion of the spine can help obscure the anatomical landmarks for neuraxial procedures.
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The lateral decubitus position is rarely used for neuraxial procedures.
The lateral decubitus position is rarely used for neuraxial procedures.
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The Buie's (Jackknife) position is often used for upper abdominal procedures.
The Buie's (Jackknife) position is often used for upper abdominal procedures.
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The Buie's (Jackknife) position allows for easy confirmation of subarachnoid needle tip placement by free flow of CSF.
The Buie's (Jackknife) position allows for easy confirmation of subarachnoid needle tip placement by free flow of CSF.
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Spinal anesthetic solution directly affects nerve roots to inhibit conduction.
Spinal anesthetic solution directly affects nerve roots to inhibit conduction.
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The first "pop" sensation during spinal anesthesia is typically caused by penetration of the dura-arachnoid membrane.
The first "pop" sensation during spinal anesthesia is typically caused by penetration of the dura-arachnoid membrane.
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Successful dural puncture for spinal anesthesia is confirmed by withdrawing the stylet to verify free flow of CSF.
Successful dural puncture for spinal anesthesia is confirmed by withdrawing the stylet to verify free flow of CSF.
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All spinal needles should have a tightly fitting removable stylet that completely occludes the lumen during injection.
All spinal needles should have a tightly fitting removable stylet that completely occludes the lumen during injection.
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What are the two main types of spinal needles based on tip design?
What are the two main types of spinal needles based on tip design?
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Quincke needles are considered blunt tip (pencil-point) needles.
Quincke needles are considered blunt tip (pencil-point) needles.
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Blunt tip (pencil-point) needles are associated with a decreased incidence of postdural puncture headache, compared to sharp tip needles.
Blunt tip (pencil-point) needles are associated with a decreased incidence of postdural puncture headache, compared to sharp tip needles.
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The Whitacre needle is a side-injection needle with a long opening.
The Whitacre needle is a side-injection needle with a long opening.
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In general, larger gauge spinal needles are associated with a lower incidence of headache.
In general, larger gauge spinal needles are associated with a lower incidence of headache.
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The baricity of a spinal anesthetic solution refers to its density relative to blood.
The baricity of a spinal anesthetic solution refers to its density relative to blood.
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Hyperbaric solutions tend to move caudally in the supine position.
Hyperbaric solutions tend to move caudally in the supine position.
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If the patient remains in a lateral position, a hypobaric spinal solution will have a greater effect on the dependent side.
If the patient remains in a lateral position, a hypobaric spinal solution will have a greater effect on the dependent side.
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A "saddle block" is often achieved by keeping the patient sitting for 3-5 minutes following injection.
A "saddle block" is often achieved by keeping the patient sitting for 3-5 minutes following injection.
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The level of epidural anesthesia is generally more predictable than the level of spinal anesthesia.
The level of epidural anesthesia is generally more predictable than the level of spinal anesthesia.
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In adults, a dose of 1-2 mL of local anesthetic per segment is typically used to achieve a desired level of epidural block.
In adults, a dose of 1-2 mL of local anesthetic per segment is typically used to achieve a desired level of epidural block.
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Additives to the local anesthetic, especially opioids, tend to have a greater effect on the duration of epidural block than on its quality.
Additives to the local anesthetic, especially opioids, tend to have a greater effect on the duration of epidural block than on its quality.
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Chloroprocaine, lidocaine, and mepivacaine are examples of long-acting epidural anesthetic agents.
Chloroprocaine, lidocaine, and mepivacaine are examples of long-acting epidural anesthetic agents.
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Bupivacaine, levobupivacaine, and ropivacaine are examples of short-acting epidural anesthetic agents.
Bupivacaine, levobupivacaine, and ropivacaine are examples of short-acting epidural anesthetic agents.
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Only preservative-free local anesthetic solutions are used for epidural anesthesia.
Only preservative-free local anesthetic solutions are used for epidural anesthesia.
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Caudal anesthesia is a common neuraxial technique used in both adults and children.
Caudal anesthesia is a common neuraxial technique used in both adults and children.
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Caudal anesthesia is typically used for procedures above the diaphragm.
Caudal anesthesia is typically used for procedures above the diaphragm.
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The sacral hiatus is located above the coccyx and between two bony prominences called the sacral cornua.
The sacral hiatus is located above the coccyx and between two bony prominences called the sacral cornua.
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The standard epidural needle typically has a sharp tip for penetrating tissues.
The standard epidural needle typically has a sharp tip for penetrating tissues.
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The Tuohy needle is known for its sharp tip that helps penetrate the dura-arachnoid membrane easily.
The Tuohy needle is known for its sharp tip that helps penetrate the dura-arachnoid membrane easily.
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Placing a catheter into the epidural space allows for continuous infusion of anesthetic.
Placing a catheter into the epidural space allows for continuous infusion of anesthetic.
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Epidural catheters are primarily used for intraoperative epidural anesthesia.
Epidural catheters are primarily used for intraoperative epidural anesthesia.
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Epidural anesthesia is generally quicker in onset than spinal anesthesia but may be less dense in terms of the level of anesthetic block.
Epidural anesthesia is generally quicker in onset than spinal anesthesia but may be less dense in terms of the level of anesthetic block.
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Epidural anesthesia is frequently used to achieve motor block without analgesia.
Epidural anesthesia is frequently used to achieve motor block without analgesia.
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Toxic side effects from epidural anesthesia are unlikely if a full epidural dose is injected intrathecally.
Toxic side effects from epidural anesthesia are unlikely if a full epidural dose is injected intrathecally.
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Test doses are designed to detect both subarachnoid and intravascular injections during epidural anesthesia.
Test doses are designed to detect both subarachnoid and intravascular injections during epidural anesthesia.
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Aspirating before injection is sufficient to avoid intravenous injection during epidural anesthesia.
Aspirating before injection is sufficient to avoid intravenous injection during epidural anesthesia.
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Incremental dosing is considered less effective than test dosing in preventing complications during epidural anesthesia.
Incremental dosing is considered less effective than test dosing in preventing complications during epidural anesthesia.
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Study Notes
Neuraxial Anesthesia
- Studies suggest that postoperative morbidity and mortality may be reduced when neuraxial blockade is used alone or with general anesthesia.
- Neuraxial blocks may reduce complications such as venous thrombosis, pulmonary embolism, cardiac issues in high-risk patients, bleeding, transfusion requirements, vascular graft occlusion, pneumonia, and respiratory depression following upper abdominal or thoracic surgery in patients with chronic lung disease.
Spinal Column and Meninges
- The spinal column forms a double C shape, being convex anteriorly in the cervical and lumbar regions.
- The meninges consist of three layers: pia, arachnoid, and dura mater.
- Cerebrospinal fluid (CSF) is found between the pia and arachnoid mater in the subarachnoid space.
- The epidural space is a potential space within the spinal canal, bounded by the dura and the ligamentum flavum.
Spinal Cord Extent
- The spinal cord in adults extends from the foramen magnum to the level of L1.
- In children, the spinal cord ends at L3 and moves upward with age.
Neuraxial Blockade Mechanism
- The principal site of action for neuraxial blockade is the nerve root.
- Local anesthetic is injected into CSF (spinal anesthesia) or the epidural space (epidural and caudal anesthesia), blocking nerve roots in the subarachnoid or epidural space, respectively.
- Direct injection of local anesthetic into CSF for spinal anesthesia allows for a relatively small dose and volume to achieve dense sensory and motor blockade.
- The same local anesthetic concentration within nerve roots is achieved with much larger volumes during epidural and caudal anesthesia.
Indications for Neuraxial Blocks
- Neuraxial blocks may be used alone or in conjunction with general anesthesia for procedures below the neck.
- Neuraxial blocks are useful for lower abdominal, inguinal, urogenital, rectal, and lower extremity surgery.
- Lumbar spinal surgery can be performed under spinal anesthesia.
- Although upper abdominal procedures (like gastrectomy) have been performed with spinal or epidural anesthesia, these techniques aren't commonly used due to difficulty achieving a sufficient sensory level for patient comfort.
Types of Blocks: Somatic
- Sensory blockade generally affects both somatic and visceral pain stimuli.
- Differential blockade often leads to sympathetic blockade (influenced by temperature sensitivity) at a higher level than sensory (pain, light touch) blockade, which is in turn usually higher than motor blockade.
Types of Blocks: Autonomic
- Interruption of efferent autonomic transmission during neuraxial blocks results in sympathetic blockade.
- Sympathetic nerve fibers exit the spinal cord via spinal nerves from T1 to L2.
- Neuraxial anesthesia does not block the vagus nerve, the main parasympathetic supply.
- Physiological responses to neuraxial blockade result from decreased sympathetic tone and/or unopposed parasympathetic tone.
- Neuraxial blocks may cause variable decreases in blood pressure and heart rate.
- A high sympathetic block can prevent compensatory vasoconstriction and also block the sympathetic cardiac accelerator fibers that arise in T1-T4.
- Hypotension may result from arterial dilation, venous pooling, and bradycardia.
- Sudden cardiac arrest, sometimes seen during spinal anesthesia, might be related to unopposed vagal tone.
- Many factors (hydration, volume depletion, pregnancy) should be considered to minimize hypotension.
- Excessive or symptomatic bradycardia is treated with atropine; hypotension with vasopressors. Ephedrine increases heart rate/contractility and produces vasoconstriction.
- Surgical trauma can produce a systemic neuroendocrine response featuring increased ACTH, cortisol, epinephrine, norepinephrine, vasopressin, and renin-angiotensin-aldosterone system activation.
- Clinical manifestations can include intraoperative/postoperative hypertension, tachycardia, hyperglycemia, and altered renal function.
- Neuraxial blockade can partially or completely suppress the neuroendocrine stress response.
- Neuraxial blocks can lead to a small, contracted gut with active peristalsis.
- Postoperative epidural analgesia with local anesthetics and minimal systemic opioids can improve gastrointestinal function after open abdominal surgery.
- Autonomic blockade can cause urinary retention until the block wears off.
- If not using a urinary catheter, use the shortest duration regional anesthetic practical for the procedure and give the minimum safe volume of intravenous fluid.
Contraindications
- Major contraindications to neuraxial anesthesia include patient refusal, bleeding tendencies, severe hypovolemia, elevated intracranial pressure, and infection at the injection site.
- Other relative contraindications include severe valvular heart disease, sepsis and bacteremia (potentially spreading infectious agents into the epidural or subarachnoid space), and preexisting neurological deficits (which may worsen post-block).
- Patients with dementia, psychosis, or emotional instability may also be at risk.
Anticoagulants & Antiplatelets
- Documenting a normal prothrombin time (PT) and INR for oral anticoagulants (like Warfarin) is crucial before neuraxial blockade.
- Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) do not usually increase the risk of spinal hematoma.
- More potent antiplatelet agents (like Clopidogrel or Ticlopidine) should be discontinued, and neuraxial blockade administered only after the drug effects have fully worn off.
- For (Ticlid), that should be 14 days before the procedure.
- For (Plavix), that should be 7 days or more before the procedure.
- Prophylactic "minidose" subcutaneous heparin is not a contraindication to neuraxial anesthesia.
- Neuraxial anesthesia should be avoided in patients on therapeutic doses of heparin and with elevated partial thromboplastin time (PTT).
- For patients on LMWH, neuraxial anesthesia is preferable 12 hours after the last dose.
Technical Considerations
- Neuraxial blocks should only be performed in facilities prepared for intubation, resuscitation, and general anesthesia with readily available equipment and drugs.
- Standard monitoring should be implemented.
- Non-pharmacological patient preparation (explaining the procedure) can help minimize anxiety.
- Use supplemental oxygen with a face mask or nasal cannula as needed to prevent hypoxemia during sedation.
- Strict adherence to sterile techniques is essential.
Surface Anatomy
- Spinous processes are typically palpable and help define the midline.
- The most prominent cervical spinous process is C7.
- The spinous process of T7 is level with the inferior angle of the scapula.
- A line between the highest points of both iliac crests generally crosses the body of L4 or the L4-L5 interspace.
Patient Positioning
- Sitting: Anatomical midline is easier to establish in a sitting position, particularly with obese patients. Patients sit with elbows on thighs or the side of the bed, or resting on a pillow to maximize the "target" spinal area for the procedure.
- Lateral Decubitus: Many clinicians prefer a lateral position with knees flexed and pulled up towards the chest (fetal position). An assistant can be helpful in ensuring stable positioning.
- Buie's (Jackknife): This position is used for anorectal procedures. Patient positioning is the same as the surgical procedure (no moving between procedures). Disadvantage is that CSF flow might be impaired, so subarachnoid needle placement needs to be verified by aspirating CSF.
Spinal Anesthesia
- Spinal anesthetic solutions inhibit nerve conduction as they traverse the subarachnoid space.
- During procedure, the needle is advanced from the skin until two "pops" are felt during the procedure.
- The first pop signifies penetration of the ligamentum flavum, while the second signifies entry into the dura-arachnoid membrane.
- Penetration into the dura-arachnoid membrane is confirmed by verifying free flow of CSF after removing the stylet.
Spinal Needles
- Spinal needles come in various sizes, lengths, and designs (bevel/tip).
- All needles have a removable stylet that prevents tracking in the subarachnoid space.
- Needles are divided into sharp or blunt types (Quincke and pencil tip).
- Needle design selection (gauge and tip) can influence post-procedure headache risk.
Factors Influencing Spinal Block Level
- Local anesthetic solution baricity influences its migration in the CSF (higher density, higher cephalad migration).
- Patient position during and after injection influences the spread of the local anesthetic within the CSF (head-down to cephalad, lateral to non-dependent side).
- Drug dosage determines the cephalad level of anesthesia.
- Other factors such as weight, height, age, pregnancy, and injection site can also affect the spinal block level.
- Sitting position can result in "saddle-block" anesthesia, aiming for blocking nerves only in the lower lumbar and sacral regions.
Spinal Anesthetic Agents
- Preservative-free local anesthetic solutions are used.
- Adding vasoconstrictors (like epinephrine) and opioid analgesics can enhance and prolong the effects of spinal anesthesia.
- Hyperbaric bupivacaine and tetracaine are common agents with slower onset and prolonged duration.
- Lidocaine and procaine offer relatively rapid onset and shorter lasting effects.
Epidural Anesthesia
- Continuous epidural anesthesia is a broader application technique than typical single-dose spinal anesthesia.
- Epidural blocks can be performed at lumbar, thoracic, or cervical levels.
- Sacral epidural anesthesia is a caudal block.
- Indications include surgical anesthesia, obstetric analgesia, postoperative pain control, and chronic pain management.
- Epidural blocks can be single-shot or catheter-assisted with bolus or continuous infusions.
- Epidurals have a slower onset compared to spinal anesthesia and may not achieve as profound blockade.
Epidural Needle and Catheter
- Typical epidural needles are 17-18 gauge, approximately 3-3.5 inches long, with a blunt bevel and a gentle 15-30° curve at its tip (Tuohy needle).
- The blunt tip helps propel the needle through the ligamentum flavum without penetrating the dura mater during insertion.
- Catheters in the epidural space facilitate continuous infusion.
Toxic Epidural Effects and Mitigation
- Severe side effects are likely if a "full dose" of epidural anesthetic is administered intrathecally or intravascularly.
- Safeguards against these side effects include using test doses and administering the local anesthetic in increments.
- Test doses containing a local anesthetic and epinephrine are commonly used (to determine whether subarachnoid space was reached).
- Thorough aspiration before injection helps prevent intravenous injection.
- Incremental dosing is a strategy to prevent severe complications.
Factors Affecting Epidural Block Level
- Factors influence epidural anesthesia level less predictably than spinal anesthesia.
- Guidelines suggest 1-2 mL of local anesthetic per segment for adult patients. Achieving a particular level (such as T4 sensory) requires determining the correct volume of local anesthetic.
- Additives (particularly opioids) influence epidural anesthesia quality rather than duration.
Epidural Anesthetic Agents
- Common short- to medium-acting agents include chloroprocaine, lidocaine, and mepivacaine for surgical anesthesia.
- Longer-acting agents include bupivacaine, levobupivacaine, and ropivacaine.
- Preservative-free local anesthetics are essential.
Caudal Anesthesia
- Caudal anesthesia is the sacral portion of the epidural space.
- Popular in pediatric patients and anorectal surgery for adults.
- Often combined with general anesthesia (in children).
- Used for procedures below the diaphragm (urogenital, rectal, inguinal, lower extremity surgeries).
Sacral Hiatus
- The sacral hiatus can be located as a notch above the coccyx.
- It is between two bony prominences, the sacral cornua.
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Description
This quiz covers essential concepts related to neuraxial anesthesia, including its benefits in reducing postoperative complications. Additionally, it explores the anatomy of the spinal column and meninges, describing the spinal cord's extent and its protective layers.
