Anatomy

Question 1

The RCA supplies what distribution of the RV? What about SA node and AV node?

Answer 1

Anterior, lateral, inferior, and posterior, but the apex of the RV is supplied by LAD. SA and AV most of the time

Question 2

What does the RCA supply on the left side?

Answer 2

Posterior and inferior walls of the LV, posterior 1/3 of the IV septum, sometimes the apex of the LV, and portions of the right and left bundle branches.

Question 3

Why would occlusion in LAD NOT affect posterior base of the LV?

Answer 3

Because most blood from inferior and posterior LV is supplied by the PDA which arises from RCA 85% of time, or the LCX.

Question 4

What does the LAD supply?

Answer 4

Anterior LV, apex RV, usually apex LV, anterior 2/3 of RV septum

Question 5

What is promethazine?

Answer 5

A dopamine antagonist used for treating nausea.

Question 6

How to treat NAUSEA and vomiting from sympathetic block via neuraxial?

Answer 6

Atropinenoe gkucopyrolate because sometimes the nausea is from actual gut contraction and NOT hypotension. Look at what the question is asking you-is it asking you to treat hypotension or nausea related to the spinal?

Question 7

What exactly is ankylosis spondylitis? What HLA is it associated with? Is it associated with peripheral neuropathy? most extra-articulations joint issues are related to what?

Answer 7

It is an inflammatory disease of the axial spine. HLAB-27. It is NOT associated with peripheral neuropathy. Extra-articulations joint issues are related to the EYE, with uveitis being common.

Question 8

Why are people with Ankylosing spondylitis difficult to intimate, ventilate, and associated with spinal hematoma?

Answer 8

Decreased cervical spine ROM=difficult intubation
TMJ hypomobility=ill sealed faemask
Epidural hematoma-can happen with increased attempts due to ossification of ligaments

Question 9

The musculocutaneous nerve travels where, and innervated what? (Motor and sensory)

Answer 9

Travels in corachobrachialis muscle and innervates lateral forearm. It provides motor innervation to biceps brachii, coracobrachialis, and brachialis muscle.

Question 10

What two things are NOT in the axillary sheath?

Answer 10

No axillary vein or misculocutaneous nerve. The median, ulnar, and rdial neeves are in there as well as the axillary artery.

Question 11

What is the LCFN-where does it originate, and what sensation does it provide? Landmark for this block?

Answer 11

Branches from L2-L3 nerve roots, sensory innervation to anterolateral thigh. ASIS is a starting landmark-go 2.5 cm medial, ad 2.5 cm below

Question 12

Why are interscalene blocks so great for shoulder surgeries?

Answer 12

Because they block the entire plexus plus the suprascapikar nerve which supplies sensation to the shoulder.

Question 13

Brachial plexus is formed by what? And innervates what when it comes to the shoulder, but misses something else?

Answer 13

C5-T1, all motor and sensory innervation to the shoulder except the supraclavicukar nervevwhich supplies skin on shoulder.

Question 14

BP roots: ___, which give rise to

Answer 14

C5-T1

Give rise to three trunks (superior, middle, and inferior)-which emerge between the scalene muscles

Question 15

Why is IS block not recommended for hand surgery? Hoarseness after IS block?

Answer 15

Because it can miss the inferior trunk- Ulnar nerve

Hoarseness due to recurrent laryngeal nerve blockade

Question 16

What nerve is blocked by putting local in the palatoglossal fold?

Answer 16

Glossopharyngeal

Question 17

How is the recurrent laryngeal nerve blocker?

Answer 17

Transtracheal injection through the croci thyroid membrane.

Question 18

How is the superior laryngeal nerve blocked?

Answer 18

Injection at the horn of the hyoid bone or placing a pledger in the purified sinus.

Question 19

Explain SIME

Answer 19

Superior laryngeal nerve has 2 branches-sensation ABOVE the trachea is provided by the internal branch, and motor (to the cricothyroid) is provided by the external branch.

Question 20

Median nerve-sensation and motor:

Answer 20

Sensation in MEDIAL forearm, wrist flexion

Question 21

Radial nerve-sensation and motor

Answer 21

Sensation in dorsal hand, wrist extension

Question 22

what kind of block would you be doing if you touched Chassaignac’s tubercle? what does that even mean?

Answer 22

alpation of Chassaignac’s tubercle (the anterior tubercle of the transverse process of the C6 vertebra) which is located between the sternocleidomastoid muscle and the trachea

Question 23

common side effects of stellate ganglion block?

Answer 23

Common effects that are noted upon a successful stellate ganglion block are a result of the iatrogenic sympathectomy to the ipsilateral face. These include, but are not limited to: Horner’s syndrome (ptosis (A), miosis (B), and anhidrosis), injected conjunctiva (D), increased skin temperature (C), nasal congestion, and vasodilation

Question 24

signs of an epidural hematoma:

Answer 24

An epidural hematoma is associated with a dull aching back pain that is progressive and associated with progression of neurological symptoms. There is the progression of sensory loss followed by motor loss. Partial block resolution followed by block progression without bolus suggests hematoma. Diagnosis of an epidural hematoma is made with emergent MRI

Question 25

allergy to local anesthetics? which ones more commom?

methylparaben vs PABA:

Answer 25

True allergic events with local anesthetics are rare. The pH of injectate does not change the incidence of allergic reaction. Allergic reaction with ester type local anesthetics (e.g. procaine, benzocaine, tetracaine) most often occurs because of hypersensitivity to para-aminobenzoic acid (PABA). PABA a metabolite of ester local anesthetics. Allergic reaction to amide anesthetics is rarer than with esters and is likely a result of allergy to preservatives in solution. One preservative used for amide anesthetics is methylparaben, which can also be metabolized to PABA

Question 26

Bicarbonate-why would anyone add it to a solution?

Answer 26

Often bicarbonate is added to local anesthetic (often in a 1:10 ratio) to increase the pH of the solution. This increase of pH decreases pain on injection into peripheral tissues and also speeds the onset time of the local anesthetic by increasing the unionized portion of local anesthetic. Lidocaine remains relatively soluble in its unionized form. However ropivacaine and levobupivacaine are not, and therefore it is not recommended to have bicarbonate added for infusions. Recommendations for ropivacaine state that if bicarbonate is added the solution should be used within 5-10 minutes of mixing.

Question 27

where is the brachial plexus in relation to the subclavian artery?

Answer 27

The brachial plexus lies lateral, superior and posterior to the ScA.

Question 28

best possible practice to use to prevent PDPH (needle wise)

Answer 28

Use of the smallest possible (e.g. 27-gauge) non-cutting needle for spinal placement is likely the best practice to avoid PDPH. quincke over cutting

Question 29

T/F-aggressive hydration prevents PDPH

Answer 29

false-it does not PREVENT it

Question 30

which nerves supply the knee (sensory)?

Answer 30

femoral and sciatic

Question 31

Femoral nerve comes from? what does it provide sensation to?

Answer 31

The femoral nerve emerges from the lumbar plexus and is formed by L2-L4.Its anterior branch supplies sensation to the anterior and medial aspects of the thigh and further distal it gives rise to the saphenous nerve, which supplies the medial aspect of the leg below the knee-joint.

Question 32

Obturator nerve and LFCN-what do they supply?

Answer 32

The other major branches of the lumbar plexus are the genitofemoral, lateral femoral cutaneous, and obturator nerves. The obturator nerve gives innervation to the skin of the medial aspect of the thigh. In some patients, it gives innervation to a small area of the knee and the addition of this nerve block can sometimes help with intraoperative and postoperative analgesia. Because it innervates the medial thigh, blocking the obturator nerve can also help patients tolerate tourniquet pain. The lateral femoral cutaneous nerve provides sensation to the lateral aspect of the thigh above the knee. Although it does not provide sensation to the knee in most individuals, blockade of this nerve does help patients tolerate tourniquet pain during the procedure.

Question 33

sciatic nerve-where does it come from, what does it supply?

Answer 33

The sciatic nerve originates from the sacral plexus and is the combination of nerve roots L4-S3. It courses through the leg along the posterior thigh and then divides into the common peroneal and tibial nerves a little over halfway down the femur. The sciatic nerve and its branches supply sensation to the back of the thigh and knee as well as the entire lower leg, except for the medial portion which is supplied by the saphenous nerve

Question 34

what is Raynaud’s and how would a block affect it?

Answer 34

blood vessels constrict with cold or stress, so a block would relieve this

Question 35

risk factors for PDPH. does approach, or loss of resistance technique matter?

Answer 35

Other patient-related risk factors include history of previous PDPH (2.3 times more likely), history of air travel, and patients with a BMI < 30. Obese (BMI > 30) patients tend to be less susceptible to PDPH which is attributed to increased abdominal pressures which may reduce CSF leakage. Approach (midline vs. paramedian) and loss of resistance technique (air vs. saline for epidural placement) do not alter PDPH incidence.

Question 36

What does a lumbar plexus block block? what does it spare?

Answer 36

A LPB reliably blocks the femoral, lateral femoral cutaneous, and obturator nerves. It spares the sciatic nerve, though the commonly-used posterior approach for a LPB allows for easy access to the sciatic nerve for a separate block.
Sciatic is spared, so foot and ankle movements spared with LPB including, but not limited to the gastrocnemius, soleus, plantaris, and digital flexors) that allow plantar flexion at the ankle.

Question 37

obturator motor;

Answer 37

Hip adductionincluding the adductor longus, brevis, and magnus muscles)

Question 38

Femoral nerve motor

Answer 38

Blockade of the femoral nerve will prevent hip flexion (as it innervates the iliopsoas and quadriceps femoris muscles) and extension of the lower leg at the knee (quadriceps femoris muscles)

Question 39

Does the site of IV affect the Bier block?

Answer 39

the site of IV placement and injection does not affect the block efficacy

Question 40

How does a bier block work?

Answer 40

A Bier block provides extremity anesthesia by diffusion of local anesthetic from the veins into the capillaries and vasa nervosa surrounding the peripheral nerves. Local anesthetic also diffuses extravascularly into the nerves supplying the skin. Ischemia caused by the tourniquet also causes a degree of anesthesia by impairing nerve conduction.

Question 41

V2 of trigeminal nerve covers which things?

Answer 41

The sphenopalatine ganglion derives the bulk of its innervation from the maxillary branch (V2) of the trigeminal nerve and provides innervation to the nasal cavity mucosa, hard palate, and lacrimal gland.The infraorbital nerve is also derived from the maxillary branch of the trigeminal nerve, but it is mainly responsible for innervation of the lateral aspect of the skin overlying the nose, cheek, and upper lip

Question 42

What makes up femoral triangle? whats inside the femoral triangle?

Answer 42

The femoral triangle includes the femoral nerve, femoral artery, femoral vein, lymphatics, and pubic symphysis. The adductor longus muscle makes the medial aspect of the triangle and the inguinal ligament comprises the superior border of the triangle.The sartorius muscle creates the lateral border of the triangle

Question 43

Twitch monitor and femoral nerve block:

Answer 43

When a twitch monitor is used during a femoral nerve block, the quadriceps femoris is likely to contract with subsequent twitching of the patella - this is regarded to be adequate stimulation correlating to appropriate femoral nerve block

Question 44

What is TNS? Risk factors?

Answer 44

Transient neurologic syndrome can occur following spinal anesthesia and is defined as back pain with radiation of pain to the buttocks, thighs, hips, and calves, occurring within 24 hours after recovery from an otherwise uneventful spinal anesthetic. These symptoms typically last 1-3 days but neurophysiologic evaluation fails to show pathologic findings. Symptoms usually resolve spontaneously without further intervention.

The only factors found to be associated with increased risk of TNS are lidocaine spinal anesthesia, the lithotomy position, and ambulatory surgery with early ambulation. Pooling and maldistribution of hyperbaric local anesthetic encountered with the use of pencil-point spinal needles or spinal microcatheters are suggested to have a causative effect for neurological injury (cauda equina syndrome), but not TNS. Baricity of local anesthetics is not associated with the development of TNS following spinal anesthesia.

Question 45

twitch monitor stuff-which current do you want to use?

Answer 45

Since the charge (Q) required to cause depolarization is inversely proportional to the square of the distance (r) between the needle and the nerve (Q α 1/r2), the ability to elicit the desired response (e.g. twitch) at a very low current indicates the needle is very close to the nerve. Accordingly, a block has a high success rate when the desired response is elicited with a stimulating current of 0.4-0.5 mA. However, if the response occurs with a current < 0.3 mA, the needle may be intraneural which may increase the risk for block complications without necessarily increasing the block success rate.

Question 46

twitch monitor-connecting to red vs black-

Answer 46

Connecting the cathode lead (black, current flows from the cathode) of the nerve stimulator to the needle allows the desired response to be achieved using a lower (1/4 to 1/3) current than if the anode lead (red, current flows towards the anode) were connected to the needle. This is the standard against which the desired 0.4-0.5 mA current was determined. Accordingly, if the leads were accidentally switched (anode attached to needle), when a response is still elicited at 0.4 mA, this likely indicates that the needle is intraneural instead of just outside the nerve. This phenomenon occurs because a cathode needle “injects” current and causes nerve depolarization whereas stimulation with an anode needle leads to hyperpolarization.

Question 47

twitch monitor stiff-sine vs square wave, and insukated vs uninsukated needle?

Answer 47

you want to use square, and an insulated needle only disperses current from its tip and with a greater current density relative to an uninsulated needle

Question 48

Intercostobrachial nerve-when would you block it? It comes from what?

Answer 48

The intercostobrachial nerve supplies sensory innervation to the inner aspect of the upper arm. It may be anesthetized to prevent tourniquet-induced pain of the medial upper arm following otherwise adequate regional anesthesia to the upper extremity.comes from T2 and T1

Question 49

TAP block nerves blocked:

Answer 49

The nerves affected by transversus abdominis plane block include the intercostal, subcostal, ilioinguinal, and iliohypogastric nerves.

Question 50

peribulbar vs retrobulba blocks. what doees retrobulbar not block?

Answer 50

Peribulbar blocks are associated with a lower incidence of complications like retrobulbar hematoma. The decrease in complications, like retrobulbar hematoma and globe puncture, is the reason why peribulbar blocks may be preferred over retrobulbar blocks. Peribulbar block uses more local anesthetic. peribulbar can have chemosis. peribulbar happens farther back.

The retrobulbar block does not block the orbicularis oculi or levator palpebrae muscle. Therefore, an additional injection to block the facial nerve is required, such as the Van Lint block. The retrobulbar block is associated with a lower incidence of chemosis. retrobilbar has a higher incidence of hematoma

Question 51

oculocardiac reflex: what branches?

Answer 51

The oculocardiac reflex may be provoked during ophthalmic surgery. The afferent limb of the oculocardiac reflex is the trigeminal nerve, ophthalmic branch (CN V1), via the ciliary ganglion. The efferent limb is the vagus nerve (CN X), where pressure or traction on the eye can lead to bradycardia and even asystole. The reflex is more common in young individuals and during strabismus surgery.

Question 52

Sural nerve is a branch of:

Answer 52

branch of sciatic-covers lateral leg and thigh

Question 53

Which nerves are blocked i the ankle block? which other 2 blocks can combine to do the same thing?

Answer 53

To provide complete anesthesia/analgesia, all five nerves to the foot must be blocked: posterior tibial, common peroneal, deep peroneal, sural, and saphenous nerves. Alternatively, the sciatic (popliteal fossa) block and the saphenous nerve block may provide the same distribution of neural blockade.

Question 54

What is the McConell sign on TEE?

Answer 54

TEE can be suggestive of PE by the presence of regional wall motion abnormalities sparing the right ventricular apex (McConnell sign).

Question 55

Aortic aneurysm vs dissection on imaging:

Answer 55

Aortic aneurysm would show a dilated aorta and would not show an intimal flap dissecting the aorta

Question 56

when using a nerve stimulator for ISB, what do you want to see twitch?

Answer 56

When using a nerve stimulator, the desired motor response is twitching of the pectoralis, deltoid, arm, forearm, or hand muscles.

Question 57

If you get a diaphragmatic response when doing ISB, where does needle need to move?

Answer 57

Diaphragmatic stimulation during ISB using a nerve stimulator indicates phrenic nerve stimulation. The needle should be redirected posteriorly to achieve the desired nerve blockade

Question 58

twitches expected in femoral block, if the sartorius alone twitches, what should you do?

Answer 58

The end-point of a femoral nerve stimulation should be a patellar twitch, which on occasion may be accompanied by a sartorius twitch and would still be acceptable. However, if a sartorius twitch without patellar twitch is elicited, the needle should be redirected deeper and lateral.

Question 59

If epidural fragment is retained, what are you going to do about it (imaging wise), and what about what you’ll actually do?

Answer 59

The diagnostic test of choice for a retained epidural catheter fragment is computed tomography. Minor fragments may be left in place if they do not cause symptoms. Neurosurgical consultation should be considered for any symptomatic retained fragment or any fragment within the spinal canal.

Question 60

TEE imaging: is RV anterior? where is the non-coronary cusp located? Look at photo.

Answer 60

Right ventricle is an anterior structure, as is the right coronary cusp. The non-coronary cusp is always located next to the inter-atrial septum.
okay

Question 61

Foot eversion and dorsiflexion? is controlled by which nerve?

Answer 61

Foot eversion is controlled by peroneal nerve.

Question 62

Landmarks of popliteal block (posterior approach)

Answer 62

The landmarks for this approach are the biceps femoris laterally, semimembranosus medially, and the two heads of the gastrocnemius inferiorly.

Question 63

Twitch of the tibial nerve results in:

Answer 63

tibial nerve results in plantarflexion and inversion of the foot

Question 64

Tell me about the lateral popliteal nerve approach.

Answer 64

A second approach to the sciatic nerve is the lateral popliteal approach with the patient supine and the knee flexed to 90 degrees. A spot 7-8 cm (depending on the source) cephalad to the lateral epicondyle of the femur is located in a groove between the vastus lateralis and biceps femoris muscle. A needle is inserted at 90 degrees to the long axis of the leg until the femur is contacted. The needle is redirected posterior until a tibial nerve twitch is noted. During needle advancement the biceps femoris muscle will twitch and serves as a marker for nerve depth. The nerve should be within 2 cm of the cessation of the biceps femoris twitch, if not, no further needle advancement should commence given the medially located popliteal vessels and slight redirection of the needle posterior is needed. If a vastus lateralis muscle twitch is observed then the needle needs to be redirected posterior as the vastus lateralis muscle is the anterior anatomic landmark in the performance of this block. The success and distribution of blockade between the two techniques is similar.

Question 65

How does spinal anesthesia result in hypotension?

Answer 65

Spinal anesthesia causes a sympathectomy that often results in hypotension via three main mechanisms: arterial dilation (decreased afterload), venodilation (decreased preload), and bradycardia (parasympathetic dominance and/or the Bezold-Jarisch reflex).

Question 66

What is an elevated fractional area change?

Answer 66

An elevated fractional area change correlates with an above normal ejection fraction and increased cardiac output, which is not associated with spinal anesthesia.

Question 67

What is the Bezold-Jarisch reflex? How does it differ from the carotid baroreceptor reflex?

Answer 67

This parasympathetic-mediated reflex occurs when stretch receptors located mainly in the left ventricle respond to an acute decrease in left ventricular preload. The result is bradycardia and reduced contractility (and resultant hypotension). This reflex is thought to occur to allow the ventricle additional time to fill and increase preload. Normally, the carotid sinus baroreceptor response to hypotension (increased heart rate and contractility) dominates, but in the setting of an acute drop in ventricular preload (e.g. spinal anesthetic or nitrate use), the Bezold-Jarisch reflex may occur before the carotid sinus reflex.

Question 68

Explain manual in-line stabilization:

Minimal manipulation of:

Answer 68

This technique is accomplished by having two operators maintain the head, neck, and shoulders in a neutral position while the laryngoscopist intubates the tracheaThe first operator stabilizes the head and neck in a neutral position by grasping the mastoid processes with their fingertips and cradling the occiput with the palms of their hands. The second operator stabilizes both shoulders by holding them against the OR table, bed, or stretcher.
Minimal manipulation of mid cervical spine

Question 69

Cervical spine injury can be cleared once ALL of which things are met?

Answer 69

1. No midline cervical tenderness 2. No focal neurological deficit 3. Normally alert 4. Not intoxicated 5. No distracting painful injury.

Question 70

What is the most appropriate test to differentiate between cSF and saline? Why/

Answer 70

A point of care glucose test strip is the most appropriate test to differentiate cerebral spinal fluid from normal saline. The reliability and speed of the point of care glucose strip make it the most appropriate test for differentiating dural puncture from loss-of-resistance saline return.

Question 71

Nerve thing in photo

Answer 71

(Starting from medial) Men, underestimate, real

Question 72

Which nerves are blocked by axillary block? What is an axillary block good for? What nerve is usually missed in an axillary block?

Answer 72

Axillary nerve blocks provide excellent analgesia to structures of the upper extremity that lie distal to the elbow. Axillary block covers radial, median, and ulnar nerve. Musculocutaneous nerve is usually missed.

Question 73

What are the landmarks for an infra-gluteal sciatic nerve block?

Answer 73

ischial tuberosity, greater trochanter of the femur, and sciatic groove

Question 74

Sciatic nerve block photo:

Answer 74

Okay

Question 75

Achondroplasia and airway-what are you concerned with?

Answer 75

When planning for airway management in a patient with achondroplasia, atlantoaxial instability is the greatest concern.

Question 76

Sensation to the eye is provided by the ophthalmic nerve via _____.
Do you also have to block the facial nerve-why or why not?

Answer 76

long and short posterior ciliary nerves.
Since the orbicularis oculi muscle is innervated by the facial nerve, this results in the potential for eye movement during surgery unless that is blocked separately

Question 77

Five and dime reflex:

Answer 77

Oculocardiac reflex: “five and dime” reflex – it starts in the fifth cranial nerve (trigeminal) and exits the tenth cranial nerve (vagus)

Question 78

The obturator block is performed by injecting local anesthetic between ____ or ___

Answer 78

between the adductor longus and brevis muscles.
OR
between the adductor brevis and adductor magnus muscles-if you do the second, that will take away motor-which you don’t want

Question 79

P2 valve is most likely to become ischemic due to

Answer 79

single vessel blood supply

Question 80

The mnemonic ALABAMa is used to remember

Answer 80

muscles from superficial to deep: Adductor Longus, Adductor Brevis, Adductor Magnus.

Question 81

Obturator sensory vs motor:

Answer 81

anterio-sensory and motor

posterior-motor alone

Question 82

What does the median nerve supply (motor and sensory)? If it was missed in an axillary block, then where can it be blocked?

Answer 82

The sensory distribution of the median nerve is in the palm of the hand and its motor distribution provides flexion of the wrist. If the median nerve is missed, it can be blocked either at the level of the elbow or the wrist. At the elbow, the median nerve lies medial to the brachial artery in the antecubital fossa. The block is performed by inserting the needle just medial to the brachial pulse and can be performed with the aid of ultrasound, nerve stimulator, or paresthesias. At the wrist, the median nerve is located just lateral to the palmaris longus. A supplemental block can be performed at either of these sites, but since this patient is having wrist surgery, blocking the nerve at the elbow makes the most sense.

Question 83

What does sux do to LES tone? What about cricioid pressure? When is cricoid pressure contraindicated?

Answer 83

Sux increases LES tone,
Cricoid pressure decreases LES tone
Cricoid pressure is contraindicated with cervical spine and laryngeal fracture as well as active vomiting as the risk of esophageal rupture is increased.

Question 84

Complete vs partial bilateral nerve injury

What does the RLN supply?

Answer 84

Complete:
Complete bilateral RLN injury results in the vocal cords being in a paramedian position causing aphonia and aspiration risk (both abduction and adduction affected)
Partial:
Thus, partial bilateral recurrent laryngeal nerve injury results in complete obstruction (abductors affected most, unopposed adduction of vocal cords) and is an airway emergency.

The RLN provides the only abductors of the vocal cords which are very sensitive to injury/compression

Question 85

Central retinal artery occlusion. Is it painful?

Answer 85

Usually painless.

Question 86

Most common significant complication following retrobulbar blockade?
Explain oculocardiac reflex-are there long term sequelae?
Central retinal artery occlusion leads to:
Puncture of globe leads to:

Answer 86

Retrobulbar hemorrhage is the most common significant complication following retrobulbar blockade leading to an increase in intraocular pressure and vision loss. The oculocardiac reflex stimulation (more common than retrobulbar hemorrhage) may lead to bradycardia and heart block but rarely has significant long-term sequelae. Central retinal artery occlusion leads to painless vision loss, while puncture of the posterior globe leads to painful vision loss without an increase in intraocular pressure.C

Question 87

Obturator nerve originates from:

Would you ever need to additionally block the nerve?

Answer 87

L2-L4

Transurethral surgery of the bladder usually can be performed with spinal anesthesia without further consideration. If the tumor is along the lateral aspect of the bladder then the obturator nerve may be stimulated and the jerk reflex initiated even under spinal anesthesia. An obturator nerve block should be performed to help prevent this. Alternatively, general anesthesia with muscle relaxation can also be performed to prevent the reflex. If neuromuscular blocking agents are not used during general anesthesia, the obturator nerve block will still need to be performed.

Question 88

The muscle affected is the only vocal cord tensor and the patient is told that his speech will remain changed. Which of the nerves was most likely damaged in this patient?

Answer 88

The only vocal cord tensor is the cricothyroid muscle which is innervated by the external branch of the superior laryngeal nerve

Question 89

Features of a subdural block:

Is it something about the patient?

Answer 89

Several features - variable motor blockade, excessive sensory blockade, and sympatholysis out of proportion to anesthetic dose given, ‘classically’ define subdural block
Slow onset of blockade, restricted or unilateral distribution of the blockade, severe pain with injection, and even lack of cardiovascular depression can also be seen.Patients that have experienced a subdural block in the past appear to have a higher incidence of it reoccurring, and these patients may prove to be more difficult for neuraxial placement.

Question 90

Before considering giving naloxone in a patient who is not super awake, consider:

Answer 90

When they last got opioids, and their pupil size.

Question 91

What is tension pneumocephalus, what can be an offending agent?

Answer 91

Nitrous oxide should be avoided in patients with recent craniotomy procedures (generally 2-3 weeks). Nitrous oxide may result in expansion of pneumocephalus and result in tension pneumocephalus. Initial treatment supportive and includes high flow oxygen.Tension pneumocephalus may present as delayed awakening or altered level of consciousness, generalized convulsions, seizures, hypertension with resultant bradycardia, severe restlessness, or change in motor exam. Definitive treatment is aspiration of the air loculi by a neurosurgeon.

Question 92

Oculocardiac reflex -explain it,and how do you treat it?

Answer 92

The afferent limb of the oculocardiac reflex is via the trigeminal nerve (cranial nerve V), primarily via the ophthalmic division (V1). The efferent limb is via the vagus nerve (cranial nerve X), which then synapses on the sinoatrial node of the heart.

During ophthalmic surgery, the first line of treatment for bradycardia is to discontinue manipulation of the eye until the heart rate returns to baseline. Prophylactic antimuscarinics (e.g. atropine, glycopyrrolate) are not typically beneficial for adult patients.

Question 93

Sensation in lateral forearm innerated by:

Answer 93

musculocutaneous