Local anesthesia for a complex lower lip laceration (Mental nerve block)

A 20-year-old male kick boxer sustains a lower lip laceration during a practice match. The wound is complex and crosses the vermilion border. Which is the best way to achieve anesthesia?

• (A) Local infiltration with 1 percent lidocaine
• (B) Local infiltration with 1 percent lidocaine with epinephrine
• (C) Inferior alveolar nerve block
• (D) Lingular nerve block
• (E) Mental nerve block

answer is E. 

A regional block is preferred for a complex lower lip laceration because it preserves tissue planes and landmarks, facilitating anatomically correct repair. 
The mental nerve supplies the skin and mucus membranes of the lower lip. The mental foramen is located inside the lower lip at its junction with the lower gum, just posterior to the first premolar tooth.

To avoid nerve injury, 1 percent lidocaine with epinephrine is injected close to, but not into, the mental foramen. The inferior alveolar and lingular nerves do not supply the lower lip and thus would not be effective in this patient.

Ultrasound Guided Femoral Nerve Block for Large Thigh Laceration

Here is a quick case study on ultrasound guided regional anesthesia from the Emergency Ultrasound Nerve Block Project.

Why cricothyrotomy is the best site for emergency airway

You witness a choking incident in a restaurant. The Heimlich maneuver is unsuccessful at removing the food from the pharynx. The victim is having extreme difficulty breathing and starts to pass out. Where are you most likely to produce an emergency airway?

• a.In the midline just superior to the hyoid bone
• b.In the midline just inferior to the hyoid bone
• c.At the laryngeal notch
• d.At the junction between the thyroid cartilage and cricoid cartilage
• e.At tracheal ring 2 to 3 below the cricoid cartilage

The answer is (d).

The food is most likely stuck in the laryngeal pharynx, so you must produce an alternative airway below the glottis, which reflexly closes.
Locations around the hyoid bone (answers a and b)and above the laryngeal notch (answer c)are above the blockage and would not get air into the lungs. The isthmus of the thyroid gland
generally lies in front of the second and third tracheal ring (answer e), and because it is so highly vascular, it is not an ideal location for an emergency airway.

An additional alternative location for an emergency airway would be the jugular notch, but is not preferred because of the occurrence of a thyroid ima artery below the isthmus, in a small percentage of the population.

More useful links :

TRACHEOSTOMY,How to do!!

Clinical Complications of Tracheostomy

Mnemonic for Malignant hyperthermia treatment

Malignant hyperthermia or malignant hyperpyrexia is a rare life-threatening condition that is usually triggered by exposure to certain drugs used for general anesthesia in the operating room or also occur within the first few hours of recovery from anesthesia; specifically, the volatile anesthetic agents and the neuromuscular blocking agent, succinylcholine.

The syndrome is though to be due to a reduction in the reuptake of calcium by the sarcoplasmic reticulum necessary for termination of muscle contraction. Consequently, muscle contraction is sustained, resulting in signs of hypermetabolism, including acidosis, tachycardia, hypercarbia, glycolisis, hypoxemia, and heat production (hyperthermia).

Remember

"Some Hot Dude Better Give Iced Fluids Fast!"

(Hot dude = hypothermia):

Stop triggering agents
Hyperventilate/ Hundred percent oxygen
Dantrolene (2.5mg/kg)
Bicarbonate
Glucose and insulin
IV Fluids and cooling blanket
Fluid output monitoring/ Furosemide/ Fast heart [tachycardia]

The Supraclavicular Block

Indirect IA (Inferior Alveolar) nerve block on a model

University of The Pacific Arthur A. Dugoni School of Dentistry present a video illustrating the technique of Inferior Alveolar Nerve Block on a model by Dr. Anders Nattestad, Professor and Director, Department of Oral and Maxillofacial Surgery.

Causes of poor bilateral breath sounds after intubation

Think about DOPE

Endotracheal intubation: diagnosis of poor bilateral breath sounds after intubation

1. Displaced (usually right mainstem, pyreform fossa, etc.)
2. Obstruction (kinked or bitten tube, mucuous plug, etc.)
3. Pneumothorax (collapsed lung)
4. Esophagus

Umbilical vein catheterization technique

Umbilical vein catheterization may be a life-saving procedure in neonates who require vascular access and resuscitation. The umbilical vein remains patent and viable for cannulation until approximately 1 week after birth.
Umbilical vein catheters (UVC), are used for exchange transfusions, monitoring of central venous pressure, and infusion of fluids (when passed through the ductus venosus and near the right atrium); and for emergency vascular access for infusions of fluid, blood products or medications.
Usually in the emergency department peripheral access is preferred for critically ill newborns and if this is impossible, umbilical vein catheterization may be attempted.

Technique :

# The umbilical cord stump and surrounding abdomen should be sterilized with a bactericidal solution. Sterile drapes should be placed.
# A purse-string suture or umbilical tape is tied around the base of the stump to provide hemostasis and to anchor the line after the procedure.

# Using the scalpel, the cord is cut horizontally, approximately 1.5-2 cm from the abdominal wall. Two thick-walled small arteries and one thin-walled larger vein should be identified. The umbilical vein may continue to ooze blood.
# Hemostasis is achieved through tightening the umbilical tape or suture. The arteries do not usually bleed secondary to vasospasm.
# Forceps are then used to clear any thrombi and dilate the vein.
# A 3.5F catheter is used for preterm newborns, and a 5F catheter is used for full-term newborns.

5F umbilical catheter. Note proximal attachment for stopcock

# The catheter should be flushed with pre-heparinized solution and attached to a closed stopcock.
# The catheter is then grasped 1 cm from its distal tip with the iris forceps and gently inserted, aiming the tip toward the right shoulder. Advance the catheter only 1-2 cm beyond the point at which good blood return is obtained. This is approximately 4-5 cm in a full-term neonate. If resistance is initially met, loosen the umbilical tape or suture and manipulate the angle of approach.

Insertion of umbilical vein catheter

# Do not force the advancement.
# Secure the catheter with a suture through the cord, marker tape, and a tape bridge.
# The position of the catheter must be confirmed radiographically. A properly placed umbilical vein catheter appears to travel cephalad until it passes through the ductus venosus.
# Standardized graphs estimate the length of catheter insertion based on shoulder-to-umbilicus length. Alternatively, the shoulder-to-umbilicus length may be multiplied by 0.6 to determine a length that leaves the tip of the catheter above the diaphragm but below the right atrium.
# In an emergency resuscitation, the catheter is best advanced only 1-2 cm beyond the point at which good blood return is obtained.

No anesthesia is typically required for the procedure.

Extraglottis Devices

How to perform Combined Spinal-Epidural Obstetric Anesthesia

Femoral Nerve Block at the level of the inguinal skin crease

Femoral nerve block is commonly performed by insertion of the block needle 1-2 cm lateral to the femoral artery just below the inguinal ligament as seen in the picture which requires multiple attempts at localization of the femoral nerve Performing the block at the level of the inguinal skin crease however, has given us more consistent results in the practice as it gives more superficial position of the femoral artery and nerve, Greater width of the femoral nerve, More consistent femoral nerve-artery relationship.

Steps of of the Technique:

A 22G, 50 mm short bevel insulated needle attached to nerve stimulator (0.6 mA) is inserted adjacent to the lateral border of the femoral artery at the level of inguinal crease, a skin fold 3 to 6 cm below and parallel to the inguinal ligament. The needle is slowly advanced at an angle of 60° cephalad to the horizontal plane while seeking a quadriceps muscle twitch (rhythmic movements of the patella).

If a quadericeps muscle twitch is not obtained, the needle is withdrawn and redirected 10° laterally (The Figure below). If this maneuver does not elicit a quadericeps muscle twitch, the subsequent needle insertions should be placed at increments of 5 mm lateral to the previous insertion sites. Once a quadericeps muscle twitch is obtained at <0.4 mA, the local anesthetic of choice is injected. However, when the initial response is a sartorius muscle twitch, the quadriceps muscle twitch is sought by incrementally re-directing the needle laterally 10° at a time, and advancing the needle several mm beyond the point at which the sartorius muscle twitch was induced. After injecting 30 ml of local anesthetic the onset of blockade is expected within 3-5 minutes when the current is < 0.4 mA. The block is documented by loss of sensation in the anterio-medial thigh and saphenous nerve distribution, as well as the presence of quadriceps muscle relaxation.

Agents for Spinal anesthesia

"Little Boys Prefer Toys":

• Lidocaine
• Bupivicaine
• Procaine
• Tetracaine

NOTES :
1-Lidocaine provides a short duration of anesthesia and is primarily useful for surgical and obstetrical procedures lasting less than one hour.

2-Tetracaine Vs Bupivacaine:Tetracaine and bupivacaine are used for procedures lasting 2 to 5 hours. Tetracaine appears to provide a somewhat longer duration of anesthesia and a more profound degree of motor block than does bupivacaine. On the other hand, compared with tetracaine, bupivacaine has been demonstrated to be associated with a decreased incidence of hypotension.
In addition, bupivacaine may be better than tetracaine for use in orthopedic surgical procedures since it appears to be associated with a lower incidence of tourniquet pain.

3-Vasoconstrictors can prolong the duration of spinal anesthesia of all three agents. However, the greatest duration is seen when vasoconstrictors are added to tetracaine solutions.

Ultrasound-Guided Femoral Nerve Block

Extraglottis Devices

Principles of EndotracheaI Intubation During General Anaesthesia

Mallampati test

To try to identify patients who will prove difficult to intubate.The patient sits in front of the anaesthetist and opens the mouth wide.
The patient is assigned a grade according to the best view obtained.

View obtained during Mallampati test:
1. Faucial pillars, soft palate and uvula visualised
2. Faucial pillars and soft palate visualised, but uvula masked by the base of the tongue
3. Only soft palate visualised
4. Soft palate not seen.

Clinically, Grade 1 usually predicts an easy intubation and Grade 3 or 4 suggests a significant chance that the patient will prove difficult to intubate.

The results from this test are influenced by the ability to open the mouth, the size and mobility of the tongue and other intra-oral structures and movement at the craniocervical junction.

Local anaesthesia technique for Middle ear and Mastoid

Modified ASA Grade for assessment of fitness for anaesthesia and surgery

ASA or American Society of Anesthesiologists grade is the most commonly used grading system to accurately predict morbidity and mortality.
Medical co-morbidity increases the risk associated with anaesthesia and surgery,50% of patients presenting for elective surgery are ASA grade 1.

Corresponding grade in each classification for ASA and revised assessments

Common Nerve Blocks Used by Ophthalmologists

ADMINISTERING LOCAL NERVE BLOCKS

The most common local anesthetic mixture is 2% lidocaine with 1:100,000 epinephrine to provide some hemeostasis. Addition of 0.5% bupivacaine will provide longer anesthesia (~6-8 hours) for lengthy procedures. The following diagrams illustrate common local nerve blocks used in ophthalmology.

Diagram 1: Common Periorbital Nerve Blocks


Diagram 2: Common Facial Nerve Blocks

Digital Local Anaesthesia