15. Complications during and after local anesthesia. Types of prevention. Basic principles of treatment

Question 1

Maximum dose of local anesthetics

Answer 1

• Lidocaine: 7mg/kg
• Mepivacaine: 6.6 mg/kg
• Prilocaine: 6.0 mg/kg
• Articaine: 7.0 mg/kg
• Procaine: 10mg/kg
• Bupivacaine: 2.2 mg/kg

Question 2

Effect of Epinephrine in La

Answer 2

🔹Vasoconstriction
🔹Reduced bleeding
🔹Prolonged anaesthesia

Question 3

Effects of Epinephrine injection into vessel

Answer 3

🔷Systemic absorption-systemic toxicity
🔹Cardiovascular effects- tachycardia , Hypertension, arrhythmias
🔹CNS effects- dizziness, tremors, seizures
🔹Local tissue ischemia->necrosis

Question 4

Epinephrine effect on heart

Answer 4

🔹Secreted by adrenal glands
🔹Binds to beta adrenergic receptors on heart muscle cells
🔹Increases HR and strength of contractions->increased blood supply
🔹Raises Bp

Question 5

Role of epinephrine in allergic reactions

Answer 5

🔸Inhibits release of inflammatory mediators
🔸Histamine, leukotrienes

Question 6

How epinephrine counteracts effects of vasodilation and increased vascular permeability during allergic reactions

Answer 6

🔸Induces vasoconstriction and reduces vascular permeability

Question 7

Importance of bronchodilation during severe allergic reactions

Answer 7

🔸Improved airflow

Question 8

Effects epinephrine has on cardiovascular system during allergic reactions

Answer 8

🔸Maintains blood pressure and cardiac output

Question 9

How Articaine has better penetration into tissues than lidocaine

Answer 9

🔸Presence of ester group in its structure
🔸Allows better diffusion

Question 10

Advantages of Articaines improved penetration

Answer 10

🔸More profound anaesthesia at lower doses

Question 11

Main effects of epinephrine in allergy

Answer 11

🔸Vasoconstriction (reduces swelling)
🔸Bronchodilation (improved airflow)
🔸Cardiovascular effects
🔸Suppression of inflammatory mediators

Question 12

Active ingredient of Ubistein

Answer 12

Articaine and epinephrine

Question 13

Active ingredient of Scandonest

Answer 13

Mepivicaine and epinephrine

Question 14

Active ingredient of xylodren

Answer 14

Lidocaine and epinephrine

Question 15

Active ingredient of dentocain

Answer 15

Articaine and adrenaline

Question 16

Active ingredient of septonest

Answer 16

Adrenaline and Articaine

Question 17

Factors that affect intensity and duration of LA’s

Answer 17

🔸Tissue blood flow
🔸Activity of plasma cholinesterase
🔸Vasoconstrictor use
🔸pH of tissue
🔸Dose of La

Question 18

How infection hinders effect of La

Answer 18

🔸Creates acidic environment->decreases pH of tissues
🔸Alters ionisation and ability to penetrate nerve fibres->
🔸Reduces the potency and duration of LAs

Question 19

Strategies to overcome resistance of LA in infected tissues

Answer 19

🔸Antibiotics and anti inflammatory agents (reduce inflammation and acidity)
🔸Regional nerve blocks and intravenous sedation

Question 20

Overdose of LAs can cause

Answer 20

🔹Severe hypotension (Vasodilation)
🔹Seizures
🔹Respiratory depression

Question 21

Problems that may occur before administering anesthesia

Answer 21

* Fear of the Patient:
=>syncope (fainting) or collapse
* Reduces efficiency of the anesthesia.
* Collapse:=> Severe vascular insufficiency leading to a sudden drop in blood pressure.
* Impossibility to Introduce the Anesthetic Solution in the Right Place:
* Cant open mouth wide=>
* Inflammatory (trismus) or non-inflammatory contractures
* Ankylosis of the mandibular joints.

Question 22

Syncope, and its main characteristics

Answer 22

• Transient loss of consciousness and postural tone=>
• Spontaneous recovery without neurological deficit

Question 23

Most common cause of unconsciousness in a dental office setting

Answer 23

Vasovagal syncope

Question 24

Psychogenic and non-psychogenic causes of vasovagal syncope

Answer 24

1. Psychogenic=>
   * Fright
   * Anxiety
2. Non-psychogenic=>
   * Prolonged standing and dehydration

Question 25

What surgeon should consider when a patient experiences syncope

Answer 25

* Usually a benign, self-limiting event=> * Rule out other more serious etiologies of unconsciousness

Question 26

Cardiac causes of syncope

Answer 26

Obstructive outflow diseases such as aortic stenosis

Question 27

Neurogenic causes of syncope

Answer 27

Seizures, transient ischemic attack, migraines

Question 28

How orthostatic hypotension can lead to syncope

Answer 28

* Patients with depleted intravascular volume=> * Side effect of drugs=> antidepressants and antihypertensives * Patients with autonomic instability=> * Diabetes mellitus

Question 29

Hypoglycemia relation to syncope

Answer 29

Rare cause of syncope

Question 30

Patients in which vasovagal or vasodepressor syncope generally the etiology

Answer 30

Young, healthy patients

Question 31

Stages of syncope and the symptoms

Answer 31

1. Presyncopal Stage: * Blood pressure and heart rate drop 2. Syncope Stage: * Irregular breathing * Pulse thready, blood pressure can drop to extremely low levels * Unconsciousness can last from seconds to several minutes after placement in the supine position 3. Postsyncope Stage: * Rapid recovery * Pallor, nausea, disorientation may persist

Question 32

Management steps for syncope in an emergency situation

Answer 32

* Stop the procedure immediately * Trendelenburg position and administer oxygen * If unconsciousness =>,basic life support protocol: call for help, assess airway, breathing, and circulation * Chin lift or jaw thrust to open the airway. * If breathing and circulation present=> crush an ampule of ammonia under the patient’s nose to hasten recovery * Call emergency medical services if unconsciousness lasts beyond 10-15 minutes. ## Footnote Failure to lay the syncopal patient flat can result in brain damage or death.

Question 33

Collapse

Answer 33

* Severe vascular insufficiency => to a sudden drop in blood pressure * Consciousness is preserved * Patient may feel weak, dizzy, have shallow breathing Management: Requires immediate medical treatment

Question 34

Complications during local anesthesia

Answer 34

* **Allergic Reactions * Toxic Reactions: * Fracture of the Injection Needle: * Post-Injection Pain and Inflammatory** Complications:=> * High concentration anesthetics * Periosteum injury, tissue infection, or use of non-sterile solutions.

Question 35

Anaphylaxis and how does it occurs

Answer 35

* Type I hypersensitivity reaction=> antigen binds to IgE antibodies on mast cells and basophils=> * Systemic release of immunologic mediators

Question 36

Common clinical presentations of anaphylaxis

Answer 36

* Urticaria (hives) and/or angioedema (swelling) * Respiratory compromise and cardiovascular collapse=> * Usual causes of death in anaphylaxis

Question 37

Common causes of anaphylaxis in a surgical practice

Answer 37

* Drugs such as penicillin and aspirin * Exposure to latex

Question 38

Conditions that must be differentiated from anaphylaxis

Answer 38

* Vasodepressor syncope * Local anesthetic overdose * Panic attack, cardiac arrest, foreign body aspiration

Question 39

How initial signs and symptoms of anaphylaxis be managed

Answer 39

* Procedure stopped immediately * Airway, breathing, circulation, and consciousness level assessed, * Epinephrine should be administered without delay

Question 40

Role of epinephrine in managing anaphylaxis, and how it should be administered

Answer 40

* Intramuscularly or subcutaneously at a 1:1000 dilution (0.2–0.5 ml in adults or 0.01 mg/kg in children) * Injected into the lateral thigh, upper arm, or sublingually=. * Dose repeatable every 5 minutes as needed

Question 41

Position patient placed in during anaphylaxis and why

Answer 41

* Trendelenburg position (lying flat with feet elevated) * Maximize cerebral blood flow

Question 42

Additional treatments that should be considered after initial epinephrine administration in anaphylaxis

Answer 42

* Antihistamines (such as diphenhydramine) intramuscularly or intravenously at 1–2 mg/kg (up to 50 mg). * Albuterol for bronchospasm * Corticosteroids (such as hydrocortisone prevent recurrent or protracted anaphylaxis

Question 43

Why its important for all patients with anaphylaxis to be taken to an emergency department

Answer 43

Can recur

Question 44

Common causes of needle fractures during local anesthesia and their prevention

Answer 44

* Incorrect Insertion * Sudden Movements Prevention Measures=> Avoid Full-Length Insertion: * Control Patient Movement: Ensure the patient remains still * Proper Technique:

Question 45

How a fractured needle managed if it occurs during an injection

Answer 45

* Depends on whether the end of the needle is visible or not: * Visible End: grasped with a tool and carefully removed * Not Visible and No Complications=> * Not necessary to search for and remove it * Causing Complications=> * Muscle pain, contractures, or inflammatory processes=> located and removed by searching in depth

Question 46

Causes of post-injection pain and inflammatory complications and treatment

Answer 46

* High Concentration Anesthetics: * Periosteum Injury: * Tissue Infection=>if needle tip touches teeth or mucosa before injection. * Non-Sterile Solutions ## Footnote Administer antibiotics to control and prevent infection

Question 47

How injury to a blood vessel with a needle managed during local anesthesia

Answer 47

* Common in the Superior posterior alveolar nerve block=>results in hematoma formation (plexus venosus pterygoideus) * Compression=> about 5 minutes in the area of the tuber maxillae to prevent hematoma growth * Cooling and Physiotherapy=> small hematomas, cool the area for the first 24 hours and follow up with physiotherapy for faster absorption * Antibiotics for Large Hematomas: * Suppuration Management: If suppuration occurs, make an incision, provide drainage, and treat as for an abscess ## Footnote -For large hematomas or patients with concomitant diseases like diabetes, prescribe antibiotics to prevent inflammatory complications.

Question 48

Prevention of vessel injury

Answer 48

* Knowledge and Technique * Aspiration Before Injection

Question 49

Reflex contracture

Answer 49

* Limited lower jaw movement (N. alveolaris inferior) La * Needle Tip Bending: The needle tip bending upon bone contact. * Muscle Fiber Tear: => * M. pterygoideus medialis=> pain and restricted jaw movement from hematoma, myositis, or scarring

Question 50

Reflex contracture treatement

Answer 50

* Analgesics and Anti-inflammatory Drugs: To manage pain and inflammation. * Physiotherapy: To aid in recovery and restore movement.

Question 51

How aspiration or swallowing of an injection needle managed

Answer 51

* Natural Discharge: The needle usually passes naturally through GIT in 2-3 days * X-rays: track the needle's path. * Surgical Intervention: If the needle is not discarded within 4 days=> operative intervention. * Diet Management=>avoid peristalsis-enhancing or cleansing medications. * Asphyxia Management: If the needle is aspirated causing asphyxia=> * Coniotomy in case of stenotic asphyxia * Partial airway patency=> otolaryngologist-bronchoscopist and anesthesiologist urgently

Question 52

Prevention strategies for needle aspiration

Answer 52

* Use of Gauze: Especially in children and restless patients=> * keep the needle attached to the syringe and in the operator's hands

Question 53

Emphysema in the context of local anesthesia complications

Answer 53

* Increased air content in tissues * Often=> upper jaw anesthesia from the vestibular side * Air pushed into the soft tissue during injection or needle removal * Swelling * Crepitation: => on palpation in the affected area

Question 54

Emphysema management in the context of local anesthesia complications

Answer 54

* Press the Area=>about 5 minutes to stop further air ingress. * Resolution: The condition typically resolves within 2-3 days without special treatment.

Question 55

Causes of facial nerve paresis or paralysis during dental procedures

Answer 55

* improper anesthesia => N. Alveolaris inferior. * Penetration of the injection needle behind the posterior edge of the mandibular ramus=> parotid gland * transient=>disappears after the anesthetic wears off

Question 56

How paresthesias or neuritis develop in dental procedures, and their clinical manifestations

Answer 56

* Branches of the trigeminal nerve are damaged=> * Injection Techniques=

Question 57

Most common nerves injured

Answer 57

Inferior alveolar, Mental and lingual

Question 58

Symptoms of nerve injury

Answer 58

Burning sensation - Pins and needles - Biting of tongue and lips - Abnormal chewing - Burns when consuming food

Question 59

Conditions of nerve trauma

Answer 59

- Anaesthesia - Hypesthesia - Paraesthesia - Dysesthesia

Question 60

Classifications of nerve injury

Answer 60

- Neurapraxia - Axonotmesis - Neurotmesis -

Question 61

Neurapraxia

Answer 61

- Small contact w/ nerve - Favourable prognosis - Complete recovery→rapid

Question 62

Axonotmesis

Answer 62

- Injury without anatomic severance of endoneurium - Slower recovery than neurapraxia(paraesthesia 6-8 weeks after injury) - Risk of remaining sensory disturbance

Question 63

Complications that can arise from infraorbital anesthesia, and how are they managed

Answer 63

* Anesthetic solution penetrates into the orbit=> * Double vision (diplopia)=> * Transient and typically resolves without any long-term effects on vision

Question 64

causes and management of post-injection tissue necrosis in dental anesthesia

Answer 64

* Rapid Subperiosteal Injection: * Excess Anesthetic Amount * Vasoconstrictors * =>>> * Detachment of the periosteum from the underlying bone=> * Necrosis of soft tissues and underlying bone (sequestration of the hard palate)