Complications and management of local anesthesia

1. BY MUHAMMAD RAFAY IMRAN

2. What is Local Anesthsia ?
 Local anesthesia is any technique to induce the absence of sensation in a
specific part of the body.

3. Suggested Maximum dose of Local
Anesthetics
Drug Common Brand Concentration Max. dose (mg/kg)
Lidocaine Xylocaine 2% 5
Lidocaine with
Epinephrine
Xylocaine with
Epinephrine
2% lidocaine with
1:100,000
Epinephrine
5
Mepivacine Carbocaine 3% 5
Mepivacaine with
levonordefin
Carbocaine with
Neo-Cobefrin
4% 5
Prilocaine Citanest 4% 5
Bupivacine with
epinephrine
Marcaine with
epinephrine
0.5% bupivaine
1:200,000
epinephrine
1.5
Etidocaine with
epinephrine
Duranest with
epinephrine
1.5% etidocaine
1:200,000
epinephrine
8
*Maximum doses are those for normal healthy individuals *Maximum dose of epinephrine is 0.2mg per appointment

4. Local Complications of Local
Anesthesia
 Needle Breakage
 Its not a significant problem if the needle can be removed without surgical
intervention.
 Management : It involves the immediate referral to patient to an
appropriate specialist eg. Oral and maxillofacial surgeon.
 CT Scanning has been recommended to identify the location of the
retained needle.
 Needle is removed by specialist while the patient is under general
anesthesia.

6. Prolonged Anesthesia Or Paresthesia
 Trauma to any nerve may lead to paresthesia.
 Usually Paresthesia resolve within approximately 8 weeks without
treatment. Only if the damage to nerve is severe , paresthesia will be
permanent but this occurs rarely.

7. Management of Paresthesia
Management
1. Reassuring. Speak to the patient personally Explain the patient that paresthesia is
not uncommon , arrange the next appointment.
2. Examine the patient.
Determine the degree and extent of Paresthesia. Record all the findings on the
patient’s chart using the patient’s own descriptors such as “Hot” , “Cold” , “Painful”
“increasing” , “decreasing” and “Staying the same”
3. Send the patient to Oral and maxillofacial surgeon for the surgery (if required)
4. Reschedule the patient until Paresthesia is resolved.
5. Continue dental treatment but avoid administrating the Local Anesthesia.

8. Facial Nerve Paralysis
 Usually caused when LA is introduced into the capsule of Parotid Gland.

9. Management
1.Reassure the patient. Explain the it will resolve in few hours.
2.Contact lenses should be removed until muscular movement returns.
3.Eye patch should be applied to the affected eye until muscle tone returns.
4.Record the incident on the patient’s chart
5.Although no contraindication is known to reanesthezing the patient. Can continue
dental treatment.

10. Trimus
 Trauma to muscle or blood vessels in the infratemporal fossa is the most
common causative factor in trismus associated with dental injections of local
anesthesia.
 Management : Patient reports pain and some difficulty in opening his or her
mouth on the day after dental treatment.
 Arrange an appointment for examination. Prescribe heat therapy, warm saline
rinses , analgesics and in necessary muscle relaxants.
 The Patient should be advised to initiate physiotherapy consisting of opening
and closing the mouth for 5 minutes every 3-4 hours.
 Record the incident, findings and treatment on the patient’s dental chart.
Avoid further dental treatment until trismus is resovled.
 If it is not improved within 2-3 days refer to Oral and maxillofacial surgeon.

11. Soft tissue Injury.
 Management
 Analgesics for pain
 Antibiotics (if needed)
 Warm saline rinses.
 Petroleum jelly or any other lubricant to cover a lip lesion and minimize
irritation

12. Hematoma
The effusion of blood into extravascular spaces can be caused during
administration of local anesthesia.

13. Management of Hematoma
 Immediate Management of Hematoma
 Whenever local anesthesia is given, and this is followed by the formation of a
swelling of any size, its advised to apply direct pressure on the site where there
is the swelling or bleeding or the accumulation of blood. For most of the cases,
the blood vessel lies in between the skin and bone, and when the injection
leads to bleeding, the pressure has to be applied in these areas for more than
2 minutes. This way of management would effectively stops the bleeding.
 Hematoma due to Inferior Alveolar Nerve Block: Whenever hematoma
occurs due to the administration of the Inferior alveolar nerve block, the
pressure has to be applied to the medial aspect of the mandibular ramus.
Clinical manifestations of the hematoma are intraoral: possible tissue
discoloration and probable tissue swelling on the medial (lingual) aspect of the
mandibular ramus.

14. Continued.
 Hematoma due to Anterior Superior alveolar (Infraorbital) nerve block: Pressure
has to be applied to the skin directly over the Infraorbital Foramen. Clinical
manifestation is discoloration of the skin below the lower eye lid. Hematoma is unlikely
to arise with Anterior Superior Alveolar nerve block because the technique described
requires application of pressure to the injection site throughout drug administration and
for a period of 2 to 3 minutes after, thus there is no potential injury or cause for
Hematoma.
 Hematoma due to Incisive (mental) nerve block: Just like the ASA nerve block, here
the pressure is applied directly over the mental foramen, on the skin or mucous
membrane while administering the local anesthesia, and thus the risk of Hematoma
formation is largely reduced. Clinical manifestations are discoloration of skin over the
mental foramen or swelling in the mucobuccal fold in the region of the mental foramen.
 Hematoma due to Buccal nerve block or any palatal injection: Place pressure at the
site of bleeding, and it would slowly get reduced. In these injections the clinical
manifestations of hematoma are usually visible only within the mouth

15. Continued.
 Subsequent Management of Hematoma
 Once you have identified Hematoma, and the immediate steps are taken, the patient may be discharged
after the bleeding stops. Note the hematoma on the patient’s dental chart.
Advise the patient about possible soreness and limitation of movement (trismus). If either of these
develops, begin treatment as described for trismus. There will likely be discoloration as a result of
extravascular blood elements, which gradually gets resorbed over 7 to 14 days.
 If there is any soreness, advise the patient to have any analgesic such as Aspirin. After the incident, try to
avoid applying heat to that area for at least 6 hours, because heat produces vasodilation, and this may
further increase the size of the Hematoma. Heat may be applied to the region beginning the next day. It
serves as an analgesic, and its vasodilating properties may increase the rate at which blood elements are
resorbed, although its benefits are debatable.
 The patient should apply warm moist towels to the affected area for 20 minutes every hour.
 After the recognition of the hematoma formation, initially Ice may be applied, as it would act as both an
analgesic and a vasoconstrictor, and it may aid in minimizing the size of the hematoma.
 Time (tincture of time) is the most important element in managing a hematoma. With or without treatment,
a hematoma will be present for 7 to 14 days. Avoid additional dental therapy in the region until symptoms
and signs resolve.

16. Burning on injection
 Burning sensation that occurs during injection of local anesthesia.
 Management : It do not lead to prolonged tissue involvement, formal
treatment is usually not indicated.

17. Infection
 Infection because of local anesthesia in dentistry is extremely rare.
 Management : Possibility of a low grade infection should be entertained.
Prescribe Pencilin for 7-10 days (250mg tablets). Erythromycin can
prescribed if patient is allergic to pencillin.

18. Edema
 Management :
 Usually edema is resolved within several days without formal treatment.
 After hemorrhage , edema resolves slowly (7-14 days)
 Allergy induced is life threatening. If edema occurs in buccal soft tissues
and there is no involvement of airway then treatment consist of
intramuscular and oral histamine blocker.
 If edema occurs any area where it compromises the breathing. Treatment
consist of :

19. Management of Allergic response to
LA (compromising airway)
Management
If patient is unconscious , place him/her on supine position
Airway , breathing and circulation should be monitored and emergency medical
services should be summoned
Epinephrine is administered : 0.3 mL in adults and 0.15 ml in children (15-30Kg) every 5
minutes until respirartory distress is resolved
Histamine blocker and corticosterioid is administered IM or IV
Patient’s condition is thoroughly evaluated before next appointment

20. Sloughing of Tissues.
 Management : It maybe symptomatic :
 Analgesics
 It maybe resolved in 7-10 days

21. Postanesthetic Intraoral lesions
 Management :
 Primary management is symptomatic.
 Reassure the patient that situation is not caused by bacterial infection.
 No management is necessary if pain is not severe
 Topical anesthetic solutions maybe applied as needed to the painful areas.
 Ulceration last 7-10 days with or without treatment.

23. Systemic Complications of Local Anesthesia
 Manifestions  Management
 Mild Toxicity : Confusion , slurred
speech anxiety and talkativeness
 Stop administration of LA
 Monitor All vital signs
 Observe in clinic for 1 hour
 Moderate Toxicity : Stuttering speech ,
nystagmus , tremors , headache ,
dizziness , blurred vision , drowsiness
 Stop Administration of LA
 Place in Supine Position
 Monitor all Vital Signs
 Administer Oxygen
 Observe in clinic for 1 hour
 Severe Toxicity : Seizure , Cardiac
dysrhythmia or arrest
 Place in supine position
 If seizure occurs protect patient from
nearby objects
 Monitor all vital signs
 Administer oxygen
 Administer Diazepam 5-10mg slowly or
midazolam 2-6mg slowly
 Transport to emergency care facility

24. How to prevent systemic complications
of Local Anesthesia
 Prevention of toxicity involves several factors
 First the dose to be used should be the least amount of local anesthetic
necessary to produce the intensity and duration of pain control.
 The patient’s age , lean body mass , liver function and the history of
problems with local anesthetics must be considered.
 Second the dentist should give the required dose slowly, avoiding
intramuscular injection and use vasoconstrictors.
 Avoid use of topical LA in wounds or on mucosal surfaces as it allows rapid
entry of local anesthetic in systemic circulations
 Third is the choice of anesthetic.