EMERGENCY SEDATION AND PAIN MANAGEMENT - PART 9 doc

The mnemonic NAVel for Nerve – Artery – Vein in a direction toward the navel will aid providers in 234 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient... If a t

clinical progression of anesthetic toxicity from subtle

neurological symptoms to refractory seizure and

ulti-mately cardiovascular collapse

When using any local anesthetic, it is critical to pay

close attention to the volume and concentration of drug

used This concern is especially relevant with large

wounds and/or patients with a low body weight When

the use of a large quantity of local anesthetic seems

unavoidable, alternative regional blocking techniques

and supplementation with systemic analgesics and/or

anxiolytics should be strongly considered

Pitfalls

1 Releasing the tourniquet prematurely, thus

allow-ing a large bolus of anesthetic to reach the systemic

circulation

2 Not inflating the tourniquet tight enough (250–300

mmHg) to control the distribution of anesthetic

3 Using a blood pressure cuff instead of a

specifi-cally designed tourniquet

4 Increasing the risk of tissue ischemia by employingthe tourniquet for longer then 90 min

5 Not using adequate padding surrounding thetourniquet to alleviate ecchymosis and minimizetourniquet pain

Intercostal BlockGeneral

Rib fractu res are comm on injuries (Fig ure 34-2 ).Movement and normal respiration makes adequate paincontrol a challenge in these patients This is especiallyrelevant in the elderly, where rib fractures are associatedwith significant morbidity and mortality Intercostalnerve blocks offer an alternative to parental analgesiafor both inpatients and those being discharged home.Intercostal blocks provide analgesia over the correspond-ing chest and abdominal area by blocking the cutaneousdistribution of the corresponding intercostal nerves.Although there are no prospective controlled trialscomparing parental analgesia with intercostal nerve

Figure 34-2 Intercostal block On the left: Retraction of the skin cephalad from the lower edge of the rib

exposes the site of entry The needle is inserted at an 80angle, tip cephalad, until contact is made with

the lower rib edge When the skin is released, the needle is allowed to slide caudad to the lowermost

rib border The needle is advanced 3 mm, aspiration is attempted, and 2–5 ml of anesthetic is injected

as the needle is inserted and withdrawn 1 mm in each direction.

On the right: A cross-section of the chest shows the relevant branching of a typical intercostal nerve.

Blocks are commonly performed at (a) the mid-axillary line and (b) the posterior axillary line.

blocks, some evidence suggests enhanced pain control

and increased lung function associated with intercostal

nerve blocks

The reported incidence of pneumothorax associated

with intercostal nerve block application appears to be

low with the highest incidence reported to be 1.4% for

each individual block The duration of anesthesia

achieved from this block has been estimated as 8–18 hr

Anatomy

The intercostal nerve originates from the thoracic nerve

and continues anterior around the chest wall giving off

the lateral cutaneous branch Within the subcostal grove

of the rib, the nerve runs inferior to the artery and vein

(‘‘VAN’’) The intercostal nerve block involves the

deposition of anesthetic into this groove The site of

injection is approximately 6 cm lateral to the midline,

just lateral and anterior to the paraspinous muscles Ribs

1–6 are rarely blocked owing to the position of the

scapula and rhomboid muscles

Distribution of anesthesia

This block provides anesthesia in a band-like fashion

around the chest wall of the corresponding rib Best

results are achieved by blocking the affected rib, as well

as one above and one below the site of injury

Technique

To ensure a successful nerve block, the intercostal block

must be performed proximal (medial) to the fracture

site The most common injection site is posterior to the

midaxillary line, which ensures blockage of the lateral

cutaneous and anterior branch of the intercostal nerve

Identify the rib to be blocked and prepare the surgical

field above and below the affected rib For multiple

blocks, it is recommended that the injection site be

identified and marked prior to preparing the surgical field

With the noninjection hand, palpate the inferior

border of the rib to be blocked and retract the skin

cephalad Insert the needle bevel up holding the syringe

lower then the entry site to achieve an angle 10–15 off

the perpendicular with the needle tip cephalad Raise a

wheal of anesthetic in the subcutaneous space and

continue advancing the needle until it contacts bone

The needle should be resting at the inferior border of the

rib to be blocked

Release the skin being retraced cephalad at the sametime maintaining a cephalad direction of the needle.The needle is now ‘‘walked’’ caudally until it drops offthe inferior edge of the rib Advance the needle approxi-mately 3 mm, aspirate for blood, and inject 2–5 ml ofanesthetic

In experienced hands, the incidence of complicationsfrom this approach is low and a postprocedure chestX-ray is not routinely indicated, unless the patientdevelops clinical signs of a pneumothorax includingcoughing, shortness of breath, or hypoxia

Pitfalls

1 Holding the needle perpendicular to the rib willdecrease the chance of a successful block because thenerve is cephalad to the inferior margin of the rib

2 Not blocking the rib above and below the fracturedrib to ensure nerves from adjacent ribs, with inner-vation around the area of the fracture, are blocked

Femoral Nerve BlockGeneral

Femoral nerve blocks offer excellent analgesia for patientswith hip and proximal femur fractures (Figure 34-3) The

‘‘three-in-one’’ technique, first described by Winnie et al

in 1973, relies on anesthetic block of the femoral, rator, and the lateral femoral cutaneous nerves

obtu-This procedure is accomplished by injecting 20–60 ml

of local anesthetic into the femoral neural sheath whileholding distal pressure so as to promote cephalad spread

of the anesthetic and distribution of anesthesia to allthree nerves The ‘‘three-in-one’’ technique is increas-ingly used as part of the initial management of patientswith hip fractures

Whether the goal is to block only the femoral nerve or

a three-in-one block, the landmarks and procedures arevery similar with the only difference being distal pres-sure in a three-in-one block to promote cephalad dis-tribution of anesthesia

Anatomy

At the level of the inguinal ligament the femoral nerve ispositioned lateral and slightly deeper then the femoralartery The mnemonic NAVel for Nerve – Artery – Vein

in a direction toward the navel will aid providers in

234 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient

remembering that the femoral nerve is located lateral to

the femoral artery

The femoral nerve provides motor innervation to the

muscles of the anterior thigh and sensory innervation to

the anterior thigh and the medial leg

Distribution of anesthesia

The femoral nerve block will provide anesthesia to the

anterior thigh and medial leg If a three-in-one block is

applied, this will provide anesthesia to the anteriorthigh, medial leg, and to the muscles innervated by theobturator and the lateral femoral cutaneous nerves

TechniqueIdentify the femoral artery on the affected side at thelevel of the inguinal ligament Prepare the surgical fieldand palpate the femoral artery with the noninjectinghand Continue to palpate the femoral artery with the

Figure 34-3 Femoral Isolation of an area immediately lateral to the femoral artery and 1–2 cm caudad

to the inguinal ligament provides the point of insertion The needle enters at 90to the skin and to the

subjacent neurovascular structures until either it pulses laterally or a paresthesia is felt 10–20 ml of

anesthetic are deposited after negative aspiration.

noninjecting hand throughout the procedure to avoid

inadvertent puncture

With local anesthetic, raise a wheal and anesthetize

approximately 1 cm lateral to the femoral artery Insert

the needle 1 cm lateral to the artery at the level of the

femoral crease The needle should be directed slightly

cephalad

Paresthesia over the anterior thigh should be elicited

to ensure proximity of the femoral nerve For optimal

results, a peripheral nerve stimulator is recommended to

ensure correct location

Aspirate prior to injection of approximately 20–30 ml

of anesthetic If paresthesia cannot be elicited, a fan-like

technique should be employed to distribute 10–20 ml

medial and lateral to the injection site Aspirate prior to

each injection

When performing a three-in-one block, distal

pres-sure should be applied after confirmation of needle

position by either paresthesia or by peripheral nerve

stimulator (recommended)

When using a peripheral nerve stimulator, the correct

injection point is confirmed by contraction of the

quadriceps muscles and subsequent patellar movement

Sartorius contraction may mimic quadriceps

tion but will not move the patella If sartarius

contrac-tion is noted, the needle should be reposicontrac-tioned slightly

lateral and deeper to isolate the femoral nerve and

subsequent quadriceps contraction The three-in-one

block success is predicated upon holding distal pressure

for approximately 5 min to ensure that the anesthesia is

deposited in the nerve sheath Allow 30 min for effect of

this block

Pitfalls

 Not holding distal pressure when performing a

three-in-one block

 Not using a peripheral nerve stimulator when

performing a three-in-one block

 Not aspirating prior to injection to ensure against

inadvertent artery puncture

PEDIATRIC CONSIDERATIONSAlthough regional anesthesia is commonly used andpromoted by pediatric anesthesiologists, there is a paucity

of literature addressing the use of these techniques side of the operating room environment and population

out-FOLLOW-UP/ CONSULTATION CONSIDERATIONDocumentation of a complete neurological exam aroundthe affected area is critical both prior to and followingany regional block procedure Systemic or oral analgesiashould be utilized to supplement the anesthetic benefit of

3 Haasio J Cubital nerve block vs haematoma block for themanipulation of Colles’ fracture Ann Chir Gynaecol1990;79:168–171

4 Handoll HH, Madhok R Closed reduction methods fortreating distal radial fractures in adults Cochrane DatabaseSyst Rev 2003;1:CD003763

5 Farrell RG, Swanson SL, Walter JR Safe and effective IVregional anesthesia for use in the emergency department.Ann Emerg Med 1985;14:239–243

6 Strømskag KE, Kleiven S Continuous intercostals andinterpleural nerve blockades Tech Reg Anesth Pain Manage1998;2:79–89

7 Karmakar MK, Ho AMH Acute pain management ofpatients with multiple fractured ribs J Trauma 2003;54:612–615

8 Shanti CM, Carlin AM, Tyburski JG Incidence of thorax from intercostal nerve block for analgesia in ribfractures J Trauma-Inj Infect Crit Care 2001;51:536–539

pneumo-9 Osinowo OA, Zahrani M, Softah A Effect of intercostalnerve block with 0.5% bupivacaine on peak expiratoryflow rate and arterial oxygen saturation in rib fractures

J Trauma-Inj Infect Crit Care 2004;56:345–347

10 Winnie AP, Ramamurthy S, Durrani Z The inguinalparavascular technique of lumbar plexus anaesthesia The

‘‘3-in-1 Block.’’ Anesth Analg 1973;52:989–996

236 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient

35 Regional Anesthesia for Dental Pain

The Syringe and NeedleSyringe

NeedlesThe cartridge

PAIN MANAGEMENT

AnatomyTechniquesTopical anesthesiaIntraoral anesthesiaSupraperiosteal InjectionGeneral

Distribution of anesthesiaTechnique

Pitfalls/tipsGreater Palatine Nerve BlockGeneral

Distribution of anesthesiaTechnique

Pitfalls/tipsNasopalatine Nerve BlockGeneral

Distribution of anesthesiaTechnique

Pitfalls/tipsInferior Alveolar Nerve BlockGeneral

Distribution of anesthesiaTechniques

Pitfalls/tips

FOLLOW-UP/ CONSULTATION CONSIDERATIONS

BIBLIOGRAPHY

237

SCOPE OF THE PROBLEM

Complaints pertaining to the teeth and face are common

and the vast majority of these are pain related The

inci-dence of dental-related complaints presenting to

emer-gency departments (EDs) appears to be rising, ranging

from 0.4% to 10.5% of ED visits with over 3 million

patients seen in EDs between 1997 and 2000

Although treating dental and facial emergencies can be

challenging and frustrating, these injuries can also be

immensely satisfying when the emergency physician has a

basic understanding of dental and facial neuroanatomy as

well as an understanding of the simple techniques required

to relieve dental and facial pain There is no more

appre-ciative patient than one relieved of severe pain

Many emergency physicians are called upon to treat

dental problems, and it is therefore essential to have a

diagnostic and treatment plan in place to facilitate patient

care Dental and facial blocks should be an integral part of

such a plan The emergency care provider should have aworking knowledge of the names of the teeth and thefacial anatomy (Figure 35-1)

CLINICAL ASSESSMENTBefore performing any local or regional anesthesia, theclinician should determine whether a patient can toler-ate, both physically and psychologically, the plannedprocedure This assessment is important because localand topical anesthetics may have systemic effects as well

as local and regional effects Likewise, many patientshave psychogenic reactions, such as hyperventilationand vasodepressor syncope not from the medication,but from the procedure

The clinician should obtain as much of the patient’sphysical and historical status as possible in preparation

to the procedure An adequate history and physicalexamination will lead to a minimum of life-threatening

14

15 16

17

18

19

20 21

22 23 24 25 26 27 28 29 30 31 32

1 2 3 4 5 6 7

Central incisors

Central incisors

Lateral

Lateral

Canines (cuspids)

Canines (cuspids)

First premolars (Bicuspids)

First premolars (Bicuspids)

Second premolars (bicuspids)

Second premolars (bicuspids)

Figure 35-1 Names and location of teeth Reproduced with permission from Kip Benko.

238 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient

emergencies from the procedure and interventions

associated with dental procedures

Specific questions to consider are as follows:

1 Has the patient had an adverse experience during

dental treatment?

2 Has the patient taken any recent medications,

street drugs, or herbal remedies in the last 12 hr?

3 Is the patient allergic to lidocaine, benzocaine,

adrenaline, epinephrine, or novocaine?

4 Has the patient previously had excessive bleeding

or on anticoagulants, such as coumadin, aspirin,

etc.?

5 Does the patient have heart failure or a recent heart

attack? Has the patient had a history of valvular

heart disease? Local anesthetic injection does not

require antibiotic prophylaxis, even in the patient

with known valvular disease

6 Does the patient have a history of epilepsy or

seizures? Stress and hyperventilation may provoke

a seizure in otherwise controlled patients

7 Does the patient have fainting, nervousness, or

dizzy spells? This may suggest postural

hypoten-sion, seizures, fear, or abnormal anxiety

8 Is the patient pregnant? Pregnancy is not a

contrain-dication to local anesthetics and vasopressors;

however, it is prudent to be conservative in

admini-stering any drugs to women who are pregnant

The physical examination in a patient who requires

dental anesthesia is determined by the patient’s chief

complaint If the patient has a toothache, the area of

interest, including the tooth that is causing the problem

should be examined, including the neck and

subman-dibular area for evidence of any infection or injury

PAIN CONSIDERATIONS

Anesthetic Agents

Although many anesthetic agents are available for use in

North America, only lidocaine and bupivacaine, both

amides, are typically available in most EDs Allergy to

amide anesthetic agents is rare

Lidocaine without a vasoconstrictor will last

approx-imately 10 min to 1 hr in the soft tissues and pulp of the

mouth, depending upon the strength of the lidocaine

injected Higher concentrations of lidocaine elevate the

risk of side effects, secondary to vasodilatation andsystemic uptake

Injection of a vasoconstrictive agent (e.g., rine) with lidocaine will increase the duration of clinicaleffects by a measure of two- to threefold A vasocon-strictive agent will also potentially increase hemostasiswhen simultaneously decreasing the potential for lido-caine toxicity, depending upon the vasoconstrictor used.Bupivacaine has a longer duration of action thanlidocaine This facet is an advantage when long post-procedural analgesia is desired This longer duration ofanesthetic effect may also serve to reduce the patient’sopioid requirement

epineph-Anesthetics for Topical Application during DentalProcedures

Topical anesthesia is effective only on surface mucosa(2–3 mm depth) Topical anesthesia, however, allows foratraumatic and painless needle insertion of the mucousmembrane Lidocaine and benzocaine are the two mostfrequently used topical preparations in the emergencysetti ng (Figu re 35-2 )

Gel, spray, and liquid forms are often frequently usedfor topical anesthesia preparations Gel forms allowthe practitioner to control the placement of anestheticmore accurately than either spray or liquid preparations.Although cocaine works well as a topical mucosalanesthetic, the use of cocaine has largely been replaced

by lidocaine and benzocaine owing to systemic toxicity,storage, and safety concerns

Selection of a Local Anesthetic

A reasonable approach to the selection of an appropriatelocal anesthetic includes several factors:

1 What is the length of time for which pain control isnecessary? Bupivacaine would be a good choice forlong procedures Lidocaine would be a goodchoice for a shorter acting anesthetic proceduresuch as a lip laceration where the patient wouldnot mutilate the repair unknowingly

2 What is the need for postprocedural pain control? Apatient with odontalgia from pulpitis requirespain control overnight or longer; therefore, alonger acting preparation such as bupivacainewith epinephrine would be appropriate

Figure 35-3 Metal syringes for dental anesthetic injection Reproduced with permission from Kip Benko.

Figure 35-4 A plastic syringe that uses a preloaded anesthetic vial Reproduced with permission from

Kip Benko.

The cartridge

The injection anesthetic may come in a standard, bottle

form that is common in every ED Cartridge or carpule

forms are the style used primarily by dentists (Figure 35 -5 )

The typical anesthetic carpule will contain 1.8 cc of

anesthetic

PAIN MANAGEMENT

Anatomy

The management of facial and oral anesthesia requires

a thorough knowledge of the fifth cranial nerve, the

trigeminal nerve The right and left trigeminal nerve

provides the majority of sensation to the teeth, bone, andsoft tissues of the oral cavity It also supplies sensation tothe skin of the entire face and the mucosa of the oralcavity, except for the pharynx and the base of the tongue.The motor root of the trigeminal nerve supplies themuscles of mastication as well as other small muscles inthe area

TechniquesTopical anesthesiaThe topical anesthetic benzocaine has been shown todecrease the pain of mucosal injection and, therefore,should be routinely utilized prior to performing intraoral

Figure 35-5 Preloaded anesthetic vials for dental use This figure was published in Malamed S.

Handbook of local anesthesia, 5th edn Copyright Elsevier 1997.

injection The area to be injected is first wiped clean with

gauze and then a small amount of anesthetic is applied

to the area where needle penetration is planned

A small quantity of topical anesthetic should be applied

to the cotton-tipped applicator and, subsequently, to the

mucosa (Figure 35 -6) If excessive amounts of anesthetic

are used, undesirable areas of anesthesia will result (soft

palate and pharynx), and in the case of topical lidocaine,

systemic absorption and side effects may occur

Intraoral anesthesia

The injection to be performed is determined by the

desired region of anesthesia Smaller sites may require

only an infiltration, whereas larger areas, such as the

entire unilateral mandible, may require a regional block

through the inferior alveolar nerve

Supraperiosteal Injection

General

The supraperiosteal infiltration is the most commonly

used technique in providing intraoral anesthesia to one

tooth It is a very effective technique in the management

of toothache It is also invaluable when managing tured teeth, luxated teeth, and dry sockets

frac-This injection can be used in the mandible or maxilla,but is less slightly less effective in the mandible sec-ondary to the increased thickness and density of themandibular bone A slightly larger amount of anestheticusually accomplishes adequate anesthesia

Distribution of anesthesiaThe area affected will include the entire pulp and rootarea of the tooth as well as the buccal periosteum,connective tissue, and mucous membrane associatedwith that particular tooth (Fig ure 35-7 )

TechniqueApply topical anesthetic with a cotton-tipped applicator

to the mucobuccal fold (that area of the mucosa wherethe attached gingiva of the tooth gives rise to the loosebuccal mucosa) over the desired injection area Insert

a 25- or 27-gauge short needle into the height of the

242 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient

mucobuccal fold above the apex of the tooth to be

anesthetized Keep the bevel toward the alveolar bone

and keep the needle parallel to the long axis of the tooth

Advance the needle several millimeters until the tip is

over the apex of the tooth (Fig ure 35-8 ) The depth of

injection is typically only a few millimeters When bone

is contacted, withdraw slightly Aspirate, then inject

anesthetic slowly at a rate not exceeding 2 cc/min

Injection volumes will vary, but most teeth will require

between 0.5 and 1 cc of anesthetic Anesthesia should be

obtained within 3–5 min in most cases If anesthesia is

not complete, the injection may be repeated

Pitfalls/tips

1 The deposition of anesthetic proximal to the apex of

the tooth will cause excellent soft-tissue anesthesia

but poor pulp anesthesia

2 Depths of needle placement will vary somewhat

depending upon the tooth being anesthetized, that

is, molars have longer roots than incisors

Greater Palatine Nerve BlockGeneral

It is very uncommon that the palate is injured to thedegree where palatal anesthesia becomes necessary.Knowledge of palatal blocks can be very useful not onlyfor extensive palatal lacerations, but also as an adjunc-tive technique to anesthetize the maxillary teeth.Topical anesthetic, although often tried, is not verysuccessful on the palate Distraction techniques can beeffective in minimizing the pain of injection

Distribution of anesthesiaThe posterior portion of the unilateral hard palate isaffected by this block as well as the overlying soft tissues,anteriorly as far as the first premolar and medially to themidline (Figu re 35-9 )

teeth to the midline, the body of the mandible, the

buccal mucoperiosteum, and the mucous membrane

anterior to the first mandibular molar The anterior

two-thirds of the tongue and the floor of the oral cavity

as well as the lingual soft tissues are also anesthetized

(Figu re 35-13 )

Techniques

A 25- or 27-gauge long needle is the recommended

needle size for the inferior alveolar nerve injection The

target area is the inferior alveolar nerve as it passes

downward toward the mandibular foramen on the

medial aspect of the mandibular ramus

Locate the injection site as follows: place the thumb ofthe noninjecting hand in the coronoid notch of theramus of the mandible, simultaneously retracting thesoft tissues of the b uccal m ucosa a nd the lip (Figure 35-14)

An imaginary line extends from the midline of thethumbnail posteriorly toward the pterygomandibularraphe, a mucosal deflection running vertically with theramus of the mandible (Figure 35-15) The point at whichthe imaginary line bisects the pterygomandibular raphe isthe injection point Always approach the injection pointfrom the opposite premolars

Inject a small amount of topical anesthetic at theinjection point Approach the injection point from theopposite premolars Advance keeping the needle parallel

to the occlusal surface of the lower molars The needle

is advanced slowly through the mucosa until the bone

of the man dibular sulcus is con tacted (Figu re 35-16 ).Failure to contact bone usually is secondary to posteriorplacement of the needle behind the ramus Followingbone contact, the needle is slightly retracted and, afteraspiration, 1–3 cc of anesthetic is injected

Figure 35-12 Insertion of needle and topical anesthesia for the nasopalatine block This figure was

published in Malamed S Handbook of local anesthesia, 5th edn Copyright Elsevier 1997.

Figure 35-11 Distribution of anesthesia for the nasopalatine

nerve block This figure was published in Malamed S Handbook

of local anesthesia, 5th edn Copyright Elsevier 1997.

246 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient

Figure 35-15 Location of pterygomandibular raphe for inferior alveolar nerve block This figure was

published in Malamed S Handbook of local anesthesia, 5th edn Copyright Elsevier 1997.

Figure 35-16 Insertion of needle for inferior alveolar nerve block Reproduced with permission from

Kip Benko.

248 Topical, Local, and Regional Anesthesia Approach to the Emergency Patient