• anesthesia:lack of sensation/perception

DifScilt MaskVeatiiatioa

toothAic!g200S:1K|6!:187(Ma0

P urpose:Densrjprtiddifksflnask

radiation.

Conclusions:Age »55.obesity«tEIC >2S.tistiiry

ofsnnrcg.tiffin).at

*

ofSett Mallaupeti lt.Pf (see

f

^

aref.AJLatinonra: nanditisiarprotiaxKtasL

end male gender era at mdeoendes risk feesis

restartteused es jredcisfodSct cask

radiation.

Preoperative Preoperative/Intraoperative Postoperative

3. Plan anesthetic

4. Re-medication

5. Airway management

6. Monitors

7. Induction

8. Maintenance

9. Emergence

10.Tracheal extubation

1. Preoperative assessment

2. Patient optimization

11.Postoperative care

Preoperative Assessment E

Purpose

• identify concerns for medical and surgical management of patient

• allow for questions to help allay any fears or concerns patient and/or family may have

• arrange further investigations, consultations, and treatments for patients not yet optimized

• plan and consent for anesthetic techniques

History and Physical

History

• age and gender

• indication for surgery

• surgical/anesthetic Hx: previous anesthetics, any complications, previous intubations, and PONV

• I MHx:abnormal anesthetic reactions, MH,and pseudocholinesterase deficiency (see Uncommon

Complications, A29)

• medications and allergies (see PreoperativeOptimization: Medications, A-/)

• PMHx

neuro:seizures, TIA/strokes, raised ICP,spinal disease, aneurysm, and conditions affecting NM|

(e.g.myasthenia gravis)

CVS:angina/CAD, Ml, CHI'

, HTN,valvular disease, dysrhythmias, PVD, conditions requiring

endocarditis prophylaxis, exercise tolerance, and CCS/NYHA class (seeCardiology and

Cardiac Surgery sidebar for CCS Classification, C31and sidebarfor Mew York Heart Association

Classification, C41)

respiratory:smoking, asthma, COPD, recent URT I, and sleep apnea

Cil:CitRD, liver disease, and N PC)status

renal: acute vs. chronic renal insufficiency, dialysis, and chronic kidney disease

• hematologic: anemia, coagulopathies, and blood dyscrasias

+

A3 Anesthesia Toronto Notes 2023

• \1SK:arthritis(e.g.rheumatoid arthritis,scleroderma), cervical spine pathology (e.g. cervical

tumours,cervical infections/abscesses, trauma to cervical spine, and previous cervical spine

surgery), and cervical spine instability (e.g. trisomy 21)

• endocrine: DM, thyroid disorders, and adrenal disorders

other morbid obesity, pregnancy,and ethanol/recreational drug use

Physical Exam

• weight, height, BP,HR,respiratory rate, and Oa saturation

• focused physical exam of the CNS,CVS, and respiratory systems

• general assessment of nutrition,hydration, and mentalstatus

• airway assessment is done to determine intubation difficulty (no single test isspecificorsensitive) and

ventilation difficulty

cervical spine stability and neck movement- upper cervicalspine extension,lower cervicalspine

flexion (“sniffing”

position -see Figure6C, A8)

Mallampati classification (see Figure 1 )

“3-3-2 rule’(see Figure 2)

3of patients own fingers can be placed between the incisors (incisor distance)

3fingers along the floor of the mandible between the mentum and hyoid bone (hyoid-mental

distance)

2 fingers in the superior laryngeal notch (thyroid-hyoid distance)

thvromental distance (distance from the mentum to the thyroid notch in midline with neck

extended); <3 finger breadths (<6 cm) is associated with difficult intubation

anterior jaw subluxation;<1 finger breadth is associated with difficult intubation

• tongue size

• dentition, dental appliances/prosthetic caps, existing chipped/ loose teeth - pose aspiration risk if

dislodged and patientsshould be informed of rare possibility of damage

• nasal passage patency (if planning nasotracheal intubation)

• assess potential for difficult ventilation

• examination of anatomical sites relevant to lines and blocks

bony landmarks and suitability'of anatomy for regional anesthesia (if relevant)

sites for 1V,CVP, and PA catheters

Evaluation

*

of Difficult Airway

LEMON

Look -obesity, beard, dental/facial

abnormalities, neck, facial/neck trauma

Evaluate -3-3-2 rule

Mallampatiscore (>3)

Obstruction -stridor,foreign bodies.

masses

Neck mobility

§< >

Assessment of Difficult Ventilation

Anesthesiology 2000:92:1229-1236

BONES

Beard

Obesity (BMI >26)

No teeth

Bderly (age >55)

Snoring Hx (sleepapnea)

3

landible

lid

Thyroid

' V cartilage

I

Fullview of Body and base

of uvula uvula ( body

- - .

-

•

- s Tonsillar pillars

and tonsils (partial view)

Tonsillar pillars

Hard palate:

III IV Otherstructures

not visible Base of uvula

\/

Tongue

a

:

f

Post-pharyngeal wall Figure 2.3-3-2 Rule

Figure 1. Mallampati classification of oral opening

Cormack-Lehane Classification of

Laryngeal View [Figure3.A4)

• Grade1:all laryngealstructures

revealed

• Grade 2:posterior laryngeal showing

posterior vocal folds and arytenoids

. Grade 3:larynx concealed, only

epiglottis

• Grade 4:neither glottis nor epiglottis

n

+

A!Anesthesia Toronto Notes 2023

Preoperative Investigations Epiglottis Vocal told

• routine preoperative investigations are only necessary if there are comorbidities or certain indications

Table 1. Suggested Indications for Specific Investigations in the Preoperative Period

Test Indications

CBC Major surgery requiring group and screen or cross and match; chronic CV, pulmonary, renal, or hepatic disease;

malignancy;known or suspected anemia; bleeding diathesis or myelosuppression;patient <1y/o

Genetically predisposed patient (hemoglobin electrophoresis ifscreen is positive)

Anticoagulant therapy, bleeding diathesis, liver disease

Sickle CellScreen

INR. aPTT

Electrolytes and Creatinine H1N,renal disease,DM, pituitary or adrenal disease;vascular disease,digoxin,diuretic, or other drug therapies

affecting electrolytes

Fasting Glucose Level

Pregnancy|p-hCG|

DM (repeat on day of surgery)

Women of reproductive age

Heart disease, DM. other risk factors for cardiac disease; subarachnoid or intracranial hemorrhage,

cerebrovascular accident, head trauma

©Arisen Lin 2019 ECG

Figure 3. Laryngeal views

exit Patients with new or worsening respiratory symplomslsigns

Guidelines to thePractice ot Anesthesia RevisedEdition 2013.Supplement to the Canadian Journal of Anesthesia,Val GO.Dec. 2013.Reproduced

with permission CanadianAnesthesiologists'Society

American Society of Anesthesiology Classification

Continuation vs.Discontinuationof Antiplatelet

Therapy for Bleeding and Ischaemic Events in

A dults Undergoing Kon-Cardiac Surgery

Cochrane OB Syst Rev 2018;C0012584

Purpose: fo compare the effect of continuation

vs.discontinuation of antiplatelet therapyon the

occurrence of bleeding and ischaemic events in adults

undergoing non-cardiac surgery.

Methods: RCTsm Cochrane Central Register

of Controlled trials,MEDLINE, and Embase that

compared adults taking single or dual antiplatelet

therapy for alleast two weeks, including patients

with at least one cardiac nsk factor. Included general,

spmal.and reg onal anesthesia and excluded minor

procedures involving only local anesthetio'sedation.

Results: 5 trials.

(6$ adult patients.Co -tinnation or

discontinuation had no difference on mortality at 30

d postoperative (RR 1.21,95T> Cl 0.34-4.22).blood

loss (RR 1.37, 55% Cl 0.83 2.26|. or ischaemic events

within 30 d of surgery(RR 0.62. 85% Cl0.25-1.221.

Conclusions:Moderate evdonee supporting

continuation or discontinuation ol antiplatelet

therapy makesno difference on bleeding requiring

transfusion,low evidence supporting no difference nr

mortality or Isthaemicevents.

• common classification of physical status at the time of surgery

• a gross predictor of overall outcome, NOT used as stratification for anesthetic risk (mortality rates)

• ASA 1; a healthy, fit patient

• ASA 2: a patient with mild systemic disease

• e.g. controlled T2DM, controlled essential HTN, obesity,smoker

• ASA 3: a patient with severe systemic disease that limits activity

e.g.stable CAD,COPD, DM, obesity

• ASA -i: a patient with incapacitating disease that is a constant threat to life

e.g. unstable CAD, renal failure, acute respiratory failure

• ASA 5: a moribund patient not expected to survive 24 h without surgery

e.g. ruptured abdominal aortic aneurysm (AAA ), head trauma with increased ICP

• ASA 6:declared brain dead, a patient whose organs are being removed for donation purposes

• for emergency operations, add the letter 1:after classification (e.g. ASA 3E)

Preoperative Optimization

• in general,prior to elective surgery:

any fluid and/or electrolyte imbalance should be corrected

extent of existing comorbidities should be understood and these conditions should be optimized

prior to surgery

• medications may need adjustment

Medications Integration olthe Duke Activity Status Index into

Preoperalive Risk Evaluation

8 iJAnatsth 2020;t24|3):261 220

Purpose: Duke AcMy Status Index (DASI)

questionnaire could be integratedinto preoperalive

risk assessment.

Methods: Nested cohort analysisol the Measu'emenl

of Exercise tolerance (MEIS) study lo characterise

association ol preoperative DASI scoreswith

postoperative deaths and complications. Analysis

included 1546 patients >40 y/o at elevatedcardiac

risk that hadinpatient non-cardiac surgery.

Results: Results were non-lmear but threshold was

lound. Sell-reported functional capacity heller than

a DASI score ol 34 was associated with reduced odds

ol 30 d death or Ml(OR:0.92 perIpoint Increase

above 34:95% Cl:0.96 0.99) and 1yr death or new

disunity (OR : 0.96 per 1pentincrease above 34;

95% Cl: 0.92-0.99).

Conclusion:A DASI score ol 34 represents a threshotf

lor identifying patients atrisk lor myocardial m.ury.

Ml. nroderale-to-severe complications,and new

disability.

• pay particular attention to cardiac and respiratory medications, opioids, and drugs with many side

effects and interactions

• preoperative medications to consider as prophylaxis

risk of Cili rellux: antacids (e.g. sodium citrate), H2 antagonists and/or prokinetic agents (e.g.

metoclopramide) 0.5- 1 h prior to surgery

• risk ofinfective endocarditis, GI/

(iU interventions: antibiotics

• risk of adrenal suppression: steroid coverage

anxiety: consider benzodiazepines

• COED,asthma:bronchodilators

• CAD risk factors: nitroglycerin and p-blockers

• preoperative medications to stop prior to surgery

• oral antihyperglycemics: do not take on the day of surgery

angiotensin-converting enzyme inhibitors (ACE1) and angiotensin receptor blockers ( ARB):

do not take on the day of surgery (controversial - they increase the risk of hypotension postinduction but have not been shown to increase mortality or adverse outcomes; therefore, some

people hold and some do not)

warfarin (consider bridging with heparin),antiplatelet agents (e.g. dopidogrel), Xa inhibitor,

direct thrombin inhibitors

discuss perioperative use of ASA and NSAIDs with surgeon (± patient’s cardiologist/internist)

+

A5 Anesthesia TorontoNotes 2023

for patients undergoing non-cardiac surgery,starting or continuing low-dose ASA in the

perioperative period does not appear to protect against postoperative MI or death, but

increasesthe risk of major bleeding

note: this does not apply to patients with bare metal stents or drug-eluting coronary stents

herbal supplements (e.g. ephedra,garlic,ginkgo, ginseng,kava, St. John’

s Wort, valerian,

echinacea - stop one week prior to elective surgery)

• preoperative medications to adjust

insulin (consider insulin/dextrose infusion or holding dose), prednisone, bronchodilators

Hypertension

• BP <180/110 is not an independent risk factor for perioperative cardiovascular complications

• target sBP <180 mmHg, dBP <110 mmHg

• assessfor end-organ damage and treat accordingly

Coronary Artery Disease

• ACC/AHA Guidelines (2014) recommend that at least 60 d should elapse after a Ml before non-cardiac

surgery in the absence of a coronary intervention

» this period carries an increased risk of re-infarction/death

if operative procedure is essential and cannot be delayed, then invasive intra- and postoperative

1CU monitoring is required to reduce the above risk

• mortality with perioperative Ml is 20-50%

• perioperative p-blockers

may decrease cardiac events and mortality (but increases risk of perioperative strokes)

continue P-blocker if patient is routinely taking it prior to surgery

consider initiation of P-blocker in:

patients with CAD or indication for p-blocker

intermediate or high-risk surgery', especially vascular surgery

Perioperative p-blockersfor Preventing SurgeryRelated Mortality aod Morbidity in Adults

undergoing CardiacSurgery

Cochrane OB Syst Re*

20t9;MDfl13435

Purpose:To assessthe effectiveness of

perioperathrety administered B-blockersfor the

pretention ofsurgery-related mortality and morbidity

in adults undergoing cardiac surgery.

Conclusions:No evidence of a difference in early

all-cause mortabty.MI.cerebrovascular enents.

hypotension,and bradycardia.Konever,there may be

areduction inAFAand ventricular arrhytbmias nben

8blockers are used.A largersam pie sire islikely to

increase the certainty of thisevidence.

Respiratory Diseases

• smoking

adverse effects: altered mucus secretion and clearance, decreased small airway calibre, altered 02

carrying capacity, increased airway reactivity, and altered immune response

abstain at least 4-8 wk preoperatively if possible

if unable, abstaining even 24 h preoperatively has been shown to increase O2 availability to tissues

• asthma

» preoperative management depends on degree of baseline asthma control

» increased risk ofbronchospasm from intubation

administration ofshort course (up to 1 wk) preoperative corticosteroids and inhaled p2-agonists

decreases the risk of bronchospasm and does not increase the risk of infection or delay wound

healing

avoid non-selective p-blockers due to risk ofbronchospasm (cardioselective P-blockers

(metoprolol, atenolol) do not increase risk in the short-term)

delay elective surgery for poorly controlled asthma (increased cough or sputum production,

active wheezing)

ideally, delay elective surgery by a minimum of 6 wk if patient develops URT1

• COPD

anesthesia,surgery (especially abdominal surgery and upper abdominal surgery, in particular)

and pain predispose the patient to atelectasis, bronchospasm, pneumonia, prolonged need for

mechanical ventilation, and respiratory failure

preoperative ABG is needed for all COPD stage 11 and 111 patients to assess baseline respiratory

acidosis and plan postoperative management of hypercapnia

» cancel/delay elective surgery for acute exacerbation

Perioperativep-blockersfor Preventing SurgeryRelated Mortality and Morbidity in Adults

undergoing Non-Cardiac Surgery

Cachrane 0B Syst Rev 2019:9

^

0013438

Purpose:Assess effectiveness of preoperatively

administered Jl-Mockers in prevention of surgeryrelated morbidity and mortality after non-cardiac

surgery.

Conclusions:No difference in cerebrovascular events

or ventricular arrhythmias.8- blockers may reduce

tf iband Ml.However,p-tilockersmay increase

bradycardia and probably increase hypotension.

Overall low quality and certainty evidence for these

findings.

8-blockers

• 81-receptors are located primarily in

the heart and kidneys

• 82-receptors are located in the

smooth muscle (i.e. bronchi,uterus)

. Non-selective 8-blockers block

81 and 82-receptors (labetalol*

.

carvedilol",nadolol). Caution

is required with non-selective

8-blockers,particularly in patients

with respiratory conditions where

82 blockade can result in airway

reactivity

labetaMa belli jn a- and p-Nocksi

-urrtditalIs alsobothan o- andp-btadter

Aspiration

• increased risk of aspiration with:

decreased LOG (drugs/alcohol, head injury, CNS pathology, trauma/shock)

delayed gastric emptying (non-fasted within 8 h, diabetes, narcotics)

decreased sphincter competence (GERD, hiatus hernia, nasogastric tube, pregnancy, obesity)

increased intra-abdominal pressure (pregnancy, obesity, bowel obstruction, acute abdomen)

unprotected airway (LMA mask vs. HIT)

• management

manage risk factors if possible

utilize protected airway (i.e.ETT)

reduce gastric volume and acidity

n

L J

+

A6 Anesthesia Toronto Notes 2023

• delay inhibiting airway reflexes with muscular reiaxants

employ RSI (see Rapid Sequence Induction, A16 )

Implementation of a Comprehensive Patient

Ble e d Men

Itienis a

MayoCInProc. 2021:96\12>:258C

Purpose to assess changesto itfiuooo of in pater

transfuses and the associated outcomeswith

impe-entaton ot a Patient Blood Mareagenent

Program.

Methods: As observationalstudy ns conducted

between 2010 and 2017 at a major IIS aca demic

centre.Transfusion usageandciskaioutcomes

were assessed.

Besilts:400998 admissions were assessed. Overall

usage oi rpatient transfusion decreased from 607

to 405 per 1000 admissions Also,length of stay a

hospital and in-hospital adverse events decreased.

Condnsion : Thisstudy e«h itorts that hospital- wide

patient hiood na na gemect protocolsresult in an

ovtra I decrease in transfusion sage and improved

clinics!ootroaes.

secernent Program for Hospitalized Fasting Guidelines ta large United StaiesMedical Center

Fasting Guidelines Prior to Surgery (Canadian Anesthesiologists’ Society)

• fasting guidelines should change depending on patients’

pre-existing medical conditions.In the case

of emergent procedures,consider the risk of delaying surgery against the risk of aspiration

• before elective procedures, the minimum duration of fasting should be:

• 8 h after a large meal ofsolids particularly containing protein (e.g. meat) or fatty foods

• 6 h after a light meal (e.g. non-fatty meal such as toast)

6 h after ingestion of infant formula, non-human milk, or expressed breast milk fortified with

additions

4 h after ingestion of breast milk

• 2 h after clear fluid intake (including water, pulp-free juice, complex carbohydrate beverages, and

tea or coffee without milk) for adults

• 1 h after clear fluid intake for infants and children

Hematological Disorders

• history of congenital or acquired conditions (sickle cell anemia, factor VIll deficiency, HR liver

disease)

• evaluate hemoglobin, hematocrit, and coagulation profiles when indicated (see Table 1, /14)

• anemia

• preoperative treatments to increase hemoglobin ( PC) or IV iron supplementation, erythropoietin,

or pre-admission blood collection in certain populations)

• coagulopathies

discontinue or modify anticoagulation therapies(warfarin, clopidogrel, ASA,apixaban,

dabigatran) in advance of elective surgeries

administration of reversal agents if necessary: vitamin K, FFP, prothrombin complex concentrate,

recombinant activated factor VI!

Interventions forPieoperaSvf Socking

Cessation

Ibcbrace 00 Syst Rev 2014;3TDO02294

Pnrpose:Assessthe effect of preopeiative smoking

intervention on smoking cessation at the tune of

surgery and 12 mo postope-alively,and on the

ioodecce of postoperative compLcations.

Methods:5rstematic review aclodng IICIsthat

recrated people who smoked pror to surgery, offered

a smokeg cessation mterxco:.and measured

pceoperatve and long-term ahsAneoce from smoking

or the -cdence of postoperative amplications

orML

Besilts:Thirteen trials enrol :-g 2010 participants

Inc. del Overall quality of erdeoce was moderate.

Compared studies involving mteusve intervention,

which mdoded molti-session face to face counselling

o;computer-based schedu'

ed interventions.vs.

h-ef itftrvtntions.These mere pooled separately.

An effect on cessation at the time of surgery wa s

appa-ect n both subgroups, bat the effect was larger

for intensive intervention,for long term cessation,

onlytke aansivemterveotioo snowed effect. In

thoseCat tad intensive mlervetboo there was

sjgmmcaot effect in preveoteg amy postoperative

enrapheatons.

Conclusion:There is evidencePrat preoperative

smokng interventions providing behavioural support

and o3ercg HIT increase short-term smoking

cessation and may teduce postoperative morbidity.

Intervertonsthat begin 4 to8 wk before surgery,

include weekly coimselirg.and use BIT are more

likely to have an impact on rang heatonsand longterm smoking cessation.

Endocrine Disorders

• l

)M

• clarify type 1 vs. type 2

• clarify treatment-oral anti-hyperglycemics and/or insulin

assess glucose control with history and HbAlc;patients with well-controlled diabetes have more

stable glucose levelsintraoperatively

end organ damage:be aware of damage to cardiovascular, renal, and central, peripheral, and

autonomic nervoussystems

• preoperative guidelines for DM:

• verify target blood glucose concentration with frequent glucose monitoring: <10 mmol/L in critical

patients, <7.8 mmol/L in stable patients

• use insulin therapy to maintain glycemic goals

• hold higuanides, a-glucosidase inhibitors, thiazolidinediones,sulfonylureas and GLP-1 agonists on

the morning ofsurgery

• consider cancelling non-emergency procedures if patient presents with metabolic abnormalities(e.g.

DKA, HHS, etc.) or glucose reading above 22.2-27.7 mmol/L

formulate intraoperative glucose management plan based on type (1 vs. 2), glucose control, and

extent of end organ damage

• hyperthyroidism

• can experience sudden release of thyroid hormone (i.e. thyroid storm) if not treated or wellcontrolled preoperatively

treatment:p-blockers and preoperative prophylaxis

• adrenocortical insufficiency (e.g. Addison’

s, exogenoussteroid use)

• consider intraoperative steroid supplementation

Preoperatnre Anemia and Post:perativo

Outcomes in Non-Cardiac Snrgery:A

Mtrospective Cohort Study

Lancet 2011:378:1396-1407

Purpose:Assess effect of preoperatiwanemia on 30

d postooe

-eiie morbidity and morality in patients

undergo eg major non-cardiac su-gery.

Methods:Patents undergoing major non-cardiac

surgery m2008 from theAnercan College oi

Surgeons'

national Surgical O.a hy improvement

Program database.

Besilts:227425 adult patents.Postoperative

mo-teSty et 30 d was higher m pete*

with anemia

tnan those without (081.42,95V Cl131-134).

Coodtsio*

:Preoperat ve a

_ e— a. even to a

mild degree, is independently associated with an

increased risk of 30 d morb dty a-d mortality.

Obesity and Obstructive Sleep Apnea

• assess for co-morbid conditions in obese patient (independent risk factor for CVD, DM, OSA,

cholelithiasis, HTN)

• previously undiagnosed conditions may require additional testing to characterize severity

• severity of OSA may be determined from sleep studies and prescribed pressure settings of home CPAP

device

r T

L J

+

A7 Anesthesia Toronto Notes 2023

Monitoring

Pre-Anesthetic Checklist Canadian Guidelines to the Practice of Anesthesia and Patient Monitoring

• an anesthetist present:

“the only indispensable monitor”

• a completed preanesthetic checklist:including ASA class, NPO policy, and Hx and investigations

• a perioperative anesthetic record: HR and BP every 5 min, O’

saturation, E ICO’

,dose and route of

drugs and fluids

• continuous monitoring:see Routine Monitors for y\ll Coses

Routine Monitors for All Cases

• pulse oximeter,BP monitor, ECG, capnography (required for GA and deep proceduralsedation,

Ramsay Sedation Scale 4-6), and an agent-specific anesthetic gas monitor when inhalational

anesthetic agents are used

• the following must also be available:temperature probe, peripheral nerve stimulator,stethoscope,

appropriate lighting,spirometry, and manometer to measure ETT cuff pressure

Elements to Monitor

• anesthetic depth

end-tidal inhaled anesthetic monitoring and EEG monitoring,such as a Bispectral Index monitor,

can be used as assessments of anesthetic depth

inadequate:blink reflex present when eyelashes lightly touched, HTN, tachycardia, tearing, or

sweating. However, these findings are non-specific

• excessive: hypotension, bradycardia

• oxygenation: pulse oximetry, 1

'

iOi

• ventilation: verify correct position of ETT,chest excursions,breath sounds, ETCO’

analysis, end-tidal

inhaled anesthesia analysis

• circulation:HR,rhythm, BP, telemetry, oximetry, pulmonary capillar)'wedge pressure

• temperature

• hourly urine output

MS MAIDS

Machine:connected,pressures okay,

all metres functioning, vaporizers full

Suction: connected and working

Monitor: all monitors appropriate for

the case

Airway:laryngoscope and blades. ETT,

syringe,stylet, oral and nasal airways,

tape.bag.and mask

IV:second IV set-up and ready if

needed

Drugs: case-specific drugs ready and

emergency medications in correct

location and accessible

Special equipment:OG tube. CVP

monitor, shoulder roll.etc.

Screening for OSA

Br J Anaesth 2012:108:768-775

STOP-BANG

Snoring -loud

Tiredness - day-time

Observed apnea - during sleep

Pressure- HTN

Body mass index - >35

Age - >50 y/o

Neck -large neck circumference

Gender - male

*

70—- Heart Rate TelemetrySystemic Arterial

Pressure

134 /

-65BP from

Arterial Line

Plethvsmogrwl’

|

— -

rcrvrvru-

^

j-'

QQ— Obturation 5

,

3

1%)

End Tidal COr 39"

^

ImmHg)

13-

Laryngoscope -

ETCO. biglottis

Capnograph ro

RR Respiratory Rate ST Vocal fold

04

PAW PEXP TV O. N.O ISOFLUORAXE

650 mi

I Cuneiform

cutlags

Comiculatc

cartilage

Aryepiglottic 125 1777 v

/

8

50 / 4 3 4 0 . 7 / Os-S- spred/

Expired

Isofluorane|%)

a

•::

. 45 cmll.O i

<r

'

-y

Noil > -Invasive BP Airway Pressure Tidal Volume Minute Ventilation Inspired/ N.

-0 Concentrationl%)

Expired Oi(%|

—«

u SBarbara 3iehovsky 2012

^

Figure 4. Typical anesthesia monitor Figure 5. Landmarks for intubation

Airway Management

Airway Anatomy n This Patient Be Difficult to titubate?

JJHS 2019:321:493-503

Purpose:To identify risk facas awl j-yscal undings

that predictdifficull intubaL-oe.

Methods:Systematic review cdNEDlK and EMBASE

databases.

Results: 62studies. 33S59 patients. Pnyvcal

earration findingsthat best p-fdeted a difficult

rtabat on included grede of class 3cn upper ip bite

5st|o*

er incisors cannot reach upper Sp:IS14.95%

093-221.shorter hynmena dstaxe(<3-5ion; LB

9.4.95% 4.1-101,lelrognsthia|~endCste <9cn from

a- pie of|aw to tip of chin;LI 6.0.95% Cl 3.1-111.and a

Hala

=patiscore ?3|lfi 4.1.95% Cl 3.0-5.6).

• resistance to airflow through nasal passages accounts tor approximately 2/3of total airway resistance

• pharyngeal airway extendsfrom posterior aspect of the nose to cricoid cartilage

• glottic opening:triangular space formed between the true vocal cords; narrowest segment of the

laryngeal opening in adults

• space through w hich one visualizes proper placement of the ETT

• trachea begins at the level of the thyroid cartilage, C6, and bifurcates into the right and left main

bronchi at T4-T5 (approximately the sternal angle)

ri

i

_ j

+

A8 Anesthesia Toronto Notes 2023

Methods of Supporting Airways

Equipment for Intubation 1. non-definitive airway (patent airway)

jaw thrust/chin lift

oropharyngeal and nasopharyngeal airway

bag mask ventilation

-

LMA

2. definitive airway ( patent and protected airway)

• ETT (oral or nasal)

• surgical airway (cricothyrotomv or tracheostomy)

MDSOLES

Mon itors

Drugs

Suction

Oxygen source and self inflating

bag with oropharyngeal and

nasopharyngeal airways

laryngoscope

ETT (appropriate sire and one size

smaller)

Table 2. Methods of Supporting the Airway Stylet. Syringe for tube cuff inflation

Bag and Mask IMA ETT

Advantages/

Indications

Basic

Mon-invasive

Readily available

Easy toinsert

Less airway Iraoma/untetion

than ETT

Frees up hands (vs.face mask)

Primarily used inspontaneously

ventilating patient

Indications for intubation (SPs)

Patent airway

Protects agamst aspiration

Positive pressure ventilation

Pulmonary toilet (suction)

Pharmacologic administration

during hemodynamic instability

Insertion can bedifficult

Muscle relaxant usuallyneeded

Most invasive - setCompbcotionsDuring

Laryngoxopf and Intubation./9

Supraglottic/glotfac pathology fiat would preclude

successful intubation

Medications that can be given through

the ETT

NAVEL

Naloxone

Atropine

Ventolin

Epinephrine

Lidocaine

Disadvantages/

Contraindications

Risk of aspiration if decreased Risk of gastric aspiration

IOC PPV«20 cm HiO needed

Cannot ensure airway patency Oropharyngeal,retropharyngeal

Inability to deliver precise

tidal volume

Operator fatigue

pathology or foreign body

Does not protect against

laryngospasm or gastric

aspiration A.

Oral axis I0A)

Other Facilitate airway patency

with jaw thrust and chin lift

Can use oropharyngeal /

nasopharyngeal airway

Sizing by body weight (approx.):

40-50 kg:3

50-70kg:4

70-100 kg:5

Auscultate to avoid endobronchial intubation

Sizing (approx.):

Male:8.0-9.0mm

Female:7.0-8.0mm

Paediatric UncuBed (age >2 yfo):(age/4) - 4 mm

Tongue

Epiglottis

—-Pharyngeal

JjT'

axis (PA)

Laryngeal

axisILA)

Trachea / Tracheal Esophagus Intubation

Preparing for Intubation

• failed attempts at intubation can make further attempts more difficult due to tissue trauma

• plan, prepare, and assess for potential difficulties (see Preoperative Assessment, AJ )

• ensure equipment is available and working (test ETT cuff,check laryngoscope light and suction,

machine check)

• pre-oxygenate/denitrogenate: patient breathes 100°o Ol for 3-5 min or for 4-8 vital capacity breaths

• may need to suction mouth and pharynx first

Proper Positioning for Intubation

• align the three axes (mouth, pharynx,and larynx) to allow visualization from oral cavity’to glottis

• “sniffing position”:flexion of lower C-spine (C5-C6),bow head forward, and extension of upper

C-spine at atlanto-occipital joint (Cl), nose in the air (see Figure 6Q

• contraindicated in known/suspected C-spine fracture/instability

• poor/no view of glottic opening can be remediated by anterior laryngeal pressure

• laryngoscope tip placed in the epiglottic vallecula in order to visualize cord

B.

0A

-

Figure 6.Anatomic considerations in

laryngoscopy

A. Neutral position

B. C-spine flexion

C. C-spine flexion with atlantooccipital extension

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A9 Anesthesia Toronto Notes 2023

tODMfllM

s

-

•

3

Figure 7.Sagittal view of airway with laryngoscope in vallecula

Tube Insertion m •laryngoscopy and H IT insertion can incite a significant sympathetic response via stimulation

of cranial nervesIX and X due to a “foreign body reflex” in the trachea,including tachycardia,

dysrhythmias,myocardial ischemia,increased BP,and coughing

•a malpositioned ETT is a potential hazard for the intubated patient

if too deep, may result in right endobronchial intubation,which is associated with left-sided

atelectasis and right-sided tension pneumothorax

• if too shallow, may lead to accidental extubation, vocal cord trauma,or laryngeal paralysis as a

result of pressure injury by the ETT cuff

•the tip of ETT should be located at the midpoint of the trachea at least 2 cm above the carina, and the

proximal end of the cuffshould be placed at least 2 cm below the vocal cords

•approximately 20-23 cm mark at the right corner of the mouth for men and 19-21 cm for women

Confirmation of Tracheal Placement of Endotracheal Tube

•direct

visualization of ETT passing through cords

bronchoscopic visualization of ETT in trachea

•indirect

ETCO 2 in exhaled gas measured by capnography (gold standard for confirming the ETT is in the

airway)

• auscultate for equal breath sounds bilaterally and absent breath sounds over epigastrium

bilateral chest movement,condensation of water vapour in ETT visible during exhalation, and no

abdominal distention

refilling of reservoir bag during exhalation

CXR (rarely done):only confirms the position of the tip of ETT, not itslocation in the trachea vs.

esophagus,but can confirm endobronchial intubation

•esophageal intubation suspected when:

• ETCO:zero or near zero on capnograph

abnormalsounds during assisted ventilation

impairment of chest excursion

• hypoxia/cyanosis

presence of gastric contentsin ETT

breath sounds heard when auscultating over epigastrium/left upper quadrant

• distention ofstomach/epigastrium with ventilation

Complications During Laryngoscopy and Intubation

•dental damage

•laceration flips,gums,tongue, pharynx, vallecula,esophagus)

•laryngeal trauma

•esophageal or endobronchial intubation

Differential Diagnosis of Poor Bilateral

Breath Sounds after Intubation

DOPE

Displaced ETT

Obstruction

Pneumothorax

Esophageal intubation

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