CRITERIA FOR EXTUBATION

Dr. Devi priyaMd2

ROUTINE EXTUBATION-Operating Room:

-RETURN OF CONCSIOUSNESS AND SPONTANEOUS RESPIRATION

-RESOLUTION OF NEUROMUSCULAR BLOCKADE

-ABILITY TO FOLLOW SIMPLE COMMANDS

SUBJECTIVE:

-FOLLOWS COMMANDS

-CLEAR OROPHARYNX/HYPOPHARYNX( BLEEDING,SECRETIONS)

-INTACT GAG REFLEX

-SUSTAINED HEAD LIFT FOR 5 SECS,HAND GRASP

-ADEQUATE ANALGESIA

OBJECTIVE

CLINICAL:

● CARDIOVASCULAR AND HEMODYNAMIC STABILITY

● ABSENCE OF EXCESSIVE SECRETIONS

● NORMOTHERMIA

● APPOROPRIATE ACID-BASE STATUS

VENTILATORY CRITERIA:

● PaCO2< 50 mm hg

● Vital capacity > 10 ml /kg

● Spontaneous tidal volume > 5 ml/kg

● Spontaneous RR <30 / mt

● Minute ventilation < 10L/ min with satisfactory ABG

● Max insp. Pressure > -30 CM H20 in 20 secs

OXYGENATION CRITERIA:

-Pao2 >60 mm hg

FULL REVERSAL OF MUSCLE RELAXATION:

T4/ T1 RATIO >0.9

SUSTAINED TETANIC CONTRACTION> 5 SECS

ICU SETTING:

SUBJECTIVE:

● Underlying disease process improving

OBJECTIVE:

● GCS>13

● Pao2 without PEEP : - >60 mm hg at Fio2 upto 0.4

● With PEEP - > 100 mm hg at fio2 upto 0.4

● Sao2 >90% at fio2 of 0.4

● ALVEOLAR- ARTERIAL O2 tension GRADIENT :(FIO2 1.0) <350 mm hg

For every 50 mm hg difference, shunt percent is 2%

● DEAD SPACE TO TIDAL VOLUME RATIO : < 0.6

PaCO2-PeCO2/ PaCO2

● Horowitz index for lung function (P/F) > 150 mm hg

● RAPID SHALLOW BREATHING INDEX < 100 breaths/min/L

● SPONTANEOUS BREATHING TRIAL

● Airway resistance - suction/ bronchodilator

SPONTANEOUS BREATHING TRIAL :

● May use T tube,CPAP, OR low level pressure support

● Automatic tube compensation- “electronic extubation”

● Let patient breathe for 30 mins spont

Assess patient

● If patient tolerates- normal resp pattern,adeqaute gas exchange-consider

extubation when blood gases and vital signs are satisfactory.

EXTUBATION PROTOCOL:

4 P’s -

Plan- low risk / high risk

Prepare-patient factors/ monitoring/equipments/assistance/extubation check list

Perform

Post extubation care

SITUATIONS PRESENTING INCREASED RISK FOR COMPLICATIONS AT

EXTUBATION:● Tracheomalacia

● Certain surgeries- thyroid,uvulopalatoplasty,cervical vertebrae

decompression,carotid endareterectomy, maxillofacial surgeries

● OSAS

● Hypoventilation syndromes-polio/GBS/MG/morbid obesity/severe COPD

● Hypoxemic syndromes- v/q mismatch,intracardiac/pulmonary shunting,severe

anemia etc

● Generalized edema, anaphylaxis.

-Patient position- supine/semi upright/ lateral/ prone

-Timing of extubation

-Bite blocks

Awake vs deep - assess the relative risk of aspiration vs coughing / straining vs UAO

AWAKE EXTUBATION:

DEFINITION:”tracheal extubation after appropriate response to verbal stimuli with recovery of protective airway reflexes”

● 100% oxygen● Suction adequate● Bite block● Position appropriately● Antagonise NMB● Regular adeq spontaneous breathing● Wait until awake,obeying ● Positive pressure,deflate cuff● extubate● Check airway patency,adeq breathing● Continue o2 supplement

DEEP EXTUBATION:

Definition- “tracheal extubation in spontaneously breathing patients under the absence

of any protective respiratory reflexes”

● Ensure there is no surgical stimulation

● Adequate analgesia

● 100% oxygen

● Ensure adequate depth of anesthesia

● Antagonize NMB

● REMOVE SECRETIONS ,IDEALLY UNDER DIRECT VISION

● Deflate cuff ,apply positive pressure,extubate

● Maintain airway patency until pt is fully awake

● Continue oxygen until recovery is complete

COMPLICATIONS DURING AND POST TRACHEAL EXTUBATION:

-Cardiovascular response

Dexmed infusion 1mcg/ kg 10 mins prior

fentanyl infusion 1 mcg/kg 10 mins prior

Magnesium 40 mg/kg 5 mins before extubation

lidocaine 1mg/kg over 2 mins

esmolol 0.5 mg/kg an be used 2 mins prior to extubation

- Increased pressures- ICP/IAP/IOP

- Risk of surgical complications

APPROACH TO DIFFICULT EXTUBATION:

PREPARATION OF STANDBY EQUIPMENTS FOR RE INTUBATION

POST EXTUBATION AIRWAY COMPETENCY: cuff leak test- doubtful on the reliability

Steroids

EXCHANGING A LARYNGEAL MASK

EXTUBATION OVER A FLEXIBLE BRONCHOSCOPE

AIRWAY EXCHANGE CATHETERS CAN ALSO BE USED

Aintree intubation catheter

Airway exchange catheter

A patient post cervical spine fusion, with

AEC in situ.

Conclusion

- Judgement on timing of extubation depends on patient factors, surgical factors and

anesthetists preference.

- The anesthetist must evaluate every patient in terms of potential for problems

during extubation in the same manner that he prepares for an unanticipated

difficult airway. !

Thank you!