Mazen Kherallah, MD, FCCPCritical Care Medicine and

Infectious Disease

Visual monitoring of respiration and overall clinical appearance

Finger on pulse Blood pressure

(sometimes)

Invented and popularized the anesthetic chart

Recorded both BP and HR

Emphasized the relationship between vital signs and neurosurgical events ( increased intracranial pressure leads to hypertension and bradycardia )

Standardized basic monitoring requirements (guidelines) from the ASA (American Society of Anesthesiologists), CAS (Canadian Anesthesiologists’ Society) and other national societies

Many integrated monitors available Many special purpose monitors available Many problems with existing monitors

(e.g., cost, complexity, reliability, artifacts)

Manual blood pressure cuffFinger on the pulse and foreheadMonaural stethoscope

(heart and breath sounds)Eye on the rebreathing bag

(spontaneously breathing patient)Watch respiratory patternWatch for undesired movementsLook at the patient’s face

color OK? diaphoresis present? pupils

Examples of Multiparameter Patient MonitorsExamples of Multiparameter Patient Monitors

Transesophageal EchocardiographyDepth of Sedation

Monitor

Correct ETT placement ETT cuff pressure Suctioning Oxygenation Ventilation Airway pressure Airway gas monitoring Clinical: wheezing, crackles, equal air

entry, color, respiratory pattern (rate, rhythm, depth, etc.)

Purpul Yellow

3-4 cm

Secure ET tube in place, note the numberSedate patient with appropriate MAASAvoid accidental, or self extubation

These include bedside sphygmomanometers, special aneroid cuff manometers, and electronic cuff pressure devices.

Ideally, most tubes seal at pressures between 14 and 20 mm Hg (19 to 27 cm H2O).

Tracheal capillary pressure lies between 20 and 30 mm Hg

Impairment in tracheal blood flow seen at 22 mm Hg and total obstruction seen at 37 mm Hg

Air inflation of the tube cuff until the airflow heard escaping around the cuff during positive pressure breath ceases.

Place a stethoscope over larynx. Indirectly assesses inflation of cuff.

Slowly withdraw air (in 0.1-mL increments) until a small leak is heard on inspiration.

Remove syringe tip, check inflation of pilot balloon

What is the amount of light absorbed by the “peak” of the cardiac cycle

Patient conditionsCarboxyhemoglobin

Erroneously high reading may presentAnemia

Values as low as 5 g/dl may result in 100% SpO2Hypovolemia/Hypotension:

May not have adequate perfusion to be detected by oximetry

Hypothermia: peripheral vasoconstriction may prevent

oximetry detection

Ambient Light Any external light exposure to capillary bed

where sampling is occurring may result in an erroneous reading

Excessive Motion Always compare the palpable pulse rate with

the pulse rate indicated on the pulse oximetry Fingernail polish and pressed on nails

Most commonly use nails and fingernail polish will not affect pulse oximetry accuracy

Some shades of blue, black and green may affect accuracy (remove with acetone pad)

Skin pigmentation Apply sensor to the fingertips of darkly

pigmented patients

Coarse breath sounds Noisy breathing Visible secretions in the airway Decreased SpO2 in the pulse oximeter &

deterioration of arterial blood gas values Clinically increased work of breathing Suspected aspiration of gastric or upper

airway secretions Changes in monitored flow/pressure

graphics Increased PIP; decreased Vt during

ventilation

Open SuctioningDisconnection from the ventilatorNot recommended when PEEP >10

Closed Suctioning:Facilitate continuous mechanical ventilation and oxygenation during the suctioning.Indicated when PEEP level above 10cmH2O

Fever Sepsis Hyperthyroidism Agitation Overfeeding

Static properties: Inspiration holdStatic properties: Inspiration hold

CC

Plateau pressure 3030

30

3030

30

30

30

Airway resistance

Pressure

Time

1 Sec. Lung compliance

time

Pressure

PEEP

PIP

PplatAlveolar Distending (recoil) Pressure difference (Pdis)

Flow-Resistive Pressure difference (Pres)

Peak Inspiratory Pressure

Plateau Pressure

High PIP

Normal PPlat

Problem ManagementKinked endotracheal tube Adjust positionPatient’s biting on the ETT SedateExcessive Secretions SuctioningBlocked endotracheal tube ChangeBronchospasm Bronchodilator

High PIP

High PPlat

Pneumothorax Hemothorax Pleural effusion Pneumonia Congestive heart failure ARDS

Persistent Flow

Auto PEEP: Dynamic Hyperinflation

Management:Decrease Tidal VolumeDecrease Insp/Exp ratio

Increase inspiratory flowDecrease rateDecrease Inspiratory time

System leak: Gurgling sound in the neck areaDislodged ETTDeflated cuffPunctured cuff

Bronchopleural fistula: Gurgling sound in the chest area

Secure your ETT and avoid accidental or self extubation

Will monitor your cuff pressure to avoid tracheal wall pressure injury

Suction you with closed system Set ventilator alarms to detect

variations early Elevate the head of bed to > 30º Use deep venous thrombosis

prophylaxis when indicated Use Stress ulcer prophylaxis

Mazen Kherallah, MD, FCCPCritical Care Medicine and

Infectious Disease