presenter: dr. james supervisor: dr. shareena

Presenter: Dr. JamesSupervisor: Dr. Shareena

Standard Monitoring

in Anaesthesia

OLD IS

GOLD!!

Monitoring: A Definition

• ... interpret available clinical data to help recognize present or future mishaps or unfavorable system conditions

• ... not restricted to anesthesia (change “clinical data” above to “system data” to apply to aircraft and nuclear power plants)

Aim?

What do you mean by that ?

• Safety of the Anaesthetist ?

• Safety of the Surgeon ?

• Safety of the Patient ?

Where Safety Starts ?

Patient

Facilities, Equipment, and Medications Anaesthetist’s Skill

Surgeon’s Skill

Survival Depends.......

Facilities, Equipment, and Medications Quantity and Quality

Anaesthetist Skill

HELP

Referal

10%

20%

60%

10%

Where Safety Starts ?

Patient - Optimized patient (CVS, RS, Renal, Liver)

- ASA risk - Well controlled Hypertension - Well controlled Diabetes - Haemodynamically stabilised

Medication• All drugs should be clearly labelled

• The label on both ampoule and syringe should be read carefully before the drug is drawn up or injected

• Ideally drugs should be drawn up and labelled by the anaesthetist who administers them.

Anaesthetist Skill• Learn one or two alternate method of Airway

skill• Practice it in routine cases

• Anaesthesia does not deliver any direct therapeutic benefit.

• The risks of anaesthesia must therefore be as low as possible.

• Anesthesiology has been identified as a leader in improving patient safety

• end of the 19th century, 1/900 patients died• late 1950s, 3.1/10 000 to 6.4/10 000 died• Last 3 decades, 0.04–7 per 10 000 died

Haller G. et al (2011)

Anaesthesia-related mortality

• Minor morbidity: – Moderate distress without prolongation of hospital stay or

permanent sequelae (e.g., postoperative nausea and vomiting (PONV)

• Intermediate morbidity: – Serious distress or prolongation of hospital stay, or both, without

permanent sequelae (e.g., dental injury).

• Major morbidity: – Permanent disability and sequelae (e.g., spinal cord injury).

Anaesthesia-related morbidity

• Suboptimal care related to inadequate patient evaluation or incorrect preoperative management, has been found to be a major contributing factor in 38–42% of deaths.

Gibbs N et al (2005), Lienhart A et al (2006)

Causes of mortality and morbidity

• Postoperative respiratory depression, suboptimal management of postoperative blood loss, insufficient supervision or inadequate resuscitation still contribute to 43% of anaesthesia-related deaths.

Lienhart A et al (2006)

Causes of mortality and morbidity

• Human error/failures– 51–77% of anaesthesia-related deaths– lack of experience or competence , 89%– errors of judgement or analysis, 11%– fatigue

Lienhart A et al (2006)

Causes of mortality and morbidity

Peri-anaesthetic care and monitoring standards

• Pre-anaesthetic care• Pre-anaesthesia checks• Monitoring during anaesthesia

Pre-anaesthesia checksPRE ANAESTHETIC CHECK LIST Patient name ________________ Number ___________ Date of Birth __/__/__Procedure____________________________________ Site_______

Check patient risk factors(if yes - circle and annotate)

Check resources Present and Functioning

ASA 1 2 3 4 5 EAirwayMallampati (pictures)Aspiration risk?Allergies?Abnormal investigations?Medications?Co-morbidities?

NNNNN

Airway Masks Airways Laryngoscopes (working) Tubes BougiesBreathing Leaks (a FGF of 300 ml/minute maintains a pressure of > 30 cm H2O)

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Check patient risk factors(if yes - circle and annotate)

Check resources Present and Functioning

ASA 1 2 3 4 5 EAirwayMallampati (pictures)Aspiration risk?Allergies?Abnormal investigations?Medications?Co-morbidities?

Soda lime (colour - if present) Circle system (2-bag test if present)SuctionDrugs and Devices Oxygen cylinder (full and off) Vaporisers (full and seated) Drips (IV secure) Drugs (lebeled - TIVA connected) Blood / fluids available Monitors - alarms on Humidifiers, warmers and thermometersEmergency Assistant Adrenaline Suxamethonium Self inflating bag Tilting table

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Level of monitoring

• Routine / Specialize / Extensive• Non-equipment / Non-invasive / Minimally invasive / Penetrating / Invasive / Highly invasive• Systematic– Respiratory / Cardiovascular / Temperature/Fetal– Neurological / Neuro-muscular / Volume status & Renal

• Standards for basic intraoperative monitoring ( ASA)

Standards for basic intraoperative monitoring

( ASA : American Society of Anesthesiologists)

Standard I – Qualified anesthesia personnel shall be present in the

room throughout the conduct of all GA, RA, MAC

Standard II – During all anesthetics, the patient’s respiratory

(ventilation, oxygenation), circulation and temperature shall be continually evaluated

Monitoring in the Past

• Visual monitoring of respiration and overall clinical appearance

• Finger on pulse• Blood pressure

(sometimes)

Monitoring in the Past

Finger on the pulse

Harvey Cushing Not just a famous neurosurgeon …

but the father of anesthesia monitoring

• 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 )

Monitoring during anaesthesia

• Oxygenation• Airway and ventilation• Circulation • Temperature• Neuromuscular function• Depth of anaesthesia• Audible signals and alarms

Examples of Multiparameter Patient Monitors

Some Specialized Patient Monitors

Depth of Anesthesia Monitor

Evoked Potential Monitor

Transesophageal Echocardiography

HIGHLY RECOMMENDED

RECOMMENDED SUGGESTED

Oxygenation Oxygen supply :

Oxygenation of the patient :

- Supplemental oxygen -Un interrupted supply

- Visual examination, - Adequate illumination - Pulse oximetry

- Inspired oxygen concentration - Oxygen supply failure alarm -Hypoxic Guard

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Airway and ventilation

- Observation - Auscultation - The reservoir bag -Capnography

- Precordial, - Pretracheal, or -Oesophageal stethoscope

- Continuous measurement of the inspiratory and/or expired gas volumes, and of the concentration of volatile agents

Circulation Cardiac rate and rhythm :

Tissue perfusion :

Blood pressure :

-Palpation of the pulse - Auscultation of the heart sounds - Pulse oximetry

- Clinical examination- Pulse oximetry

- At least every 5 mts

- Electrocardiograph- Defibrillator

- Capnography

- NIBP - IABP

HIGHLY RECOMMENDED RECOMMENDED SUGGESTED

Temperature - At frequent intervals

- Continual electronic temperature measurement

Neuromuscular function

- Peripheral nerve stimulator

Depth of anaesthesia - Degree of unconsciousness (clinical observation)

- Continuous measurement of the inspiratory and/or expired gas volumes, and of the concentration of volatile agents

- BIS Monitor

Audible signals and alarms

Available audible signals (pulse tone of the pulse oximeter) and audible alarms (with appropriately set limit values) should be activated at all times and loud enough to be heard throughout the operating room

1.1 ALL ANAESTHETICS SHOULD BE ADMINISTERED BY A REGISTERED MEDICAL PRACTITIONER WHO HAS RECEIVED SUFFICIENT TRAINING IN ANAESTHESIOLOGY AND RESUSCITATION. 1.2 SKILLED ASSISTANCE FOR THE ANAESTHESIOLOGIST MUST BE AVAILABLE AT ALL TIMES DURING THE CONDUCT OF THE ANAESTHESIA. 1.3 PROFESSIONAL CARE OF THE PATIENT DURING ANAESTHESIA REQUIRES THE CONTINOUS PRESENCE OF THE ANAESTHESIOLOGIST THROUGHOUT THE ANAESTHETIC. THE PRESENCE OF A SKILLED ASSISTANT IS NO SUBSTITUTE FOR THE ANAESTHETIST. 1.4 THE ANAESTHESIOLOGIST MUST PROVIDE AN ADEQUATE AND LEGIBLE RECORD OF THE ANESTHETIC AND THIS MUST BE PART OF THE PATIENTS MEDICAL RECORDS. 1.5 IT IS THE RESPONSIBILITY OF THE ANAESTHESIOLOGIST TO ENSURE THAT ALL EQUIPMENT USED FOR THE ADMINISTRATION OF ANAESTHESIA IS CORRECTLY FUNCTIONING BEFORE THE START OF EACH ANAESTHETIC.

I. Clinical Monitoring by an Anaesthesist

RECOMMENDATIONS

2.1 OXYGEN ANALYSER

2.2 BREATHING SYSTEM DISCONNECTION OR VENTILATOR FAILURE ALARM

2.3 PULSE OXIMETER

2.4 ELECTROCARDIOGRAPH

2.5 INTERMITTENT NON-INVASIVE BLOOD PRESSURE MONITOR

2.6 CARBON DIOXIDE MONITOR

2.7 VOLATILE ANAESTHETIC AGENT CONCENTRATION MONITOR

2.8 TEMPERATURE MONITOR

2.9 CONTINUOUS INVASIVE BLOOD PRESSURE MONITOR

2.10 NEUROMUSCULAR FUNCTION MONITOR

2.11 MONITORING OF ANAESTHETIC EFFECT ON THE BRAIN

2.12 OTHER EQUIPMENT

II. Monitoring Equipment

Cardiovascular monitoring

• Routine monitoring– Cardiac activity– Non-invasive blood pressure ( NIBP )– Electrocardiography ( ECG )

• Advanced monitoring– Direct arterial blood pressure– Cardiac filling pressure monitor• Central venous pressure• Pulmonary capillary wedge pressure

Cardiovascular monitoring

• Electrocardiography– Cardiac activity– Arrhythmia: Lead II– Myocardial ischemia– Electrolyte imbalance– Pacemaker function

Cardiovascular monitoring

• Non-invasive blood pressure (NIBP)– Cuff: width 120-150 % limb diameter, air bladder includes more

than halfway around limb– Manometer: aneroid, mercury– Detector: manual, automated

Cardiovascular monitoring• Non-invasive blood pressure– Inaccurate: cuff size, inflated pressure, shivering,

cardiac arrhythmia, severe vasoconstriction

Proper application Narrow cuff Loose cuff

Cardiovascular monitoring• Direct arterial pressure monitor– Indications• Continuous blood pressure monitor:

anticipated cardiovascular instability, direct manipulation of cardiovascular system, inability to accurate measurement directly• Frequent arterial blood sampling: ABG, Acid-

base / electrolyte / glucose disturbance, Coagulopathies

Cardiovascular monitoring• Direct arterial pressure monitor– Contraindications• Local infection• Impaired blood circulation: Raynaud’s

phenomenon, DM• Risks of thrombosis: hyperlipidemia, previous

brachial artery cannulation

• Modified Allen’s test ???

Cardiovascular monitoring• Direct arterial pressure monitor– Complications• Direct trauma: AV-fistula, Aneurysm• Hematoma• Infections• Thrombosis• Embolization• Massive blood loss

Respiratory monitoring• Ventilatory monitoring• Oxygenation monitoring• Machine and Circuit monitoring– Clinical skills– Monitoring devices

Ventilatory monitoring• Clinical skills– Direct observation: rate, rhythm, volume of respiration– Auscultation: precordial, esophageal stethoscope– Palpation: reservoir bag movement

• Monitoring devices– Spirometer– Airway pressure manometer– Circuit disconnection alarm

Ventilatory monitoring

• Capnometer (End-tidal CO2 analysis)

– relationship with PaCO2 : ETCO2 < PaCO2 ~ 3-6 mmHg

– mainly depends on dead space ventilation– normal value 30 – 35 mmHg– Infrared absorption spectrography– Main-stream VS. Side-stream

Ventilatory monitoring• Capnogram : normal curve– 1. Dead space air (no CO2)

– 2. Mixed bronchus & alveolus air (CO2 upstroke)

– 3. Alveolus air (CO2 plateau)Inspiration

ETCO2

12

3

Ventilatory monitoring

• Capnometer (End-tidal CO2 analysis)– Most useful in detection of Esophageal intubation,

airway or circuit disconnection

– Useful in CO2 rebreathing, partial recovery of neuro-muscular blockade, good predictor of successful CPR

waveform of ET-CO2

• Capnograph-esophageal intubation-bronchial intubation-airway obstruction-circuit disconnect-circuit leakage-partial rebreathing-spontaneous breathing (recovary of neuromuscular blockade)-hypoventilation

Oxygenation monitoring• Clinical skills– Direct observation: impaired mental function,

sympathetic overactivities, appearance(+ cyanosis)– Auscultation: wheezing, crepitation

• Monitoring devices– Arterial blood gas analysis

– Percutaneous O2 measurement

– Pulse oximeter

Oxygenation monitoring• Pulse oximeter– SpO2 correlates with PaO2

as in Oxygen-hemoglobin dissociation curve

– SpO2 90 = PaO2 60 mmHg

(moderate hypoxemia)

Oxygenation monitoring• Pulse oximeter artifacts– Abnormal hemoglobin: COHb, MetHb, HbF– Dye: Methylene blue– Anemia– Ambient light– Arterial saturation– Blood flow– Motion– Nail polish– Electro-cautery

Machine & circuit monitoring

• Safety system– DISS, PISS, Quick disconnection adaptor– Oxygen fail-safe valve, Oxygen supply failure alarm

• Oxygen analyzer• Airway gas composition– Clinical skills: flowmeters, vaporizers– Monitoring devices: Infrared spectrometer

Depth of Anesthesia • Clinical Signs

– eye signs

– respiratory signs

– cardiovascular signs

– CNS signs

• EEG monitoring

• Facial EMG monitoring (experimental)

• Esophageal contractility (obsolete)

Neurologic monitoring

– Depth of anesthesia ( BIS )– EEG– Evoked potentials– Cerebral blood flow– Intracranial pressure

Neuromuscular monitoring

– Clinical skills– Monitoring device :

Volume status and renal monitoring

– Estimate blood loss– Urine output– Hemodynamic stability

Electrolyte / Metabolic monitoring

• Fluid balance• Sugar• Electrolytes• Acid-base balance

Temperature monitoring

– 4 mechanism of heat loss– Perioperative hypothermia (BT<36)– Core temperature : nasopharynx, esophageal,

tympanic membrane, pulmonary a. catheter, bladder, rectum

Temperature Monitoring

Rationale for use• detect/prevent hypothermia• monitor deliberate hypothermia • adjunct to diagnosing MH• monitoring CPB cooling/rewarming

Temperature monitoring

– Deleterious effects of hypothermia -cardiac dysrhythmia -increased PVR -Lt. shift of the Oxygen-hemoglobin dissociation curve -reversible coagulopathy (platelet dysfunction) -postoperative protein catabolism and stress response -altered mental status -impaired renal function -decreased drug metabolism -poor wound healing

• Vigilance in OT cannot be over-emphasized• Technology does not guarantee safety and accuracy• Monitor with purpose• Record and Communicate the findings• Respond to findings

CONCLUSION

Thank you