1. Monitoring in Anesthesia
พญ.เพชรรัตน์ วิสุทธิเมธีกร
พ.บ., ป. ชั้นสูงสาขาวิสัญญีวิทยา, วว.(วิสัญญี)
ภาควิชาวิสัญญีวิทยา
วิทยาลัยแพทยศาสตร์กรุงเทพมหานคร
และวชิรพยาบาล

2. Topic module 1.รู้วัตถุประสงค์และความสำคัญในการเฝ้าระวัง
2.รู้จักข้อบ่งชี้และขัอห้ามในการใช้เครื่องเฝ้าระวัง
3.สามารถใช้และแปรผลค่าที่ได้จากเครื่องเฝ้าระวัง
( NIBP , SpO2 , ECG , ET-CO2 )

3. Contents Introduction What is monitoring?
Which, Why and How to monitor?
Level of monitoring
Standards for basic intraoperative monitoring ( ASA)
Systematic monitoring
Conclusion

4. 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)

5. What is monitoring? to monere (การเฝ้าระวัง, การเตือนภัย)
Physiologic parameter & Patient safety parameter
Clinical skills & Monitoring equipment
Data collection, interpretation, evaluation, decision
Problem seeking, Severity assessment, Therapeutic assessment, Evaluation of Anesthetic interventions

6. Patient Monitoring and Management
Involves …
Things you measure (physiological measurement, such as BP or HR)
Things you observe (e.g. observation of pupils)
Planning to avoid trouble (e.g. planning induction of anesthesia or planning extubation)
Inferring diagnoses (e.g. unilateral air entry may mean endobronchial intubation)
Planning to get out of trouble (e.g. differential diagnosis and response algorithm formulation)

7. Level of monitoring Standards for basic intraoperative 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)

8. 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

9. Monitoring in the Past
Visual monitoring of respiration and overall clinical appearance
Finger on pulse
Blood pressure (sometimes)

10. Monitoring in the Past
Finger on the pulse

11. 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 )

12. Examples of Multiparameter Patient Monitors

13. Some Specialized Patient Monitors
Transesophageal
Echocardiography
Depth of Anesthesia Monitor
Evoked Potential Monitor
Some Specialized Patient Monitors

14. 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

15. Cardiovascular monitoring
Electrocardiography
Cardiac activity
Arrhythmia: Lead II
Myocardial ischemia: ECG criteria
Electrolyte imbalance
Pacemaker function

16. Cardiovascular monitoring
การบ้าน ECG
1. การติด lead II, modified V5
2. การแปรผล สาเหตุ การรักษา
-arrhythmia : bradycardia, tachycardia, AF, PVC, VT, VF
-Myocardial ischemia
-electrolyte imbalance

17. Cardiovascular monitoring
Non-invasive blood pressure (NIBP)
Cuff: width % limb diameter, air bladder includes more than halfway around limb
Manometer: aneroid, mercury
Detector: manual, automated
การบ้าน
หลักการทำงาน
หลักการเลือกขนาด
ค่าที่ได้ ค่าใดถูกต้องและเชื่อถือได้มากที่สุด
สถานะการณ์ใดรบกวนการวัดและรบกวนอย่างไร

18. Cardiovascular monitoring
Non-invasive blood pressure
Inaccurate: cuff size, inflated pressure, shivering, cardiac arrhythmia, severe vasoconstriction
Proper application
Narrow cuff
Loose cuff

19. 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

20. 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 ??? ( การบ้านข้อที่เท่าไรแล้วคะ)

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

22. Cardiovascular monitoring
Cardiac filling pressure monitor
Frank-Starling curve: optimum Preload maximize ventricular performance (Stroke volume, CO.)
Preload = Myocardial fiber length (2.2 micron)
LV Preload  LVEDV  LVEDP  LAP  PCWP  PAP  RVP  RAP  CVP
Myocardium function, LV compliance, Mitral valve, Airway pressure, Pulmonary vascular resistance, Pulmonic valve, Tricuspid valve

23. Cardiovascular monitoring
Cardiac filling pressure monitor
LV Preload  LVEDV  LVEDP  LAP  PCWP  PAP
LVEDP  RVEDP  RAP  CVP

24. Cardiovascular monitoring
Cardiac filling pressure monitor
PCWP: Pulmonary capillary wedge pressure
CVP: Central venous pressure

25. Cardiovascular monitoring
PCWP: Pulmonary capillary wedge pressure
CVP: Central venous pressure
Fluid Challenge test to optimize preload and maximize Cardiac performance

26. Respiratory monitoring
Ventilatory monitoring
Oxygenation monitoring
Machine and Circuit monitoring
Clinical skills
Monitoring devices

27. 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

28. 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

29. Ventilatory monitoring
Capnogram : normal curve
1. Dead space air (no CO2)
2. Mixed bronchus & alveolus air (CO2 upstroke)
3. Alveolus air (CO2 plateau)
Inspiration 3
ETCO2 2 1

30. 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

31. การบ้าน (เขียน waveform of ET-CO2 และสาเหตุ)
Capnograph
-esophageal intubation
-bronchial intubation
-airway obstruction
-circuit disconnect
-circuit leakage
-partial rebreathing
-spontaneous breathing (recovary of neuromuscular blockade)
-hypoventilation

32. 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

33. Oxygenation monitoring
Pulse oximeter
Percent of oxyhemoglobin / total hemoglobin
Oxyhemoglobin absorp 940 nm.
Deoxyhemoglobin absorp 660 nm.
Caution: SpO2  PaO2

34. Oxygenation monitoring
Pulse oximeter
SpO2 correlates with PaO2 as in Oxygen-hemoglobin dissociation curve
SpO2 90  PaO2 60 mmHg
(moderate hypoxemia)
75  mmHg
(mixed venous oxygen sat.)
50  mmHg
(P50)

35. 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

36. การบ้าน
Wave form Pulse oximeter
Pulse oximeter artifacts กระทบต่อการแปรผลอย่างไร
Cause of Rt-Lt shift of oxygen-hemoglobin dissociation curve

37. 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

38. Depth of Anesthesia Clinical Signs EEG monitoring
eye signs
respiratory signs
cardiovascular signs
CNS signs
EEG monitoring
Facial EMG monitoring (experimental)
Esophageal contractility (obsolete)

39. Neurologic monitoring
Depth of anesthesia ( BIS )
EEG
Evoked potentials
Cerebral blood flow
Intracranial pressure

40. Neuromuscular monitoring
Clinical skills
Monitoring device :
PERIPHERAL NERVE STIMULATOR

41. Volume status and renal monitoring
Estimate blood loss
Urine output
Hemodynamic stability

42. Volume status and renal monitoring
Estimate blood loss
Urine output
Hemodynamic stability

43. Electrolyte / Metabolic monitoring
Fluid balance
Sugar
Electrolytes
Acid-base balance

44. Coagulation Monitoring
PT / PTT / INR
ACT
Platelet counts
Factor assays
TEG
Clinical sign

45. Temperature monitoring
4 mechanism of heat loss
Perioperative hypothermia (BT<36)
Core temperature : nasopharynx, esophageal, tympanic membrane, pulmonary a. catheter, bladder, rectum

46. Temperature Monitoring
Rationale for use
detect/prevent hypothermia
monitor deliberate hypothermia
adjunct to diagnosing MH
monitoring CPB cooling/rewarming

47. 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

48. Conclusion การบ้านกี่ข้อแล้วคะ มีเครื่องมือเยอะจัง ไม่ได้อย่า out ต้องรู้ NIBP,ECG,ET-CO2,SpO2