Patient Monitoring 1

8/8/2019 Patient Monitoring 1

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Patient Monitors

-Janani Venugopalan

-M-Tech Clinical Engineering


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Monitoring

Repeated or continuous observations or measurements of the

patient, his or her physiological function, and the function of life

support equipment, for the purpose of guiding management

decisions, including when to make therapeutic interventions, and

assessment of those interventions .

A patient monitor may not only alert caregivers to potentially life-

threatening events; many provide physiologic input data used to

control directly connected life-support devices.


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Need for PatientMonitoring

Patients with unstable physiological regulatory systems; for example, apatient whose respiratory system is suppressed by a drug overdose oranesthesia

P

atients with a suspected life-threatening condition; for example, apatient who has findings indicating an acute myocardial infarction (heartattack)

Patients at high risk of developing a life-threatening condition; forexample, patients immediately after open-heart surgery or a premature

infant whose heart and lungs are not fully developed

Patients in a critical physiological state; for example, patients with multipletrauma or septic shock.

Mother and baby during the labor and delivery process


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Monitoringinthe Past

Visual monitoring of

respiration and overall

clinical appearance

Finger on pulse

Blood pressure

(sometimes)

Finger on the pulse


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1550 BC - Peripheral Pulse Egyptians

1625 Santorio - Measure body temperature with spirit

1707 Sir John Foyer pulse watch.

1852 Ludwig Taube patients fever measurement

At this time Temperature, pulse rate respiratory rate hadbecome standard vital signs.

1896 Scipione Riva- Rocci introduced the sphygmomanometer.

Nikolai koroktoffapplied the cuff with the stethoscope

1900s Harvey Cushing applied routine blood pressure inoperating rooms.

The aim and philosophy of patient monitoring J. S. S. Stewart

Monitoring in the Past


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1903 Willem Einthoven devised the stringgalvanometer to measure ECG (Nobel Prize 1924)

World war II Development of transducers.

1950 The ICUs were established

Late 60s and early 70 bedside monitors built aroundbouncing balls or conventional oscilloscope.

90Computer-based patient monitors - Systems withdatabase functions, report-generation systems, andsome decision-making capabilities.


Monitoring in the Past


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Low Tech Vs High Tech


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PatientMonitors

Electronic medical device that measures a patient'svital signs and displays the data so obtained, whichmay or may not be transmitted on a monitoringnetwork.

Various Physiological variables being measured Temperature

Heart rate and rhythm

Respiratory rate Blood pressure

Blood-oxygen saturation


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Block Diagram


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Modules

NiBP

SpO2

EtCO2

ECG

Temperature


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Pulse Oximetry

Gives an estimate of oxygen saturation

Uses spectrophotometry based on the Beer-Lambertlaw

Differentiates oxy- from deoxyhemoglobin by thedifferences in absorption at 660nm and 940nm


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Estimates heart rate by measuring cyclic changes inlight transmission

Measures 4 types of hemoglobin: deoxy, oxy,

carboxy, and met

Estimates functional hemoglobin saturation:oxyhemoglobin/deoxy + oxy hemoglobin


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Principle


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Ausculatory

Detection of Korothoff sounds

Oscillometric

Measures the oscillations in the air caused by the

arterial pressure pulse.The machine measures MAP then calculates systolicand diastolic pressure.

Non Invasive Blood Pressure


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Oscillometric Blood Pressure

Intermittent Pressure Measurement

Continuous Pressure Measurement

Vasotrac

T-Line Tensymeter


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Intermittent Pressure

Measurement


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Continuous Pressure

Measurement

Vasotrac

T-Line Tensymeter


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Temperature

Thermistor

Thermocouple

Platinum Wire R = R0(1+T)

Liquid Crystal

Infrared


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RespirationRate

Thermistor Method:

ImpedanceP

neumography

CO2

Method of Respiration Rate Measurement


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ECG


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Types of Monitors

Analog monitors

Digital monitoring

Multi- channel & Multi- Parameter monitors


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Handheld

Portable

Monitor/Defibrillator (usually portable)

Tabletop

Networkable / non-networkable

Wired / wireless data transmission

Mains powered or mains + battery powered

Types of Monitors


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Standards

The major standards and guidelines for this field

include those for anaesthesia

Standards for basic anaesthetic monitoring

Canadian Anaesthetic Standards.

IEC 60601-2-49 - standard concerning particular

requirements for the safety of multifunction patientmonitoring equipment.


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DifferentManufacturers

Phillips

General Electronics

Larsen & Toubro


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Phillips

Phillips monitors come under 2 major classifications .

Intellivue - 9 Models

Suresigns 7 Models

Warranty and service vary according to country andinitial agreements

Includes areas like anaesthesia, Wireless, Portable,Widescreen etc.


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General Elecronics

10 Models & Types

They have multiple ranges in terms of both function

and cost

Includes areas like anaesthesia, MRI Compatible,Wireless, Portable, Widescreen etc.

Warranty and service vary according to country andinitial agreements


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Larsen & Toubro

4 Models

1Portable

Variation in display properties and parameters

measured

5 years spare and labour warranty ( other than

portable model 2 years)


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References Patient-Monitoring Systems - REED M. GARDNER AND M. MICHAEL

SHABOT

Patient Monitors in Critical Care: Lessons for Improvement - Frank A.

Drews, PhD

Understanding Anaesthesia Dorsch & Dorsch

The LightTissue Interaction of Pulse Oximetry Paul D. Mannheimer, PhD


Company websites

Medical Instrumentation John G Webster


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THANK YOU!

Documents

Patient Monitoring 1