I-Pain System Fuzzy pain intensity (FPI) index applied in modelling of acute pain via a...

i-Pain System

Fuzzy pain intensity (FPI) index applied in modelling of acute pain via a pati

ent-controlled analgesia device

Multifaceted Model of Pain Components

NociceptionNociception

PainPain

SufferingSuffering

Pain BehaviorPain Behavior

AcuteAcute

ChronicChronic

Four Dimensions of PainFour Dimensions of Pain Four Dimensions of PainFour Dimensions of Pain

Sensory-discriminative Sensory-discriminative Motivational-affectiveMotivational-affective Cognitive-evaluativeCognitive-evaluative Social-behavioralSocial-behavioral

Problem: Detecting pain Subjective & no direct measurement Clinical: Visual Analogue Scales (VAS) Numerical Rating Scales (NRS) Verbal Rating Scales (VRS) Questionnaire

Pain Intensity ScalesPain Intensity Scales

DescriptiveDescriptive pain scalespain scales

NoNopainpain

MildMild ModerateModerate SevereSevere WorstWorstpossiblepossiblepainpain

Numeric pain scalesNumeric pain scales

NoNopainpain

11 22 33 44 55 66 77 88 99

1010

WorstWorstpossiblepossiblepainpain

00

Visual analog scale (VAS)Visual analog scale (VAS)

NoNopainpain

Pain as worst Pain as worst as it could beas it could be

00 1010

疼痛量尺 ( 正面 )

無法忍受完全不痛

正面

疼痛強度

完全不痛

輕微痛

非常痛

無法忍受

疼痛種類

酸脹 痠軟

緊繃 抽筋

冰冷 灼熱

放電 切割

麻癢 撕裂

VAS

VRS

疼痛量尺 ( 反面 )疼痛量尺 ( 反面 )

完全不痛無法忍受

反面

Evaluation: face scales

McGill Pain Questionnaire 4 groups of

descriptors: Sensory: 1-10 Affective: 11-15 Evaluative: 16 Miscellaneous: 17-20

Pain rating index (PRI) Present pain intensity (PPI):

0-5

The Disadvantage of these methods: Static Pain (not Dynamic Pain) Maybe, the VAS values are similar but the efforts are totally different Time Consuming The On-line Analyzing Pain is impossible

Pain has become the “Fifth vital Sign”

Patient’s chart : BP, HR, RR, and T

The functions of the PCA• Administer small bolus doses of Pain-control drugs• At fixed intervals• Controlled by the patient with the push of a button

bolusinfusion pain scores

(between 0~10)

Button-pressing profile

PCA PatientVASNRSVRS

controlled by patient

(a)

FPI index(between0~10)

Fuzzy ModelAlgorithm

PainPattern

PCA PatientButton-pressing

profile

pain

BPSPZP

(b)Figure1. Block diagram of modelling pain system to interpret the pain measurement (a) Conventional PCA system; (b) PCA+FPI system

i-Pain System:i-Pain System: Information,Information, Intelligent, Intelligent, Sound similar to feeling painSound similar to feeling pain

A Hierarchical Level of i-Pain System

Internet

Drug Demand by Patient

Data in Computer

PCA Pain Database

Data Mining

D/D Ratio Mean Drug C.

Pain Pattern

FPI

PCA PDA

1st Level

2nd Level

3rd Level

4th Level

Clinical DataAcquisition

Clinical DataAnalysis

PCA病患自控止痛系統 資料接收 病患基本資料 檢視及輸出 調劑紀錄 選項 副作用 巡房紀錄 上傳至 Server (via Internet)

The i-Pain System Designed in Post-OP:The i-Pain System Designed in Post-OP:

病患基本資料

檢視及輸出

調劑紀錄

選項

副作用

巡房紀錄

BP (Big Pain or Severe Pain): Two buttons are pushed at least

during 4 lockout intervalsSP (Small Pain or Little Pain): A button is pushed during 4 lockout intervalsZP: (Zero Pain or No Pain): No any button is pushed during 4 lockout intervals

.

The definition of BP, SP, and ZP

(a) Pain Pattern:

75% Overlapped Calculation

For 4 Lockout and Overlap ： BP 、 BP 、 BP 、BP

BP = 100% 、 SP=0% 、 ZP=0%

=Demand

=Delivery

Delivery ： 1mg

=Demand

=Delivery

For 4Lockout and Overlap ： SP 、 ZP 、 SP 、BP

BP = 25% 、 SP=50% 、 ZP=25%

• rules of thumb • imprecise information• personal rules

Anaesthetists Use:

Why Fuzzy Logic in i-Pain System ?

IF Pain_intensity is Big_painTHEN set the Morphine infusion rate to a HIGH LEVEL

Big Pain Small PainZero Pain

Fuzzy System

FPI index

Fuzzy Pain Intensity (FPI) Index

Input Membership Function (9 Levels)

Output Membership Function (11 Levels)

Membership Function:

Fuzzy Rules: 36

)()(

36

1

)()(

36

1

)()(

36

1

iiZPi

ZP

iiSPi

SP

iiBPi

BP

XXR

XXR

XXR

'''

'

'

'

ZPSPBPFPII

ZPZPZP

SPSPSP

BPBPBP

XXXX

RXX

RXX

RXX

(1)

(2)

(3)

(4)

(5)

(6)

(7)

Fuzzy Inference Engine:

Fuzzy Defuzzification:

Center of area (COA):

I

Mn Un

Mn

n

n

( )1

1

Where M is the membership function; U is the universe of discourse; n is the number of rules.

Delivery

Demand(b) PCA D/D Ratio:

TimeTotal

doseDeliveryTotal

_

__

(c) PCA Mean Drug Consumption:

=Delivery

=Demand

Demand/Delivery Ratio ： Delivery=4 ， Demand=7 ； Demand/Delivery Ratio=7/4=1.75

Patients and Results:

(a) Drugs: Morphine , Morphine + Keto for 1 & 2 ml

Patient Male Female

Morphine-1ml dose 258 111 147

Morphine-2ml dose 234 105 129

Morphine + Keto-1ml dose 129 49 80

Morphine + Keto-2ml dose 80 26 54

AgeLockout

Time (min)

Height (cm)

Weight (kg)

Days

Morphine-1ml dose

57.84±

17.327.88±2.1

158.46±

13.99

60.89±

11.475.6±2.63

Morphine-2ml dose

53.41±

15.79

9.29±1.66

161.24± 8.6

68.23±

49.95

5.06±2.35

Morphine + Keto-1ml dose

57.34±

15.59

6.92±1.69

157.88± 8.19

60.09±

10.69

5.43±2.44

Morphine + Keto-2ml dose

41.27±

13.379.4±1.46

153.3± 35.73

65.43±

12.55

4.38±2.52

(b) Drugs: Morphine 1 ml or Morphine 2 ml with

Different lockout time (6 or 10 min)

Patient Male Female

Morphine-1ml dose (6min) 138 57 81

Morphine-1ml dose (10 min) 117 50 67

Morphine-2ml dose (6min) 43 26 17

Morphine-2ml dose (10min) 190 79 111

AgeLockout

Time (min)

Height (cm)

Weight (kg)

Days

Morphine-1ml dose

54.64±

14.496

158.84±

16.94

60.02±

11.82

5.52±2.36

Morphine-1ml dose

62.57±

18.2110

158.27±

8.91

59.44±

10.82

5.80±2.87

Morphine-2ml dose

49.00±

10.336

164.88±

8.91

65.53±

10.27

5.56±2.68

Morphine-2ml dose

54.30±

16.6810

160.6±8.27

65.82±

12.55

4.87±2.14

Surgical Types Dosage Pt. No.

Upper Abdomen

Morphine (1ml)

54

Morphine (2ml)

52

Lower Abdomen

Morphine (1ml)

80

Morphine (2ml)

43

SpineMorphine

(1ml)28

Morphine (2ml)

17

ExtremityMorphine

(1ml)64

Morphine (2ml)

70

(c) Different Surgical Operations

A Hierarchical Level of i-Pain System

Internet

Drug Demand by Patient

Data in Computer

PCA Pain Database

Data Mining

D/D Ratio Mean Drug C.

Pain Pattern

FPI

PCA PDA

1st Level

2nd Level

3rd Level

4th Level

Clinical DataAcquisition

Clinical DataAnalysis

PDA for Interviewing Patients Applied in the assessment of

postoperative pain

The Advantages of Using PDA for

Interviewing Patient

Small ， Light ， Portable High Technology 、 Fancy Search and save data easily Data can be shown in Figures

Pain Location : Displaying an anterior and posterior view of the bodyVAS Score: Displaying an VAS image to the patient

Data Communications:

USBRS232

IrDA

RF

PCA

PDA

Computer

PDA

PC

PCA

PDA as a Messenger for Data Collection

Conventional Interviewing System

(Paper Pain Diary)Current Interviewing System

PDA Interviewing System(Electronic Pain Diary)

Recent works: Fuzzy D/D Ratio Index (2nd Dimen.)

Mining the Web Information for Actionable Knowledge (Drug Amount, Different Drug, Lockout Time, Timing After OP)

The Real Time of FP Index

RS-232

PCA

Receive Tablet PC

Future works:

Acute Pain Center for Multicenter Research Share these technologies, Information & Intelligence for this area of research

Data Mining & Warehousing Chronic Pain (Ex. Cancer Pain)