8/20/2019 KUDDLER

1/82

 

KUDDLER

By

EVAN LEWIS

Submitted in partial fulfillment of the requirements

For the degree of Master of Science

Thesis Adviser: Dr. Kenneth Loparo

Department of Electrical Engineering and Computer Science

CASE WESTERN RESERVE UNIVERSITY

August, 2010

8/20/2019 KUDDLER

2/82

CASE WESTERN RESERVE UNIVERSITY

SCHOOL OF GRADUATE STUDIES 

We hereby approve the thesis/dissertation of

 ______________________________________________________

candidate for the ________________________________degree *.

(signed)_______________________________________________

(chair of the committee)

 ________________________________________________

 ________________________________________________

 ________________________________________________

 ________________________________________________

 ________________________________________________

(date) _______________________

*We also certify that written approval has been obtained for any

 proprietary material contained therein.

Evan Lewis

M.S.

Kenneth Loparo

Susan Ludington

Mark Scher 

6/2/10

8/20/2019 KUDDLER

3/82

 

Copyright © 2010 by Evan LewisAll rights reserved  

8/20/2019 KUDDLER

4/82

1

TABLE OF CONTENTS 

Table of Contents………………………………………………………………………..1

List of Figures……………………………………………………………………………2

Abstract………………………………………………………………………………….5

Chapter 1: Purpose and Background…………………………………………………….6

Chapter 2: Design and Method………………………………………………………….8

2.1: Equipment and Software…………………………………………………....9

2.2: Hardware Setup……………………………………………………………12

2.3: Recording Process………………………………………..………………...22

2.4: LabView Program………………………………………………………….23

2.5: MATLAB Program………………………………………………………...50

2.6: User Instructions for Operating the KUDDLER device……………..…....54

Chapter 3: Evaluation…………………………………………………………………..63

Chapter 4: Conclusions and Future Work……………………………………………...70

References……………………………………………………………………………...73

8/20/2019 KUDDLER

5/82

2

Figure 2.1 Block diagram of KUDDLER components and connections………9

List of Figures 

Figure 2.2 Computer and computer connections……………………………...12

Figure 2.3 Schematic of DAQ connections……………………………………..13

Figure 2.4 DAQ with connections………………………………………………14

Figure 2.5 Littmann stethoscope factory design………………………………16

Figure 2.6 Littmann stethoscope final design full…………………………….17

Figure 2.7 Littmann stethoscope final design connections…………………...17

Figure 2.8 Motor controller card………………………………………………18

Figure 2.9 24VDC power supply……………………………………………….19

Figure 2.10 Audio input to audio amplifier……………………………………20

Figure 2.11 Audio output to speakers………………………………………….20

Figure 2.12 KUDDLER bed top………………………………………………..21

Figure 2.13 KUDDLER bed speaker…………………………………………..21

Figure 2.14 KUDDLER bed motor…………………………………………….22

Figure 2.15 Pre-GUI loop initialization………………………………………..24

Figure 2.16 KUDDLER block diagram for initial screen……………………25

Figure 2.17 KUDDLER initial screen…………………………………………26

Figure 2.18 Block diagram for Record screen 1……………………………...27

Figure 2.19 Record screen 1……………………………………………………27

Figure 2.20 Record screen 2 block diagram…………………………………..28

Figure 2.21 Record screen 2……………………………………………………28

Figure 2.22 Record screen 3 block diagram…………………………………..29

8/20/2019 KUDDLER

6/82

3

Figure 2.23 Record screen 3…………………………………………………..30

Figure 2.24 Recording initial setup block diagram………………………….31

Figure 2.25 Recording screen…………………………………………………32

Figure 2.26 Data acquisition loop block diagram……………………………32

Figure 2.27 DAQ Assistant window for Read Signals……………………….33

Figure 2.28 Compression VI window for thoracic band signal……………..34

Figure 2.29 Recording timer loop block diagram…………………………...35

Figure 2.30 Recording final sequence structure block diagram……………37

Figure 2.31 Playback screen 1 block diagram……………………………….38

Figure 2.32 Playback screen 1………………………………………………...38

Figure 2.33 Playback screen 2 block diagram……………………………….39

Figure 2.34 Playback screen 2………………………………………………...40

Figure 2.35 Playback initial setup block diagram…………………………...41

Figure 2.36 Playback screen…………………………………………………..42

Figure 2.37 Motor control loop block diagram……………………………...43

Figure 2.38 DAQ Assistant window for motor signal generation…………..44

Figure 2.39 Playback audio loop block diagram…………………………….45

Figure 2.40 Delete names screen 1 block diagram…………………………..46

Figure 2.41 Delete names screen 1……………………………………………46

Figure 2.42 Delete names screen 2 block diagram…………………………..47

Figure 2.43 Delete names screen 2……………………………………………47

Figure 2.44 Backup data screen block diagram……………………………..48

Figure 2.45 Backup data screen……………………………………………....49

8/20/2019 KUDDLER

7/82

4

Figure 2.46 Recover data screen block diagram……………………………50

Figure 3.1 Heartbeat raw signal……………………………………………..63

Figure 3.2 Heartbeat filtered signal…………………………………………64

Figure 3.3 Heartbeat local peaks……………………………………………64

Figure 3.4 Heartbeat beats determined……………………………………..65

Figure 3.5 Heartbeat full beat lineup cut…………………………………...65

Figure 3.6 Heartbeat full beat lineup cut wrap-around…………………...66

Figure 3.7 Heartbeat amplitude and slope match cut……………………..66

Figure 3.8 Heartbeat amplitude and slope match cut wrap-around……...67

Figure 3.9 Respiration raw signal…………………………………………...67

Figure 3.10 Respiration filtered signal……………………………………...68

Figure 3.11 Respiration approximate derivative…………………………...68

Figure 3.12 Respiration speed and direction signals……………………....69

Figure 3.13 Respiration signals cut for continuous loop…………………..69

8/20/2019 KUDDLER

8/82

5

KUDDLER

Abstract

 by

EVAN LEWIS

This thesis discusses the design, development and, construction of a device to be

deployed in the Neonatal Intensive Care Unit (NICU) to provide health and

developmental benefits to premature infants in an incubator setting. The device, hereafter

referred to as KUDDLER, provides customized access to Kangaroo Care for premature

infants in the NICU when they cannot be with their mothers. One of the important

features of KUDDLER is that it can be customized to the unique respiratory and

heartbeat patterns of the mother. During setup of the unit, the mother’s heartbeat and

respiration signals are recorded and stored in a computer for future use. The KUDDLER

is then placed in an incubator and the infant is placed on top on the device. The

KUDDLER is operated from a computer that is located on a cart and oscillates up and

down with the same respiratory rhythm that would be experienced in direct contact with

the mother and a speaker on the back of the device provides the mother’s heartbeat

sounds. The KUDDLER also retains the heat of the surrounding incubator to provide

 proper warmth for the neonate. 

8/20/2019 KUDDLER

9/82

6

Chapter 1: Purpose and Background

Each year in the United States, 43,750 babies are born premature. These premature

infants are at a higher risk for death, poor growth, poor sleep, and prolonged

hospitalization15 than their full-term counterparts.

Beginning in the 1970s, a program called Kangaroo Care was begun as a response to

these risks and problems. During Kangaroo Care the premature infants are held upright

in skin-to-skin contact against their mother’s chest and underneath a blanket, similar to a

kangaroo’s pouch. This contact has been found to improve the infant’s heath by reducing

mortality 18, 36, stabilizing heart and respiratory rates 1, 9, 14, maintaining 2, 20 or improving

 blood oxygenation 8, 22, increasing body warmth 3, 4, 22, 27, preventing body heat loss 27, 28,

minimizing stress 21, 30, reducing pain 5, 16, 19, 23, improving feeding 25, 26, increasing weight

gain 7, organizing sleep 12, 24, maturing the brain 17, 34, and improving neurobehavioral

development 10-13, 15, 29, 31, 32, 35.

All of these improvements lead to a decrease in the amount of time spent in the hospital

and NICU 33. The average discharge from the hospital for a premature infant regularly in

Kangaroo Care versus an infant without any Kangaroo Care is 10-14 days sooner 6.

Given that the cost of care for a premature infant in the NICU is $1,823.60 per day, for

the 43,750 premature infants a year, that 10-14 day early discharge is a savings of $800

million - $1.1 billion a year.

8/20/2019 KUDDLER

10/82

7

Unfortunately the infants’ mothers aren’t always available to administer Kangaroo Care.

Due to financial responsibility, health problems, or other reasons, the mother may not be

able to give their infant the sufficient amount of care they need. On the other hand, the

infant may not be in stable enough condition to be removed from their incubator for

 prolonged periods of time to be held by their mother.

Thus there is a need for a device that emulates the sensation that the infant receives from

lying on their mother’s chest. This device should fit inside the incubator, for the infant to

lie on, and reproduce the feel, sound, and look of their specific mother’s chest.

There is a United States patent37 that describes a similar device, simulating a mother’s

temperature, heartbeat, and breathing. However, what makes the KUDDLER device

developed in this thesis different is that it is customizable: a mother’s heartbeat and

 breathing patterns are recorded and nearly instantly those signals are used to drive the

device to perform in a manner that is very similar to what the neonate would experience

while on the mother’s chest. It is predicted that the sound and feel of an infant’s own

mother will be more beneficial to the baby, and a clinical study is ongoing to gather the

data necessary to validate this hypothesis.

This thesis describes the design, development, and creation of the hardware and software

of the KUDDLER. The thesis is split up into the hardware and software components of

the device. The hardware is listed in its entirety and then the setup, modification, and

connections of the hardware are described. Next, the LabView program that controls the

8/20/2019 KUDDLER

11/82

8

recording and operation of the KUDDLER is detailed. The MATLAB code that

 processes the recordings is then described. After this, the software is evaluated and

shown to work properly. Finally, the thesis is concluded with future work to be done,

should the live trials be completed successfully.

Chapter 2: Design and Method

This section describes the KUDDLER in its entirety, from hardware to software. First,

the hardware of the KUDDLER and listed in its entirety, and then it is explained exactly

how the hardware is setup. The LabView and MATLAB programs are then described in

great detail. Finally, the actual recording process and operation of the KUDDLER is

explained in the user instructions.

8/20/2019 KUDDLER

12/82

9

2.1: Equipment and Software

Figure 2.1 Block diagram of KUDDLER components and connections

8/20/2019 KUDDLER

13/82

10

ASUS 1005HA-PU1X-BK EeePC Seashell Netbook Computer – Base computer where

all data collection, processing and storage takes place. Chosen for its small size and ease

of use.

 National Instruments LabView 8.6 – Computer program that runs the device during data

acquisition and operation of the device. Also initiates the Matlab program that processes

the acquired data signals. Chosen for the initial run of the device because of its

availability and ease of use.

MATLAB – Computer program used to analyze recorded heartbeat and respiration data,

and manipulate data into a usable driving signal for the device.

 National Instruments USB-6215 Data Acquisition (DAQ) Card – Analog-to-digital data

converter for recording and collection of audio heartbeat signal and respiratory effort

signal.

3M Littmann Electronic Stethescope 4100WS – Used to record heartbeat of the mother.

Chosen for its electrical signal output, frequency bandpass filters, and noise filters

integrated into the stethoscope, despite drawbacks from necessary hacking of the device

and complicated use.

Sleemate RIPmate Inductive Respiratory Effort Thoracic Band – Used to record rise and

fall of mother’s chest.

8/20/2019 KUDDLER

14/82

11

Samson Servo 120a Audio Amplifier – Used to amplify the computer audio signal for the

speaker.

Orientalmotor BLHM015K-100 Brushless DC Motor and Driver Package – Used to

move bed of device up and down to playback the motion of the mother’s chest. Has a

circular cam on the rotor designed with a profile for breathing motion. Chosen to be

relatively quiet, yet strong and reliable.

Potrans FS-04024-1M ITE Power Supply 24VDC @ 1.8A – Powers the electric motor.

Innovox SL-1.1 US Speaker – Bolted to the underside of the bed of the device to

 playback the heartbeat of the mother. Not only gives the sound, but the feel of the

heartbeat as well. Chosen for its slim profile, frequency response, and power.

Tripp-Lite Isobar ISOBAR4ULTRA Diagnostic Surge Suppressor – All devices are

 powered through the surge suppressor to simplify use of the device and to protect the

device and anyone connected to the device from a power surge.

8/20/2019 KUDDLER

15/82

12

The EeePC netbook computer is the heart of the device, where all the data collection,

data processing, data storage, and signals that drive the device originate. The computer

 boots up straight to the LabView program that operates the device, ready for use without

any additional setup. The computer is connected to the National Instruments DAQ

device through a standard USB port. A mouse, connected to another USB port provides

ease of use with the GUI interface of the KUDDLER program. The computer is

connected to the Samson audio amplifier using a standard 1/8-inch RCA cable to the

audio output jack of the computer. The computer and computer connections can be seen

in Figure 2.2.

2.2: Hardware Setup

Figure 2.2 Computer and computer connections

The National Instruments USB-6215 DAQ card is used to record both the heartbeat audio

signal and the respiratory signal from the mother, as well as operate the drive motor that

8/20/2019 KUDDLER

16/82

13

moves the bed of the device. All DAQ connections can be seen in Figure 2.3 and Figure

2.4.

Figure 2.3 Schematic of DAQ connections

8/20/2019 KUDDLER

17/82

14

Figure 2.4 DAQ with connections

The analog input ports on the DAQ card are used to record the differential voltage of the

stethoscope measuring heartbeats and the thoracic band outputs measuring respiration.

The outputs of the Littmann stethoscope are connected to ports 19 and 20 (differential

analog input 2) of the DAQ and the shielded ground wire is connected to port 28 (analog

input ground) of the DAQ. The Sleepmate thoracic band output cables are connected to

 ports 15 and 16 (differential analog input 0) of the DAQ.

8/20/2019 KUDDLER

18/82

15

The speed and direction of the motor are controlled from 2 analog output ports on the

DAQ. The green (5) motor wire controls the speed of the motor and is connected to port

12 (analog output 0) of the DAQ. The input voltage varies linearly from 0V, where the

motor is stopped, to 5V where the motor rotates at 32 rpm. The gray wire controls the

direction of the motor and is connected to port 13 (analog output 1) of the DAQ. Here,

0V provides clockwise rotation and 5V provides counterclockwise rotation. The orange

(3), yellow (4), white (10), and black (11) motor control wires are connected to port 11

(digital ground) of the DAQ card. The orange wire is the reference ground for all the

other motor control wires. The yellow wire is the differential ground, paired with the

green wire, to control motor speed. The white wire is the RUN/BRAKE wire, which is

always set to RUN. The black wire is the START/STOP wire, which is always set to

START. The brown (8) control wire is connected port 10 (digital +5V), which allows the

motor to operate under an external voltage input to control the motor speed rather than

the internal potentiometer. The brown (1), red (2), blue (6), and purple (7) wires were not

connected as they have no effect on the operation of the motor in the current setup. The

 brown wire is the alarm output for the motor. The red wire is the speed output for the

motor. The blue wire is the high voltage input for an external potentiometer. The purple

wire is the alarm reset input for the motor.

The 3M Littmann 4100 is a battery powered stethoscope with functions for noise

reduction, volume control, frequency filtering, and clip recording. Unfortunately, the

 built in recording can only record up to 8 seconds per track on 6 tracks. The stethoscope

8/20/2019 KUDDLER

19/82

16

had no provisions for continuous recording of the heartbeat signal. The stethoscope as

 purchased can be seen in Figure 2.5.

Figure 2.5 Littmann stethoscope

In order to make continuous recording possible, the stethoscope was modified. The

 battery casing was taken apart to remove the speaker and earpiece. The speaker wires

were cut and the speaker and earpiece were discarded. Longer wires were spliced into

the output wires of the stethoscope where the speaker was connected. The other ends of

these wires were connected to the DAQ input ports to record the output of the

stethoscope. Finally, the battery casing was reassembled. The modifications to the

stethoscope can be seen in Figure 2.6 and Figure 2.7.

8/20/2019 KUDDLER

20/82

17

Figure 2.6 Modified Littmann stethoscope

Figure 2.7 Modified Littmann stethoscope connections

8/20/2019 KUDDLER

21/82

18

The Sleepmate RIPmate Respiratory Effort System consists of a belt and a sensor that

measures the inductance changes in the belt and provides a differential voltage that

linearly coincides with the expansion of the patient’s chest. A detachable cable connects

the belt and sensors and the sensor is not energized until it is connected to the belt. The

sensor output wires were modified to facilitate connection to the DAQ input ports.

The motor control lines are connected to the motor controller card with a 12 wire

connector. The card is also connected to a 24VDC power supply with a 2 wire connector,

to power the motor. The controller card is then connected to the motor itself, which is

mounted on the device, through an 8-wire connector cable. The motor controller card is

shown with all connections in Figure 2.8.

Figure 2.8 Motor controller card

The Portrans 24VDC Power Supply provides power to the motor. Using a three pronged

grounded power cable, the red wire was connected to the live (L) input, the white wire

8/20/2019 KUDDLER

22/82

19

was connected to the neutral (N) input, and the green wire was connected to the

functional ground (FG) input. From the controller card the black power wire was

connected to the common (COM) output and the red power wire was connected to the

24VDC (+V) output. The power supply is shown with all connections in Figure 2.9.

Figure 2.9 24VDC power supply

The computer’s audio output port is connected to the Samson audio amplifier with a 1/8th 

inch to RCA connector cable. The output is only a monophonic audio signal. The right

channel of the RCA plug is connected to the right channel port of the amplifier as seen in

Figure 2.10. The amplifier was connected to the Innovox speaker from the amplifier’s

right channel output terminals to the speakers input terminals as seen in Figure 2.11.

8/20/2019 KUDDLER

23/82

20

Figure 2.10 Audio input to audio amplifier

Figure 2.11 Audio output to speakers

The KUDDLER device consists of a base box that contains the motor and speaker, and a

 bedplate that is connected to the base by a hinge and actuated by a motor cam unit at the

other end of the box, lengthwise. The speaker is connected to the underside of the

 bedplate to transfer both the sound and vibration of the mother’s heartbeat. On the bed is

a custom made Z-Flo pad that will retain heat up to 37°C, and two silicone breasts that

8/20/2019 KUDDLER

24/82

21

can be positioned to cradle the baby and allow the baby to see the nipples. The pad and

 breasts will be covered with a cloth slip cover that will be replaced with every infant.

Figure 2.12 KUDDLER bed top

Figure 2.13 KUDDLER bed speaker

8/20/2019 KUDDLER

25/82

22

Figure 2.14 KUDDLER bed motor and cam unit

The power cords for the computer, amplifier, and 24VDC power supply power cord are

all connected to the Tripp-Lite Isobar ULTRA Diagnostic Surge Suppressor. The surge

suppressor is connected to a standard wall socket and has its own power switch to power

the entire device.

To customize the operation of the KUDDLER, heartbeat and respiration from the mother

are obtained through a quick and easy recording process that requires a maximum of 10

minutes and the acquired signals can be used indefinitely. Two 2-minute recordings are

obtained, one of the mother’s heartbeat, and one of the mother’s respiration. These two

measurements are taken separately. When recording, the program samples the

differential voltage from the stethoscope or thoracic band at 8 kHz. The acquired signals

2.3: Recording Process

8/20/2019 KUDDLER

26/82

23

are stored in the files [name]_steth.lvm and [name]_resp.lvm for the heartbeat and

respiration recordings respectively.

To record heartbeat the stethoscope is taped to the mother’s chest, slightly left of center;

this is directly over the heart where the heartbeat signal is strongest. The stethoscope is

then turned on. The attendant then uses the computer to select the appropriate recording

settings and runs the program to record the mother’s heartbeat for 2 minutes. Then the

stethoscope is removed and the thoracic band is placed around the mother’s abdomen

directly beneath the breasts. The wires from the band are connected and the attendant

uses the computer to select the appropriate setting for respiration recording and again

runs the program, which will record the mother’s respiration pattern for 2 minutes.

When the second recording session is finished the program opens, runs, and closes

executable MATLAB code that analyzes the recorded signals and process them to be

stored and used later for playback.

The KUDDLER LabView program is made up of two distinct sections. The first

 provides the look and feel of the GUI interface, and the second is for signal recording

during setup and playback during operation. The entire program is executed within a

continuous loop, so that when the recording or playback is done, the program returns to

the first screen of the GUI to start over again.

2.4: LabView Program

8/20/2019 KUDDLER

27/82

24

At the beginning of this program, going into the GUI loop, is an address to the base

folder for all the data that is used in the program besides the program itself, a path to the

‘names.txt’ file which is a list of names of all the recordings created, and an integer

variable of 0 to begin the case structure inside the loop at case 0. All the GUI objects are

located above the GUI loop for quick reference.

Figure 2.15 Pre-GUI loop initialization

The GUI portion of the program consists of a case structure nested inside a continuous

loop. Each case is the result of a specific button press on the GUI. Within each case is a

sequence structure that has three main blocks: an initialization to set visibility and text for

all buttons and text boxes as well to set all buttons to the off position, a loop to wait for a

 button press, and a determination of which button was pressed and which case/screen to

go to next as a result of the button press. Any data or information that needs to be used in

subsequent cases can be carried through to the next iteration of the loop with a shift

register. For instance, the integer variable used to select subsequent cases is initialized to

8/20/2019 KUDDLER

28/82

25

0 going into the loop and on successive iterations the shift register is used to determine

the case used by the case structure.

Figure 2.16 KUDDLER block diagram for initial screen

The initial screen that appears on startup is case 0 of the GUI case structure. The main

options are between ‘Record’, to record a mother’s heartbeat or respiration, or

‘Playback’, to play back the signals on the KUDDLER device. Other minor options are

‘Backup Data’, to backup recorded signals to a USB flash drive, ‘Recover Data’, to

restore lost recordings from a USB flash drive, ‘Delete Names’, to delete recordings from

the program, ‘Back’, which moves to the previous screen (it has no function on the first

screen), and ‘Shutdown’, to shutdown the program and computer. There is also a static

text box on the computer screen to provide instructions and important information to the

user about the operation of the system.

8/20/2019 KUDDLER

29/82

26

Figure 2.17 KUDDLER initial screen

If the ‘Record’ button is pressed the program moves to case 2 and carries through the

 boolean variable to either record or playback. On this screen the user is prompted to type

the patient’s name into the edit text box and click the ‘Next’ button to proceed. If the

‘Back’ button is pressed, the program returns to the initial screen (case 0). When the

‘Next’ button is pressed the program adds the name entered in the text box to the top of a

list of names from a file, ‘names.txt’. If the name entered is already in the list, it is

moved to the top of the list to simplify the autonomy of the MATLAB analysis program.

The name is also added to the end of a file address to be used to create a new folder for

all of the patient’s recorded data. The program then moves to case 4 and carries through

the list and the address as well as the record/playback boolean.

8/20/2019 KUDDLER

30/82

27

Figure 2.18 Block diagram for Record screen 1

Figure 2.19 Record screen 1

On this screen the user has the option to record either the mother’s ‘Heartbeat’ or

‘Respiration’. If the ‘Back’ button is pressed, the program returns to record screen 1

8/20/2019 KUDDLER

31/82

28

(case 2). In either case the program proceeds to case 5 and carries the boolean option of

either respiration or heartbeat. The record/playback boolean, the name list, and the name

address are also carried through.

Figure 2.20 Record screen 2 block diagram

8/20/2019 KUDDLER

32/82

29

Figure 2.21 Record screen 2

This is the final screen before the program runs the recording part of the program and

serves as a summary and review of all the options chosen on the previous screens. The

operation being performed is listed as record, the patient’s name is displayed and either

respiration or heartbeat is displayed as the recording type. Finally the user is prompted to

click the ‘Run’ button the begin recording. If the ‘Back’ button is pressed the program

returns to record screen 2 (case 4). When the ‘Run’ button is pressed the loop is stopped

and the recording case of the record/playback case structure is run.

Figure 2.22 Record screen 3 block diagram

8/20/2019 KUDDLER

33/82

30

Figure 2.23 Record screen 3

The record case is the true case of the record/playback case structure. The first things

that happen in this case are saving the ‘names.txt’ file with the new name, and changing

the GUI interface to display the waveform input signals from the recording devices. The

user also has the option to stop the recording process before the program automatically

stops the recording after 2 minutes.

8/20/2019 KUDDLER

34/82

31

Figure 2.24 Recording initial setup block diagram

8/20/2019 KUDDLER

35/82

32

Figure 2.25 Recording screen

The main part of the recording case is the data acquisition loop.

Figure 2.26 Data acquisition loop block diagram

8/20/2019 KUDDLER

36/82

33

The DAQ Assistant Express VI reads the analog inputs ai0, ai1, and ai2 continuously

from the NI USB-6215 DAQ card at 8kHz with a memory buffer of 8k samples. ai0 and

ai2 correspond to the thoracic band and stethoscope inputs, respectively. ai1 is an artifact

from a previous temperature feature that was removed and does affect the operation of

the current system.

Figure 2.27 DAQ Assistant window for Read Signals

The data output from the DAQ Assistant is then split into separate signals each for

temperature, stethoscope, and thoracic band. The signal from the stethoscope is written

8/20/2019 KUDDLER

37/82

34

directly to the file ‘[name]_steth.lvm’ in the folder [name] where [name] is the name of

the patient entered in case 2 of the GUI case structure. The thoracic band data is filtered

through a compression VI that takes the mean of the signal for every 800 samples or

10Hz. This eliminates the 60Hz and 120Hz components of the thoracic band output.

This new 10Hz signal is then saved to the file ‘[name]_resp.lvm’.

Figure 2.28 Compression VI window for thoracic band signal

 No temperature signal is recorded in the current version of the device. Whether the

stethoscope signal or thoracic band signal is saved is determined by the

8/20/2019 KUDDLER

38/82

35

heartbeat/respiration boolean chosen in case 4 of the GUI case structure. An indicator in

the other loop of the recording case stops the DAQ Assistant and loop. When the loop

stops a string is sent to a sequence structure to finish the recording case.

The other loop of the recording case includes a timer for the user to watch on the GUI, all

triggers and buttons to stop the recording process, and a signal generation DAQ Assistant

that is not used in the current version of the device.

Figure 2.29 Recording timer loop block diagram

8/20/2019 KUDDLER

39/82

36

The timer is reset when the loop first starts and is set to trigger a true signal on the ‘Time

has Elapsed’ boolean when the timer reaches 120 seconds or 2 minutes. The ‘Elapsed

Time’ output is fed into a circuit to convert the floating number to a string in the form of

‘[hours]:[minutes]:[seconds]’ that is put in a static text box to display for the user.

When either the timer reaches 120 seconds or the ‘Stop’ button is pressed, the ‘stop

check’ indicator is made true, stopping the data acquisition loop. It also stops the signal

generation DAQ Assistant and stops the loop.

The final sequence structure of the recording case first runs the MATLAB program that

analyzes the respiration and heartbeat signals, and then initializes the GUI objects that

were used in the recording case. The program then loops to the beginning of the program

and returns to case 0 of the GUI interface loop.

8/20/2019 KUDDLER

40/82

37

Figure 2.30 Recording final sequence structure block diagram

From the initial screen (case 0), if the ‘Playback’ button is pressed the program moves to

case 1 and carries through the boolean variable to either record or playback. On this

screen the user is prompted to select the name of the recording they want to play back

through the KUDDLER device from a drop down menu and then press the ‘Next’ button

to continue; the program returns to the initial screen (case 0) if the ‘Back’ button is

 pressed. The list of patient names in the drop down menu is loaded from the text file

with the list of names, called ‘names.txt’, as an array. When a patient’s name is selected

that name is selected from the array. When the ‘Next’ button is pressed the program

8/20/2019 KUDDLER

41/82

38

moves to case 3 and carries through the selected name and the record/playback boolean.

Figure 2.31 Playback screen 1 block diagram

Figure 2.32 Playback screen 1

8/20/2019 KUDDLER

42/82

39

This is the final screen before playback begins and serves as a summary and review of all

the options chosen on the previous screens. The operation is displayed as playback and

the patient’s name is displayed. Finally, the user is prompted to click the ‘Run’ button to

 begin operation of the KUDDLER device using the patient’s recorded data; the program

returns to the previous screen (case 1) if the ‘Back’ button is pressed. When the ‘Run’

 button is pressed the program creates two path variables in preparation for finding the

necessary recording files needed to run the device. These files are ‘[name]_bpm.lvm’ and

‘[name]_steth.wav’, located in the ‘[name]’ folder of the current directory, where [name]

is the selected patient’s name. The program then stops the loop and runs the playback

case of the recording/playback case structure.

Figure 2.33 Playback screen 2 block diagram

8/20/2019 KUDDLER

43/82

40

Figure 2.34 Playback screen 2

The playback case begins by opening the LabView data file ‘[name]_bpm.lvm’, which is

the breaths per minute of the recording and is used to drive the motor, and sets up the

GUI interface. The user has a timer on the screen and a ‘Stop’ button to stop the

operation of the KUDDLER device.

8/20/2019 KUDDLER

44/82

41

Figure 2.35 Playback initial setup block diagram

8/20/2019 KUDDLER

45/82

42

Figure 2.36 Playback screen

The rest of the playback case is once again made up of two loops and a sequence

structure. The first loop consists of a signal generating DAQ Assistant to drive the motor

on the KUDDLER device, as well as the same timer structure as in the recording case

without the 2-minute time limit. The breaths per minute number is taken from the ‘Read

from Measurement File’ VI and is multiplied by .16 to scale the number to the voltage

needed to drive the motor at that specific number of rotations per minute.

8/20/2019 KUDDLER

46/82

43

Figure 2.37 Motor control loop block diagram

In this version of the KUDDLER, the output voltage is constant and the DAQ Assistant

needs to only output 1 sample.

8/20/2019 KUDDLER

47/82

44

Figure 2.38 DAQ Assistant window for motor signal generation

When the ‘Stop’ button is pressed the signal sent to the DAQ Assistant is changed to 0 to

stop the motor as well as the execution of the DAQ Assistant and the loop.

The second loop in the playback case is the heartbeat audio. This loop was copied from

an included example VI, called ‘Sound Player.vi’, that came with the LabView program.

The event structure was replaced with a case structure and the case was chosen by the

status of the ‘Stop’ button. This loop opens the sound file ‘[name]_steth.wav’ and writes

it to the computer’s sound card to play it through the computers audio output port. The

audio file loops until it is stopped. This loop is stopped when the ‘Stop’ button is pressed

8/20/2019 KUDDLER

48/82

45

and allows the final sequence structure to run.

Figure 2.39 Playback audio loop block diagram

The final sequence structure in the playback case simply initializes the GUI objects that

the case used. The program then loops back around to the beginning of the program and

returns to case 0 of the GUI interface loop.

From the initial screen (case 0), if the ‘Delete Names’ button is clicked, the program

moves to case 6. On this screen the user is prompted to select the name of the patient

data that they want to delete. The mechanics of this case are similar to case 1 of the

 playback selection; the program returns to case 0 if the ‘Back’ button is pressed. When

the ‘Next’ button is pressed the program moves to case 7 and carries through the selected

name.

8/20/2019 KUDDLER

49/82

46

Figure 2.40 Delete names screen 1 block diagram

Figure 2.41 Delete names screen 1

Case 7 is a summary and review of the user’s selections, similar to cases 3 and 5; the

 program returns to case 6 if the ‘Back’ button is pressed. When the ‘Delete’ button is

clicked the program opens the ‘names.txt’ file, deletes the selected name from the list,

8/20/2019 KUDDLER

50/82

47

and saves the new list to ‘names.txt’. The data folder of the same name is also deleted.

The program then returns to case 0.

Figure 2.42 Delete names screen 2 block diagram

Figure 2.43 Delete names screen 2

8/20/2019 KUDDLER

51/82

48

From the initial screen (case 0), if the ‘Backup Data’ button is pressed the program moves

to case 8. The user is prompted to make sure that a USB flash drive is plugged into the

computer and then press the ‘Confirm’ button; the program returns to case 0 if the ‘Back’

 button is pressed. When the ‘Confirm’ button is pressed the program opens the

‘names.txt’ file on both the computer and the flash drive. For every name on the

computer list the program adds and saves that name to the USB drive list and adds the

data folder of the same name to the USB drive. The program then returns to case 0.

Figure 2.44 Backup data screen block diagram

8/20/2019 KUDDLER

52/82

49

Figure 2.45 Backup data screen

From the initial screen (case 0), if the ‘Recover Data’ button is pressed the program

moves to case 9. The screen is the same as the ‘Backup Data’ screen. When the

‘Confirm’ button is pressed the program opens the ‘names.txt’ file on both the computer

and the flash drive. For every name on the USB drive list the program adds and saves

that name to the computer list and adds the data folder of the same name to the computer.

The program then returns to case 0.

8/20/2019 KUDDLER

53/82

50

Figure 2.46 Recover data screen block diagram

The MATLAB program ‘makewav.exe’ analyzes and processes the heartbeat and

respiration signals that were recorded in the LabView ‘KUDDLER.exe’ program.

2.5: MATLAB Program

First, on lines 6 and 7, the ‘names.txt’ file is read and the first name on the list, which is

the name that just got recorded, is saved in order to open the necessary files. This allows

the program to be completely autonomous, with no need for user input.

The heartbeat signal is processed first. The heartbeat signal is opened in line 12 using

‘dlmread’. Then the signal is offset to be entirely positive in order to avoid any problem

that may occur from absolute value use while finding the magnitude in the frequency

filtering.

8/20/2019 KUDDLER

54/82

51

The signal is then sent through a lowpass filter in lines 19-26 to remove any unwanted

high frequencies from the recording process. The filter is a windowed finite impulse

response lowpass filter with an order of 50 and a cutoff frequency of 500Hz. The signal

transformed to the Fourier domain, filtered in the Fourier domain, and then is

transformed back to the time domain. The absolute value is taken to get the magnitude of

the filtered signal.

On lines 28-30, the signal is then normalized so that the minimum of the signal is -0.9

and the maximum is 0.9. This allows the signal to have the required amplitude without

any chance of clipping when the signal is saved as a .wav file.

In order to get a continuous signal from the 2 minute recording of the heartbeat, the end

of the recording needs to loop back to the beginning without a noticeable change in the

heartbeat signal. The heartbeat as recorded from the stethoscope has a two beat cycle – a

large beat, then a smaller beat. These beats are found throughout the recording. To

locate these beats the absolute value of an approximation to derivative of the signal is

used where peaks in the first derivative are determined by examining an approximation to

the second derivative. This is all done on lines 35-38.

On lines 46-52 all local maxima of the derivate that are above 0.3 throughout the signal

are found and stored in the variable ‘dsmax’. Then from lines 55-63 each of those

maxima is compared to their neighbors. For each maximum, if the next maximum is

within 500 samples it is not used as the next beat. Each maximum that is further than 500

8/20/2019 KUDDLER

55/82

52

samples from its previous neighbor is added to a list of beats ‘dspeaks’. Also, if a

maximum that is within 500 samples from its previous neighbor is greater than the last

maximum added to ‘dspeaks’, it replaces that maximum. Thus all the beats throughout

the recording are found.

 Next, at the beginning of the recording the first small beat is found along with the next

large beat. Lines 70-75 determine which beat is the first small one and sets a variable

‘hbstart’ exactly halfway between that first small beat and the next large beat. At the end

of the file the last large beat is found along with the preceding small beat. Lines 76-81

determine which beat is the last large one and sets a variable ‘hbend’ exactly halfway

 between that last large beat and the preceding small beat. The original file is then cut

from ‘hbstart’ to ‘hbend’. This creates the effect of a continuous heartbeat when the

audio file loops from the end to the beginning.

Finally the signal is cut again at the end to match up with the amplitude and slope of the

signal at the beginning to avoid a loud pop in the signal when it loops around to the

 beginning. This is done in lines 88-101 by finding the last sample that has an amplitude

within .02 of the first sample of the signal and whose slope is within .001 of the first.

 Next, the respiratory recording is processed. The recording is read in using ‘dlmread’ at

line 106. The signal is then filtered through the same filter as the heartbeat signal from

lines 111-118, except the cutoff frequency is now 1Hz.

8/20/2019 KUDDLER

56/82

53

 Now, the respiratory signal is the displacement of the chest at any given time, but the

signal needed to drive the motor must be the speed at which the chest is moving at any

given time. Thus, the approximate derivative of the signal is taken on line 121. Then, in

lines 124-126 the signal is split into a directions component and a magnitude component

to control the direction and speed of the motor, respectively.

 Next, from lines 128-134 the number of breaths taken throughout the recording is

determined by finding every time the direction of chest motion changes. Also, the

magnitude portion of the signal is zeroed whenever the direction component changes to

allow the motor to operate properly. On line 135 the direction component changed from

a -1/+1 signal to a 0/5 signal compatible with the motor. From lines 137-143 the

 beginning of the signal is cut to the beginning of the first full chest rise. From lines 144-

150 the end of the signal is cut to the end of the last chest fall. This creates the effect of a

continuous breathing motion when the signal loops around from the end to the beginning.

From lines 153-159 the average breaths per minute from the recording is calculated.

However, to keep the motion within reason, if the calculated breaths per minute is greater

than 17 or less than 8, the number is brought to within the range of 8-17.

Finally, all the required signals are written to files in lines 162-165. The heartbeat audio

signal is saved as ‘[name]_steth.wav’ using the wavwrite function. The rest are saved

using dlmwrite. The respiration magnitude signal is saved as ‘[name]_control.lvm’, the

respiration direction signal is saved as ‘[name]_dir.lvm’, and the breaths per minute

8/20/2019 KUDDLER

57/82

54

number is saved as ‘[name]_bpm.lvm’.

2.6: User Instructions for Operating the KUDDLER device

Instruction for Operating KUDDLER Device 

Turn on the KUDDLER Device

1. 

On the left-hand side of the cart, plug in the power cord for the Main Power and turn onthe Main Power Switch. The switch will light up when it is on.

2. 

On the right hand-hand side of the cart, turn on the Data Power Switch. The power

switch will light up when it is on.

3. 

On the front of the cart, make sure the right side volume knob of the SAMSON amplifieris turned all the way down (counterclockwise) and press the center power button of theSAMSON amplifier. A blue ring will light up around the power button and a red lightwill light up around the speaker button after a few seconds.

4. 

Pull out the tray with the EeePC Netbook Computer, open the computer, and turn thecomputer on with the power button in the top right of the keyboard.

5. 

The computer will boot up to the Windows login screen. The password is “kuddler”.Type in the password and press Enter.

6. 

Wait 5 minutes until the computer has completely booted up. The KUDDLER interfacewill be on the screen.

Record mother's heartbeat

1. 

Press the ‘Record’ button.

2. 

Type name of patient into text box. Then press the ‘Next’ button.

8/20/2019 KUDDLER

58/82

55

3. 

Press the ‘Heartbeat’ button.

(Continue on next page)4.

 

Stethoscope:

a)  IMPORTANT: Be sure to begin recording within 1 minute of turning on the

stethoscope.  Patient must be completely silent while recording.

 b) 

Under the Computer tray, roll out the bottom tray with the stethoscope and therespiratory band. Take out the stethoscope.

c) 

Tape the stethoscope to the patient’s chest, slightly left of center, where theheartbeat sound will be best picked up.

d) 

Turn on the stethoscope with power button (On/Off).

e) 

Make sure the stethoscope is set to bell mode (BELL MODE SELECTOR). Thisshould be the default setting when the stethoscope is turned on. If it is not, set itusing the FREQUENCY MODE SELECTOR button.

: Correct OR :Incorrect 

f) 

Make sure the stethoscope’s volume is set to 4 bars. This should be the defaultsetting when the stethoscope is turned on. If it is not, use the VolumeIncrease(+)/Decrease(-) buttons to set it.

Bell

8/20/2019 KUDDLER

59/82

56

: Correct : Increase Volume :DecreaseVolume

5. 

Make sure all the recording information is correct and press the ‘Run’ button.

6. 

The recording will stop automatically after 2 minutes. To stop recording sooner, pressthe ‘Stop’ button.

(Continue on next page)7.

 

The program will open a new window to analyze the recording. This window willautomatically close when analysis if finished. After this, the program will return to theRecord/Playback screen.

Record mother's respiration

1. 

Press the ‘Record’ button.

8/20/2019 KUDDLER

60/82

57

2. 

Type name of patient into text box. Then press the ‘Next’ button.

3. 

Press the ‘Respiration’ button.

(Continue on next page)

4.  Respiratory Band

a)  Before putting on the band, adjust band length so that it fits around thechest, directly beneath the breasts. The band should fit snuggly, so thatwhen the patient breathes out fully, the band will not slip.

8/20/2019 KUDDLER

61/82

58

 b)  Place the band around the chest and buckle with the wire inputs facingdown.

c)  Connect the wire leads to the band on both sides of the buckle. The wirewith the “Left Side” tag on it goes on the patient’s left, and the “RightSide” tag on it goes on the patient’s right.

(Continue on next page)

8/20/2019 KUDDLER

62/82

59

d)  IMPORTANT: Wait at least 1 minute while all wires are connected to the

band before beginning recording of respiratory signal. 

5. 

Make sure all the recording information is correct and press the ‘Run’ button.

6. 

The recording will stop automatically after 2 minutes. To stop recording sooner, pressthe ‘Stop’ button.

7. 

The program will open a new window to analyze the recording. This window willautomatically close when analysis if finished. After this, the program will return to theRecord/Playback screen.

8/20/2019 KUDDLER

63/82

60

Run KUDDLER Device

1. 

Press the ‘Playback’ button.

2. 

Select patient name from drop down list. Then press the ‘Next’ button.

3. 

Make sure all the playback information is correct and press the ‘Run’ button. TheKUDDLER device will run indefinitely.

4. 

Turn the right side volume knob on the SAMSON amplifier up to half power (straightup).

5. 

Press the ‘Stop’ button to stop running the KUDDLER.

6. 

Turn the right side volume knob on the SAMSON amplifier all the way down again(counterclockwise).

7. 

The program will return to the Record/Playback screen. To select another mother’srecording to play back, simply return to step 1 of the Run KUDDLER Device section.

8/20/2019 KUDDLER

64/82

61

Backing Up Patient Data 

1. 

To backup patient recordings and data click the “Backup Data” button in the upper leftcorner of the screen.

2. 

Unplug the mouse from the computer and insert the “File Backup” USB stick into theUSB port on the right side of the computer where the mouse was plugged in.

3. 

Click “Confirm” to confirm the backup. All patient data will be backed up onto the“Backup Data” USB stick. The program will then return to the start screen.

4. 

Unplug the “Backup Data” USB stick from the computer and plug the mouse back intothe USB port.

Recovering Backed Up Patient Data 

1. 

To recover patient recordings and data that has been previously backed up, click the“Recover Data” button in the top middle of the screen.

2. 

Unplug the mouse from the computer and insert the “File Backup” USB stick into theUSB port on the right side of the computer where the mouse was plugged in.

3. 

Click “Confirm” to confirm the recovery. All patient data that had been backed up will be recovered. The program will then return to the start screen.

4. 

Unplug the “Backup Data” USB stick from the computer and plug the mouse back intothe USB port.

8/20/2019 KUDDLER

65/82

62

Deleting Patient Data 

1. 

Click on the “Delete Names” button on the bottom middle of the screen.

2. 

Click on the “Patient” drop down menu and select the name of the patient data you wantto delete. Then click “Next”.

3. 

Review the information on the left of the screen and then click “Delete”. The patient datawill be deleted and the program will return to the start screen.

Shutting Down the KUDDLER Device

1. 

Press the “Shutdown” button in the lower right corner of the screen. The program cannot be closed while the program is recording or playing back.

2. 

Turn off Samson Amplifier, Data Power Switch, and Main Power Switch.

8/20/2019 KUDDLER

66/82

63

Chapter 3: Evaluation

The KUDDLER device works as it was intended to. The device records the mother’s

signals through the LabView program and stores them in the desired files. The MATLAB

 program processes the signals as intended, which can be seen in the following graphs,

showing the progress through the program. These signals are shortened samples in order

to be able to see the progress easily. Actual recordings are 120 seconds long, rather than

5 and 30 seconds for the heartbeat and respiration signals, respectively.

The heartbeat signal is first processed.

Figure 3.1 Heartbeat raw signal

8/20/2019 KUDDLER

67/82

64

Figure 3.2 Heartbeat filtered signal

The signal after the windowed FIR filter does not show much difference from before the

filter, as the higher pitched noise is small in amplitude and difficult to view. Also the

signal is normalized to avoid clipping.

Figure 3.3 Heartbeat local peaks

8/20/2019 KUDDLER

68/82

65

Figure 3.4 Heartbeat beats determined

The position of the beats is determined, as well as the maximum amplitudes, in order to

find the large beat and the small beat.

Figure 3.5 Heartbeat full beat lineup cut

8/20/2019 KUDDLER

69/82

66

Figure 3.6 Heartbeat full beat lineup cut wrap-around

As you can see, when the heartbeat wraps around it appears to be one continuous

heartbeat, with the wrap falling directly between two full beats. The only issue is the

small spike that occurs at time 0, which will be cleared up in the next step.

Figure 3.7 Heartbeat amplitude and slope match cut

8/20/2019 KUDDLER

70/82

8/20/2019 KUDDLER

71/82

68

Figure 3.10 Respiration filtered signal

The respiration signal is filtered to reduce noise, giving a smooth rise and fall of the

chest.

Figure 3.11 Respiration approximate derivative

8/20/2019 KUDDLER

72/82

69

Figure 3.12 Respiration speed and direction signals

The derivative of the signal is taken and split into speed and direction of the respiration to

drive the motor.

Figure 3.13 Respiration signals cut for continuous loop

The signals are cut to match the end and beginning of full breaths so that when the signal

loops around from the end to the beginning it appears continuous.

After processing, playback is continuous without any issues and can be run continuously

8/20/2019 KUDDLER

73/82

70

for as long as is necessary without any errors.

The design, programming and implementation of the device was accomplished and the

device has passed biomedical evaluation at the University Hospital Case Medical Center

and is currently undergoing patient testing. The device was designed in an incremental

fashion with new features added as necessary onto the existing base design and code.

Although this is not the most effective from an overall system design perspective, since

this is a prototype device the robustness and functionality took precedent over smooth,

minimal design and the most efficient operation. Once feedback from testing is

complete, the prototype will be transformed to a final design with additional features and

functionality.

Chapter 4: Conclusions and Future

The KUDDLER prototype device was a successful project. Moving forward, the device

will be used in trials with infants in the NICU of University Hospital Case Medical

Center in Cleveland, OH, to determine if the KUDDLER device has a beneficial effect on

the premature infants in the NICU. Assuming the trials successfully conclude that the

KUDDLER is a viable option to supplement the Kangaroo Care program, the device will

need to be redesigned and produced in greater numbers. This redesign would benefit the

device by increasing functionality, streamlining and minimizing the design, and lowering

the cost of the device.

8/20/2019 KUDDLER

74/82

71

In the prototype device there were issues with using the exact recording of the mother’s

respiratory pattern, so an average breaths per minute measurement was calculated and

used to drive to motor at a constant speed. The motor used was not compatible with the

desired implementation of using the exact recording and motion. The motor did not have

the necessary positional feedback to be able to reset the device to a starting position upon

stopping playback. Being a circular rotation, if the cam was not started at a 90° position

to the bed it would not have the full range of motion. Also if it was started at a 0°

 position to the bed, the motion would be very small but twice as fast, as the motor moves

the cam back and forth across its top ridge. A motor with positional feedback would be

 preferable to implement a 1-to-1 playback of the mother’s respiratory pattern.

Another issue that arose was that the Littmann electronic stethoscope was used in a way

that it was not designed for. The stethoscope was designed for short interval use by

doctors performing exams on their patients. It is battery operated and so, in order to

conserve power, is designed to shut off after no buttons have been pressed for 3 minutes.

The stethoscope also only has internal functionality to record 8-second clips of a patient’s

heartbeat. For the device redesign it would be beneficial to have a specially made model

of this stethoscope that is powered by the microcontroller card and has a direct line out to

an audio input on the card so recordings can be as long as is desired and free of any

outside interference.

The need for robustness and functionality also resulted in most of the hardware having

8/20/2019 KUDDLER

75/82

72

more options and performance than was necessary for the device to work properly. The

audio amplifier had two 60W channels when all that was needed was a single 45W

channel for the speaker. The National Instruments DAQ had far more functionality than

was necessary. It had more analog input channels than were utilized (the digital channels

were not used at all) and was able to read and write signals at 250kS/s when the

maximum used was 8kS/s. Finally, a full laptop computer running the Windows XP

operating system was used to operate the device. Not only was this more power and

functionality than was necessary, but the possibility of errors in the operating system and

software was greatly increased. All of these devices could likely be implemented on a

single dedicated microcontroller card. This would greatly decrease the cost of the device

and allow for faster and more streamlined design and functionality. There would also be

fewer variables that could negatively affect performance, such as poor compatibility

 between hardware or bugs in the operating system and software.

8/20/2019 KUDDLER

76/82

73

References

1. Bergman NJ, Linley LL, & Fawcus SR. (2004). Randomized controlled trial of skin-

to-skin contact from birth versus conventional incubator for physiological stabilization in

1200- to 2199-gram newborns. Acta Paediatrica 93

 

(6), 779-785.

2. Bohnhorst B, Gill D, Dordelmann M, Peters CS, & Poets CF. (2004). Bradycardia

and desaturation during skin-to-skin care: No relationship to hyperthermia. J Pediatr 145

 

,

499-502.

3. Bystrova K, Widstrom AM, Matthiesen AS, Ransjo-Aarvidson AB, WElles-Nystrom

B, Wassberg C, Vorontsov I, Uvnas-Moberg K. (2003). Skin-to-skin contact may reduce

negative consequences of the “the stress of being born”: A study on temperature in

newborn infants, subjected to different ward routines in St. Petersburg. Acta Pediatrica

92

 

(3), 320-326.

4. Carfoot, S., Williamson, P., Dickson, R. (2005). A randomized controlled trial in the

north of England examining the effects of skin-to-skin care on breastfeeding. Midwifery

21

 

(1), 80-83.

5. Castral TC, Warnock F, Keite AM, Haas VJ, & Scochi CGS. (in press). The effects of

skin-to-skin contac during acute pain in preterm newborns. European J of Pain, 2007,

available now from doi:10.1016/j.ejpain.2007.07.012.

8/20/2019 KUDDLER

77/82

74

6. Charpak, N., Ruiz-Pelaez, J.G., Figueroa de Calume, Z. & Charpak, Y. (1997).

Kangaroo mother versus traditional care for newborn infants

8/20/2019 KUDDLER

78/82

75

Pediatrics, 110

 

(1 Part 1), 16-26.

12. Feldman, R, Weller A, Sirota L, & Eidelman A. (2002). Skin-to-skin contact

(Kangaroo care) promotes self-regulation in premature infants: Sleep wake cyclicity,

arousal modulation, and sustained exploration. Developmental Psych, 38(2)

 

, 194-205

13. Ferber S.G., & Makhoul I.R. (2004). The effect of skin-to-skin contact (kangaroo

care) shortly after birth on the neurobehavioral responses of the term newborn: a

randomized, controlled trial. Pediatrics, 113

 

(4), 858-865.

14. Fohe K, Kropf S, & Avenarius S. (2000). Skin-to-skin contact improves gas

exchange in premature infants. J. Perinatology, 5

 

, 311-315.

15. Hickson A., Rutherford M,Glover V, Stevenson J, Dore C, Cowan F, & Modi, N.

(2006). Neurological outcome of premature infants following a controlled trial of skin-

to-skin contact. Early Human Development, 82

 

(9), 631-632.

16. Johnston, C.C., Stevens, B., Pinelli, J., Gibbins, S., Filion, F., Jack, A., Steele, S.,

Boyer, K., & Veilleux, A. (2003). Kangaroo Care is effective in diminishing pain

response in preterm neonates. Archives of Pediatric & Adolescent Medicine 157

 

(11),

1084-1988.

17. Kaffashi F, Scher MS, Ludington-Hoe SM, & Loparo K. (2008) Complexity

8/20/2019 KUDDLER

79/82

76

analysis of neonatal EEG and skin-to-skin contact (Kangaroo Care) effects. American J

of Physiologic Regulation & Integrated Computerized Physiology, 289

 

. Under review.

18. Kambarami RA, Chidede O, & Kowo DT. (1998).Kangaroo care versus incubator

care in the management of well preterm infants – a pilot study. Annals of Tropical

Paediatrics, 18

 

(2), 81-86.

19. Kostandy R, Ludington-Hoe SM, Cong X, Abouelfettoh A. & Jarrell J. (in press)..

Kangaroo Care reduces infant crying with heel stick. Pain Management Nursing

 

.

20. Lai H-L, Chen C-J, Peng T-C, Chang F-M, Hsieh M-L, Huang H-Y, & Chang SC.

(2006). Randomized controlled trial of music during kangaroo care on maternal state

anxiety and preterm infants’ responses. International J of Nursing Studies, 43(2), 139-

146.

21. Ludington SM. (1990). Energy conservation during skin-to-skin contact between

 preterm infants and their mothers. Heart and Lung, 19

 

(5 Pt1), 445-451.

22. Ludington-Hoe SM, & Dorsey SG. (1998). Meta-analysis of Kangaroo Care Effects.

J. Investigative Medicine.46

 

(1): p. 175A.

23. Ludington-Hoe, S.M., Hosseini, R.B. & Torowicz D.L. (2005). Skin-to-skin contact

(Kangaroo Care) analgesia for preterm infant heel stick. AACN Clinical Issues, 16(3)

8/20/2019 KUDDLER

80/82

77

373-387.

24. Ludington-Hoe SM, Johnson M, Morgan K, Lewis T, Gutman J, Wilson D. & Scher

MS. (2006). Neurophysiologic assessment of neonatal sleep organization: preliminary

results of a randomized controlled trial of skin contact with preterm infants. Pediatrics,

112

 

, e909-e923.

25. Meier PP. (2001). Breastfeeding in the special care nursery: Prematures and infants

with medical problems. Pediatric Clinics of North American, 49

 

(2), 425-443.

26. Meier PP. (2003). Supporting lactation in mothers with very low birth weight

infants. Pediatric Annals, 32

 

(5), 317-325.

27. Moore, E.R, Anderson, G.C. & Bergman, N. (2007). Early skin-to-skin contact for

mothers and their healthy newborn infants. The Cochrane Database of Systematic

Reviews, 2007 , Issue 3.

28. Moore J, & McDermott, J. (2004). “Body Temperature”. In Every Newborn’s

Health: Recommendations for Care for All Newborns. Washington, DC: Save the

Children.

29. Moran M, Radzyminski SG, Higgins KR., Dowling DA., Miller MJ, & Anderson

GC. (1999). Maternal kangaroo (skin-to-skin) care in the NICU beginning 4 hours

8/20/2019 KUDDLER

81/82

78

 postbirth. MCN (American J. of Maternal/Child Nursing), 24

 

(2), 74-79.

30. Morelius, E, Theodorsson E, Nelson N. (2005). Salivary cortisol and mood and pain

 profiles during skin-to-skin care for an unselected group of mothers and infants in

 Neonatal Intensive Care. Pediatrics 116

 

(5), 1105-1113.

31. Ogi S, Arisawa K, Takahashi T, Akiyama T, Goto Y, Fukuda M, & Saito H. (2001).

The developmental effects of an early intervention program for very low birthweight

infants. No To Hattatsu, 33

 

(1), 31-36.

32. Ohgi S, Fukuda M, Moriuchi H, Akiyama T., Nugent JK, Brazelton, TB, Arisawa K,

Takahashi T, & Saito H. (2002). The effects of kangaroo care on neonatal

neurobehavioral organization, infant development and temperament in healthy low-birth-

weight infants through one year. J. Perinatology, 22

 

(5), 374-379.

33. Ramanathan K, Paul VK, Deorari AK, Taneja U, & George G. (2001). Kangaroo

mother care in very low birth weight infants. Indian J Pediatrics, 68

 

(11), 1019-1023.

34. Scher MS, Kaffashi F, Ludington-Hoe S, Johnson MW, Holditch-Davis D, & Loparo

KA. (2008). Neurophysiologic assessment of brain maturation: Preliminary results of an

eight-week trial of skin contact with preterm infants. Pediatric Research.

 

Under review.

35. Tessier R, Cristo MB, Velez S., Giron M, Nadeau L, Figueroa de Calume Z, Ruiz-

8/20/2019 KUDDLER

82/82

Palaez JG, & Charpak, N. (2003). Kangaroo mother care: A method for protecting high

risk, low birth weight and premature infants against developmental delay. Infant

Behavior and Development 26 (3), 384-397.

36. Worku H, & Kassie A. (2005). Kangaroo mother care: a randomized controlled trial

on effectiveness of early kangaroo mother care for the low birth weight infants in Addis

Ababa, Ethiopia. Journal Tropical Pediatrics, 51

 

(2), 93-97.

37. Odiwo, "Infant Nutruring Medical Device," U.S. Patent 6,918,770 B2, Jul. 19, 2005.