MAGNETIC AND ARTICULATING (MNA) BOUGIE ASSISTED BREATHING TUBE PLACEMENT DURING INTUBATION Dalhousie University Senior Design Project Group #7 GROUP MEMBERS: CHRIS CLONEY LAURA HADLEY BRIAN JOSEPH IAN WESTHAVER SUPERVISOR: DR. TED HUBBARD CLIENTS: DR. ANDREW MILNE 1,2, DR. DENNIS DRAPEAU 1 1 DEPARTMENT OF ANESTHESIA – DALHOUSIE UNIVERSITY 2 SCHOOL OF BIOMEDICAL ENGINEERING – DALHOUSIE UNIVERSITY

Overview 2  Recap  Introducer  External magnet  Testing  Requirements and Recommendations

Problem 3

4

5

6

Last Semester 7 Bougie, a.k.a. Introducer External Magnet

Final Device 8

Introducer – Overview 9 Pictures of how the device is made and describing what is coming next  Tip selection  Design Issues  Tip encasement

Introducer – Type of Tip 10

Introducer – Type of Tip 11

Introducer – Type of Tip 12

Introducer – Type of Tip 13

Introducer – Type of Tip 14  Spherical Magnets  Latex Encasing

Introducer – Design Issues 15 Pictures of how the device is made and describing what is coming next  Flop (Flimsy Tip)  Buckling (Force Direction)  Tip encasement

Introducer – Flop Issue 16 ?  Due to Force of Breathing Tube

Introducer – Flop Issue 17 ?  Due to Force of Breathing Tube

Introducer – Flop Issue 18  Seven 5 mm magnets = 35 mm of magnets  55 mm maximum length  Leaves 10 – 20 mm plastic

Introducer – Buckling Issue 19  Buckling issue occurs when the angle between the trachea and mouth is sharp, and the magnetic tip buckles at the tracheal opening ?

Introducer – Buckling Issue 20 ?

Introducer – Buckling Issue 21

Introducer – Tip Encasement 22 External Magnet brought in

Introducer – Tip Encasement 23 ?

Introducer – Tip Encasement 24 – Control ? – Too Stiff

Introducer – Tip Encasement 25 – Control – Too Stiff  Layered Latex Dipping

Introducer – Final Design 26

External Magnet – Overview 27 Mounting Bracket Pin Handle Magnet Stack Cap

External Magnet – Stack Size 28  The size of the magnet stack was chosen through qualitative testing.  The final magnet stack was as large as possible but still comfortable for a range of hand sizes.

External Magnet - Handle A block of plastic was sized using modeling clay on the intubation mannequin 2”

External Magnet - Handle 1 ” Magnets are sized using standard test procedures discussed last term, and a suitable hole is cut

External Magnet - Handle Steel mounting bracket is designed to hold magnets, and placed in the new cavity at right

External Magnet - Handle Curvature of design intended to give more accurate targeting of trachea, and placement under chin contours

External Magnet - Handle Rounded corners for patient and operator safety

External Magnet - Handle Holes placed for additional mounting apparatus

Testing – Overview 35  Distance  Thick Neck Model  Time Trials  Failure Modes  Neck Positioning

Testing – Distance 36 External Magnet brought down

37 Testing – Distance

Testing – Thick Neck Model 38 Thin pieces of rubber representing an obese patient, or a patient with a goiter or tumour.

Testing – Time Trials 39  Fourteen completed trials:  12 successful on 1 st attempt  2 successful on 2 nd attempt

Testing – Time Trials 40  Fourteen completed trials:  12 successful on 1 st attempt  2 successful on 2 nd attempt

Testing – Time Trials  Fourteen completed trials:  12 successful on 1 st attempt  2 successful on 2 nd attempt  Introducer Only: 8.7 ± 1.4 s (95% CI)  Breathing Tube Placement: 21.5 ± 2.0 s (95% CI) 41 **Confidence interval was calculated assuming t-distribution

Testing – Neck Contortion 42

Destructive Testing – Failure Modes 43 Failure Mode# TrialsForce RequiredDiagram - Notes Tip in tension84.0 ± 1.2 lb (95% CI) One low value of 1.75 lb One ball in tension 33.5 ± 1.5 lb (95% CI) Latex stretched extremely far before rupture Tip in shear314.9 ± 4.0 lb (95% CI) Epoxy crushed but tip did not dislocate **Confidence interval was calculated assuming t-distribution

Requirements 44 RequirementResult Medical grade materials Plastics and metal  Latex Disposable or easily sterilized Introducer: disposable External Magnet: sterilizable Portable, volume less than 3500 cm 3 Introducer: External Magnet: Light, weigh less than 3 kg Introducer: External Magnet: 1-2 attempts to introduce breathing tube Fourteen Trials 12 of 14 successful on first attempt Less than 25 seconds 8.7 ± 1.4s (introducer only) 21.5 ± 2.0s (total)

Recommendations and Unknowns  Material change: Nitrile  Packaging  Cases  Contraindications  Further testing  Cadaver testing  Human clinical trial(s)  Device inspection, classification and approval 45

Anaesthesiologist Using Our Device 46

Anaesthesiologist Using Our Device 47  Clients satisfied with level of completion and quality of work  Quotations from meetings:  “”

Questions ? Thank you to:  Department of Anaesthesia  Dr. Dennis Drapeau  Dr. Andrew Milne  Department of Mechanical Engineering  Dr. Ted Hubbard  Peter Jones  Shell 48