advances in mechanical ventilation & respiratory therapy

Advances in Mechanical Ventilation &

Respiratory Therapy

Your Host for this Lecture

Chad J. Pezzano MA, RT, RRT-NPSPediatric/Neonatal Clinical

InstructorCardio-Respiratory Services

Albany Medical Center

DisclosureI have interest in

LMA North America - provided supplies for studyOny (Infasurf) - provided educational grant for study

“Randomized Controlled Trial of Surfactant Delivery via Laryngeal Mask Airway (LMA) Versus Endotracheal

Tube”

I will be discussing new innovations in surfactant therapy

Goals & ObjectivesProvide both useful and useless information

during this lecture.

Discuss new innovations in respiratory technology.

Learn about the vast changes occurring with mechanical ventilation.

Discuss why invasive mechanical mechanical ventilation may soon be a thing of the past.

Enjoy this lecture and have fun!

Liquid Ventilation (LV) History

Perfluorocarbons first synthesized during the development of the atomic bomb (Manhattan Project)

Kylstra 1962 – early mice experiments with oxygenated saline

Clark 1966 – PFC’s experiment with mice

1989 Preterm neonatal studies conducted

Leach 1996 multi-center preterm infant study

Liquid Ventilation History Cont.

Bartlett et al 1997 conducted randomized controlled adult trial of PLV.

Kacmarek et al 2006 larger adult study of patients who had ARDS.

What are Perfluorocarbons?

Chemically and biologically inert

Clear and odorless

Undergo no metabolism in kidneys or liver

Oxygen carrying capacity can be three times more than blood.

Toxicity has been shown in some studies.

What are the advantages of LV?

Improves oxygenation

Improved lung compliance

Anti-inflammatory effects

Alveolar and endobronchial lavage

Types of LVTotal liquid ventilation (TLV)

Lungs filled with PFC to a volume which is equivalent to the patients functional residual capacity (approximately 30 ml/kg).

A liquid ventilator is used to generate tidal breathing. A respiratory rate of 4 – 5 bpm is used for optimal CO2

clearance. Tidal volumes range from 15 – 20 ml/kg.

Partial liquid ventilation (PLV) Tracheal instillation of PFC’s in combination with gas

ventilation. Continuous mechanical ventilation and rotating dose will

decrease oxygenation index after 15 ml/kg of perflubron.

Liquid Ventilators

Disadvantages to LV Pneumothorax

Circulatory impairment

Lactic acidosis

Blockage of ETT

Carbon dioxide elimination

Toxicity

X-ray interference

Limited data to use as a standard of care

Cost

Future of LV?Brain cooling

Drug delivery

Gene transfer

Lung protection during CV bypass

Antineoplastic drug delivery

Deep ocean diving

Naval rescue

Space travel

Surfactant Replacement Therapy

SurfactantsCurrent indications (on-label uses):

Treatment and Prevention for RDS in Neonates (Infasurf and Survanta).

Treatment for RDS in Neonates (Curosurf and Surfaxin KL4).

SurfactantTraditionally used in neonates for RDS

Delivery method involves the patient being intubated and surfactant delivered intratracheally.

Investigations have been conducted over the past 15 years on Pediatric and Adult Patients.

Theoretically there is an implication for adult patients.

ARDSDirect Indirect

Pediatric/Adult Surfactant Administration

Calfactant for Direct Acute Respiratory Distress Syndrome (CARDS Study); Wilson et al 2008 – 2012.Multicenter RCT involving hospitals in North America,

South Korea, Australia, Canada, Israel, and New Zealand

Compared Calfactant vs PlaceboPrimary outcome- mortality rateSecondary outcome – ventilator free days

Inclusion Criteria: Respiratory failure due to diffuse infectious pneumonia, aspiration, near drowning, smoke inhalation or industrial gas

Study terminated recently.

Current Surfactant StudiesCurrent studies for alternative delivery methods:

Delivery via LMA Albany Medical CenterUniversity of Minnesota

Potential future studiesNebulized delivery

Future of Surfactant Research

If you would understand anything, observe its beginning and its development

- Aristotle

Non-Invasive Ventilation Nasal CPAP/BiPAP

Issues with Non-Invasive Ventilation

Tissue Necrosis

Skin integrity issues

Mask/Prong positioning

Adherence to therapy

Lot’s of work in acute care settings

New Methods of CPAP/BiPAP Delivery

Helmet CPAP

Helmet CPAP /BiPAP

Other forms of Non-Invasive Ventilation

Drinker Respirator (1929)

Reference: http://historical.hsl.virginia.edu/ironlung/

Emerson Iron Lung & Dräger Iron Lung (1931)

Reference: http://www.neonatology.org/pdf/EmersonInfantRespirator.pdf & http://www.drager-medical.com/media/10/01/39/10013917/vent_cc_100_years_pulmotor_booklet_en.pdf

Chest Cuirass

Hayek RTX

Neurally Adjusted Ventilatory Assist (NAVA)

Mode of ventilation exclusively on the Servo i Ventilator.

NAVA gives the user access to information concerning both the patient’s ability to breathe and the status of the central nervous system.

NAVA delivers assist in proportion to and in synchrony with the patient’s respiratory efforts, as reflected by the Edi signal.

Ideal Technology vs. Current Technology

Central nervous system

Phrenic nerve

Diaphragm excitation

Diaphragm contraction

Chest wall, lung and esophageal response

Airway flow, pressure and volume changes

Ideal Technology

Current Technology

Ventilator

Bedside feedback for the RT

Poor Timing: Asynchrony during SIMV (Infants)

Ineffective triggering predicts increased duration of mechanical ventilation*Marjolein de Wit, MD, MS; Kristin B. Miller, MD; David A. Green, MD; Henry E. Ostman, MD;Chris Gennings, PhD; Scott K. Epstein, MD

Conclusions: Ineffective triggering is a common problem earlyin the course of MV and is associated with increased morbidity,including longer MV duration, shorter VFS, longer length of stay,and lower likelihood of home discharge. (Crit Care Med 2009; 37: 000–000)

Missed Triggers Volume Control

Ineffective Triggers PCV

Even in PSV

Ideal Technology vs. Current Technology

Central nervous system

Phrenic nerve

Diaphragm excitation

Diaphragm contraction

Chest wall, lung and esophageal response

Airway flow, pressure and volume changes

Ideal Technology

Current Technology

Ventilator

Bedside feedback for the RT

Bedside feedback for the RT

Catheter Positioning

Diaphragm Signal

Edi Signals from NAVA Catheter

3 Diaphragmatic Breaths

1 Pneumatic Breaths

Total synchrony

SIMV/PSV NAVA

Parts Needed for NAVA

1. NAVA software

2. Edi Module

3. Edi Cable

4. Edi Catheter

5. Servo I ventilator

What we know so far about NAVA:

Improves patient ventilator interaction

Provides efficient respiratory muscle unloading even at high levels of assist

May provide protective ventilation based on reflexes

Adapts to altered respiratory drive and reflexes

May prevent disuse atrophy

Allows on-line monitoring of respiratory drive

Reference: Critical Care Medicine 2010 Vol. 38, No 10 (Supplement) S555 – S558

ConclusionsSci-Fi is not always too far off.

Older respiratory modalities are coming back as new technology.

It takes a long time for new technology to reach most people.

Thank You