respiratory care in neuromuscular disease n.
Skip this Video
Loading SlideShow in 5 Seconds..
Respiratory Care in Neuromuscular Disease PowerPoint Presentation
Download Presentation
Respiratory Care in Neuromuscular Disease

Loading in 2 Seconds...

play fullscreen
1 / 59

Respiratory Care in Neuromuscular Disease - PowerPoint PPT Presentation

  • Uploaded on

Respiratory Care in Neuromuscular Disease. Cori Daines, MD Pediatric Pulmonary Medicine University of Arizona. Neuromuscular Disease. Duchenne’s muscular dystrophy Becker’s muscular dystrophy Limb-Girdle muscular dystrophy Spinal muscular atrophy Myotonic dystrophy. Neuromuscular Disease.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Respiratory Care in Neuromuscular Disease' - gary-watkins

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
respiratory care in neuromuscular disease

Respiratory Care in Neuromuscular Disease

Cori Daines, MD

Pediatric Pulmonary MedicineUniversity of Arizona

neuromuscular disease
Neuromuscular Disease
  • Duchenne’s muscular dystrophy
  • Becker’s muscular dystrophy
  • Limb-Girdle muscular dystrophy
  • Spinal muscular atrophy
  • Myotonic dystrophy
neuromuscular disease1
Neuromuscular Disease
  • Genetically inherited
  • Muscle weakness
    • Extremities
    • Trunk/spine
    • Respiratory
    • Swallowing
    • Cardiac
neuromuscular disease2
Neuromuscular disease

Controller failure

Chest wall compromise

Muscle weakness



respiratory control
Respiratory Control

Maintain homeostasis


Carbon dioxide

Hydrogen ion concentration (pH)

Optimize mechanical efficiency

Complex functions




Adaptation to disease

respiratory muscles
Respiratory Muscles



Accessory muscles (shoulder girdle)



Abdominal wall


physiologic impact
Physiologic impact

Ventilatory impairment

Oxygenation impairment [(A-a)DO2 ]

Sleep disordered breathing

Maintenance of lung volume

Growth of the lung in children

Lung clearance impairment

Lung inflammation from aspiration

Nocturnal vs diurnal dysfunction varies


Assuming that there is no primary lung disease most NMD patients can have normal lungs

“An ounce of prevention is worth a pound of cure”

4 E’s = “Expansion, Evacuation, Evasion and Evaluation”

i.e. expand the lungs, clear the airways, and avoid aspiration and infection

Evaluate how the patient progresses acutely and over the long term

minimize work of breathing
Minimize work of breathing

Normally 15% of energy = WOB

In NMD this can be exceeded

Decreased use of energy in movement

Increased work of breathing due to inefficient system and/or stiff/obstructed lungs

Increased WOB will lead to chronic hypercapnea and compensatory alkalosis


Weakness leads to

Poor inspiration

Atelectasis and decreased compliance due to fluid accumulation and microatelectasis

Chest wall/Shoulder girdle contracture

Kyphoscoliosis (except DMD)

Loss of MIP correlates with loss of lung volume and MIP < 30 are predictive of increases in CO2

duchenne md fvc vs age
Duchenne MD: FVC vs Age

Bach et al. Arch Phys Med Rehabil 1981; 62:328


Reduced: TLC, VC, FRC, ERV

Balance between chest wall and diaphragm

Affects optimal position (Upright better with weak diaphragm)

Rate of loss of function affects degree of breathing intolerance: Rapid is worse


Optimal humidity and warmth to maintain ciliary function



Close glottis

Pressurize pulmonary gas by tensing abdomen and perineum (200 cm H2O)

Explosively open airway

Continue cough to lower lung volume

Cough peak flow transients are 6 to 12 liters per second; i.e. 360 to 720 L/min

pulmonary clearance failure
Pulmonary clearance failure

Disrupted cilia due to drying and inflammation

Low tidal volume (< 20 ml/kg)

Poor glottic closure

Poor abdominal compression

CPF < 2.7 L/sec = 160L/min predict failure of extubation in adults (i.e. < 2 L/min/kg)

Poor coordination

Inablility to continue to low lung volume


Chest physiotherapy

Stacking with voluntary cough

Stacking with augmented cough

Mechanical insufflation-exsufflationTracheostomy

evasion avoid pulmonary damage
EVASION: Avoid pulmonary damage

Growth failure

Poor expansion

Poor nutrition


Foreign body (tracheostomy)

Poor clearance with inflammatory processes

evasion aspiration
Evasion: Aspiration

A tension exists between natural, pleasure giving aspects of feeding and danger of aspiration and inadequate nutrition

Often this leads to an illogical approach; i.e. pt has to fail oral feeds to go to alternative as opposed to succeed with oral feedings to move off of supportive modalities (NG,GT etc)

Progresses early in SMA/Brainstem dysfunction and later in DMD

Oral hygiene important even if NPO


History and physical including QOL and sleep questionnaire

Chest film

Lung volumes


Sniff MIP

Inspiratory flow reserve

Maximum insufflation capacity

Cough peak flows

patient status changes with viral respiratory infections
Patient status changes with viral respiratory infections

Increased secretions

Decreased muscle strength

Surfactant dysfunction in LRI

Transient increase in need for support

We commonly evaluate patients when they have recovered from an illness or are stable

dr bach outpatient protocol
Dr. Bach: Outpatient Protocol

Patients at risk

During chest colds w/ assisted PCF below 270 LPM

Patients prescribed

Oximeter and MIE device

Patients trained in

Air stacking insufflated volumes via mouth and nasal interfaces

Manually assisted coughing

Mechanical in-exsufflation at [+35 to +50] to [-35 to -50] cm H2O

outpatient protocol
Outpatient Protocol

Patients given 1-hour access to

Portable volume ventilator

Cough Assist MIE (J. H. Emerson Co., Cambridge, MA)

Various mouthpieces and nasal interfaces

Patients and care providers are instructed

SaO2 <95% indicates hypoventilation or airway mucus accumulation that must be cleared to prevent atelectasis and pneumonia

Use SaO2 monitoring whenever fatigued, short of breath, or ill

Use noninvasive IPPV and manually and mechanically assisted coughing as needed to maintain normal SaO2 at all times

outpatient protocol1
Outpatient Protocol

Patients with elevated EtCO2 or daytime SaO2 <95%

Undergo nocturnal SaO2 monitoring

When symptomatic or nocturnal SaO2 mean <94%

A trial of nocturnal nasal IPPV is provided

People continue to use nocturnal nasal IPPV when they felt less fatigue and nocturnal mean SaO2 increases.

Most young patients use noninvasive IPPV for the first time to assist lung ventilation during chest infections.

respiratory muscle aids indications
Respiratory muscle aids: Indications

Failure to maintain a healthy lung with growth and optimal ventilatory function

i.e. failing the 3 E’s

Prevention is key

Optimize support in relation to the needs of the patient

using what the patient has
Using what the patient has

Daytime spontaneous respiration with nocturnal support for control, airway obstruction, recruitment of lung volume

Glossopharyngeal breathing during the daytime with nocturnal ventilation

Optimizing cough and lung volume with stacking maneuvers

maximal insufflation capacity
Maximal insufflation capacity

Breath stacking

Measured unassisted with spontaneous breathes or GPB breaths

Commonly 1.5x the VC

Can be augmented with interface and manual resuscitator bag

Maintain lung volume and compliance and chest wall compliance

inspiratory muscle aids
Inspiratory muscle aids

Rocking bed and abdominal belt

Disadvantage is no expansion of lung; i.e. frc to less than frc

Negative pressure ventilators

Disadvantages are OSAS and aspiration

Non-invasive IPPV

Tracheostomy and IPPV

nocturnal support
Nocturnal support

Used prior to need for 24/7 support

Improves daytime PaO2, PaCO2

Reduces respiratory muscle work at night and rests the muscles

Reverses cor pulmonale perhaps in addition to O2 by improving lung volume

nocturnal support1
Nocturnal support

Increases MIP and lung volume

Improves compliance and FRC during the daytime

Can be used even in patients with severe breathing intolerance

CCHS or Quadraparesis with daytime diaphragmatic pacing

GPB during daytime

Can be transitioned to 24/7 with illnesses

nippv interfaces
NIPPV: Interfaces

Full face mask

Nasal mask

Custom mask

Mouthpiece / Lipseal

Leakage and dental issues

Sipper mouthpiece

nippv nasal mask prongs
NIPPV: Nasal mask / Prongs

2-3 x preferred compared to mouthpiece


Leak, esp mouth

Nasal bridge pressure with mask

Gum erosion or compression with mask

Nasal erosion with prongs

Chin strap may be needed

nippv full face mask
NIPPV: Full face mask

Decreased leak





Nocturnal use with daytime nasal mask

nippv sipper mouthpiece
NIPPV: Sipper / Mouthpiece

Daytime use

Allows facial freedom

Flexed mouthpiece +/- custom orthodontics

Intermittently used to augment breathing

Continuously used

nippv sipper mouthpiece1
NIPPV: Sipper / Mouthpiece

Large VT set on ventilator or High insp flow if pressure controlled

Allows stacking maneuvers

Head/neck control for intermittent use

Use of flexed mouthpiece with a back pressure of 2-3 cmH2O can reduce low pressure/disconnect alarms

complications of nippv
Complications of NIPPV

Facial and orthodontic changes

Aerophagia (PIP > 25 cmH2O)

Nasal drying/congestion = humidify

Volutrauma - air leak



Current view in rehab circles is that with proper care a tracheostomy is never needed

Our experience is that tracheostomy may have a role

Patient preference

Upper airway dysfunction

Severe central airway obstruction by secretions


Pressure cycled vs Volume cycled

Pressure cycled are often triggered by flow sensing reducing work of breathing

Flow sensing is also important in pts with high respiratory rates = infants/toddlers


Leak can vary with sleep, position, and effort which is problematic with volume cycled ventilators

Variable airway resistance and/or pulmonary or chest wall compliance better with volume settings

Pressure cycling limits ability to stack

ventilator triggering and rate
Ventilator triggering and rate

Small/weak or brainstem/CNS pts may not trigger well

Spontaneous-timed modes are useful with a backup rate higher than spontaneous when initiating ventilation in infants/young children

Back-up rates lower than spontaneous once comfortable

ventilation goals
Ventilation goals

Healthy lungs with good volumes and no atelectasis

Rate on the low side and Vt or PIP on the high side

PaCO2 = 35 ± 5 mmHg

Room air

Patient comfort

Ability to trigger vent

Ability to deliver needed volume/flow in time

No auto-PEEP

No auto-cycling / Ventilator-Patient dysynchrony

Primary lung disease may change this approach

bipap settings
BiPAP settings

S/T mode / High span IPAP/EPAP

If OSAS is main issue low span is appropriate

IPAP range 15-18

May need higher with high UA resistance, non-compliant lungs, obesity/non-compliant chest wall

May need to be lower with high spont rates

EPAP range 2-4

Depending upon circuit may need 4 cmH2O to avoid rebreathing

High EPAP is rarely needed

other issues
Other issues

Inspiratory time

I:E of 1:2

Ti of 0.5 min (infant) and 1.0 (>infant)

Insp flow rate necessary to achieve pressure comfortably

Trigger sensitivity set to reduce WOB, but not autocycle

Pressure support may improve comfort with spontaneous breaths

Ultimately creates an S/T mode depending upon settings

control mode ventilation
Control mode ventilation

Limited respiratory control / Inability to trigger breaths

assist control mode
Assist Control Mode

Can trigger breaths, but needs support with each breath

simv mode

Most patients, improved comfort, stable CO2s

bilevel mode
Bilevel Mode

Mimic BiPAP / No Backup Rate

rise time
Rise Time

Pressure control

Pressure support

Flow in volume control is set by Ti and Vt

rise time1
Rise Time

Slow rise time

Small ET

Bronchospasm / AOD

Pressure overshoot on PIP

Fast rise time

Short Ti / High respiratory rate

Vary with age; i.e. larger VT = faster rise time

home ventilation reality
Home ventilation reality

Every patient is unique

These are “more guidelines rather than rules”

Vary settings, interfaces, strategies to achieve goals of good health and optimized quality of life

discharge home medical issues
Discharge home: Medical Issues

Presence of a stable airway

FiO2 less than 40%

PCO2 safely maintained

Nutritional intake optimal

Other medical conditions well controlled

Above may vary if palliative care

Jardine E, Wallis C. Thorax 1998; 53:762

discharge home support
Discharge Home: Support

Goals and plans clarified with family and caregivers

Family and respite caregivers trained in the 4 E’s and all equipment

Nursing support arranged for nighttime

Equipment lists developed and implemented with re-supply and funding addressed

Funding and insurance issues addressed