Respiratory disease main cause of deathin Spinal Cord Injury

• A & P Refresher

• Acute phase– Respiratory

• Physio Techniques

• Weaning

– Cardiovascular– Tracheostomies– Prognosis

68 patients>C5 88% needed intubatingC5-C8 60% needed intubating

Velmahos gc et al American surgeon 2003

Harop et al Journal of neurosurgery spine 2004

156 Patients

Injuries C2-C8

107 required tracheostomies

Respiratory compromise Level of injuryAgePremorbid resp. disease

MAG (myelin-associated glycoprotein), Omgp (oligodendrocytemyelin glycoprotein), KDI (synthetic: Lysine–Asparagine–Isoleucine ‘g-1 of Laminin Kainat Domain’),Nogo (Neurite outgrowth inhibitor), NgR (Nogo protein Receptor), the Rho signaling pathway(superfamily of ‘Rho-dopsin gene including neurotransmitter receptors‘), EphA4 (Ephrine), GFAP(Glial Fibrillary Acidic Protein), different subtypes of serotonergic and glutamatergic receptors, antigens,antibodies, immune modulators, adhesion molecules, scavengers, neurotrophic factors, enzymes,hormones, collagen scar inhibitors, remyelinating agents and neurogenetic/plasticity inducers

Trauma↓

Haemorrhage/Inflammatory mediators↓

Oedema↓

Ischaemia↓

Oedema↓

Ischaemia

↓Oedema

↓Ischaemia

↓

Pathophysiology

Level of Injury vs Incidence

0

10

20

30

40

50

60

Cervical Thoracic Thoracolumbar Lumbosacral

%

Age vs Incidence

0

5

10

15

20

25

30

0-10 11-20 21-30 31-40 41-50 51-60 >60

%

Cardiorespiratoryphysiology

Respiratory Afferents

Intrapulmonary receptors VagusStretch/proprioreceptors ribs/intercostals T1-T12Clavicles Low Cervical

Chemoreceptors Carotid bodyChemoreceptors Brainstem

Acute changes

Damaged cord becomes unresponsive Flaccid, areflexic

Lasts for 6 days to 6 weeks

Respiratory

• Can’t breath

• Can’t cough

Lumbar Unable to cough 100-70%

Low thoracic chest wall compliance Vital capacity

High thoracic chest wall compliance 30-50% Vital capacitypoor expansion. Basal collapse

C5/C6 Diaphragms, Scalenes, 20%

C3/C4/C5 Sternomastoid and partial diaphragm

Above C3 Sternomastoid only 5-10%

Acute VC 1 Year VC

100-70%

40-50%

60-70%

FVC

0

0.5

1

1.5

2

day

Litr

es

Acute changes respiratory autonomic

Bronchial hypersecretionBronchial hyper-responsiveness

Not forgetting…

Head injuriesChest wall traumaPulmonary contusionHaemopneumothoraxPE / Fat embolus

Acute Respiratory monitoring

Lung function FVC, PEFR, Speech, RR, Resp Pattern

FVC> 1LFVC < 1LFVC= Tidal volume

Pulse oximeter

Blood gases

Watch closely in an appropriate environment for several days

Acute Respiratory Treatment

Oxygen

A good physiotherapist !

Early Respiratory System Complications

Atelectasis

Hypersecretion

Bronchospasm

Pulmonary Oedema

Pneumonia

Chest Trauma

Respiratory Failure

Pulmonary Thromboembolism

Respiratory assessment

• FVC

• Observations - mode of ventilation, FiO2, SaO2, RR

• ABGs, CVS• CXR• Auscultation• Cough?

Observation of breathing pattern

Paradoxical breathingUnilateral breathingAbdominal breathingRespiratory rateCough

Importance of FVC

• Around or less than 1L

Non Invasive Management?

• Regular FVC

• Chest physiotherapy

• Cough assist + manual techniques

• IPPB with the nurses

• Spinal stability?

• Nutrition?

• Don’t wait to intubate if it is inevitable…

Less than 500ml…

Intubation?

• The Neurological level of Injury and completeness of injury are the most important predictors of requirement for tracheostomy

• Early semi-elective intubation during the day by senior experienced staff is preferable to emergency intubation

• Care should be taken when considering extubation of high cervical cord injured patients following stabilisation surgery

Ventilation?

• Some evidence that higher inspiratory pressures reduce the effects of atelectasis

• Rather than a high PEEP

• PEEP aim for 5 cmH2O

• ETv around 500ml or 15-20ml/kg

• NICE Guideline 6-8ml/kg LPV

Secretion Management

Secretion management• Carbocysteine• N acetylcysteine nebs• Saline nebs ?• Bronchodilator nebs• Hyoscine?• Azithromycin / colistin nebs for colonisation

• Supraglottic suction tubes

Positioning: Supine vs Sitting

• FVC must test in supine

• In head tilt down increases by 6%

• Sat upright decreases by 14%

• Use of a binder helps in sitting

• Roll your patients…

• Combine therapy with nursing requirements

Aggressive Management of Atelectasis

• Expansion / loosening of secretions to reduce mucus plugging

• Use of ‘sighs’ within Mechanical Ventilation

• Four hourly bronchodilation, heated humidification & Mucolytics

• The Vest?

• Intrapulmonary Percussive Ventilation?

The Vest

Respiratory techniques• Suctioning

- unopposed vagal stimulation: atropine nearby

• Expiratory vibs / shakes / percussion• The Cough Assist Machine?• Assisted cough• MHI• Inspiratory Muscle Training• VFB/Weaning

Insert expanding lung please! RIK!

Please Do…

• ASIA charting

• Refer to MASCIP guidelines for moving & handling

• Positioning and skin care

• Pressure care mattress

• Bowel routine: More MASCIP guidelines

• Limb care

Please Don’t…

• Sit patients up - yet

• Use a Tilt Table – yet

• Sit your patient on the edge of the bed – ever!

•

WEANING…

Ventilated spinal injured patients

• 15-20% Initially ventilated• 98% Weanable• 1% Nocturnal ventilation• 1% Fully ventilator dependant

• = 8-12 patients/yr• ~ 120 patients in UK

Weaning

Based on little evidence but vast experience

PrerequisitesGood pulmonary complianceLow FiO2 requirementAwake and cooperativeSome respiratory activityCommitted team

Any respiratory activity?

TestingVolume measurement

Beware sensitive ITU Vents

Modified brainstem death test

Progressive ventilator free breathing

Measure Vital Capacity

VC Time off Vent

<250 mls 5 Mins-500 mls 15 Mins-750 mls 30 Mins-1000 mls 60 Mins

Measure VC Post weaning >70% pre weaning

Southport Spinal Injury Centre

Weaning

Increase duration and/ or frequency

Weaning

Wait for spasticity

Bronchodilators

?High TV Ventilation (>20 ml/Kg)?1

Supine

1. The effect of tidal volumes on the time to wean persons with high tetraplegia from ventilators Peterson W. et al spinal cord 1999 37(4):284-288

Weaning

Off vent requires PEEP/CPAP to reduce atalectasisBest option cuff with speaking valve.Ditch the ITU vent

Don’t reduce pressure support too farTry to stick to planAim for off all day, support at night

Speech essentialEating optional

How to wean

BIPAP/ PS

laryngeal function vs resp function

Cuff down on vent

VFB speaking valve

VFB Cuff up

VFB Cuff down speaking valve

Downsized uncuffed tube

Decannulate

Fast weanersSlow weaners

How successful ?

Southport spinal injuries unit

• 246 patients over 20 years

• 63% weaned• 33% Ventilator dependant• 4% Died

Post weaning Maintenance

‘ Maintain Range of Movements’Manual hyperinflationIPPBCough Assist/ Clearway

Improve muscle strengthInspiratory muscle training

Cardiovascular

• Can’t squeeze

• Can’t speed up

SympatheticParasympathetic Parasympathetic

VasodilationVasoconstriction T6 Balance point

Hypotension, bradycardia, tendency to asystole

Acute changes cardiac

Be careful…..

Neurogenic pulmonary oedema

Postural hypotension

Vagal stimulation (tracheal suction)

Pressure sores

Aim to maintain adequate perfusion

Vale et al, Journal of neurosurgery aug 1997Combined medical and surgical treatment after acute spinal cord injury: results of a prospective studyTo assess the merits of aggressive medical resuscitation and blood pressure management

Hypotension

Bradycardia

(Pacemakers)

How high?How long?

Other common problems…

• Nutrition and GI tract

• Renal function

• Temperature control

• Psycological

• DVT– 30% incidence

• Documentation

• Pain

Chronic Changes Respiratory

VC Improves Cough improvesSecretions lessen

Long term ?

Sleep disordered breathing

Chronic Changes Cardiac

Postural hypotension stays

Vagal hypersensitivity fades

Bradycardia remains

Chronic Changes Cardiac

Autonomic dysreflexiaAutonomic hyperreflexia

Sympathetic discharge due to autonomic stimulus

Peripheral and central vasoconstriction below injury levelCompensatory vasodilatation above injury level

Severe hypertension, headache, Bradycardia

T6 and above

Sweating above injury level

Asystole, myocardial infarction, cerebral haemmorhage

Chronic Changes Cardiac

Autonomic dysrefflexia

Triggered by……….

Bladder distensionBowel distensionMinor infectionsMajor infections

Treat by………..Remove causeNifedipineGTN

Tracheostomy

• Surgical may be better than percutaneous– Safer if unstable spine– Anatomically accurate– Easier changes long term– Worse scar– Logistically difficult

Trachy Tubes

Use what you are used to but…

Avoid fenestrations

Trachy Tubes

Definitely avoid

Trachy TubesDefinitely consider supraglottic suction tubes

Trachy TubesIf they need a tube long term

Trachy Tubes

Trachy TubesDon’t dismiss

Speaking valves Are not all the same

When to decanulate

No respiratory support required

Secretion clearance guaranteed

Survival

0

10

20

30

40

50

10 15 20 25 30 35 40 45 50 55 60 65 70 75

Age at Injury

Yrs

C5-C8

C1-C4

Vent dependant

National Spinal Cord Injury Statistical Centre, University of Alabama

Hospitalised 1 year mortality 15%

Prognosis – FunctionC1-3, C4

• Ventilator Assisted• Communication• Verbal Independence• Powered chair• Environmental Controls

• Full time carers

C5

• Drink, wash groom with adaptions

• Hand control power chair, some self propel

• Full time carer