Sleep and NIV (Raf) Flashcards
Bipap and not tolerating it, what are the causes?
Blowing into the eyes Poor mask and headgear fit High leak Inappropriate settings Not de-sensitized with mask Poor sensing - dyssynchony Lack of humidification
Differential for central hypoventilation?
Drugs - narcotic, anticonvulsant
Infection
Metabolic - hypoglcemia, fatty acid disorder, metabolic alkalosis
Structural - CNS hemorrhage, Arnold chiari malformation type 2, myelomeningocele
Intrinsic: congenital (CCHS), late onset (ROHAD)
Sleep related breathing abnormalities in prader willi syndrome?
- Increased amount of REM sleep
- Disturabances in circadian rhythm and excessive daytime sleepiness
- Obesity and hypotonia—>OSA
- Absence of ventilatory response to peripheral chemoreceptor stimulation—>abnormal arousals during sleep
- Obesity reduces central chemoreceptor sensitivity, which is improved with growth hormone
- But there has been sudden death in PWS kids started on growth hormone
- Need to do overnight PSG before initiation of GH in child with PWS, repeat PSG in a few weeks and yearly
What is late onset central hypoventilation?
- A trigger such as: pneumonia, severe obesity or cor pulmonale cause hypoventilation
- ROHAD - rapid onset obesity with hypothalamic dysfunction, hypoventilation and autonomic dysregulation
Gene for CCHS?
PHOX2B (autosomal dominant)
Diagnostic criteria for CCHS?
- There has to be evidence of hypoventilation with no other obvious cause for hypoventilation: no neuromuscular disease, cardiac disease, pulmonary disease
- Hypoventilation (paCO2>60) - in particular during quiet sleep
- onset in first year of life
- Hypercapneic ventilatory challenge—it sounds like this is part fo the diagnostic criteria (not sure if this is separate from PSG)
- Investigations while waiting for genetic results:
- Metabolics - inborn error
- MRI brain
- Echo
- CXR +/- CT
Monitoring for complications of CCHS:
- Cardiac: heart block, prolonged sinus pauases, pulmonary hypertension–>annual 72 hour Holter and echo
- Hirschpsrung disease–>clinical monitoring. If concerning symptoms, then contrast enema and rectal suction biopsy
- Cognitive deficits–>Annual neurocognitive assessment
- Tumors of neural crest origin:
- NPARM: abdo imaging and urine catecholamines q3 months for first 2 years, then q6 months till age 7 years, (then every year)
- PARM with 20/28-20/33: annual chest and abdominal imaging
- PSG: every 6 months till age 3 years, then every year
- All patients: annual echo, Holter, neurocognitive assessment
Supplies for emergency tracheostomy kit?
- Obturator of current tube
- Two extra tracheostomy tubes - current size and size below
- Fully charged suction machine, suction catheters
- Normal saline syringes for installation
- Prepared trach ties
- emergency alogirthm
- phone number
- bagger with mask and connector if child is ventilated
Contraindications/relative contraindications for NIV
- Recent facial or upper airway surgery or burn
- Poor glottic function and inability to protect the upper airway
- Patient preference
- CCHS, requiring ventilation during infancy - since they would require ventilation for significant portion of day and developmental concerns
- copious respiratory secretions
Neuromuscular patient with viral illness who comes into hospital. Baseline saturation of 93%.
Need to implement cough augmentation techniques like cough assist if saturation <95% on room air (either with or without NIV). Cough assist has been shown to decrease chance of intubation.
Lung volume recruitment maneuvers for patient with NMD?
- Stacked breaths (no exhalation in between inspiration) via:
- Lung volume recruitment bag
- volume cycled NIV
- Glossopharyngal breathing
Methods for cough augmentation in NMD?
Inspiration:
* Stacked breaths (no exhalation in between inspiration) via:
* Lung volume recruitment bag
* volume cycled NIV
* Glossopharyngal breathing
Expiration:
* Manual chest wall or upper abdominal thrust
* Mechanical exsufflation with negative pressure
Which method of cough augmentation is most effective?
Mechanical insufflation/exsufflation
Respiratory considerations in a patient with neuromuscular disease?
- Ineffective cough clearance–>airway clearance (eg. cough assist)
- Swallowing dysfunction–>tube feeding, sialorrhea
- Sleep disordered breathing during REM sleep–>non-REM SDB and hypoventilation so use of NIV
Later progression to diurnal hypercapea->daytime ventilation (?invasive ventilation)
(See alogirthm for more details)
Describe components of cough reflex arc
Receptor:
- mechanical receptors from pharynx to terminal bronchiole, diaphragm, pleura. Chemical receptors - eg. capsaicin
Affarnet: vagus, glossopharyngeal
Cough centre: medulla pons
Effarent: vagus, phrenic, spinal motor nerve to diaphragm, abdominal wall muscles
