Hypoventilation syndromes and CCHS Flashcards
What is minute ventilation and why is it regulated?
- Rate and depth of breathing
- Regulated to maintain arterial blood gases and stabilise the pH
What is the function of chemoreceptors?
- stabilise PaO2, PaCO2 and pH (7.35-45)
What do chronic states lead to (pH)
?
Lead to compensation to regulate the pH
What is chronic hypoventilation characterised by(5)?
- Reduced tidal volume and rate
- Hypercapnia (elevated PaCO2 in arterial blood) - Type II resp. failure
- Normal pH as compensation mechanisms initiated
- Kidneys start to compensate
- Bicarbonate levels will be increased
What are the characteristics of cogenital central alveolar hypoventialation syndrome?
- Failure of central respiratory drive associated with sleep
- Chronic hypoventilation
What are the characteristics of obesity hypoventilation syndrome?
- BMI> 30 kg/m2
- Hypercapnia
What are the characteristics of idiopathic chronic aleveolar hypoventilation?
- Inadequate respiratory drive from the brainstem
- Impaired breathing impusles from the spinal cord and peripheral nerve
- Irregulaties in the functionality and morphology of the thorax
What are the characteristics of sleep-related hypoventilation from medical condition or pharmacological influence?
- Due to medical disorder (pulmonary vessels, lung parenchyma, neurological disorders)
- Narcoticsm sedatives, anaesthetics. depressants, muscle relaxants, opioid intake
What are the late-onset symptoms of central hypoventilation (2)
?
- Respiratory failure as a consequence of a respiratory illness
- Hypothalamic dysfunction
What is Congental Central Hypoventilation Syndrome (CCHS)?
- <1500 known cases worldwide (Rare)
- Mutations in transcript faqctor paired-like homebox (PHOX2B) gene located on chromosome 4 (4P12)
- Autosomal dominant
- Increased polyalanine repeat mutations (PARM) in exon3 of the gene (20 alanaines)
- More mutations are associated with more severe dysfunction
- Autonomic nervous system dysregulation
- Severity spans from needing support only at night to multiple life threatening states
- Voluntary breathing intact when awake
- Automatic breathing is absent during sleep
- Stay alive if you remember to breathe
- Mechanical ventilation or diaphragm pacing during sleep
- Shallow breaths taken
What are some CCHS-related symptoms?
- Disrupted ANS - multiple issues around the body:
- Gastrointestinal system (HIRSPRUNG’S disease), constipation, GI motility
- Respiratory - Hypoventilation, shallow breathing, lowered tidal volume, obstructive sleep apnea, gasping, laboured breathing during sleep , changed sensitivity to blood gases , hypoxia, cyanosis
- Cardiovascular system
- Reduced HR variability, inability to regulate your cardiovascular system , arryythmia, reduced or lowered HR (BRADYCARDIA) , Impaired ECG
- Neurological responses : seizures, delay in normal developments, diffused atrophy (astrocytes, glia etc in CNS may be impaired - might lead to psychological impairment, learning disabilities)
- Opthalamologic = occular dysfunction = issues dilating and constricting pupils ( NOT ALL SYMPTOMS ARE PRESENT IN ALL INDIVIDUALS)
- Malignancies - nueral crest malignacies, individuals could have short life expectancies
- Many present in SNS - Ganglioneuromas, ganglioneuroblastomas
- Psychological impairments
- Temperature = great difficulty maintaining normal core temp. Basal temp and metabolluc control impaired .
- Severity is based on alanine mutations
What is the management of CCHS?
- Chronic ventilatory support needed from beginning of lidfe (not responsive to pharmacological therapy)
- Possible diaphragm pacing - electrical impulses transmit to phrenic nerve electrodes
- Older children into adults = mechanical ventilation and non invasive intermittent positive pressure ventilation via face masks
- Concurrent symptoms need managed
- Bronchoscopy is performed every 12-24 monthd
- Allow for diagnosis of granulomas
What are the cardiovascular CCHS symptoms?
- Cardiovascular system
- Reduced HR variability, inability to regulate your cardiovascular system , arryythmia, reduced or lowered HR (BRADYCARDIA) , Impaired ECG
What are ANS related CCHS symptoms?
- Disrupted ANS - multiple issues around the body:
- Gastrointestinal system (HIRSPRUNG’S disease), constipation, GI motility
What are neurological CCHS symptoms?
Neurological responses : seizures, delay in normal developments, diffused atrophy (astrocytes, glia etc in CNS may be impaired - might lead to psychological impairment, learning disabilities)
