2. CASE
• A 73-year-old man, Mr Ahmed, was brought into er department. He had been increasingly confused
over the past few days. By examination: Pulse 108 beats/min, Blood pressure 120/84 mmHg,
Respiratory rate 12 breaths/min and Oxygen saturations 78%.
• On inspection His lips and tongue look blue, hands felt warm and had had a bounding pulse. When
his arms and wrists were extended there was a rhythmic flapping of his hands. His ABG were: pH
7.24 (7.35–7.45) PaO2 42 mmHg (70-100mmHg) PaCO2 66 mmHg (35-45mmHg) Bicarbonate 28
mmol/L (22–28 mmol/L)
• Mr Ahmed was slumped on the trolley but is able to cooperate with simple commands during
examination. Her Glasgow Coma Score was 14. Neurological examination was otherwise
unremarkable. On chest examination he was thin with intercostal indrawing, a tracheal tug and
reduced cricosternal distance. He had no obvious chest wall deformity. He had loss of cardiac
dullness and downward displacement of her liver. He had quiet breath sounds with expiratory
wheeze.
• Mr Ahmed was given 60% oxygen while other investigations were ordered. When they return her
Glasgow Coma Score is 10. Repeat arterial blood gases are: Normal range pH 7.18 (7.35–7.45) PaO2
51 mmHg (70-100 mmHg) PaCO2 76.5 mmHg (35-45 mmHg) Bicarbonate 28 mmol/L (22–28 mmol/L)
3. WHAT TO KNOW
1) What is respiratory failure and its types?
2) What is the etiology?
3) How to diagnose respiratory failure?
4) How to differentiate between severe lung disease and neurological, muscular or
chest wall disease?
5) How to treat a case with respiratory failure?
4. WHAT IS RESPIRATORY FAILURE AND ITS TYPES?
REPIRATORY FAILURE: It is a condition in which the
respiratory system can't maintain an adequate gas
exchange ( Pa02 < 60 mmHg and/or PaC02 > 50 mmHg
)
Type II respiratory failure
Type I respiratory failure
- Hypoxemia with hypercapnia.
- Mainly due to disturbed
ventilation.
- Hypoxemia without hypercapnia.
- Mainly due to disturbed diffusion or
perfusion
Normal values of arterial blood gases : - PaO2 : 70 - 100 mm Hg. - PaCO2 :
35 - 45 mm Hg. - PH : 7.35 - 7.45 - HCO3 : 22 - 27 mEq. - SaO2 : 95 - 99%
5. WHAT IS THE CAUSES OF RESPIRATORY FAILURE
• TYPE I RESPIRATORY
FAILURE
Alveoli Collapse, pulmonary
edema, pneumonia
interstitial tissue Fibrosis
blood vessels embolism and
congestion
• Type ii respiratory failure
Acute
o Depression of respiratory center as in stroke, encephalitis
brain tumors, drugs (opiates)
o Interference in the impulse transmission to respiratory
muscles spinal fracture, Motor neuropathy (GullianBarrie
syndrome]
o Lesions in respiratory muscles: myopathy
o Airway obstruction
Chronic
o Copd
o Restrictive ventilation: massive plural effusion, sever
pulmonary fibrosis
6. HOW TO DIAGNOSE?
• History---- cigarette smoking, goza,
dusty work, alcohol intake, opioids…….
• Clinical picture
• Investigation
7. CLINICAL PICTURE
hypercapnia
hypoxemia
chronic
Acute
chronic
Acute
• Confusion,
• inverted
sleeping
rhythm,
• asterexis.
• Papilloedema.
• Coma.
Confusion,
Drowsines
Convulsio
n
Tachycard
ia,
hypertensi
on.
Finally,
hypotensio
n coma
and death.
1. Mental
dullness,
apathy,
drowsiness.
2. Central
cyanosis.
3. Polycythemia
with plethoric
farcies.
4. Clubbing.
5. Pulmonary
hypertension
and
corpulmonale.
1. Dyspnea &
tachypnea.
2. Central
cyanosis.
3. Tachycardia.
4. Hypertension,
5. Anxiety and
mental
confusion.
6. Final event will
be bradycardia,
7. hypotension,
convulsions,
coma and death.
8. INVESTIGATION
• Laboratory
Abg AND electrolytes
Low O2. ·
High or not CO2. ·
HCO3 high or normal ·
PH varies according to whether it is acute or
chronic condition.
Cbc, lft, rft, blood sugar level
• Radiological
o Chest xray…emphysema
pleural effusion
pneumothorax,
pneumonia
o MRI AND Ct
scan….bronchogenic
carcinoma.
o Brain ct and MRI
• ECG
9. HOW TO DIFFERENTIATE BETWEEN SEVERE LUNG DISEASE
AND NEUROLOGICAL, MUSCULAR OR CHEST WALL
DISEASE?
neurological, muscular or chest wall
disease
severe lung disease
Reduction in consciousness
Neurological examination assess spinal
cord and motor nerve function.
Visual inspection of the chest will
reveal severe deformities (e.g.
kyphosis), obesity or rib fractures
Glasgow Coma Scale
Respiratory examination as look for signs
of COPD as expiratory wheeze, lung
hyperinflation, indrawing, a tracheal tug
and reduced cricosternal distance.
Or other respiratory disease
10. TREATMENT
• 1- Acute cases:
1) Admission to ICU.
2) O2 inhalation in high concentration.
3) Treatment of cause e.g. · Removal of
FB. · Calcium for tetany. ·
Bronchodilators for asthma. · Under
water seal drainage for pneumothorax.
4) Mechanical ventilation +
tracheostomy if treatment of cause
fails.
• 2- Chronic cases:
1) Admission to ICU.
2) Establish patent airway: · Endotracheal tube or
tracheostomy. · Remove obstructive lesions:
Remove FBs.
Eliminate secretions
• Encourage patient to cough
• Liquefaction of sputum e.g. mucolytic
• Expectorants for potassium iodide
• Suction by nasotracheal or orotracheal catheters
3) Respiratory stimulants e.g. doxapram & progesterone.
4) O2 administration: < 35% as O2 apnea may develop with
high concentration.
5) Mechanical ventilation.
6) Treatment of exacerbating factors e.g. · Antibiotics for chest
infection. · Digitalis, diuretics & dilators for HF.
