What is paroxysmal nocturnal dyspnoea (PND)
PND(Paroxysmal Nocturnal Dyspnoea) is the sudden development of dyspnoea during the
early hours of night occurs two three hours after retiring to bed. The patient
awakens from sleep due to feeling of severe suffocation and choking sensation.
After getting up from bed the patient with PND either sits in bed with legs hanging
by the side of bed or may rush to the open window with the hope that cool air
will relieve his symptoms.
This
may be accompanied with dry repetitive cough due to interstitial oedema. Here
the alveoli are free of oedema.
This
attack may progress and severe sweating can occur along with dyspnoea and
subsides in 30 minutes. Sometimes it may progress to acute pulmonary oedema.
Significance
of PND
PND
occur due to acute left heart failure can be LAF or LVF (LAF- left atrial
failure, LVF – left ventricular failure. Acute onset dyspnoea with wheeze and
repeated productive cough are seen in cardiac asthma. It is characterised by
wheeze due to bronchospasm which is more at night. Acute pulmonary oedema is
the severe stage of cardiac asthma with leaking of fluid into the alveoli.
Causes
of PND
PND
is caused by left atrial or left ventricular failure
Clinical
examination findings in PND
1.
Patient is usually anxious
and pale with sweating and air hunger
2.
Central cyanosis may be
present
3.
Tachycardia is present
4.
Blood pressure may be high
5.
Jugular venous pressure is
elevated
6.
S3 gallop may occur
7. Auscultation of lung filed
reveal vesicular breath sound with prolonged expiration. Rhonchi and creps may be
heard.
