Hoover sign Explanation in COPD case

At first you should know that there are 2 signs named for Charles Franklin Hoover :
1-Hoover's sign of leg paresis.
2-Hoover’s sign in pulmonology which we will take about ;
It refers to inward movement of the lower rib cage during inspiration, implying a flat, but functioning, diaphragm, often associated with COPD.
COPD, and more specifically emphysema, often lead to hyperexpansion of the lungs due to air trapping. The resulting flattened diaphragm contracts inwards instead of downwards, thereby paradoxically pulling the inferior ribs inwards with its movement.

This case for A 70-year-old man with a 70 pack-year history of smoking was referred to the emergency department for an exacerbation of chronic obstructive pulmonary disease (COPD).

On examination, he breathed through pursed lips and had paradoxical indrawing of the lower rib cage margin with inspiration (Hoover sign)(Figure 1A),A chest radiograph showed distension of the lungs and flattening of the diaphragm(Figure 1B).

See this video:

Simple Terms to learn about effect of drugs on CNS

- Sedation : Reduction of anxiety
- Addiction : The state of response to a drug whereby the drug taker feels compelled to use the drug and suffers anxiety when separated from it
- Anesthesia : Loss of consciousness associated with absence of response to pain
- Anxiolytic : A drug that reduces anxiety, a sedative
- Dependence : The state of response to a drug whereby removal of the drug evokes unpleasant, possibly life-threatening symptoms, often the opposite of the drug's effects
- Hypnosis : Induction of sleep
- REM : sleep Phase of sleep associated with rapid eye movements; most dreaming takes place during REM sleep
- Tolerance : Reduction in drug effect requiring an increase in dosage to maintain the same response

Trousseau sign of latent tetany

Trousseau’s sign presents as carpopedal spasm occurring after a few minutes of inflation of a sphygmomanometer cuff above systolic blood pressure "about 3 minutes inflate of cuff >SBP". Occlusion of the brachial artery causes flexion of the wrist and metacarpophalangeal joints, hyperextension of the fingers, and flexion of the thumb on the palm, producing the characteristic posture called main d’accoucheur (The Figure). Trousseau’s sign is
thought to be both sensitive and specific for hypocalcemic tetany. In addition to the obvious visual manifestations, patients with a positive Trousseau’s sign may also experience paresthesia of the fingers, muscular fasciculations or twitches of the fingers, and a sensation of muscular cramping or stiffness.

Pathophysiology:

The proposed mechanism for Trousseau’s sign is increased excitability of the nerves in the arm and forearm, ostensibly caused by hypocalcemia, which, in turn, causes the muscular contractions. These conditions are exacerbated by ischemia produced by the sphygmomanometer, resulting in the twitching that defines the sign.