Cough

Acute cough is of less than three weeks duration and a chronic cough lasts more than eight weeks.

One of the most frequent causes for medical consultation.

Cough results following stimulation of receptors in the respiratory tract with sudden inspiration occurring and then tightening of the chest and abdominal muscles against the closed glottis with a sharp rise in intrathoracic pressures of up to 300 mmHg.

Following this the glottis suddenly opens leading to the rapid expiratory flow and characteristic noisy expiration, termed cough.

Cough that occurs in a series is referred to as a cough bout.

A weak or ineffective cough is associated with serious pulmonary infections.

Viral infections of the upper respiratory tract are the most common cause of acute cough.

Acute cough, is associated with acute upper and lower viral and bacterial respiratory tract infections, predominately, but exacerbations of pre-existing conditions may occur.

Chronic cough is related to smoking, upper airway cough syndrome, bronchial asthma, non-asthmatic eosinophilic bronchitis and gastrointestinal reflux disease.

Most common causes of chronic cough are postnasal drip, asthma and gastroesophageal reflux.

Chronic cough defined as a cough of 3 weeks or more in duration.

Induced rib fractures occurs primarily in women and is associated with chronic rather than acute coughing.

In patients with chronic cough approximately one-half of patients have more than one cause for cough.

Longstanding process may indicate the presence of upper airway disease, gastroesophageal reflux disease and parenchymal lung disease.

Classification includes acute cough with duration of less than three weeks, subacute cough 3-8 weeks or chronic cough grade in eight weeks (Prather MR et al).

It may be a voluntary act or in unsuppressable reflex.

Cough is an essential protective reflex aimed at clearing the larynx, trachea, and bronchi of mucus, irritants, foreign particles, and micro organisms.

Call attempts to free the airways and preventing infection.

Most common cause of acute cough is a self limited process, a viral upper respiratory infection, although it may be caused by a serious condition such as congestive heart failure, lung cancer, pneumonia, or pulmonary embolism.

Subacute cough most frequently represents persistence of an acute respiratory infection involving either the upper or lower airways.

Associated with angiotensin-converting enzyme inhibitors.

Chronic cough most commonly caused by gastroesophageal reflux disease, asthma, and chronic sinusitis/post nasal drip.

Non-asthmatic eosinophilic bronchitis may be associated with chronic cough and is defined by cough, with eosinophils in the sputum, but not associated with dyspnea, wheezing, airflow obstruction or airway hyperactivity.

Pertussis can be associated with sub acute and chronic cough.

Severe cough may cause subconjunctival bleeding, rib fractures, incontinence of urine, hernias, syncope, intracranial hemorrhage and dissection of the vertebral artery and insomnia (Irwin RS).

Cough can be severe, violent and repetitive and can be associated with tissue injury which may aggravate an underlying process.

Cough induced complications include: involvement of the upper airways, chest wall and thorax, abdominal wall, heart and aorta, CNS, eye, gastrointestinal tract, stress incontinence, and emotional and psychological harm.

Cough complications include cartilage fracture intercostal lung herniation, diaphragmatic rupture, spontaneous pneumothorax or pneumomediastinum, hemothorax, and rupture of an intercostal artery.

Increase in intraabdominal pressure during coughing can worsen inguinal, umbilical, and abdominal hernias.

Rupture of a normal spleen can occur spontaneously from severe cough.

Cough syncope has been reported with the loss of consciousness occurring immediately after cough, especially after prolonged bouts of violent coughing.

Cough syncope is more common in males who are middle-age, obese, with COPD and who smoke.

Cough or sneeze syncope is classified as situational syncope along with syncope following G.I. stimulation or micturition as a form of reflex syncope similar to vasovagal faint.

Coughing acutely increases intrathoracic pressure, lowers  venous return and cardiac output.

With coughing patient’s blood pressure drops excessively where is expected heart rate compensatory  acceleration does not occur.

Rib fractures due to severe cough can be diagnosed by the presence of chest pain occurring after the onset of coughing, x-ray changes of rib fracture, absence of trauma, metastatic disease or other obvious explanation for a fracture.

Patients with rib fractures  may have pleuritic chest pain or chest wall tenderness on palpation.

Cough can be associated with poorly localized muscle pain, especially chest pain.

Women predominate in cough induced rib fractures.

Cough induced fractures are very uncommon.

Bruising or puncture of long but I really is could cause pleural effusion, pneumothorax, hemothorax, and even lung herniation.

Rapid increase in intrathoracic an intra-abdominal pressure during coughing increases central venous and intracranial pressure and triggers a sudden, sharp, stabbing, moderate to severe headache of short duration from one second to 30 minutes.

Unilateral headache is not uncommon.

Most patients with cough induced headache are in their 40s or 50s amd the prevalence is up to 1.2% in headache clinics.

Primary cough headache must be ascertained by neuroimaging because 40% of these patients have an underlying structure etiology, most located in the posterior fossa.

Such headaches are often due to Chiari type 1 malformation, a herniation of the cerebellar tonsils through the foraminal magnum.

Cough induced headache is mediated by transient increase in intracranial CSF pressure as a result of obstruction and the symptom can be reproduce by a modified Valsalva test.

Chronic cough is associated with subsequent myocardial infarction.

Chronic cough is an independent predictor of MI with significant odds ratio of 1.6-1.8, respectively.

A focal neurological deficit induced by coughing is rare but is well-established: cervical artery dissection is the most common reason, when arterial wall layers becomes separate and blood connects between them.

Chronic cough is the leading symptom of gastrointestinal reflux disease and can occur even without concomitant gastrointestinal symptoms.

GERD is one of the major causes of chronic cough.

Cough leading to secondary GERD is also well-established.

In patients with asthma, nearly half of all coughs are associated with a reflux episode, seven times more often than the opposite.

Rapidly increasing abdominal pressure associated with coughing, sneezing, laughing or exertion can cause involuntary leakage from the urethra and signifies stress urinary incontinence.

Stress urinary incontinence affects 3.5% of women and in 24-54% of affected women chronic cough is a risk factor.

Chronic cough can lead to impaired quality of life with depression, anxiety, insomnia and frustration.