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GERD%20and%20Asthma

  GERD Symptoms
  Two mechanisms account for the breathing problems associated
  with GERD. One is acid injury of the lining cells of the
  throat and the airways. The stomach lining is specifically
  designed to tolerate an acid environment. By contrast, the
  esophagus is not nearly as tolerant, resulting in episodes of
  anterior chest discomfort that we call heartburn. The throat
  (including the vocal cords) and the airways of the lungs are
  even less able to stand up to the acidity of gastric
  secretions. Swelling around the vocal cords produces not only
  a hoarse voice but also spasm of the cords and a frightening
  narrowing of the air passage into the lungs. This may result
  in difficulty taking air into the lungs and a characteristic
  sound during inspiration (inhaling), called stridor.
  Irritation of the nerve receptors in both the throat and the
  airways also explains the persistent cough often found in
  patients with GERD.
   The other mechanism of GERD that leads to breathing
  difficulties is probably one that is designed to be
  protective. When acid escapes the stomach by backing up into
  the esophagus, a nerve reflex is stimulated, perhaps signaling
  the airways of the risk of subsequent acid reflux into the
  lungs. In order to protect against this event, the airways
  narrow. While this likely protects against acid aspiration
  into the lung, it also produces shortness of breath due to the
  constricted airway.
   
  Diagnosing GERD in Asthmatics
  We suspect that as many as 80 percent of asthmatics have at
  least mild acid reflux disease. In the majority of asthmatics,
  the reflux is mild and produces minimal symptoms. How can we
  decide which patients are at particular risk for clinically
  important acid reflux and require more testing? I rely
  primarily on two clues. First, if a patient has asthma that is
  not responding as expected to medical therapy, I ask if they
  suffer from heartburn or acid indigestion. I do this
  recognizing that half of the patients who have proven
  GERD-related lung symptoms answer no to both questions.
  Although these patients have acid reflux disease, the symptoms
  can occur in the airways and yet be absent in the
  gastrointestinal sytstem. The second major clue is nocturnal
  awakening with any combination of wheezing, coughing, or a
  choking sensation. Many of these patients describe airway
  tightness focused in the throat rather than the chest. This
  probably reflects the intense inflammation and spasm of the
  vocal cords that typifies GERD, but not bronchial asthma.
   
Ora