The MRC breathlessness scale suggests five grades of dyspnea based on the circumstances and severity in which it arises. Blood tests
A number of labs may be helpful in determining the cause of shortness of breath. D-dimer, while useful to rule out a pulmonary embolism in those who are at low risk, is not of much value if it is positive, as it may be positive in a number of conditions that lead to shortness of breath. A low level of brain natriuretic peptide is useful in ruling out congestive heart failure; however, a high level, while supportive of the diagnosis, could also be due to advanced age, kidney failure, acute coronary syndrome, or a large pulmonary embolism. Imaging
A chest x-ray is useful to confirm or rule out a pneumothorax, pulmonary edema, or pneumonia. Spiral computed tomography with intravenous radiocontrast is the imaging study of choice to evaluate for pulmonary embolism. Treatment
The primary treatment of shortness of breath is directed at its underlying cause. Extra supplemental oxygen is effective in those with hypoxia; however, this has no effect in those with normal blood oxygen saturations. Physiotherapy
Individuals can benefit from a variety of physical therapy interventions. Persons with neurological/neuromuscular abnormalities may have breathing difficulties due to weak or paralyzed intercostal, abdominal and/or other muscles needed for ventilation. Some physical therapy interventions for this population include active assisted cough techniques, volume augmentation such as breath stacking, education about body position and ventilation patterns and movement strategies to facilitate breathing.
Predisposition is easily aggravated by any of the following: poor motility of the digestive tract, retroperitional tumors, loss of appetite, malabsorption, cachexia, exaggerated lumbar lordosis, visceroptosis, abdominal wall laxity, peritoneal adhesions, abdominal trauma, rapid linear adolescent growth spurt, weight loss, starvation, catabolic states (as with cancer and burns), and history of neurological injury.The acute form of SMA syndrome develops rapidly after traumatic incidents that forcibly hyper-extend the SMA across the duodenum, inducing the obstruction, or sudden weight loss for any reason. Causes include prolonged supine bed rest, scoliosis surgery, left nephrectomy, ileo-anal pouch surgery.SMA syndrome is usually difficult to differentiate with anorexia nervosa. Patients with SMA syndrome can be hindered restoring weight in those with anorexia nervosa. Diagnosis
Diagnosis is very difficult, and usually one of exclusion. SMA syndrome is thus considered only after patients have undergone an extensive evaluation of their gastrointestinal tract including upper endoscopy, and evaluation for various malabsorptive, ulcerative and inflammatory intestinal conditions with a higher diagnostic frequency. Diagnosis may follow X-ray examination revealing duodenal dilation followed by abrupt constriction proximal to the overlying SMA, as well as a delay in transit of four to six hours through the gastroduodenal region. Standard diagnostic exams include abdominal and pelvic computed tomography (CT) scan with oral and IV contrast, upper gastrointestinal series (UGI), and, for equivocal cases, hypotonic duodenography.