Stress-related Disorders/Surgical Stress

Introduction
Psychological stress may cause ordinary peptic disease but stress ulcer is different.

Q. What is Stress ulcer?
A single or multiple fundic mucosal ulcers which often gives upper gastrointestinal bleeding developed during the severe physiologic stress of serious illness.

see also psychological stress (medicine)  for more details.

Q.Ordinary peptic ulcers and Stress ulcers?

Ordinary peptic ulcers are found commonly in the “gastric antrum and the duodenum” whereas Stress ulcers are found commonly in “fundic mucosa and can be located anywhere within the stomach and proximal duodenum”.

''see also peptic ulcer for more details. ''

''see also Timeline of peptic ulcer disease and Helicobacter pylori for more details. ''

Q. Who can get Stress ulcers?

 * Those patients who are on respirators (artificial ventilator) and who have multi-system disorders (i.e. many organs malfunction).


 * Those patients with a past history of peptic ulcer or upper gastrointestinal bleeding.
 * Stress ulceration occurs in patients with major injury or illness, who have undergone major co-morbidity.
 * These are some types of acute ulcers, which develop in critically ill patients under intensive lifesaving management or after burns.
 * Focal acutely developing gastritis mucosal defects are a well-known complication of therapy with NSAIDs. Alternatively, they may appear after severe physiologic stress, whatever its nature – hence the term stress ulcers.

Example:
 * Elderly patients in a surgical intensive care unit (ICU) with heart and lung disease have a high postoperative prevalence of stress ulcers.
 * Patients in a medical ICU, particularly those who require respirators, are at high risk of development of stress ulcers.

It is possible that poor mucosal oxygenation, differences in acid-base balance, and elevated circulating corticosteroids may contribute to the formation of these ulcers.

Diagnosis
Q. When is stress ulcer suspected?


 * Stress ulcer is suspected when there is upper gastrointestinal bleeding in appropriate clinical setting.

Example:
 * When there is upper gastrointestinal bleeding in elderly patients in a surgical intensive care unit (ICU) with heart and lung disease.
 * When there is upper gastrointestinal bleeding in patients in a medical ICU who require respirators.

Q. How stress ulcer can be diagnosed?


 * After the initial management of gastrointestinal bleeding, the diagnosis can be confirmed by upper GI endoscopy.

The site of ulcerations
The ulcerations may be superficial and confined to the mucosa, in which case they are more appropriately called erosions, or they may penetrate deeper into the submucosa. The former may cause diffuse mucosal oozing of blood, whereas the latter may erode into a submucosal vessel and produce frank hemorrhage.

Lesion of stress ulcers
The characteristic lesions may be multiple, superficial mucosal erosions similar to erosive gastroduodenitis. Occasionally, there may be a large acute ulcer in the duodenum (Curling’s ulcer).

Generally, there are multiple lesions located mainly in the stomach and occasionally in the duodenum. They range in depth from mere shedding of the superficial epithelium (erosion) to deeper lesions that involve the entire mucosal thickness (ulceration).

Stress Ulcer formation
The pathogenic mechanisms are similar to those of erosive gastritis.”

Q. How and why Stress ulcer is developed?

The pathogenesis of stress ulcer is unclear but probably is related to a reduction in mucosal blood flow or a breakdown in other normal mucosal defense mechanisms in conjunction with the injurious effects of acid and pepsin on the gastroduodenal mucosa.

Prophylaxis
Prevention of this condition is far better than trying to treat it once it occurs.

'''Q. How to prevent its development? ''' In recent years by using Ranitidine (H2-receptor antagonist)[] and nasogastric administration of sucralfate has reduced the incidence of stress ulceration.

Management
The principles of management are the same as for the chronic ulcer.

The steps of management are similar as in erosive gastritis.

Treatment
Endoscopic means of treating stress ulceration may be ineffective and operation required. It is believed that shunting of blood away from the mucosa makes the mucous membrane ischaemic and more susceptible to injury.

Treatment of stress ulceration usually begins with prevention. Careful attention to respiratory status, acid-base balance, and treatment of other illnesses helps prevent the conditions under which stress ulcers occur. Patients who develop stress ulcers typically do not secrete large quantities of gastric acid; however, acid does appear to be involved in the pathogenesis of the lesions. Thus it is reasonable either to neutralize acid or to inhibit its secretion in patients at high risk.

In case of severe hemorrhagic or erosive gastritis and stress ulcers, a combination of antacids and H2-blockers may stop active bleeding and prevent re bleeding. In selected patients, either endoscopic therapy or selective infusion of vasopressin into the left gastric artery may help control the hemorrhage.

Selected Readings

 * Cheung, L. Y. Pathogenesis, prophylaxis and treatment of stress gastritis. Am. J. Surg. 156:437, 1988.
 * Craven, D. E., et al. Risk factors for pneumonia and fatality in patients receiving continuous mechanical ventilation. Am. Rev. Respir. Dis. 133:792, 1986.
 * Driks, M. R., et al. Nosocomial pneumonia in intubated patients given sucralfate as compared with antacids or histamine type 2 blockers. N. Engl. J. Med. 317:1376, 1987.
 * DuMoulin, G. C., et al. Aspiration of gastric bacteria in antacid-treated patients: A frequent cause of postoperative colonisation of the airway. Lancet 1:242, 1982.
 * Lamothe, P. H., et al. Comparative efficacy of cimetidine, famotidine, ranitidine, and Mylanta in postoperative stress ulcers: Gastric pH control and ulcer prevention in patients undergoing coronary artery bypass graft surgery. Gastroenterology 100:1515, 1991.
 * Priebe, H. J., et al. Antacid versus cimetidine in preventing acute gastrointestinal bleeding: A randomized trial in 75 ill patients. N. Engl. J. Med. 302:426, 1980.
 * Shuman, R. B., Schuster, D. P., and Zuckerman, G. R. Prophylactic therapy for stress ulcer bleeding: A reappraisal. Ann Intern. Med. 106:562, 1987.
 * Tryba, M. Stress bleeding prophylaxis with sucralfate: Pathophysiologic basis and clinical use. Scand. J. Gastroenterol. [Suppl. 173] 25:22, 1990.