Stress Ulcer Tianjin medical university general hospital Songtao shou
sex :male age: 75y chief complaints : cough,gasp and spitting for 10 days,fever for 3 days. lethargy for 1 day . past history : COPD for 10 years. After admission to ICU,we found his stools were dark stools. ( no history of peptic ulcer.) Symptoms :cough, expectoration, gasp and fever,without abdominal pain . laboratory examination : ABG:pH 7.40,PaO 2 50mmHg ,PaCO 2 80mmHg Chest x-ray : Diagnosis : COPD , respiratory failure, pneumonia
It is the acute changes confined to the gastric mucosa under the condition of physiologic or psychological stress.the mucosal lesion and associated clinical bleeding or perforation have been termed SUS.
The major risk factors are respiratory failure, coagulopathy, sepsis, hypotension and hepatic and renal failure.
there is a good relationship between severity of illness (as determined by, for example, APACHE II scores) and incidence of ulceration.
Moreover, the longer a patient in ICU, the more likely they are to have a GI bleed . Patients who are likely to have a number of these risk factors – burns patients for example (ventilated, hypotensive, coagulopathic), are more likely to have ulceration and bleeding.
Pathogenesis of stress ulcer stress ulcer syndrome appears to be mucosa ischemia resulting form splanchnic hypofusion in the setting of physiologic stress and an acid
（ 1 ） mucosa ischemia （ 2 ） H + diffuse to intramucosa （ 3 ） others : acidosis CA Mucosa barrier H + diffuse to intramucosa Blood flow H + pump out ulcer GC stressor Mucosa ischemia
Disproportionate vasoconstrictor response to stress
Neural nor-adrenaline and circulating adrenaline have similar effects on vasoconstriction in gastric mucosal and systemic vascular beds
Renin-angiotensin system and to a lesser degree vasopressin are responsible for the disproportionate response.
The mucosa is compromised by ischemia and attacked (mostly) by acid. It is injured, and, due to the presence of acid, cannot repair itself (hostile environment). The use of external agents to neutralize acid resolves this problem.
easy to heal ； bleeding and perforation are seldom
Differences between PU and SU Endoscopic barium meal and endoscope diagnose Abdominal pain, Bleeding and Perforation are unusual Abdominal pain,perforation and bleeding Signs and symptoms Multiple Single or two Ulceration cardia ,fundus and body antrum Location acute chronic Attack SU PU
The mucosa plica in the gastric body is smooth.
Before making gastroscope,we have to fulfill the stomach with enough air,so under gastroscope the mucosa is very smooth.pylorus is round and always in contraction.
Patients who do not have one of the six major risk factors do not require treatment.
Patients in shock, sepsis, respiratory, hepatic or renal failure, or who have a coagulopathy, who are admitted to intensive care, should all be given stress ulcer prophylaxis.
The goal of therapy Stress ulcers are not deep craters like those seen in peptic ulcer disease,but are superficial erosions confined to the surface of the mucosa.Therefore, the goal of therapy is not so much to prevent their appearance but to limit the incidence of troublesome bleeding.
Ranitidine and sucralfate are the most effective agents. Ranitidine is associated with a lower incidence of clinically significant bleeding, sucralfate with a lower incidence of pneumonia.
Principle of enteral feeding 1. To neutralize gastric pH(to dilute the relatively acid enviroment) 2. To provide the cells of the gastric mucosa with a nutrient.the cells may use luminal nutrients as a source of energy to produce the protective surface lining. 3. It solves the problems of nutrition and stress ulcer prophylaxis.
SUS are often viewed as a primary illness instead of a signal for mucosal ischemia . The misconception has created some confusion about the appropriate therapy for stress ulcers and specifically about the role of gastric acid suppression therapy.through the chapter ,we know stress ulcers are a manifestation of mucosa ischemia and NOT a manifestation of gastric hyperacidity.