The virtual absence of stress-ulceration related bleeding in ICU patients receiving prolonged mechanical ventilation without any prophylaxis. A prospective cohort study

Characterization of gastrointestinal bleeding in severely ill hospitalized patients

OBJECTIVE

To characterize the source of bleeding and the prognosis in critically ill patients with upper gastrointestinal hemorrhage that developed while in the hospital.

SETTING

Intensive care units of a large academic tertiary-care center.

DESIGN

Retrospective cohort study.

SUBJECTS

Patients undergoing endoscopy in intensive care units for gastrointestinal bleeding that developed while in the hospital.

MEASUREMENTS AND MAIN RESULTS

Medical records were available for 142 patients. Of these, 66 met the criteria for in-hospital bleeding. Peptic ulcer disease, present in 56% of patients, was the most common bleeding source identified. Of patients with peptic ulcer disease, nine of 37 (24%) had stigmata of recent hemorrhage. Ten patients (15%) received endoscopic hemostasis interventions (eight receiving therapy for bleeding ulcers, two receiving therapy for esophageal varices). The in-hospital mortality rate was 42%. The cause of death was sepsis and/or multiple system organ failure in 21 patients (75%); the gastrointestinal bleeding may have contributed to the onset of sepsis in one of these patients. No patients died directly of gastrointestinal bleeding.

CONCLUSIONS

Critically ill patients who bleed while in the hospital have similar sources of bleeding and rates of endoscopically directed therapy as patients admitted to hospital with bleeding. The mortality rate is very high in patients with bleeding that develops in the hospital, and this is usually a result of systemic disease. These data may help clinicians and patients to estimate the potential benefit of urgent endoscopy in critically ill patients.

Risk factors for clinically important upper gastrointestinal bleeding in patients requiring mechanical ventilation. Canadian Critical Care Trials Group

OBJECTIVE

To evaluate the incidence and risk factors for clinically important upper gastrointestinal bleeding in critically ill patients requiring mechanical ventilation.

DESIGN

In duplicate, blinded adjudicators determined the presence of clinically important gastrointestinal bleeding using a priori criteria, evaluating relevant clinical, laboratory, and diagnostic data. Cox proportional hazards regression analyses were used to examine baseline and time-dependent risk factors for bleeding.

SETTING

Sixteen university-affiliated intensive care units (ICUs) in Canada.

PATIENTS

A total of 1,077 critically ill ICU patients ventilated for at least 48 hrs.

INTERVENTIONS

Patients were randomized to stress ulcer prophylaxis with intravenous ranitidine or nasogastric sucralfate; otherwise, management was at the discretion of the ICU team.

MEASUREMENTS AND MAIN RESULTS

Demographic data included patient characteristics, Acute Physiology and Chronic Health Evaluation II score, and multiple organ dysfunction (MOD) score. Each day in the ICU, physiologic measurements including MOD score, feeding, and other treatment variables were recorded. The significant risk factors for upper gastrointestinal bleeding in the univariable analyses were low platelet count, maximum serum creatinine, maximum MOD score, maximum pulmonary component of the MOD score, maximum hepatic component of the MOD score, maximum renal component of the MOD score, enteral nutrition, and stress ulcer prophylaxis with ranitidine. The only independent predictors of bleeding in the multivariable analysis were maximum serum creatinine (relative risk = 1.16 [95% confidence interval = 1.02-1.32]), enteral nutrition (relative risk = 0.30 [95% confidence interval = 0.13-0.67]), and ranitidine administration (relative risk = 0.39 [95% confidence interval = 0.17-0.83]).

CONCLUSIONS

In critically ill ventilated patients, renal failure was independently associated with an increased risk of clinically important gastrointestinal bleeding, whereas enteral nutrition and stress ulcer prophylaxis with ranitidine conferred significantly lower bleeding rates.

Impact of trauma stress ulcer prophylaxis guidelines on drug cost and frequency of major gastrointestinal bleeding

Trauma patients are routinely prescribed stress ulcer prophylaxis despite evidence suggesting such therapy be limited to patients with identifiable risk factors for bleeding. With surgeons' consensus, we developed and implemented trauma stress ulcer prophylaxis guidelines, and measured the impact of clinical pharmacists on implementing the guidelines and the effect of the guidelines on drug cost and frequency of major gastrointestinal bleeding. Two groups of 150 consecutive patients admitted with multiple trauma were evaluated before and after guideline implementation and stratified by Injury Severity Score (ISS) to minor (ISS < 9) or moderate to severe (ISS > or = 9) trauma groups. The number of patients prescribed stress ulcer prophylaxis, length and cost of this therapy, and number of patients experiencing major gastrointestinal bleeding (decrease in consecutive hemoglobin > or = 2 g/dl in conjunction with coffee-ground emesis, hematemesis, melena, or hematochezia) were measured. All pharmacist interventions pertaining to stress prophylaxis were collected. Fewer patients were prescribed stress ulcer prophylaxis after guideline implementation (105/150, 70% vs 39/150, 26%, p<0.0001), leading to a decrease in total drug cost of $4558. Use decreased more in patients with minor (40/54, 74% vs 9/59, 15%, p<0.0001) than moderate to severe (65/96, 68% vs 30/91, 33%, p<0.0001) trauma. Neither length of therapy nor agent of choice (> 95% cimetidine) differed between groups. Fifteen (38%) of 38 postguideline prophylaxis orders were determined by the pharmacist not to meet guideline criteria. Recommendations to discontinue therapy were accepted in 9 (60%) of 15 instances. The frequency of major gastrointestinal bleeding remained unchanged between groups (1/150 vs 0/150, p=1.0). Implementation of trauma stress ulcer prophylaxis guidelines limiting therapy to patients with risk factors for bleeding led to a 80% decrease in drug cost and did not affect the frequency of major gastrointestinal bleeding.

A randomized, double-blind trial for stress ulcer prophylaxis shows no evidence of increased pneumonia

BACKGROUND

H2-receptor antagonists are commonly used for stress ulcer prophylaxis on intensive care units. However, there is evidence that via the route of an elevated gastric pH, followed by bacterial overgrowth and subsequent tracheal aspiration, pneumonia could occur. In line with this assumption total gastrectomized patients should develop a very high incidence of pneumonia, which is actually not the case. We therefore formulated the hypothesis that stress ulcer prophylaxis with H2-receptor antagonists does not lead to an increased pneumonia rate.

METHODS

A total of 158 patients with mechanical ventilation > or =48 hours of a surgical intensive care unit were randomized to the following groups: A, placebo (n = 57); B, pirenzepine (3 x 10 mg intravenously, n = 44); and C, ranitidine (3 x 50 mg intravenously, n = 57).

RESULTS

The pneumonia rate in ranitidine-, pirenzepine-, and placebo-treated patients is 10 of 57, 10 of 44, and 12 of 57, respectively.

CONCLUSIONS

Pneumonia rate is not adversely affected by H2-receptor antagonists in stress ulcer prophylaxis.

Stress ulcer prophylaxis in medical ICU patients: annual utilization in relation to the incidence of endoscopically proven stress ulceration

OBJECTIVE

To measure changes in the proportion of medical intensive care unit (MICU) patients prescribed pharmacologic stress ulcer prophylaxis therapy over a 4-year period in relation to the incidence of stress-related ulceration detected by endoscopy at our institution.

DESIGN

Retrospective 4-year review of pharmacy and endoscopy databases.

SETTING

A 35-bed MICU.

PATIENTS

Patients (n = 2941) admitted to the MICU for longer than 24 hours, between January 1, 1993, and December 31, 1996, without acute gastrointestinal hemorrhage on admission.

METHODS

Records were reviewed to identify patients prescribed pharmacologic stress ulcer prophylaxis (> 24 h of sucralfate or a histamine2-receptor antagonist [H2RA]), and patients with evidence of stress ulceration during endoscopy.

RESULTS

The number of patients per year receiving stress ulcer prophylaxis significantly (p < 0.001) decreased between 1993 and 1996: 1993, 492/693 (71%); 1994, 478/798 (60%); 1995, 295/670 (44%); 1996, 164/780 (21%). There was no difference between years in the median duration of stress ulcer prophylaxis therapy or the proportion of patients receiving sucralfate versus H2RA therapy. There was no difference (p = 0.91) between years in the annual incidence of definite or possible stress-related ulceration: 1993, 6/693 (0.87%); 1994, 5/798 (0.63%); 1995, 6/670 (0.90%); 1996, 5/780 (0.64%).

CONCLUSIONS

The incidence of endoscopically proven stress-related ulceration has remained unchanged over the past 4 years in our MICU despite significantly fewer patients receiving pharmacologic stress ulcer prophylaxis therapy.

A comparison of sucralfate and ranitidine for the prevention of upper gastrointestinal bleeding in patients requiring mechanical ventilation. Canadian Critical Care Trials Group

BACKGROUND

Critically ill patients who require mechanical ventilation are at increased risk for gastrointestinal bleeding from stress ulcers. There are conflicting data on the effect of histamine H2-receptor antagonists and the cytoprotective agent sucralfate on rates of gastrointestinal bleeding, ventilator-associated pneumonia, and mortality.

METHODS

In a multicenter, randomized, blinded, placebo-controlled trial, we compared sucralfate with the H2-receptor antagonist ranitidine for the prevention of upper gastrointestinal bleeding in 1200 patients who required mechanical ventilation. Patients received either nasogastric sucralfate suspension (1 g every six hours) and an intravenous placebo or intravenous ranitidine (50 mg every eight hours) and a nasogastric placebo.

RESULTS

The patients in the two groups had similar base-line characteristics. Clinically important gastrointestinal bleeding developed in 10 of 596 (1.7 percent) of the patients receiving ranitidine, as compared with 23 of 604 (3.8 percent) of those receiving sucralfate (relative risk, 0.44; 95 percent confidence interval, 0.21 to 0.92; P=0.02). In the ranitidine group, 114 of 596 patients (19.1 percent) had ventilator-associated pneumonia, as compared with 98 of 604 (16.2 percent) in the sucralfate group (relative risk, 1.18; 95 percent confidence interval, 0.92 to 1.51; P=0.19). There was no significant difference between the groups in mortality in the intensive care unit (ICU) (23.5 percent in the ranitidine group and 22.9 percent in the sucralfate group) or the duration of the stay in the ICU (median, nine days in both groups).

CONCLUSIONS

Among critically ill patients requiring mechanical ventilation, those receiving ranitidine had a significantly lower rate of clinically important gastrointestinal bleeding than those treated with sucralfate. There were no significant differences in the rates of ventilator-associated pneumonia, the duration of the stay in the ICU, or mortality.

Current guidelines on stress ulcer prophylaxis

Acute uppergastrointestinal bleeding in intensive care unit (ICU) patients may occur due to peptic ulcer disease, adverse drug effects, gastric tube lesions, acute renal failure, liver failure or stress-induced gastric mucosal lesions. Gastric acid hypersecretion can be observed in patients with head trauma or neurosurgical procedures. Gastric mucosal ischaemia due to hypotension and shock is the most important risk factor for stress ulcer bleeding. Preventive strategies aim to reduce gastric acidity (histamine H2 receptor antagonists, antacids), strengthen mucosal defensive mechanisms (sucralfate, antacids, pirenzepine) and normalise gastric mucosal microcirculation (sucralfate, pirenzepine). However, the most important prophylactic measure is an optimised resuscitation and ICU regime aiming to improve oxygenation and microcirculation. All drugs approved for stress ulcer prophylaxis in Europe (H2 antagonists, antacids, pirenzepine, sucralfate) have been shown to be effective in prospective controlled randomised trials. However, due to insufficient clinical data, prostaglandins and omeprazole cannot be recommended for this use. Stress ulcer prophylaxis is indicated only in patients at risk, and not in every ICU patient. The selection of drugs today depends not only on efficacy but also on possible adverse effects and on costs. In this regard, the most cost-effective drug is sucralfate. The clinical relevance of nosocomial pneumonia due to gastric bacterial overgrowth has decreased during the past decade due to several changes in the management of critically ill patients.

Nursing care of the mechanically ventilated patient in ITU: 1

The mechanically ventilated patient often represents the ultimate in vulnerability and demands the highest standards of nursing care. Not only may the patient be unconscious but also the artificial airway is an unnatural invasion of the most innate physiological mechanism--breathing, and the nurse must safeguard this during all aspects of care. Nursing these patients is immensely satisfying and varied. It ranges from caring for the patient's activities of daily living to carrying out the highly technical and invasive monitoring and interventions which require specialist knowledge and skills. This article, the first in a two-part series, covers the types of ventilation, suction therapy, oral and eye care, elimination, body position, physiotherapy and the physiological effects of mechanical ventilation.