Transcript
Chapter 37: Multiple Organ Dysfunction Syndrome
Critical Thinking Checkpoint Case Studies
Mr. F., a 75-year-old male, was admitted to the high-acuity unit with a diagnosis of pneumonia. He was placed on IV hydration and antibiotics. Twenty-four hours later, he complains of shortness of air and difficulty breathing. His blood pressure is 80/60 mm Hg, pulse 125 bpm, respirations 30 bpm, temperature 102.4°F (39°C). A chest x-ray revealed diffuse bilateral infiltrates. Arterial blood gas results on 2 L nasal cannula: pH 7.45 PaCO2 45, PaO2 44, SaO2 82%. He is intubated and transferred to the ICU. Twenty-four hours later, he remains intubated. Morning serum laboratory results reveal the following:
lactate, 5.2 mmol/L; glucose 320 mg/dL; Cr 2.8 mg/dL; WBC 25,000; Hct 22.4%; Hb 7.5; Platelets 86,000.
His urine output the past 24 hours was 400 mL.
This activity contains 5 questions.
1. What are Mr. F.'s risk factors for developing SIRS?
Answer: The only risk factor known from the data given is his age, greater than 65 years. The nurse should review the patient's medical history to determine patient-related risk factors such as his baseline organ function, alcohol abuse, malnutrition, and history of immunosuppressive conditions (cancer, AIDS). The nurse should review the patient's hospital course over the past 48 hours to determine whether there was a delay or inadequate resuscitation and to ascertain the possibility that this patient could have another source of an inflammatory-infectious process (such as a urinary tract infection).
2. What conditions does Mr. F. have that meet the criteria for SIRS?
Answer: Temperature greater than 38°C, heart rate greater than 90/min., respiratory rate greater than 20/min., WBC greater than 25,000
3. Based on the data given, what organ systems appear to be in failure? Give data to support your answer.
Answer: Respiratory failure: He requires mechanical ventilation in ICU; renal failure: elevated Cr; hematology: low platelets.
4. Do you believe Mr. F., now in the ICU, has MODS? Explain your answer.
Answers: Mr. F. has MODS. MODS is defined as a dysfunction of two or more organ systems and develops after an acute life-threatening disruption by homeostasis.
5. What is the pathophysiologic basis of MODS in this patient? How could he have a pulmonary infection upon admission to the high-acuity unit and 48 hours later have MODS?
Answer: Mr. F. had a localized inflammatory-infectious process in his lungs that progressed to a state of uncontrolled systemic inflammation. The respiratory system is the main organ system affected in MODS. The lungs are particularly at risk for dysfunction when there is a loss of the epithelial barrier. Loss of this barrier, as in sepsis, allows leakage of proteins to and from the lungs. Proinflammatory mediators are released and cause pulmonary edema and vasodilation.
