Fever in ICU

1. Fever in ICU Dr. MarwanJabrAlwazzeh Assoc. Prof. of Medicine Consultant Internist/Infectious Diseases University of Dammam 02/04/2012

2. Why Fever In ICU? • Key Problem Requires Thoughtful Evaluation and Treatment. • Increasing health care costs. • Exposes patients to sometimes unnecessary invasive diagnostic procedures • Inappropriate use of antibiotics that promoting emergence of resistant microbes.

3. When we say “fever” in the ICU patient? • Definition of fever is Arbitrary. • Society of Critical Care Medicine and Infectious diseases society of America >38.3 °C (100.4°F). • Lower threshold for surgery and immunocompromised patients >38.0 °C (100.4°F).

4. Pathophysiology of Fever

5. Significance of Fever • Enhancing the resistance to infection • Temperature elevation enhances immune function by: • Increased antibody production • Promoting T-cell activation • Increased cytokine production • Stimulates neutrophil and macrophage function

6. Significance of Fever • Beneficial effects of hot baths and malarial fevers in treating syphilis. • In Gram negative bacteremia, a positive correlation between maximum temperature on the day of bacteremia and survival. • Some pathogens such as Streptococcus pneumoniaeare inhibited by febrile temperatures.

7. Significance of Fever • Most patients should not routinely receive empiric antipyretic medication. • Acute hepatitis may occur in ICU patients with reduced glutathione reserves (alcoholics, malnourished, etc.) who have received regular therapeutic doses of acetaminophen. • Aggressively treating fever in critically ill patients may lead to a higher mortality rate.

8. Deleterious Effects Of Fever • ↑↑ Cardiac Output • ↑↑ Oxygen Consumption (approx 10%/°C) • ↑↑ Carbon Dioxide Production • ↑↑ Energy Expenditure

9. Accuracy of methods used for measuring temperature • Most accurate • Pulmonary artery thermistor • Urinary bladder catheter thermistor • Esophageal probe • Rectal probe • Other acceptable methods in order of accuracy • Oral probe • Infrared ear thermometry • Other methods less desirable • Temporal artery thermometer • Axillary thermometer • Chemical dot Accuracy

10. Recommendations for Measuring Temperature • Axillary, temporal artery, and chemical dot thermometers should not be used in the ICU • Rectal thermometers should be avoided in neutropenic patients • Whatever device chosen should be used in a manner that does not facilitate spread of pathogens by the instrument or the operator

11. Treating Fever per se • Fever should be treated only in patients with: • Acute brain insults. • Limited cardiorespiratory reserve (ie, ischemic heart disease). • Temperature increases above 40°C (104°F)

12. Causes of fever in ICU • Differential diagnosis influenced by patient population • Medical vs. Surgical • Immunocompromised vs. competent • Community vs. Nosocomial • Pediatric vs. Geriatric

13. Causes of fever in ICU

14. Main infectious Causes • Intravascular Devices infection and septicemia • Pulmonary Infections and ICU-Acquired Pneumonia. • Urinary Tract Infections. • Infectious Diarrhea. • Sinus infections. • Surgical Site Infections. • Central Nervous System Infection.

15. Fever In ICU

16. Infectious causesDefinitions

17. Systemic Inflammatory Response Syndrome • Tow or more of the following: • Temperature ≥38 °C or ≤36 °C • Heart rate ≥90 beats/min • Respirations ≥20/min or arterial Carbone dioxide tension (PaCO2) < 32 mm Hg • White blood cell count ≥12,000/mm3 or ≤4000/mm3 or >10% immature [band] forms

18. Systemic Inflammatory Response Syndrome • Often noninfectious etiology found: • Pulmonary embolism • Myocardial infarction • Gastrointestinal bleeding • Acute pancreatitis • Cardiopulmonary bypass

19. Sepsis SIRS with a presumed or confirmed infectious process

20. Severe sepsis • Sepsis with one or more signs of organ failure: • Cardiovascular • Renal • Respiratory • Hepatic • Hematologic • Central nervous system • Metabolic acidosis

21. Septic shock Sepsis-induced hypotension, despite adequate fluid resuscitation, with presence of perfusion abnormalities

22. Infectious Causes • Not all patients with infections are febrile. • 10% of septic patients are Hypothermic. • 35% are normothermicat presentation. • Septic patients who fail to develop a temperature have a significantly higher mortality than febrile septic patients.

23. Afebrile infected patients • Elderly • Open abdominal wounds. • Large burns • Extracorporeal membrane oxygenation (ECMO)‏ • CHF • CRF or End-stage liver disease. • Continuous renal replacement therapy • Taking anti-inflammatory or antipyretic drugs 

24. How can I Diagnose Infection in absence of fever? • Unexplained hypotension • Tachycardia • Tachypnea • Confusion • Rigors • Skin lesions • Respiratory manifestations • Oliguria • Lactic acidosis • Leukocytosis • Leukopenia • Immature neutrophils (i.e., bands) of >10% • Thrombocytopenia

25. When should I be worried? • Immunocopromized patient • Hemodynamic instability • Oliguria • Increasing lactate • Worsening conscious state • Falling platelet counts • Worsening coagulopathy.

26. Intravascular Devices infection and septicemia

27. Intravascular Devices infection and septicemia

28. Catheter-Related Bloodstream InfectionDefinition • A positive catheter culture 15 CFU with concomitant positive blood culture of the same organism. • No other identifiable source of infection.

29. Local Catheter-Related InfectionDefinition • Growth of 15 or more CFU from a catheter specimen by semiquantitative culture. • Local signs of inflammation: erythema, swelling, tenderness, purulent material. • Negative peripheral blood culture.

30. Catheter-Related Bloodstream Infection Approximately 25% of central venous catheters become colonized, and approximately 20-30% of colonized catheters will result in catheter sepsis

31. Suppurative phlebitis • Most often encountered in burn patients or other ICU patients who develop catheter-related infection that goes unrecognized, permitting microorganisms to proliferate to high levels within an intravascular thrombus. • bloodstream infection characteristically persists after the catheter has been removed. • Clinical picture of overwhelming sepsis with high-grade bacteremia or fungemia or with septic embolization.

32. Recommendations for Obtaining Blood Cultures • For patients without an indwelling vascular catheter, obtain at least 2 blood cultures using strict aseptic technique from peripheral sites by separate venipunctures after appropriate skin disinfection. • For patients with an indwelling vascular catheter Obtain 3-4 blood cultures.

33. Recommendations for Obtaining Blood Cultures • For cutaneous disinfection: • 2%chlorhexidinegluconate in 70% isopropyl alcohol • tincture of iodine is equally effective (30 sec. of drying time). • Povidine iodine is an acceptable alternative, but must wait greater than 2 minutes to dry.

34. Recommendations for Obtaining Blood Cultures • The injection port of the blood culture bottles should be wiped with 70-90% alcohol before injecting the blood sample into the bottle. • Most blood culture bottles should not be swabbed with iodine-containing antiseptics. • Draw 20-30ml of blood per culture. • Label the blood culture with the exact time, date, and anatomic site from which it was taken.

35. Management of fever in ICU • There is no evidence that the yield of cultures drawn from an artery is different from the yield of cultures drawn from a vein. • Catheter Cultures: • Short catheter: tip. • longer catheter: Tip and intracutaneous segment. • Pulmonary artery catheter: Tip and introducer. • It is rarely necessary to culture infusate specimens. • It is rarely necessary to culture infusate specimens.

36. Candidemia • Candida species are constituents of the normal flora in about 30% of all healthy people. • Antibiotic therapy increases the incidence of colonization by up to 70%. • Candida Infection should be considered in febrile ICU patients who have been in the ICU for ≥10 days and have received multiple courses of antibiotics.

37. Candidemia • Although candiduria may be observed in up to 80% of patients with systemic candidiasis, candidemia from a urinary tract source is extremely rare. • galactomannan and beta-D-glucan for aspergillosis and Candida may be useful as supportive evidence of infections but may be most useful to exclude invasive fungal infection, given their high negative predictive value.

38. Catheter Related Blood Stream InfectionCVC Insertion Bundle • Hand hygiene. • Maximal barrier precautions. • Chlorhexidine skin antisepsis. • Optimal catheter site selection, with avoidance of using the femoral vein for central venous access in adult patients. The Canadian Collaborative, Safer Healthcare Now

39. Catheter Related Blood Stream InfectionCVC Maintenance Bundle • Daily review of line necessity and prompt removal of unnecessary lines. • Dedicated lumen for total parenteral nutrition (TPN). • Access the CVC lumens aseptically. • Checking entry site for inflammation with every change of dressing. The Canadian Collaborative, Safer Healthcare Now

40. Pulmonary Infections and ICU-Acquired Pneumonia

41. Recommendations for Evaluation of Pulmonary Infections • All radiographs should be performed in an erect sitting position, during deep inspiration if possible. • The absence of infiltrates, masses, or effusions does not exclude pneumonia, abscess, or empyema. • Obtain one sample of lower respiratory tract secretions for direct examination and culture before initiation of or change in antibiotics.

42. Recommendations for Evaluation of Pulmonary Infections • Isolation of enterococci, viridans streptococci, coagulase-negative staphylococci, and Candidaspecies should rarely if ever be considered the cause of respiratory dysfunction. • Quantitative cultures can provide useful information in certain patient populations when assessed in experienced laboratories.

43. Ventilator Bundle • Elevate the Head of the bed to 30-45 degrees. • Peptic ulcer disease prophylaxis. • Deep venous thrombosis prophylaxis. • Provide mouth care every 2-4 hours. • Sedation vacation every day. • Repeated evaluation of the patient’s readiness to be weaned from the ventilator.

44. Urinary Tract Infection

45. Urinary Tract Infection • Pyuria may be absent in patients with catheter-associated urinary tract infection and, even if present, is not reliably predictive of infection or associated with symptoms referable to the urinary tract. • The rapid dipstick tests, which detect leukocyte esterase and nitrite, are unreliable tests in the setting of catheter-related urinary tract infection.

46. Urinary Tract Infection • The concentration of urinary bacteria or yeast needed to cause symptomatic urinary tract infection or fever is unclear. • Bacteriuria with ≥ 105 CFUs of bacteria per milliliter of urine during bladder catheterization was associated with a 2.8-fold increase in mortality.

47. Urinary Tract Infection • Patients with urinary catheters in place should have urine collected from the sampling port and not from the drainage bag. • Urine should be transported to the laboratory and processed within one hour to avoid bacterial multiplication. • Gram stains of centrifuged urine will reliably show the infecting organisms

48. UTI bundle • Use sterile technique at insertion • Perform a daily reviewof the need for the urinary catheter. • Provide perineal care on a daily basis and after every bowel movment. • Keep the drainage bag lower than patient's bladder at all times. • Secure all catheters

49. Infectious Diarrhea

50. C.Difficileassociated diarrhea • May occur with any antibacterial agent, but the most common causes are clindamycin, cephalosporins, and fluoroquinolones. • some patients with C.difficileespecially those who are postoperative, may present with ileus or toxic megacolon or leukocytosiswithout diarrhea.