Cardiovascular Infections

• What is the email address provided in the study material?

  [e-mail]
• What immune responses are involved in the host response to bloodstream infection?

  Both the innate and adaptive immune response
• What types of phagocytic cells are involved in the immune response?


  • Neutrophils
  • Macrophages
  • Eosinophils
• What does CRP stand for in the context of the immune response?


  1. reactive protein
• What is bacteraemia?


  Presence of viable bacteria circulating in the bloodstream
• How can bacteraemia be detected?


  By isolating bacteria from blood cultures
• How long can bacteraemia be detectable after infection?


  12 – 48 hours
• What activities can lead to transient bacteraemia?


  Dental treatment, invasive medical procedures, IV drug abuse, and trauma
• What is a common consequence of brushing your teeth?

  It can result in transient bacteraemia
• How is bacteraemia typically characterized?


  Usually transient, self-limiting, and inconsequential
• What can bacteraemia trigger in the immune system?


  It can trigger an immune response that may result in sepsis
• What is the definition of septicaemia?


  A life-threatening condition where the body's response to infection can result in organ dysfunction and tissue damage
• What can develop from an overreactive systemic immune response in sepsis?


  Septic shock, where blood pressure drops dangerously low
• What are the symptoms of sepsis?


  • Extremes of temperature
  • Increased breathing/heart rate
  • Confusion
  • Discoloured skin
• How many people does sepsis kill globally every year?


  6 million people
• How many people does sepsis kill in the UK every year?

  52,000
• What is the inflammatory response in sepsis according to Reinhart et al. 2012?


  • Simplified diagram of the sepsis immunological cascade
• What is the target saturation for septicemia treatment?


  Target saturation >94%
• What is the recommended flow rate for oxygen delivery in septicemia?


  High flow 15 litres/min via non-rebreather mask
• What is the first step in diagnosing septicemia?


  At least one set of blood cultures
• What type of antibiotics are used in septicemia treatment?

  Broad-spectrum antibiotics covering gram-positive, gram-negative, and anaerobes
• What solution is mentioned for septicemia treatment?

  Hartmann's solution
• What should be checked in septicemia treatment?


  Serum lactate levels
• What may be required for septicemia treatment?


  Urinary catheter
• What is the mortality rate within 24 hours for septicemia?


  52.8%
• What is the mortality rate after 24 hours for septicemia?


  97.6%
• Why is rapid diagnosis key in septicemia?


  To improve treatment outcomes and reduce mortality rates
• What are the most common bloodstream pathogens and their associated mortality rates?


  1. CoNS: 15.8% BSI per 10,000 admissions
  2. S. aureus: 10.3% BSI per 10,000 admissions
  3. Enterococcus spp: 4.8% BSI per 10,000 admissions
  4. Candida spp: 4.6% BSI per 10,000 admissions
  5. E. coli: 2.8% BSI per 10,000 admissions
  6. Klebsiella spp: 2.4% BSI per 10,000 admissions
  7. P. aeruginosa: 2.1% BSI per 10,000 admissions
  8. Enterobacter spp: 1.9% BSI per 10,000 admissions
  9. Serratia spp: 0.9% BSI per 10,000 admissions

  10. A. baumannii: 0.6% BSI per 10,000 admissions
• What percentage of all cases of bloodstream infections were polymicrobial?


  13%
• What is a source of catheter-related bloodstream infections (CR-BSI)?


  Microbiology Society
• What are the laboratory results available for diagnosing bloodstream infections?


  • Other laboratory results (biochemistry, haematology) can be available within the first hours of patient admission
  • Microbiological analysis takes longer due to the need for microbial growth
• What is the estimated concentration of circulating organisms during infection?


  1. 10 CFU/mL
• What is the purpose of blood cultures?


  To confirm the presence of microorganisms within the bloodstream
• What are the important considerations for blood culture collection?


  • Taken ASAP; prior to antimicrobial administration
  • Process within 4 hours
  • Taken from veins and not arteries
  • Avoid contamination
• What is the BacT/Alert system used for?


  • Automated continual monitoring system
  • Uses colorimetric technology
  • Measures carbon dioxide levels via indicator strip every 10 minutes
• What happens when microorganisms multiply in the BacT/Alert system?


  CO2 increases, turning the sensor from grey to yellow
• What is the next step after a positive culture bottle?


  Vent bottle and perform Gram stain and initial agar culture
• What can Gram stain results indicate?


  Can indicate the initial nature of the patient's infection
• What are the valves commonly affected by infective endocarditis?

  • Aortic Valve
  • Tricuspid Valve
  • Pulmonary Valve
  • Mitral Valve
• What is infective endocarditis (IE)?


  A microbial infection of the endothelial lining of the heart