Pathophysiology of sepsis | Case Study

Thomas, a 70-year-old man, admitted to hospital with a five-day history of coughing with yellow-green sputum, pyrexia, rigors, poor appetite, mild chest pain and increasing difficulty of breathing.

The initial observations are:

Neurological: Altered neurological status, GCS 11/15. Agitated and confused.

Cardiovascular: Sinus tachycardia, HR 135bpm. Hypotension, 90/45 mmHg.

Respiratory: Tachypnoeic, RR 35bpm. Decreased saturation while receiving 6L O2 through Hudson mask.

Metabolic: Febrile, 39 degree

Renal: Oliguric with 20ml/hr urine output. Indwelling catheter (IDC) was inserted.

The blood test revealed that the patient was suffering from hypernatremia, hyperkalaemia, hyperglycaemia, elevated urea, poor creatinine, increased WCC and low platelet count. The ABG indicated that Thomas was experiencing combined respiratory and metabolic acidosis. Thomas was finally diagnosed as sepsis complicated by the right middle lobe streptococcus pneumonia. He required intubation and invasive ventilation support.

In this case study, the pathophysiology of sepsis will be discussed and the mechanism of synchronised intermittent mandatory ventilation (SIMV) volume control ventilation mode will be explained.

Sepsis is defined as the dysregulated inflammatory response caused by severe infection (Neviere 2015). It has the interchangeable definition as Systemic inflammatory response syndrome (SIRS) while the SIRS is resulted by a suspected or confirmed infectious source (Neviere 2015). The concept of SIRS was first introduced by the American College of Chest Physicians (ACCP) and Society of Critical Care Medicine (SCCM) in 1992 (Kaplan 2014). It is characterised by two or more following symptoms. They are fever of high than 38 degree or hypothermia; tachycardia; tachypnoea or partial pressure of arterial carbon dioxide (PaCO2) less than 32 mmHg; deranged white cell count of more than 12,000/µL or less than 4,000/µL (O’brien et al. 2007). Associated with Thomas’s symptoms, it is clear to see that he was definitely experiencing sepsis. It is because that he was febrile up to 39 degree, tachycardic with heart rate of 135 bpm, and had increased respiratory rate of 35bpm as well as the elevated leucocytes count of 14,000 per microliter. The clinical signs are related to the inflammation process which is activated by the body immune system. Due to the severe infection, a large number of proinflammatory mediators are released which in turn result in the serial inflammatory reaction and extensive tissue damage (Neivere 2015). It is reported that SIRS can lead to high mortality rate because of high occurrence of SIRS induced multiple organ dysfunction syndrome (MODS) (Singh et al. 2009). In the following paragraphs, the pathophysiology of sepsis/SIRS will be more comprehensively examined.

The pathophysiology of SIRS is complex. There are a few elements that need to be emphasised. They are acute stress response, inflammatory process and cytokine storm.

Order a Unique Copy of this Paper

Essay Creek is an academic writing service provided to you by, a London-based company.

  • Experience
    Helping students successfully for 11 years.
  • Confidentiality & Security
    Be sure your information will be kept confidential due to our secure service.
  • Quality & Reliability
    8.5 out of 10 average quality score according to our customers' feedback. 97.45% of orders delivered on time.
  • Versatility
    478 active writers in 68 disciplines.
  • 100% money back guarantee
    You can always request a refund if you are not satisfied with the result.

Read more about us

Our team of writers is comprised of people with necessary academic writing skills and experience in various fields of study.

  • Skilled writers only
    We carefully choose writers to employ, paying attention to their skills and abilities.
  • Competence
    Your order will be assigned to a competent writer who specializes in your field of study.
  • In-depth knowledge
    Our writers know both peculiarities of academic writing and paper formatting rules.
  • Motivation
    We keep updated on results our writers show, motivating them to constantly improve their performance.

Read more about our writers

  • Testimonials
    Our clients' testimonials prove we're doing everything right.

Check for yourself

  • Sample essays
    The best way to understand how well our writers do their work is to view sample essays written by them.

View samples

  • Our Free Essay Tools
    Even more opportunities to improve your academic papers.

Bibliography Generator
Words to Pages Converter
Words to Minutes Converter
College GPA Calculator
Thesis statement generator