Unfortunately, despite advances in modern medicine, no single test can be used to determine if someone has sepsis or not. To confirm a diagnosis, a variety of tests are performed.

SOFA Score

The “Sequential [sepsis-related] Organ Failure Assessment” (SOFA) is a mortality prediction score used in the intensive care unit (ICU) based on blood tests and physiological analyses that are routinely measured in sick patients. These tests measure the function or rate of failure in 6 major organ systems: cardiovascular (heart), central nervous system (brain), coagulation (blood), hepatic (liver), renal (kidneys) and respiratory (lungs). Each category is scored on a scale from 0 (normal) to 4 (highly abnormal). SOFA looks for a change of 2 or more points from the patient’s baseline score to help differentiate an infection from sepsis.


The PaO2/FiO2 ratio measures the amount of oxygen that is breathed in compared to how much oxygen is making it into the bloodstream. If a patient has a low ratio, this means that there is not a lot of oxygen being exchanged in the lungs.  This is a sign that the respiratory system is not functioning properly. Not enough oxygen in the body is a condition known as hypoxia, or too much carbon dioxide in the body causing what is known as acidosis. If the PaO2/Fio2 ratio is low, oxygen therapy may be required. If a patient’s lungs are failing they will often be mechanically ventilated meaning they will have a large plastic tube down their throat and will consequently be sedated.


Platelets are small components of blood that circulate alongside red and white blood cells. Platelets help with the formation of blood clots by clumping together at the site of the wound and plug the wound to stop it from bleeding. A healthy individual has between 150,000 to 450,000 platelets per 1 microliter of blood. Platelet count has an inverse relationship to the severity of the infection. Therefore, the lower the platelet count, the more severe the infection.


Kidneys are responsible for filtering 120-150 quarts of blood per day, removing waste and excess water through the production of urine. Low levels of urine being excreted is an indication that the kidneys are malfunctioning and not filtering out excess water and waste. Creatinine is a waste product released into the blood by your muscles as a result of using energy. Creatinine gets removed from the blood by the kidneys where it can then be excreted in the urine. When there are high levels of creatinine in the blood, it is an indication that the kidneys are not functioning appropriately as they are not filtering the blood properly. When a patient’s kidneys fail they will often be put on a dialysis machine which mechanically filters the blood for them.


Mean arterial pressure (MAP) describes a patient’s average blood pressure over several heart beats. The systolic and diastolic blood pressures are both used for determining the patient’s MAP. A healthy individual will have a MAP of 60 mmHg or higher. MAP is used to determine the rate of blood flow. The better the blood flow, the higher the MAP and therefore the more oxygen and nutrients are flowing to the vital organs. When a patient’s MAP begins to fall, it means that blood circulation is slowing, this could cause many issues. To combat extremely low blood pressure vasopressors are prescribed to help elevate the blood pressure. 

Central Nervous System

The Glasgow Coma Scale (GCS) is a scoring system used to assess the consciousness of a patient. Verbal, eye-opening and motor responses are all rated on the scale. The GCS ranges from 3 (worst) to 15 (best).


Bilirubin is not present in the urine of normal, healthy individuals. It is a waste product that is produced from breaking down read blood cells (RBCs). Old RBCs are naturally broken down every 120 days as a healthy process. The bilirubin circulates through the blood to the liver where it gets processed and eventually excreted. High levels of bilirubin in the body are an indication that your liver is not functioning properly and therefore cannot process and excrete it. Indications of high bilirubin are yellowing of the whites of the eyes and skin otherwise known as jaundice.


qSOFA stands for “quick Sepsis-related Organ Failure Assessment.” It provides a rapid bedside diagnosis using three readily available criteria. For sepsis to be considered, an infection or suspected infection must be accompanied by at least 2 of the following 3 criteria:

  • Breathing rate ≥ 22 breaths/min
  • Low blood pressure (≤ 100 mmHg systolic)
  • A change in mental status

Accompanied by infection, these three criteria indicate an increased risk of a patient developing sepsis and possible death. qSOFA gives clinicians and caretakers an easily measured scoring method by which patients can be prioritized and monitored more closely. The qSOFA scoring helps clinicians to decide whether they need to further investigate the patient for other indicators of sepsis, as well as clearly identifying which patients are most at risk for sepsis or septic shock. The high-risk patients can be put through more extensive screening than patients with strictly a bad infection. The wonderful thing about the qSOFA is that it can be used outside the ICU by any doctor, nurse, or other healthcare provider to ensure more efficient care.


Treatment for sepsis is tailored specifically for each patient. No two cases of sepsis are the same, and therefore each treatment must be carefully designed and monitored to provide the best possible outcome for each patient. The initial site, cause of infection, particular organs affected, and the severity of damage already done can influence how each patient is treated. If you suspect or exhibit early signs of sepsis, it is crucial that you immediately make your way to a hospital for a full diagnosis and treatment. It is ideal to recognize these early symptoms yourself, but if you are unsure visit your family physician or a walk-in clinic doctor for a more confident diagnosis or they may refer you to a hospital. The development of sepsis and septic shock are medical emergencies and must be taken seriously.

Sepsis Six 

Diagnosis of sepsis is often delayed due to the unspecific symptoms presented in sepsis that are also similar to symptoms in other illnesses. Such symptoms include increased heart rate, temperature and breathing rate. Therefore, once admitted to the hospital and sepsis is recognized by doctors, three therapeutic treatments and three diagnostic tests should be performed which are collectively known as the “Sepsis Six”. If completed within the first hour, it can reduce the risk of death by up to 50%. The six steps include:


  • Give intravenous broad-range antibiotics
  • Delivering high-flow oxygen if levels are low 
  • Start intravenous fluid resuscitation

  • Take blood cultures and complete blood count
  • Measure serum lactate 
  • Monitor hourly urine output
Antibiotics are one of the first lines of defense in the prevention and treatment of sepsis. First, a broad-spectrum antibiotic is prescribed that targets a wide variety of common bacteria. Antibiotics are commonly given intravenously (IV) through a vein via a syringe or catheter inserted near the elbow, wrist or back of the hand. The IV method introduces the antibiotics straight into the blood allowing it to circulate through the body quicker and ensure the most efficient method of treatment. Once results from the blood tests are back and reviewed by a doctor, a more accurate antibiotic can be used to target the specific cause of infection more effectively.

Oxygen therapy is used for patients suffering from sepsis. Patients with sepsis and those in particular with septic shock experience difficulties breathing as the original infection spreads to the lungs. When the lung tissue is damaged it can no longer exchange oxygen and carbon dioxide properly. Therefore, resulting in either not enough oxygen in the body a condition known as hypoxia, or too much carbon dioxide in the body causing what is known as acidosis. Getting enough oxygen is vital to maintain consciousness, keep organs from failing and tissue from dying, therefore, it is a necessity for survival. Oxygen therapy provides extra oxygen to the patient either through a mask or nasal tubes. However, if oxygen therapy through a mask or nasal tubes still is not enough, the use of a mechanical ventilation machine may become necessary to support or completely control breathing.

IV fluid resuscitation is used in the treatment of patients with sepsis. During an infection, inflammation causes blood vessels to expand, therefore decreasing the blood pressure and flow. Fluid is given intravenously to replenish the lack of blood components in the circulating blood vessels. Enriched blood provides nutrients and oxygen to various parts of the body and most importantly to the vital organs. Two types of fluids are used for replenishment: colloids and crystalloids.

Vasopressors are a type of medication used to increase blood pressure during septic shock when the patient is not responding to fluid resuscitation. When blood pressure drops dangerously low, the heart is no longer able to circulate blood containing vital nutrients and oxygen to tissues. Vasopressors act on the blood vessels to narrow them and bring the blood pressure back up. Common vasopressors are:

  • Norepinephrine
  • Epinephrine
  • Vasopressin
  • Dopamine

Blood tests are conducted when a physician suspects that a patient may have sepsis. A small sample of blood is taken from the patient before undergoing two types of tests. The first is a blood culture test that is done to detect the presence and type of either bacteria or fungi in the blood that may be responsible for the blood infection. Blood samples used for blood cultures must be taken before the patient starts antibiotic treatment. Second, a complete blood count (CBC) is commonly ordered with the blood culture to determine if there is an increased number of white blood cells. White blood cells are the fighter cells that help to get rid of pathogens, so an increase in them would indicate an infection. Using the results of these tests, the physician can prescribe specific antibiotics to target the identified pathogen.

Serum lactate is measured using a small blood sample and is used to look at whether the cells have enough oxygen to function properly. Lactate is a product of cells in your body turning food into energy. Generally, when there is sufficient oxygen present in the body, the cells can convert food into energy efficiently while only producing minimal amounts of lactate. However, when there is not enough oxygen in the body, the cells must find another way to turn the food into energy that is less efficient and also creates more lactate as a result. The less efficient method produces lactate faster than the liver can break it down. When there is too much lactate in the body, it can potentially cause muscle weakness, vomiting, loss of consciousness or even coma. In sepsis, research has shown that higher levels of lactate in the blood (>2 mmol/L) are associated with an increased mortality risk.

Urine output is monitored in every septic patient, to ensure that the patient’s kidneys are still functioning properly. A small hollow partially flexible tube, also known as a catheter, is inserted into the patient’s bladder to help accurately measure the amount of urine produced. Measuring urine output helps the physician detect signs of kidney failure and circulating blood volume.

Source of Infection, in certain cases, when clearly identified in the form of an abscess or infected wound, necessary treatment steps must be taken. This may include the drainage of excess pus or even surgery to remove infected tissue and repair the damage.

Nutrition during sepsis is very important. A patient’s body uses a lot of energy to fight an infection, but the patient’s energy stores are often depleted once the infection causes tissue damage. This leaves the patient’s cells with less energy to keep fighting the infection. Therefore, it is important that patients with sepsis or septic shock maintain healthy nutritional habits. It is not always easy for the patients to willingly maintain healthy eating habits, especially when patients experience such significant pain and discomfort as well as patients who require mechanical ventilation. It is important for patients to continue to eat after being diagnosed with sepsis or septic shock. Patients that use a ventilator machine will often have a calculated amount of nutrients injected directly into the small intestine through a small feeding tube. This allows for the much needed nutrients to be absorbed right into the bloodstream through the small intestine without further complications.