Sepsis is the life-threatening organ dysfunction caused by an abnormal and uncontrolled host response to an infection.
It is the leading cause of death in intensive care units, and has an overall mortality of 30-40%. It is a condition that is essential to identify and treat early and aggressively – as any patient admitted with sepsis as a hospital in-patient has an 10% increased risk of mortality.
In this article, we shall look at the clinical features, investigations and management of sepsis.
The criteria for sepsis was updated in 2016. It aims for the early identification of patients developing (or with) a clinical picture of sepsis. There are two criteria required for a diagnosis of sepsis:
- Presence of a known or suspected infection
- Clinical features of organ dysfunction
- Calculating a ‘SOFA score’ (Fig 1) is a means by which clinicians can quantify the level of organ dysfunction.
For a patient with a known or suspected infection, a ≥2 SOFA score indicates sepsis. The SOFA score can also be used to quantify a patient’s clinical course during treatment for sepsis.
Note: The previous sepsis criteria was found to be present in many hospital patients who never actually developed infection or incurred any adverse outcomes. Moreover, 1 in 8 patients admitted to ICU with infection and organ failure did not meet the criteria for sepsis.
The qSOFA score is a shortened version of the full SOFA criteria.
It was developed to allow for the rapid assessment of potential sepsis, based purely on clinical signs. It permits the diagnosis of sepsis to be made prior to any investigations, and can be completed by any healthcare professional.
Any patient with a known or suspected infection and a qSOFA score ≥2 should be investigated and managed for sepsis as necessary. The qSOFA criteria are:
- Respiratory Rate ≥ 22/min (1 point)
- Altered Mental State (1 point)
- Systolic Blood Pressure ≤100mmHg (1 point)
Investigations and Management
In any patient diagnosed with sepsis, immediate investigation and management steps are vital.
These steps are commonly referred to as the ‘sepsis six’ and should be completed within 1 hour of diagnosing sepsis:
|1||100% O2||Start 15L O2 via a non-rebreathable mask, aiming for target saturations 94-98% (COPD 88-92%), and only titrating accordingly once appropriately saturating.|
|2||IV fluid||500 – 1000mL bolus, although more may be required if the patient’s blood pressure does not improve after 15-20mins|
|3||Blood cultures||Take before antibiotics administered. You may also wish to perform other investigations to identify the suspected site of infection|
|4||IV antibiotics||Empirical antibiotics initially (based on local guidelines), before switching to targeted therapy when results are available (given within 1 hour)|
|5||Serum lactate and other bloods||Lactate can be done on either an ABG or VBG. Other bloods should include FBC, U&E, LFTs, Clotting, CRP and Glucose, further assessment of organ dysfunction|
|6||Monitor urine output||Catheterise the patient and accurately monitor urine output. Aim for >0.5mL/kg/hour.|
Ensure that your seniors are involved early in the care of these patients. Ask the nursing staff to take hourly observations, and to inform you if there is any deterioration of the patient.
Further management may include assessment by ICU and commencing vasopressor agents (e.g. vasopressin), renal replacement therapy, and ventilator support.
The definitive treatment of sepsis involves identification of the infection source, as well as the causal agent. Appropriate investigations may include:
- Urine dip/culture
- Swabs (wounds or otherwise)
- Operative site assessment (CT / USS)
- Chest X-ray (CXR)
- Cerebrospinal fluid sample (via LP)
- Stool culture
Whilst many septic patients can be managed in the ward environment with early senior support, involvement of intensive care / clinical outreach teams should be considered when:
- Evidence of septic shock
- Lactate > 4.0mmol
- Failure to improve from initial management
Sepsis on Surgical Wards
The common sources of infection in a surgical patient can be remembered using the Seven C’s:
- Chest (Infection)
- Cut (wound infection)
- Catheter (UTI)
- Collections (Abscesses within abdomen, pelvic or subphrenic)
- Calves (DVT)
- Cannula (Infection)
- Central line (Infection, if applicable)
Septic shock is defined as sepsis with hypotension, despite adequate fluid resuscitation or requiring the use of inotropic agents to maintain a normal systolic blood pressure.
Management usually involves aggressive fluid resuscitation and antibiotic therapy, with the likely involvement of the critical care team. Inotropes are often used to maintain organ perfusion.