Diagnostic Investigation and Prediction of Shock
Diagnostic Investigation and Prediction of Shock
Background to the research Patients present to Emergency Departments (ED) with a spectrum of
 illness, many of which are life- threatening. The body has the ability to compensate in the
 early stages when things go wrong so that on the surface patients do not appear as sick as
 they really are. Under-diagnosis of severity of illness leads to under-treatment, unnecessary
 mortality, and unnecessary hospital costs. Earlier diagnosis and consequent treatment will
 result in prudent healthcare, cost-benefit and better patient outcomes.

 Evaluating the true underlying patient haemodynamics such as cardiac output, cardiac power
 and peripheral pressures gives vital clues to the hidden seriousness of illness and is a
 guide to better management. Few EDs in the world assess such haemodynamics. After evaluating
 a haemodynamic protocol one centre in Australia was able to reduce its death rate for septic
 shock at 30 days from 38% to 7%. We would like to evaluate whether the same would occur if
 applied across EDs in Wales. However, before we can do that we need to strengthen our
 understanding of haemodynamics, and of relevant protocols and non-invasive devices that help
 us to acquire such information.

 Study Design After ethics and institutional approval is obtained from we will conduct a
 prospective, single-centre, cohort study on 354 adult patients with possible shock associated
 with an acute illness or injury who present to the Emergency Department of the University
 Hospital of Wales, and follow them up for 7 days. 354 is a credible number to confirm that
 the strategy works.

 Written consent will be obtained either from the patient or a relative wherever possible but
 a waiver of consent apply to patients who, because of confusion, unconsciousness or severe
 disability, may be unable to give consent. In these cases, consent will first be sought from
 a second doctor and/or nurse. Thereafter, consent will be obtained from the patient or a
 relative as soon as practically possible.

 What you hope to discover

 We expect to discover that:

 -  Uscom variables predict 7-day survival and ICU admission

 -  Uscom variables improve the detection and classification of shock

 -  The LiPS definition can be improved.

 -  The objective definition is better than doctors experience

 -  Patients have a good experience and are satisfied with care
Patients frequently present to emergency departments (EDs) with critical illness and injury.
 Shock is a life-threatening emergency, which requires urgent and rapid assessment, diagnosis
 and treatment, and can be classified into distributive-septic (62%), distributive-non-septic
 (4%), hypovolaemic (16%), cardiogenic (16%) and obstructive (2%). Sepsis is the leading cause
 of in-hospital death, and approximately 80% of these patients are admitted through the ED. In
 Chinese patients presenting to an ED in Hong Kong we have previously derived and validated a
 simple, a priori, pragmatic, quantitative method for recognising and classifying shock - Li's
 Practical Shock (LiPS) tool. This method has been validated against ICU admission and early
 mortality. However, it was derived in a single population in a single centre, and requires
 further validation and refined in other settings. Further, it does not sub-classify patients
 beyond 'normal, cold and warm shock', does not guide next steps in treatment, and the
 assessment of the peripheries is very subjective.

 Evaluating the true underlying patient haemodynamics such as cardiac output, cardiac power
 and peripheral pressures gives vital clues to the hidden seriousness of illness and is a
 guide to better management. Few EDs in the world assess such haemodynamics. After evaluating
 a haemodynamic protocol one centre in Australia was able to reduce its death rate for septic
 shock at 30 days from 38% to 7%. We would like to evaluate whether the same would occur if
 applied across EDs in Wales. However, before we can do that we need to strengthen our
 understanding of haemodynamics, and of relevant protocols and non-invasive devices that help
 us to acquire such information.

 There are many unanswered questions such as:

 -  Do Uscom-derived haemodynamic variables measured in the ED predict patients who at high
 risk of death, admission to ICU, and have shock?

 -  Does a refined LiPS definition better predict mortality and ICU admission?

 -  Do advanced haemodynamic predictors and/or refined LiPS predict better than experienced
 physicians the presence and classification of patients with shock, mortality and ICU
 admission?

 This study will answer two main questions:

 1. What is the probability that a patient has shock?

 2. What type of shock does the patient have?

 We propose:

 1. To investigate whether advanced haemodynamic variables using USCOM predict 7-day
 mortality and ICU admission.

 2. To investigate whether advanced haemodynamic variables using USCOM improve the detection
 and classification of shock.

 3. To validate and refine Li's a priori Pragmatic Shock (LiPS) method for detecting and
 classifying shock.

 4. To evaluate clinical experience for shock.

 5. To inform on the feasibility of future studies

 After ethics and institutional approval is obtained from we will conduct a prospective,
 single-centre, cohort study on 354 adult patients with possible shock associated with an
 acute illness or injury who present to the Emergency Department of the University Hospital of
 Wales, and follow them up for 7 days. 354 is a credible number to confirm that the strategy
 works.

 Written consent will be obtained either from the patient or a relative wherever possible but
 a waiver of consent apply to patients who, because of confusion, unconsciousness or severe
 disability, may be unable to give consent. In these cases, consent will first be sought from
 a second doctor and/or nurse. Thereafter, consent will be obtained from the patient or a
 relative as soon as practically possible.

 The challenge is to discover a strategy that has a sensitivity >67% and specificity >72% for
 determining in-hospital mortality in clinically deteriorating or potentially shocked
 patients.
Inclusion Criteria:

 -  Adult patients aged ≥18 years

 -  a NEWS≥3,

 -  requiring a trolley

 Exclusion Criteria:

 • <18 years