Random Flashcards
Infection
The invasion of normally sterile tissue by organisms resulting in infectious pathology
Bacteraemia
Presence of viable bacteria in the blood
Sepsis
A life-threatening organ dysfunction caused by a dysregulated host response to infection (Sepsis-3 - 2016), as evidenced by organ dysfunction and infection.
Organ dysfunction = defined as an increase in 2 or more points in SOFA score - predicted mortality of 10% or more. NB SOFA score is an organ dysfunction score - not diagnostic of sepsis nor does it identify those whose organ dysfunction is truly due to infection but rather helps identify pts who potentially have a high risk of dying from infection.
Infection: no clear guidelines to help clinician identify the presence of infection or to causally link an identified organisms with sepsis.
So all sepsis has organ dysfunction by definition; SIRS as a term has fallen out of fashion and is no longer included in the definition of sepsis as it is not always caused by infection.
Septic shock
A subsect of sepsis in which underlying circulatory, cellular and metabolic abnormalities are profound enough to substantially increase mortality (is assoc w hosp mortality >40%).
Defined by patients who fulfill criteria for sepsis as above (have infection and increase in SOFA score of 2 or more) and also, despite adequate fluid resuscitation, require vasopressors to maintain a MAP of 65mmHg or more and have a lactate of over 2.
MODS
Multiple organ dysfunction syndrome = progressive organ dysfunction in an acutely ill pt, such that homeostasis can’t be maintained w/o intervention. Is at severe end of severity of illness spectrum of both infectious (sepsis, septic shock) and noninfectious conditions (eg SIRS from pancreatitis).
Can be classed as primary or secondary.
Primary = the result of a well-defined insult in which organ dysfunction occurs early & can be directly attributable to the insult itself (eg renal failure due to rhabdomyolysis)
Secondary = organ failure that’s not in direct response to the insult itself, but is a consequence of the host’s response (eg ARDS in pts w pancreatitis).
No universally accepted criteria for individual organ dysfunction in MODS, however the organ-specific parameters used in SOFA are commonly used to diagnose MODS.
In general, the greater the number of organ failures, the higher the mortality, w the greatest risk being associated w resp failure requiring mechanical ventilation.
SIRS
SIRS criteria is no longer used to identify those with sepsis since it is present in many hospitalised pts who don’t develop infection (e.g. autoimmune disorders, pancreatitis, vasculitis, thromboembolism, burns or surgery) & their ability to predict death is poor when compared w other scores e.g. SOFA score.
Is considered a clinical syndrome that is a form of dysregulated inflammation. Previously defined as 2 or more abnormalities in temp, HR, respiration or WCC.
qSOFA
Modified version of SOFA score. Identifies patients with suspected infection at risk of poor outcomes typical of sepsis (prolonged LOS, or in-hospital mortality) based on the presence of 2/3 of any of RR>22, SBP<100, altered mentation. Mortality risk of 10% in these patients in general hospital population. I.e. three components, each of which scores 1, and a score of 2 or more is associated with poor outcomes due to sepsis.
SOFA score
Sequential organ failure assessment score. Scores 6 organ systems from 0-4 - resp (PaO2, FiO2), coag (plts), liver (bili), cardio (hypotension, inotrope requirement), CNS (GCS), renal (creatinine). Score of 2 or more suggests presence of organ dysfunction. Dysfunction in 2 or more systems = MODS.
I.e. MODS is quantified by the SOFA score
Intra-abdominal hypertension & ACS
Normal intra-abdo pressure = 5-7mmHg
IAH = sustained or repeated pathological elevation in IAP ≥12mmHg
ACS = organ dysfunction caused by intra-abdominal hypertension (sustained IAP >20mmHg (w or w/o APP <60mmHg) that is assoc w new organ dysfunction/failure)
APP = MAP-IAP (target APP of ≥60mmHg is correlated w survival from IAH and ACS
Classification
IAH: grade 1 (12-15mmHg); grade 2 (16-20mmHg); grade 3 (21-25mmHg); grade 4 (>25mmHg)
ACS: primary or secondary
Classification of oeosphagitis
LA Classification
Grade A - one or more mucosal breaks, confined to mucosal folds, each not >5mm in max length
Grade B - one or more mucosal breaks >5mm in length, but not continuous between mucosal folds
Grade C - mucosal breaks that are continuous between the tops of 2 or more mucosal folds, but which involve <75% of the oesophageal circumference
Grade D - mucosal breaks which involve ≥75% of oesophageal circumference
Classification of gastric ulcers
Historically classified using the Johnson classification, which was anatomically based and related to acidic states:
- type I - lesser curve at incisura; low to normal acid state
- type II - two ulcers; gastric body and duo; high acid state
- type III - pre-pyloric; high acid state
- type IV - high on lesser curve - normal acid state
- type V - anywhere - NSAID related
UGI bleeding scores
- The Rockall scoring system places emphasis on a correlation between M&M and advancing age, shock or significant co-morbidity; score <3 good prognosis, >8 poor prognosis
- derived based on 5 significant risk factors for mortality form a National UK audit
- consists of an initial score from clinical parameters (age, shock, comorbidities) & a complete composite score after endoscopic assessment
- initial score of zero (ie age <60, no tachycardia, no hypotension, no comorbidity): v low mortality
- composite score, incorporating endoscopic info incl cause of bleeding & stigmata of haemorrhage has been validated in prospective studies, but more accurate in predicting mortality than risk of rebleeding
- The Glasgow-Blatchford score (Hb, urea, melaena, SBP, HR, sex, recent syncope, hepatic disease hx, heart failure) predicts likelihood of requiring endoscopic intervention rather than risk of death
- may be able to identify people who don’t need to be admitted to hospital after a UGIB (score of ≤1 are v low risk for rebleeding or mortality)
- advantages over Rockall score, which assesses risk of death, include a lack of subjective variables e.g. severity of systemci diseases, and lack of a need for OGD to complete the score, so can be calculated when first presents
- a simpler version of the score (modified GBS) = calculated using only the BUN, Hb, SBP and HR; score ranges from 0-16
- prospective study of modified score found it performed as well as the full GBS and outperformed Rockall score w regard to predicting need for clinical intervention, rebleeding and morality
How is acid reflux diagnosed and scored objectively
DeMeester score
- acomposite score of the acid exposure during 24 or 48hr ambulatory pH monitoring
- 6 parameters
- percent total time pH <4
- percent upright time pH <4
- percent supine time pH <4
- number of reflux episodes
- number of reflux episodes lasting ≥5mins
- longest reflux episode (minutes)
- composite score >14.72 indicates reflux
Macroscopic appearance of gastric carcinoma - classification
- early gastric cancers: Paris system
- type 0-I = polypoid (protruded or pedunculated)
- type 0-II = nonpolypoid
- type 0-IIa - slightly elevated
- type 0-IIb - flat
- type 0-IIc - flightly depressed
- type 0-III = excavated
- advanced gastric cancers: Borrman classification
- type 1 = protruded
- type 2 = ulcerated w elevated borders
- type 3 = ulcerated w infiltrative margins
- type 4 = diffusely infiltrating
- type 5 = not fitting other types (unclassifiable)
Aberrant biliary anatomy
- aberrant hepatic duct = defined as a duct draining a normal portion of the liver that joins the biliary tree outside of the liver
- normally RHD is divided into a right anterior (medial) and a right posterior (lateral) branch which joins to form a short right bile duct which joins with the left to form a CHD
- variations in 30-40%
- most common variations relate to right posterior sectoral duct which may drain into:
- left hepatic duct - 15%
- directly into CBD - 10%
- trifurcation w right ASD and LHD 11%
- anatomy of left hepatic duct more constant
