risk stratification & risk scoring
TRANSCRIPT
Risk stratification & Risk ScoringF I N A L F R C A T E A C H I N G 0 2 / 1 2 / 2 0 2 0
D R V I N E S H M I S T R Y
Outline
• Cardiac risk scoring
• Cardiac Surgery risk scoring
• Respiratory risk scoring
• General risk scoring
• Vascular risk scoring
• Intensive care
Cardiac Risk scoring
• Goldman Cardiac Risk index
• Lee’s (revised) risk Index (RCRI)
Goldman cardiac risk index
• Lee Goldman published this score in 1977;• It was later revised by Lee in 1999;• The Cardiac Risk Index results range from 0 to
53, where the higher the score, the greater the risk for complications:
0-5 Points: Class I 1% Complications6-12 Points: Class II 7% Complications13-25 Points: Class III 14% Complications26-53 Points: Class IV 78% Complications
History:Age > 70 years (+5)Myocardial infarction within 6 months (+10)
Cardiac ExamSigns of CHF: ventricular gallop or JVP (+11)Significant aortic stenosis (+3)
ECGArrhythmia other than sinus or premature atrial contractions (+7)5 or more PVC's per minute (+7)
General Medical ConditionsPO2 <60; PCO2 >50; K <3; HCO3 <20; BUN >50; Creatinine >3; elevated SGOT; chronic liver disease; bedridden (+3)
OperationEmergency (+4)Intraperitoneal, intrathoracic or aortic (+3)
Lee’s RCRI
• High risk surgery; 1
• History of IHD; 1
• History of CCF; 1
• History of cerebrovascular disease; 1
• Diabetes treated with Insulin therapy; 1
• Pre-op serum creatinine > 177 μmols/L; 1
Example 1 – Risk of cardiac event?
• 68 year old male radical nephrectomy for RCC.
• PMH: COPD smoker. Systolic murmur. On haemodialysis. BMI 31. Angina, Pacemaker inserted
Investigations:
• Normochromic normocytic anaemia Hb 90 g/L
• Low platelets
• Raised urea and creatinine urea 17.9, creatinine 586 (potassium normal).
• X-Ray: Cardiomegaly and dual chamber pacemaker, vascath
• ECG: Paced rhythm (atria and ventricles)
• PFTs: Moderate to severe obstruction, Low TLCO(FEV1 55%)
• Echo shows mild MR and LVH
Lee’s Revised score: 4(11% - 1 in 10 chance of serious cardiac complication
Example 2 – Risk of cardiac event?
• 78 male admitted with acute ischaemic lower limb. Radiological management attempted and failed. Listed
for fempop bypass. Also had an episode of chest pain lasting 20 mins, relieved by GTN
• PMH: CABG 20 years ago, PVD, L3-5 spinal decompression but chronic back pain, takes GTN regularly for
chest pain
• Medications: ACE inhibitor, beta-blocker, oral nitrates, diuretic, MST (high dose), aspirin, statin
• BP 135/70, HR60, chest clear, ECG LAD, ?RBBB, no CXR given, weight 75kg, ht 1.75m
Investigations:
• ECG – L axis deviation, LBBB, inferior q waves., slow AF?
• ECHO – moderate LV dysfunction, mild TR, EF 50%, no LVH
• Angio (from 2 years ago) – patent grafted vessels, complete occlusion of original vessels.
• Bloods - Hb 117 (normochromic, normocytic anaemia) U+Es normal, creat was 96 eGFR 64. Clotting normal.
Lee’s Revised score: 2(7% - 1 in 14 chance of serious cardiac complication
Cardiac Surgery Risk scoring
• Parsonnet Score
• Euroscore
Parsonnet Score
• Published in 1989 and still used at
present in some centres.
Parsonnetscore
RiskPredicted
Mortality (%)
0 - 4 Good 1
5 - 9 Fair 5
10 - 14 Poor 9
15 - 19 High 17
20+ Extremely high 30
Euroscore
Euroscore II
Euroscore
• Euroscore I published in 1999; is an additive score; the higher the score the greater
the risk of mortality;
• Euroscore II published in 2003 uses slightly more specific parameters and a linear
regression model. It gives you the mortality risk as a percentage.
Respiratory Risk scoring
• Obstructive Sleep Apnoea:
• STOP-BANG
• Thoracic Surgery:
• Thoracoscore
STOP-BANG
• STOP-BANG questionnaire is a screening tool for obstructive sleep apnoea;
• Does not correlate for any other cardio-respiratory conditions or post-operative
complications;
• Sensitivity of 93% for moderate-severe OSA and 100% for severe OSA;
STOP-BANG Cut-off Sensitivity Specificity PPV NPV
STOP-Bang ≥ 3
87.3 30.7 43.8 79.7
STOP ≥ 2 + Bang ≥ 1
71.6 46.1 45.0 72.4
STOP ≥ 2 + BMI > 35 kg/m2
20.8 85.0 46.1 63.5
STOP ≥ 2 + Neck > 40 cm
33.5 79.0 49.6 65.8
STOP ≥ 2 + male gender
40.1 76.8 51.6 67.5
STOP ≥ 2 + age > 50 y
59.4 56.1 45.5 69.1
• Different combination is used to
increase specificity.
• Overall specificity is only 43% which
results in numerous false positives.
• 33y male, globe rupture after falling on a radiator. He has poorly controlled epilepsy (1-2 seizures per
day) since childhood but says his fall was not as a result of a fit.
• DH- carbamazepine, levetiracetam.
• On examination height 167cm, weight 125kg, BMI 44.9
• Capped upper incisors, MP 3, full beard
Investigations:
• CXR showing: obese, Vagal nerve stimulator
• ABG showing: pH normal range, pO2 8.9, pCO2 6.8, high bicarbonate (>32mmols), HB 170
• Sleep studies showing: AHI 77, 170 desaturations period hour, average says 85%
• PFTs showing normal fev1/fvc, PEFR 55% predicted (although footnote at the bottom mentioned
technique was poor), reduced vital capacity and residual volume
Example 3 - OSA
STOP-BANG score: 5
Thoracoscore
• Thoracoscore was
developed in 2006 and is
currently recommended
by the BTS for patients
undergoing
pneumonectomy.
• However, multiple studies
have shown inconsistent
results, therefore it has not
been widely adopted,
especially in the U.K.
General Risk scoring
• Elective
• SORT - NCEPOD
• ACS – NSQIP
• Emergency
• P-Possum/ NELA-Possum
SORT - NCEPOD
• Surgical Outcome Risk Tool published in 2014.
• Specific for the UK using the information from NCEPOD data for mortality within
30 days of surgery.
• Used 16, 788 patients from NCEPOD
• Validated for use in the U.K.
• Uses 6 variables.
• Obstetrics, neurosurgery, cardiac and transplant surgery not included.
SORT - NCEPOD
ACS NSQIP
• American College of Surgeons – National Surgical Quality Improvement
Programme.
• Based on American data therefore not totally representative of UK population
but reasonably close.
• ACS Risk Calculator - Home Page (facs.org)
ACS NSQIP
ACS NSQIP
P-POSSUM
• Original POSSUM paper published in
1991.
• Physiological and Operative Severity
Score for the enUmeration of Mortality
and morbidity.
• A modification to POSSUM called the
P-POSSUM was published in 1998.
• A systematic review published in 2013
rated P-POSSUM as the most accurate.
[Moonesinghe, 2013]
Vascular Risk scoring
• Elective
• Emergency
• Glasgow Aneurysm Score (GAS)
• Hardman Index
• Vascular Possum score (V-Possum)
Vasc - POSSUM
• Vascular possum uses the same physiological data as P-POSSUM but a different logistic
regression equation is used.
• It is a better fit for predicting mortality in vascular patients than POSSUM or P-POSSUM.
• Extra items considered to be important by the VSSGBI were added to P-POSSUM
however this not add to accuracy of V-POSSUM in predicting mortality.
Example 4 – Mortality risk?
• 78 male admitted with acute ischaemic lower limb. Radiological management attempted and failed. Listed
for fempop bypass. Also had an episode of chest pain lasting 20 mins, relieved by GTN
• PMH: CABG 20 years ago, PVD, L3-5 spinal decompression but chronic back pain, takes GTN regularly for
chest pain
• Medications: ACE inhibitor, beta-blocker, oral nitrates, diuretic, MST (high dose), aspirin, statin
• BP 135/70, HR60, chest clear, ECG LAD, ?RBBB, no CXR given, weight 75kg, ht 1.75m
Investigations:
• ECG – L axis deviation, LBBB, inferior q waves., slow AF?
• ECHO – moderate LV dysfunction, mild TR, EF 50%, no LVH
• Angio (from 2 years ago) – patent grafted vessels, complete occlusion of original vessels.
• Bloods - Hb 117 (normochromic, normocytic anaemia) U+Es normal, creat was 96 eGFR 64. Clotting normal.
Vasc-POSSUM
• V-POSSUM with VSSGBI items; 9.4% Mortality
• V-POSSUM (PS) uses the physiology data only from P-POSSUM
Ruptured AAA
• Hardman index was published in
1996
• 1 point for each
• Score ≥ 2 consistent with a
mortality > 80%
Ruptured AAA
• GAS can be used for both elective
and emergency AAA patients;
Emergency:
• Score = 84 associated with Mortality
of >65%.
• <84 Mortality of 28%.
Elective:
• Mortality of 8.7% score >78.8
• Mortality of 1.4% score <78.8
Myocardial Disease: Angina or prev MICerebrovascular Disease: Prev stroke or TIARenal Disease: Urea >20 or Creatinine > 150
ITU Risk scoring
• APACHE II (Acute Physiology And Chronic Health Evaluation II)
•
• SAPS II (Simplified Acute Physiology Score II)
• SOFAscore
APACHE II
• Acute Physiology And Chronic Health Evaluation II (APACHE) II.
• The APACHE II mortality predictor was originally published in 1985.
• Not used as a predictor in the medical management of patients.
• It use is to compare actual mortality of a critical care units patients population
with the predicted mortality of its population for audit data calculated in the first
24 hours.
• This risk predictor was used in the UK until 2007 and was superseded by
ICNARC’s own risk predictor.
APACHE II
APACHE II
• Most recent variant is APACHE IV
APACHE II Score
Nonoperative Postoperative
0-4 4% 1%
5-9 8% 3%
10-14 15% 7%
15-19 25% 12%
20-24 40% 30%
25-29 55% 35%
30-34 73% 73%
>34 85% 88%
ICNARC
SOFA score for Sepsis
• Initially published in 1996
for the Working Group on
Sepsis-Related Problems of
the European Society of
Intensive Care Medicine.
• Sequential Organ Failure
Assessment (SOFA) score
• Validated across Europe in
1998
• Clinical impact in the U.K.
published in 2009
SOFA score for Sepsis
Mean SOFA Score Mortality
0-1.0 1.2%
1.1-2.0 5.4%
2.1-3.0 20.0%
3.1-4.0 36.1%
4.1-5.0 73.1%
>5.1 84.4%
SOFA ScoreMortality if initial score
Mortality if highest score
0-1 0.0% 0.0%
2-3 6.4% 1.5%
4-5 20.2% 6.7%
6-7 21.5% 18.2%
8-9 33.3% 26.3%
10-11 50.0% 45.8%
12-14 95.2% 80.0%
>14 95.2% 89.7%
SAPSVariable Points
Age, years
<40 0
40-59 7
60-69 12
70-74 15
75-79 16
≥80 18
Heart rate
Worst value in 24 hours; if patient has had both cardiac arrest (11 points) and extreme tachycardia (7 points), assign 11 points
<40 11
40-69 2
70-119 0
120-159 4
≥160 7
Systolic BP, mm Hg
Worst value in 24 hours
<70 13
70-99 5
100-199 0
≥200 2
Temperature ≥39ºC (102.2ºF)
Highest temperature in 24 hours
No 0
Yes 3
GCS
Lowest value in 24 hours; if patient is sedated, use estimated GCS before sedation
14-15 0
11-13 5
9-10 7
6-8 13
<6 26
PaO₂/FiO₂, if on mechanical ventilation or CPAP
Lowest value in 24 hours; if patient was extubated <24 hours ago, use lowest value while on mechanical ventilation
<100 mm Hg/% (13.3 kPa/%)
11
100-199 mm Hg/% (13.3-26.5 kPa/%)
9
≥200 mm Hg/% (26.6 kPa/%)
6
Not on mechanical ventilation or CPAP within the last 24 hours
0
UN, mg/dL (serum urea, mmol/L)
Highest value in 24 hours
BUN <28 or urea <10
0
BUN 28-83 or urea 10-29.6
6
BUN ≥84 or urea ≥30
10
Urine output, mL/day
If patient in ICU <24 hours, calculate for 24 hours (e.g. if 1 L in 8 hours, then mark 3 L in 24 hours)
<500 11
500-999 4
≥1,000 0
Sodium, mEq/L or mmol/L
Worst value in 24 hours
<125 5
125-144 0
≥145 1
Potassium, mEq/L
Worst value in 24 hours
<3.0 3
3.0-4.9 0
≥5.0 3
Bicarbonate, mEq/L
Lowest value in 24 hours
<15 6
15-19 3
≥20 0
SAPS
BilirubinHighest value in 24 hours
<4.0 mg/dL (<68.4 µmol/L)
0
4.0-5.9 mg/dL (68.4-102.5 µmol/L)
4
≥6.0 mg/dL (≥102.6 µmol/L)
9
WBC, x 10³/mm³
Worst value in 24 hours
<1.0 12
1.0-19.9 0
≥20.0 3
Chronic disease
None 0
Metastatic cancer
9
Hematologic malignancy
10
AIDS 17
Type of admission
Scheduled surgical = surgery scheduled ≥24 hours in advanceMedical = no surgery within one week of admissionUnscheduled surgical = surgery scheduled ≤24 hours in advance
Scheduled surgical
0
Medical 6
Unscheduled surgical
8
Interpretation:In-hospital mortality, % = ex / 1+ex
where x = −7.7631 + 0.0737 x (SAPS II Score) + 0.9971 x [ ln(SAPS II Score + 1) ]
QUESTIONS?
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