Risk assessment for non-cardiac surgery

Notes for the Final FRCA, by Kay Davies

Risk Assessment for Non-Cardiac Surgery
Goldman risk factors – 1977
Age>70 5
MI within 6 months 10
Signs of heart failure (raised JVP, third heart sound) 11
Aortic stenosis 3
Rhythm other than sinus 7
More than 5 PVCs in 1 min 7
Poor general medical status: 3
PO2 <8, K+<3, HCO3-<20, Urea >18, creat>270, Deranged LFTs, Bedridden from non-cardiac cause Emergency surgery 4 Intrathoracic, GI, Aortic surgery 3 Risk of Death
Severe CVS complications

Detsky cardiac risk index
modification of Goldman in 1986, correlates better with perioperative morbidity
MI <6 months 10
MI >6 months 5
Canadian Cardiovascular Society angina class 3 10
Canadian Cardiovascular Society angina class 4 20
Unstable angina within 6 months 10
Pulmonary oedema within 1 week 10
Pulmonary oedema at any time 5
Rhythm other than sinus 5
More than 5 PVCs per min 5
Critical aortic stenosis 20
Poor general health 3
Age >70 5
Emergency surgery 4
High risk if more than 15 points
Duke Activity Status Index
1 MET is 3.5ml O2/kg/min
Poor functional activity:
1-4 MET - Light housework Shower/dress without stopping Walk on level ground at 2.5 mph 5-7 MET - Climb flight of stairs without stopping Walk briskly > 4mph on flat Light gardening >7 METS - Digging in garden Carrying upstairs Strenuous sports, cycling uphill, jogging ACTIVITY
Hoovering/ sweeping floor/ carrying groceries
Canadian Cardiovascular Society Classification of Angina
Class 0 - Asymptomatic
Class I - Angina with strenuous exercise
Class II - Angina with moderate exercise
Class III - Angina walking 1 to 2 level blocks or climbing 1 flight of stairs
Class IV - Inability to perform any physical activity without angina

Classification of BP
Optimal <120/80
Normal <130/85
High Normal <139/89 (therefore hypertension is defined as >140/90)
Grade 1 hypertension (mild) >140/90 and <159/99
Grade 2 hypertension (moderate) <179/109 – treat (ie>160/100)
Grade 3 hypertension (severe) >180/110 - treat
Grade 1 isolated systolic hypertension SBP140-159, DBP<90
Grade 2 isolated systolic hypertension SBP>160 , DBP<90 – treat
American College of Cardiology and American Heart Association Guidelines
for Peri-operative Evaluation for non-cardiac surgery –1996, updated 2003
Patient risks:
MAJOR RISK
MODERATE RISK
MINOR RISK
Decompensated cardiac failure Compensated cardiac failure Surgical risks:
HIGH RISK
INTERMEDIATE RISKS
MINOR RISKS
An algorithm is then used to determine what level of investigations the patient needs
pre-operatively.
AAGBI Indications for intubation and ventilation in head injury – 2006
GCS less than or same as 8
Deteriorating GCS by 2 or more points
Seizures
PaO2 <13 on O2
PaCO2 >6
Spontaneous tachypnoea PaCO2 <4
Bilateral fractured mandible
Copious bleeding into the mouth
Loss of protective laryngeal reflexes

Child-Pugh Classification of Liver disease for Assessment of Outcome or all
Types of Surgery

Mortality
Paediatrics
Neonate first 28 days of life or < 44 weeks post conception
Infant 1 months to 1 year
Child > 1 year to adolescence
Low Birth Weight <2500g
Premature <37/40
NCEPOD Classification
1
Within days, suitable for day-time emergency list
Levels of Care
Level 1
Step-down from higher levels
At risk of deteriorating, needing 4 hourly obs
Specialised staff for epidurals, PCA & tracheostomy care
Pre-op optimisation
Extended post-op care
Abnormal physiological parameters
1:2 nurse:patient
(ITU) Monitoring and support of 2 or more organs Co-morbidity of 1 or more organ systems and who need support for an
acute reversible failure of another organ.
1:1 nurse:patient

Levels of Evidence
Level
Description
Single RCT, with narrow confidence interval Systematic review of case control studies Case series/ poor quality cohort/ case control studies/ non-experimental Grades of Recommendations
Grade
Level 4 studies or extrapolated from level 2 or 3 studies Level 5 evidence or inconclusive studies at any level
WHO Criteria Diabetes Mellitus – 1999
Fasting blood glucose >7 mmol/l on 2 days
OGT: blood glucose >11 at 2 hours and at least one other time during the test
OGT: if blood glucose is 7-11 at 2 hours or one value is >11, this is impaired

Diagnosis DKA
PH <7.3
HCO3- <16
Anion gap >16
Ketones in blood or urine
Respiratory Failure
Type I - PaO2<8, PaCO2≤ 6.7
Type II - PaO2<8, PaCO2≥ 6.7
Peri-operative Steroids
Patient on steroids: <10mg/day, no additional cover
>10mg/day and minor surgery, 25 mg hydrocortisone on induction
>10mg/day and moderate surgery, above plus 100 mg/day for
24 hours
>10mg/day and major surgery, above plus 100 mg/day for 72
hours
<3 months, treat as if on steroids
>3 months, no peri-op steroids

POISE Trial
Perioperative ischaemic evaluation study
Multicentre blinded randomised controlled trial of metoprolol vs placebo in 10,000 at
risk patients undergoing noncardiac surgery. It will determine the impact of
perioperative metoprolol on cardiovascular events (cardiovascular death, non-fatal
MI or non-fatal cardiac arrest) in at risk patients during the 30 day post-operative
period.
Collaborative Eclampsia Trial – Lancet 1995
Compared magnesium with diazepam and phenytoin in 1687 women with eclampsia
in developing countries.
52% lower risk of recurrent convulsion using magnesium compared to diazepam.
67% lower risk of recurrent convulsion using magnesium compared to phenytoin,
also the foetal morbidity was lower.
COMET Study – Lancet 2001
Comparative Obstetric Mobile Epidural Trial
1054 woment in nulliparous labour in 2 obstetric units
Women randomised to receive traditional 0.25% bupivacaine top-ups, CSE (1ml
0.25% bupivacaine and 25mcg fentanyl intrathecally with epidural topups 0.1%
bupivacaine with fentanyl) or low dose infusion 0.1.5 bupivacaine and 2 mcg/ml
fentanyl.



Lower rates of instrumental delivery and Caesarian section with the low dose
infusion and CSE groups but not much difference between each of these groups.
50% less bupivacaine used with the CSE group.
Contant 2001
In Traumatic brain injury, CPP randomised to >70mmHg gives a 5 x greater risk of
ARDS, which increases risk of poor outcome.
Therefore the minimum CPP is 60mmHg and CPP>60 mmHg to be avoided.
60mmHg shown to be the critical CPP threshold by Juul 2000 with no extra benefit
using 70mmHg.
CRASH-Lancet 2004
Corticosteroid Randomisation After Significant Head Injury
TBI and GCS< or the same as 14. Randomised to methylprednisolone infusion for
48 hours or placebo. After 10008 patients the trial was stopped as the mortality
within 14 days was significantly higher in the steroid treated group than placebo.
Hypertonic Saline – Critical Care Medicine 2005
A RCT on the effect of 200ml 20% mannitol solution and 100ml 7.5% saline/6%
dextran solution in raised ICP. The hypertonic saline with the dextran caused a
greater decrease in ICP and a significantly longer duration of action.
NASCIS III
IV methyl-prednisolone 30mg/kg over 15 mins followed 45 minutes later by
5.4mg/kg/hr for 23 hours, decreased the severity of long term sequelae if given
within 8 hours of spinal cord injury. This is statistically significant but not clinically
significant.
Low dose dopamine doesn’t prevent ARF in early renal dysfunction
ANZICS Clinical Trials Group – Lancet 2000
Double-blinded RCT. In patients with early renal dysfunction, dopamine does not
reduce the need for RRT, reduce rises in creatinine or the number of patients
reaching a creatinine threshold.
Hypothermia after Cardiac Arrest Study Group- NEJM 2002
Multicentre trial with blinded assessment of outcome. Patients with an out of hospital
VF cardiac arrest, who were resucitated, were randomised to 24 hours of mild
hypothermia 32ºC to 34ºC or to normothermia. 75 of 137 patients in the hypothermia
group had a favourable outcome at 6 months (55%), compared with 54 out of 137
patients in the normothermia group (39%).
In ARI our inclusion criteria for therapeutic hypothermia are:
GCS 3-5
Out-of hospital witnessed collapse with initial rhythm VF in an adult.
5-15 minutes down time (before start of resuscitation)
Not more that 60 minutes to ROSC
Target temperature 33+/- 0.5ºC
Exclusion criteria:
SBP<90mmHg
Other cause of coma
Pregnancy
Coagulopathy
Immediate verus delayed fluid resuscitation for hypotensive patients with
penetrating torso injuries – NEJM 1994
Non-blinded RCT. Patients with on scene initial SBP<90 mmHg.
For every 13 patients in whom fluid resuscitation was delayed, compared to
immediate resuscitation, one extra patient survived.
These victims were young and we cannot assume that the same principal is
applicable to other patients hypotensive in the pre-operative period eg AAA
SAVE Study
Captopril 50mg tds given post-MI with associated poor LV function can reduce
mortality by 40 lives per 1000 patients and results in fewer MI’s or hospitalisation
over a 3.5 year period.
CARE Trial
Pravastatin saved 150 fatal and non-fatal CVS events per 1000 patients treated for 5
years post-MI. with average cholesterol levels.
Late Steroid Rescue in ARDS
Can prevent the proliferative phase and reduce fibrosis.
From 7 to 15 days give 2mg/kg methylprednisolone and reduce the dose over 32
days.
PAFC use does not alter post-operative outcome – NEJM 2003
Single-blinded RCT. ASA III/IV patients over 60 years for elective or urgent
abdominal, thoracic, vascular or hip fracture surgery.
In high risk patients undergoing surgery, PAFC together with GDT did not reducce
mortality. There was a higher use of all interventions in the PAFC group and also a
higher incidence of PE, but no difference in length of hospital stay.
Albumin increases mortality in critically ill patients
Systemic review of RCT BMJ 1998
No evidence that albumin reduces the mortality in critically ill patients with
hypovolaemia, burns or hypoalbuminaemia. Also for every 17 patients given
albumin, compared to crystalloid, one additional patient dies

The SAFE study (a comparison of Saline and Albumin for Fluid resuscitation –
NEJM 2004) was a multicentre double-blinded RCT with 6997 patients with a
heterogeneous group of patients. This went on to show that there was no difference
in 28 day mortality between the two.
PROWESS – 2001
Protein C Worldwide Evaluation in Severe Sepsis
6.5% reduction in 28 day mortality (21%relative risk reduction) ie NNT = 16
ADDRESS – NEJM 2005
Administration of Drotrecogin alfa activated in early severe sepsis
11000 patients
Showed that if there was single organ failure or APACHE <25 then APC caused
increased mortality.
INDICATIONS APC:
2 organ failure of <48 hours duration
APACHE > or the same as 25 or increased risk of death
Evidence of infection and septic shock producing 3 out of
4 SIRS criteria
Receiving full card on ITU and not improving
No contraindications
CONTRAINDICATIONS: Paediatrics (4x increased risk ICH) Within 30 days surgery
Active/internal bleeding
Haemorrhagic stroke within 3 months
Intracranial/spinal surgery/head injury within 2 months
Trauma with increased risk of life threatening bleeding
Epidural
Intracranial neoplasm/mass lesion/evidence of

Other Pain Scores:
Magill Pain Questionnaire
The original questionnaire was long and difficult for many to complete. A short form
containing 15 words was developed. The first 11 words are SENSORY descriptive
words, the next 4 words are AFFECTIVE and the EVALUATIVE component uses a 5
point scale for present pain intensity and a Visual Analogue Scale.
Oswestry Disability Index and Roland Disability Questionnaire
For assessment of back pain
Brief Pain Inventory
This includes:
Pain intensity at worst /best and at the time of evaluation
% pain relief from medication
Duration of pain relief
Exacerbating and relieving factors
Aspects of Pain belief
Level of interference with ADLs

Memorial Pain Assessment Cards
These are 3 separate Visual Analogue Scales for PAIN, PAIN RELIEF and MOOD.
The card is folded so you only see one scale at a time. It is very quick and results
correlate with longer evaluations of pain and mood.
LANNS Pain Scale
Leeds Assessment of Neuropathic Symptoms and Signs. This includes:
5 QUESTIONS:
Ds the pain pricking/tingling/pins and needles? 5
Does it affect the colour of the skin? 5
Is the skin abnormally sensitive? 3
Does the pain occur in bursts/like an electric shock? 2
Is it hot/burning? 1
Cotton wool allodynia 5
Pinprick threshold altered 3
If total > 12 out of 24, this is neuropathic pain (80% specific, 85% sensitive)
Neuropathic Pain Scale – Galer
8 PAIN DESCRIPTIONS: short GLOBAL UNPLEASANTNESS: 0 – 10
hot
cold
skin sensitivity
itching
deep pain
surface pain

Guidelines to look at:
AAGBI Guidelines- blood transfusion, consent, Jehovah’s witnesses, day surgery,
MH, monitoring, safe transfer of patients with brain injury, MRI, perioperative care of
elderly
NICE Guidelines- April 2007 new guidelines for massive PE
NCEPOD Recommendations and recent audits
CEMACH you can download the executive summary and also read the anaesthesia
section
SIGN GUIDELINES: Management of hip fractures, Blood transfusion, Post-operative
assessment
BRITISH HYPERTENSION SOCIETY GUIDELINES
Other Reading:
Your Primary notes or books
Key Topics in Critical Care
Key Topics in Chronic Pain
Key Topics in Anaesthesia
Handbook of Anaesthesia
A-Z of Anaesthesia –Yentis
Clinical Notes for the FRCA –Charles Deakin
CEPD articles – you can get them on disc/ online / printed collated copies

SAQ Tips:
Just print out all the past questions from the FRCA or Royal College website and do
as many as you can as similar topics get repeated. Simon Bricker’s “SAQs in
Anaesthesia” is invaluable.

MCQ Tips:
Loads of practice and answer as many as you can. Many MCQs from “Guide to the
FRCA Examination: the final” (order form the college website) and the FRCA website
came up in the exam, so do them/repeat them a few days before the exam.

VIVA Tips:
Don’t skimp on anatomy. Pester lots of people for practice, especially those who
have done the exam recently. “The Anaesthesia Science Viva” book (Simon Bricker)
is excellent as is “The Clinical Anaesthesia Viva” book (Mills/Maguire/Barker). I also
found “Clinical Data Interpretation in Anaesthesia and Intensive Care” by
Bonner/Dodds interesting to read. More people fail the clinical science viva, so going
through your Primary basic science viva books again may be useful, as well as
giving viva practice to those sitting the Primary.
In the clinical viva, you have 10 minutes to go though a case before the viva. They
will invariably ask you to summarise the case and state what the main problems are,
so prepare this answer. Also think what further information in the history and what
further investigations you would like to get, whether you would anaesthetise the
patient, how you would optimise them for surgery, pre-induction, induction,
maintenance, monitoring, analgesia, extubation and post-operative care.
There are viva courses you can go on too for even more practice.-
Coventry/Liverpool/London/Cambridge.

Source: http://www.nosats.co.uk/Kay's%20Final%20FRCA%20Notes.pdf