Perioperative Care

Question 1

What are the types of surgery (surgery grade)

Answer 1

Grade 1 (minor) – Eg. Excision of skin lesion, draining abscesses

Grade 2 (intermediate) – Eg. Excision of varicose veins, tonsillectomy, arthroscopy

Grade 3 (major) – Eg. Hysterectomy, resection of prostate, thyroidectomy

Grade 4 (major+) – Eg. Total joint replacement, lung operation, colonic resection

Neurosurgery and cardiovascular surgery have their own gradings

Question 2

What are the ASA Grades

Answer 2

ASA 1 – Normal healthy patients, no clinically important comorbidity and insignificant past medical history

ASA 2 – Patients with mild systemic disease

ASA 3 – Patients with severe systemic disease

ASA 4 – Patients with severe systemic disease, threatening to life

Question 3

When should an ECG be done Pre Op

Answer 3

Should always be considered in any patient over 40 years old and should be performed in 80+ year olds – done routinely in patients with hypertension or pre-existing heart disease

Question 4

When should an FBC be done Pre-op

Answer 4

Should always be considered in any patient over 60 years old

Question 5

When should Renal function tests be done pre op

Answer 5

Should always be considered in any patient over 60 years old

Question 6

When should Urine analysis be done Pre op

Answer 6

Should be considered in all patients

Pregnancy testing – in all fertile women
UTI
Undiagnosed diabetes or renal disease

Question 7

Why should you ask about reflux in a Pre-op assessment?

Answer 7

Reflux is an important factor as patients who experience it definitely need intubation, laryngeal mask leaves too high a risk of aspiration

Give medication such as PPI or H2 receptor antagonist in an attempt to prevent reflux and the complications thereof

Question 8

If a patient is found to be thrombocytopaenic pre op, what should be done?

Answer 8

Look for cause of thrombocytopaenia, such as myeloid conditions (leukaemia, myelodysplasia, etc.), infections or spleen issues (splenomegaly)

Patients will need coagulation testing

Question 9

If a patient is found to have Neutrophilia pre op, what should be done?

Answer 9

May be artefactual – read blood film report to be sure, use citrate sample (green bottle) instead if platelet clumping is reported

IV immunoglobulin may improve the platelet count

Question 10

If a patient is found to be thrombocytopaenic pre op, what should be done?

Answer 10

Suggests an ongoing infection – treat it first

Question 11

If a patient is found to be Anaemic pre op, what should be done?

Answer 11

Patients will bleed more during surgery and will have poor wound healing, will need cross match and transfusion in emergency surgery

Try to correct anaemia before surgery if possible, try to find out what could be the cause, erythropoietin injections may be required

Question 12

When to do a Group and save or cross match

Answer 12

For surgeries where blood loss is expected

Group and save if there is a low chance of bleeds

Cross-match if blood-loss is predicted or if patient is found to have atypical antibodies on blood testing, as this will make it harder to source blood at the time with just a G+S on record

Question 13

Why will you ask about allergies Pre-op?

Answer 13

Allergy to egg or soya is important as this often indicates an allergy to propofol will also be present

Patients with an allergy to latex should be done first on the list (so latex spores aren’t floating around), non-latex gloves must be worn

Question 14

Why is it It is important to know the patient’s alcohol history pre-op

Answer 14

If the patient is a heavy drinker then the liver may be damaged, leading to reduced production of clotting factors and a reduced rate of drug metabolism

Question 15

What is Malignant hyperthermia

Answer 15

An Autosomal dominant inherited condition

Fast rise in body temperature due to severe muscle contractions when subjected to general anaesthetics – inhaled agents such as isoflurane/sevoflurane but also suxamethonium

Do not use anaesthetic gases or suxamethonium in these patients if the condition is known prior to surgery

Local anaesthetics work fine so a spinal block or epidural may be the best thing for it

Atracurium or rocuronium instead of suxamethonium (succinylcholine)

Dantrolene should be on hand to reverse this problem
Wrap the patient in a cooling blanket to reduce the temperature

Question 16

What is Suxamethonium apnoea

Answer 16

May be inherited or acquired

Patient is unable to correctly metabolise suxamethonium and therefore it is not removed from the body at the correct rate

Patients will remain paralysed following surgery and must be given fresh frozen plasma, which contains cholinesterase enzymes, to break down the suxamethonium

Use atracurium in these patients instead

Question 17

What risks are higher in a surgery if a patient has asthma?

Answer 17

Patient is more likely to undergo pneumothorax or form bullae during the operation

Risk of bronchospasm

Question 18

What risks are higher in a surgery if a patient has impaired Renal and Liver function?

Answer 18

Patients with reduced eGFR will excrete drugs at a slower rate, meaning they will stay in the system for longer
Patient at risk of overdose or of staying asleep for longer than expected

Caution use of radiocontrast for imaging assisted procedures in patients with low eGFR

Patients with reduced liver function will not metabolise drugs as easily

May not work as quickly
May wear off more slowly
May increase risk of toxic levels

Patients with reduced liver function may also have reduced clotting factors
Liver responsible for factors 1, 2, 5, 7, 8, 9, 10 and 11

Some patients may have a history of waking up sooner than expected in surgery due to hypermetabolism – take this into account

Question 19

What changes should be made pre-op for diabettic patients

Answer 19

HbA1c should be targeted at <60mmol/mol (<7.5%) for surgery – ideal values
<48mmol/mol (<6.5%) is generally the target for diabetics in everyday life

HbA1c must be at least below 69mmol/mol (8.5%) – this is the highest acceptable value

Patients going for elective surgery should have their HbA1c assessed and reduced if necessary in primary care
This will reduce the risk of complications and reduce the time taken to heal

Diabetic patients should have eGFR taken to look for any diabetic nephropathy

Patients missing more than one meal will need to be given a variable rate IV insulin infusion (sliding scale) during the operation
0.45% NaCl and 5% glucose with 0.15-0.3% Kcl (depending on potassium levels)

Target blood glucose for elective surgery is 6-12mmol/L
4-12mmol/L is the acceptable range

Patient should be done first on the list if possible

Question 20

How can you assess an airway for intubation?

Answer 20

LEMON assessment for difficult airways

Look at the external airway, is there anything that may obstruct entry?
e.g. Obesity, micrognathia (small jaw), evidence of previous surgery, trauma or irradiation, facial hair (large beard hard to mask ventilate), dental abnormalities (including large teeth and poor hygiene), high arched palate, thick or short neck

Evaluate 3, 3, 2 rule – 3 fingers should fit in the jaw vertically, 3 fingers from the mentum (front of chin) to the hyoid bone, 2 fingers from the hyoid to the thyroid cartilage notch

Mallampati score – used to predict the ease of endotracheal intubation
Visual assessment of the distance from the tongue base to the roof of the mouth, indicating the amount of available space to work in
An increasing score indicates increasing difficulty of intubation
Cormack-Lehane scale is more accurate and describes what is seen on laryngoscopy during intubation

Obstruction – soft tissue swellings, burns, broken necks, trauma to face or neck, foreign bodies lodged in the airway, excessive soft tissue and obesity

Neck mobility – preferably, neck should be able to be extended during laryngoscopy

Question 21

What Blood thinners and anti-clot agents

will you stop pre-op?

Answer 21

Clopidogrel – antiplatelet agent (inhibit ADP receptors)
Stop 1 week before surgery
May not need to be stopped – depends on patient risk of clot and how soon after a throboembolic event or MI

Aspirin – antiplatelet agent (blocks thromboxane A2 formation)
Stop 1 week before surgery
May not need to be stopped – depends on patient risk of clot
Restart following surgery at surgeon’s discretion

Warfarin – inhibits vitamin K dependent synthesis of clotting factors 2, 7, 9 and 10
Stop 1 week before surgery, cover with dalteparin prophylactic dose (5000 units daily) to prevent thromboembolic events during this week
May not stop if surgery has low bleed risk and risk of thromboembolism is very high

Question 22

What Respiratory medicine will you stop pre-op?

Answer 22

Inhalers should be taken all the way up to the day of surgery, taken on the morning of the day of surgery

Question 23

What Blood pressure medication will you stop pre-op?

Answer 23

Ace inhibitors and ARBs eg. ramipril, lisinopril, losartan, candesartan
Not taken on the day of surgery and continue following procedure

Calcium channel blockers eg. amlodipine, nifedipine, diltiazem
Not taken on the day of surgery and continue following procedure

Beta blockers eg. atenolol, bisoprolol, propranolol
Taken on day of surgery and continued following procedure
Sudden cessation can lead to rebound angina/infarction – may need some during op

Thiazide diuretics
Stop the day before surgery and continue when back on oral fluids

Question 24

What Diabetes medications

medication will you stop pre-op?

Answer 24

Oral hypoglycaemics, eg. Metformin
Omit dose on day of surgery to prevent issues caused by possible changes in renal function
Insulin if necessary while undergoing surgery – Variable rate IV insulin infusion (VRIII)
Insulin until patient can take substances orally again following surgery

Insulin
Omit short acting but continue long acting on day of surgery
Insulin (VRIII) if necessary during surgery and usual dosing following surgery

Question 25

Will you stop Thyroxine pre-op?

Answer 25

Take on morning of surgery and start dose again following surgery

Question 26

Will you stop NSAIDs pre-op?

Answer 26

Short acting (short half life) eg. Ibuprofen and diclofenac – discontinue 2-3 days before surgery

Long acting (long half life) eg. Naproxen and nabumetone – discontinue 1 week before surgery

Question 27

Why is food stopped pre-op, and how long pre-op?

Answer 27

Discontinued to lower the risk of regurgitation and aspiration

Discontinue food 6 hours before surgery
Discontinue water 2 hours before surgery
Breast milk 4 hours, formula milk 4-6 hours

Question 28

Will you stop Oral contraceptive pill pre-op?

Answer 28

Increases risk of DVT by 5x
Stop at least 4 weeks before surgery
Counsel on appropriate alternative contraception
Restart 2 weeks post-surgery

Question 29

Will you stop Hormone replacement therapy pre-op?

Answer 29

Increases risk of DVT by 1.5x
Stop at least 4 weeks prior to surgery
Restart 2 weeks post surgery

Question 30

Will you stop Herbal medicines pre-op?

Answer 30

May affect platelet function, stop them 2 weeks pre-operatively

Question 31

Will you stop Corticosteroids pre-op?

Answer 31

Should not be stopped as this can lead to addisonian crisis

Will probably need to be given IV during some surgeries

Make sure that patient is continued on their steroids following surgery

Question 32

How will you reverse Warfarin in an emergency?

Answer 32

Vitamin K will reduce warfarinisation to drop the INR in 6-12 hours
Obviously not the best solution if the surgery is an emergency

Fresh frozen plasma works better acutely but needs time to thaw and can cause fluid overload in older patients and patients with renal failure

Prothrombin complex concentrates (beriplex/octaplex) – contain clotting factors 2, 7, 9, 10 and vitamin K
Works immediately and is therefore the best solution before emergency surgical intervention

Question 33

What is the treatment for MRSA

Answer 33

Mupirocin 2% nasally TDS for 5 days

Clorhexidine gluconate wash, all over body, for 5 days

Additional pre-operative and intraoperative antibiotics may be given

Question 34

What should all patients be swabbed for prior to surgery

Answer 34

MRSA

Question 35

What are the main induction sedation agents

Answer 35

Propofol IV to induce the initial unconsciousness in a patient

Etomidate or ketamine can be used in cardiovascularly unstable patients (won’t depress cardiac output) e.g. trauma

Sevoflurane can be used as a volatile inducing agent

Question 36

What are the main maintenance sedation agents

Answer 36

Sevoflurane is an inhaled isopropyl ether which can be used for both induction and maintenance of general anaesthesia

Isoflurane and desflurane are other maintenance gases (cheaper than sevo)

Propofol infusion can be used if volatiles must be avoided eg. In malignant hyperthermia

Question 37

What are the main Muscle relaxants

Answer 37

Atracurium, rocuronium or suxamethonium

Not necessarily needed in all procedures, eg. Arthroscopy not normally necessary

Question 38

Why are muscle relaxants used?

Answer 38

Important to stop the patient from moving and to relax abdominal muscles to make incisions easier

Question 39

What are the main Analgesics used pre-operatively

Answer 39

Remifentanil is generally used throughout surgery

Morphine is generally used following the procedure

Inhaled N2O (nitrous oxide, laughing gas) 
acts as an analgesic but is likely to cause nausea and vomiting in patients with risks of post-op N&V

Question 40

What is the most important monitor pre-op

Answer 40

Capnography (CO2) monitoring

Question 41

How can you tell that a muscle relaxant is wearing off if the patient

Answer 41

Can see that muscle relaxant is wearing off if the patient begins to form 2 peaks on capnography – shows that the patient is breathing = diaphragm movement = muscles not relaxed

Question 42

When would you use Bag-valve-mask ventilation?

Answer 42

Used to ventilate patients while equipment is being readied for more invasive ventilation methods

Question 43

What is the Procedure of a Bag-valve-mask ventilation?

Answer 43

The mask is placed over the patient’s face, forming a seal around their mouth and nose so that air cannot escape

Head tilt, chin lift

No head tilt in patients with suspected C-spine injury, just the chin lift (jaw thrust)

Squeeze the air bag regularly, but not too hard or fast, to ventilate the patient – 10-12 breaths per minute is a good rate, roughly 500ml per breath should do in an adult

Can use oropharyngeal airway (guedel airway) to assist with ventilation if necessary – measure a size from pinna of ear/angle of jaw to corner of mouth

Question 44

Problems with bag-valve-mask ventilation

Answer 44

Harder on men with large beards
Harder on patients with high BMI (>26)
Age >55
History of snoring and sleep apnoea – oropharyngeal airway will help with this
Lack of teeth
Contraindicated in the presence of complete airway obstruction – air will all go to stomach
Relatively contraindicated after paralysis/anaesthesia as the risk of aspiration is increased

Question 45

Procedure of a Tracheal intubation

Answer 45

Insert the laryngoscope down the tongue to the vallecula (near the epiglottis) and pull up while tilting the head back

The epiglottis should move with the tongue, allowing visualisation and access to the vocal cords and trachea

Feed the ET tube into the trachea and attach the bag mask, inflate the cuff to stop the tube from slipping out and secure it to the face to stop it from moving about
Can use a bougie to aid intubation if it is hard to feed an ET tube straight in

Ventilating the patient should give a CO2 reading on the capnograph, should make the chest rise and fall and air will be heard entering if auscultated
Pull back a bit if chest rising and falling is one sided – likely that the tube has gone too far and entered the right main bronchus

Question 46

Problems with endotracheal intubation

Answer 46

Patients with a mallampati scores of 4 are hard to intubate as their trachea can’t be visualised, do not try to intubate blind
Use fibre optic laryngoscopy in these patients to visualise more easily

It can be hard to enter the trachea on the first try, while attempting to intubate the patient is not ventilated, if necessary pull out and bag-valve-mask ventilate back to 100% saturation before going at it again

May accidentally enter the stomach, leading to greater likelihood of aspiration and stopping the patient’s ventilation – no reading on capnography indicates you are in the stomach

Question 47

Contraindications of endotracheal intubation

Answer 47

Inability to extend the head/neck as in spinal trauma, spinal degeneration or septic arthritis may be a contraindication
Epiglottal infection
Mandibular fracture
Uncontrolled, oropharyngeal haemorrhage

Question 48

Procedure of a Laryngeal mask airway

Answer 48

Inflate the cuff to make sure it won’t leak, then lubricate and deflate before insertion

Pass down the back of the tongue and advance until the cuff can’t be seen

Inflate the cuff and attach the ventilation system

Question 49

Contraindications of a Laryngeal mask airway

Answer 49

Complete upper airway obstruction

Risk of aspiration in patients with GORD

Question 50

When is Rapid sequence induction/intubation used?

Answer 50

Used in emergencies when patients are unfasted

Question 51

What drugs are commonly used for Rapid sequence induction/intubation

Answer 51

Propofol and succinylcholine (suxamethonium) still commonly used

Question 52

What is the technique for Rapid sequence induction/intubation

Answer 52

Preparation – assessment for which size tube will be needed, IV access achieved

Pre-oxygenation to 100% saturation – gives more time (up to 8 minutes) to be able to work without needing to use rescue ventilation procedures

Pre-treatment as necessary – try to prevent raised intracranial pressure or bronchospasm using atropine and lidocaine

Paralysis – opioids and hypnotics (induction agents) administered, muscle relaxant administered
Sodium thiopentone often used instead of propofol for induction – fast onset

Positioning – get patient in “sniffing” position
Head propped on pillow and tilted back in order to align oral, pharyngeal and laryngeal axes to bring the epiglottis and vocal cords into view

Place the tube – intubate the patient

Post-intubation management – proceed as normal, checking capnograph to make sure the tube is in the right place

Question 53

How do you wake up a patient in an Emergency

Answer 53

Stop giving the patient gases so they begin to wear off

Neostigmine is used to reverse the affects of muscle relaxants

Naloxone can be used to reverse opiates if necessary

Benzodiazepines (used for sedation before surgery) can be reversed with flumazenil

Those at risk of aspiration (patients who would have trouble maintaining their own airway) must be fully awake, and therefore able to maintain their own airway, before taking out assisted ventilation tubes

Once they are awake
Patients will likely need an anti-emetic to stop post-operative nausea and vomiting
Give local anaesthetic to incision areas and analgesia such as morphine should be continued to prevent post-operative pain

Question 54

What are the requirements to be discharged from the recovery room?

Answer 54

Fully conscious, maintain a clear airway and exhibits airway reflexes

Respiration and oxygen rates satisfactory

Cardiovascular system stable, meeting normal pre-op levels of BP, HR and adequate peripheral perfusion

Pain and emesis controlled

Temperature within acceptable limits

Oxygen and IV therapy if appropriate

Question 55

What is a Tracheostomy

Answer 55

A surgical opening in the trachea, made to allow for ventilation in the event of a closed larynx

Question 56

Indications for a Emergency Tracheostomy

Answer 56

Trauma, including facial fractures
Infection
Foreign body
Neurological reasons for reduced ventilation – stroke, head trauma, etc.
Angioedema and other causes of swelling
Can help to wean patient off ventilatory support in intensive care settings
Chronic/elective – when a patient needs longer term ventilation

Question 57

What are the Chronic/elective indications for a Tracheostomy

Answer 57

Laryngeal tumour or tumour compressing the upper airway
Assists clearance of secretions – eg. Bronchiectasis or cystic fibrosis
Less irritating/damaging than having an endotracheal tube in-situ long term

Question 58

Complications of a Tracheostomy

Answer 58

Haemorrhage
Hypoxia if not placed fast enough
Trauma to recurrent laryngeal nerve → vocal cord paralysis
Damage to oesophagus
Pneumothorax
Surgical site infection
Aspiration due to pooling of secretions, bleed or the tube
Airway obstruction from poorly fitted tube
Inflammation → narrowed airway
Tracheal stenosis or fistula

Question 59

What is the Ongoing care

required for a Tracheostomy

Answer 59

Hygiene
The tube requires regular cleaning with replacement of the inner-tube every 5-7 days
The skin around the area needs regular cleaning

Speech
Tracheostomy will prevent speech – speaking valves can be implanted to allow for this

Swallowing
Patient can’t cough to remove secretions → risk of aspiration
Regular suctioning may be beneficial
Trouble swallowing due to increased pressure on oesophagus
Speech and language therapists should be involved

Humidification
Nose and mouth bypassed → no humidification
Keep patients hydrated to keep secretions from being too thick

Question 60

What are the Classifications of wound contamination

Answer 60

Clean surgery
Elective and non-emergency surgery without any traumatic injury
Surgery begins closed, no acute inflammation
No entry to respiratory, GI, biliary or genitourinary tracts

Clean-contaminated
Urgent or emergency case that would otherwise be considered clean
Elective procedures entering the respiratory, GI, biliary or genitourinary tracts; eg. Appendicectomy
No encounter with infected urine or bile

Contaminated
Non-purulent (pussy) inflammation, gross spillage from GI tract on entry, entry into the biliary or genitourinary tract in the presence of infected bile or urine
Penetrating trauma <4 hours old, chronic open wounds to be grafted or covered

Dirty
Purulent inflammation (eg. Abscess)
Preoperative perforation of respiratory, GI, biliary or genitourinary tract
Penetrating trauma >4 hours old

Question 61

How do you Reducing risk of a Surgical site infections

Answer 61

Remove hair around the area using electric clippers

Advise patient to shower before the surgery
Reduced area for bacterial flora to live in

Antibiotic prophylaxis before surgery
No need for prophylactic antibiotics in clean surgery as the risk of infection remains at ~2%
Necessary in any surgery involving insertion of a prosthesis or implant
Necessary in clean-contaminated surgery, contaminated surgery and dirty surgery
Use local antibiotic guidelines – generally broad spectrum

Skin preparation at surgery site with antiseptic (clorhexidine or povidone-iodine)

Scrubbing and maintaining sterile field and sterile equipment use

Cover wounds with appropriate dressing following surgery
Avoid further contact with the wound for 48-72 hours

Question 62

What causes Post-operative chest infection and how do you treat it?

Answer 62

Occur due to lung abnormalities following surgical trauma and anaesthesia – atelectasis

Wound pain leads to shorter, shallower breaths which leads to stasis of air in the lung bases and a greater likelihood of
infection

Coughing reflex is suppressed due to after effects of anaesthesia, meaning bugs are less likely to be coughed out

Treat with chest physio and antibiotics

Question 63

What causes surgical Urinary Tract Infections

Answer 63

Caused by catheter inserted during or following surgical procedures

Question 64

What causes surgical Bacteraemias

Answer 64

Indwelling catheters and cannulas increase risk of bacteraemia and therefore septicaemia

Urinary tract infections can lead to bacteraemia

Anastomotic breakdown and abdominal sepsis

Question 65

What are the bodily requirements for Na, K, and water

Answer 65

Sodium requirement – 1mmol/kg/24hr
Potassium requirement – 1mmol/kg/24hr
Water requirement – 25-30ml/kg/24hr
Slightly different in children:
1st 10kg is 4ml/kg/hr
2nd 10kg is 2ml/kg/hr
The rest is 1ml/kg/hr

Question 66

Causes of low urine output

Answer 66

Pre-renal – dehydration

Renal – CKD or perhaps new AKI

Post-renal – Catheter in-situ may be blocked

Question 67

What ions are lost in Diarrhoea

Answer 67

K+ and HCO3- ions lost

Question 68

What ions are lost in Vomit

Answer 68

K+, H+ and Cl- ions

Question 69

What fluids do you give to a patient in shock?

Answer 69

Do not dilute the blood too much by infusion

Give blood where possible

Do not infuse too fast, as the sharp increase in pressure can dislodge newly formed clots, leading to embolic events such as PE or stroke

Question 70

When should hartmanns solution be used

Answer 70

Hartmann’s should only be used for

resuscitation purposes

Question 71

Causes of fluid losses

Answer 71

Urine
High urine output may point towards diabetes mellitus or insipidus

Faeces
Think about stoma output – a patient with a high output stoma should be treated in order to reduce fluid losses
Give PPIs to reduce the rate of gastric secretion
Give loperamide or opiate analgesia to slow movement of faeces
Instead of water, patients should be drinking WHO solution (isotonic)

Minor losses through perspiration (sweat) and respiration (expiration)

Vomiting – give patient anti-emetics

Bleeds
Patient may be losing blood through an occult bleed or an unseen bleed following surgery

Question 72

Signs and symptoms of dehydration

Answer 72

Dizziness, light headed
Headache
Dry mouth, lips, eyes
Reduced urine output
Low blood pressure

Tachycardia with weak pulse
Lethargy and confusion
Reduced skin turgor
Reduced sweating

Question 73

Can a patient eat with an ileus?

Answer 73

No

Question 74

Can Patients who have had upper GI surgery eat?

Answer 74

Nil by mouth for 1 week following surgery