PERI-OPERATIVE CARE Flashcards
(87 cards)
1
Q
What is the Hb threshold for administering?
A
70g/L
2
Q
How are blood groups matched?
A
ABO system
Group D of the rhesus system
3
Q
What does RhD+ or RhD- refer to?
A
Presence or absence of Rhesus D surface antigens
4
Q
What proportion of the population is RhD+?
A
85%
5
Q
What will happen if a RhD- patient is given RhD+ blood?
A
They will make an antibody to RhD+ blood (but they don’t attack their own cells)
6
Q
When will rhesus D mismatch cause a problem?
A
In pregnancy as anti-D antibodies can cross the placenta
A woman with RhD- blood becomes pregnant with a RhD+ baby, during childbirth the comes into contact with the foetal blood and develops Rh+ve antibodies
Her second pregnancy is also with a Rh+ve foetus and antibodies cross the placenta and attack the foetal RBCs causing haemolytic disease of the newborn
(In an emergency setting a man can be given RhD+ blood although this is not ideal)
7
Q
What are blood tests before a blood transfusion?
A
Group and save - determines patients blood group (ABO and RhD) and screens for abnormal antibodies (used when blood loss is not anticipated)
Crossmatch - physically mixing the blood to observe for any immune reaction (used when blood loss is anticipated)
8
Q
When should CMV-negative blood products be used?
A
During pregnancy
Intra-uterine transfustions
Neonates
9
Q
Why are irradiated blood products used?
A
Reduce the risk of graft-versus-host-disease
10
Q
Who should recieve irradiated blood products?
A
- Blood from first/second degree family members
- Patients with Hodgkin’s Lymphoma
- Recent haemopoietic stem cell transplanrs
- After Anti-Thymocyte Globulin (ATG) or Alemtuzumab therapy
- Those recieving purine analogues as chemo
- Intra-uterine transfusions
11
Q
When should patients recieve observations during transfusions??
A
- Before transfusion starts
- 15-20 mins after
- At 1 hour
- At completion
12
Q
How should blood products be administered?
A
Green (18G)
Grey (16G) cannula
To prevent cell haemolysis
13
Q
What are the different types of blood products?
A
Packed red cells (red blood cells)
Platelets
Fresh frozen plasma (clotting factors)
14
Q
When are packed red cells given? How quickly?
A
Acute blood loss
Chronic anaemia
Within 4 hours of coming out of the store
15
Q
How much should 1 unit of blood increase a patients Hb by?
A
10g/L
16
Q
Why are more recent G&Ss required (3 days)?
A
As patients given RBCs may produce autoantibodies to donor surface antigens
17
Q
When are patients given platelets? Over how long?
A
Haemorrhagic shock or profound thromobocytopaemia, administered over 30 minutes
18
Q
When should FFP be given?
A
DIC
Any haemorrhage secondary to liver disease
Over 30 mins
19
Q
What is cryoprecipitate? When is it given?
A
Major constituent = Fibrinogen, vWF, factor VIII and fibronectin
Given for DIC with fibrinogen and vWillebrands disease
STAT
20
Q
What are some general complications of blood transfusions?
A
Clotting abnormalities - due to dilution of packed red cells (FFP and platelets should be given for patients recieving more than 4 units)
Electrolyte abnormalities - hypocalcaemia (from the calcium binding agen in the preservative) and hyperkalaemia (due to partial haemolysis)
Hypothermia
21
Q
What are some transfusion-specific complications?
A
ACUTE:
- Acute haemolytic reaction (ABO incompatability - donor red cells are destroyed)
- Transfusion associated circulatory overload
- Transfusion related acute lung injury
- Mild allergic reaction (itching - treated with antihistamine e.g. chlorphrenamine)
22
Q
How to patients with acute haemolytic reaction present?
A
Urticaria
Hypotension
Fever
Haemoglobinuria
Reduced Hb
23
Q
What test confirms an acute haemolytic reaction?
A
Positive direct antiglobulin test
24
Q
How does transfusion associated circulatory overload present?
A
Dyspnoea and features of fluid overload
Obtain a CXR and treat with oxygen and diuretics
25
What are some delayed transfusion complications?
**Infection** e.g. Hep B, Hep C, HIV, syphilis, malaria
**Graft vs host disease** (normally non-irradiated blood) due to a **HLA mismatch** (causes macropapular rash to toxic epidermal necrolysis)
**Iron overload** due to repeated transfusions (e.g. thalassaemia) Organs affected include liver (cirrhosis), pancreas (diabetes), joints (arthralgia), skin (hyperpigmentation)
26
What are the advantages of day case surgery?
- **Shorter** inpatient **stay**
- **Lower infection** rate
**- Cheaper**
27
What is the criteria for day-case surgery?
**Minimal blood loss**
**Short operating time** \<1hr
**No intra-operative or post operative complications**
No specialist aftercare
28
What are the **pre-operative** elements to the **enhanced recovery after surgery**?
- Patient education regarding surgery
- Encourage **weight loss** and smoking/alcohol cessation
- Solids until 6 hours pre-op
- Clear fluids until 2 hours pre-op
- Loading with 12.5% carb beverage within 2 hours of surgery
29
What are the **intra-operative** steps to ERAS?
- Use of **opiod-sparing** analgesia e.g. regial anaesthesia
- Use **minimally invasive surgery**
30
What are the **post op** elements to **ERAS**?
- Adequate **pain control**
- Early **oral intake**
- Multi-displinary post-op patient follow up
31
What proportion of the total body weight is water?
2/3 (2/3 is intracellular fluid and 1/3 is extracellular)
32
How is the fluid in the extracellular space divided?
1/5th is **intravascular** and 4/5th in the **interstitium**
33
What are insensible losses of fluid?
Losses from non-urine sources
34
How can fluid depletion be examined for?
- Dry mucous membranes / reduced skin turgour
- Decreasing urine output
- Orthostatin hypotension
Worsening = increased cap refil, tachycardia, low BP
35
How to examine for fluid overload?
- Raised JVP
- Peripheral oedema
- Pulmonary oedema
36
What are the daily requirements for water, Na+, K+ and glucose?
**Water** = 25 mL/kg/day
**Na+** = 1 mmol/kg/day
**K+** = 1 mmol/kg/day
**Glucose** = 50g/day
37
Where can 3rd space losses be?
Into **bowel lumen** (bowel obstruction) or **into the retroperitoneum** (as in pancreatitis)
38
What are some crystalloids?
**5% Dextrose** (only dextrose and water - used in fluid maintenance - no calorific value)
**Normal saline** 0.9% NaCl used in resuscitation and maintenance regimes
**Hartmann's** - more physiological than normal saline (contains lactate - do not confuse with lactic acid, can't then use lactate - conjugate base - as marker of acidosis)
39
Give an example of a **colloid**?
- **High albumin solution** (used in decompensating liver disease)
40
What are malnourished patients at risk of?
**Reduced wound healing**
Increased **infection rates**
Increased **skin breakdown**
41
What screening tool for malnutrition can be used?
**Malnutrition universal screening tool**
42
How may disease-related cachexia be noted?
- Muscle wasting
- Loose skin
- Clothes not fitting
- Apthous ulcers
- Angular cheilitis
43
What is the preferential order or feeding?
Oral **nutritional supplements**
**Nasogastric tube** feeding
**Gastrostomy** feeding (PEG)
**Jejunal** feeding (jejunostomy)
**Parenteral nutrition**
44
What does a low serum albumin reflect?
Chronic inflammation
Proteinuria
Hepatic dysfunction
45
What are the basic components of enhanced recovery after surgery?
**- Reduction in nil by mouth**
**-** Pre op **carb loading**
**- Minimally invasive surgery**
**- Minimising the use** of drains and nasogastric tubes
**-** Rapid **reintroduction of feeding** post op
**-** Early **mobilisation**
46
Why do entero-cutaneous fistulae not necessitate parenteral nutrition straight away?
Proportion of ECF that heal spontaneously with PN is **relatively small** so strategy should be supporting nutrition prior to a likely surgical repair
47
How are high and low ECF treates respectively?
High (jejunal) = enteral or parenteral nutrition
Low (ileum/colon) = low fibre diet
48
What is the pre-op assessment for?
Identify any **co-morbidities** that may lead to patient **complications**
49
What PMH should be elicited in pre-op assessments?
- **CVD** (HTN and exercise tolerance, risk of cardiac even increases during anaesthesia)
- **Respiratory disease**
- **Renal disease**
- **Endocrine disease**
50
What are some pre-op assessment questions?
- Previous operations?
- Anaestheia before?
- Drug history? Drug **allergies**?
- Malignant hyperpyrexia?
- Smoking / alcohol intake
51
What does ASA grade 5 indicate?
Not espected to servive without operation
52
What pre-op investigations are there?
- **FBC:** anaemia or thrombocytopenia
- **U&Es**: assess baseline renal function for IV fluids
- **LFTs**: assessing synthesising function
- **Clotting screen:** warfarin users, haemophila A/B
- **Group and save**
53
What pre-op imaging is there?
- **ECG** for a baseline
- **CXR**: e.g. for those with resp illness and no CXR in 12 months, smoking history
- **Additional:** Pregnancy testing, Sickle cell test, Urinalysis, MRSA swabs
54
What classification correlates with difficulty of intubation?
**Mallampati classification**
55
When should patients stop eating foot / dairy products?
When should patients stop clear fluids before surgery?
**Food** = 6 hours before
**Clear fluids** = 2 hours before
56
Why do patients fast before surgery?
Reduces risk of **pulmonary aspiration**
57
What prescriptions to stop before surgery and when?
**Clopidogrel** - 7 days prior to surgery due to bleeding risk
**Hypoglycaemics**
**COCP** - 4 weeks due to risk of DVT
**Warfarin** - 5 days
58
What drugs to alter before surgery?
**Subcut** insulin switched to IV variable rate insulin infusion
**Long-term steroids** - musch be continued IV hydrocortisone
59
What drugs to start peri-operatively?
**LMWH** - based on VTE risk assessment (with exception of neck/endocrine surgical patients)
**TED stockings** - below knee ted stockings (exception of PVD, recent skin grafts and severe eczema)
**Antibiotic prophylaxis** - patients havign orthopaedic, vascular or GI surgery have prophylactic antibiotics
60
How are patients with T1DM treated peri-operatively/
First on the morning list
Night before surgery **reduce** subcut insulin dose by **1/3** and **omit morning insulin** and commence an **IV variable rate insulin infusion** pump ('sliding scale' with actrapid)
Prescribe **5% dextrose** and check capillary glucose every 2 hours
Continue until eating then **overlap** their IV variable rate insulin
61
How are patients with T2DM treated?
- If diet controlled then no action required
- If on **metformin** this should be stopped mornign of surgery and other **oral hypoglycaemics** stopped 24 hours before
- Patients then put on IV variable rate insulin along with 5% dextrose
62
When is bowel prep needed? What is given?
**Left hemi-colectomy, sigmoid colectomy** or **abdominal-perineal resection**: Phosphate enema morning of surgery
**Anterior resection**: 2 sachets of picolax the day before
63
What are the 3 types of delerium?
- **Hypoactive** - lethargy and reduced motor activity
- **Hyperactive** - agitation and increased motor activity
- **Mixed** - fluctuations throughout the day
64
What are the risk factors for delerium?
**Age\>65**
**Multiple** co-morbidities
Underlying **dementia**
**Renal impairment**
**Sensory** impairment
65
What are the common causes of delerium?
**Hypoxia** (post-operatively)
**Infection** (UTI or LRTI)
**Drug induced** (benzo, diuretics, opiods) or drug withdrawals
**Constipation** or **urinary retention**
**Electrolyte abnormalities** (hyponatraemia, hypernatraemia, or hypercalcaemia)
66
How to assess a delerious patient?
- Get a **collateral history** from family
- **When** did it start?
- Any **symptoms of an underlying cause**?
- **Co-morbidities** and previous baseline cognition
- **Previous episodes**?
- **Drug history**?
67
What test can be used for delerium?
Abbreviated mental test
Mini-mental state examination
68
What to review in a patient with delerium?
Review observations
Drug chart
Signs of infection (surgical site infection)?
Signs of pain?
Signs of constipation or urinary retention?
69
What are some examples of AMT questions?
Age
Time to nearest hour
Address (for recall at end)
70
What is the **confusion screen** for post-op patients?
**Bloods** - FBC, U&Es, Ca2+, TFTs, glucose, B12, folate
**Blood culture / wound swab**
**Urinalysis** and or **CXR**
**CT head** (if relevant)
71
How to manage delerium?
Identified **cause of delerium treated**: abx/ nasal oxygen/ laxatives
Nursed in **quiet environment** with clocks and regular sleeping pattern promoted
Encourage **oral fluid intake**, provide analgesia
**Haloperidol** is 1st line sedative treatment
72
When does post-op nausea and vomiting usually occur?
Within first **24-48 hours post surgery**
73
What are the consequences for PONV?
Increased anxiety for future surgical proceduces
Increased recovery time and hospital stay
Aspiration pneumonia
Incisional hernias
74
What are some risk factors for post-op nausea and vomiting?
- **Female**
- **Age** (decreases throughout life)
- Previous PONV or **motion sickness**
- **Opiod** analgesics
- **Non-smoker**
- **Intra-abdominal laparoscopic surgery**
- **Middle ear surgery**
- **Gynaecological surgery**
- **Poor pain control** post surgery
75
What areas in the brain control vomiting and nausea? What are the relevant neurotransmitters?
**Vomiting centre** in the medulla (Histamine and 5HT3 receptors)
**Chemoreceptor trigger zone** outside the BBB in 4th ventricle (Dopamine and 5HT3 receptors)
76
What are the neurotransmitters targetted in the GI tract?
**Dopamine**
77
What is the first priority with a patient with PONV?
Ensure they are stable - if not A-E?
78
What to consider with PONV assessment?
Operation likely to cause PONV?
Which anaesthetics?
Which antiemetic?
Consider **infection,** **GI causes** (post-op ileus, bowel obstruction), **metabolic causes** (hypercalcaemia, uraemia, DKA), **medication** (antibiotics, opiods), **CNS causes** (raised ICP), or anxiety.
79
How to manage post-op nausea and vomiting?
- Fluid hydration
- Adequate analgesia
80
What is the anti-emetic of choice?
**Impaired gastric emptying**: prokinetic e.g. metoclopramide (dopamine antagonist) or domperidone (dopamine antagonist) **unless bowel obstruction if suspected**
**Bowel obstruction**: hyoscine (anti-muscarinic) can help to reduce secretions
**Metabolic imbalance** e.g. uraemia, electrolyte imbalance or cytotoxic agents should have **metoclopramide**
**Opiod induced:** ondansetron (5-HT3 receptor antagonist) or cyclixine (H1 histamine receptor antagonist)
81
What are the consequences of poor-post op pain control?
**Slower recovery**: reluctant to mobilise = slower restoration of function
**Not breathing as deeply**: inadequate ventilation and atelectasis = hospital acquired pneumonia
82
What are the steps to the pain ladder?
1st = **simple analgesia** paracetamol / NSAIDs (inhibit synthesis of prostaglandins reducing inflammation)
2nd = **weak opiates** (codeine/tramadol) reassess after 2 hours
3rd = **strong opiates** (morphine / fentanyl) can cause constipation and nausea (possibly sedation, confusion and respiratory distress)
83
What are the side effects of NSAIDs?
**Interactions** (e.g. with warfarin)
**Gastric ulceration** (consider PPI when prescription is long term)
**Renal impairment** (use NSAIDs sparingly here)
**Asthma sensitivity** (triggers asthma in 10% of patients)
**Bleeding risk** (effect on platelet function)
84
How long does morphine take to work:
Orally
IM
IV?
**Orally** = 20 mins
**IM** = 15 mins
**IV** = 2-3 mins
85
When are patient controlled analgesia usually started?
In theatre
86
What is an advantage and disadvantage of PCA?
**Advantage** = analgesia which is tailored to requirements, risk of overdose is negligible and is accutate
**Disadvantage** = prevent patient from mobilising, not for learning difficulties
87
