1. Fluids and Transfusion
Olivia Davies ST6 Anaesthesia, ELCH
Good morning

2. Fluids and transfusion
and why Anaesthesia is a fantastic career….
Today I am going to talk to you about Fluids and transfusion, but more than that I’m here to tell you what a fantastic career anaesthetics is. And it’s not just because during a long case you can do your full week’s shopping on the ocado app.
This potentially tedious topic becomes exciting in anaesthetists hands.

3. As an anaesthetist you are unlikely to be the one laboriously filling out the group and save bottles, or deciding in a leisurely fashion on a 3 hour ward round that you might give some blood or fluid.

4. You are likely to be in a time critical situation where a sound knowledge or what to give and how to give it is essential and may save a life – in theatre, obstetrics or A&E you will need you to act quickly. And what’s more, you’ll be able to see your actions save a life then and there – doesn’t every doctor secretly want that glory?

5. Blood Transfusion So firstly I’m going to talk about blood transfusion
Surgical patients receive a large proportion of blood in the UK and it’s usually the surgeon or anaesthetist making the decision to transfuse. So it’s important that we know what we’re doing.

6. Topics
Why?
When?
Who?
Risks
Massive Haemmorrhage

7. Example 1
A fit patient with a compound fracture of the tibia and a post operative Hb of 7.5 g/dl should be transfused?

8. Example 2
A 70yr old woman with a history of angina and a pre-op Hb of 7.5 g/dl should be transfused?

9. Why? Hb x Sa02 The body at rest uses approx 250ml O2/L blood
Oxygen delivery to tissues (O2 Flux)
= Cardiac Output x Oxygen content of blood
Hb x Sa02
Organs most sensitive to hypoxia are Heart and Brain
The body at rest uses 250ml O2 per litre of blood. That oxygen has to be delivered to the tissues. Oxygen delivery is determined by the cardiac output and the oxygen content of blood. The oxygen content depends upon the Hb concentration and its saturation with oxygen. A reduction in oxygen delivery can therefore occur with a reduction of any of cardiac output, haemoglobin or oxygen saturation. Once O2 delivery drops below a critical level cellular hypoxia results and the 2 most sensitive organs are brain and heart.
And just to say that if you are considering anaesthetics, this equation doesn’t even scratch the surface of the hideous equations you need to know – FRCA is chock full of them. So it’s great if you love this stuff, but if you struggle it doesn’t mean you can’t be an anaesthetist – once you pass the exam you just need to know the principles

10. Why?
The purpose of a red cell transfusion is to improve the oxygen carrying capacity of the blood.
So he answer to ‘why’ is that we’re actually aiming to improve the oxygen carrying capacity of the blood

11. When? Consider the context: Cause and severity of anaemia
Patients ability to compensate for anaemia ( cardiorespiratory disease)
Rate of ongoing blood loss
Likelihood of further blood loss
Balance of risks vs benefits of transfusion
The decision to transfuse needs to be made on an individual patient basis and you need to use clinical judgement. There is no absolute level.

12. It was common practice to transfuse those with an Hb <10
It was common practice to transfuse those with an Hb <10. However the TRICC trial, published in the NEJM in 1999 changed practice. They compared restrictive transfusion practice (transfusing when Hb < 7, to keep hb between 7-10) with a more liberal transfusion practice( transfusing with Hb< 10 to keep Hb between 10-12). They found that a restrictive strategy was superior to a liberal transfusion strategy in critically ill patients, with the exception of patients with significant cardiac disease.

13. Transfusion Triggers Hb >10 NO Hb < 7 YES Hb 7-10 MAYBE
Cardiopulmonary reserve needs to be assessed.
Symptomatic patients should be transfused. (fatigue, dizziness, shortness of breath, new or worsening angina)

14. Risks
So if you are undecided, why not just transfuse a couple of units of blood? Well there are risks, and blood is a precious resource relying on human donors for its supply.
Patients are still fairly regularly given the wrong blood with potenitally catastrophic results. There are concerns over bacterial and viral transmission, immunomodulatory effects. (Acute immune haemolytic reaction, TRALI, GvHD)

15. Example 1
A fit patient with a compound fracture of the tibia and a post operative Hb of 7.5 g/dl should be transfused? T F

16. Example 1
A fit patient with a compound fracture of the tibia and a post operative Hb of 7.5 g/dl should be transfused? T
F ✔

17. Example 2
A 70yr old woman with a history of angina and a pre-op Hb of 7.5 g/dl should be transfused? T F

18. Example 2
A 70yr old woman with a history of angina and a pre-op Hb of 7.5 g/dl should be transfused?
T ✔ F
This is an elderly patient with a history of cardiac disease so she fits the criteria as we know the heart is one of the most sensitive organs to hypoxia and his coronary supply is already compromised.

19. Summary Think before you transfuse!
Does your patient really need blood?
Weigh up the benefits vs risks of transfusion.

20. Massive Transfusion

21. Massive Transfusion Obstetric Trauma Surgical Medical Settings
In my anaesthetic career by far the most common place I have experienced this is obstetrics. I’m afraid that however you feel about obstetrics, you WILL have to do it for more time that you feel is strictly necessary. So you might as well really hone your transfusion and fluid skills. Other places I have come across this are variceal bleeders and trauma in A&E.

22. Massive Transfusion Definitions
Replacement of one blood volume in a 24 hour period
Transfusion of >10 units in 24 hours
Transfusion of 4 or more units within 1 hour when ongoing need is foreseeable
Replacement of >50% of the total blood volume within 3 hours
Obstetrics
>2000mls
>150mls/min
Uncontrolled/ ongoing
Definitions
There are various definitions of massive transfusion which makes standardising protocols and research difficult. These include:
Replacement of one blood mass in a 24 hour period
Transfusion of >10 units RCC in 24 hours
More dynamic definitions which are possibly more relevant in an acute setting include
Transfusion of 4 or more RCC within 1 hour when ongoing need is foreseeable
Replacement of >50% of the total blood volume within 3 hours
In obstetrics there are yet more definitions.

23. You may hear phrases such as CODE RED – major haemorrhage and CODE BLUE – major obstretric haemorrahage.
What is important to you as an anaesthetist? I think you will find in these situations that the biggest challenge is communication. Remember unless the patient is vomiting out of their varices you may NOT be able to see the bleeding so you need to keep an open dialogue with the surgeon, much as you may want to avoid that. By the time the BP/ HR change they are already shocked. You need to recognise the problem early. Put out the code call. Don’t get focused on fiddling with putting an art line in until the call is out and everyone knows there is a problem.

24. Get some Help…. CODE RED/ CODE BLUE Senior anaesthetist/ surgeon/
obstetrician
Blood Bank
Haematologist
Porter
Get someone to coordinate to communicate and document
Once the code call is out an number of people are notified… Massive haemorrhage situations can develop very quickly and its important to have extra hands around – checking blood units etc – and it really helps to delegate a scribe.

25. CODE RED Code Red Pack A: Code Red Pack B: 6 units RBC 4 units FFP
1 pool platelets
2 pools cryoprecipitate

26. The Massively Bleeding Patient…
Restore Circulating Volume:
X 2 14G IV cannulae
Resuscitate with warmed crystalloid/colloid
Warm patient
Consider invasive monitoring: arterial line + central venous access

27. Arrest the Bleeding….
It’s no good you pouring in blood and blood products if there is a surgical cause of bleeding. The surgeons or obstetricians need to stop the bleeding. Sometimes the interventional radiologists will also intervene (that is your worst nighmare – anaesthesia in an unstable patient in the bowels of the hospital which is IR).

28. Request Lab investigations
FBC, ABG
Coagulation screen
X- match
Repeat after products/4hourly
May need to give blood products before results are available
As you get access, pull off some bloods including… You will need to let the lab and the porters know that they are time critical.
In some hospitals you may have near patient testing like TEG which is extremely useful in these situations but not everywhere does. Lab turnaround times can be very long in some hospitals so you may need to give blood products before you’ve got the results back

29. The Perfect Clot! Red blood Cells Platelets Clotting factors
Fibrinogen
Unfortunately its not just as simple as just giving blood, we also need to give platelets, clotting factors and fibrinogen.

30. “Bloody Vicious Cycle”
This is the cycle where the initial resuscitation results in haemodilution hypothermia and acidosis which in turn leads to coagulopathy and further bleeding .
The combination of hypothermia, acidosis and coagulopathy is referred to as the Triad of Death- once you get into this triad, resuscitation is much more difficult and mortality rises steeply.

31. Effect of Hypothermia on coagulation factor activity
Avoid allowing the patient to get too cold. Hypothermia might occur because of out of hospital trauma, exposure during surgery, immobilisation and administration of unwarmed fluids. It has a profound effect on platelet function, which stop functioning effectively below a core temp of 32
Coagulation factor activity also falls about 10% for each degree c

32. Request PRC Uncrossmatched Group O Rh neg
Uncrossmatched ABO group specific
Fully X match
Use a blood warmer/ rapid infusion device
Consider cell salvage
Back to requesting blood or packed red cells.. Request ‘flying squad’ or Group O neg only in extreme emergencies, you should be able to access it in seconds from the local fridge. You can generally get group specific within about 30mins, and fully x match will take about 45mins to 1 hr. Do this if time permits or there are irregular antibodies.

33. Request Platelets On site?
Anticipate plt count<50 x109/l after x2 blood vol replacement
Target plt count>100 x109/l for multiple/CNS trauma, > 50 in other situations
Many hospitals get there platelets from an external site so you need to order early.
Anticipate plt count<50 x109/l after x2 blood vol replacement
Target plt count>100 x109/l for multiple/CNS trauma, > 50 in other situations.
While were on the subject of platelets in other situations : stable patient in the absence of bleeding a count of >10 doesn’t warrant transfusion, but if you’re thinking of doing any kind of invasive procedure you’d want the count> 50.
Each dose of platelets should raise your count by about 20.

34. Request FFP Aim for PT/ APTT < 1.5 x control Allow for thawing time
Each bag of FFP is about 200ml- 250ml. Contains all the clotting factors including some fibrinogen.
In an acute blood loss situation the recommended dose is 15ml/Kg.
More recently, particularly in trauma from combat situations and HEMS, recommendation for massive haemorhage is to give FFP and blood in a 1:1 ratio. I think you’ll have trouble persuading your local DGH haematologist to provide this..

35. Request Cryopreciptate
Contains fibrinogen and factor VIII
Aim for fibrinogen >1g/L

36. Summary Recognise! Communicate! Code call! Get help!
Beware hypothermia/acidosis/ haemodilution and coagulopathy

37. IV Fluids
Other IV Fluids

38. Normal Adult Fluid Composition
60% composed of water 70 kg person= 42 L 2/3 ICF = 28L 1/3 ECF = 14L Total Body Water = ECF + ICF
ECF = Plasma 3 L + IF L

39. Daily Requirements 4 ml/kg/h for the first 10 kg
Paediatrics:
4 ml/kg/h for the first 10 kg
2 ml/kg/h for the next 10 kg
1 ml/kg/h for every kg over 20 kg
Adult:
25-30ml/kg/day
1 mmol/kg/day Na, K+, Cl-
g/day glucose (5% glucose contains 5 g/100ml)
You need to start with the basics – how much fluid do we need? This is the paediatric formula, and these are the NICE recommendations for adults

40. NICE guidelines – algorithms for iv fluid therapy in adults

41. NICE: iv fluid therapy in adults
Algorithm 1: Assessment
ABCDE
Algorithm 2: Resuscitation
500ml crystolloid bolus over 15 mins up to 2L
Call for help
Think about this when you go to assess a patient on the ward or in A&E.
1:ABCDE: assess volume status

42. NICE: iv fluid therapy in adults
Algorithm 1: further assessment
History
Clinical examination
Clinical monitoring
Lab
Can the patient meet needs orally/ enterally?
Complex replacement or distribution issues?
Following fluid resuscitation, or if your patient does not need resuscitation, return to your assessment:
History – previous intake, thirst, vomiting
Exam – HR, BP, cap refill, JVP, oedema, postural hypotension
Monitoring – fluid balance chart, weight
Lab – FBC, U&E

43. NICE: iv fluid therapy in adults
Algorithm 3: Routine maintenance
Algorithm 4: Replacement and Redistribution
Fluid/ electrolyte deficits or excesses?
Abnormal fluid/ electrolyte losses?
If the pateint has no complex fluid or electrolyte issues go to algorithm 3: routine maintenance which we have talked about
4: Check for fluid or electrolyte deficits or excesses – so look for dehydration, fluid overload, K abnormality
Losses – NG, vomit, diarrhoea, stoma, biliary drainage, blood loss, sweating, pancreatic fistula, urinary loss eg AKI pollyuria

44. Pre-operative protocols
Starvation Protocol:
Starved for 6 hours
Can take clear fluids up to 2 hrs before surgery
Carbohydrate rich drink up to 2 hrs before

45. Intraoperative third space losses
Surgical Trauma
Third space loss ml/kg/hr
Superficial
1-2
Minimal
3-4
Moderate
5-6
Severe
8-10
Minimal Surgical Trauma- head and neck, hernia, knee surgery
Moderate Surgical Trauma- hysterectomy, chest surgery
Severe surgical trauma: - AAA repair, nehprectomy

46. Intra-operatively Cardiac Output monitoring
Goal directed fluid therapy
Lidco, oesophageal doppler
GDFT:

47. GDFT Lidco rapide
Record SV. Give 250ml crystalloid or colloid via large cannula – use 50ml syringe via 3 way tap. Record change in SV. If increase of >10% repeat fluid bolus. Check every 15 mins.

48. Post- operatively Stop iv fluids when no longer needed
NG fluids or enteral feeding is preferable if >3 days.
HDU/ ICU

49. Elective, well patient
Q: Fit , young 60kg pt having elective superficial surgery, what fluid losses do you expect before and during surgery of less than an hour?

50. Do you need to give fluid?
Starved 6 hrs
Deficit: 30ml/kg/day, 6 hrs = 450ml
Intra op losses 1 ml/kg/hr = 60ml
510ml total
Probably doesn’t need fluid
Feel better? Less PONV?
Put up a bag! Much easier to flush through drugs and check your drip is working.

51. Emergency Laparotomy Pt
Q: Patient needing urgent laparotomy, history of vomiting for several days. Do they need fluid?
Yes lots!
Resuscitate
Water and electrolytes
H+, Cl- loss
K+ replacement
Check serum electrolytes before and after fluid resuscitation
Consider starvation, vomit, diarr, ng losses, sweat, high resp rate.
Electrolyte imbalance

52. What? Crystalloids Colloids
A Little bit controversial There is little to favour one over the other

53. Colloids Contain large molecules suspended in a carrier solution
Large molecules stay in the plasma, keeping infused fluid largely in circulation.
Smaller volumes needed
Small risk of anaphylaxis
No starches in UK now
Restoring the circulating volume with these fluids is rapid and sustained.

54. Crystalloids Contain water and dissolved electrolytes
Pass freely through a semipermeable membrane
Need larger volumes
Cheap
So they don’t stay in the intravascular compartment
No allergic reaction

55. Crystalloids 131 111 5 29 2 154 Na+ Cl- K+ Lactate Ca Mg Other
Hartmann’s
Solution (CSL)
131
111 5 29 2
0.9% Saline
154
5% glucose
Glucose 50g/l
Here are some common ones: Their make up varies – Hartmanns is considered a ‘balanced’ solution. 5% glucose is effectively giving free water as the glucose is wholly metabolised+ the resulting water will redistribute into all the compartments going mainly intracellularly. This is important as giving free water can lead to cerebral oedema.

56. Summary Think about why you are giving fluids
Work out how much fluid to give
Select what type of fluid to give
Monitor
Why: maintenance, resuscitate?
How much: what is the deficit are there ongoing losses
Which: consider electrolyte disturbance, crystalloid/ colloid
How will you measure? – CO monitor, fluid balance chart

57. Thank you