PBM: Massive bleeding

 

(Please note there are many embellishments to this summary)

 

List:

·         Crisis management

o   Problems

o   Aims

o   Actions

·         Massive transfusion protocol

o   Triggers

o   Components

o   Damage control resus

·         Numbers

o   Doses and increments

o   Ratios

o   Test aims

o   Hb threshold

o   Platelet threshold

·         ROTEM

o   How it works

o   Parameters

 

Crisis management

 

Problems:

1.       Lethal problem

2.       Not much time

3.       Lots of jobs

 

Aims:

1.       Stop bleeding

2.       Promote clotting

3.       Preserve vital organs

 

Actions:

·         Announce the problem

·         Call massive transfusion protocol

·         Call for extra hands: anaesthetist and nurses

·         Allocate roles: anaesthetic, access, testing, ordering, checking, giving, documenting

·         Lead the team: minimize own involvement in minutiae, keep everyone updated; closed-loop communication

 

Massive transfusion protocols

 

Triggers:

·         Anticipate bleeding +++

·         Thorax, abdo, long bone trauma

·         Obstetric bleeding +++

·         GI bleeding +++

 

MTP components:

·         Recognise: 50% BV in 4h or 100% BV in 24h, >150mL/min

·         Activate: call lab

·         Test: at t=0 and q30-60min

·         Stop bleeding: compression, tourniquets, packing, surgery, angiography

·         Promote clotting: haemostatic resuscitation

·         Give blood: ~4:2:1 and cell salvage. Limit crystalloid

·         Optimise oxygen delivery: Hb + SpO2 + blood flow

·         Deactivate: call lab when bleeding settles

 

Damage control resuscitation principles:

1.       Damage control surgery

a.       Stop bleeding only

2.       Permissive hypotension

a.       mAP 50-65

b.       SBP 80-100

c.       Head injury: SBP 100 if 20-60y, 110 if older or younger

3.       Haemostatic resus

a.       Guidance: traditional +/- viscoelastic

b.       Ratios: 4:2:1 = 1:1:1 (higher -> ARDS, death)

c.       Free blood: cell salvage

 

Numbers

 

Doses and increments:

 

Dose and volume

Increment

RBC

1 bag at a time = 250-300mL

Paeds: ½ x desired ↑Hb x TBW

10g/L

FFP

15mL/kg = 3 bags = 1L

Paeds: 10-20mL/kg

-

Platelets

1 pooled bag = 300mL

Paeds: 10mL/kg

20-40 x 109 / L

Cryo

3-4g = 1 unit

10 bags whole blood cryo

5 bags apheresis cryo

Paeds: 5-10mL/kg

0.5-1g/L

TXA

1g over 10 mins load

1g over 8 hours infusion

-

rF7a

90mcg/kg

-

 

Ratios:

What we call it: 1:1:1

What is in in bags: 4:2:1

4 units RBC = 4 bags = 1L

4 units FFP = 2 bags = 600mL

4 units plt = 1 pooled = 300mL

 

Test aims:

Parameter

Aim

How

Temp

>35

Forced air warmer

Fluid warmer (Level 1, Belmont)

pH

>7.2

Tissue oxygenation

Lactate

<4

Tissue oxygenation

iCa

>1.1

CaCl 10mmol over 10 mins

Hb

Deserves its own table

RBC

Plt

Deserves its own table

Plt

INR

<1.5

FFP

aPTT

<1.5x control

FFP

Fibrinogen

>1.5

Obstetrics ?2 ?2.5 ?3

Cryo

 

Hb threshold:

Population

Threshold

Most people

<70 yes (almost always)

70-100 maybe

<100 no

Acute coronary syndrome

<80 yes

80-100 maybe

>100 no (increases mortality)

Critically ill

<70 yes

70-90 maybe

>90 no

Children

<70 yes

70-90 maybe

>90 no

 

Platelet threshold:

Population

Threshold

Most

<50

Invasive procedures in ICU

<50

TBI

Brain surgery

Eye surgery

Neuraxial surgery

<100

Chemo and stem cell transplant

<10

<20 if risk factors i.e. bleeding, fever

Critically ill

<20

 

ROTEM

 

How it works:

Old method

Blood in cup

Cup rotates around pin

Blood sticks to pin and makes it move

Kaolin: activates clotting

Heparinase: identify non-heparin problem

Functional fibrinogen: antiplatelet to distinguish plt and fibr problems

New method

Measure change in resonant frequency of blood as it clots

The rest is the same

 

Parameters:

Parameter

Definition

Component

R time

Time to 2mm

Coagulation factors

K time

Time to 20mm

Fibrinogen

Alpha angle

Angle to horizontal of line between R and K points

Fibrinogen, platelets

Maximum amplitude

Max amplitude

Platelets

LY30

30 mins after max amplitude

Fibrinolytic enzymes