Acute medical problems in GI practice

KrishnadasMMM-IGLD

Overview

• Hypovolumic shock

• Early goal directed therapy in septic shock

• The bleeding coagulopathic patient & blood product use

• Stress ulcer prophylaxis in the ICU

Hypovolumic shock

Hypovolumic shock resuscitation

• Shock reversible initially (vascoconstrictive) but rapidly becomes irreversible (vasodilatation)

• Early rapid correction of Hypovolumic shock prevents the development of irreversible shock

• Treat it like door to fluid time!!

Hypovolumic shock resuscitation

• Always consider 1-2L of isotonic saline STAT to restore tissue perfusion

• The above may not be appropriate in the cirrhotic pt

Which fluid?

• Blood/PRCs are the fluids of choice in the bleeder

• Try not to raise hematocrit more than 30-35%

• Choices available: Colloids including hyperoncotic starch, RL, NS, DNS. 5%D etc

Colloid vs Crystalloid

• Colloids not better than crystalloids & also costly

• Large volumes of crystalloids may be required( x 3 times) due to interstitial distribution

• Saline also corrects interstitial fluid deficit

• Hyperoncotic starch solutions increase AKI, Coagulopathy & mortality!!

• ? RL better than NS as it is buffered solution

How to give fluids rapidly?

• How good is our humble venflon?

• Is central line necessary for rapid fluids ?

• Answers: wide bore venflon has excellent flow rates; Central line is not always necessary for volume resuscitation alone

• Mandatory to insert 2 X 16 G venflons in shock

Venflon flow rates

• 20g :40ml/minute

• 18g :75ml/minute

• 16g :150ml/minute

• 14g :300ml/minute

• For equal diameters, peripheral cannulas of shorter lengths can achieve almost twice the flow rates!

• 16G CVC of 16cm length has flow rate of 50mL/minute only!!

Central venous catheterization

• Mandatory when shock not reversed with early resus or when 2 X 16G cannula access is not feasible

• CVC is mandatory in the co-morbid patient for better hemodynamic assessment

• Which CV vessel access is safer?

Central venous catheterization

• Which is easiest?

• Would you put it in a patient with coagulopathy?

• Is femoral any good for CVP monitoring?

Central venous catheterization

• USG guided versus landmark technique.

• Pronovost checklist adherence proven to reduce infection related mortality: CDC recommendation

• Hand washing

• Full barrier precautions during insertion of CVCs

• Chlorhexidine for skin disinfection

• Avoidance of the femoral insertion site

• Removal of catheters when no longer indicated

Pulmonary artery catheterisation

• Useful when CVP is unreliable i.e DCM, pulmonary HTN etc

• No mortality benefit shown; falling out of favor

• Still widely used though.

Vasoactive agents

• Always “fill up” the hypovolumic patient adequately before vasoactive agents are started

• Nor epinephrine : agent of choice in warm sepsis- DB-RCT of 32 pts ( NE vs Dopamine, 93 vs 31 % MAP response)

• Cold sepsis: NE better than dopamine

• SOAP study-Observational study which suggested inferior outcome in dopaminised ICU patients-? dysrhythmias

Buffer therapy in shock

• Bicarbonate therapy is controversial in hypo perfusion lactic acidosis

• Current recommendation-Treat underlying pathology i.e. Shock; Use bicarb to keep pH>7.15 only

Septic shock & EGDT

• Septic shock = SIRS + SBP< 90 after fluid challenge at 30min/lactate>4mmol/L

• SIRS: Temp>38 or<36--- HR >90---RR>20 or paCO2<32—WBC>12K or<4K or>10% immature bands ( 2 of these 4 is SIRS)

Septic shock & EGDT

• EGDT is a globally accepted intense hemodynamic monitoring based resuscitation protocol for septic shock published by Dr.E.Rivers in NEJM 2001

• The protocol starts in ED not ICU!!

• EGDT is a part of sepsis bundle including broad spectrum Abx, glycemiccontrol, steroid etc

Typical EGDT protocol

Management of bleeding in a patient with coagulopathy

Use of Vitamin K

• Vit K- PO safest; IV only for rapid correction

• Use lowest possible vit K dose (5-25mg)

• Vit k iv to be given over 30 min

• Vit k can take 6- 24 hours to correct INR!

Fresh Frozen Plasma

• FFP dose-10-15ml/kg

• Formula exists for exact dose calculation of FFP to achieve target INR

• Amount of FFP needed (ml) =

(target level as % - present level as %) x Wt.(kg)

FFP dose calculation

• % of prothrombin complex at various INR ranges:

• INR 1 = 100 (%)

• INR 1.4 - 1.6 = 40

• INR 1.7 - 1.8 = 30

• INR 1.9 - 2.1 = 25

• INR 2.2 - 2.5 = 20

• INR 2.6 - 3.2 = 15

• INR 4.0 - 4.9 = 10

• INR > 5 = 5 (%)

FFP dose calculation

• Please calculate the FFP dose required to correct INR of a pt (70Kg) to 1.4;He is bleeding & INR is 7.5.

• FFP in mL=(40-5)X70= 2450mL

• This was published in NEJM August 2003

• FFP helps but volume may be problem in the DCLD patient

Platelet transfusion

• Transfuse in a bleeding pt below 0.5 X1011/L, non bleeding febrile pt < 0.2 X1011/L, non bleeding afebrile pt < 0.1 X1011/L.

• UK blood services: 1 Adult therapeutic dose- 75% of it should contain at least 2 .4 X 1011 PLTs

• Choose single donor apheresis platelet than pooled to reduce alloimmunisation/ multi donor exposure

• Check for PLT refractoriness: counts @ 1&24hours post

Platelet transfusion

• 1 U Whole blood PLT concentrate may contain 0.55 to 0.8 x 1011 only

• 1 U apheresis PLTs has 3 to 6 x 1011

• 1 ATD increases count by 0.3 X1011 /L in 10-60 min post-transfusion

• Splenic sequesters with thrombocytopenia-optimal target not agreed upon; ? Treat when bleeding alone/ prophylaxis for high risk procedures

Prothrombin complex concentrates

• They are Vit K dependant factors-2,7,9 &10

• Currently licensed for use in warfarin associated severe bleeding only

• But has been successfully used to reduce INR in bleeding CLD pts including variceal

• Dose 50U/kg

• ? Available in Chennai

Recombinant activated Factor VII

• rVIIa works by causing thrombin burst & can cause powerful coagulation

• Coagulopathy is corrected instantly & lasts for 2 hours

• rVIIa (novoseven) may help in life threatening bleed when all else has failed/Useful in volume intolerant patients

• Novoseven is available in Chennai

Recombinant activated Factor VII

• In Cirrhosis it may supplement FFP , to reduce volume required to correct INR

• FDA approved indication in acute liver failure pts requiring invasive procedures

• Dose 5-120 mcg/kg; average dose used 40mcg/kg

Prevention of GI bleed in the ICU

STRESS ULCER PROPHYLAXIS

The American Society of Health System Pharmacists-Major Risk Factors

• Mechanical Ventilation for 48 hours or more

• Coagulopathy-PLT<50K, INR>1.5, PTT 2 X control

• GI Bleed in the last year

• Traumatic brain/spinal injury

• Burns>35% of BSA

Minor Risk Factors

• Sepsis

• ICU admission > 1 week

• Occult GI bleed> 6 days duration

• Glucocorticoid therapy-250mg of hydrocortisone or equivalent

• Need 2 or more of the above

Why SUP is important?

• Overt GI bleed with Stress Ulceration increases mortality

• A prospective cohort study showed that mortality was higher among ICU patients with clinically important GI bleeding than among those without bleeding (49 vs 9 %)

Which agent to use?

• PPI only slightly better than H2RA -difference very small.

• Level A evidence is for H2RA/sucralfate only

• PPI/H2B better than sucralfate / antacids.

• Early Enteral nutrition appears effective SUP but drug therapy still recommended

Which agent to use?

• Continuous infusion of H2RA better than bolus

• H2RA/PPI associated with nosocomial pneumonia than sucralfate-more research needed

• Choose patient/drug in a case-by-case basis

Any questions?

Thank you & have a great day!