Intensive Care MedicineTopics for the Final FRCA :Intensive Care MedicineTopics for the Final FRCA Dr. Andrew Ferguson
Why ICU matters for the FRCA… :Why ICU matters for the FRCA… 20 specific questions in MCQ
Helps with medicine/surgery MCQs
SAQs - 1 or 2 questions for sure…maybe more
SOE 1 - potential topic/part of topic
SOE 2 - 10 minutes of pure fun!
Be calm… :Be calm… The examiners are human (honestly!!!)
The questions are (mostly) mainstream
You will have seen many of the cases
Guillain-Barre / Myasthenic crisis / weakness
Brainstem death
Status epilepticus and asthmaticus
Trauma
Septic shock
ARDS
Acute pancreatitis
Burns
Some questions just won’t lie down and die e.g. PAC
But don’t be complacent… :But don’t be complacent… People still fail the exam! 10/17 passed in 2008
Don’t assume you know enough…make sure you do
Structure…structure…structure!
Don’t waffle - answer the actual question, not the one you wanted to be asked!!
Other potentials… :Other potentials… Acute hepatic failure
Sedation
Fluid balance and outcome
Nutritional therapy
Tissue oxygenation and oxygen delivery
Abdominal compartment syndrome
Cardiogenic shock
Clostridium difficile
Scoring systems
Examples… :Examples… In the question on the brain-stem dead patient, too many candidates included detail of brain stem testing in their answers, which was not required. Candidates are reminded to answer the question as written; no credit will be given for irrelevant information It cannot be emphasised enough that the answer provided to the examiners is less than a page and is focused completely to the question.
Case scenario 1 :Case scenario 1 49 year old female, history of depression & anxiety found unconscious in apartment having failed to turn up for work
On arrival A&E GCS 5-6, BM = 0.4
After 50ml 50% glucose BM = 14.5 and GCS 12-14
Bruising left buttock and thigh
Tender abdomen, jaundiced, BP 75/45, HR 104, Temp 34.1
CT brain NAD, CT abdo - mild hepatomegaly, ? fatty
Labs: Lactate 10.2, Bili 27, AST 4465, ALT 1945, INR 4, Paracetamol 25, tox negative, K 1.9, Ca 0.8, PO4 0.4, Hb 10.4, WBC 15.9, Plts 102, CK 595
Questions for discussion :Questions for discussion What are the main differential diagnoses?
What other information/tests would you like?
Why is the GCS abnormal?
How do you assess fluid status and responsiveness?
What does the lactate level tell you?
Why is the B low and how will you tackle it?
How do you assess the adequacy of oxygen delivery?
Does this patient need antibiotics?
What problems are likely in the next 24-48 hours?
Acute hepatic failure :Acute hepatic failure Early death despite support
Survival with supportive therapy (liver regeneration)
Unlikely to survive with supportive therapy alone
candidate for emergency transplant
NOT candidate for emergency transplant INFO “Life-threatening multi-system illness resulting from massive liver injury. The defining clinical symptoms are coagulopathy and encephalopathy occurring within days or weeks of the primary insult in patients without pre-existing liver injury”
Auzinger G, Wendon J. Curr Opin Crit Care 2008; 14: 179-188
Aetiology based therapy :Aetiology based therapy INFO
Paracetamol toxicity :Paracetamol toxicity INFO Enhanced risk
Excess alcohol
Enzyme-inducing drugs
carbamazepine
phenytoin,
phenobarbitone
St John's Wort
rifampicin
3. Glutathione depletion
malnutrition
eating disorders
malabsorption
HIV NAPQI Major paths Minor path
N-acetylcysteine :N-acetylcysteine INFO (1) Initially 150mg/kg in 200mL glucose 5% given over 15 minutes, then
(2) 50mg/kg in 500mL glucose 5% given over 4 hours, then
(3) 100mg/kg in 1000mL glucose 5% given over 16 hours
Referral criteria :Referral criteria INFO Non-paracetamol Paracetamol
Referral criteria - Kings College Hospital :Referral criteria - Kings College Hospital INFO Paracetamol Non-paracetamol
Clinical Issues in ALF :Clinical Issues in ALF CNS
Encephalopathy - ammonia => glutamate
Intracranial hypertension - oedema
Cardiovascular
Intravascular volume depletion
Vasodilatation
Subclinical myocardial damage (Tn > 0.1 in 66%)
Respiratory
Hypoxia - effusions, atelectasis, shunting, splinting, ALI INFO
Clinical Issues in ALF :Clinical Issues in ALF Renal
Oliguria
Acute renal impairment - drugs, hepatorenal, pre-renal, ATN, intra-abdominal hypertension
Haematological
Thrombocytopaenia and coagulopathy
Procedural bleeding possible
Spontaneous bleeding rare
Infection
Monocyte (HLA-DR), complement, Kupffer cell failure Responsible for most deaths! INFO
Useful references :Useful references INFO Kramer DJ, Canabal JM, Arasi LC. Application of Intensive Care Medicine Principles in the Management of the Acute Liver Failure Patient. Liver Transplantation 2008; 14: S85-89.
Auzinger G, Wendon J. Intensive Care Management of Acute Liver Failure. Current Opinion in Critical Care 2008; 14: 179-188.
Stravitz T. Critical Management Decisions in Patients with Acute Liver Failure. Chest 2008; 134: 1092-1102.
Case scenario 2 :Case scenario 2 56 year old male, history of IHD/PVD/smoker/MI/EF 35%
Admitted to ICU following emergent leaking AAA repair…complicated by intraoperative ST depression and hypotension
On arrival ICU BP = 90/45, HR 121 SR, NA @ 0.5 mg/kg/min, lactate 5
CVP 14, pO2 11 on 70% O2 with PEEP 5, creps bilaterally
ECG: infero-lateral ST depression
In theatre 4 L crystalloid, 2 L tetraspan, 6 packed cells, 2 FFP
Abdomen distended and tense, skin clammy
Over next 4 hours: NA increasing, lactate 8, U/O poor
Labs: Hb 9.5, Plts 85, WBC 7.9, Na 141, K 5.3, U 10.5 Creat 168, APTT 47, PT 18, fibrinogen 0.95
Questions for discussion :Questions for discussion List the main clinical issues in this case
How would you approach the respiratory failure?
What factors contribute to the hypotension/malperfusion?
What is your strategy to improve haemodynamics?
What is your target for fluid balance in the next 24 hours?
How does PPV assist the left ventricle?
What other monitors/investigations might assist you?
When would you involve the surgeons?
Cardiogenic Shock :Cardiogenic Shock Definition
Incidence
Aetiology
Pathophysiology
Therapy Clinical:
Hypotension i.e. SBP below 90 mmHg
Impaired tissue perfusion
After correction of non-cardiac factors
Haemodynamic:
Cardiac index 18 mm Hg or PCWP > 16
Urine output 2100 dynes-sec·cm–5 INFO
Incidence & Mortality :Incidence & Mortality [1] The CREATE-ECLA Trial Group. Effect of glucose-insulin-potassium infusion on mortality in patients with acute ST-segment elevation myocardial infarction: the CREATE-ECLA Randomized Controlled Trial. JAMA 2005; 293: 437–446.
[2] Babaev A, Frederick PD, Pasta DJ, et al. Trends in management and outcomes of patients with acute myocardial infarction complicated by cardiogenic shock. JAMA 2005; 294:448–454.
[3] Jeger RV, Harkness SM, Ramanathan K, et al. Emergency revascularization in patients with cardiogenic shock on admission: a report from the SHOCK trial and registry. Eur Heart J 2006; 27:664–670.
[4] Chen ZM, Pan HC, Chen YP, et al. Early intravenous then oral metoprolol in 45,852 patients with acute myocardial infarction: randomized placebo controlled trial. Lancet 2005; 366:1622–1632. INFO
Echo indicators of mortality :Echo indicators of mortality INFO
Pathophysiology :Pathophysiology INFO
Cardiogenic Shock :Cardiogenic Shock Definition
Incidence
Aetiology
Pathophysiology
Therapy INFO
Pathophysiology :Pathophysiology Target for therapy? At least 20% of CS patients have SIRS and low SVR INFO
Therapy - Reducing iNOS :Therapy - Reducing iNOS “Excessive NOS results in high levels of nitric oxide that, in turn, lead to inappropriate systemic vasodilatation, progressive systemic and coronary hypoperfusion, and myocardial depression” Effect of Tilarginine Acetate in Patients With Acute Myocardial Infarction and
Cardiogenic Shock - The TRIUMPH Randomized Controlled Trial. JAMA 2007; 297: 1657-1666 INFO
Cardiogenic Shock: Therapy :Cardiogenic Shock: Therapy Optimise volume / oxygenation / rhythm
Inotropic agents & vasopressors
b agonists
a agonists
PDE III inhibitors
LEVOSIMENDAN
sensitizes myocardial contractile proteins to calcium
independent of sympathetic NS and so NO increase in MVO2
Prolonged action beyond infusion duration
IABP
PCI INFO
Abdominal compartment syndrome :Abdominal compartment syndrome Increasingly recognised problem
LOOK for it! - don’t forget “medical” ICU patients
Thinks about screening if
Large volume resuscitation > 3.5 L in 24 hours
Abdominal Surgery/Primary Fascial Closure
Coagulopathy or polytransfusion
Pulmonary, renal or hepatic dysfunction
Acidosis
Hypothermia
Ileus
Physical exam is NOT accurate INFO
Intra-abdominal pressure :Intra-abdominal pressure INFO Abdominal perfusion pressure = MAP - IAP (aim > 60 mmHg)
Abdominal CompartmentSyndrome :Abdominal CompartmentSyndrome INFO ACS = sustained IAP > 20 mmHg (with or without APP < 60 mmHg) that is associated with new organ dysfunction/failure
World Society of the Abdominal Compartment Syndrome (www.wsacs.org)
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Case scenario 3 :Case scenario 3 25 year old female, “fit and well”
Admitted to ICU after 6 day prodromal illness (fever, aches) followed by confusion, shortness of breath and now fluid-resistant hypotension
Intubated in A&E as hypoxic and combative, received 3 L saline
On arrival ICU BP = 75/40, HR 135 SR, NA @ 0.7 mg/kg/min, lactate 7, CVP 9, pO2 9 on 100% O2 with PEEP 7, creps bilaterally
Temperature 39.7, flushed
Over next 2 hours: NA increasing, lactate 9, U/O poor
Labs: Hb 10.5, Plts 65, WBC 27.9, Na 137, K 3.3, U 12.5 Creat 138, APTT 47, PT 19, fibrinogen 1.0, CK 290
Q: Comments on Xray appearance? :Q: Comments on Xray appearance?
Slide 37:What is the differential diagnosis?
What are the possible sources?
What are the principles of management?
Describe your haemodynamic targets and approach
How do you make the diagnosis of ARDS?
What ventilator settings will you choose?
What principles guide your ventilation strategy?
What are your ventilator targets? Questions for discussion
Sepsis: Know what you mean… :Sepsis: Know what you mean… SIRS - 2 or more of the following
Temperature > 38 or 90 bpm
Respiratory rate > 20/min or pCO2 12000/mm3 or 10% bands
Sepsis
Systemic response to infection
SIRS + infection
Severe sepsis
Sepsis + organ dysfunction, hypotension or hypoperfusion
May be oliguria, encephalopathy or lactate rise
Septic shock
Sepsis induced SBP 40 mmHg
PLUS hypoperfusion despite adequate fluid resuscitation
i.e. sepsis-induced hypotension requiring vasopressors INFO
Principles of septic shock management :Principles of septic shock management Initial resuscitation
Fluid resuscitation - ? EGDT (Rivers)
Diagnosis
Antibiotic therapy
Source identification and control
Haemodynamic and adjunctive therapy
Vasopressors and/or inotropes (know characteristics & pros and cons)
Steroids (know relative adrenal insufficiency principles)
rhAPC (know trials and controversies)
Other support
Blood products
Safe ventilation in ALI/ARDS (know ARDSNet etc.)
Sedation (know sedation breaks)
Glucose control (know controversies medical v surgical pts)
RRT
DVT prophylaxis
Stress ulcer prophylaxis (relationship to Cdiff?)
Limitation of therapy? INFO
When septic shock isn’t just septic… :When septic shock isn’t just septic… TOXIC SHOCK SYNDROME
Toxins act as “superantigens”
Activate up to 30% of neutrophils (normal MSOF
Differences in treatment from “simple” septic shock
Prodromal illness…source can be subtle => LOOK HARD
Remember vaginal infections
Predominant organisms
S. aureus (often blood culture negative)
Menstrual and non-menstrual forms
May not have protective antibodies
Group A strep (majority blood culture positive)
Therapeutic principles
As for septic shock BUT
Toxin suppressing antimicrobial: clindamycin or linezolid
Immunoglobulin 1g/kg then 0.5 g/kg for 4-5 days INFO
Q: Nutrition - how and why? :Q: Nutrition - how and why? Your patient stabilises over the next 18-24 hours
She weighs 60 kg at baseline
She hasn’t eaten at home for 5 days
How are you going to support her nutrition?
What are her requirements?
How much do you give her today?
How do you manage “intolerance”
Why is nutrition important?
Nutrition Support/Therapy :Nutrition Support/Therapy INFO When to feed = EARLY ( 10000 kcal deficit correlates with poor outcome
= 5 days off food in sepsis!!
every day in ICU without feeding is a day closer to death!
Nutrition Support/Therapy :Nutrition Support/Therapy INFO Nutrition modulates stress response
Nutrition modulates systemic immunity
Gut surface area = tennis court!!
Exposure to and in harmony with trillions of organisms
GALT = gut associated lymphoid tissue - appropriate exposure enhances systemic immunity
Nutrition Support/Therapy :Nutrition Support/Therapy INFO No feeding + systemic illness = leaky gut (BAD)
Antibiotics = higher pH and less anaerobic flora (BAD)
Anaerobes produce substances which enhance immune response (GOOD)
Fewer anaerobes = poor WBC function and more systemic infection (BAD)
Leaky gut = bugs and cytokines (BAD)
GUT-LUNG conduit: bugs/cytokines via thoracic duct and heart to pulmonary capillary bed => lung inflammation (BAD)
Nutrition Support/Therapy :Nutrition Support/Therapy INFO Short-chain fatty acids related to anaerobe levels
Short-chain fatty acids are colonocyte fuel
WBCs have receptors for SCFA = imprived function!
Attention to nutrition/antibiotics and pre/probiotics
What and how much? :What and how much? INFO Energy (kcal)
generally 25 kcal, up to 35 kcal/kg
start at 25-35% of requirement if refeeding syndrome risk
Protein
generally 1.25 g/kg
no need for < 1g/kg in acute liver disease
Lipids
? omega-3 FA’s in ARDS (favour anti-inflammatory eicosanoids)
Trace elements
selenium in sepsis?
Amino acids
arginine (vasodilatory)
glutamine (enterocyte fuel and ? better WBC function in trauma)
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www.criticalcarenutrition.com :www.criticalcarenutrition.com
Fluid Balance & OutcomeIt’s not IF they should be dry... it’s WHEN :Fluid Balance & OutcomeIt’s not IF they should be dry... it’s WHEN