An Introduction to Intensive Care Medicine Dr. Sam Bampoe University College London Hospitals

Overview What can we do? Who do we admit? Basic concepts of critical care Clinical context

Critical Care Medicine

What do we do on ICU? Haemofilter Vital signs monitor Intravenous sedation Nasogastric feed Intravenous fluid pump Cardiac output monitor

What do we do on ICU? “ Maintain normal physiology using pharmacology and technology, whilst treating pathology…... I would like to begin by asking you to consider your answer to the following question: how do you secure your epidural catheters in labour? And perhaps after this talk, ask the person sitting next to you how they secure theirs; it is likely that their method will differ from yours. The consequences of unintentional epidural catheter migration are well documented - including failure of analgesia, an increased likelihood of resite and the incumbent risks which that carries, and of course a negative impact on patient experience. It is therefore perhaps a little surprising that no evidence based gold standard method of catheter fixation method exists. This may, in part, explain the wide variation in practice observed.

What do we do on ICU? Stabilise and treat Advanced and invasive monitoring Organ system support Neurological Cardiovascular Respiratory Renal Gastrointestinal and hepatic All of the above!

Who do we admit? Routine admissions High risk elective surgical patients Enhanced recovery after major surgery High risk emergency surgical patients NELA NCEPOD RCS

Who do we admit? Emergency admissions “ Critically unwell patients with a potentially reversible cause for their illness” Respiratory failure Sepsis Trauma Renal failure Post cardiac arrest

Helen 63 years old 2 week history of cough Mild/moderate COPD Productive of green sputum Mild/moderate COPD Type 2 diabetes mellitus Hypertension CKD

On examination HR 103 BP 117/72 Warm peripheries RR 28 O2 Stats 87% on 2L oxygen Coarse crepitations in right lower zone with bronchial breathing in right mid-zone

Investigations

Respiratory Failure Type 1 Type 2 Failure of oxygenation Low PaO2 Low or normal PaCO2 Type 2 Failure of ventilation (+/- oxygenation) Low or normal PaO2 High PaCO2

What should we do with this patient? Oxygen! Antibiotics Fluids Chest physio Where should we care for this patient?

Levels of care Primary vs secondary care Outpatient vs inpatient care

Levels of care Level 0 Level 1 Level 2 Level 3 Requires hospital admission - ward based care Level 1 Requiring additional monitoring, clinical input or advice (outreach) Recently discharged from ICU Level 2 Requiring single organ monitoring and support Requiring advanced monitoring Level 3 Requiring advanced organ support Two or more organ system failures

Admitted to medical HDU (level 1 care) High flow 02 – 15L Antibiotics Chest physio Nebulisers O2 SATs remain 89% RR now 40 Referred to ICU

What can we do to help? “Admit, stabilise and treat” Advanced monitoring arterial line Organ support Non invasive ventilation (NIV) 1:1 nursing Doctor always present

Non-invasive ventialtion Continuous positive airway pressure (CPAP) Alveolar splinting Improves oxygenation Bi Level positive airway pressure (BiPAP) Improves tidal volume Improves ventilation (and oxygenation)

24 hours later…...... 80% oxygen PaO2 7.7Kpa PaCO2 6.1Kpa RR 40 Patient feels exhausted and drowsy What now?

Invasive ventilation Indications Life threatening hypoxaemia Failure of NIV Depressed conscious level GCS < 8 Airway protection eg. Burns Severe dyspnoea

Back to ICU…... Inspired oxygen now 50% O2 sats 90% Pa02 8.7 HR 125 BP 77/47 T38.9

SEPSIS 150,000 cases per year 44,000 deaths

Sepsis kills!

The Sepsis Six Oxygen Blood cultures Antibiotics Fluids Lactate 7.6% increase in mortality for every hour delay in giving antibiotics Oxygen Blood cultures Antibiotics Fluids Lactate Urinary catheter

Septic Shock

Cardiovascular physiology BP = CO x TPR CO = SV x HR BP = (SV x HR) x SVR We can measure these values using cardiac output monitoring

Managing refractory hypotension BP = (SV x HR) x SVR Low SV fluids Low SVR vasopressors Low CO (despite fluids) inotropes

Cardiovascular support Inotropes vs vasopressors Noradrenaline Adrenaline Dobutamine Calcium BP = (SV x HR) x SVR

Central Access

Noradrenaline complications Profound capillary vasoconstriction End-organ hypoperfusion Ischaemic injury Arrhythmias

Helen Intubated 50% oxygen requirement On Noradrenaline Cr 267 (170 baseline) Ur 17 UO 15ml/hr

Acute Kidney Injury Pre-renal Intrinsic Post-renal Hypovolaemia, hypotension, excessive vasoconstriction (vasopressors) Intrinsic Acute tubular necrosis (eg drugs), glomerulonephritis, rhabdomyolysis Post-renal Renal calculi Blocked catheter Neuropathic bladder

Helen Cr 450 K+ 5.1 Urine output 6ml/hr

Renal replacement therapy

Renal replacement therapy Indications Symptomatic uraemia Cr > 600 Hyperkalamia Acidosis (endogenous vs exogenous) Significant Oliguria/anuria Fluid management

Helen Respiratory failure Cardiovascular failure Renal failure Multi-organ failure

How long will Helen stay on ICU?

What about life after ICU?

Life after ICU…. 50% of patients who survive suffer psychological harm Clinical depression Anxiety PTSD ICU follow up clinics now increasingly common

Summary Basic principles of ICU Who we admit What we can do What happens to our patients Life after ICU

Questions?