Managing the ICU Patient

Question 1

Two criteria for selecting patients for surgery

Answer 1

• Patient’s pathology (diagnosis, staging, etc.)
• Patient’s overall health (i.e, are they going to be able to recover from the grave wounds we plan to inflict upon them?)

Question 2

Series of events from intake to discharge

Answer 2

Question 3

indications for ICU

Answer 3

• There are essentially three indications for ICU….*
  
  • Respiratory insufficiency
  • Hemodynamic (cardiovascular) insufficiency
  • Depressed consciousness or coma
    
    • * or the threat of these conditions!

Question 4

ICU notes

Answer 4

• 1. Identify patient
     * Name, age, days in ICU, primary team
• 2. Main problem (why admitted), new problems
• 3. Background information
     * Medical history, ICU history
• 4. Current problems
• 5. Physical findings (I’s & O’s, labs, vitals, exam)
• 6. Evaluation of patient by system
     * Observation, intervention, impression (stable?)
• 7. Overall impression
• 8. Plan for the next 24 hours

Question 5

what are the systems

Answer 5

1. Respiratory
2. Cardiovascular
3. Neurological
4. GI and Nutrition
5. Hematology
6. Electrolytes
7. Renal
8. Infectious Disease

Question 6

respiratory

Answer 6

• ICU patients are often on mechanical ventilation.
• Require a lot of interventions.
  
  • Oxygenation, vent settings, sedation, suctioning, etc.
• Patient will already be intubated with an endotracheal tube.
• This is a requirement for using the ventilator with positive pressure ventilation
• Real time observations from the patient will guide ventilator therapy.
• Respiratory rate, O2 sat, arterial blood gases.
• Review the vent history; is the patient improving? Declining?
• Long-term vent therapy requires that a patient undergo a tracheostomy.

Question 7

three main types of ventilation modes

Answer 7

• Assist-control (AC)
• Intermittent Mandatory Ventilation (IMV/SIMV)
• Pressure Support Ventilation (Spontaneous)
• Breathing is protected, airway is protected
• Modes: frequency that it pushes air into the patient

Question 8

Assist-control ventilation

Answer 8

• Fixed respiratory rate and fixed tidal volume
• Patient can initiate breaths, and each gets full TV
• Required for patients in deep coma or sedation
• Deep coma/sedation is required for AC

Question 9

intermittent mandatory ventilation (IMV/SIMV)

Answer 9

• Periodic breaths at set rate (minimum)
• Patient can initiate breaths above set rate
• Patient determines TV for spontaneous breaths, and breaths are supported by positive pressure.
• More comfortable for patients who are more awake.

Question 10

Pressure support ventilation (spontaneous)

Answer 10

• Patient initiates every breath (no set rate)
• Breaths are supported by positive pressure
• Least invasive, most comfortable for awake patients
• Used when weaning from mechanical ventilation

Question 11

how to document (or order) mechanical ventilation

Answer 11

• Mode RR(actual) TV FiO2 PEEP PSV
• Example:
• SIMV 12(14) 400 50% PEEP=5 PSV=8
• RR – you put what its set to and what you actually observe

Question 12

Mode

Answer 12

• AC
• IMV/SIMV
• Spontaneous (Spont)

Question 13

Respiratory Rate (breaths per minute)

Answer 13

• Not just important for oxygenation.
• The rate controls how much CO2 is being expired.
• The higher the rate, the more CO2 is removed.

Question 14

Tidal volume

Answer 14

• (milliliters per breath)
• Normal tidal volume is about 6ml/kg (e.g., 80kg person would have a normal TV of 480ml).
• Higher volumes are associated with barotrauma.
• With critically ill patients, the general practice is low volume ventilation, with tidal volumes as low as 4ml/kg.

Question 15

fractional concentration of inspired oxygen (FiO2)

Answer 15

• Expressed as a percentage.
• Start with 100% when beginning mechanical ventilation, and titrate down, monitoring O2 saturation.
• >60% for 48 hours can be toxic.

Question 16

Positive end-expiratory pressure (PEEP)

Answer 16

• Residual positive pressure at the end of expiration.
• Keeps alveoli open.
• Useful in people with “stiff lungs” (e.g., ARDS).
• 5 cm H2O is helpful in promoting oxygenation and reducing barotrauma.
• High PEEP measurement is an indication that the person is not ready to be off ventilation

Question 17

pressure support (PSV)

Answer 17

• Used in IMV and spontaneous ventilation.
• Positive pressure applied with patient-initiated breaths.
• Helps to overcome the resistance of the ventilator circuit (“sucking through a straw”).
• This overcomes the narrowness of the tube

Question 19

three things needed for cardiovascular system to work

Answer 19

• A functioning pump
• Sufficient fluid volume
• Regulated resistance

Question 20

Cardiovascular shock

Answer 20

• Pump dysfunction
  
  • Cardiogenic shock
• Volume depletion
  
  • Hypovolemic shock
• Resistance dysfunction
  
  • Septic/neurogenic/anaphylactic shock

Question 21

three things to know when managing shock

Answer 21

• Cardiac output (SV x HR)
• Central Venous Pressure (CVP)
  
  • CVP = what is their fluid status
• Systemic Vascular Resistance (SVR)

Question 22

cardiogenic shock

Answer 22

• ↓ Cardiac output
• ↑ Central venous pressure
• ↑ Systemic vascular resistance

Question 23

how to manage cardiogenic shock

Answer 23

• Dobutamine (start 0.5mcg/kg/min, to max of 40mcg)
  
  • Inotropic, so will ↑CO (by ↑ stroke volume)
  • Patient will experience ↓ SVR, due to baroreceptor response
  • Does not ↑ arterial BP, so may need additional drugs

Question 24

hypovolemic shock

Answer 24

• ↓ Cardiac output
• ↓ Central venous pressure
• ↑ Systemic vascular resistance

Question 25

how to treat hypovolemic shock

Answer 25

• GIVE THE PATIENT FLUID!
• Total body fluid: 80kg man (48L), 60kg woman (30L).
• Blood volume: 80kg man (5.3L), 60kg woman (3.6L).
• Can lose up to 15% of blood volume and compensate.
• Start to get into trouble between 15 and 30%.
• After 30%, will go into shock.

Question 26

Volume replacement

Answer 26

• Calculate fluid loss (% blood loss x total)
• Give four (4) times the loss in IV crystalloid
• Example: 35% x 5.3L = 1.9L, so replace with 7.5-8L
• Target is CVP between 5-10mm Hg (12-15 can mean fluid overload)
• Follow electrolytes and Hgb during replacement.

Question 27

Septic/neurogenic/anaphylactic shock

Answer 27

• ↑ Cardiac output
• ↓↔ Central venous pressure
• ↓ Systemic vascular resistance

Question 28

how to treat septic/neurogenic/anaphylactic shock

Answer 28

• Dopamine (start 1.0mcg/kg/min, titrate to effect)
  
  • Dose dependent response.
  • Low dose (1-5mcg): specifically increases blood flow to renal, mesenteric, and cerebral regions, by increasing SVR in other regions.
  • Intermediate dose (5-10mcg): stimulates β receptors in heart, ↑ cardiac output.
  • High dose (>10mcg): stimulates α receptors in systemic and pulmonary circulation, increasing SVR while preserving CO, thus helping to correct hypotension.
  • Complications: tachycardia at intermediate doses, and ischemic limb necrosis even at low doses (consider prompt α blocker, e.g., phentolamine).

Question 29

hypertensive emergency

Answer 29

• Give anti-hypertensives
  
  • Drips of nitroprusside/nicardipine/clevidipine/esmolol
  • PRN labetalol or hydralazine
  • Wean off and transition to longer-acting PO meds

Question 30

Pulmonary artery (swan ganz) catheter

Answer 30

• Invented in 1970, was the first device to measure hemodynamic phenomena in real time.
• Several studies have shown there to be NO improved outcomes when using PA catheters.
• Echocardiography and other measures are safer.

Question 31

Closed head injury

Answer 31

• Start with ABCs
• Depending on injury, may need invasive monitoring to monitor intracranial pressures (ICP).
• The problem is that trauma causes edema, which leads to ↑ ICPs, which leads to ↓ in oxygen delivery to brain tissue and/or herniation of brainstem through the foramen magnum (i.e., brain death).
• If blood cant get into the brain, then the brain cant get oxygen and the brain begins to die – this can then cause the brain to push out through the foramen magnum – this will compress the brainstem against the skull and will prevent you from ever waking up again

Question 32

The goal for neurological patients

Answer 32

• The goal is to keep oxygen flowing to brain so it can heal.
• Need to maintain favorable pressure gradient, called cerebral perfusion pressure (CPP).
• CPP = MAP - ICP
• So, for critical head injuries, we need to be able to monitor (and control) both intracranial pressure AND blood pressure.
• Goal CPP is often around 60mm Hg (may vary)
• Goal ICP is generally <22mm Hg
• Thus, MAP should be maintained at ≥ 80mm Hg
• To maintain CPP, we can lower ICP (preferable), or raise MAP (less preferable)
• Other methods of lowering ICP include paralysis, mannitol, and surgical decompression (definitive)
• You can also use hypertonic saline to decrease the pressure

Question 33

ICP monitoring

Answer 33

• Camino Bolt
  
  • Threaded, is screwed into skull.
  • Rests just under dura
  • Provides real time ICP data

Question 34

Licox monitor

Answer 34

• Inserted like a Camino bolt
• Measures O2 content of blood
• Considered more useful than Camino, because it measures direct oxygenation, rather than perfusion pressures (which only correlate with oxygenation).

Question 35

ventriculostomy

Answer 35

• A catheter inserted into the lateral ventricle
• Provides real time ICP monitoring
• Also provides means to drain CSF from brain, which can reduce ICP
• May be used in conjunction with Licox
• GOLD STANDARD FOR CRANIAL PRESSURE MONITORING

Question 36

subarachnoid hemorrhage and aneurysms

Answer 36

• Subarachnoid hemorrhage and aneurysms
• “Worst headache of my life.”
• May be traumatic, or due to an aneurysm.
• Aneurysms are worse.
• A weak point in a cerebral artery.
• Often asymptomatic.
• Usually devastating.
• 50% never make it into the hospital.
• 50% in hospital die.
• Once in ICU, these patients are placed on a protocol.
• Critical BP control, neuro checks, seizure prophylaxis, vasospasm prophylaxis.
• The goal is to repair the aneurysm before it bleeds again.
• Surgery (clipping) or interventional radiology (coiling) are the methods.
• Once repaired, patient stays in ICU.
• High risk for vasospasm, so gets neuro checks, HHH (hypervolemic-hypertensive-hemodilution) therapy, and nimodipine.
• These patients get a lot of IV fluid, and are allowed to have SBP as high as 200, for a week or longer.
• Vasospasm requires emergent transluminal balloon angioplasty.

Question 37

the big three

Answer 37

• Respiratory insufficiency, cardiovascular insufficiency, and neurological injury.
• Know your history.
• Read the chart, especially the previous notes.
• Sweat the “small stuff.”

Question 38

the “small stuff”

Answer 38

• Just because they’re “small” doesn’t mean they’re not critical to keeping your patient moving rightward.
  
  • It does mean that they tend to kill your patient slowly, rather than quickly.
  • The “Small Five”
  • GI/nutrition, hematology, electrolytes, renal, infectious disease

Question 39

gut and nutrition

Answer 39

• Most ICU patients are too obtunded to eat. They’re either NPO (on purpose) or they need nutrition.
• Nutrition is critical to surviving a stay in the ICU.
• Patients can be fed through NGT (at first), Dobhoff tubes (longer term), or G-tubes (longest term).
• Tube feeds are recommended by our nutritionists.
• Prophylaxis

Question 40

hematology

Answer 40

• ICU patients tend to become anemic.
• Hemorrhage, consumption, malnutrition, phlebotomy
• We follow Hgb; if it falls below 8.0, we consider transfusion.
• We also follow coags (INR), and correct as needed.
• Prophylaxis

Question 41

electrolytes and renal

Answer 41

• Following I’s & O’s
  
  • In: IVF (including meds), TF, oral
  • Out: UOP, BM, drains, emesis, NG output, insensate
    
    • Insensate fluid loss in a healthy adult: 400ml H2O from lungs, 400ml H2O from skin
• Follow over 24°, and over multiple days. We prefer that I’s & O’s (plus insensate losses) are balanced.

Question 42

renal protocol

Answer 42

• For renal, we follow urine output, and blood urea nitrogen and creatine. Minimum UOP should be ≥20ml/hr. BUN/Cr should not be climbing.
• Pre-renal: ↓ blood flow to kidney (hypovolemia, renal artery obstruction)
• Intrinsic: damage to kidney (drugs, ischemia, infection)
• Post-renal: obstruction of urinary tract (stones, catheter, BPH)

Question 43

hyponatremia

Answer 43

• May be chronic in ICU patients (125-130). Can be caused by malnutrition, drug side effects, fluid overload.
• Best to treat the underlying problem first.
• If really low (<120) and symptomatic (nausea, malaise, headache → coma, seizures, arrest), replace sodium, with continuous infusion of 3% (hypertonic) NaCl IV. Start oral repletion.

Question 44

hypernatremia

Answer 44

• Hypernatremia (>145)
• Usually caused by hypovolemia, renal disease, or diabetes insipidus (DI).
• Give more fluid, but NOT normal saline.
• Slow correction is the general rule.
• DDAVP is indicated some cases of DI (patients will have ↑ UOP, ↓ urine SG, and ↑ serum osmolality).

Question 45

hypokalemia

Answer 45

• Patients generally asymptomatic until ≤ 3.0
• Correct the underlying disorder, and give K+
• Oral is preferable (KCl tabs, or KCl elixir). IV is frequently necessary. 20-40mEq at a time.
• Prophylaxis

Question 46

hyperkalemia

Answer 46

• Mild (<6.0): Give loop diuretic (40-80mg Lasix), and Kayexalate (30gm in 50ml of 20% sorbitol PO or PR)
• Moderate (<6.0-7.0): Sodium bicarb, insulin with D50, albuterol nebs)
• Severe (>7.0 or lower w/ EKG changes): CaCl or calcium gluconate IV, hemodialysis

Question 47

hypomagnesemia

Answer 47

• Normal range is 1.7-2.3
• Very low levels (≤ 0.7) can cause fatal arrhythmias
• Seen in drinkers
• Correct with MgSO4 1-2gm IV slow push
• Prophylaxis

Question 48

infectious disease

Answer 48

• Infection can be the cause of a patient’s critical condition, or a complication. Every ICU patient is at risk for a life-threatening infection.
• Pay special attention to WBC and temp in writing your note. Also follow antibiotics: What are they on now? What have they been on? How long?
• If patient has a new fever or ↑ WBC, then get “pan cultures” (blood, sputum, urine) and CXR to start.

Question 49

GI/nutrition prophylaxis

Answer 49

• Feed patient as soon as you can. Give them a multivitamin to help prevent electrolyte problems.
• Most, if not all, ICU patients need to be on a proton pump inhibitor (Nexium, Pepcid). Especially patients who are NPO, on steroids, or head injured.
• Bowel regimen: stool softener (colace), stimulant laxative (senna), suppositories (dulcolax).

Question 50

hematology prophylaxis

Answer 50

• Deep venous thrombosis and pulmonary embolism
• Every patient should be wearing sequential compression devices (aka “pumpy leg things”).
• Every patient should get prophylactic heparin or LMWH when hemodynamically stable.
• Confirm this every day, even if already ordered.

Question 51

medications

Answer 51

• Review all medications every day.
• Which meds can or should be removed?
• Which should the patient be on?
• Do any meds need to be renewed?
• Do we need to check serum drug levels on anything?

Question 52

sedation

Answer 52

• Does the patient have adequate sedation and pain control?
• Is the patient over-sedated or over-narced?
• Always document what meds are being used, and the usage history of these meds.
• Some meds have toxic profiles when used for a long time (e.g., propofol, toradol); check labs accordingly.

Question 53

integumentation

Answer 53

• Skin breakdown is a huge concern among bedbound patients.
• Is the patient being turned? Is there any sign of skin breakdown?
• Do they need a special mattress (e.g., airflow mattress)?
• Any new rashes or lesions?

Question 54

ICU note summary

Answer 54

1. Identify patient
2. Main problem (why admitted), new problems.
3. PMHx, ICU Hx
4. Current problems
5. Vitals, vent status, I’s & O’s, labs, meds, physical exam
6. Overall impressions

• Respiratory
• Cardiovascular
• Neuro
• GI/Nutrition
• Heme
• FEN/Renal
• ID
• Prophylaxis

7. General plan for the next 24 hours