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Introduction to critical care USIntroduction to critical care US

SAH & RNSH 2011SAH & RNSH 2011

Critical Care Ultrasound CourseCritical Care Ultrasound Course

Goals of today's courseGoals of today's course

• Understand critical care ultrasoundUnderstand critical care ultrasound

• Understand its limitations (& your own)Understand its limitations (& your own)

• Learn the basics of lung, IVC and cardiac Learn the basics of lung, IVC and cardiac sonographysonography

• Learn the arrest / shock / breathless algorithmsLearn the arrest / shock / breathless algorithms

• Perform a 3-minute screenPerform a 3-minute screen

A real caseA real case(My road to Damascus)(My road to Damascus)

• shockedshocked 30 yr old male 30 yr old male

• breathless & severe chest painbreathless & severe chest pain

• mildly mildly febrilefebrile, heart racing, heart racing

• unresponsive to O2 / fluid / antibioticsunresponsive to O2 / fluid / antibiotics

• Recovering from a common coldRecovering from a common cold

• no RFs for the usualsno RFs for the usuals

• getting worse in front of usgetting worse in front of us

Initial investigationsInitial investigations

• CXR clearCXR clear

• ECG non specificECG non specific

• ABG markedly abnormal gas exchangeABG markedly abnormal gas exchange

Atypical pneumonia?Atypical pneumonia?Or a PE?Or a PE?

OK, letOK, let’’s get a scan.s get a scan.

• Too unstable for CT / VQ scanToo unstable for CT / VQ scan

• Cardiology: Cardiology: ‘‘too busytoo busy’’

• Radiology: Radiology: ‘‘we donwe don’’t do echot do echo’’

#*%* !!!#*%* !!!

Get out the ED US machine!Get out the ED US machine!

• LungsLungs• IVCIVC• HeartHeart• Leg veinsLeg veins

Lungs clearLungs clear

Non-collapsing IVCNon-collapsing IVC

RV > LVRV > LV

DVTDVT

ResultsResults

• Lungs clearLungs clear

• Distended IVCDistended IVC

• High pressure dilated RV > LVHigh pressure dilated RV > LV

• DVTDVT

• Diagnosis?Diagnosis?

Massive PEMassive PE

• Working diagnosis: massive PE (not atypical Working diagnosis: massive PE (not atypical pneumonia)pneumonia)

• Treatment: ED thrombolysisTreatment: ED thrombolysis

• Rapid improvementRapid improvement

Essential features of any Essential features of any bedside test in critical carebedside test in critical care

• Improves accuracy of diagnosis in the critically ill Improves accuracy of diagnosis in the critically ill (prehospital, ED, ICU)(prehospital, ED, ICU)

• Guides treatment / resuscitation / proceduresGuides treatment / resuscitation / procedures

• RapidRapid

• Simple Simple

• Repeatable Repeatable

BSLECG

O2 Sats

Bedside Critical Care US (CCUS)

Why?Why?

• A simple 3-minute ultrasound can assist in diagnosis A simple 3-minute ultrasound can assist in diagnosis and resuscitationand resuscitation

• It may not give you the final diagnosisIt may not give you the final diagnosis

• But it buys you the time to perform a more detailed But it buys you the time to perform a more detailed assessment once stabilisedassessment once stabilised

• EG a focused TTEEG a focused TTE

• EG a CT scanEG a CT scan

What is critical care US?What is critical care US?

• A rapid, A rapid, patientpatient-focused-focused bedside US scan bedside US scan

• Initial rapid scan: lungs / IVC / heart (curved probe) / Initial rapid scan: lungs / IVC / heart (curved probe) / other areas as appropriateother areas as appropriate

• Then, after initial resuscitation, a more rigorous look Then, after initial resuscitation, a more rigorous look at specific areas as indicated:at specific areas as indicated:

• Heart / Lungs / Abdomen / Leg veinsHeart / Lungs / Abdomen / Leg veins

Why isn't focused TTE enough?Why isn't focused TTE enough?

Focused TTE

1. Just looks at heart

2. Cardiac probe / preset

3. Difficult windows

4. Slow learning curve

5. Takes several minutes

6. No cardiac windows = no information

7. Adapted from formal TTE

Rapid CCUS screen

1. Heart / lung / IVC / veins

2. Curved probe / abdo preset

3. Simple windows

4. Rapid learning curve

5. Takes 3 minutes

6. Works even if you can't see the heart / IVC

7. Purpose-built & validated for critical care

Does the screen really take 3 Does the screen really take 3 minutes?minutes?

Why isn't focused TTE enough?Why isn't focused TTE enough?

• Cardiac sonographer: 'the DDx between pericardial & Cardiac sonographer: 'the DDx between pericardial & left pleural fluid can be subtle'left pleural fluid can be subtle'

Duh! Just look at the left thoraxDuh! Just look at the left thorax

This is why focused TTE isn’t This is why focused TTE isn’t enoughenough

• Cardiologists look after the heart Cardiologists look after the heart →→ echocardiography just looks at the heartechocardiography just looks at the heart

• Critical care doctors look after the entire patient Critical care doctors look after the entire patient →→ so so our US scan should look at the our US scan should look at the patientpatient, not just an , not just an organorgan

Whole-bodyWhole-body ultrasound ultrasound

Current standard of critical care Current standard of critical care ultrasoundultrasound

LUNGLUNG

IVCIVC

HEARTHEART+other regions as +other regions as

appropriateappropriate

An important noteAn important note

• Cardiologist: 'Why do you want an urgent echo? Echo Cardiologist: 'Why do you want an urgent echo? Echo can't rule out a PE'can't rule out a PE'

• ED physician: 'But this will rule out a ED physician: 'But this will rule out a massivemassive PE' PE'

If it's a PE making the patient critically unwell, then it If it's a PE making the patient critically unwell, then it won't be a small one.won't be a small one.

Top tip: bloody sick = bloody obvious

We're not looking for small pneumothorax or mild CCF('rule-in', not 'rule-out')

If the patient is unstable, the US signs should be obvious

What this isn'tWhat this isn't

A formal echocardiogram

• It doesn't use M-mode or Doppler

• It doesn't look for subtle disease

• It includes other windows & other organs to synthesize the answer

The holy grail

• It is not validated in those with minor degrees of illness (eg mild CCF)

• It will sometimes be wrong in the critically ill

• It's just another tool

Limitations of critical care USLimitations of critical care US

• Algorithm: only validated in critically unwell Algorithm: only validated in critically unwell patientspatients

• Patient: suboptimal position & still being Patient: suboptimal position & still being resuscitated!resuscitated!

• Time (none!)Time (none!)

• SonographerSonographer• Image acquisitionImage acquisition• Image interpretationImage interpretation

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So: the golden rulesSo: the golden rules

1. 1. 'Resus-only': 'Resus-only': Patient must be critically unwell: shocked / Patient must be critically unwell: shocked / breathless / peri-arrest. That's because the US signs of breathless / peri-arrest. That's because the US signs of some of these diseases are only reliably present if some of these diseases are only reliably present if severesevere eg eg massivemassive PE, PE, severesevere pneumonia. If formal studies are pneumonia. If formal studies are needed after resus, get them.needed after resus, get them.

2. Clinical context is paramount. 2. Clinical context is paramount. Make a differential diagnosis Make a differential diagnosis list before you switch on the machine. All data must be list before you switch on the machine. All data must be considered (eg FBC with Hb = 4).considered (eg FBC with Hb = 4).

3. Only ask questions that you can answer. 3. Only ask questions that you can answer. Leave the fancy Leave the fancy stuff (eg valve disease) to others.stuff (eg valve disease) to others.

4. Repeat scans are crucial4. Repeat scans are crucial during resuscitation & each time during resuscitation & each time clinical picture changes.clinical picture changes.

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Golden rulesGolden rules

5. 90% = 100%: 5. 90% = 100%: Every test has its limitations. In a periarrest Every test has its limitations. In a periarrest patient, no study will be 100% accurate. If this bothers you, patient, no study will be 100% accurate. If this bothers you, don't practise critical care.don't practise critical care.

RNSH respiratory physician: 'Would you really thrombolyse a RNSH respiratory physician: 'Would you really thrombolyse a critically ill patient with suspected PE on the basis of critically ill patient with suspected PE on the basis of bedside US?'bedside US?'

ED physician answer: 'I spent years doing just that without the ED physician answer: 'I spent years doing just that without the benefit of US. Anything that improves my accuracy suits me benefit of US. Anything that improves my accuracy suits me fine.'fine.'

Golden rulesGolden rules

6. When in doubt, be a doctor. 6. When in doubt, be a doctor. You were a clinician before you You were a clinician before you were a sonographer. If the clinical picture & scan findings don’t were a sonographer. If the clinical picture & scan findings don’t agree, agree, believe the clinical picture.believe the clinical picture.

‘‘What would I diagnose if I didn’t have an US machine?’What would I diagnose if I didn’t have an US machine?’

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The golden rulesThe golden rules

1. 'Resus-only'1. 'Resus-only'

2. Clinical context is paramount.2. Clinical context is paramount.

3. Only ask questions that you can answer.3. Only ask questions that you can answer.

4. Repeat scans are crucial.4. Repeat scans are crucial.

5. 90% = 100%5. 90% = 100%

6. When in doubt, be a doctor.6. When in doubt, be a doctor.

7. A fool with a stethoscope will be a fool 7. A fool with a stethoscope will be a fool with an ultrasoundwith an ultrasound

Critical care USCritical care US

• It’s not the Holy Grail

• Just another tool

• Rapid

• Safe

• Accurate

• Not difficult

Thanks toThanks to

Daniel LichtensteinDaniel LichtensteinPaul AtkinsonPaul AtkinsonConn RussellConn RussellRob ReardonRob ReardonVicki NobleVicki Noble

Russell McLaughlin (for rule #7)Russell McLaughlin (for rule #7)

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ReferencesReferences Blaivas M, Lyon M, Duggal S. A Prospective Comparison of Supine Chest Radiography and Bedside Ultrasound for the Diagnosis of Traumatic Blaivas M, Lyon M, Duggal S. A Prospective Comparison of Supine Chest Radiography and Bedside Ultrasound for the Diagnosis of Traumatic

Pneumothorax. Acad Emerg Med 2005; 12(9): 844-9.Pneumothorax. Acad Emerg Med 2005; 12(9): 844-9.

• Jones AE, Craddock PA, Tayal VS, Kline JA: Diagnostic accuracy of left ventricular function for identifying sepsis among emergency Jones AE, Craddock PA, Tayal VS, Kline JA: Diagnostic accuracy of left ventricular function for identifying sepsis among emergency

department patients with nontraumatic symptomatic undifferentiated hypotension. Shock 24:513-7,2005. department patients with nontraumatic symptomatic undifferentiated hypotension. Shock 24:513-7,2005.

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hemodynamic compromise in critically ill patients: a prospective study. J Am Soc Echocardiogr 7:598-606,1994. hemodynamic compromise in critically ill patients: a prospective study. J Am Soc Echocardiogr 7:598-606,1994.

• Kohzaki S et al. The aurora sign: an ultrasonographic sign suggesting parenchymal lung disease. The British Journal of Radiology 76 (2003), Kohzaki S et al. The aurora sign: an ultrasonographic sign suggesting parenchymal lung disease. The British Journal of Radiology 76 (2003),

437–443437–443

Lichtenstein D. Whole Body Ultrasonography in the Critically Ill. Springer, 2Lichtenstein D. Whole Body Ultrasonography in the Critically Ill. Springer, 2ndnd ed. !st published 1992. ed. !st published 1992.

Lichtenstein D, Meziere G. A lung ultrasound sign allowing bedside distinction between pulmonary edema and COPD: the comet-tail artifact. Lichtenstein D, Meziere G. A lung ultrasound sign allowing bedside distinction between pulmonary edema and COPD: the comet-tail artifact.

Intensive Care med 1998; 24(12): 1331-4. Intensive Care med 1998; 24(12): 1331-4.

• Lim et al. Lim et al. Ring-down artifacts posterior to the right hemidiaphragm on abdominal sonography: sign of pulmonary parenchymal Ring-down artifacts posterior to the right hemidiaphragm on abdominal sonography: sign of pulmonary parenchymal

abnormalities. J Ultrasound Med.abnormalities. J Ultrasound Med.1999; 18: 403-410 1999; 18: 403-410

• Moore CL, Rose GA, Tayal VS, Sullivan DM, Arrowood JA, Kline JA: Determination of left ventricular function by emergency physician Moore CL, Rose GA, Tayal VS, Sullivan DM, Arrowood JA, Kline JA: Determination of left ventricular function by emergency physician echocardiography of hypotensive patients. Acad Emerg Med 9:186-93,2002. echocardiography of hypotensive patients. Acad Emerg Med 9:186-93,2002.

• Plummer D, Heegaard W, Dries D, Reardon R, Pippert G, Frascone RJ: Ultrasound in HEMS: its role in differentiating shock states. Air Med J Plummer D, Heegaard W, Dries D, Reardon R, Pippert G, Frascone RJ: Ultrasound in HEMS: its role in differentiating shock states. Air Med J 22:33-6,2003. 22:33-6,2003.

• Randazzo MR, Snoey ER, Levitt MA, Binder K: Accuracy of emergency physician assessment of left ventricular ejection fraction and central Randazzo MR, Snoey ER, Levitt MA, Binder K: Accuracy of emergency physician assessment of left ventricular ejection fraction and central venous pressure using echocardiography. Acad Emerg Med 10:973-7,2003. venous pressure using echocardiography. Acad Emerg Med 10:973-7,2003.

• Reissig A, Kroegel C. Transthoracic Sonography of Diffuse Parenchymal Lung Disease: The Role of comet-tail artefacts. J Ultrasound Med Reissig A, Kroegel C. Transthoracic Sonography of Diffuse Parenchymal Lung Disease: The Role of comet-tail artefacts. J Ultrasound Med 2003; 22(2): 173 -80.2003; 22(2): 173 -80.

• Rose JS, Bair AE, Mandavia D, Kinser DJ: The UHP ultrasound protocol: a novel ultrasound approach to the empiric evaluation of the Rose JS, Bair AE, Mandavia D, Kinser DJ: The UHP ultrasound protocol: a novel ultrasound approach to the empiric evaluation of the undifferentiated hypotensive patient. The American journal of emergency medicine 19:299-302,2001. undifferentiated hypotensive patient. The American journal of emergency medicine 19:299-302,2001.

• WINFOCUS WORKING GROUP 4. Shock state discussion paper, 3WINFOCUS WORKING GROUP 4. Shock state discussion paper, 3rdrd world congress on US in EM and critical care, Paris 2007 world congress on US in EM and critical care, Paris 2007

• Yanagawa Y, Nishi K, Sakamoto T, Okada Y: Early diagnosis of hypovolemic shock by sonographic measurement of inferior vena cava in Yanagawa Y, Nishi K, Sakamoto T, Okada Y: Early diagnosis of hypovolemic shock by sonographic measurement of inferior vena cava in trauma patients. The Journal of trauma 58:825-9,2005. trauma patients. The Journal of trauma 58:825-9,2005.

• http://www.uptodate.com/contents/thoracic-ultrasound-indications-advantages-and-technique?http://www.uptodate.com/contents/thoracic-ultrasound-indications-advantages-and-technique?source=preview&selectedTitle=4%7E150&anchor=H1492303#H1492303source=preview&selectedTitle=4%7E150&anchor=H1492303#H1492303

PSPS

Even if I hand't performed an US, I Even if I hand't performed an US, I probably still wouldprobably still would’’ve thrombolysed ve thrombolysed

him.him.