Shock & POCUS
Disclaimer: these are personal notes and made-up cases and are meant for shock and POCUS interpretation practice and NOT meant as recommendations or guidelines for specific patient care.
Get familiar with POCUS in shock here: https://resus-pocus.firebaseapp.com/Basics/cardiac_windows/probe/
Start with the ultrasound basics, then go to lung imaging, then cardiac windows.
Once comfortable acquiring those images, work on volume intolerance and cardiac function.
If mastering only a few cardiac function tests, master the VTI, the E-point septal separation, and the TAPSE first.
POCUS images are taken from the creative commons POCUS Atlas: https://www.thepocusatlas.com/
Table of Contents
Approaching Shock
Always keep the "SHOCk" mnemonic in mind when working up a patient.
Causes of Septic/distributive shock:
Sepsis
Anaphylaxis
Sterile inflammation (pancreatitis, amniotic or fat embolism, cytokine release syndrome, etc...)
Neurogenic (spinal cord injury, severe TBI, neuraxial anesthesia)
Liver failure
Endocrine (adrenal insufficiency, thyrotoxicosis)
Medications (sedatives)
Causes of Hypovolemic shock:
Hemorrhage, hemorrhage, hemorrhage... (trauma, surgical, GIB)
Skin losses (burns, heat stroke)
GI losses (diarrhea, vomiting, drainage/surgical losses)
Third-spacing volume loss (pancreatitis, trauma, low-albumin)
Renal losses (diuretics, osmotic diuresis, etc...)
Low PO intake
Causes of Obstructive shock:
Tension pneumothorax
Pericardial tamponade
Pulmonary embolism
Outflow obstruction (HOCM, critical AS)
Dynamic hyperinflation (auto-PEEP)
Causes of Cardiogenic shock:
Rate/rhythm issues (ACLS issues)
RV failure (PE, pulmonary HTN)
LV failure (MI, CHF exacerbation, etc...)
Valvular failure
Toxins (AV nodal blockers, etc...)
Trauma (myocardial contusion)
Your history, exam/POCUS, and workup should consider the cardiopulmonary and systemic circuits. By the end of your exam, you should have a good idea of which part of the cardiovascular system is causing the shock state.
Evaluate how the left heart is doing (POCUS).
Evaluate how the systemic vascular resistance is doing (capillary refill, distal temperature, advanced POCUS).
Evaluate how the central venous system is doing (POCUS, JVD/CVP).
Evaluate how the right heart is doing (POCUS, JVD/CVP).
Evaluate how the lungs are doing (POCUS, CXR, SpO2).
A quick first test is looking for fluid TOLERANCE (not responsiveness). This is easily done and easily interpreted and gives you at a direct evaluation of the lungs and the central venous system while getting an indirect evaluation of the left and right heart: a failing left heart will back-pressurize the lungs and cause pulmonary edema and a failing right heart will back-pressurize the venous system.
Check the lungs for diffuse B lines, especially anteriorly where there shouldn't be dependent collapse, as well as pleural effusions.
While you're here, finish the lung exam and check for pleural sliding to rule-out a tension pneumothorax.
Check the IVC for OVERDISTENSION and LACK OF VARIABILITY that would suggest an elevated central venous pressure.
If unable to assess IVC, evaluate the internal jugular for JVD.
Next, get the apical 4/5 chamber view to get a gestalt on global function, septal movement, chamber size, and valve function (left lateral decubitus or a right sided wedge will help).
If savy, get your VTI (left heart function) and TAPSE (right heart function).
A subxiphoid view is another good view to get an idea of global function.
SHOCK mnemonic
Shock orders
Cardiopulmonary and systemic circuits
Normal Anatomy
The more you spend time looking at normal anatomy, the more you'll recognize abnormal anatomy.
Parasternal Long
Parasternal Short
Apical 4 Chamber
Apical 5 Chamber
Subxiphoid View
IVC View
Case 1a
24-year-old male with knife stab wound to the left of the sternum just below the nipple. He is speaking but stating he feels like he is going to die. He has decreased breath sounds on the left with RR 28 and Sat 90% on 2L nasal cannula. His initial blood pressure is 90/70 with a heart rate of 135. Capillary refill is delayed at 4-5 seconds. Lung, heart, and FAST ultrasound show:
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Left anterior lung
Left lateral lung
Right lung
Subxiphoid cardiac window
IVC
RUQ
LUQ
Pelvic
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What is the DRIVING cause of shock?
What are your next steps in management?
Case 1b
24-year-old male with knife stab wound to the left of the sternum just below the nipple. He is speaking but stating he feels like he is going to die. He has bilateral breath sounds, a RR 25, and a SpO2 of 92% on 2L nasal cannula. His initial blood pressure is 90/70 with a heart rate of 135. Capillary refill is delayed at 4-5 seconds. Lung, heart, and FAST show:
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Bilateral anterior lung fields
Bilateral anterior lung fields
Right lateral lung field
Subxiphoid cardiac window
IVC
RUQ
LUQ
Pelvic
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What is the DRIVING cause of shock?
Are there other physical exam findings you would expect to see?
What are your next steps in management?
Case 1c
24-year-old male with knife stab wound to the left of the sternum just below the nipple. He is speaking but stating he feels like he is going to die. He has decreased left breath sounds, a RR 28, and a SpO2 of 90% on 6L nasal cannula. His initial blood pressure is 90/70 with a heart rate of 135. Capillary refill is delayed at 4-5 seconds. Lung, heart, and FAST show:
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Left anterior lung
Left lateral lung
Right lung
Apical 4
IVC
RUQ
LUQ
Pelvic
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What is the DRIVING cause of shock?
What are your next steps in management?
Case 2
A 50-year-old male is post-operative day 5 from an ileostomy reversal with an ileocolonic anastomosis. Initial post operative course was uneventful, but now he is more tachypneic and requiring 4L nasal cannula to maintain a saturation greater than 92%. His HR is now 115 and his BP is 100/50. His capillary refill is brisk.
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Checking for fluid tolerance:
Bilateral anterior lung fields
Bilateral lateral lung fields
Would this patient be fluid TOLERANT?
IVC
Cardiac POCUS
PLA
Apical 4 Chamber
RUQ
LUQ
Pelvic
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What is your interpretation of the abdominal ultrasound?
What are your next steps for management?
Case 3
A 34-year-old woman is POD #3 after a right femoral IMN after getting hit by a car. She also had multiple nondisplaced rib fractures and a small subdural hematoma which led to holding of her DVT prophylaxis per neurosurgical request. She develops sudden onset shortness of breath and is requiring 15L via NRB to maintain an oxygen greater than 92%. Her HR is 120 and her blood pressure is 95/70. Her capillary refill is delayed and her extremities are cold.
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Checking for fluid tolerance:
Bilateral anterior lung fields
IVC
Would this patient be fluid TOLERANT?
Cardiac POCUS
PLA
PSA
Apical 4 Chamber
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
How does her POCUS, her vitals, and her recent TBI change your approach to management?
What are your next steps for management?
Case 4
A 75-year-old woman with an unknown past medical history is in the ICU after an emergent Hartman's operation for perforated Hinchey 4 diverticulitis complicated by septic shock. She has had two additional IR drains over the last few days for post-operative pelvic abscesses. Her HR is 110 and intermittently irregularly irregular, her BP is 100/45, and her saturation is 92% on 6L NC. Her admit weight was 65 kg and her current weight is 87 kg. She has mildly delayed capillary refill, and her exam is notable for 2+ pitting edema to the level of the shins as well as dependently around her hips.
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Checking for fluid tolerance:
Cephalad apical lung fields
Lateral lung fields
IVC
Would this patient be fluid TOLERANT?
Cardiac POCUS
PLA
PSA
Apical 4 Chamber
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What does her history and exam tell you about the type of shock?
Could this have been an acute problem? A worsening of an undiagnosed chronic problem?
What are your next steps for management?
Case 5
An 18-year-old female was the restrained passenger in an MVC T-bone to her side of the vehicle. She is complaining of right abdominal and chest pain. She has bilateral breath sounds but has tenderness over her right chest. Her initial BP is 90/65 and her HR is 134. She appears pale with cold extremities and her cap refill is about 4 seconds.
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
Checking fluid tolerance (lungs and IVC):
Bilateral anterior lung fields
Bilateral anterior lung fields
Bilateral anterior lung fields
Would this patient be fluid TOLERANT?
RUQ
LUQ
Pelvic Saggital
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What are your next steps for management?
Case 6a - Aerospace Case
You're evaluating an astronaut after an unplanned return due to capsule depressurization issues prior to docking with a Low Earth Orbit space station. Recovery from the water was prolonged due to an off-nominal ballistic reentry trajectory that took the crew far off the coast and resulted in a high impact velocity. Additionally, there was some concern that there was a hypergolic leak, and the crew was decontaminated prior to medical survey. She is an otherwise healthy 43-year-old woman who is stating that she is lightheaded and short of breath, but she denies chest pain or cough. The recovery craft is too loud to auscultate effectively. Initial automated blood pressure is measured at 90/60 and her HR on palpation and on the monitor is 120. Her RR is 26 and her SpO2 is 92% on 6L nasal cannula. She is also complaining of right knee pain and numbness on aspects of her right foot. While the paramedic is establishing IV access and hanging a liter of crystalloid, you perform an ultrasound assessment of the astronaut to further determine the cause of her elevated shock index.
What could be contributing to her vital sign changes?
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
What could be contributing to her shortness of breath?
What could be contributing to her knee and right foot complaints?
RUQ
LUQ
Pelvic
Subxiphoid
Left anterior lung fields
Right apical anterior lung field
Right anterior 5th intercostal space
IVC
Apical 4 chamber
What is the differential now based on the US imaging findings?
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What are the management considerations in the austere recovery setting?
What is the correct disposition for this patient based on all of her symptoms?
Case 6b - Aerospace Case
You're evaluating an astronaut after an unplanned return due to capsule depressurization issues prior to docking with a Low Earth Orbit space station. Recovery from the water was prolonged due to an off-nominal ballistic reentry trajectory that took the crew far off the coast and resulted in a high impact velocity. Additionally, there was some concern that there was a hypergolic leak, and the crew was decontaminated prior to medical survey. She is an otherwise healthy 43-year-old woman who is stating that she is lightheaded and short of breath. She also is mildly diaphoretic, pale, and has had multiple rounds of emesis. The recovery craft is too loud to auscultate effectively. Initial automated blood pressure is measured at 90/60 and her HR on palpation and on the monitor is 120. Her RR is 18 and her SpO2 is 96% on 2L nasal cannula. She also endorses that she had some right knee pain initially during descent, but that it has improved since landing and has not recurred. She is unsure if there was any trauma. While the paramedic is establishing IV access and hanging a liter of crystalloid, you perform an ultrasound assessment of the astronaut to further determine the cause of her elevated shock index.
What could be contributing to her vital sign changes?
What SHOCK states are in the differential?
How do the vitals rule-in or rule-out different SHOCK types?
What could be contributing to her knee pain?
RUQ
LUQ
Pelvic
Bilateral anterior lung fields m-mode
Finding in most, but not all, lung fields
Apical 4
PSL
PSS
IVC
What is the differential now based on the US imaging findings?
What is your evaluation of the left heart, the right heart, the lungs, and the IVC?
What are the management considerations in the austere recovery setting?
What is the correct disposition for this patient based on all of her symptoms?
Case 7
Under construction...