Shock

Question 1

What is shock?

Answer 1

Broad term that describes a physiologic state where oxygen delivery to the tissues is inadequate to meet metabolic requirements, causing global hypoperfusion. It may also be thought of as an imbalance between tissue oxygen supply and demand.

Question 2

What is the difference b/w compensated and uncompensated shock?

Answer 2

• Compensated: normal BP with inadequate perfusion

- Uncompensated: hypotension and inability to maintain normal perfusion

Question 3

What are some types of distributive shock?

Answer 3

Sepsis, anaphylaxis, neurogenic

Question 4

What are some types of obstructive shock?

Answer 4

(non-cardiac obstruction)

PE, tension PTX, tamponade

Question 5

*How is the shock index calculated?

What’s a nl range?

Answer 5

HR / sBP

0.5-0.7

Question 6

Repeated shock index values >___ indicate decreased left ventricular function and are associated with higher mortality.

Answer 6

1.0

Question 7

How do the following change in cardiogenic shock?

• HR
• CVP
• Contractility
• SVR

Answer 7

• HR: ^
• CVP: ^
• *Contractility: vv
• SVR: ^

Question 8

How do the following change in hypovolemic shock?

• HR
• CVP
• Contractility
• SVR

Answer 8

• HR: ^
• *CVP: vv
• Contractility: +/- ^
• SVR: ^

Question 9

How do the following change in distributive shock?

• HR
• CVP
• Contractility
• SVR

Answer 9

• HR: ^
• CVP: vv
• Contractility: +/-
• SVR: v

Question 10

How do the following change in obstructive shock?

• HR
• CVP
• Contractility
• SVR

Answer 10

• HR: ^
• CVP: +/- ^
• Contractility: +/-
• SVR: ^ (tamponade, PE) or v (tension PTX)

Question 11

Besides elevated lactate, what other lab suggests a shift to anaerobic metabolism and tissue hypoperfusion?

Answer 11

Decreased serum bicarbonate

Question 12

What are some lab/radiology signs of end-organ damage in shock?

Answer 12

• elevated creatinine
• abnormal liver function tests
• ARDS/edema on chest x-ray
• arrhythmia/ischemia on EKG
• abnormal cardiac enzymes
• ischemic neurologic changes on CT/MRI

Question 13

Proper oxygenation is critical in shock tx. Target central venous oxygenation levels above ___%.

Answer 13

70%

Question 14

*Why might you start a central venous catheter in shock tx?

Answer 14

Can help for rapid fluid and medication delivery, as well as provide invasive monitoring

Question 15

*In the cardiogenic shock pt with pulmonary edema, in initial resuscitation, what must you be careful about? (1)

Answer 15

Giving fluids

Question 16

In the shock pt, if volume resuscitation does not improve the patient’s hemodynamic status, what types of medications can you resort to?

Answer 16

Vasoactive medications:

• epinephrine
• norepinephrine
• dopamine
• vasopressin

Question 17

What are invasive ways to monitor fluid status during shock besides a central venous catheter?

Answer 17

• Urinary catheter

- Intra-arterial BP measurements

Question 18

How does an intra-aortic balloon pump work?

Answer 18

• Inflate in diastole, improved venous return to the cardiac muscle
• Deflates in systole, decreasing afterload
• Combined, v myocardial O2 demand and ^ O2 supply

Question 19

Resuscitation of a shock state is thought to be successful when the following occurs: (5)
- *lactate decreases by ______ in the first couple of hours

Answer 19

• normalization of hemodynamic state (BP, HR, and urine output)
• *lactate decreases by half in the first couple of hours
• normal volume status restored
• maximal tissue oxygenation
• resolution of acidosis and return to normal metabolic parameters

Question 20

What is the usual dispo of the shock pt?

Answer 20

ICU

Question 21

Despite proper treatment, the mortality rates from shock can exceed ___%.

Answer 21

50%

Question 22

True or false: SIRS criteria have poor sensitivity and specificity for sepsis.

Answer 22

True

Question 23

*Define SIRS criteria

Answer 23

1. Temp > 38°C (100.4°F) or < 36°C (96.8°F)
2. HR > 90
3. RR > 20 or PaCO2 < 32 mmHg
4. Abnormal WBC: >12,000/µL or < 4,000/µL or >10 bands

Question 24

*Define sepsis crteria

Answer 24

2/4 SIRS + signs of infection

Question 25

*Define severe sepsis

Answer 25

Sepsis-induced tissue hypoperfusion | - Elevated lactate (>4) or new organ dysfunction

Question 26

*Define septic shock

Answer 26

Sepsis-induced hypotension persisting even with fluid resuscitation (*SBP < 90, MAP < 65, or SBP < 40 from baseline) - Would also therefore meet criterial for severe sepsis

Question 27

Review some end-organ signs of severe sepsis.

Answer 27

- (SBP)<90 mm Hg or mean arterial pressure <70 mm Hg or a SBP decrease >40 mm Hg or <2 SD below normal for age or known baseline - Creatinine > 2.0 mg/dl (176.8 mmol/L) or Urine Output < 0.5 ml/kg/hour for > 2 hours, - Bilirubin > 2 mg/dl - Platelet count < 100,000, - Coagulopathy (INR >1.5 or aPTT >60 secs), - Lactate > 2 mmol/L (18.0 mg/dl) - Urine output < 0.5 ml/kg/hour

Question 28

*What is the agreed upon adequate amount of fluid resuscitation before diagnosing septic shock?

Answer 28

30 mL/kg

Question 29

____________ is the primary method of risk stratification for patients presenting with sepsis.

Answer 29

Lactate | - Correlates with mortality

Question 30

In sepsis, should abx be initiated before testing at all times?

Answer 30

Not necessarily (studies show it might not matter up to 5 hrs later, so can get studies first to find source often)

Question 31

*What is involved in early goal directed therapy (EGDT) for sepsis tx?

Answer 31

This involved: - placement of an arterial line and central venous catheter (CVC), - titration of IV fluids to achieve a central venous pressure between 8-12 mm Hg, - titration of vasopressors to achieve a MAP greater than 65 (monitor w/A-line), and - measurements of central venous oxygen saturation. When low, blood transfusions and dobutamine were administered to raise this level.

Question 32

What parts of the early goal directed therapy for sepsis protocol might not be needed?

Answer 32

CVC and Scvo2 monitoring for most patients.

Question 33

**In the sepsis SEP-1 criteria, what is in the 3-hour bundle? *In the sepsis SEP-1 criteria, what is in the 6-hour bundle?

Answer 33

- Lactate - BCx before abx administration - Abx - 30 ml/kg IV crystalloid for hypotension or lactate ≥ 4 mmol/L. (use caution in patients with ESRD, CHF, and ESLiverD) - Vasopressors for hypotension -> MAP ≥ 65 mmHg - Reassess and document volume status after fluids for patients with hypotension that does not respond to fluids or lactate ≥ 4 mmol/L - Repeat lactate if initial was ≥ 4 mmol/L

Question 34

In sepsis, must reassess patients frequently because often patients may become hypotensive __-__ minutes after antibiotic administration.

Answer 34

30-60 min