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Flashcards in Pericardial diseases Deck (29)
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1

The pericardial cavity normally holds _______ ml

with a chronic pericardial effusion, the pericarial cavity can have as much as ________ mLs of fluid without sidnificant increases in pressure

however with an acute pericardial effusion __________  will cause ____________

The pericardial cavity normally holds _______ ml

with a chronic pericardial effusion, the pericarial cavity can have as much as ________ mLs of fluid without sidnificant increases in pressure

however with an acute pericardial effusion __________  will cause ____________

  1. 20-50 mL
  2. 1000 mL (1L)
  3. even small voumes (100-200 mL) that accumualte rapidly
  4. an increase in cardiac pressure and cardiac tamponade

2

what 2 features distinguish acute pericarditis from anginal pain?

  1. the pain gets worse with INSPIRATION or laying down (recumbancy)
  2. EKG shows diffuse ST and T wave changes (In all leads?). 

(another diagnostic criteria is the presesnce of a friction rub)

3

What is the typical pericardial pressure

  • Similar to pleural pressure it varies with respirations between -4 and +4mmHg

4

Function of the pericardium

  1. Lubricates the heart
  2. Facilitates motion within the sac  
  3. Protects the heart from excessive displacement
  4. Maintains optimum shape of the heart
  5. Applies compensatory hydrostatic pressure to the heart to compensate for alterations in gravitational force

5

Bonus- Whats the IV dosing for midazolam? Oral?

IV premedication: 1-2.5mg (max 5mg) 

Inucion agent: 0.1-0.2 mg/kg 

Oral premed:  0.5mg/kg (max 20mg) 

6

What is the pericardium

  • Sac surrounding the heart,
  • composed of two layers
    • Visceral- thin, tissue like
    • Parietal- more rigid, fibrous layer

7

What are the three most frequent responses to pericardial injury?

  1. Acute Pericardidis
  2. Pericardial Effusion
  3. Constrictive Pericarditis

8

Bonus- What's the dosing for ketamine?

What is ketamine's protein binding?

  1. Induction: 0.5-2 mg/kg IV
  2. sedation: 0.2-0.5 mg/kg IV 
  3. maintenance: 1-2 mg/kg/hr IV
  4. IM/PR: 5-10 mg/kg  
  5. 12% protein bound, (low compared to the other induction agents)

9

Acute pericarditis →what causes it , what is  the treatment?

  1.  Often caused by: virus, infections, MI, trauma, cancer, drugs ( immunosupressants), systemic diseases RA, SLE,
  2. Often labeled acute BENIGN pericarditis→usually unaccompanied by a pericardial effusion or tamponade and RARELY progressive to restrictive pericarditis
  3. Treatment
    1. Salicylates/NSAIDS
    2. Analgesics (Indomethicin-blocks prostaglandins)
    3. Corticosteroids

10

T/F Acute pericarditis always alters cardiac function

False 

Only in the presence of effusion is cardiac function altered

11

What is pericardial effusion? what are the signs/symptoms?

  1. Accumulation of fluid in the pericardial cavity, (idiopathic or neoplastic origin)  
  2. Rate of fluid accumulation determines symptoms
    1. Acute:
      • pericardiaum lacks time to adapt
      • intrapericardial pressures increase rapidly 
      • 100-200 mL of fluid can cause tamonade 
    2. Chronic/gradual:
      • pericardiaum can stretch to acomidate fluid
      • up to 1000 mL can accumulate without a change in pressure

​​(ECHO is very accurate on measuring the size of the effusion)

12

Why is there a rapid rise in CVP with cardiac tamponade? 

As pericardial pressures increase the right atrial pressure will increase in parallel

so the right atrial pressure is a REFLECTION of the intrapericardial pressure

when CVP starts to change signs and symptoms of cardiac tamonade develop 

13

In chronic pericardial effusion how much fluid can accumulate before symptoms are noticed

Up to 1000ml

the slow rate of accumulation allows for the pericardium to stretch without a significant rise in pressure

14

What is the most useful method for detecting and estimating the size of pericardial effusion

ECHO

15

What is impaired in cardiac tamponade

Diastolic filling→ Filling is related to transmural pressure across the chamber, so even a small rise in pressure can impair diastolic filling (low pressure chamber)

16

How can transmural pressure be calculated

Transmural pressure = Chamber pressure - extracavity pericardial pressure

17

Cardiac tamponade s/s

  1. Becks triad - 75% oof acute tamponade exibit 
    1. ​Distant muffled heart sounds
    2. Juggular Venous Distention
    3. Hypotension
  2. ​​​Equilization of Cardiac filling pressures
  3. Narrow pulse pressures
  4. decreased CO and SV will activate the SNS leading to tachycardia
  5. Increased cetral venous pressure→reflection of increased transmural pressure and resistance to atrial filling
  6. Decreased voltage on EKG → ​Accumulation of fluid
  7. Pulsus paradoxus
    • >10mmHg drop in SBP during inspiration
    • pulse wave amplitude on A-line will also decrease 
  8. Tachypnea→ less room for expanionin the thoracic cavity 

18

Definitive treatment treatment for cardiac tamponade

  1. Pericardiocentesis
  2. Subxiphoid pericardiostomy
  3. Thoracic pericardiostomy

19

Anesthetic management for cardiac tamponade

Must manage until definitive treatment can be done!!!!

GOAL = maintinence of adequate CO and BP

  1. Give fluids to expand volume
  2. Increase contractility (Isoproterenol)
  3. Correct acidosis (this will increase BP and HR)

20

Bonus- What are the basic pharmacokinetics for propofol

  • Onset: 30 sec
  • DOA: short- redistributes in 2-8 min for wakeup
  • Vd- 3.5-4.5 L/kg
  • E1/2- 0.5-1.5 hrs

21

Constrictive pericarditis patho

Scarring/adhesions of the pericardium leads to a rigid, stiff shell around the heart

Impairs diastolic filling (heart cannot relax)

Can be caused by previous cardiac surg, radiation, TB.

Also often idiopathic.

22

Constrictive pericarditis s/s

Similar to Tamponade - JVD may be more prevalent and less likely to see pulsus paradoxus with constrictive pericardiditis

  1. Incerased CVP, RAP, PCWP
  2. decreased CO  
  3. Fatigue
  4. Atrial dysrhythmias (a-fib/a-flutter) 
  5. Edema
  6. Ascites  and Hepatomegaly

(there is often ventricular disonence with both tamonade and constrictive pericardidit - I think this is a 3rd degree block)

23

Tx for constrictive pericarditis

Pericardiectomy- removal of adherent/fibrous pericardium 

  • often high blood loss
  • cardiac dysrhythmias in theis surgery ususally due to mechaneical compression of the heart

24

Bonus- What are the pKas for Lidocaine, Bupivacaine, and Chloroprocaine?

  • Lidocaine 7.9
  • Bupivacaine 8.1
  • Chloroprocaine 8.7 (but still fast onset time...)

(The Closer to 7.4 the faster the onset in general)

25

Explain Acute pericardiditis after an MI

  1. Occurs in 10-15% of patients
  2. Usually develops 1-3 days post MI
  3. It is usaually due to a transmural MI- it is a result of  an interaction between healing necrotic myocardial tissue with the pericardium

26

Definition of Cardiac Tamponade

  1. Can occur any time fluid collects in the pericardial sac and is under pressure
  2. Tamponade exists when there is an increase in pressure that IMPAIRS diasolic filling of the heart
    1. Increased CVP

27

Drugs to use and avoid in a patient getting a pericardiocentesis. Why?

  1. Use: Ketamine - wnat to maintain SNS outflow!!!
    1. also can do under local
    2. can induce with benzos, fentanyl, nitrous oxide - (if an exploration is being done prep patient with drapes prior to induction and keep sitting upuntil ready to start!)
    3. Pancuronium = stimulates ganglion→good to keep HR up
  2. DO NOT USE: Propofol!!!!!
  3. Want to avoid GA and positive pressure ventilation becasue it can casue life threatening hypotension

28

What should be anticipated once the couse of cardiac tamponade is releived? 

  1. Expect a significant swing in BP from hypotensive to hypertensive 
  2. Must be prepared to treat - especially if the cause of tamonade is due to aortic hematoma, aortic disection or aneurism

29

Anesthetic Management for Constrictive pericarditis

Minimize Changes! To everything! 

  • Maintain HR, Preload SVR and contractility
  • Usually getting a pericardiectomy - removal of adherent pericardium
    • Often high blood loss 
    • Maintain volume with fluid and replace blood loss!!! 
    • Have blood ready
  • AVOID bradycardia - CO dependent on HR
  • They will tolerate a moderate increase in HR 
  • Drugs that can be used
    • ketamine
    • etomidate
    • pancuronium
    • sympathomimetics
  • Intraop cardiac arrythmias are usually from mechanical compression of the heart
  • Large-bore IVs, CVP, A-line