WEEK THREE

Question 1

What do you need to assess and monitor in cardiac?

Answer 1

Preload
Contractility
After load
Stroke volume
Cardiac Output (CO)
Central Venous Pressure (CVP)
Mean arterial pressure (MAP)

Question 2

What is Preload?

Answer 2

Pressure or stretch exerted on the walls of the ventricle by the volume of blood filling the ventricles at the end of diastole

Question 3

What is Contractility?

Answer 3

The ability of a muscle to shorten when stimulated; in particular the force of myocardial contraction

Question 4

What is Afterload?

Answer 4

The resistance to ventricular contraction; pressure the ventricles have to overcome to eject blood into the circulation

Question 5

What is Stroke Volume?

Answer 5

Volume of blood pumped with each heart beat. 50-100mL/beat

Question 6

What is Cardiac Output (CO)?

Answer 6

The amount of blood pumped by the heart each minute

SV X HR = CO

Question 7

What is Central Venous Pressure (CVP)?

Answer 7

Preload of the right ventricle measured by the CVP

Question 8

What is Mean Arterial Pressure (MAP)?

Answer 8

Average pressure within the aterial system throughout the cardiac cycle 70-90 mmHg

Question 9

Cardiac Output features:

Answer 9

-CO regulated by homeostatic mechanisms
-Regulated in response to stress/disease
-Factors affecting CO
Preload
Afterload
Contractility
-Critically ill patients cannot compensate as well as healthy individuals
-May be unable to >HR to compensate

Question 10

Preload reduction is related to?

Answer 10

• Volume loss (eg haemorrhage)
• Venous dilation – hyperthermia/medication
• Tachycardias – AF/SVT
• Raised intrathoracic pressure (NIV)
• Raised intracardiac pressure – Tamponade
• Body Position can affect preload due to affect on venous return

Question 11

Increased Afterload is related to?

Answer 11

• Increased ventricular radius
• Increased aortic impedance
• Raised intra cavity pressure
• Negative intrathoracic pressure
• Increased systemic vascular resistance

Question 12

Contractility is decreased by?

Answer 12

Hypoxia
Ischemia
Drugs ie thiopentone, calcium channel blockers

Question 13

Increasing Contractility will?

Answer 13

Increase myocardial oxygen demand

Question 14

Assessment of Cardiac Output?

Answer 14

Establish Diagnosis, determine therapy and monitor response to therapy
Heart rate and rhythm:
-Continuous cardiac monitoring 4 or 5 lead
-12 lead ECG
Hemodynamic monitoring:
-Non invasive, (TPR&BP, oximetry, UO).
-Invasive intra arterial pressure monitoring
-Invasive CVP
-Pulmonary artery pressure (PAP)
-Cardiac output (CO) thermodilution (measures temperature change)

Question 15

12 Lead ECG:

Answer 15

• Essential in critically ill patients even if they have no cardiac symptoms
• All patients who have a cardiac event must have an -ECG ASAP
• Diagnosis can be made rapidly
• Treatment can commence
• Earlier treatment can lead to better prognosis

Question 16

Pulmonary Artery Catheter?

Answer 16

• Pulmonary artery pressure and wedge waveforms.
• Filling pressure of the right ventricle (right ventricular preload) is measured through the pulmonary catheter port opening into the:
  1. Superior vena cava
  2. Right atrium
  3. Right ventricle
  4. Pulmonary artery

Question 17

Non invasive Assessment?

Answer 17

Visual observation of patient
Pulses
Pulses on monitors do not tell the whole story
Touch your patient
Check pulse for:
-Rate, rhythm, and strength
Pulses to check:
-Radial
-Carotid
-Femoral

Question 18

How to calculate rate:

Answer 18

A) Count the number of large boxes between 2 R waves

B) Divide 300 by the number of the large squares, this is your approximate rate.

Question 19

Mophine:

Answer 19

-Analgesia
-Opium – binds to receptors in brain, spinal cord and other tissues
-Primary effects on CNS and other smooth muscle
-Peak analgesia 30 – 60 minutes
-Contraindications:
Previous sensitivity, Opioid sensitivity, Bronchial asthma/COPD
-Reactions:
Sedation, Nausea, Vomiting, Constipation, Blurred vision, Local issue irritation (at site of injection)
-Dosage:
Adults – 5 - 20mg every 4 – 6 hourly max , Children – 0.1 to 0.2 mg/kg bodyweight Max 15mgs
-Overdose:
ABC, Oxygen, Naloxone 0.4 to 2 mg intravenously every 2 to 3 minutes as necessary, ?IM Naloxone to support respiratory function

Question 20

Metoclopromide :

Answer 20

-Anti emetic
-Accelerates gastric emptying, increases peristalsis
-Acts in 1-3 minutes IV, 10 – 15 mins IM
-Should not be used in patients with prolonged QT – can cause Torsades de Pointes
-Contraindications:
GI Haemorrhage, Obstruction, Perforation, Epilepsy, Extrapyramidal reaction, Oculogyric crisis – Treat with procyclidine
-Reactions:
Headache, Drowsiness, Fatigue
-Dosage:
10mg IMI TDS Slow (1-2 Mins), Children 1-10mg depending on Age