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Cardiac dysrhythmias & arrest R1 1. Signs & symptoms of
cardiac arrest(1) agitation, disorientation, anxiety R/o: hypoxia,
acidosis or hypoglycemia(2) changes in respiratory pattern, efforts
or sounds(3) changes in heart rhythm, BP, pulse pressure, venous
distension, capillary refill or skin color, temperature or
moisture
Cardiac arrest is recognized clinically by(1) cessation of
respiration(2) loss of palpable pulse(3) cessation of bleedingII.
Etiology of cardiac arrest & dysrhythmias respiratory arrest
syndromes(1) obstructed airway d/t foreign body or tongue(2)
cessation of effective mechanical breathing : head trauma, CVA,
pneumothorax, massive hemothorax(3) toxins preventing effective
uptake or delivery of O2: CO, G(-) sepsis(4) severe intrapulmonary
shunt3II. Etiology of cardiac arrest & dysrhythmias Other
cardiac arrest sydrome(1) hypovolemic shock(2) septic shock(3)
cardiogenic shock(4) severe respiratory acidosis(5) myocardial
infarction(6) primary dysrhythmias from intrinsic cardiac Ds(7)
severe electrolyte abnormalities(8) severe metabolic acidosis
secondary to renal failure, DM(9) hypothermia secondary to eg: adm
of cold blood(10) drug overdosage or toxicity to cardiac or
antidepressant medication
: all of the shock syndromes, including hypovolemic shock,
result in the following functional derangementsIII. Therapy or Tx
-> CPRArrest rhythm recognition & therapy: clinical Dx of
one of the cardiac arrest rhythms must be made as soon as
possible
(1) ventricular fibrillation (VF) is caused by excessive
irritability of myocardium secondary to hypoxia, acidosis or
etc.(2) ventricular tachycardia (VT) is also.(3) electromechanical
dissociation (EMD) is diagnosed after rhythmic electrical activity
of heart is present without peripheral pulses or BP(4) Asystole
(ASYT) carries an extremely poor Px. no matter what its
etiologyDysrhythmia recognition & therapyGeneral comments1.
dysrhythmia can be grouped into 3 categories(1) causing immediate
hemodynamic deterioration: severe tachyarrhythmias, severe
bradyarrhythmias(2) without immediate hemodynamic consequence but
presaging more ominous dysrhythmias(3) benign dysrhythmias
requiring no specific therapy
2. General approach to treatment may include(1) support of vital
functions (respiration, circulation)(2) identification of
dysrhythmia & reversal of the cause(3) Pharmacologic therapy
specific to dysrhythmia or hemodynamic disturbance(4)
Cardioversion: difibrillation or pacemaker placementIV.
BradycardiaDefinition(1) rate < 50(2) rate < 60 with systolic
BP < 90(3) premature ventricular contractions: PVCs
Tx(1) atropine 0.5mg IV, repeated every 5 min up to 2.0mg
total(2) isoproterenol infusion, 2-20 g/min, if (1) unsuccessful(3)
pacemaker(4) If rate increased * is > 60 ; BP > 90 ->
obsevation (pacemaker may still be required)
BP < 90 -> assess for hypovolemia fluid change with
vasopressors 10-20ml/kg
