CPR.Anaphylaxis.Articles Flashcards
What is BLS goals?
Restore oxygenation, ventilation and blood flow via chest compression and positive pressure ventilation
Describe the assessment of an unresponsive patient
ABC: Airway- open mouth if not responsive sweep.
Breathing- watch for breaths not just agonal
Circulation— pulse assessment high rate of false positives
Unresponsive apneic patients should have CPR initiated
Describe BLS
Chest compressions initiated at 100-120 beats per minute. If airway is obtained positive pressure ventilation at 10 breaths per minute.
If mouth to snout rate of 30 compression to two breaths
What is the cardiac pump theory
Direct compression of the ventricles increases ventricular pressure opening the pulmonic and aortic valves alowing blood flow
Elastic recoil of chest between compressions creates subatmospheric intrathoracic pressure draws venous blood into vessels.
What is the thoracic pump theory
Increase in overall intrathoracic pressure during chest compressions forcing blood from the thorax into the systemic circulation. The heart does not pump rather is it a conduit for flow
What are the correct placement of hands and what theory does it represent in CPR.
Round chest- highest point/ thoracic pump
Keel chest- over heart/ cardiac pump
flat chest- dorsal recumbency/ cardiac
small animal- over heart/ cardiac pump— one hand method
Define ALS
advanced life support: initiate monitoring, vascular access and reversal agents
What are the shockable rhythms in CPR
Ventricular fibrilation and pulseles ventricular tachardia (HR > 200).
Max 10 J/kg
How do you treat refractory VF in CPR
amiodarone 2.5-5 mg/kg IV/IO
Lidocaine if this does not work— sown to increase energy required in shock for monophasic. Does not appear to be an issue with biphasic
Describe how to perform open chest CPR
Patient is in right lateral recumbency for a left lateral thorocatomy. A quick clip of the 3-6th rib spaces and a splash of cholorexadine scrub removed with saline. Sterile gloves
Incision between the 4-5 intercostal space. Finnechito retractors are used to expand space. Incise/remove peridardium. Use two hands to compress apex to base
Describe why bicarb is administered in CPR
In prolonged CPA ( > 10-15 min) Sodium bicarb consided at 1 mEq/Kg once.
Only when a metabolic acidosis < 7.0 is noted. Patient likely to have acidosis with CPA
What are the objectives once ROSC is achieved
Avoid hyperoxemia/hypoxemia SaO2 94-98%, PaO2 80-100 mmHg MAP > 80 mmHg ScvO2 > 70% Lactate < 2.5 mmol/L
What are the 4 areas of Post cardiac arrest syndrome
Systemic ischemia/reprofusion responses
PCA brain injury
PCA myocardial dysfunction
Persitant precipitating pathology
What are the optimization of ischemia/reperfusion injury for ROSC?
Glycemic control- less than 180 mg/dl Worse outcome when higher
CVP >0 <10 mmHg
Steroids if vasopressor dependent shock at hydrocortisone 1 mg/kg IV q 6 hrs
How is the brain exposed to injury with a CPA?
Injury sustained during reperfusion
cytosolic and mitochondrial calcium overload leads to activation of proteases that lead to neuronal cell death and ROS
Burst of ROS occurs during reprofusion, oxidative alterations of lipids, proteins, nucleic acids
Mild theraputic hypothermia decreases cerebral dysfunction
What is therapeutic hypothermia ROSC and when is it considered?
32-34C (89.6-93.2F) for 24-48 hours for dogs that are comatose and need mechanical ventilation.
Rewarm at 0.25C-0.5C per hour
Watch for shivering, increase muscle tone which increases O2 demand.
Decreased brain metabolism therefore it can tolerate longer ischemia— not shown helpful in recent human trials
How long will neurological signs persist post ROSC
Neuro status not good predictor of outcome until 72 hours. EEG can improve this earlier
Should anti-epileptics be initiated post cardiac arrest
Seizures and non convulsive seizrues in people have worse outcomes. Seizures increase O2 demand.
Tx with antiepileptics— pheno, keppra
Increased ICP not common in people but okay to tx with hypertonic agents
What is PCA myocardial dysfunction and how long does it last
Increased CVP and PCWP
Reduced L/R sided systolic diastolic ventricular function with increased end diastolic and systolic volume
Reduced left ventricular ejection fraction and cardiac output
Is hypotension necessary for a diagnosis of shock according the 2007 consensus statement on monitoring shock?
Hypotension is not necessar as is circulatory and cellular dysfnuction.
Markers lactate >2.5 mmol/L and ScvO2 <70%
In JVECC 2016 what were characistics of dogs found to have fluid on AFAST/TFAST in ECC?
More unstable patients had fluid
Free fluid patients had higher lactate
shock index higher in dogs with free fluid
What are the benefits and risks of a inspiratory impedance threshold device?
Device that generates a momentary resistance in inspiration (break) which augments negative intrathoracic pressure and improves venous return.
Good for hemodynamic values, but increases airway resistance and decreases respiratory compliance
Describe how to measure CO by ultrasound velocity dilution
An extracoporeal circuit is created from an arterial cath (metatarsal) to a central venous cath with a pump. Transonic ultrasound velocity tranducers are placed before the venous side and after the arterial side. A known volume of body temp isotonic saline (0.5-2 ml/kg) bolus is given prior to the transducer in the circuit. It senses the velocity change due to dilution.
Compares well to LiDCO even with hypovolemia hemorrhage
Are abdominal compressions recommend in recover guidelines?
Abdominal compressions cause minimal trauma when performed correctly. Improves venous return and should be performed if staffing is available.
How is vasopressin recommended in the recover guidelines
Mediated through V1 in smooth muscle. Receptors are active despite acidemia.
May be used in conjuction with or as subsitute for Epi
0.8U/kg
Describe monophasic vs biphasic defibrillation
Monophasic: one way
Biphasic: initally goes one way then travels back to initial
Compression continue after shock for 2 minute cycle.
In a JVECC 2017 study what was the fastest method for achieving vascular acess
IO was faster for one person in which the jugular IV access was also as fast. Used rotary device in the humerus
In Paramedic 2 was epinephrine a benefit
Epinephrine given out of hospital did improve 30 day survival but did not improve neurological status
In THAPAC was hypothermia a benefit
Hypothermia in childern at 33C for in hospital CPA did not improve functional outcome or survival at 1 year.
In a CCM 2018 study what was noted regarding right ventricular dilation during CPR
Right ventricular dilation as determined via ultrasound during CPR was larger for PE compared to hypoxia or arrhythmia however detection accuracy was not good with users
Define hypersensitivity
reproducible signs that occur with exposure to stimulus at a dose tolerated by normal people.
all encompassing term
Define anaphylaxis
Serious life threatening genralized or systemic hypersensitivity reaction. Generally considered IgE mediated
Describe how anaphylaxis occurs- pathophys
Type 1 immediate reaction.
Mast cell has IgE antibiotidy at the Fc portion will cross link when rexposure occurs.
Mast cell degranulation: Histamine, tryptase, heparin, cytokines
Platelet activating factor leads to bronchoconstriction
What are the common anaphylaxis organs in dogs vs cats
Dogs: Liver GI Hepatic venous congestion leading to necrosis
Cats: Pulmonary and GI Bronchoconstriction, laryngeal edema and mucous production
How do antihistamines and steroids aid in anaphalxitic reactions
Won’t help with cardiovascular but may be helpful with cutaneous signs. Good for mild to moderate, only if ocular/nasal/cutaneous in severe
Steroids not good evidence either way
How does epinephrine help in anaphalcitc reactions
Alpha 1 adrengic stimulation vasoconstriciton on small arterioles (can help with edema)
B2: bronchodilation, decrease histamine release
B1: increase cardiac contractility
0.01 mg/kg IM Max 0.3 mg
What are the three types of anaphylactic reactions
Immunologic IgE
Immunologic non IgE
Non- Immunologic
How to treat anaphylaxis refractory to epinephrine
Vasopressors: Dopamine, norepi, vasopression
Glucagon- may help with patients on a beta blocker. can cause emesis, protect airway. Bolus then CRI
Atropine- for resitant bradycardia
Ipratropium inhaled for resistant bronchospasms
