Mod12: Treatment of Anaphylaxis DuringAnesthesia

Question 1

_{Treatment of Anaphylaxis During Anesthesia}

What does Primary treatment starts with?

Answer 1

Stop antigen administration

Question 2

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

After stopping administration of the antigen, what must you do next in a patient with no advanced airway?

Answer 2

Maintain airway via preemptive instrumentation, and

Administer 100% oxygen to correct V/Q mismatch if suspected and prevent ischemia

Question 3

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

True or False: during an anaphylaxis, it is appropriate to discontinue all anesthetic agents and wake the pt up if the surgical procedure allows it.

Answer 3

True

If the surgical procedure does not allow it, communicate with the surgeon to possibly shorten the procedure and complete it at a later time

Question 4

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

Why would you consider additional IV access and arterial line as part of the primary treatment of anaphylaxis?

Answer 4

Volume expansion for hypotension

Strict BP monitoring

Question 5

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

What’s the first Tx for hypontension during anaplylaxis?

Answer 5

Volume expansion

Question 6

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

Why is volume expansion the first Tx for hypontension during anaplylaxis?

Answer 6

Up to 40 percent loss of intravascular fluid into the interstitial space d/t increased capillary permeability

Question 7

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

Which solutions would you use for volume expansion in the Tx of hypontension during anaplylaxis?

Answer 7

25-50 ml/kg of

Lactated Ringer’s solution - Normal saline

^{(75% will move into the intertitial space after 30 min),}

or

Colloid solutions

^{(beneficial d/t higher oncotic pressure)}

Question 8

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

How would you treat persistent hypotension resistant to initial volume expansion during anaphylaxis?

Answer 8

Additional volume

Question 9

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

What are the three different ways Epinephrine is helpful in the Tx of anaphylaxis?

Answer 9

Inhibits mediator (histamine) release by increasing cyclic AMP in mast cells and basophils

(This stabilizes the cells and prevents degranulation)

Alpha1 effects to reverse hypotension

Beta2 effects for bronchodilation

Question 10

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

A benefit of Epinephrine is that it has a rapid onset when given IV, but why are repeated doses necessary?

Answer 10

It has short duration

Question 11

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

How much Epi would you give to treat hypotension a/w anaphylaxis?

Answer 11

5 - 10 mcg IV

Titrated doses for hypotension

Question 12

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

How much Epi should you give to treat cardiovascular collapse a/w anaphylaxis?

Answer 12

0.1 - 1mg IV

Titrated doses for cardiovascular collapse

^{(Higher doses may be required for CV collapse - May also consider a continuous infusion)}

Question 13

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

Epinephrine is available in a very concentrated form. What is crucial that you do properly prior to administration?

Answer 13

Dilute it down appropriately to avoid administration of a massive dose

Question 14

_{Treatment of Anaphylaxis During Anesthesia - Primary treatment}

How could you administer Epi to treat anaphylaxis in patients with laryngeal edema without hypotension?

Answer 14

Subcutaneous

Question 15

_{Treatment of Anaphylaxis During Anesthesia - Hypersensitive to Epinephrine}

Patients taking which drugs may be hypersensitive to Epinephrine?

Answer 15

Tricyclic antidepressants

MAO inhibitors

Cocaine or other stimulants

(Concomitant administration of Epi to these pts may exhacerbate tachycardia and result in cardiac ischemia)

Question 16

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

How much of which H1 receptor antagonist drug should you administer as secondary treatment in the Tx of anaphylaxis?

Answer 16

Benadryl 25 to 50 mg IV (up to 1.0 mg/kg)

Question 17

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

How does Benadryl attenuate systemic effects in chemically mediated reactions responsible for anaphylaxis?

Answer 17

Via H1 and H2 receptors antagonism

Question 18

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

True or False: Antihistamines inhibit histamine release

Answer 18

False

Antihistamines compete with histamine at receptor sites but do not inhibit histamine release

Question 19

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

True or False: Benadryl (diphenhydramine), an H1 antagonist, blocks both H1 and H2 receptors

Answer 19

False

H1 antagonists do not block H2 receptors

Question 20

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

True or False: Tagamet (cimetidine), Zantac (ranitidine), and Pepcid (famotidine), H2 antagonists, blocks both H1 and H2 receptors

Answer 20

False

H2 antagonists do not block H1 receptors

Question 21

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

What are recommended doses for H2 antagonits?

Answer 21

Tagamet (cimetidine) 400 mg IV

Zantac (ranitidine) 150 mg IV

Pepcid (famotidine) 20 mg IV**

^{(** most commnonly given in the OR)}

Question 22

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

Why are Corticosteroids (0.25-1.0g hydrocortisone) beneficial in the Tx of anaphylaxis?

Answer 22

May alter the activation of other inflammatory cells following an acute reaction

Question 23

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

Corticosteroids onset is 12 to 24 hours later. Why give then during an acute reaction?

Answer 23

May attenuate recurring or late-phase reactions

Useful in refractory bronchospasm or shock

Question 24

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment}

Which corticosteroid is particularly useful in protamine reactions?

Answer 24

1 to 2 g of methylprednisolone (30 to 35 mg/kg)

Question 25

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} Which drug will you administer to treat Bronchospasm refractory to epinephrine?

Answer 25

Inhaled **ß2-adrenergic** agents | (albuterol or terbutaline)

Question 26

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} How much and via which route will you administer inhaled ß2-adrenergic agents (albuterol or terbutaline) to treat Bronchospasm refractory to epinephrine?

Answer 26

**4 to 12 metered dose** inhaler puffs via **ETT** Give at **inspiration** Effectiveness manifest as _drop in peak airway pressure_ and _increased tV_ **Repeat** if not improving or wrsening PIP and tV

Question 27

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} How much of nebulized albuterol will you administer to treat Bronchospasm refractory to epinephrine?

Answer 27

0.25 to 1mL of albuterol in 2.5mL of normal saline

Question 28

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} When would consider a Catecholamine infusion?

Answer 28

Persistent hypotension or bronchospasm

Question 29

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} At what rate would you administer an Epinephrine infusion?

Answer 29

4-8 mcg/min

Question 30

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} At what rate would you administer an Norepinephrine infusion?

Answer 30

4-8 mcg/min

Question 31

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} When is Norepinephrine infusion indicated?

Answer 31

Norepinephrine decreases cyclic AMP Use only in patients with refractory hypotension due to decreased systemic vascular resistance

Question 32

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} Which Catecholamine infusion is indicated when ß1, ß2 selective properties that produce tachy dysrhythmias\* (sometimes needed in EP to localize and ablate dysrhythmias) and systemic vasodilatation are needed?

Answer 32

**Isoproterenol** 0.5-1.0 mcg/min

Question 33

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} In which conditions is Isoproterenol indicated?

Answer 33

_{Used in patients with:} **Refractory bronchospasm** **Pulmonary hypertension** or **Right ventricular dysfunction**

Question 34

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} Why should Isoproterenol be used cautiously in hypotensive or hypovolemic patients?

Answer 34

Profound **ß2 effects** can produce systemic **vasodilatation**

Question 35

_{Treatment of Anaphylaxis During Anesthesia - Catecholamine infusions} Depending on treatment objectives, which other Catecholamine infusions could be used in the Tx of anaphylaxis?

Answer 35

**Dopamine** 3-20 mcg/kg/min **Dobutamine** 5-20 mcg/kg/min

Question 36

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} What are appropriate interventions to increase the effectiveness of Epinephrine in the context of refractory hypotension or acidemia?

Answer 36

Monitor ABGs Treat acidemia with **Sodium bicarbonate** 0.5 to 1 mEq/kg Reduced acidemia improves effectiveness of Epi

Question 37

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} When would you use Phosphodiesterase Inhibitors to treat bronchospasm?

Answer 37

In **refractory bronchospasm**, not aleviated by drugs used for primary treatment and **hemodynamic stability**

Question 38

_{Treatment of Anaphylaxis During Anesthesia - Secondary Treatment} Which Phosphodiesterase Inhibitor would you use to treat refractory bronchospasm during anaphylaxis? and how much?

Answer 38

**Aminophylline** Loading dose of 5 to 6 mg/kg given over 20 minutes Followed by an infusion of 0.5-0.9 mg/kg/hr

Question 39

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} Which pressor would be indicated for the Tx of hypotension that is refractory to epinephrine and volume replacement?

Answer 39

**Vasopressin** 2 – 5 units

Question 40

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} Pts taking which drugs chronically are at risk for hypotension that is refractory to epinephrine and volume replacement?

Answer 40

Patients on **alpha** or **beta blockers**

Question 41

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} What are the beneficial effects of Glucagon (1 mg IV) in the treament of hypotension that is refractory to epinephrine and volume replacement?

Answer 41

**Polypeptide hormone** with potent _chronotropic_ and _inotropic_ effects (**increases cAMP**)

Question 42

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} If required, what would be the rate of Glucagon continuous infusion?

Answer 42

**1 to 5** mg/hr

Question 43

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} Which lab value should be monitored during a Glucagon continuous infusion?

Answer 43

Blood glucose To prevent Hyperglycemia

Question 44

_{Tx of Anaphylaxis - Refractory cases not responding to Epi and volume} Which drug is inticated in the Tx of refractory hypotension not responding to Epi and volume in patients receiving ACE inhibitors chronically?

Answer 44

**Angiotensinamide**

Question 45

_{Treatment of Anaphylaxis During Anesthesia} What should you consider before removing an ETT from these pts?

Answer 45

Evaluation of airway Extent of laryngeal edema

Question 46

_{Treatment of Anaphylaxis During Anesthesia} How would you manage a pt with persistent facial edema after an anaphylactic reaction?

Answer 46

Delay extubation May continue for 24 hours (Keep intubated for at least 24hrs)

Question 47

_{Treatment of Anaphylaxis During Anesthesia} How would you evaluate extent of airway edema prior to extubation?

Answer 47

Persistent **facial edema** suggests airway edema **Deflate ET tube cuff** and listen for **leak** around it. Ensure there is a significant air leak after endotracheal tube cuff deflation _before extubation_ ***Direct laryngoscopy** may be performed before extubation of the trachea to visually inspect laryngeal structures​* *(This is not common practice!!!)*

Question 48

_{Treatment of Anaphylaxis During Anesthesia} Why is Direct laryngoscopy not common practice when laryngeal edema is suspected following an anaphylactic reaction?

Answer 48

it requires **resedating** and **reparalyzing** the pt

Question 49

_{Treatment of Anaphylaxis During Anesthesia} What should you do next if you have strong suspicion of laryngeal edema as evidenced by facial edema and absence of leak around deflated ET tube cuff? A. Perform a DL to visually inspect laryngeal structure B. Transfer the patient to the ICU for 24 hr monitoring

Answer 49

A. Perform a DL to visually inspect laryngeal structure ## Footnote **B. Transfer the patient to the ICU for 24 hr monitoring**

Question 50

_{Treatment of Anaphylaxis During Anesthesia - Pts under general anesthesia} Why are sympathetic responses altered during anaphylaxis for patients under general anesthesia?

Answer 50

Inhalational anesthetics

Question 51

_{Treatment of Anaphylaxis During Anesthesia - Pts under general anesthesia} How do inhalational anesthetics alter sympathetic responses during anaphylaxis in patients under general anesthesia?

Answer 51

Interfere with compensatory response to shock and cardiovascular dysfunction

Question 52

_{Treatment of Anaphylaxis During Anesthesia - Pts under general anesthesia} Why are inhalation anesthetics not the bronchodilators of choice in treating bronchospasm following anaphylaxis, especially during hypotension

Answer 52

Because of the **significant hypotension** in anaphylaxis

Question 53

_{Treatment of Anaphylaxis During Anesthesia} Why would Patients under spinal or epidural anesthesia require a larger dose of catecholamine during anaphylaxis?

Answer 53

Because they have already received a **partial sympathectomy** via spinal or epidural anesthesia

Question 54

_{Treatment of Anaphylaxis During Anesthesia} Why is early recognition and early treatment with administration of medications of the utmost importance in anaphylaxis?

Answer 54

Patients who do not appear to have life threatening symptoms on initial presentation may progress to **life threatening anaphylaxis** **Early recognition** of anaphylaxis has a huge effect on **mortality** and **morbidity** The **transition** from initial minor symptoms to life-threatening symptoms can happen rather **quickly**

Question 55

_{Treatment of Anaphylaxis During Anesthesia} Most drugs used to treat the acute symptoms of anaphylaxis are short-acting. Why would you consider adding longer-acting drugs after resolution of the initial treatment phase?

Answer 55

Because of the risk of **Biphasic anaphylaxis** Some patients have a late or second phase of anaphylaxis, even after complete resolution of the first response This is why patients who receive epinephrine for the treatment of anaphylaxis may not improve sufficiently or may improve and then relapse Consider longer-acting drugs such as: **Hydrocortisone** 250 mg IV (prevents delayed release of inflammatory compounds - does not produce an immediate effect)

Question 56

_{Treatment of Anaphylaxis During Anesthesia} What could you do to guard againts Biphasic anaphylaxis?

Answer 56

Supplement emergency short acting drugs with **Continuous infusions**, or **Longer acting drugs (???)**

Question 57

_{Treatment of Anaphylaxis During Anesthesia - Being prepared} How could you prepare and guard againts anaphylaxis?

Answer 57

**Identify** those at risk Training in **recognition** ^{(make it part of your differential diagnosis)} Be familiar with **Posters** _in operating room_ ^{(May provide guidelines in treatment, and guidelines for investigation)} **Drugs** for the immediate treatment of an anaphylactic reaction should always easily be available ^{(Epi must always be present in the anesthesia cart, and you must know how to dilute it down)} Kits for **blood sampling** must be readily available

Question 58

_{Treatment of Anaphylaxis During Anesthesia - Informing the patient} Why should you inform a patient that had recovered from anaphylaxis about what happened?

Answer 58

So that they aware of which drug or substance they are allergic to, along with the associated allergic response

Question 59

_{Treatment of Anaphylaxis During Anesthesia} How and when should you document an anaphylactic reaction

Answer 59

Document details in anesthetic record As soon as possible

Question 60

_{Treatment of Anaphylaxis During Anesthesia} Why should the patient be referred to an allergist familiar with testing for anesthesia agents

Answer 60

So they can be tested for other allergens

Question 61

_{Treatment of Anaphylaxis During Anesthesia} Why must the patient be encouraged to carry an allergy card?

Answer 61

To be shown for any subsequent anesthesia exposure and Prevent re-exposure

Question 62

_{Treatment of Anaphylaxis During Anesthesia} How long must causative agents and drugs that cross react with a known allergen that had caused anaphylaxis be eliminated for the patient and become part of his/her permanent medical record?

Answer 62

**For life**!!!

Question 63

_{Treatment of Intraoperative Anaphylaxis} What are steps in the treatment of an anaphylactic reaction?

Answer 63

Discontinue the **offending agent** **Airway** support: Increase FiO2 and provide airway support **Epinephrine**: Start with 5-10 mcg IV for hypotension and 0.1-1 mg IV for CV collapse Liberal IV **hydration**: Crystalloid 10- 25 mL/kg or colloid 10 ml/kg (repeat if necessary) **H1-receptor antagonis**t: Diphenhydramine 0.5-1.0 mg/kg IV **H2-receptor antagonist**: Ranitidine 50 mg IV or famotidine 20 mg IV **Hydrocortisone** 250 mg IV (prevents delayed release of inflammatory compounds - does not produce an immediate effect) **Albuterol** for bronchospasm **Vasopressin** for refractory hypotension. Start at 0.01 unit/min