asthma, bites, stroke Flashcards
simple, inexpensive ways of measuring the severity of airway obstruction in severe asthma exacerbation and are commonly used to monitor response to treatment in the ED
peak expiratory flow rate (PEFR) or FEV1
Severe asthma is defined as an FEV1 of less than 50% of predicted (typically less than 200 L/min in an adult) or one’s own personal best measurement
when to get ABG in asthma exacerbation
To determine degree of hypercapnea or assess degree of deterioration in tiring patient not yet sick enough to warrant endotracheal intubation
when to get CXR in asthma exacerbation
Temp +38°C Unexplained chest pain Leukocytosis Hypoxemia Comorbidities/alternative diagnosis
when to get EKG in asthma exacerbation
Persistent tachycardia
Comorbidities/alternative diagnosis
heliox in asthma? how does it work
produce a more laminar airflow and potentially deliver nebulized particles to more distal airways, but they have not been shown to consistently lead to improved ED outcomes, may be beneficial only in patients who present with severe asthma that is refractory to initial treatment
Oxygen should be provided to maintain a pulse oximetry reading of at least ? in adults and higher in whom?
90%
at least 95% in infants, pregnant women, and patients with coexisting heart disease
mainstay of asthma treatment
Albuterol
Typically 2.5 to 5 mg intermittently nebulized every 15 to 20 minutes for the first hour of therapy and then repeated every 30 minutes thereafter for 1 to 2 more hours
patients with severe obstruction or who cannot tolerate inhalation therapy (eg, children) are given
subQ administration of epi or terbutaline
Epi 0.3 to 0.5 mg subcutaneously every 20 minutes to a maximal combined total dose of 1 mg
Terbutaline is given 0.25 mg subcutaneously every 20 minutes up to a maximum of three doses. -preferable because of its beta-2 selectivity and fewer cardiac side effects
Levabuterol
typical dose for ipratropium bromide is ?
two puffs from a MDI with spacer device, or 0.5 mL of the 0.02% solution
when to use steroids in AE
Acute asthma in patients with moderate/severe asthma attack
Worsening asthma over many days (+3 days)
Mild asthma not responding to initial bronchodilator therapy or asthma that develops despite daily inhaled corticosteroid use
steroid dosing for AE
Oral administration of prednisone (dose 40-60 mg) is usually preferred to IV methylprednisolone (dose 125 mg), because it is less invasive and the effects are equivalent
alternatively: IM methylprednisolone, IV/oral dexamethasone, IV hydrocortisone
leukotriene antagonists and their role in asthma
zileuton (Zyflo Filmtab), zafirlukast (Accolate), and montelukast (Singulair)
only in the management of chronic asthma
what may benefit asthmatics with severe airway obstruction
magnesium sulfate given IV at dosages of 2 to 4 g
compete with Ca2+ for entry into smooth muscle, inhibit the release of Ca2+ from the SR, prevent acetylcholine release from nerve endings, and inhibit mast cell release of histamine
BiPAP in AE?
Severe asthmatics (defined as FEV1 less than 60% and RR +30) with impending respiratory failure should receive a trial of BiPAP prior to being intubated
Immediate rapid-sequence endotracheal intubation should be reserved for ?.
In an awake patient, an appropriate induction agent (eg, ?) and paralytic agent (eg, ?) should be used prior to intubation
unconscious or near-comatose patients with respiratory failure
ketamine
succinylcholine
why is ketamine the induction agent of choice?
it stimulates the release of catecholamines and causes relaxation of bronchial smooth muscle, leading to bronchodilation
IV infusion of 1 mg/kg, followed by a continuous infusion of 0.5 to 2 mg/kg/h
Once an asthmatic patient is intubated, the ventilator should be set to promote the goal of ?
permissive hypercapnea which aims at minimizing dynamic hyperinflation (ie, breath stacking or auto-PEEP) with low tidal volumes, and increased time for expiration, while limiting plateau pressures
Suggested initial settings for AE: Assist Control mode with what settings
respiratory rate of 8 to 10 breaths per minute, tidal volume 6 to 8 mL/kg, no extrinsic PEEP, inspiratory-to-expiratory (I/E) ratio of 1:4, and an inspiratory flow rate of 80 to 100 L/min. To prevent barotrauma, plateau pressures should not exceed 30 cm H2O
when can AE pts go home
An improvement of PEFR or FEV1 to greater than 70% predicted or personal best can also be used as a sign of objective improvement
Asthmatics who are discharged from the ED should receive ?
albuterol, an MDI spacer device, and a 5- to 10-day course of oral steroids
Glucagon has become an accepted antidote to ? poisoning because ?
beta-blocker
it stimulates cAMP synthesis independent of the beta-adrenergic receptor
use what to irrigate a wound
Sterile saline
povidone iodine, hydrogen peroxide, and detergents should be avoided because of their toxic effects on tissue
local anesthetic combos and uses (TAC and LET)
TAC (tetracaine, 0.25%-0.5%; adrenaline, 0.025%-0.05%; cocaine, 4%-11%) was commonly used initially, but was associated with seizure, arrhythmia, and cardiac arrest.
LET (lidocaine, 4%; epinephrine, 0.1%; tetracaine, 0.5%) is generally safer than TAC and is used for anesthesia of the face and scalp
