HA oral: Induction (rest), CXR, EKG Flashcards
How do you prevent recall?
Keep in mind the DOA of your induction agent in relation to the onset of your NMB
Induction dose of propofol will have a clinical effect/DOA = 10 minutes
May need additional induction drug available and administer as needed
Use inhalational/Volatile agent during ventilation
BIS monitoring
Recall is V-BAD
V.BAD
Volatile, Bis, Additional induction druv, DOA of agent in relation to NMB
RSI Definition
Rapid sequence intubation/induction (RSI) is an airway management technique that induces immediate unresponsiveness and muscular relaxation and is the fastest and most effective means of controlling the emergency airway.
Used in situations of full stomachs-at risk for aspiration
Adds the Sellick’s Maneuver and removes ventilation from the standard induction sequence
List standard induction steps
- MSMAIDS
- Position pt supine in sniffing position
- turn on oxygen flow & pre-oxygenate
- pre-induction medication
- lidocaine (+/-) induction agent
- wait until effect time. Check responsiveness & lash reflex
- Test ventilation (close APL valve, make sure can ventilate)
- check PNS
- paralytic drugs
- continue to ventilate until drug takes effect (recheck TOF)
- tape eyes
- scissor technique, laryngoscopy & intubate (inflate ETT, confirm placement, secure tube)
- continue ventilation by bag or switch to vent
- begin maintenance (overpressure va)
- check vent setting, observe expired VA and titrate down. give maintenance agent and abx
Rapid Sequence Induction (RSI):
Identify patient in need of RSI Pre-operative prophylaxis for aspiration Bicitra/Reglan/Omeprazole/Pepcid or Zantac Anxiolytic Narcotic (avoid loss of consciousness to early) Monitors on Suction on and at head of bed Supine-sniffing position Pre-oxygenate (spontaneously breathing) Sellick’s maneuver= cricoid pressure –gradually increase pressure as patient falls asleep Induction agent NO TEST VENTILATION
Extubation Criteria
Extubation Criteria – Respiratory Criteria for either fully awake or deeply anesthetized
TV >6mls/kg
VC >10 mls/kg
RR <30 breaths/min (Typically ~10 breaths/min. Make sure vent is turned off, pt must be spontaneously breathing!)
SaO2 >90%
EtCO2 <50 mmHg (COPD & asthmatics will naturally be higher, maybe 55 or 60 EtCO2 appropriate)
Sustained tetanic contraction with PNS
Nearly awake extubation
Muscle relaxant fully reversed and confirmed with PNS (if applicable)
All respiratory extubation criteria have been met
Anesthetic medications including volatile agents and infusions turned off
100% FiO2
Oropharynx suctioned
Patient is responsive to commands/purposeful movement
Sustained (5 second) head lift indicates clinically adequate reversal of NMB
Patient can maintain and protect own airway
ETT removed while positive pressure breath is given
deep extubation
Muscle relaxant fully reversed and confirmed with PNS (if applicable)
All respiratory extubation criteria have been met
Oropharynx suctioned
100% FiO2
Oral or nasal airway may be inserted
ETT removed while positive pressure breath is given
Volatile agents or infusions turned off
Mask airway maintained while patient spontaneously ventilating
Remain vigilant until patient is responsive and maintaining own airway
Cause & s/s of laryngospasm
Prolonged intense glottic closure
May present with high pitched squeak to total absence of sound (ominous sign)
Suprasternal and supraclavicular in-drawing,
increased diaphragmatic excursions
flailing of the lower ribs resembling a “rocking horse”
What muscles are involved in a laryngospasm
lateral cricoarytenoids
thyroarytenoids
cricothyroid
from stimulation of the vagus nerve
Most often seen during induction and emergence
laryngospasm triggers
Secretions (vomitus, blood, saliva) Foreign body Pain Pelvic or abdominal visceral stimulation Stimulating glottis in a light plane of anesthesia Reactive airway disease Loud noises (pediatrics)
S, F, P, V, L, R
Floppy Vocal Lips Shut Please Respond
Fuck! Vocal Lips Shut, Please Respond
laryngospasm prevention
Deep plane of anesthesia reached prior to surgical stimulation
Either fully awake or deeply anesthetized with extubation- not in-between (Avoid stage Two)
Suction oropharynx prior to extubation
Remove ETT with positive pressure breath
Prevent Sudden Airway Death
Positive P, Suction, Avoid st 2, Deepen
Laryngospasm treatment
Recognize the event!
Immediate removal of the offending stimulus
Larson maneuver
Retromandibular notch/ laryngospasm notch
condylar process of the mandibular ramus anteriorly, the mastoid process posteriorly, and the external auditory canal superiorly
Pressure for 3-5 seconds and released for 5-10 seconds
Administration OXYGEN (100% FiO2)
continuous positive pressure
Deepen anesthetic (propofol)
Small dose of short acting muscle relaxant: Succinylcholine 20-40 m
Pray LORRD Savior
Positive pressure continuous, Larsons, Oxygen 100%, Recognize, Remove, Deepen, Succs
justifications for CXR
pneumonia (confirmation) immunosuppressed pt COPD w/acute exacerbation foreign body CHF aspiration pneumonia blunt trauma lung tumor chest pain suspected pneumothorax SOB (severe) hemoptysis pulmonary HTN PE interstitial lung ds ICU pt (adm, inv lines, ETT
basic tissue densities**
Black = Air
Dark gray = Subcutaneous tissue, Fat
Light gray = Soft tissue (muscles, heart, blood vessels, pus, etc.)
Off white = Bone
Bright white = Metal (pacemakers, surgical clips, bullets, etc.)
What does CXR position affect?
Magnification
Organ position
Blood flow
Gravitational pull*
Position Makes Bad Organs Good
causes of pneumothorax
Causes: Trauma Subclavian venous catheter, Liver biopsy Spontaneous (result of a bleb rupture) Metastatic tumors
EMS - Emergency (trauma, liver puncture), metastatic tumor, Spontaneous bleb & SVC
tension pneumothorax definition
Tension pneumothorax = mediastinal shift occurs or there is depression of the hemidiaphragm with displacement of the heart and trachea to the unaffected side
pneumothorax on CXR
UPRIGHT is the best position
Where is the first place to look for pneumothorax? Right and left upper hemithoraces
Supine: Deep Sulcus Sign
pleural effusion : Definition, Looking for? Causes? Best CXR position
Definition: collection of fluid between the visceral and parietal pleura (~100 mL to detect on upright CXR)
Look for:
- Blunting costophrenic angles
- inc basilar density (whiteness)
- loss of nL lung hemidiaphragm
Causes:
Malignancies
Pancreatitis (LEFT-sided pleural effusion)
Cirrhosis (RIGHT-sided pleural effusion)
CHF (BILATERAL pleural effusion, usually associated w/cardiomegaly)
Pneumonias
[PCCCC- Pancreatitis, CA(malignancies), Cirrhosis, CHF, Consolidation (PNA)]
Best XR position: Upright
mediastinal shift in tension pneumonia, atelectasis, airway obstruction?
-Tension pneumothorax: the mediastinum is shifted toward the unaffected side (PUSHING IT)
-Atelectasis: collapse of entire lung segment might result in severe volume loss.
Mediastinal shift toward the affected side (PULL TOWARDS, like suction)
-Airway obstruction: mediastinal shift toward the unaffected side (can’t get out, builds up, push it)
male vs female CXR
Nipple shadows common in men and women
compare both sides
Overlying breast tissue accentuate pulmonary vasculature
(careful, not to dx as infiltrate/pneumonia)
can tape metallic BB or other metal object and reshoot film
silhouette sign on CXR
It helps to determine the location of an abnormality in relation to normal structures
Loss of a normal border occurs if an abnormality is contiguous with that structure
RML vs RLL (pneumonias, masses)
- Loss of right heart border indicates that the infiltrate is in the RML (right middle lobe)
- Loss of right hemidiaphragm indicates that the infiltrate is in the RLL (right lower lobe)
- Loss of left heart border indicates that the infiltrate is in the lingula of LUL (left upper lobe)
- Loss of left hemidiaphragm indicates that the infiltrate is in the LLL (left lower lobe)
When would you perform a CXR in a suspected Aspiration PNA?
Aspiration: the inhalation of gastric contents (following seizure, cardiac resuscitation, anesthesia-related complication)
CXR usually performed immediately after incidence
Follow-up should be performed within 12 hrs.
May take several hours for the gastric contents to react with the lung to cause fluid exudate and an alveolar infiltrate
What masses are found in the anterior mediastinum ?
Anterior Mediastinum (4 Ts): lesion filling in the space behind the top of the sternum and the ascending aorta
Thymoma
Thyroid lesions
Teratoma (germ cell tumors, most commonly seen in males)
T cell lymphoma
(4Ts)
What is found in the middle mediastinum ?
Middle Mediastinum (any lesions associated w/the aorta should be considered an aneurysm until proven otherwise)
Thoracic aortic aneurysm
Neoplasms
Adenopathy
Diaphragmatic hernias
(another T-AND)
What is found in the posterior mediastinum?
Posterior Mediastinum (lateral view CXR projecting over the spine and are also paraspinous on the frontal CXR)
Neurogenic (90%)
Neuroblastomas (children)
Neurofibromas (adults) Schwannomas (adults)
Ganglioneuromas (adults)
(Neuro shit)
systematic approach for CXR interpretation?
Who (correct patient)
What (film orientation) AP, PA, supine, upright
When (date)
Why (reason for X-ray) history and PE are extremely important
Exposure?
Airway.
Bones.
Cardiac. Diaphragm/mediastinum. Everything else
Conduction system
Sinoatrial node: 60-100 bpm
Atrioventricular node: delays conduction for ventricular filing; initiates impulse 40-60 bpm
Bundle of His: directs impulse to left/right bundle branches
Purkinje fibers: reaches into myocardium to stimulate ventricular depolarization/ contraction. Initiates impulse 20-40 bpm
EKG basics and vectors
Electrocardiogram (EKG) is the graphic display of the flow of electrical activity (action potentials) generated by myocytes.
Action potentials travel in all directions but the average (mean) current (vector) is measured by the EKG.
There are two main vectors
Vector of depolarization = QRS complex
Vector of repolarization = T wave
3 lead EKG placement and poles
Electrodes placed on the skin are used to identify these poles.
Right Arm is always negative
Left Leg is always positive
Left Arm is positive in lead I and negative in lead III
standard limb leads
Lead I: negative electrode on right upper limb to the positive electrode on left upper limb
Corresponds to a view of the lateral wall of the heart and areas supplied by the circumflex artery
Lead II: negative electrode on right upper limb to positive electrode on left lower limb
Corresponds to a view of the inferior wall of the heart and the areas supplied by the right coronary artery
Lead III: negative electrode on left upper limb to positive electrode on left lower limb
Corresponds to a view of the inferior wall of the heart and the areas supplied by the right coronary artery
augmented limb leads
aVR: Right arm electrode is positive, and the left arm and left leg electrodes are channeled together to form a common reference point that has a negative charge
aVL: Left arm electrode is positive, and the right arm and left leg electrodes are channeled together to form a common reference point that has a negative charge
Corresponds to a view of the lateral wall and areas supplied by the circumflex artery
aVF: Left foot electrode is positive, and the right arm and left arm electrodes are channeled together to form a common reference point that has a negative charge
Corresponds to a view of the inferior wall of the heart and areas supplied by the right coronary artery
precordial leads
The positive poles are on the anterior and lateral chest and the negative poles are on the opposite side of the positive pole
V1: positive electrode placed directly over the right atrium
Corresponds to the septal wall and areas supplied by the LAD (left anterior descending artery)
V2: positive electrode placed just anterior to the AV node
Corresponds to the septal wall and areas supplied by the LAD
V3 and V4: positive electrode placed over the ventricular septum
Corresponds to the anterior wall of the heart and areas supplied by the LAD
V5 and V6: positive electrode placed over the lateral surface of the left ventricle
Corresponds to the lateral wall of the heart and areas supplied by the circumflex artery
12 lead EKG view
Lead V1, V2 view the septal wall and LAD
Lead V3, V4 view the anterior wall and LAD
Lead I, aVL, V5, V6 view the lateral wall and circumflex.
Lead II & III and aVF view the inferior wall of the heart supplied by RCA
5 lead EKG
Takes a standard three lead system (right limb electrode, left limb electrode and left leg electrode) and adds a right leg and chest electrode.
By adding the right leg lead electrode any of the six limb leads can be viewed.
The chest electrode (V1) can be moved to any of the precordial V positions to obtain all six precordial views
vector of depolarization= QRS complex
Heart depolarizes from base to apex and endocardium to epicardium
Myocytes go from internally negative to internally positive produces a positive electrical current
Positive deflection on the EKG occurs when vector of depolarization travels towards a positive electrode
Negative deflection on the EKG occurs when vector of depolarization travels away from a positive electrode
Biphasic deflection on the EKG occurs when vector depolarization travels perpendicular to positive electrode
vector of repolarization= Twave
Heart repolarizes from apex to base and epicardium to endocardium
Myocytes go from internally positive to internally negative produces a negative electrical current
Positive deflection occurs when the wave travels away from a positive electrode
normal EKG measurement
PR interval measurement (Normal: 0.12 - 0.2)
QRS interval measurement (Normal: <0.12)
QT interval measurement (Normal: <0.45 men, <0.47 women
left axis deviation
Left axis deviation has a positive R wave deflection in lead I but negative R wave deflection in aVF Leaving each other = Left axis deviation Causes of left axis deviation (conditions that make the left side of the heart work harder or hypertrophy) Chronic HTN LBBB Aortic stenosis Aortic insufficiency Mitral regurgitation
right axis deviation
Right axis deviation has a negative R wave deflection in lead I but positive R wave deflection in aVF
Reaching each other = Right axis deviation
Extreme right axis deviation has negative R wave deflections in both lead I and aVF
2 thumbs down = BAD
Causes of right axis deviation (conditions that make the right side of the heart work harder or hypertrophy) – reaching for each other; or extreme; both down
COPD
Acute bronchospasm
Cor pulmonale
Pulmonary hypertension
Pulmonary embolism
Myocardial ischemia wall infarcts
Inferior Wall Ischemia (Right coronary artery & Posterior interventricular branch): II, III, and aVF
Lateral Wall Ischemia (Circumflex branch of the left coronary artery): I, aVL, V5, V6
Septal Ischemia (Left anterior descending artery): V1-V2
Anterior Wall Ischemia (Left anterior descending artery): V3 -V4
Anterior-septal (Left anterior descending artery): V1-V4
preop assessment for cancer and general adverse effects
1) Surgery, (2) Chemotherapy, (3) Radiation therapy
Toxicities/Adverse Effects have the potential to affect nearly every organ system
Bone marrow suppression
CV toxicity
Pulmonary toxicity
Central and peripheral nervous system damage
Nutritional status (e.g., alopecia, N/V/D)
systems affected by radiation and clinical effects
skin-acute-erythema, rash, hair loss; chronic-fibrosis, sclerosis, telangletasias
GI- acute-malnutrition, mucositis, n/v; chronic- adhesions, fistulas, strictures
cardiac- conduction defects, pericardial effusion, pericardial fibrosis, pericarditis
respiratory- airway fibrosis, pul. fibrosis, pneumonitis, tracheal stenosis
renal- acute-glomerulonephritis; chronic-glomerulosclerosis
hepatic- sinusoidal obstruction syndrome
endocrine- hypothyroidism, panhypopituitarism
hematologic- acute-bone marrow suppression; chronic- coagulation necrosis
preop assessment for cancer patient
HISTORY & CO-MORBITITIES?
Malignancy in the head or neck
Airway exam and possible need for tracheostomy
Recurrent laryngeal nerve damage (S/S: hoarseness)
Mediastinal masses obstructing great vessels
Trachea compression manifestations: Dyspnea, dysphagia, stridor, wheezing, coughing recumbent position
SVC compression manifestations: Compression of SVC JVD & facial, chest, neck, upper extremity edema
Preop testing:
Ultrasound, CT, MRI
Flow volume loops to see how much their expiratory volume has been impaired
EKG, ECHO
Anesthetic concerns:
Radiation to neck can lead to tracheal stenosis smaller airway may have trouble getting ETT in
If someone has a mass obstructing the trachea and you can’t lay them back, how are you going to get them to sleep?
Spontaneous awake and ENT at bedside
“Radical neck procedures” may need to be converted to a trach at the end of the case
when is expiration CXR useful?
small pneumothorax: expiration will make the lung smaller and denser, and at the same time will relatively make the pneumothorax appear larger
lodged foreign body: “ball-valve phenomenon” – air can move past the object during inspiration, but during expiration (the bronchus gets smaller) and air can not exit around the obj. As a result, the expiration image will show air trapping in the affected lung and a mediastinal shift will occur toward the unaffected side
compare AP vs PA view
AP (supine) Xray beam entering anterior thorax, exit posterior pt position: supine detector position: on back heart size magnified diaphragm (cephalad)
PA view (upright) x-ray beam enter posterior thorax, exit anterior position: upright detector position: front heart size (true to size) diaphragm (caudad)
Downfalls of a supine CXR
- limits full inspiration
- cephalic push
- small pleural effusions layer in posterior pleural space and can easily be misssed
- be careful when interpreting
compare and contrast overexposure vs underexposure
overexposure:
Image is dark
Easy to see: Thoracic spine, clavicles, behind the heart, NG & ET tube placement
Cannot see: pulmonary vessels in the periphery, small nodules, or fine structures
(bones and hard stuff)
Underexposure: Image is white
Easy to see: pulmonary vasculature (don’t mistake for infiltrate)
Cannot see: behind the heart, spinal anatomy, or behind hemidiaphragms
(soft tissue and vasculature)
Considerations when doing an upright CXR
- inspiration is greater
- domes of hemidiaphragm at posterior T10 level
- Hypoinflation - dome at 7th rib
