Anesthesia Outside of the OR

Question 1

Standards for Anesthesia Outside of the OR

Answer 1

Anesthesia equipment check
Monitor and document
Reduce risk of infection
Transfer of care to a qualified provider to ensure quality of care and patient safety

Question 2

The process from minimal sedation to general anesthesia is _______.

Answer 2

a continuum and individuals vary in their responses to medications

Question 3

Level 1

Answer 3

Type: Minimal
Responsiveness: normal to verbal
Airway: unaffected
Spontaneous Respirations: unaffected
CV Function: unaffected

Question 4

Level 2

Answer 4

Type: moderate
Responsiveness: purposeful response to verbal or tactile
Airway: no intervention required
Spontaneous Respirations: adequate
CV Function: usually maintained

Question 5

Level 3

Answer 5

Type: deep
Responsiveness: purposeful after repeated or painful
Airway: intervention may be required
Spontaneous Respirations: may be inadequate
CV Function: usually maintained

Question 6

Level 4

Answer 6

Type: general anesthesia
Responsiveness: unarousable
Airway: intervention often required
Spontaneous Respirations: often inadequate
CV Function: may be impaired

Question 7

Specific Procedures

Answer 7

Cardiology Procedures
Gastroenterology Procedures
Gynecology Procedures
Psychiatric Procedures
Radiologic and Diagnostic Procedures

Question 8

Pacemakers and Surgery

Answer 8

Use of a Magnet on a pacemaker: Without knowing the specific model we do not know how a magnet will affect a pacemaker.
A magnet could convert to asynchronous mode

Question 9

What will a magnet do to an AICD?

Answer 9

AICD: Magnet will suspend sensing and prevent a shock delivered

Question 10

What will a magnet do to an AICD with pacemaker function?

Answer 10

AICD with pacemaker function: Suspends sensing and prevent a shock delivered, but has no effect on pacemaker function.

Question 11

Electromechanical Interference (EMI) is greatest with ____

Answer 11

electrocautery and radiofrequency ablation

Question 12

Different causes of interference

Answer 12

Coagulation setting causes more interference than cutting setting
Monopolar cautery causes more than bipolar or Harmonic scalpel
If monopolar is needed recommendations are for short bursts (< 0.5 sec) and use at least a 15cm radius away from pacemaker
Place the electrocautery return pad far away from the pacemaker and in a location that prevents a direct path of current through the pacemaker

Question 13

What is contraindicated with a pacemaker?

Answer 13

MRI is contraindicated
Lithotripsy and ECT is not contraindicated
No contraindications to succinylcholine

Question 14

What are the options for when the pacemaker fails?

Answer 14

Transcutaneous pacing
Isoproterenol, epinephrine and atropine

Question 15

Cardioversion

Answer 15

Atrial fibrillation and flutter are associated with congestive heart failure and formation of thromboembolism

Cardioversion is usually a scheduled procedure

Question 16

Radiofrequency Catheter Ablation

Answer 16

RFCA is used to treat many arrhythmias in adult and pediatric patients
RFCA requires general anesthesia patients need to remain still and procedures can be long
Esophageal temperature probe
Careful monitoring of hemodynamics
Fluid management

Question 17

Electroconvulsive Therapy

Answer 17

The exact mechanism for its therapeutic effect remains unknown

Electrically induced seizures of at least 25 seconds in duration are necessary for therapeutic effect

The electrical stimulus produces a grand mal seizure consisting of a brief tonic phase and a more prolonged clonic phase

Indicated for the treatment of medication resistant depression, mania, catatonia, suicidal ideation and schizophrenia

Question 18

ECT Physiologic Response

Answer 18

Initial response or tonic phase (15 sec)
Increase PNS: Bradycardia, hypotension and increase secretions

Secondary Phase or clonic phase (minutes)
Increase SNS: Hypertension tachycardia increased gastric pressure increased CBF, increased Intracranial pressure and increased IOP

Question 19

Cerebrovascular changes with ECT

Answer 19

Seven fold increase in cerebral blood flow
Increase in cerebral oxygen consumption

Question 20

Most common cause of death is _____ following ECT

Answer 20

myocardial infarction and cardiac dysrhythmias

Question 21

Absolute Contraindications to ECT

Answer 21

Recent MI (<4-6months)
Recent intracranial surgery (<3 months)
Recent stroke < 3 months
Brain Tumor
Unstable cervical spine
Pheochromocytoma

Question 22

Relative Contraindications to ECT

Answer 22

Pregnancy
Pacemaker ICDCHF
Glaucoma
Retinal detachment
Severe Pulmonary disease

Question 23

Anesthesia for ECT

Answer 23

Methohexitol is the drug of choice used for induction of general anesthesia for ECT 0.5-1mg/kg
Minimal anticonvulsant effects
Propofol is an alternative to methohexital
Lower blood pressure and HR response to ECT
Recovery is similar to methohexitol
Anticonvulsant effect of propofol can shorten seizure duration
Ketamine and etomidate improve the quality and duration of seizures but ketamine prolongs recovery and etomidate is associated with more hypertension and possibility of spontaneous seizures before ECT

Question 24

Anesthesia for CT

Answer 24

CT scans are usually performed without general anesthesia. Children and uncooperative adults (e.g., head-injured patients) may require sedation or general anesthesia to minimize motion artifacts.

Capnography is useful to provide evidence of ventilation during sedation; fitting a side-stream sampling tube to nasal cannula or oxygen facemask provides qualitative assessment of ventilation.

Adults: small IV doses of a benzodiazepine, a narcotic, or a short acting hypnotic (e.g., propofol) are useful for sedation; continuous infusions should be titrated to effect.

Laryngeal mask airway (LMA) or endotracheal intubation may be necessary to maintain a patent airway during deep sedation or general anesthesia.

Question 25

Anesthesia for MRI

Answer 25

The “missile effect” refers to the capability of the fringe field component of the static magnetic field of an MR system to attract a ferromagnetic object, drawing it rapidly into the scanner by considerable force. Obviously, the missile effect can pose a significant risk to the patient inside the MR system and/or anyone who is in the path of the projectile.

Prevention of missile effect is accomplished by accounting for all ferromagnetic objects in the operating room through multiple counts and cross checks and ensuring their removal to outside the 5 Gauss line prior to bringing the MRI into the OR for the purposes of scanning.

Question 26

4 Zones of MRI

Answer 26

Zone 1: Public access - Hallway
Zone 2: Public access and limited supervision – Entrance to suite
Zone 3: Limited access and explicit supervision – Immediately outside the scanner
Zone 4: Strict and controlled access – The scanner room

Question 27

Interventional Radiology

Answer 27

IR involves minimally invasive procedures and therapies on mostly high risk patients

RFCA and microwave therapy to treat respiratory, renal and hepatic tumors
Major IR therapies include angiography, embolization of blood vessels, vascular occlusion, removal of thrombus, ablation of aneurysms and angioplasty with stent placement

Question 28

Ionization Radiation Risks

Answer 28

Tissue Injury, chromosomal damage, and malignancy
The roentgen (R) is how we measure exposure
A roentgen in man (rem) is a measure of exposure to damaging radiation
The yearly max radiation exposure is 5 rem
The yearly max for a fetus of a pregnant worker is 0.5 rem or 0.05 rem/month

Question 29

Biggest risk of radiation exposure (pregnant vs. non pregnant person)

Answer 29

In the non-pregnant person the eye and the thyroid are most susceptible to injury

In the pregnant person the fetus is most susceptible

Question 30

How we can limit our exposure to radiation

Answer 30

Distance, duration and shielding
DISTANCE is an easy way to protect yourself from ionizing radiation
Minimum safe distance is six feet
Duration
Shielding

Question 31

Inverse Square Law

Answer 31

Exposure is inversely proportional to the square of the distance from the source

Intensity = 1/Distance^2
Set up a Proportion:
Intensity1 = Distance2^2
Intensity2 = Distance1^2

Question 32

Example of Inverse Square Law

Answer 32

During a cardiology procedure for pacemaker placement a patient receives 50mR at a distance of 1 foot, How much radiation with the anesthesia provider receive at 6 feet?
Intensity 1 = 50mR
Intensity 2 = x
D1 = 1
D2 = 6
50/x=6^2/1^2
50/x=36/1
36x=50
X= 0.72mR

Question 33

What is the reported most common mechanism of injury that occurs with anesthesia outside of the OR?

Answer 33

inadequate oxygenation/ventilation