Anesthesia Outside of the OR Flashcards
Standards for Anesthesia Outside of the OR
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
The process from minimal sedation to general anesthesia is _______.
a continuum and individuals vary in their responses to medications
Level 1
Type: Minimal
Responsiveness: normal to verbal
Airway: unaffected
Spontaneous Respirations: unaffected
CV Function: unaffected
Level 2
Type: moderate
Responsiveness: purposeful response to verbal or tactile
Airway: no intervention required
Spontaneous Respirations: adequate
CV Function: usually maintained
Level 3
Type: deep
Responsiveness: purposeful after repeated or painful
Airway: intervention may be required
Spontaneous Respirations: may be inadequate
CV Function: usually maintained
Level 4
Type: general anesthesia
Responsiveness: unarousable
Airway: intervention often required
Spontaneous Respirations: often inadequate
CV Function: may be impaired
Specific Procedures
Cardiology Procedures
Gastroenterology Procedures
Gynecology Procedures
Psychiatric Procedures
Radiologic and Diagnostic Procedures
Pacemakers and Surgery
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
What will a magnet do to an AICD?
AICD: Magnet will suspend sensing and prevent a shock delivered
What will a magnet do to an AICD with pacemaker function?
AICD with pacemaker function: Suspends sensing and prevent a shock delivered, but has no effect on pacemaker function.
Electromechanical Interference (EMI) is greatest with ____
electrocautery and radiofrequency ablation
Different causes of interference
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
What is contraindicated with a pacemaker?
MRI is contraindicated
Lithotripsy and ECT is not contraindicated
No contraindications to succinylcholine
What are the options for when the pacemaker fails?
Transcutaneous pacing
Isoproterenol, epinephrine and atropine
Cardioversion
Atrial fibrillation and flutter are associated with congestive heart failure and formation of thromboembolism
Cardioversion is usually a scheduled procedure
Radiofrequency Catheter Ablation
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
Electroconvulsive Therapy
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
ECT Physiologic Response
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
Cerebrovascular changes with ECT
Seven fold increase in cerebral blood flow
Increase in cerebral oxygen consumption
Most common cause of death is _____ following ECT
myocardial infarction and cardiac dysrhythmias
Absolute Contraindications to ECT
Recent MI (<4-6months)
Recent intracranial surgery (<3 months)
Recent stroke < 3 months
Brain Tumor
Unstable cervical spine
Pheochromocytoma
Relative Contraindications to ECT
Pregnancy
Pacemaker ICDCHF
Glaucoma
Retinal detachment
Severe Pulmonary disease
Anesthesia for ECT
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
Anesthesia for CT
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.
Anesthesia for MRI
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.
4 Zones of MRI
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
Interventional Radiology
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
Ionization Radiation Risks
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
Biggest risk of radiation exposure (pregnant vs. non pregnant person)
In the non-pregnant person the eye and the thyroid are most susceptible to injury
In the pregnant person the fetus is most susceptible
How we can limit our exposure to radiation
Distance, duration and shielding
DISTANCE is an easy way to protect yourself from ionizing radiation
Minimum safe distance is six feet
Duration
Shielding
Inverse Square Law
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
Example of Inverse Square Law
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
What is the reported most common mechanism of injury that occurs with anesthesia outside of the OR?
inadequate oxygenation/ventilation
