Anesthesia in Remote Locations Flashcards
1
Q
Concerns with anesthesia in remote location?
A
- Cultural differences betwen NORA (non-OR anesthesia) locations
- working with medical interventionist instead of surgeons. may not be used to anesthesia standards
- New technologies, modalities, be prepared to ask a lot of questions
- Sometimes NORA cases are deemed “too sick for surgery”
- vigilance is key
- remote locations claims for death 54% versus 29% in OR
2
Q
Satellite location equipment checklist per ASA standards?
A
- Reliable oxygen source with back-up- e-cylinders available for back up
- Suction source- make sure it’s strong enough!
- Waste gas scavenging- if you don’t have scavenging, have to do TIVA
- Adequate monitoring equipment
- Must meet ASA and AANA basic standards- must have all monitors, including ETCO2
- During case & during post- anesthesia transport
- Self inflating hand resuscitator bag
- >90% FiO2 delivery
- Sufficient safe electrical outlets- must be able to handle all anesthesia equipment
- if working in wet environment- make sure electrical outlets are isolated or have a ground fault
- Adequate patient and anesthesia equipment illumination with battery power back-up
- Adequate space to freely access patient and anesthesia equipment
- Emergency cart with defibrillator , emergency drugs and other emergency equipment
- needs to be checked often
- Reliable two way communication to request for help
- Adequately trained support staff in procedure room & in post-anesthesia care location
- staff need to be trained to appropriately assist CRNA/MDA in event o femergency
- Anesthesia professional available throughout recovery period
- Compliance with facility with all applicable safety and building codes
3
Q
Monitoring required in remote environments
A
- Standards/routines utilized in the OR must be maintained - same time out and checklists used in OR
- Pre- and post-procedure checklists
- Emergency protocols with contact numbers should be posted
- if only anesthesia provider, do drills so staff can help in event of emergency (ie MH)
- ASA/AANA guidelines require evaluation of patient’s
- Oxygenation
- Ventilation
- Circulation
- Temperature
4
Q
Limitation/concern with remote locations?
A
- Design of satellite location is for the procedure - Anesthesia is an after-thought
- Personnel may be less familiar with mgt. of pts. under anesthesia
- Procedure table limits
- may not be able to sit HOB up
- Pre-procedure assessment/optimization often not completed in advance= delays + cancelations
5
Q
What is minimal sedation?
A
anxiolysis
- drug-induced sedation
- patient responds normally to verbal commands
- cognitive and motor function may be impaired
- ventilatory and CV function maintain normally
6
Q
What is moderate sedation (conscious sedation)
A
- Drug-induced sedation
- patient responds purposefully to verbal commands either alone or with light tactile stimulation
- patients maintain a patent airway and spontaneous ventilation
- CV function maintained
7
Q
What is deep sedation
A
- Drug-induced sedation
- patient not easily aroused but can respond purposefully to repeated or painful stimulation
- ventilatory function may be impaired, requiring assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate
- CV function usually maintained
8
Q
What is General anesthesia?
A
- Drug induced loss of consciousness
- patients not aroused by painful stimulation
- ventilatory function often impaired, the patient may require assistance in maintaining a patent airway
- spontaneous ventilation and neuromuscular functioning may be impaired
- positive-pressure ventilation often required
- CV function may be impaired
9
Q
What is MAC sedation? position statement?
A
- component of MAC is anestheisa assessment and management of patient’s actual or anticipated physiological derangmeents or medical problems that may occur during diagnostic or therapeutic procedure.
- may involve administration of sedatives and/or analgesics
- provider must be prepared and qualified to convert to general anesthesia and the ability to intervene to rescue a patient’s airway form any sedation-induced compromise
*
10
Q
What is an EGD?
A
esophagogastroduodenoscopy
- Fiberoptic endoscopic evaluation of the esophagus, pylorus, & stomach
- May involve biopsy, mucosal/submucosal dissection, dilation, stenting, etc.
- Local oropharyngeal anesthesia w /opioid + benzo VS general anesthesia with propofol
-
Aspiration and laryngospasm common
- need to keep patient extremely deep
- sometimes hard to do- may need dexmedetomidine or remifent and adjunct
-
topicalizing airway also helps
- gargle lidocaine
- spray lido in back of pharynx.
- look for full stomach on scope
- need to keep patient extremely deep
-
High risk groups: obese, OSA, GERD, asthma, obstruction/full stomach, hepatic disease
- hepatic dx- full stomach, coag issues, ascites<– intubate with RSI
- asthmatics- do prophylactic alburterol
- Consider ETT or Proseal LMA can be used (pediatric endoscope can fit through gastric drainage port)
- LMA not ideal, gets in way
- proseal better and can fit ped scope down gastric drainage port
11
Q
Lower endoscopy: sigmoidoscopy and colonoscopy
A
- Often a screening procedure with visualization of the lower GI tract to sigmoid colon or distal ileum but it may involve biopsy, polypectomy/mucosal resection, stenting, dilation,etc.
- Involves air insufflation, may involve the application of external pressure (increase aspiration risk)
- Benzos + opioids VS propofol (GA)
- some GI docs say propofol gives better scope
- typically less stimulating compared to upper endoscopy
-
could consider glyco to decrease airway secretion and decrease r/f laryngospasm
- may cause urinary retention
12
Q
ERCP considerations?
A
- Fluoroscopic exam of biliary and pancreatic duct that may involve stenting/removal of stones/laser lithotripsy
- 20-80 minutes, can be uncomfortable
- scope used to inject contrast through duodenal papilla
- Commonly performed in patients with cholangitis, pancreatitis, bile duct obstruction, pancreatic cancer, etc.
- concern for sepsis, can be medically fragile
- Requires immobile patient
- typically always intubate
- Often done in prone position- not in prone at GUH
- May involve CO2 insufflation (hypercarbia)
- same concerns with lap sx
- GA w/ETT is preferred
- procedural failure are twice as high when pt under sedation vs GA
- complication rate for GA may be lower
13
Q
What is a NOTES?
A
Natural Orifice Transluminal Endoscopic Surgery (NOTES)
- Procedure is in early phases of development
- cases require pneumoperitoneum and general anesthesia
- peroral endoscopic myotomy is an example (POEM)
- Gastroenterologists may use to treat esophageal achalasia
- high aspiration risk
- Esophageal insufflation w/CO2 followed by mucosal incision from mid-esophagus to proximal stomach
- Similar complications as expected with CO2 insufflation in laparoscopic surgery
- potential risk of insufflation range from SQ emphysema to PT, penumomediastinum, pneumoperitoneum
- procedure may take several hours and best accomplished under GA with ETT
- Gastroenterologists may use to treat esophageal achalasia
14
Q
Rigid bronchoscopic procedure concerns
A
- Endobronchial stenting, biopsy, laser therapy, dilation, cryotherapy, fiducial marker implant, etc.
- fiducial markers placed to assist with steriotactic radiosurgery
- Patients often have significant CV and pulmonary disease.
- COPD, lung CA, chronic aspiration, ETOH, etc
- TIVA preferred method
- can’t use VA- not consistent and polluting environment
- Propofol, remifentanil, dexmedetomidine + muscle relaxants
- MR nice to prevent coughing, also placing fiducial markers which need to be precise
- HFJV (high frequency jet ventilation) can be used to provide ventilation
- Associated complications = airway fire, bronchospasm, bleeding and hypoxia
- limit O2 if you can
15
Q
Radiology suite general considerations
A
- Patient remains immobile for prolonged periods
- may need GA just because it’s rather uncomfrotable
- Bulky equipment (C-arms, X-ray tubes, screens, etc.):
- impede access to patient
- Move and collide with anesthesia equipment
- Lines, pumps, ventilation tubing
- Will need EXTENSIONS
- Lack of scavenging may limit inhalation anesthetic agent techniques
- patients can be sicker than those undergoing conventional surgery
- lack of proper preop workup
-
diversity of procedures. 3 features in common
- 1) no surgical incision
- 2) imagery involved fluoro, US, CT, PET, MRI
- 3) Access to the target site (tumor, vasculature, organ) is via a small insertion site and catheters/wires
16
Q
Dose exposure consideration for radiology?
A
- Limit Radiation Exposure
- Dose-related cell death, tissue damage and malignancy (DNA ionization & free radical generation)
- Patient: direct exposure- highest risk is patients
- Occupational: mostly scatter from the x-ray beam
-
scatter exposure 1/1000 of direct if you are at least 1 m from the source
- radiaiton inverse square of distance from radiation source
-
scatter exposure 1/1000 of direct if you are at least 1 m from the source
- “ALARA”- as low as reasonably acheiveable
- Lead aprons
- Thyroid shields
- Moveable leaded glass screens
- Leaded eyeglasses
- Remote or video monitoring when appropriate
- Very Briefly stepping out of the room during imaging
- Dosimeters should be worn
- One under lead apron
- One on collar above lead apron
17
Q
Occupational limit for expsoure?
A
50 mSv in 1 year
10mSv per age in years- when younger should limit exposure further
18
Q
Contrast media condierations
A
- Used in diagnostic and therapeutic radiologic procedures (general radiology and MRI)
- Variable osmolarity; ionic or nonionic
- higher the osmolarity, and ionic contrast agents are associated with dose and concentration-dependent adverse reactions in 5-8% of pt
- low osmolarity has less risk for adverse reactions
- Adverse reactions range from mild to life threatening
- Hypersensitivity
- CO2 can be used if contrast absolutely contraindicated
- Renal toxicity
- Hypersensitivity
-
Idiosyncratic reactions unrelated to dose or concentration administered. Can be severe and include:
- laryngeal edema
- bronchospasm
- pulmonary edema
- hypotension
- respiratory arrest or seizures
- TXMT- O2, epi, bronchodilators
-
Pretreatment if hx of contrast reactions:
- contrast reaction, steroids, diphenhydramine
19
Q
Contrast hypersensitivity treatment?
A
- prompt recognition
- oxygen
- bronchodilators
- epinephrine
- fluid resuscitation
- corticosteroids
- Consider pretreatment with IV corticosteroids a few hours pre-procedure as well as H1 and H2 blockers
20
Q
Contrast induced nephropathy considerations
A
- Direct tubular toxicity due to release of free oxygen radicals and microvascular obstruction
- incidence 7-15%
-
Increased risk in
- Diabetic renal insufficiency
- Hypovolemia
- Congestive heart failure
- HTN
- Baseline proteinuria/renal disease
- Gout
- Co-administration of other drugs that cause renal tx
- Azotemia starts at
- 24-48 hours
- peaks at 3-5 days monitor creatinine levels (increase of 0.5mg/dL within 24 hrs is diagnostic)
- Avoid surgical procedures during this period
- 3rd leading cause of hospital acquired renal failure
- intra-arterial injection higher risk than IV admin
- d/c metformin before contrast given- if this develops, increased r/f lactic acidosis
21
Q
How to minimize the effects of contrast
A
- Effects of Contrast can be minimized
- Careful administration and limitation of total dose
- Hydration 1st line protection administer 1ml/kg of normal saline 4 hours pre-procedure and continue for 12 hours post-procedure (Avoid volume overload in susceptible patients)
- Administer sodium bicarbonate to promote renal elimination
- Monitor serum creatinine for 72 hours
- hydration only real protection against CIN
22
Q
Coagulation status optimization before radiology procedures?
A
- During percutaneous interventions bleeding can be occult
- Patients often receive anticoagulants (to prevent clotting in response to foreign bodies in vessels)
- INR <1.5, plt count >50,000
-
Hold medications
- warfarin 5-7 days
- ASA and clopidogrel 5 days
- Fractionated heparin 12-24 hours
- Heparin infusion 4-6 hours
- NSAIDS held 1-2 days
23
Q
Angiography: arteriography and venography purpose?
A
- Used to characterize atherosclerotic and ischemic lesions, the arterial supply of tumors and vascular anomalies, and traumatic injury.
- After diagnostic imaging, interventions using balloons, stents, balloon-mounted stents, thrombolytic therapy, embolic agent, filters or delivery catheters may take place
-
may use embolic agents
- coils/balloons/glue or chemical agents
- thrombolytic therapy- TPA, urokinase
-
may use embolic agents
