GA: Emergence - Exam 2 Flashcards
Ways to emerge more smoothly(time wise):
-SA agents for short cases
-avoid excessive premed
-prepare to switch techniques/ agents at end of long case
-time meds and doses
GA components that affect emergence timeframe
-FGF (high=fast, low=slow) ***
-Ventilation (hyper=fast, hypo=slow)
-Concentration gradient (BG and OG coefficients)
-Eliminating rebreathing (high FGF)
-pts BMI (high, may last longer)
-duration of GA (IA can take days to wear off -lipid soluble, maybe sent to ICU on vent)
-type of surg (neck and airway surg, do NOT want pt coughing on emergence, maybe emerge DEEP)
Until FiAA reaches _ on gas analyzer you are still giving IA to pt
0
You have washed your pt’s IA out with high MV and high FGF of O2, why aren’t they breathing?
Could have also washed out CO2 to a point where hypercarbic reflexes are diminished
-back off on higher flows, slow their RR maybe, shorter exp time may help
How will I know when my TIVA pt should be waking up?
know your beta half lives!
TOF adductor pollicis or orbicularis oculi
-twitches to receptor block %
-time to recovery
1= 90% blocked - 30min
2= 80% blocked - 3-15min
3= 75% blocked - 3-15min (still 30 min for pancuronium)
4= 0-70% blocked -<5min
Onset of paralysis happens in this order:
-eye muscles, extremities, trunk, diaphragm
-will recover in opposite order so monitor facial n on induction and ulnar n for recovery
T/F You should give anticholinergics to reverse NMBD if you don’t have any twitches.
no, try PTC if 0/4 on TOF
-1 twitch = reversal in 30 min
-2-3 twitches = recovery in 4-15 min
-4/4 twitches = total recovery in 5 min
If pt is 75% blocked per TOF they can have:
-5 sec head lift
-15-20mL/kg VC
–25cmH2O NIF
-effective cough
TOF outputs should be _mA
30
For monitoring recovery from NMBD which is better, quant or qual?
quantitative data
When can I reverse my NMBD?
Must have 1 TOF twitch
-also consider timing+conc of last dose + if spont resp effort is seen
If I don’t have any TOF twitches but use PTC and have 7-8 twitches will I have 1 TOF twitch soon?
Yes, like <10 min
-more twitches, sooner until TOF will give a twitch
Which NMBD wears off the slowest according to PTC?
PANCuronium
-by 6-10 twitches most other NMBD have given 1 TOF twitch but PANCuronium will usually give 1TOF by 11 twitches
How do anti(acetyl?)cholinesterase drugs work for reversal?
increase amount of ACh at receptors by preventing their breakdown EVERYWHERE
-hence following MUSCARINIC effect of bradycardia which it treated with antimuscarinics :)
T/F Neostigmine is an anticholinergic
HELL NAW, its an AChE inhibitor!!! -increases ACh
AChE Inhibitors
-Edrophonium dose, onset, DOA
0.5-1mg/kg
onset: 30-60 sec, peak:1-5 min
DOA: 5-20 min
AChE Inhibitors
-Edrophonium tips
-only administer if pt has 4 visible twitches
-goes better w/ Atropine bc similar onset
AChE Inhibitors
-Neostigmine dose, max, onset/peak, DOA
0.04-0.08 mg/kg, MAX 5mg total
onset: 1-5 min peak: 7-14 min
DOA: 30-60 min
AChE Inhibitors
-Neostigmine tips
-give with Glyco, similar onset
-give 0.2:1 glyco and neo
AChE Inhibitors
-Pyridostigmine dose
0.1-0.25mg/kg
-not used often
AChE Inhibitors increase ACh everywhere but we only want to stimulate the _ receptors and avoid _ action so we give anticholinergics with them
nicotinic (desired)
muscarinic (undesired effects)
Anticholinergic/ Antimuscarinics
Atropine dose + tip
7-15mcg/kg
-lipophilic, can cross BBB, placenta, and cause CNS s/e like hallucinations/sedation
Anticholinergic/Antimuscarinics
Glycopyrolate dose + tip
0.01-0.02mg/kg
Glyco gecko is tiny!
-better antisialagogue (antisaliva drug); ionized and won’t cross BBB
Suggamadex
-class + MOA
GAMMA CYCLODEXTRIN
-encapsulates amino steroidal MR and deactivates them (roc+vec)
Suggamadex
-A/E
Hypersensitivity
-rash,flushing,anaphylaxis
-happens IMMEDIATELY
-higher dose, higher risk
Arrhythmias
-BRADY, asystole
-emergency drugs! (ASO4 AKA Atropine(sulfate) !!!!)
Suggamadex
-dose
2,4,16
TOF dependent!
-No TOF twitches but PTC of 1-2= 4mg/kg (reverses in 3 min)
-TOF 2/4= 2mg/kg (reverses in 1-1.5min)
-After RSI Roc dose= 16mg/kg (reverses in 3 min)
Suggamadex
-tips
-do NOT need a anticholinergic
-can inhibit PO contraceptives!
Reversal speed depends on:
-depth of block
-type of AChE (edrophonium>Neo>Pyridostig)
-dose of AChE (too much ACh can cause DEPOLARIZING blockade)
-spont reversal and metabolism of NMBD
-conc of IA
Over reversal can cause a _ _ from excessive _ and _ effects
cholinergic crisis
nicotinic
muscarinic
Cholinergic Crisis
-s/s
-wet (secretions)
-bronchospasm
-resp paralysis (musc)
-BRADY (musc)
-diarrhea
-miosis (musc)
-muscle weakness / fasciculations (nicotinic)
Cholinergic Crisis
-diff dx from Myasthenic Crisis
similar s/s ; give EDROPHONIUM 2mg IV
-if Myasthenic crisis it should help, if it WORSENS, it’s cholinergic***
Cholinergic Crisis
-tx
-stop AChE inhibitor therapy
-make sure isnt Myasthenic
-give atropine
-resp support PRN
Signs of full reversal
-objective
-TOF = 4 twitches = 0-70% blocked
-TOFR > 0.7-0.9 is KEY*
-sustained tetanus 50-100Hz >5sec without fade = 0-70% blocked
-NIF >40cmH2O
-VC >20mL/kg
-Vt >5mL/kg
Signs of full reversal
-subjective
-5s head lift
-tongue purposeful movement
-strong hand grip
-spont breathing with good Vt (not super reliabe)
-RR smooth
-eye open on command
-+cough, swallow, bite, arm lift
-LOC ok
Why would spont breathing and good Vt NOT be a clear sign of full reversal?
Bc diaphragm movement returns before tongue or airway reflexes! (ability to protect airway)
How to pvn my pt from waking up in pain?
Time narc carefully
-LA narcs in maintenance phase
-SA narcs titrated to RR
-use doses ok for AWAKE pt
Multimodal anesthesia/ pain control
Regional options
How to pvn my pt from vomiting?
-impact of vomiting
Common cause of unplanned admission
-aspiration
-altered lytes
-dehydration
-BLEEDING from wound
-wound DEHISCENCE (from retching)
How to pvn my pt from vomiting?
- pt risk factors
Pt
-intraabdominal disease
-full stomach
-NONsmoker
-young, female
-HX OF PONV
How to pvn pt from vomiting?
-Surg +Misc contributing risk factors
Surgery
-eye, neuro, neck, ENT
-duration
Misc
-postop pain
-N2O
-opioids
-AChE (opt for suggamadex instead*)
-hypoxemia
-Hypotension
How to pvn pt from vomiting?
-Dexamethasone dose + timing
4mg PRE incision
How to pvn pt from vomiting?
-Ondansetron dose + timing
4mg PRE induction or 30 min PRE emergence
How to pvn pt from vomiting?
-Droperidol dose
0.625-1.25mg/kg
How to pvn pt from vomiting?
-propofol dose + timing
20-30mg close to emergence
How to pvn pt from vomiting?
-Benadryl dose
12.5mg IV
Global criteria extubation
-CV stable
-temp ok
-airway patent/reflexes present/ LOC ok
-muscle strength ok (reversed, TOF>0.9, tetanic response 100Hz 5s, DBS w/o fade)
-head lift +5s, strong grip
-lytes + acid/base ok
-not bleeding
-pain managed
-Hgb ok
Respiratory criteria extubation
-Vt 4-5mL/kg - IBW??
-VC >15mL/kg
-NIF > -20cm H2O
-SpO2 and pO2 ok with <50%FiO2
-PaCO2 <50mmHg
-spont RR/Vt ration <100breaths/min/L***
Awake Extubation
-indications
-pt at risk aspiration
-diff AIRWAY (AWAKE INTUBATION)
-tracheal or maxillofacial surg
-NGT (asp risk)
Awake Extubation
-clinical criteria
-laryngeal reflexes +
-awake
-CV stable
-fully reversed (TOF, sustained tetanus 50Hz for 5s
-+head lift, follows commands
-Spont breaths w/ good Vt (>5mL/kg)
-RR>8 but <30
Awake Extubation
-steps
-place OPA
-100% FiO2
-suction
-mild + pressure (20cm H2O to ETT)
-ETT cuff deflated, pull tube
-100% O2 face mask
-after pulling tube gently try to bag pt to see if ventilating, not having a spasm
Deep Extubation
-indications
-severe ASTHMATICS
-open eye, inguinal hernia /abdominal, breast red/implants cases (want to avoid pressure on site)
-pts who should avoid CV instability from extubation
Deep Extubation
-CI
-difficult MASK airway
-diff intubation
-aspiration risk
-surg could cause airway edema
-risks often > benfits
Deep extubation
-criteria
laryngeal reflexes MUST be suppressed
> 1 MAC surgical depth must be used to avoid airway stim
Deep Extubation
-steps
-have all tools needed for reintubation
-place OPA (will likely obstruct)
-spont breathing pt, RR + Vt must be good
-pt must be totally reversed
-suction
-deflate cuff
-if NO reaction to cuff deflation, pull tube
-if pt coughing DO NOT pull tube yet (laryngospasm risk)
-emerge pt via mask, finish like mask case until they no longer need support
Deep Extubation
-pros
-looks smooth
-less CV instability
Deep Extubation
-cons
obstruction and asp still possible
How to tell if pt is in stage 2?
-LOOK AT EYES (IF ROLLED BACK/LOOKING DOWN AT NOSE STILL IN 2)
-pupils dilated, divergent
- agitation, delirium, irreg RR, BREATH HOLDING
Risks of extubating in stage 2?
-vomiting/aspiration
-LARYNGOspasm
-HTN +tachy
-uncontrolled movement
When is pt ready to wake?
-is surg done?
-CV changes? (high HR/BP_
-return of reflexes (swallow, lid, glabellar [tap in between eyebrows-should blink])
-call name if reflexes return
How to awake extubate and avoid bucking?
-bucking is reflexive and narcotics can blunt this
-can also hyperventilate to dull drive to breath against vent
-LTA to numb cords
-awake pts on narcs will breathe, just tell them to
Trad wake up method
-Pros
-smooth, ok analgesia, comforting
Trad wake up method
-cons
-requires pt breathing
-slow, hypoventilating pt will blow off IA slowly
-increased SE of narcs
Trad wake up method
-steps
-reverse NMBD
-lighten IA
-increase EtCO2
-return to spont breathing
-titrate narcs
-extubate when pt awake + following commands
15/15 wake up method
-pros
-fast, smooth emergence if timed right
15/15 wake up method
-cons
-postop pain mgmt might not be optimal
-over or underdose of narcs to RR
15/15 wake up method
-steps
-reverse NMBD
-turn down IA
-dose narcs on lighter side
-15L FGF and 15 RR**
-hyperventilate gas off
-extubate when pt awake, following commands
Crash wake up method
-pro
-fast emergence when unprepared
Crash wake up method
-cons
-not nice, assault on nipps?!, painful >:(
Crash Wake up method
-steps
-fully reverse NMBD
-15L FGF, 15 RR
-hyperventilate, blow gas off
-naloxone
-PINCH NIPPS?!
-jaw thrust
-extubate when awake + following commands
What happens when surgeon starts closing?
-start backing down on IA
-can start giving N2O to replace some of MAC you gave
-EXCEPT WHEN OPEN BELLY
What happens when surgeon is closing skin?
-Turn off IA and N2O, wash out circuit with 8-10L FGF O2
-100%FiO2
-put in OPA
When do I give reversal in closing process?
-depends on peak effects, timing of case (how long will dressing take)
-am i positioned at HOB?
Surg is done, dressing is on, drapes are down, now what?
-adjust vent (bag vs vent)
-suction
-check for extubation criteria
-apply mild positive pressure (20cmH2O) on ETT
-ETT cuff deflated and pull tube -watch for spasm
-100% O2 via face mask
-deliver gentle breath to ensure ventilation and no spasm
-let pos pressure up gradually and pt will breathe without help ~5 breaths
-put on NC
-prep for PACU tx
Travelling to PACU
-monitor respirations en route, hand on face to feel air movement?
-can put kids on side if PONV risk
I’m in PACU now what?
-first give supp O2
-put on pulseox
-give pain meds if needed
-shivering is common, have blankets ready, be ready to increase O2
“Pt is tight I need longer to close or I’m letting med student close”
-ED95 of MR is usually 1/3 intubation dose but try to avoid
-benzo, prop1mg/kg (not full ind dose), lido 1-1.5mg/kg
-could increase IA conc
-N2O
-TALK TO SURGERY STAFF
“He’s waking up crazy”
-relax, first think of potential causes
first rule out hypercarbia/hypoxia, pain, hypotension, full bladder
-don’t mistake agitation for pain and medicate that
“He’s waking up crazy”
-Stage II wake up
-DONT PULL ETT (unless they already did)
-REDOSE PROP (HIGH DOSE)
-fentanyl
-droperidol
-stay away from benzos
-if biting tube = sux
Pt stopped breathing after I removed ETT… I ruled out laryngospasm and pt appears apneic
-actions
-try to vent off residual gas and stimulate, permissive CO2 to increase drive
-maybe needs narcan, suggamadex?
-prepare to intubate PRN
Pt stopped breathing after I removed ETT… pt is NOT apneic but chest is rocking boat trying to breathe (laryngospasm)
-next steps
put pt on sustained PPV and sux
-be ready to intubate PRN
Idk if my pt is ok after emergence, can I leave to get help?
Nope! It’s you babe, CALL for help but stay w pt
Pt not waking up…causes?
-R/O: hypercarbia, hypoxia, low BP
-intoxicated?
-poor reversal
-pseudocholinesterase deficiency?*
-hypo/er Na+
-hypo/er glycemia
-hypoTHERMIC?**
-CVA?
If pt not waking up during emergence and I know its bc of muscle relaxers, can I give reversal?
NO, put pt to sleep. Don’t wake pt up paralyzed!
Laryngospasm happen from stim of which nerve?
SLN internal branch!
Laryngospasm happen from action of which nerve/s?
SLN external branch and RLN
LAryngospasm is often triggered by secretions, surg plane, blood
-suction
What is the most common cause of post-obstructive pulm edema?
LAryngospasm
Ways to pvn laryngospasm?
-meds
-sevo
-LTA for cords
Laryngospasm
-tx
-GET HELP
-continuous + pressure with 100%O2 mask or circuit
-avoid unnecessary upper airway stim
-LARSON MANEUVER (middle finger between post border of mandible +mastoid to displace mandible forward, press HARD)
-if persists or SpO2 drop, propofol 1-2mg/kg
-if persisting give sux 0.2-2mg/kg
-maybe atropine PRN
Can you intubate a pt who is laryngospasming?
NO
Post-Obstructive Pulm Edema is AKA
Neg Pressure Pulm Edema
Post Obstructive pulm edema happens most often from:
Laryngospasm (or biting ETT/LMA)
-more common in young men
Post Obstructive Pulm Edema
-s/s
dyspnea
agitation
cough
PINK FROTHY SPUTUM
low sats
CXR: BL diffuse opacities
Post Obstructive Pulm Edema
-Patho
Happens from inspiration AGAINST obstruction
-DECREASES intrathoracic pressure
-INCREASES venous return
-INCREASES pulm blood flow
-INCREASES hydrostatic pressure
-transudation from capillary bed to interstitium***
-fluid is pulled into alveoli (pink + frothy)
Post Obstructive Pulm Edema
-tx
-relieve obstruction
-100% face mask(or CPAP)
-sit pt UP
-if fulminant pulm edema with critical hypoxemia, may need to intubate(keep inpt)
-IV opioids reduce subjective dyspnea
Upper airway reflexes maintain _ and upper airway _.
tone + patency
Laryngeal reflexes protect the _ airway
LOWER
Why does obstruction potentially cause aspiration?
forceful insp effort creates negative intrathoracic pressure
-pulls open esophagus and increase risk of regurg
Paradoxical VC motion
-risks
-diff dx
-patho
-tx
-young women
-could be mistaken as laryngo/bronchospasm
-VC adduction on inspiration sounds like stridor after extubation
-Tx with anxiolytics, sedation, opioids
