Perioperative Complications Flashcards
Perioperative complications include (11):
SSHHHH!!!
MOPP B
- sinus tach
- sinus brady
- hypotension
- hypertension
- hypoxia
- hypercarbia
- myocardial ischemia
- oliguria
- bronchospasm
- pulmonary aspiration
- pulmonary edema
_______ is the most common dysrhythmia. It is defined as HR _____ w/ normal P wave.
Sinus tach
>100 bpm w/ normal P wave
Causes of sinus tachycardia include:
1) increased _____ ______ ______
2) reflex response to ______ or _______
3) ______ or _____
4) ______ ______
5) ________
6) Medications
7) ________
1 - endogenous catecholamine release 2 - hypotension or hypovolemia 3 - fever or MH 4 - pulmonary embolus 5 - pheochromocytoma 7 - thyrotoxicosis
The following cause increased endogenous catecholamine release:
- preoperative ______
- surgical _____ from incision
- __ and _____ intubation
- ____/____ stimuli
- _______ anesthetic depth
- h_____
- h________
- excessive _____ inflation time
- e________
anxiety stimulation DL and trachea noxious/painful inadequate hypoxia hypercarbia tourniquet emergence
Medications that can cause sinus tachycardia include:
1) Vagolytics such as _______ used for NMB reversal and antisialagogue effects.
2) _______
3) Muscle relaxants - specifically ______
4) ______ anesthetics (______ initial rapid uptake)
1 - antimuscarinics
2 - sympathomimetics
3 - pancuronium
4 - volatile - desflurance
Treatment for Sinus Tach:
1) Verify tachycardia isn’t artifact or ESU interference (check ___________)
2) Determine and treat underlying cause! (Don’t just give esomolol….)
3) Ensure adequate ______ and ______
4) Adequate ____ _____
5) Correct ______ or ______
6) Pharmacological Management:
- _____
- ______ to buy time
- Preop ______
- ______ (rarely)
**a lot of times if the patient is deep + tachycardia, it is d/t ____ _____& typically corrects w/ ____
1- pulse ox waveform 3 - oxygenation, ventilation 4 - anesthetic depth 5 - hypovolemia, hypotension 6 - opioids, beta adrenergic blockers, anxiolysis, CCBs
**a lot of times if the patient is deep + tachycardia, it is d/t fluid deficit & typically corrects w/ bolus
Sinus bradycardia is defined as HR < ____ BPM w/ normal P wave. It is ______ in young health patients and usually does NOT require treatment if ______ _______.
Rarely, it can deteriorate to sinus arrest.
<60 BPM
common
hemodynamically asymptomatic
**if BP is good and HR is 40 - do NOT mess w/ it
Sinus bradycardia can be caused by:
1) ______ response to surgical manipulation
2) High level _____ _____ (_____ anesthesia)
3) ______ nerve stimulation
4) _____ anesthetics
5) ______ in neonates and children
6) Medications
1 - vagal
2 - sympathetic block - neuraxial anesthesia
3 - trigeminal
4 - volatiles (halothane, sevoflurane)
5 - hypoxia (in children causes bradycardia, adults is tachycardia)
High level sympathetic blocks (neuraxial) blocks effect ________ fibers (T1-T5) and results in increased predominance of ______ response mediated by the _____ and results in sinus bradycardia.
cardio-accelerator
PSNS
vagus
Trigeminal nerve stimulation used in ______ ______ can cause bradycardia. Pretreat w/ ______ to prevent the huge PNS outflow.
electroconvulsive therapy
Robinul
Drugs commonly used during anesthesia can cause bradycardia:
- Narcotics such as _____ and _____
- Alpha 1 agonists (______)
- ________ muscle relaxants
- Reversal agents such as _______
fentanyl, alfentanil
phenylephrine (squeezes and lowers HR)
depolarizing (Succinylcholine - usually on 2nd dose - mimics ACh)
neostigmine
Treatment of sinus bradycardia includes:
1) May NOT require Rx if ______ ____
2) Maintain ______ and ______
3) May require _______ depth of anesthesia
4) Remove/extinguish ____ ______
5) _________ (Atropine or Robinul)
6) ________ agents (Isoproterenol)
7) ____ ______ (rarely utilized)
1 - hemodynamically stable 2 - oxygenation, ventilation 3 - decreasing 4 - vagal stimulus 5 - antimuscarinics 6 - chronotropic agents 7 - cardiac pacing
vagal response to surgical manipulation can cause bradycardia.
Examples include:
- ____ manipulation
- Abdominal _____
- _____ stimulation (cervix)
- ____ _____ traction
- ____ surgery or retractor use or stimulation
- Tracheal ______ or ______ (CAN cause vagal response)
- ______ laryngoscopy
- Ophthalmic surgery, optic pressure, or traction of extraocular muscles
Bowel insufflation Peritoneum Lumbar spine Neck intubation or extubation Direct
Ophthalmic surgery optic pressure or traction of extraocular muscles can cause a vagal response. It involves the ______ reflex arc - _______ trigeminal and _____ vagus.
The oculocardiac reflex produces ______ in 90% of patients.
______ increases the OC reflex.
Antimuscarinics such as atropine do NOT ______ the reflex.
trigeminovagal
afferent trigeminal
effect vagus
bradycardia
hypercarbia
prevent
**best thing to do is to tell the surgeon to stop pulling on the eye muscles
The second most common intraoperative complication is _______.
hypotension
Causes of hypotension can include:
1) BP measurement _____
2) Lack of or decreased magnitude of _____ _____
3) Decreased _______
4) Decreased _____
5) Decreased ____ _____
6) ______ response to surgical stimulation
7) _______
1 - error 2 - surgical stimulation (decreased SNS activity/catecholamines - may need gtt until surgery starts) 3 - contractility 4 - SVR 5 - venous return 6 - vasovagal response 7 - dysrhythmias
BP measurement error resulting in a hypotensive reading can be caused by:
- transducer height or calibration error
- ______ invasive system
- limb cuff _____, _____, or improperly fitting
overdamped
oversize, loose
Decreased contractility can result in hypotension and can be caused by:
1) _____ agents
2) _____
3) cardiac meds such as ____ _____
4) cardiac dysfunction such as _____, _____ imbalance, acidosis or alkalosis, or ____thermia.
1 - volatile
2 - opioids
3 - beta blockers
4 - ischemia, electrolyte, hypothermia
Decreased SVR can result in hypotension and can be caused by:
- _____ anesthetics
- ______
- ________
- various other drugs administered during anesthesia
- ______ outflow blockade such as w/ ____ ______
- increased ______ tone
- ______
- vasoactive metabolites (____ _____ and _____ _____)
- allergic reactions d/t increased ______ release
- _______
- volatiles
- opioids
- benzos (all 3 work synergistically)
- sympathetic blockade (neuraxial)
- parasympathetic tone
- sepsis
- tourniquet release (metabolite release works as massive vasodilators) & anaerobic respiration
- histamine
- hypoxemia
Decreased venous return can result in hypotension and can be caused by:
1) _______ d/t fasting, bowel prep, vomiting/diarrhea, acute hemorrhage, diuretic therapy or HTN-induced diuresis
2) Vena cava ______ or _____ use
3) Increased _____ _____/______
4) Increased ______ _____ d/t PEEP, excessive Vt
5) _______ and ____ ______
6) Dramatic ____ _____
*Decreased venous return leads to decreased stroke volume and ultimately decreased CO.
1 - hypovolemia 2 - compression, retractor 3 - venous capacitance, pooling of blood 4 - intrathoracic pressure 5 - pneumothorax and cardiac tamponade 6 - position changes
The vasovagal response to surgical stimulation results in decreased ____, ____, and hypotension.
SVR, HR
Dysrhythmias can cause ______ and include tachyarrhythmias, AF, AFlutter (reduced ventricular filling & no atrial kick w/ 30% less SV), and bradyarrhythmias.
hypotension
Treatment for Perioperative Hypotension:
1) FIRST _____ _____ - treat the patient not the monitor.
2) Ensure measurement is not erroneous.
- Check transducer calibration and assess damping
- Confirm appropriate cuff size and fitting
- Palpate and assess peripheral pulses
- Assess any acute pulse oximetry waveform changes
- Assess any acute capnography waveform changes such as _____ ETCO2.
- Confirm adequate oxygenation and ventilation
3) Determine and treat underlying cause.
4) ______ expansion, restore _____ status w/ _____.
5) ______ anesthetic depth or _____ opioid use if able.
6) ______ or place in _______
7) Consider ______ in patients prone to hypotension.
8) Vasopressors including ______ and/or ______
9) Treat dysrhythmias w/ _____ or antidysrhythmics
10) Reduce _____ or ______ (may require increased rate)
11) Chest tube placement or pericardiocentesis
1 - retake BP! 2 - decreased ETCO2 - if reading is low and ETCO2 also drops, the BP reading is probably accurate 4 - volume, fluid w/ bolus 5 - lighten, reduce opioids 6 - reposition, trendelenburg 7 - Ketamine 8 - sympathomimetics, inotropes 9 - vagolytics 10 - Vt or PEEP
If you have to lighten the anesthetic depth or reduce opioids to treat hypotension, it may be necessary to apply an _______ monitor. You will also need to increase ______ to ensure motionless.
awareness
paralysis
** Granny in for a trauma, can’t support BP, turn down anesthetic to 0.5 MAC - risk pt. being aware.
Hypotensive and worried about anesthetic depth - give ketamine.
Nitrous can also cause brief SNS output.
Ketamine can be used in patients prone to hypotension b/c it increases ____ outflow. It causes increased ___ and _____ (SBP increases 20-40 mmHg in <5 minutes).
This can be beneficial in trauma patients but have the potential to unmask the mild ______ ______ effects in patients with depleted ________ stores. Also not good for elderly debilitated patients with poor compensatory CV ability.
SNS
HR and vasoconstriction
myocardial depressant
catecholamine
Postoperative HTN incidence is 6-20% and commonly d/t _____.
- 30-80% reported following CABG
- Risk factors for developing post-op HTN include:
1) increased ____, _____, & _____ disease
2) inadequate _____
3) Preop h/o _____
4) Preop h/o _____
pain
increased age, smoking, renal disease
ventilation
hypertension
angina
Perioperative HTN can complicate surgical outcomes:
1) ______
2) _____ suture lines
3) ______
4) myocardial _____
5) _______
1 - hemorrhage 2 - ruptured 3 - CVA 4 - ischemia 5 - dysrhythmias
RICH D
Causes of perioperative HTN include:
1) Increased ______ release
2) H/o ______
3) Increased _____ _____
4) Systemic vasoconstrictor absorption of _____ or ______
5) Rebound HTN resulting from d/c of ___ ______
6) Distended _____
7) Aortic ____ _____
8) _____ _____ dye
9) Exaggerated drug effects d/t ______ use.
1 - catecholamine release 2 - HTN (pts. w/ h/o HTN also have increased risk for intraop hypotension - take ALL BP meds before except for lisinopril) 3 - intracranial pressure 4 - epi, phenylephrine 5 - BP meds 6 - bladder 7 - cross clamping 8 - indigo carmine 9 - MAOI use
Perioperative HTN Treatment:
1) Increase _____ – most common
2) IV ________
3) Preoperative _____
4) Evacuate urine from distended bladder
5) Beta blockers (3)
6) Vasodilators (3)
7) CCBs
8) ACEIs, angiotensin receptor blocker, alpha 1 blocker, alpha 2 agonist such as _______
1 - anesthetic depth 2 - opioid narcotics (fentanyl – but do not give right at end of case) 3 - anxiolysis 5 - labetalol, esomolol, metoprolol 6 - nipride, NTG (FAST), hydralazine 8 - alpha 2 agonist = Precedex
Hypoxia is reduced O2 tension (PaO2) at the _____ level.
There are 5 categories:
1) hypoxemia
2) anemic
3) circulatory
4) affinity
5) histiocystic
tissue
An oxyhemoglobin shift to the right means _____ unloading of O2 by Hgb to tissues. A shift left means ______ unloading of O2 to tissues for any given PO2.
right = easier left = more difficult
**easy to be right, hard to take a left
________ hypoxia: decreased blood oxygen tension & decreased PaO2 - can be caused by low FiO2, hypoventilation, V/Q mismatch (shunt), or diffusion limitations.
hypoxemia
______ hypoxia results from not enough Hgb.
- low hemoglobin concentration
- Hgb w/ decreased _____ for oxygen (abnormal Hgb)
Treatment: _______
ASA task force recommendations:
Rarely if Hgb > _____
Nearly always if Hgb < ____
anemic
affinity
transfusion of PRBCs
rarely if >10 gm/dL
always if <6 gm/dL
______ hypoxia results from not enough CO.
There IS adequate Hgb!
All conditions that reduce ___ and/or ____ will reduce CO - symptomatic bradycardia, hypovolemia, and reduced venous return.
It can also be caused by inadequate _____ over time - insufficient delivery (supply) to meet metabolic demands.
circulatory
HR and/or SV
volume
_______ hypoxia results from decreased release of O2.
affinity
_______ hypoxia: cell won’t accept the delivery of the O2 (ex: cyanide poisoning)
1) CO poisoning shifts oxyhgb curve to the _____: binds to cytochrome c and disrupts oxidative metabolic processes in the mitochondria. Correction requires O2 at 3 ATM (hyperbaric chamber).
2) Nipride can produce _____ toxicity. _____ binds to mitochondrial cytochrome oxidase disrupting aerobic metabolism and inhibits oxidative phosphorylation and prevents ATP synthesis.
histiocystic
1 - CO - LEFT
2 - cyanide, cyanide
Recognizing Hypoxia:
1) _____ blood in wound
2) Cyanotic mucous membranes is _____ & ____ ____.
- Absence of cyanosis does not mean the patient is ______.
- Cyanosis is a ____ ____ of hypoxia (oxyhgb saturation is usually <___% before cyanosis develops)
3) _____
4) _____ _____
1 - dark 2 - unreliable, late sign; - oxygenated; - late sign, <85% *12% of pts. w/ O2 sat between 71-80% were found to have normal skin color on assessment
3 - ABGs
4 - pulse ox
**remember, w/ anemic patients, cyanosis is hardly recognizable; w/ high Hct, cyanosis is exaggerated.
Hypoxia Management:
Determine the ______ (4 categories) & treat!
- Supplemental O2 - increase FiO2.
- Increase O2 _______ (inotropes, chronotropes)
- Correct V/Q mismatch - ____ or _____
- _____ ______
- Hyperbaric chamber for affinity hypoxia
CAUSE
1 - hypoxemia
2 - delivery - circulatory
3 - PEEP, VCM (hypoxemia)
4 - PRBCs (anemic)
Hypercarbia is defined as CO2 > ___ mmHg. This can cause ______ and _____ _____ - _____ and ______ can result.
> 90 mmHg
narcosis, additive MAC (CO2 narcosis makes you lethargic, diminishes brain function to some extent)
acidosis, hyperkalemia
**this w/ happen to some extent w/ almost every anesthetic - common w/ sedation cases d/t hypoventilation
Hypercarbia can be caused by:
1) Decreased CO2 ________ (most common)
2) Increased CO2 ________
elimination
production
Decreased CO2 ELIMINATION can be caused by:
- ________ (common)
- opioids, benzos, volatiles
- high neuraxial anesthesia
- residual NMB
- inadequate vent settings
- increased airway resistance
- increased ETCO2 rebreathing caused by LOW FLOW closed circuit or exhausted CO2 absorption
- increase in dead space ventilation, PEEP, circuit, pulmonary embolus
hypoventilation
very common w/ sedation cases
Increased CO2 PRODUCTION can be caused by:
________ states such as hyperthyroid, pheochromocytoma, hyperthermia, CO2 abdominal insufflation, reperfusion, tourniquet release, shivering, and MH.
hypermetabolic
Recognizing Hypercarbia:
1) No return to zero baseline on ______
2) Increase in ____ outflow, _______, _____, _______, and restlessness
capnograph
SNS, HTN, hyperventilation, tachycardia
Management of Hypercarbia:
1) Increase _____ ______
2) ↓_____ ______ in spontaneous ventilating pts.
3) Use narcotic and benzodiazepine reversal agents (rare)
4) ↑ _____ ____ _____ or create open circuit system (2xVm)
5) Change ___ _____
6) Reduce ____ _____
1) Minute ventilation
2) decrease anesthetic level (Pt. will start to breathe faster and deeper)
4) fresh gas flow
5) CO2 absorber
6) dead space
Myocardial ischemia: it’s all about managing oxygen ____ and ______. The anesthetist has all of the tools to DETECT ischemia and manipulate both supply/demand.
STATS FYI:
- > 50,000 patients a year develop perioperative MI
- Mortality and morbidity are increased in patients who develop perioperative myocardial ischemia
- NO evidence that General better than Regional Anesthesia
supply
demand
Myocardial Oxygen Supply/Demand Imbalance:
Increased myocardial oxygen demand is of ____ ______ than decreased myocardial oxygen supply!
greater significance
**we can control demand more than anything by lowering HR and BP
**can have decreased supply d/t diastole shortening (increased HR)
Simultaneous _____ and ______ present the greatest risk to patients w/ a h/d ischemia heart disease as it causes _____ demand and _____ supply.
The WORST situation.
tachycardia
hypotension
increased demand, decreased supply
Population at Risk for MI:
1) MI w/in the last ___ months
2) ____ ____ ____
3) Previous h/o postop ____
4) ALL cardiac surgical patients have increased risk for ischemia. 40% develop ischemia preop & post op. 60% develop ischemia intraop.
1 - 6 mo
2 - CHF
3 - MI
Read Clinical Predictors of Increased Perioperative CV Risk on slide 34.
Will always perform preop EKG for those in the MAJOR category, possibly for those in the intermediate category, and rarely for those in the minor category.
Review Factors That Contribute to Myocardial Ischemia on Slide 35.
Read Intraoperative Events That Influence the Balance Between Myocardial Oxygen Delivery & Oxygen Requirements on slide 36.
Symptoms and altered hemodynamics are ______ indicators of myocardial ischemia. We can use TEE to detect abnormal regional wall motion. It is the MOST reliable and MOST accepted standard for detection of intraoperative myocardial ischemia.
- Abnormal regional wall motion occurs ____ to EKG changes.
- Widespread use is cost prohibitive.
unreliable
prior to
- *Most common method is telemetry
- *Most reliable method is TEE
PA Catheter monitoring is an ______ detector of ischemia.
- Acute _____ in PAWP indicative of ↓ LV compliance and performance.
- ___ waves in PAWP tracing may indicate ischemia.
- Limited use because PAWP are only taken intermittently.
unreliable
increase
V waves
____ is the most commonly utilized modality for detection of ischemia & is a standard of practice. Most perioperative myocardial ischemia and infarctions are ________:
- ST _____ >1 mm or T wave _____ = ________ ischemia
- ST elevation indicates _____ ischemia
EKG
SUBENDOCARDIAL
depression or T wave inversion = subendocardial
elevation = transmural
____ is the most sensitive lead for detecting perioperative myocardial ischemia. 75% of ischemic events are detected here.
Combining leads ___ and ___ resulted in detection of 85% of ischemia events
V5 - 75%
V4 + V5 - 85%
(3 leads are better)
Review Intraoperative Monitors for Ischemia on slide 40.
Proper 5-lead EKG placement can assist in early detection of ischemia.
1) 3 leads have been shown to improve detection of ischemia:
- Lead II: detect ____ ischemia - _____ wall supplied 90% of the time by ____
- Leads V4 & V5: detect ___ ischemia - bulk of LV supplied by _____
2) Monitors that display computerized ST segment analysis
Lead II: RCA ischemia, inferior wall supplied by RCA
Lead V4/V5: LV ischemia, supplied by LAD
Implications related to myocardial ischemia:
1) Minimize ______ and _______:
- maintain ___ and ___ w/in 20% of baseline
- Chronic HTN patients are usually ____ ______ and their autoregulation curve is shifted to the ____
2) Continue ____ ____ therapy if the patient is currently being treated w/ one.
3) Avoid _______: hypocarbia may lead to coronary _____/______.
4) Minimize ____ stimulation - pain, hypercarbia, hypovolemia.
5) Maintain normal blood oxygen content w/ _____ patients: closely monitor excessive blood loss resulting in decreased Hgb.
6) ____ extubation if possible & if extubation criteria is met.
7) Avoid intraoperative ______.
8) Utilization of muscle relaxants that do not effect HR (3)
9) NMB reversal w/ antimuscarinics w/ less chronotropic effects (i.e. ______)
10) Short during _____ _______
11) Avoid induction w/ ________.
12) Optimize myocardial supply & demand!
1 - hypotension, HTN; BP, HR; volume depleted, right
2 - beta blocker
3 - hyperventilation - vasoconstriction/spasm
4 - SNS
5 - CAD
6 - early/deep extubation (increased HR/BP on emergence can lead to increased ischemia - avoid bucking/coughing)
7 - hypothermia (shivering can increase VO2 600% - normothermia can reduce perop ischemia and subsequent cardiac mortaltiy)
8 - vecuronium, rocuronium, cisatracurium (pancruonium can increase HR and contribute to ischemia)
9 - use glycopyrrolate instead of atropine
10 - direct laryngoscopy (<15 seconds) (can use videolaryngoscopy) **LTA, IV lidocaine, fentanyl, esmolol - have all been shown to blunt the SNS response and the increase in HR associated w/ intubation
11 - ketamine: increases HR, BP, and myocardial O2 requirements
(info from slides 41-47)
Optimizing myocardial oxygen supply & demand:
Volatile anesthetics:
- _____ myocardial O2 requirements
- _______ myocardium to tolerate ischemic events in presence of decreased SBP and decrease coronary perfusion pressure
- no evidence that ______ induced decrease in coronary vascular resistance leads to coronary steal.
AVOID _______ > ____
volatiles: decrease O2 requirements, precondition, isoflurane
avoid tachycardia >80 bpm
Review Flow Chart on Slide 48.
surgery=> inflammatory & neuroendocrine stress response => preoperative myocardial injury /infarction
Sympathomimetics for Ischemia:
1) Sympathomimetics to treat ______ - restores and maintains CPP
2) _____ support when hemodynamically unstable - ischemia reduces CO and causes hypotension.
3) ____ _____ agonists: can be useful to _____ LVEDV and ______ aortic diastolic pressure but can be harmful by ____ HR, ____ diastolic time, and _____ contractility.
1) hypotension
2) ionotropic support
3) beta adrenergic agonists - GOOD: decrease LVEDV, increase aortic diastolic pressure; BAD: increase HR, decrease time, increase contractility
**Problem w/ giving sympathomimetics: we want HR down, we want a little pressure – cautiously treat, too much and we can increase afterload too much (increase workload), too little and not enough pressure to perfuse coronary pressure
Alpha 1 adrenergic agonists _____ myocardial oxygen supply by _____ aortic diastolic pressure.
However, its detrimental effects include _____ myocardial O2 demand and coronary ______.
increase O2 supply by increase aortic diastolic pressure
increase O2 demand (arterial pressure increase associated w/ 60% increase in myocardial O2 consumption) &
coronary vasoconstriction
Alpha 2 agonists can ____ SNS outflow and _____ HR/BP.
decrease, decrease
ex: precedex
Nitrates & Ischemia
1) Nitroglycerin (NTG) is utilized when ischemia is accompanied by ____ _____. It causes coronary _______ and decreases _______ to improve subendocardial blood flow.
2) Nipride is much like NTG but with _____ reduction. It has controversial use in myocardial ischemia - possible coronary steal.
high BP
vasodilation
decreases preload
afterload reduction
Beta blockers have mixed research regarding reduction in post-op mortality.
They decrease myocardial _____ and increase ______.
They decrease ____ and ______ but may cause cardiac depression. Controversy exists regarding most appropriate use.
decrease demand, increase supply
decrease HR & contractility
Calcium channel blockers _____ myocardial O2 demand and _____ supply. They are shown to reduce coronary artery _______.
decrease demand, increase supply
vasospasm
Phosphodiesterase Inhibitors cause systemic and pulmonary ______ without an increase in ____.
vasodilation
HR
Review Management of Myocardial Ischemia on slide 54.
Oliguria is a common perioperative complication and is defined as UOP < ____ mL/kg/hr.
Causes:
1) _____: decreased CO, renal perfusion, fluid volume
2) _____: ATN, glomerulonephritis, toxins
3) _____: obstructive, stones, prostate, neurogenic bladder, catheter obstruction
<0.5 mL/kg/hr
prerenal (may need phenylephrine to increase BP = increase UOP)
intrarenal
postrenal
pre_ decreased corp fv
intra gat
post spon. boc
Management of Oliguria:
1) R/o mechanical obstruction such as blocked foley
2) Restore ______: correct hypotension, increase CO - possible low dose dopamine infusion
3) Correct ____ _____ deficit: crystalloids, colloids
4) Intraoperative diuretics: Lasix __-__ mg IV or ______
2 - perfusion
3 - fluid volume
4 - 2-20 mg, mannitol (rarely have to do this)
Bronchospasm is extreme bronchial constriction in which both LARGE and SMALL airways constrict. It can be triggered by “tracheal” instrumentation. ____ _____ is the most common cause of bronchospasm.
It results in very little air movement and thus very little ___ _______.
_____ is DRAMATICALLY reduced. Elimination of ______ is SIGNIFICANTLY reduced. Basically like a plug in the ETT.
tracheal intubation
gas exchange
ventilation
ETCO2 elimination
***use LMA if at risk for bronchospasm - doesn’t go in trachea/bronchi
Bronchospasms are rare (2%) but wheezing is common. It is mediated by the _______ nervous system.
It is more common in chronic _____ and ______ w/ REACTIVE airways and patients w/ _____ histories.
Adult triggers: mechanical or noxious ____ ______
Pediatric triggers: ______ _____ and recent ______ or ______
Other triggers:
- _____-releasing drugs such as morphine, atricurium
- anaphylactoid and transfusion reactions
parasympathetic (bronchoconstriction)
bronchitis, asthmatics, smoking
adults: chemical/mechanical irritants
peds: environment allergens, viral resp. illness or URIs
histamine
Review Causes of Acute Bronchospasm in Anesthetized Patients on slide 58.
Predicting acute bronchospasm:
1) FEV1 less than ___-___% of predicted value.
2) Starts w/ wheezing > tachypnea/dyspnea in awake patients > prolonged expiration > decreased breath sounds > increased airway resistance > increased PiPs in vented patients > _____ ______ > decreased O2 sat > decreased ______> increased intrathoracic pressure d/t air trapping > decreased venous return & CO > hypotension!
FEV1 <30-50% of predicted
difficulty ventilating
decreased ETCO2
Clinical Signs of Bronchospasm:
1) Very high peak airway pressures, difficult to _____ _____!
2) No ____ ____ b/c everything is totally clamped down
3) No ______ waveform (thinking esophageal intubation)
4) Very distant breath sounds almost ___-______.
5) Many will extubate and attempt to reintubate b/c SpO2 will drop & no real evidence of a confirmed endotracheal intubation (reintubation results in same result).
manually bag
tube fog
ETCO2 waveform
non-existent
Treatment of Bronchospasm:
1) Avoid airway _______ (___) - use LMA or regional
2) Avoid _____-releasing drugs, _____, and ____ _____
3) ______ ______ level (MOST important factor): _____ is better than thiopental and etomidate. ____ has bronchodilator effects and increases catecholamines.
1 - instrumentation (ETT)
2 - histamine, NSAIDS, beta 2 blockers
3 - DEEPEN ANESTHETIC LEVEL - propofol better; ketamine
Pharmacology solutions for bronchospasm and RAD:
1) IV _____ and _____ help to blunt airway reflexes
2) Increase _______
3) Perioperative _____ such as _____
4) _______ such as Robinul or atropine
5) Corticosteroids: ______ ___ mg IV
6) Epinephrine __-__ mg IV
1 - opioids, lidocaine 2 - FiO2 3 - bronchodilator (albuterol) 4 - antimuscarinics 5 - solumedrol 125 mg IV 6 - epi 0.1-1 mg IV
Review Causes of Non-bronchospastic Wheezing in Anesthetized Patients on slide 63.
Pulmonary aspiration occurs when depressed/absent airway reflexes cannot protect the trachea. It occurs in 1-10:10,000 anesthetics.
Average hospital stay is 21 days with a 5% mortality rate.
____ aspirate can damage alveoli in 12-18 seconds!
Effects: pH <____ and volume > ____ mL/kg can cause alveolar _____, collapse, edema, increased airway resistance, hypoxia, obstruction (large particles), and inflammatory response.
acidic
pH<2.5
>0.4 mL/kg
hemorrhage
Populations at risk for Pulmonary Aspiration:
- extreme age
- emergency/trauma
- hiatal hernia
- GERD
- morbid obesity
- full stomach or decreased NPO time
- pregnancy
- diabetes (full stomach)
- neuromuscular diseases
- GI tract diseases
- AMS
- small bowel obstruction
- increased ______
- h/o N/V
- ____ use (can cause gastric distention + unprotected airway and decreased reflexes = aspiration risk)
pain
LMA use
Pulmonary Aspiration Recognition:
90% have symptoms w/in ___ hour.
If awake: coughing, cyanosis, wheezing (40%), tachypnea, rales
If anesthetized: _____, ______, wheezing, increased PiPs, decreased ____, ____, and ____.
CXR may detect pulmonary infiltrates - delayed 6-24 hours.
1 hour
laryngospasm, bronchospasm
decreased BP, VR, and O2 sat (decreased O2 sat in <30 sec)
Pulmonary Aspiration Management:
1) IV PPIs, H2 antagonists, prokinetics, PO antacids, antiemetics _______
2) Turn head to the ____ to prevent aspirate from falling into trachea
3) ____ for patients at risk for aspiration
4) Immediate _____ and _____
5) Take control of airway in severe cases - ____ _____
6) Administer ____ and adequate ______
7) Can give antibiotics, steroids, bronchodilators, Lasix to help remove fluid off of lungs.
8) ______ may be indicated for removal of large particles obstructing airway.
1 - preoperatively 2 - side 3 - RSI 4 - suction, 100% FiO2 5 - tracheal intubation 6 - PEEP, Vt 8 - bronchoscopy
Pulmonary _____ can be causes by cardiac valve disease, ischemia, fluid overload, increased pulmonary capillary permeability, neg. pressure pulm. edema, and hypoxia-induced catecholamines (increased PVR & SVR).
S/s include copious ___ ____ fluid w/ _____ and ______, forceful coughing, and CXR is _____.
Treat w/ _____, O2, vaso_____, and mechanical ventilation w/ _____.
EDEMA
pink frothy, bubbles, hemoptysis
WHITE CXR
diuretic, vasodilator, PEEP
Ketamine can be used in patients prone to hypotension b/c it increases ____ outflow. It causes increased ___ and _____ (SBP increases 20-40 mmHg in <5 minutes).
This can be beneficial in trauma patients but have the potential to unmask the mild ______ ______ effects in patients with depleted ________ stores. Also not good for elderly debilitated patients with poor compensatory CV ability.
SNS
HR and vasoconstriction
myocardial depressant
catecholamine
