Things to Know Flashcards
1
Q
Which EKG Lead is best for monitoring ischemia
A
V5
Lead V5 alone will detect 75% of ischemic episodes in men 40 – 60 years of age, adding lead V4 increases this to 90%, and the combination of leads II, V4, and V5 add up to a 96% detection rate
2
Q
Which EKG Lead is best for monitoring for arrhythmia
A
II
3
Q
What is HELLP Syndrome
A
Hemolysis, Elevated Liver enzymes, Low Platelets
Signs & Symptoms
1) RUQ pain or epigastric pain
2) HTN
3) Headache
4) N/V
5) Proteinuria
4
Q
Pre-Eclampsia Definition
A
Pre-Eclampsia Definition
Mild
1. Two readings of SBP > 140 or DBP > 90, ideally 2 measurements at least 4 hrs apart
2. Proteinuria – 24 hr urine level > 300 mg or urine protein/cr ratio of 0.3
3. > 20 weeks gestation
5
Q
Severe Pre-Eclampsia (severe features)
A
- Sustained SBP > 160 or DBP > 110 (ideally 2 measurements 4 hrs apart)
- New renal insufficiency (Cr > 1.1 or doubling of Cr)
- New CNS disturbances i.e headache or vision changes
- Pulmonary edema
- Liver dysfunction (LFTs doubling)
- Epigastric or RUQ pain (distention of Glisson’s capsule)
- Thrombocytopenia < 100,000
6
Q
Age of gestation to need Mg for neuroprotection
A
24-32 weeks
7
Q
Steroids for fetal lung maturity
A
One course of antenatal corticosteroids should be administered to all patients who are between 24 and 34 weeks of gestation and at risk of delivery within 7 days
8
Q
Affects of maternal magnesium
A
Seizure prophylaxis, decreased SVR, increased uteroplacental perfusion
Complications: muscle weakness, respiratory & CV depression
9
Q
Neonatal resuscitation
A
MOM IS PRIMARY PATIENT MAKE SURE MOM IS BEING TAKEN CARE OF
1) Assess neonate for term, tone, breathing
2) Clear the airway
3) Warm, dry, stimulate
4) Supplemental oxygen as needed to maintain target SpO2
If following above HR was below 100 or remained apneic and gasping
5) Provide PPV starting with room air then titrating upwards
6) Place SpO2 on RUE, consider placing EKG
After 30 seconds if HR less than 60
7) Intubate
8) Begin chest compressions at 3:1 rate with breaths
9) Establish IV access - Umbilical vs. IO
10) Place EKG if not already placed
If after 60 seconds HR remains < 60 bpm
11) Administer 0.01-0.03 mg/kg epi
12) Give fluid or blood if hypovolemic
13) Eval for possible pneumothorax, hypoglycemia, magnesium toxicity
10
Q
Neonatal target O2 Sat
A
1 min - 60-65%
2 min - 65-70%
etc up to 10 min 85-95%
11
Q
Heparin dose for CBP
A
300 U/KG (about 21,000 units in a 70kg man)
12
Q
SVR calculation
A
SVR = [(MAP - CVP)/CO]*80
MAP: Mean Arterial Pressure
CVP: Central Venous Pressure
CO: Cardiac Output
Normal 750-1200
13
Q
PVR calculation
A
PVR = [PAP-PCWP/CO]*80
Normal 100-200
14
Q
Treatment for uterine atony
A
Reduce inhalational agent first if GA
1) Oxytocin
2) Methergine (methylgonovine) 0.2 mg IM
3) Hemabate/Carboprost - 15-methyl-prostaglandin F2-alpha 250 mcg IM
3) Misoprostol (cytotec, prostaglandin E1 analogue), 400 mcg sublingual or 800 mcg-1000mcg per rectum
4) Dinoprostone (prostaglandin E2) - 20 mg vaginal or rectal
If none of the above working consider: Intra-uterine balloon B-lynch sutures Ligation of internal iliac, uterine and ovarian arteries Hysterectomy
15
Q
Oxytocin, Methergine, Hemabate - how do they work and any contra-indications
A
All work by contracting myometrial smooth muscle by increasing intracellular calcium levels
Hemabate - associated with bronchospasm
Methergine - associated with HTN
Oxytocin - associated with hypotension
16
Q
Rule of thumb for what PaO2 should be for a certain FiO2
A
FiO2 x4-5
17
Q
Sevoflurane vs. Desflurane vaporizer type
A
Sevoflurane is a variable bypass vaporizer - variable amount of gas is directed into a vaporizing chamber
Des vaporizer electrically heats to create a vapor pressure of 2 atmospheres then pure des vapor is mixed with fresh gas
18
Q
PSI of full O2 tank
A
~2000 psi in full tank, about 660 liters O2
Time remaining (hrs) = Pressure (PSIG) / [200 x flow rate (L/min)]
19
Q
Sickle cell disease
A
Substitution of valine for glutamic acid in beta chains of hemoglobin leads to hemoglobin S (sub on chromosome 11)
Preoperative hematocrit of 30% for patients undergoing moderate and high risk surgeries
Treatment of sickle cell crisis: pain control, IV hydration, supplemental oxygen, maintaining hematocrit, treating infection, exchange transfusion to reduce fraction of Hfb S to less than 40%
20
Q
Risk factors for aspiration
A
obesity delayed gastric emptying (pain, acute abdomen, cirrhosis, chronic alcohol use, autonomic neuropathy) pregnancy neurologic dysphagia bowel obstruction disruption of the GE junction extremes of age history of GERD
21
Q
Effects of local anesthetics on the heart
A
Inhibition of voltage gated sodium channels
slowed cardiac conduction (increased PR interval, widened QRS), decreased rate of depolarization, reduction in cardiac-contractility, depressed spontaneous pacemaker activity in the sinus node
22
Q
Signs of LAST
A
Initial signs and symptoms include agitation, confusion, dizziness, drowsiness, dysphoria, auditory changes, tinnitus, perioral numbness, metallic taste, and dysarthria. Without adequate recognition and treatment, these signs as symptoms can progress to seizures, respiratory arrest, and/or coma as well as cardiac toxicity
23
Q
Intra-lipid dose for LAST
A
20% lipid emulsion
1.5 ml/kg initial bolus (repeat in 5 mins if no effect)
Followed by 0.25 ml/kg/min for 30-60 mins
24
Q
Dantrolene MOA and dose
A
binds to the ryanodine receptor, inhibiting calcium release from the sarcoplasmic reticulum (SR)
Loading dose 2.5 mg/kg, may repeat in 5-10 mins
(Limit 10 mg/kg)
maintain with 1 mg/kg q 4-6 hours at least for 24 hours after MH episode
25
ABG in malignant hyperthermia
ABG analysis will reveal a combined mixed resp and metabolic acidosis, along with associated hyperkalemia
26
Aortic stenosis categories by Valve area and gradient
Normal valve area 2.5-4.0
Mild valve area 1.5-2.0, valve gradient <25 mmHg
Moderate valve area 1.0-1.5, valve gradient 25-40 mm Hg
Severe valve area 0.7-1.0, valve gradient 40-50 mm Hg
Critical valve area <0.7, valve gradient > 50 mm Hg
27
6 indications for IE prophylaxis
1) Prior episode of IE
2) Cyanotic heart lesion unrepaired
3) Prosthetic cardiac valve or prosthetic material used for valve repair
4) Repaired congenital heart disease with residual defects at the site or adjacent to the site of a prosthetic patch or device
5) Cardiac transplant patients who develop cardiac valvulopathy
6) 6 month post-op period following repaired congenital heart defect using prosthetic material or device
28
SQH & Neuraxial
small dose for DVT prophylaxis - 4-6 hr delay before block placement or catheter removal if 5000U BID or TID, check platelets of > 4 days due to possibility of HIT, monitor aPTT
29
IV Heparin & Neuraxial
Delay 2-4 hrs after administration, do not give heparin until 1 hour after neuraxial
30
Complete heparinization (i.e. for cardiac surg) and neuraxial
Delay heparinization 60 mins following neuraxial
Removal delayed 2-4 hrs and until normal coags restored
Surgery delayed 12-24 hrs following traumatic needle placement
Monitor aPTT & ACT
31
LMWH & neuraxial
10-12 hrs after low dose and 24 hrs after high dose
Low dose is 30-40 U BID or Qday
High dose is 1 mg/kg BID or 1.5 mg/kg per day
Post-op:
For prophylaxis/low dose: catheter removed 10-12 hrs following last dose, subsequent dosing delayed 2 hrs after catheter removal
For therapeutic: lovenox delayed 24 hrs after surgery and catheter removed 2 hrs prior to administration
32
Warfarin & neuraxial
Delay neuraxial until INR normal, Coumadin should be d/cd 4-5 days and INR < 1.5
Monitor PT/INR
33
Clopidogrel & neuraxial
7 days
34
Ticlopidine & neuraxial
14 days
35
Prasugrel & neuraxial
7-10 days prior to placement, hold for 6 hrs after catheter removal or neuraxial instrumentation
36
Pradaxa (direct thrombin inhibitor) & neuraxial
5 days, contra-indicated with indwelling catheter
37
Fondaparinux & neuraxial
if 5-10 mg qday: delay 72 hrs
if < 2.5 mg qday: delay 48 hrs
Both contra-indicated with indwelling catheter
38
Apixaban/rivaroxaban & neuraxial
Delay 72 hrs, delay further dosing for 6 hrs following instrumentation or catheter removal
Direct factor Xa inhibitors
39
Cardioversion energy for afib
Monophasic: 200 J
Biphasic: 100-120 J
40
Addisonian crisis
Life threatening condition due to insufficient cortisol production
Fever, abdominal pain, dehydration, nausea/vomiting, hypoglycemia, acidosis, hyperkalemia, hyponatremia, AMS
41
Nitroglycerine vs. Nitroprusside vs. Nicardipine
Nitroglycerine: significant venodilation and some arterial vasodilation
Nicardipine: less venodilation, more likely to reduce afterload without affecting ventricular preload
Sodium Nitroprusside: direct acting vasodilator with more selectivity for veins than arteries but works on both (can cause cyanide toxicity)
42
Conditions not to give sux
```
MS
Paralysis
Burn victims
Bedbound
MH
MD
Stroke
GBS
```
43
Risks of perioperative hyperglycemia
Infection/Impaired immune response, impaired wound healing, dehydration, electrolyte disturbances
44
What FVC predicts post-operative ventilatory support?
< 30-35%
45
Extubation Criteria
all muscle relaxants fully reversed
vital capacity > 10-15 ml /kg
tidal volume > 5-6 ml/kg
SpO2 > 90%/PaO2 > 60 on 40-50% FiO2 with < 5 cm PEEP
Protecting airway/responsive to simple commands
Arterial pH > 7.3
Other possible criteria
RSI < 100
NIF > -20-30
46
Cobb angle re: pulmonary dysfunction
```
< 10 normal
surgery recommended if > 40-50
Often pulmonary dysfunction at > 60
> 70 pHTN w/ exercise
> 110 pHTN at rest
```
47
Muscular Dystrophy & anesthesia
Caused by recessive X linked mutation
Duchenne muscular dystrophy (DMD) - complete loss of dystrophin
Becker Muscular Dystrophy (BMD) - partially functional dystrophin protein
May have increased susceptibility to MH but in any case are at risk for an MH like syndrome & hyperkalemia with sux --> non triggering anesthetic
Delayed gastric emptying, diminished laryngeal reflexes, macroglossia
Cardiac issues --> MVP, pHTN
48
Common paraneoplastic syndromes
Humoral Hypercalcemia - tumor release of PTHrp
SIADH - hyponatremia, decreased serum osm, euvolemia
Cushing's syndrome - increased ACTH or CRH, hypokalemia, alkalosis, HTN, psychosis
Lambert Eaton Myasthenic Syndrome - most commonly associated w/ small cell
49
LEMS vs. MG
LEMS - antibodies to prejunctional voltage gated calcium channels, released ach release at the motor end plate, proximal weakness of the lower extremities, autonomic dysfunction, strength improves with repeated muscle activity
MG - antibodies to post-synaptic nicotinic acetylcholine receptors at the NMJ, strength improvs with rest, starts with bulbar involvement
50
Contra-indications to mediastinoscopy
1. STRONG contraindication = previous mediastinoscopy
Relative contraindications include: severe tracheal deviation, cerebrovascular disease, severe cervical spine disease with limited neck extension, previous chest radiotherapy, thoracic aortic aneurysm
51
Signs and symptoms of SVC Syndrome
headache, facial neck and upper limb edema, chest pain, dysphagia, lightheadedness, orthopnea, hoarseness, nasal stuffiness, nausea, pleural effusions, papilledema, visual disturbances, mental confusion, facial cyanosis, cough, JVD
52
Monitoring during mediastinoscopy
Mandatory to have some monitoring of the right radial/RUE - can be aline, pulse ox or continuous palpation
53
Alternative labor pain control to epidural
lamaze, NSAIDs, IV narcotics, TENS, regional blocks: paracervical for stage 1 and pudendal for stage 2
Paracervical: high risk of fetal bradycardia & decreased uteroplacental perfusion
54
Dermatomes for pain of different stages of labor
First Stage
Sympathetic nerve fibers (going through the inferior hypogastric plexus on the way to the sympathetic chain) that originate from the T10-L1 segments of the spinal cord (referred to the back as well as abdominal wall).
Second Stage
Pain for the second stage is transmitted via the pudendal nerve (S2-4)
For csection need to cover up to T4
55
Stages of Labor
Stage I: A) Latent phase
Variable duration
Starts at onset of labor
Complete when the rate of cervical dilation increases (~ 3 cm)
B) Active phase (contractions every 2-3 mins, last 1 min, up to 70 mm Hg)
Normal active labor should progress 1 cm/hr
Most common measure of uterine activity is the Montevideo unit (avg intensity frequency per 10 minutes)
Stage II: interval between maximal dilation and delivery (20-120 mins)
Stage III: placental delivery (5-20 mins)
56
What is DIC
Pathological activation of the coagulation cascade causing wide spread small clots in blood vessle,s consuming coagulation factors and platelets
Leads to thrombocytopenia, hemolytic anemia, diffuse bleeding, thromboembolic phenomena
57
Lab findings of DIC
```
Increased PT & PTT
Decreased fibrinogen < 100 mg/dL
Thrombocytopenia
Decreased AT3
Presence of fibrin degradation products and d-dimer
```
58
Treatment of DIC
Treat hypovolemia, low BP, hypoxemia and acidosis
Administer cryo (if fibrinogen < 50), FFP, platelets, PRBCs
59
Needle thoracostomy location vs. chest tube location
14g in the 2nd intercostal space mid clavicular line
CT: 4th or 5th intercostal space anterior to the mid axillary line
60
Accounting for difference between measured BP and circle of willis
subtract 0.77 mm Hg for every cm gradient
61
recommended CPP
at MAP 70-80
62
How to diagnose pheo
```
plasma free metanephrines
plasma catecholamines
plasma chromagranin A
total urinary catecholamines
urinary metanephrines
urinary VMA (vanillylmandelic acid)
Clonidine suppression test
MRI, CT or scintigraphy
```
63
alpha blockade for pheo
Should be initiated 10-14 days prior to surgery
phenoxybenzamine
some say to to d/c 24-48 hrs before surgery to reduce risk of hypotension
64
why alpha blockade before beta blockade for pheo
blockade of vasodilitory B2-receptors results in unopposed vasoconstriction, hypertensive crisis and CHF
65
drugs to avoid in pheo
succinylcholine (abdominal fasciculations), histamine releasing drugs (morphine, atracurium), increased sympathetic activity such as atropine, pancuronium ketamine, ephedrine, halothane, droperidol, reglan, ephedrine
66
Treatment of HTN during pheo
nicardipine
sodium nitroprusside
short acting agents such as phentolamine, esmolol, dilt, mag
67
Hunt & Hess classification
used to grade the severity of non-traumatic SAH
0 = unruptured aneurysm
1 = asymptomatic with minimal headache
2 = moderate to severe headache, cranial palsy or no neuro deficit
3 = drowsy, confused or mild focal deficit
4 = stupor, hemiparesis, vegetative disturbances
5 = deep coma, moribund, decerebrate posture
68
How to provide neuroprotection during neuro cases (like aneurysm clipping)
```
Thiopental, propofol, barbiturates
Higher MAP than normal
Minimize occlusion time of clip
Neuromonitoring (EEG & SSEP)
Brain relaxation (CSF drainage, mannitol, hypocapnia)
Mild hypothermia (32-34 degrees)
```
69
Hypothermia induced oxygen consumption reduction?
5-7% for every 1 degree C
70
Post-op complications from cerebral aneurysm
```
#1 = cerebral vasospasm
hematoma, seizure, increased ICP, pneumocephalus, metabolic derangements
```
71
Normal PaO2 formula for age
102-(age/3)
72
Acid/Base Compensations
Acute respiratory acidosis = Hco3 up by 1/10 mm Hg
Chronic resp acidosis = hco3 up to 4/10 mm Hg
Acute rep alkalosis = Hco3 down by 2/10 mm Hg
Chronic resp alkalosis = Hco3 down by 4/10 mm Hg
Acute metabolic acidosis = PaCo2 down by 1.2x the decrease in hco3
Acute metabolic alkalosis = Paco2 up by 0.7x the increase in hco3
73
Which side DLT and what is standard sizing
LEFT is easier to place due to early right RUL take off
35 and 37 L for women
39 and 41 L for men
standard
74
Risks of TURP
```
hypothermia
bladder perforation
hemorrhage
hemolysis
fluid overload
DIC
septicemia
hyponatremia
hyperglycinemia (glycine solutions)
hyperammonemia (glycine)
hyperglycemia (sorbitol)
```
75
AHA/ACC guidelines for recent MI
If BMS --> wait 1 month
If DES --> wait 12 months ideally, 180 days at minimum, absolutely do not proceed with d/cing antiplatelet agents before 3 months
Elective surgery as long as MI occurred more than 4-6 weeks ago and no further myocardium at risk
14 days after balloon angioplasty
76
Drugs to avoid in pseudocholinesterase deficiency
succinylcholine, and mivacurium, as well as ester local anesthetics, including cocaine and procaine
77
Dibucaine number
The amount pseudocholinesterase is inhibited by dibucaine
80% is normal
40-60% is heterozygous
20-40% is homozygous (1/2500-3000)
78
Causes of postop visual disturbances
Corneal abrasion
Acute glaucoma - severe and diffuse periorbital pain, dry pale eye, dilated pupil
Glycine toxicity - serum glycine > 17 mg/L, dilated/nonreactive pupils, normal IOP, fundus exam & eye movement
Cortical blindness - normal pupillary response
Hemorrhagic Retinopathy - vision spots/floaters, unilateral or bilateral, blurry vision, retinal edema
Retinal Ischemia - branch and central retinal artery occlusion, initially normal optic disc then becomes pale and edematous, painless
CRAO: cherry red macula, absent light reflex
Branch RAO: normal light reflex
Ischemic optic neuropathy - painless visual loss, absent light reflex, visual field deficits or complete vision loss
AION: optic disc edema and/or hemorrhage
PION: optic disc appears normal initially
79
How to perform awake fiberoptic intubation
Topicalized or nebulized 1-2% lidocaine (glossopharyngeal)
Superior Laryngeal nerve block: 2 ml of 2% lidocaine anterior to the cornu of the hyoid on each side
Transtracheal recurrent laryngeal nerve block
80
Airway Innervation
SENSORY:
-Maxillary branch of the trigeminal nerve --> supplies sensory innervations to the nasopharynx
-Glossopharyngeal nerve --> sensory of the posterior 1/3rd of the tongue, pharynx and areas above the epiglottis
Larynx from epiglottis to the cords --> Superior laryngeal nerve
Mucosa below the cords --> Recurrent Laryngeal Nerve
MOTOR
- The recurrent laryngeal nerves supply all of the intrinsic muscles of the larynx except for the cricothyroid muscle
- Cricothyroid muscle is innervated by the external branch of the superior laryngeal nerve.
81
Myasthenia Gravis
Autoimmune disorder, antibodies to the postsynaptic nicotinic acetylcholine receptor
With repeated stimulation, muscles fatigue
Associated with thymus hyperplasia, thymomas, other autoimmune disorders
Effectively fewer receptors, so resistant to sux, sensitive to nondepolarizers
82
Predictors of post-op ventilation in myasthenia gravis
1) Disease Duration > 6 years
2) Daily pyridostigmine dose > 750 mg
3) Concurrent respiratory disease such as COPD
4) Vital capacity < 40 mL/kg
83
Lambert-eaton syndrome
Autoantibodies to pre-synaptic calcium channels that prevents acetylcholine release
Strength improves with repeated stimulation
Usually proximal limb weakness
Sensitive to both depolarizing & nondepolarizing muscle relaxants
Often seen as a paraneoplastic syndrome
84
Cholinergic symptoms
DUMBBELLS
| diarrhea, urination, miosis, bronchorrhea, bronchospasms, emesis, lacrimation, laxation, sweating
85
Cor pulmonale EKG signs
Right atrial hypertrophy: peaked P waves in II, III and avF
| RVH: right axis deviation, partial or complete RBBB
86
Types of crisis in SCD Patient
```
Vaso-occlusive
Aplastic
Splenic sequestration
Hemolytic
Acute chest
```
87
Pre op hemoglobin goal for SCD patient
> 10, especially if hemodynamically unstable in any way
| Prefer HbAA at least 50%
88
Contributing factors to myocardial ischemia
Inadequate oxygen supply to meet metabolic demands
```
Causes of decreased supply:
tachycardia
anemia
hypoxia
decreased coronary perfusion pressure (hypotension, vasospasm, coronary obstruction, severe AS, severe AR, elevated LVEDP)
```
```
Causes of increased demand:
tachycardia
increased wall tension
contractility
increased afterload (systemic hypertension)
```
89
Coronary perfusion pressure
Aortic diastolic pressure minus left ventricular end diastolic pressure
CPP = AoDBP-LVEDP
90
ACC/AHA BB Recommendations (2014)
Beta blockers should be continued in patients undergoing non-cardiac surgery who have been on the drugs chronically.
It may be reasonable to begin perioperative beta blockers for patients with intermediate or high risk myocardial ischemia, or for patients with three or more Revised Cardiac Risk Index risk factors such as heart failure, coronary artery disease, renal insufficiency, diabetes mellitus, or even cerebrovascular accident.
Initiation of therapy should be long enough in advance to assess the safety and tolerability of any beta blocker before surgery - at least one day but preferably 2-7 days
Do not initiate beta blocker on the day of surgery (class 3, harm)
91
Revised Cardiac Risk Index
1) Elevated-risk surgery - Intraperitoneal; intrathoracic; suprainguinal vascular
2) History of ischemic heart disease
3) History of congestive heart failure
4) History of cerebrovascular disease - prior TIA or stroke
5) Pre-operative treatment with insulin
6) Pre-operative creatinine >2 mg/dL / 176.8 µmol/L
Risk of major cardiac event* per score:
0 - 3.9% (2.8-5.4%)
1 - 6.0% (4.9-7.4%)
2 - 10.1% (8.1-12.6%)
≥3 - 15% (11.1-20.0%)
*Defined as death, myocardial infarction, or cardiac arrest at 30 days after noncardiac surgery (from Duceppe 2017).
92
Jet ventilation initial pressures for peds vs. adults
5-10 psi for kids
| 15-20 psi for adults
93
Jet ventilation complications
Not recommended for: decreased chest wall compliance 2/2 obesity, restrictive lung disease, gastric distention etc OR reduced exhalation (COPD, laryngospasm, glottic lesions, etc)
1) misalignment of the gas jet causing poor ventilation and gastric distention
2) transmission of blood, smoke, debris into the distal airways
3) excessive vocal cord vibration
4) barotrauma - pneumomediastrinum, subQ emphysema, pneumothorax
94
Steps for airway fire
1) Alert the OR
2) disconnect airway from oxygen supply/circuit
3) remove the ETT
4) Flood airway with saline
5) Once fire over ventilate with 100% O2
6) Perform DL/rigid bronch to asses for airway edema and remove debris
7) Re-intubate and delay extubation for 24 hrs
8) consider chest Xray, steroids, pulm consult, monitor closely
95
Toxic dose of lidocaine
With epi 7mg/kg
Without epi 5 mg/kg
Liposuction 55 mg/kg (w/ normal hepatic function and no inhibition of P-450)
96
Liposuction complications
Related to obesity but also, perioperative fluid overload, pulmonary edema, LAST, systemic epinephrine uptake, cardiac arrythmias, pulmonary embolism
97
Toxic doses of bupivacaine
2.5 mg/kg without epi
| 3 mg/kg with epi
98
Toxic dose of ropi
3 mg/kg
99
How to perform celiac plexus block
Patient in the supine position, place two needles about 5-7 lateral to the midline at the L1 level, advance needles under fluoroscopy until they are just anterior to L1 and after aspiration and confirming not intra-vascular inject local anesthetic for test block, if pain resolves then inject either alcohol or phenol
100
Complications of celiac plexus block
Most common: orthostatic hypotension
Most serious: paralysis due to spinal or epidural damage or damage to the artery of adamkiewicz
Others: diarrhea, RP hemorrhage, sexual dysfunction, pneumothorax, damage to the kidneys or pancreas
101
CRPS types
Type 1: RSD - minor injuries, burns, crush, surgery, etc
| Type 2: Causalgia - known nerve injury
102
CRPS Diagnostic Crtieria
Budapest criteria
Must report at least one symptom in all four of the following categories:
1) sensory – reports of hyperaesthesia and/or allodynia
2) vasomotor – reports of temperature asymmetry and/or skin colour changes and/or skin colour asymmetry
3) sudomotor/oedema – reports of oedema and/or sweating changes and/or sweating asymmetry
4) motor/trophic – reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin).
Must display at least one sign at time of evaluation in two or more of the following categories:
1) sensory – evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or temperature sensation and/or deep somatic pressure and/or joint movement)
2) vasomotor – evidence of temperature asymmetry (> 1 °C) and/or skin colour changes and/or asymmetry
3) sudomotor/oedema – evidence of oedema and/or sweating changes and/or sweating asymmetry
4) motor/trophic – evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
There is no other diagnosis that better explains the signs and symptoms.
103
Acute epiglottitis
Most common age 2-7
Caused by HiB most frequently
Sudden onset
Fever, drooling, stridor, respiratory distress
Inspiratory stridor indicating supraglottic obstruction
Thumbprint sign on xray
104
Signs of acromegaly
```
Skeletal and soft tissue overgrowth
Large mandible, tongue, soft palate, epoglottis
HTN
Accelerated atherosclerosis
Cardiomyopathy
OSA, arthritis, insulin resistance
Glottic stenosis
RLN Palsy
```
105
Terbutaline
beta agonist
relaxes uterus and airways (can be used for asthma and premature labor)
can cause pulmonary edema
106
Locations and their local anesthetic systemic absoprtion
IV > tracheal > intercostal > caudal > paracervical > epidural > brachial plexus > sciatic/femoral > subQ
In time i can please everyone but sister sally
107
Factors that affect local anesthetic uptake
Location
Lipid solubility --> Higher lipid solubility decreases rate of systemic absorption
Protein binding --> higher protein binding decreases rate of systemic absorption
Use of Epi --> decreases systemic absorption
108
Congenital heart defects associated with cyanosis
Anything that causes right to left shunt
```
1 - Truncus arteriosis
2 - Transposition of the great vessels
3 - Tricuspid atreisa
4 - Tetrology of Fallot
5 - TAPVR
```
109
What is tetrology of fallot
Most common cyanotic congenital heart legion
4 defects
1) VSD
2) RVOT Obstruction
3) Overriding aorta
4) Right ventricular hypertrophy
110
Causes of tet spells
Crying, feeding, defecating, tachycardia, hypovolemia, increased myocardial contractility
sudden increase in PVR
dynamic outflow obstruction of the RV
decrease in SVR
111
Autonomic hyperreflexia
Intra-op HTN & bradycardia with painful stimulus below the level of the lesion, at risk with injuries T7 and above
Because of sympathetically mediate vasoconstriction below the lesion causing reflex vasodilation above the lesion
Above lesion: nasal stuffiness, headache, visual changes, dysrhythmias, nausea, confusion and difficulty breathing
112
Pre renal vs. renal lab differences
FeNA:
Pre-renal - 1% or less
Renal - > 2%
BUN:Cr
> 20 - prerenal
< 10-15 - renal
Urine osmolarity (mOsm/L)
> 500 in prerenal
< 400 in renal
Urine Na
< 20 mEq/L in prerenal
> 40 mEq/L in renal
113
Drugs for treatment of thyrotoxicosis
Methimazole - decrease thyroid hormone synthesis
PTU - decrease thyroid hormone synthesis
Iopanoic acid - reduce T3
Potassium iodide - blocks Thyroid hormone synthesis via Wolff-Chaikoff effect
Glucocorticoids - block peripheral conversion of T4 to T3
114
How to assess bilateral RLN injury
Have patient say "EE" they will be aphonic
115
Stridor after thyroidectomy?
Laryngeal nerve injury, laryngospasm, bronchospasm, tracheomalacia, hematoma formation, inadequate muscle relaxant reversal, residual anesthetic, hypocalcemia (though usually takes 24 hrs to develop after inadvertent Parathyroid removal)
116
Signs of functional carcinoid tumor
Flushing, diarrhea, bronchospasm, dramatic swings in BP, increased HR or palpitations, heart murmurs (tricuspid or pulmonary lesions), right heart failure
117
How to diagnose carcinoid tumor
urinary 5-HIAA
| serum chromogranin A
118
Metabolic disturbance caused by octreotide
glucose intolerance
119
pheos rule of 10
10% bilateral
10% malignant
10% familial
10% extra-adrenal
120
What is presentation of CDH & what is CDH?
neonate with scaphoid abdomen, absent breath sounds on the left, respiratory distress
herniation of abd contents into the left thoracic cavity, results in impaired maturation of lung tissue - decreased # of alveoli, decreased surfactant, abnormal pulmonary vasculature, pHTN
121
Normal A-a gradient
young adult non-smoker < 10 mm Hg
in CDH patients > 500 predicts non-survival, < 400 predicts survival
122
Initial treatment of CDH neonate
```
Medically stabilize
Avoid PPV
Establish IV access
Supplemental O2
Intubate (awake or RSI)
Orogastric or NG tube
Avoid high airway pressures > 30 cm H20 (increased risk of PTX on contralateral side)
Muscle relaxant to reduce oxygen consumption
Order ABG, CXR, echo
```
123
Sux for peds
IM: 3-5 mg/kg
IV: 1-2 mg/kg
124
Atropine for peds
IM: .02 mg/kg
IV: .01-.02 mg/kg
125
Epi for kids
1 mcg/kg for hypotension/bradycardia
| 10 mcg/kg for arrest
126
Pedi fluid bolus
10-20 ml/kg
127
CDH Mechanical ventilation
Permissive hypercapnia (45-55 mmHg)
Pressures < 30 cm H20
High frequency oscillatory ventilation (HFOV)
Rapid respiratory rate of 60-120 breaths/min
128
Pulmonary vasodilators for neonates
PGE1 - can cause systemic hypotension, will also maintain the PDA (reduce RV afterload, however does increase shunt)
NO - specific pulmonary vasodilator, inactivated by exposure to Hgb so doesn't affect SVR
Milrinone - may be good in case of RV failure
129
Contraindications to Pedi ECMO
```
Gestation < 34 weeks
Weight < 2000g
Significant IVH (must be anticoagulated on ECMO)
Congenital heart disease
> 1 week aggressive respiratory therapy
```
130
Placing an umbilical vein line
STERILEY drape and prep
Caudal traction on the umbilical stump (cephalad traction will facilitate umbilical artery catheterization)
Insert soft catheter filled with heparinized solution to the right atrium
131
Complications of umbilical vein catheterization
```
Infection/sepsis
Thrombosis of portal or mesenteric vein
Portal cirrhosis
Endocarditis
Cardiac tamponade
Liver abscess
Hemorrhage
Subcapsular hematoma
```
132
Retinopathy of prematurity
vasoproliferative retinopathy, infants less than 44 weeks postconceptual age
1) Exposure to high O2 leads to vasoconstriction & obliteration of the retinal vessels resulting in insufficient vascularization of the retina
2) Leads to abnormal neovascularization and fibrous tissue/scar formation w/ possible hemorrhage
133
Normal difference between pre-ductal and post-ductal SpO2
5-10%, higher indicates significant right to left shunt through PDA or coarctation of the aorta
(in this case increase SVR & decrease PVR to correct)
134
EKG in pregnancy
Normal to have left axis deviation, sometimes ST segment depression
135
Leads II, III, aVF
Inferior (RCA, LCx)
136
Leads I, aVL, V5 & V6
Lateral (LCx or diag)
137
V2-V4
Anterior (LAD)
138
V1, V2
Septal (LAD)
139
ACC/AHA guidelines for LV assessment
Indicated for:
- Dyspnea of unknown origin
- Current or prior HF with worsening dyspnea or other change in clinical status
- Reassessment of patients with LV dysfunction with no recent evaluation in past 12 months
140
Contraindications to magnesium therapy for pre-eclamptic
- Cardiac dysfunction (can cause hypotension, bradycardia, cardiac arrest, CHB)
- Myasthenia gravis
- Impaired renal function
- Concomitant calcium channel blocker therapy
141
Magnesium Toxicity Levels in mEq/L
1.5-2.5: normal
4.0-7.0: therapeutic
7.0-10.0: Loss of patellar reflexes, hypotension, CNS depression
13-15: respiratory paralysis
16-25: EKG changes prolonged PR, widened QRS, prolonged QT
20-25: Cardiac arrest
142
What increases risk of hypermagnesemia?
Hypocalcemia
Hyperkalemia
Renal insufficiency
Digitalis Therapy
143
Hs & Ts
```
Hypovolemia
Hypoxia
Hydrogen Ion Excess (Acidosis)
Hyper/Hypokalemia
Hypothermia
```
Toxins (drugs)
Tamponade
Tension Ptx
Thrombosis (coronary/MI or PE)
144
Maternal ACLS when to deliver baby?
Within 5 mins if mom not recovering, improves outcomes for mom and baby to have emergent C-section
145
Estimated blood volume (EBV)
EBV = weight in kg x average blood volume
```
Premature neonates = 90-100 ml/Kg
Pregnant female = 90 ml/kg
Full term neonate = 80-90 ml/kg
Child 3-12 months of age = 70-80 ml/kg
Child > 1 yr = 70-75 ml/kg
Obese child = 60-65 ml/kg
Adult men = 75 ml/kg
Adult women = 65 ml/kg
```
146
Estimated allowable blood loss
= [EBV x (Hi-Hf)] / Hi
147
Aortic stenosis grading by valve area and mean transvalvular gradient
```
Valve area:
normal 2.5-4 cm2
mild 1.5-2
moderate 1.0-1.5
severe 0.7-1.0
critical < 0.7
```
```
Mean transvalvular gradient
normal: none
mild < 25
moderate 25-40
severe 40-50
critical > 50
```
Hyperdynamic nature of pregnancy makes the gradient overestimate the severity, better to use valve area in pregnant patients
148
Indications for bacterial endocarditis prophylactis
1) Patients with prosthetic cardiac valves
2) Patients with previous infective endocarditis
3) Cardiac transplant recipients with valve regurgitation due to a structurally abnormal valve
4) Patients with congenital heart disease with:
- Unrepaired cyanotic congenital heart disease, including palliative shunts and conduits,
- Totally repaired congenital heart defect repaired with prosthetic material or device that has been placed by surgery or catheter intervention, during the first 6 months after the procedure
- Repaired congenital heart disease with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device
Patients with these high-risk conditions should receive antibiotics for the following procedures:
1) Dental procedures that involve manipulation of gingival tissue, manipulation of the periapical region of teeth, or perforation of the oral mucosa. This does not include routine anesthetic injections through noninfected tissue, dental radiographs, placement or adjustment of orthodontic devices or trauma to the lips and teeth.
2) The 2007 AHA guidelines also recommended prophylaxis for invasive respiratory tract procedures that involve incision or biopsy of the respiratory mucosa (e.g., tonsillectomy, adenoidectomy). Antibiotic prophylaxis has not been recommended for bronchoscopy unless the procedure involves incision of the respiratory tract mucosa.
3) Procedures of infected skin, skin structures, or musculoskeletal tissue.
Prophylaxis against IE is not recommended in patients who are at risk of IE for other nondental procedures, for example, TEE, esophagogastroduodenoscopy, colonoscopy, or cystoscopy, in the absence of active infection.
149
When to give exogenous steroids?
If patient is on at least 5 mg pred per day for more than 7 days
100 mg hydrocort pre op followed by 100q8 then taper
(if minor surgery can just give 25 mg)
To prevent Addisonian crisis: fever, abd pain, dehydration, nausea/vomiting, hypoglycemia, acidosis, hyperkalemia, hyponatremia, AMS, circulatory collapse
150
Esmolol
short acting BB that is B1 selective so safe for asthmatics
151
Positioning concerns for prone cases
Spinal cord injury (esp if pre existing injury or neck surgery)
Pressure induced injury to the eyes, ears, nose, breasts, genitals, knees, toes
Position related obstruction of venous drainage leading to elevated ICP or IOP
Brachial plexus injury if abduction by more than 90 degrees
152
Elective surgery after cardiac event/stents
14 days after balloon angioplasty
30 days following BMS
6 months following DES (may be considered after 3 mo with newest stents if risk of surgery delay is greater than risk of stent thrombosis)
153
Anesthesia risks specific to spinal cord injury patients
1) Autonomic hyperreflexia
2) Pulmonary dysfunction (impaired diaphragm function, chronic pulmonary infections due to impaired cough)
3) Renal dysfunction (recurrent stones, chronic UTIs)
4) Altered thermoregulation (absence of cutaneous vasoconstriction)
5) Anemia
6) Cardiac conduction abnormalities
7) Decreased neck ROM
8) Bone fractures due to osteoporosis
9) Ulcers & DVTs
154
Risk of sux induced hyperkalemia highest how long following injury?
24 hrs - 1 year (but really highest at 5 months)
155
Pressure difference between main pipeline O2 and cylinder O2
main pipeline: 50 psig
backup o2 cylinder: 45 psig
(disconnect from main pipeline if there is a problem with the o2 supply there otherwise main pipeline will preferentially be used)
156
Approximate time remaining in Oxygen E-cylinder in hours
Time in hours = oxygen cylinder pressure (psig)/[200 x oxygen flow rate in L/min)
157
Treatment of autonomic hyperreflexia
1) Stop stimulus
2) Deepen anesthetic
3) Direct acting vasodilator such as sodium nitroprusside
4) Ensure bladder is emptying
5) Place aline, intubate if needed, etc.
158
Normal closure of the ductus arteriosis
Functionally closed within 2-4 days of birth
Permanent closure with fibrosis takes several weeks
With first breath the PVR decreases and SVR increases
Arterial O2 increases with ventilation
Leads to a reversal of flow through the ductus, exposing it to systemic blood with high O2
Rapid decrease in circulating prostaglandins from placenta (mostly E2)
Combination of the above closes the duct
Prostaglandin inhibitors such as ibuprofen/indomethacin can speed closure
159
Risk factors for PDA
1) prematurity
2) respiratory distress syndrome (RDS)
3) Hypoxia
4) Acidosis
5) Excessive fluid therapy
160
Complications of PDA ligation surgery
1) Recurrent laryngeal nerve injury
2) left phrenic nerve injury
3) Thoracic duct injury (chylothorax)
4) Massive blood loss
5) Hypertension
6) Re-opening of the duct
161
Risks specific to newborns (esp low birth weight and premature infants)
```
Hypothermia
Retinopathy of prematurity
Intraventricular hemorrhage
Postoperative apnea
Hypoglycemia
Poor temperature regulation/management
```
162
Post operative apnea in infants
Admit (24 hr observation) all infants younger than 60 weeks PCA is most conservative management
Risk of apnea is related to both gestational age and actual age
Anemia is a risk factor
Apnea at home is a risk factor
SGA (small for gestational age) is protective
High dose caffeine (10 mg/kg) and theophylline (because neonates metabolize the drug to caffeine) have been used as respiratory stimulants to prevent and/or treat postoperative apneic episodes.
Blood transfusion in anemic infants is not clearly beneficial in preventing post-operative apnea
163
Glucosuria in infants
Normal before 34 weeks gestation due to reduced renal tubular reabsorption of glucose
Abnormal > 34 weeks
164
Optimal FiO2 and PaO2 to reduce risk of ROP in infant?
FiO2 87-94%
| PaO2 50-80 mm Hg
165
When to administer blood products to infants
Normal healthy full term infant: not until hematocrit at 20-25%
For sick premature neonate might consider above 40%
166
Neutral temperature
Temperature at which oxygen consumption is minimized
Adults: 28 C
Term neonate: 32 C
Preterm neonate: 34 C
167
Anesthesia concerns in SVC Syndrome
Difficult airway due to airway edema and mass compression
Massive hemorrhage
Upper extremity IVs non functional
Compromised cerebral perfusion
Increased risk of respiratory complications
Avoid coughing and bucking
168
Complications of medastinoscopy
```
Tracheal compression or laceration
Cerebrovascular events
RUE Ischemia
Compression of the aorta leading to reflex bradycardia
Pneumothorax
RLN Injury or phrenic nerve injury
Venous air embolism
Mediastinal hemorrhage
Esophageal tear
```
169
What does pituitary do?
```
Anterior: makes stores and secretes
ACTH
LH
FSH
TSH
GH
Prolactin
```
Posterior: stores and secretes
oxytocin
ADH
170
Bromocriptine
Synthetic dopamine-2 receptor agonist, inhibits secretion of GH and prolactin, can cause gastroparesis
171
Octreotide
somatostatin analogue, inhibits release of GH, can shrink pituitary tumors
172
Debakey classifications of aortic aneurysms
Type I - originate in the ascending aorta and extend distally to the descending aorta
Type II - originate in the ascending aorta and do not extend beyond the innominate artery
Type III - originate beyond the left subclavian and extend distally to the diaphragm (A) or the aorto-iliac bifurcation (B)
173
Stanford Classification of aortic aneurysms
Type A - involve the ascending aorta (with or without the arch and descending)
Type B - The ascending aorta is not involved
174
Crawford classification system
For classifying thoracoabdominal aortic aneurysms
| Types 1-4
175
How to evaluate pulmonary function in pre-op
History: Frequency of pulmonary infections, severity and frequency of exacerbations, exercise tolerance, number and course of hospitalizations, efficacy of treatments
Physical exam: cough, sputum, lung sounds, clubbing, cyanosis
Studies: CXR and if poor functional status or something on the CXR then order ABG, PFTs, ECG
176
Reason for lumbar drain
Clamp increased CSF pressure (hyperemia above clamp -> increased ICP -> redistribution of CSF into intrathecal space -> increase in CSF pressure by 10-15 mmHg)
Cord perfusion pressure = mean distal aortic pressure - CSF pressure
177
Contraindications to ANH
1) anemia - initial crit < 33 or hgb < 11
2) Impaired renal function - may be unable to excrete the volume load
3) Aortic stenosis or other conditions that would make an increase in cardiac output undesirable
4) Significant pulmonary disease that may impair oxygen delivery to the tissues
5) pre-existing coagulopathy
178
Monitors for thoracic aneurysm case
```
5 lead ekg
upper and lower extremity alines
central line
PAC
T/c TEE
Core & peripheral temp monitors
SSEPs & MEPs
Foley Catheter
```
179
PAC Signs of myocardial ischemia
Prominent A waves - atrium contracing into a stiff left ventricle
Prominent V waves - mitral regurgitation
Increased PAOP and PAdP - increased LVEDP
180
Important considerations of anesthetic for open thoracic aneurysm repair
```
TIVA for neuromonitoring
Maintain HR 60-80
Keep cardiac index 2-2.5 L/minute/m2
Stable anesthetic for neuromonitoring
SBP 105-115
MAP ~100 above cross clamp and > 50 distal to cross clamp
Hypothermia while clamped (30-34 C)
Target ICP 8-10 mmHg
```
181
Spinal cord blood supply
Anterior - motor, one anterior spinal artery (from the basilar and vertebral arteries ) supplies anterior 2/3rds of the cord, also from radicular arteries form the aorta including artery of adamkiewicz which is variable but most often at T9-T12
Posterior - sensory, two posterior spinal arteries that supply the posterior 1/3rd of the cord
182
What is TEG?
Measures viscoelastic properties of blood during clot formation to evaluate clot formation kinetics and growth as well as the strength and stability of the formed clot
183
TEG Parameters and what they mean
R - the time to initial clot formation, intrinsic pathway factor function, problem with coagulation factors, treat with FFP
K & alpha angle - speed of clot formation, representing thrombin & fibrin formation, problem with fibrinogen, treat with cryo
MA - strength of the clot, reflection of platelet number and function, treat with platelets
LY30 - lysis at 30 mins, problem with excess fibrinolysis, treat with amicar or TXA
184
What potentiates lithium toxicity?
Thiazide diuretics
Salt restriction/low sodium
NSAIDs
Ace inhibitors
185
Lithium affects on anesthetic
Decreases MAC
Potentiates NMB (both depolarizing and nondepolarizing)
Can cause AV heart block, arrhythmia, AMS, widening QRS, hypotension or seizures
186
Optimizing thyroid status
Consult endocrine
PTU - inhibits organification of iodine, synthesis of TH and peripheral conversion
B-Blocker - propranolol
Glucocorticoid - reduce thyroid hormone secretion and peripheral conversion
Iodide - reduce release of T4 & T3
Hydration
187
Signs of end organ dysfunction from HTN
- LVH
- Angina
- MI
- CHF
- CAD
- Stroke
- TIA
- CKD
- Retinopathy
- Peripheral arterial disease
188
Causes of HTN
- CKD
- Renovascular disease
- Steroid therapy
- Sleep apnea
- Drugs
- Alcohol
- Obesity/metabolic syndrome
- Thyroid or parathyroid disease
- Pheo
- Coarctation of the aorta
189
What potassium level to delay elective surgery
> 5.5
190
Drugs given during kidney transplant
Heparin prior to clamping of iliac vessels
CCB or papaverine into arterial graft to prevent vasospasm
Mannitol and/or lasix prior to revascularization of graft
191
How to treat uremic thrombocytopathia?
HD! Quickest and most effective. If that doesn't work, platelet transfusion. Also can consider DDAVP to increase release of vWF.
192
Systemic manifestations of RA
Joint involvement of the cervical spine, TMJ or cricoarytenoid joints can predispose to difficult intubation
ALSO:
Pericardial thickening, pericarditis, pericardial effusion
Myocarditis, aortitis, cardiac valve fibrosis
MI, diastolic dysfunction
pHTN
rheumatoid nodules in cardiac conduction system
Pleural effusions, pulmonary fibrosis
ILD
Peripheral neuropathy, carpal tunnel
Liver or kidney dysfunction
Anemia of chronic disease
193
If you have to give uncrossed blood what are you giving
Type O negative PRBCs
Can switch to type specific blood ASAP
194
Esophagectomy considerations
Pt at high risk for aspiration and pneumonitis/pulmonary fibrosis
Check for other liver or kidney dysfunction as patients often abuse other drugs or alcohol
Thoracic epidural is standard of care
Nutritional status important
periop afib is common
Chemotherapy toxicity assess preop
Postop pulmonary complications common - ARDS
dumping syndrome can result
can have phrenic, vagal or laryngeal nerve injury
can get anastomotic leak, stricture or stenosis
195
Contraindications to cell saver
- Pre existing hemoglobinopathy
- Contamination with drugs like betadine, chlorhexidine, topical abx, methyl methacrylate
- Contamination with urine
- Contamination with amniotic fluid
- Contamination with bowel contents
- Pheo
- Malignancy (relative contraindication if washed, leukoreduced, filtered)
196
Complications of cell saver
- Hemolysis
- Systemic contamination
- Nephrotoxicity due to high free hemoglobin
- Coagulopathy
- Pulmonary injury 2/2 leukocyte activation
- Gas embolism
- Fever
197
At what Po2 does HbS start sickling
PO2 of about 50 mm Hg, but it is time dependent, o even though vein are about 40 mm Hg only 5% sickle on the way to the lungs
198
What is aplastic crisis and why is it so dangerous for patients with SCD?
Temporary shut down in RBC production by the bone marrow, this is caused by virus or infection (esp parvovirus) or folate deficiency. With SCD, RBC lifespan is greatly shortened (usually 10-20 days), and a very rapid drop in Hb occurs.
199
Avoiding sickle cell complications during anesthesia:
minimize exposure to hypoxemia, hypercapnia, acidosis, hypothermia, and hypovolemia during surgery. Transfuse PRBCs as necessary. Adquate oxygenation and ventilation
200
Two phases of amniotic fluid embolism
1. pHTN/pulm vasospasm, hypotension 2/2 right HF, hypoxia (VQ mismatch), seizure, cardiac arrest
2. LV failure, pulmonary edema, coagulopathy/DIC
201
Nitrous oxide and retinal srugery
Discontinue NO 15 minutes prior to intravitreous bubble
Air - avoid NO 5 days
Sulfure Hexafluoride - Avoid NO 10 days
Perfluoropropane - Avoid NO 30 days
Can cause expansion of intravitreous bubble, lead to increased IOP leading to retinal and/or optic nerve ischemia, CRAO... also rapid reabsorption of it can cause repeat retinal detachment
202
Treatment of acute chest
1) Chest PT, bronchodilators, supplemental O2, incentive spirometry
2) Abx for atypical and encapsulated organisms
3) Adequate pain control
4) Correct anemia
5) Consider exchange transfusion and intubation if severe
203
What is acute porphyria?
results when one of the enzymes in heme biosynthetic pathway is deficient resulting in overproduction of porphyrins
In patients with porphyria, increase in heme requirements such as anemia or cytochrome-P450 metabolism can trigger an attack by reducing feedback inhibition on ALA synthetase
204
Factors that cause porphyria attacks
Fasting, dehydration, stress, infection
Thiopental, thiamylal, methohexital, etomidate, ketorolac, phenacetin, nifedipine
205
Characteristics of AIP attack
abd pain, nausea, vomiting, psychiatric disturbance, autonomic nervous system instability, electrolyte disturbances, hypovolemia, seizures, skeletal muscle weakness, quadriparesis, respiratory failure & bulbar paralysis
206
Moderate Sedation "Conscious sedation"
Drug induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions required to maintain a patent airway and spontaneous ventilation is adequate
207
Trauama resuscitation steps
Initial rapid assessment: stable, unstable, dying, dead
Primary Survey: Airway, breathing, circulation, disability, exposure (ABCDE)
Secondary Survey: Systematic evaluation of the patient from head to toe for additional injuries, radiographs, diagnostic procedures and lab tests ordered
Tertiary survey: within first 24 hrs to identify anything else missing, pre existing comorbidities and medical record etc
208
Normal mixed venous oxygen tension (PvO2)
35-45 mm HG
209
Normal mixed venous O2 saturation
65-75%
210
Base Excess normal vs abnormal
< -2 = metabolic acidosis
-2 to +2 = normal
> 2 = alkalosis
211
Parkland formula
Fluid replacement with LR at a rate of 4 ml/kg per % burned BSA in first 24 hrs, half of that in first 8 hours, other half over the next 16 hours
212
Rule of 9s
```
Each of these is 9% of total BSA:
Head and neck
Each upper extremity
Chest
Upper Back
Abdomen
Lower Back
Anterior aspect of each lower extremity
Posterior aspect of each lower extremity
```
213
Burn depth classification
First Degree: Limited to epidermis
Second Degree: Injury involving the epidermis and dermis
Third Degree: Complete destruction of the epidermis and dermal layers
Fourth Degree: Involvement of the muscle, fascia, and/or bone
214
Burn depth classification
First Degree: Limited to epidermis
Second Degree: Injury involving the epidermis and dermis
Third Degree: Complete destruction of the epidermis and dermal layers
Fourth Degree: Involvement of the muscle, fascia, and/or bone
215
Burns - when to intubate?
> 10% TBSA full thickness burns or
> 25% TBSA partial thickness burns
Because of risk of progressive airway edema and copious secretions leading to respiratory distress or airway obstruction
216
Signs of inhalational injury
```
Burn within a closed space (building)
Soot stained sputum
Singed facial hair
Burned mucosa
Cough
Stridor
Hoarseness
Difficulty swallowing
Pharyngeal edema
```
217
Problems with sodium bicarb administration
1) Generation of additional Co2 which worsens intracellular acidosis
2) Left shifting of oxyhemoglobin curve
3) Hyperosmolar state secondary to sodium load
4) Hypokalemia (movement of K+ from extracellular to intracellular compartment)
Only give if pH below 7.1
218
Normal pulse ox wavelengths
960 nm and 660 nm
219
CO poisoning pathology
CO has a 200-250 fold greater affinity for hemoglobin so it takes up binding sites but also, results in left shift of the oxyhemoglobin dissociation curve
220
Treatment of CO poisoning
100% O2
Observe blood for cherry red color (Means CO-Hb > 40%)
Order CO-Hg level
221
What level of CO-Hg needs hyperbaric oxygen therapy?
> 25-30%
222
Conditions where SpO2 does not approximate SaO2
methemoglobinemia
carboxyhemoglobinemia
severe anemia
certain dyes, nail polishes, poor perfusion
223
How to assess oxygenation status in carbon monoxide poisoning?
co-oximetry
224
Signs of compartment syndrome
Pallor
Paresthesias
Paresis (late finding)
Pulselessness
225
When is immediate surgery required in compartment syndrome?
Pressure of 30-40 mm Hg or < 30 mm Hg difference between the intra-compartmental pressure and the diastolic BP
226
CV changes after a burn injury
Immediate (first 24-48 hrs) - high SVR and low CO due to circulating myocardial depressant factors
Afterwards there is a hyperdynamic increased cardiac output state (2x) normal and SVR is reduced
227
Larson's maneuver
Jaw thrust and apply firm pressure at the ascending ramus of the mandible, to relieve laryngospasm
228
Steps if you think patient has laryngospasm
1) Call for help and difficult airway cart
2) Eliminate foreign material or secretions from oropharynx
3) Provide jaw thrust and pressure at ascending mandible
4) Gentle PPV using 100% oxygen
5) Deepen anesthetic, IV lidocaine
6) 30 degree reverse T to relieve tissue obstruction
7) Consider sux .5 mg/kg to relieve laryngospasm
8) if intubation unsuccessful place LMA
229
When to avoid sux after burn?
From 24 hrs to 1-2 years following burn injury
230
Bone cement implantation syndrome
Hypotension, hypoxia, dysrythmias, pHTN, decreased CO and even cardiac arrest associated with bone cement
1) Hardening of the cement results in high intra-medullary pressures and embolization of bone marrow debris
2) Circulating methl methacrylate monomer may lead to reduced SVR
3) Release of cytokines
231
Complications of jet ventilation
pneumothorax, pneumomediastinum, pneumoperitoneum, pneumopericardium, subcutaneous emphysema, inadequate gas exchange, gastric distention, regurgitation, gastric rupture
232
Who should not get jet ventilation?
Patients with decreased chest wall compliance (obesity)
Patients with upper airway obstruction i.e. glottic lesion (inhibits exhalations)
Advanced COPD due to need for prolonged expiratory phase & risk of bullae rupture
233
Hypothalamus induced increase in core temperature associated with major burn injury
1-2 degrees C
Hypermetabolic response to thermal injury
Also have increased glycogenolysis, gluconeogesis, severe fat and protein wastin, increased oxygen demand
234
How to treat rhabdo?
Alkalinization of the urine - controversial
235
How to differentiate hemoglobinuria from myoglobinuria 2/2 skeletal muscle destruction?
Serum is pink stained in hemoglobinuria, normal in myoglobinuria
236
Abdominal compartment syndrome
Results when trauma, fluid resuscitation and/or sohck results in massive edema of intra-abdominal organs
Causes cardiac pulmonary renal GI hepatic and CNS dysfunction
Measure intravesical pressure with a foley catheter (if > 20-25 mmHg this is abdominal HTN)
237
Pacemaker Coding
First position = chamber paced
Second position = Chamber sensed
Third = Response to sensing (O - none, T - triggered, I - inhibited, D - dual)
Fourth = Rate modulation (O - none, R - rate modulation)
Fifth = Multisite pacing (0 - none, A - atrium, V - ventricle, D - dual)
238
Defibrillator Coding
First - shock chambers
Second - Antitachycardia pacing chambers
Third - tachycardia detection (E = electrogram, H = hemodynamic)
Fourth - Antibradycardia pacing chambers
239
Questions to ask when patient has a pacemaker or AICD
1) Indication?
2) Model & type?
3) Pacemaker dependent?
4) Programmed pacing mode?
5) Number, types and age of leads?
6) Behavior when exposed to a magnet?
7) Battery status?
8) Underlying rhythm and rate?
9) Any alerts?
240
How to decide where to put current return pad for EMI (bovie pad)?
As far from the site of the IPG as possible and as close t the site of surgery as possible, ensure that the path is 6 inches at least away from the CIED
241
Ok to use sux in globe injury?
Yes, only transient increase in IOP for 1-4 minutes, very minor compared to coughing or bucking. Can pretreat with nondepolarizer to prevent fasciculations
242
Defibrillation energy
Biphasic: 120-200 J
AED: 150-200 J
Monophasic: 360 J
243
Ways to prevent airway fire during laser surgery?
1) laser safe ETT, rubber ETT or ETT wrapped in reflective foil
2) Saline filled ETT cuff
3) Limit duration and intensity of laser
4) Keeping O2 concentration below 30%
5) Consider apneic anesthetic technique or jet ventilator
244
APGAR Scores
Appearance - cyanotic 0, acrocyanotic 1, pink 2
Pulse - absent 0, below 100 1, above 100 2
Grimace - floppy 0, minimal response to stimulation 1, normal response to stimulation 2
Activity (muscle tone) - absent 0, flexed arms and legs 1, normal 2
Respirations - absent 0, slow/irregular 1, strong cry/normal 2
245
Roller pumps for CBP
Roller pump: forward flow is produced by partial compression of tubing by roller heads, not sensitive to preload or afterload, can deliver pulsatile flow, reliably produces flow
Disadvantages:
Increased damage to RBCs, potential delivery of air, risk of over-pressurization leading to tubing separation or rupture, risk of preload occlusion leading to negative pressure induced cavitation and causing development of microscopic bubbles
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Centrifugal pump for CBP
Rotational force responsible for forward flow, less damaging to RBCs, sensitive to changes in preload and afterload, will cease function if air is entrained
Disadvantages:
Incapable of delivering pulsatile flow, only able to partially compensate for decreases in forward flow resulting from increases in distal pressure
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Which type of pH management during CBP in adults and peds?
Adults: alpha stat (don't add back Co2)
Peds: pH stat (add back CO2)
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pH stat vs. alpha stat management
Alpha stat - does not add back Co2 to correct to pH 7.4 and PCO2 of 40
pH stat - does add back Co2 to correct ph. used in peds. causes cerebral vasodilation and increase in cerebral blood flow.
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PCWP tracing: c wave
elevation of the mitral valve during early ventricular systole
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PCWP tracing: v wave
venous return against a closed mitral valve
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PCWP tracing: x descent
downward displacement of the atrium during ventricular contraction, atrial relaxation
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PCWP tracing: y descent
decline in atrial pressure as the mitral valve opens during diastole
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PCWP tracing: a wave
atrial contraction
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PCWP with mitral regurgitation?
tall V wave, abolished x descent, rapid y descent
255
What to do with intraop afib
Rate control B blocker, CCB, digoxin if stable
| if unstable amiodarone or DC cardioversion
256
What to do if there are low venous reservoir volumes on CBP?
Reduce pump flows and add fluid to the blood volume
| Look for potential causes of decreased venous return such as elevation of the heart or problems with the venous cannula
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Why valsalva when preparing to come off CBP?
1) Recruit alveoli
2) De-air the heart - PPV causes increased blood flow through pulmonary vasculature, displacing air into the left heart where it can be removed with a vent
258
Increasing PA pressures with decreasing systemic pressures is indicative of what?
Left heart failure
259
How to position IABP
Tip at the junction of the aortic arch and descending aorta
| Synchronize to cardiac cycle using the arterial pressure wave form or EKG QRS
260
Aline following CBP?
Radial may be 30 mm Hg lower than central aortic pressures 2/2 peripheral vasodilation with rewarming, resolves in 45 mins
261
Signs of cardiac tamponade?
JVD, muffled heart sounds, hypotension (Becks triad), dyspnea, tachycardia, orthopnea, pulsus paradoxus, narrow pulse pressure
262
What is pulsus paradoxus?
Exaggerated decrease in BP with inspiration (> 10 mmHg systolic)
Due to increased venous return during inspiration, filled RV, bulges into LV causing decreased filling, reduces stroke volume & systolic pressure
263
Pyloric stenosis
Nonbilious projectile vomiting, small abdominal mass below the right costal margin (olive), metabolic derangements from vomiting include hypokalemic, hypochloremic, hyponatremic metabolic alkalosis. Compensatory respiratory acidosis.
This is a medical emergency not surgical, do not proceed with case until patient has been medically optimized
Typical give normal saline to replace sodium and chloride and supplement with potassium as needed, avoid LR since the lactate is converted to bicarb worsening the alkalosis
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How to assess a baby's volume status?
- Fonantelles
- BP & HR
- Skin turgor, mucous membranes
- volume and frequency of vomiting
- Urine output/number of wet diapers
- Diarrhea present?
- Any change in weight
- Mental status
- CBC, electrolytes, ABG, urine studies with BUN
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What is osteogenesis imperfecta?
```
Connective tissue disorder, abnormal synthesis of Type I collagen, affects bones, ligaments, dentition and sclera
Diagnosis often from multiple fractures in various stages of healing
-Blue sclera
-Fractures from minimal trauma
-Kyphoscoliosis
-Bowing of femur or tibia
-Hearing loss 2/2 otosclerosis
-Coagulopathy (platelet dysfunction)
-Hyperthyroidism
-Cardiovascular problems - PDA, septal defects, mitral & aortic regurg, aortic dilation, aortic dissection
-Craniocervical instability - AA or AO
-Quadriparesis
-Megalocephaly
-Short neck/stature
-Macroglossia
```
266
How does dehydration result in contraction alkalosis?
Kidneys have to reabsorb sodium which brings bicarb with it and excretes hydrogen
267
Advantages of a circle system over a mapleson?
1) More effective preservation of heat & humidity
2) Reduced waste of expensive anesthetic gasses
3) Reduced operating room pollution
4) Reduced dead space
268
Contraindications to esophageal stethescope?
```
Esophageal varices
Esophageal strictures
Tracheostomy creation (surgeon may mistake stethoscope for ETT and open the esophagus by accident)
```
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Next step if you intubate pedi patient and then can't ventilate?
1) Turn to 100% oxygen & Hand ventilate
2) Check circuit for kink, obstruction
3) Check ETT for patency, suction ETT
4) Verify proper ETT placement by auscultation and/or fiberoptic
Consider bronchospasm as #1 on differential if the above are all normal
5) Look for any signs of aspiration such as gastric material in the oropharynx and suction if so
6) Apply positive pressure
7) Deepen anesthetic
8) Administer B2 agonist and possibly small dose of Epi
270
Treatment for post extubation croup in peds?
```
Dexamethasone
Humidified inspired gasses
Nebulized racemic epi
Light sedation if needed
Ensure adequate hydration
Consider reintubation with ETT 1/2 to 1 size smaller
```
271
Risk factors for post-intubation croup in peds?
```
Oversized ETT
Repeated attempts at intubation
Intraoperative changes in patient position
Surgery duration > 1 hour
Traumatic intubation
Patient between 1-4 years old
Coughing on ETT
Volume overload
Head and neck surgery
Co-existing URI
Previous history of croup
```
272
Considerations in patients with OI for anesthesia
1) Difficult airway: neck instability, macroglossia
2) Don't use BP cuff b/c of risk of long bone fracture use aline instead
3) Thrombocytopathias common, check coags and clinical signs of bleeding
4) Can have hyperthermia during anesthesia thatis NOT MH
5) Don't use sux due to fasciculation induced fractures
6) Don't use IO lines
7) Don't use direct nerve stimulation during blocks because of risk of fractures
8) Avoid cricoid due to risk of fracture
273
Classifications of sleep apnea by AHI
severe: > 30 events/hr
moderate: 16-30
mild: 5-15
274
Definition of OSA
Complete cessation of airflow for more than 10 seconds occurring 5x or more per hour despite continued respiratory effort against a closed glottis and associated with a > 4% decrease in SpO2
275
Definition of OSH (obstructive sleep hypopnea syndrome)
Milder form of OSA
Sleep study demonstrates 50% reduction in airflow for more than 10 seconds, 15 or more x per hour, associated with > 4% decrease in SpO2
276
What is obesity-hypoventilation syndrome (OHS)
Develops secondary to obesity or long term consequences of OSA
Constellation of obesity, daytime arterial hypercapnia (PaCO2 > 45), nocturnal hypoxia, polycythemia in the absence of known pulmonary disease
277
What is Pickwickian syndrome
Severe form of OHS, chronic hypoventilation leads to pHTN and RV failure
278
Anesthetic considerations for a patient with OSA
1) Presense of coexisting disease such as HTN, CAD, arrythmias, pHTN, RV failure
2) Regional preferable
3) Airway management might be difficult (difficult mask and intubation)
4) Extreme sensitivity to CNS depressants
5) Extubation should be fully awake, upright, fully reversed, etc
6) Multimodal analgesia and minimize narcotics and benzos
7) Appropriate discharge criteria/monitoring
8) Increased platelet aggregability - more susceptible to thromboci and embolic events such as cardiac events & CVA
9) Polycythemia - same as above
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Airway exam in short/memorize this for airway exam
History and review of prior medical records including past intubations if available, Mallampati score, nasopharyngeal characteristics, neck circumference, tonsil size, tongue size, mouth opening, thyromental distance, cervical range of motion, any abnormalities of the airway
280
Nitrous oxide effect on PVR
Increases it
281
Flammable airway gasses
O2 and nitrous oxide
| Helium is inert
282
Dosing of common anesthetic drugs based on IBW or TBW?
```
Propofol: induction IBW, maintenance TBW
Midazolam: loading TBW maintenance TBW
sux: TBW for both
vec/roc: IBW for both
atra/cis: TBW for both
fent/sufent: TBW loading then IBW for maint
remi: IBW for both
```
283
Amio dosing for an arrythmia such as afib
Bolus 150 mg over 10 mins then 1 mg/min for 6 hours then 0.5 mg/min for another 18 hrs (max dose 2.2 g/24 hrs)
284
Most likely causes of afib?
can be idiopathic
most likely related to cardiac disease such as valvular disease, LVH, CAD, HTN, cardiomyopathy, sick sinus syndrome, pericarditis
non-cardiac conditions include: hyperthyroidism, PE, alcohol, caffeine
285
How does dilt work for afib?
Used to control the heart rate by decreasing the rate of SA node and slowing conduction through AV node, has negative inotropic effects so should be used with caution if patient has HF
286
Anesthetic considerations for patients with TR
Avoid decreased preload or increase RV afterload
Avoid hypoxia, hypercarbia, nitrous oxide, hypovolemia, decreased SVR, excessive airway pressures
287
What is R on T phenomenon?
Superimposition of an ectopic beat on the T wave of a preceding beat, ventricular extrasystole caused by a ventricular depolarization superimposing on the previous beat's repolarization
Shock delivered during the vulnerable period of ventricular repolarization (near the end of the T wave) when it is more likely to facilitate vfib
288
Most sensitive and specific sign of cardiac tamponade?
Diastolic collapse of the right atrium, RV or LV on TEE
289
"Safe Discharge" Criteria
1) Stable vital signs
2) controlled n/v
3) Absence of unexpected bleeding
4) Adequate pain control with oral analgesics
5) Ability to walk without dizziness
6) Provision of discharge instructions and prescriptions
7) Responsible escort
290
What to do for PONV
1) Check blood glucose and ensure stable vital signs, oxygenation, pain control, fluids
2) Give zofran
3) Give alternate class of medication such as droperidol or promethazine
291
Risk factors for PONV
Patient factors: female, nonsmoker, prior motion sickness or PONV, anxiety
Anesthetic factors: Volatile, nitrous, neostigmine, intraop or postop opioids
Surgery factors: Laparoscopy or laparotomy, ENT, strabismus, breast, neurosurgery, plastic surgery
292
How to treat status asthmathicus?
1) Supplemental O2 to keep sat > 90%
2) B2 agonists, corticosteroids, aminophylline, empirical broad spectrum abx
3) Order PFTs and ABGs to monitor treatment
4) Consider iV Mag sulfate
5) Consider mechanical ventilation
293
What mode of ventilation for status asthmaticus?
Pressure control with a prolonged expiratory time: decelerating flow pattern will more efficiently overcome high resistance of asthmatic airways, minimize peak pressures, improve distribution of ventilation
Avoid auto-PEEP breath stacking
294
History and physical for signs of CHF or ischemia?
angina, orthopnea, dyspnea on exertion, exercise tolerance
| Peripheral edema, pulmonary rales/edema, S3 gallop, murmurs
295
MVP auscultation?
Systolic ejection click
296
Anesthetic goals for patients with MR
Decrease afterload
Maintain preload
Keep HR in the high normal range (80-100)
Avoid increases in PVR
297
Anesthetic goals for patient with MR due to MVP
```
Avoid sympathetic activation
Maintain SVR
Maintain preload
Avoid increased contractility
Avoid tachycardia
```
