Differential Diagnoses Flashcards
Hypoxia
A). Low inspired O2 concentration
B). Hypoventilation
-apnea
- obstruction
- trauma
- mechanical causes (disconnection)
C). Shunt - V/Q mismatch
- atelectasis
- mucous plugs
- pneumo-/hemo-/chylothorax
- pleural effusion
- endobronchial intubation/ OLV
- pulmonary edema
- pneumonia/pneumonitis
- aspiration
- bronchospasm
- pulmonary embolism
- inhibition of hypoxic pulmonary vasoconstriction (HPV)
- decreased MvO2
- intracardiac shunt
- pulmonary artery-venous fistula
- during one long ventilation
D). Increased diffusion barrier
- pulmonary edema
- pneumonia
- fibrosis
E). Baseline conditionHypercarbia
A). Increased production
- MH (malignant hyperthermia)
- Serotonergic Syndrome
-shivering
-seizure
-Thyroid storm
-sepsis
-fever
-excessive carbohydrate intake
-Reperfusion Syndrome
-bicarbonate administration
-release of tourniquet or aortic crossclamp
B) Decreased Elimination
1). Hypoventilation:
-iatrogenic; drug induced (sedatives, NMB); high spinal; phrenic nerve palsy; vent settings; OLV; retractors; permissive hypercapnia)
- patient: central, COPD, CHF, pneumothorax, increased intra-abdominal pressure; airway/ETT obstruction; pulmonary edema
2). Rebreathing
- incompetent inspiratory/expiratory check valve
-exhausted soda lime
3). Inadequate flow with Mapleson system
4). Increased dead space ventilation:
- pulmonary edema
- COPD
- Endobronchial ETT
C). CO2 use
- Laparoscopy
- pH stat with CPBDifference between Malignant Hyperthermia vs. Neuroleptic Malignant Syndrome vs. Thyroid Storm
All have hypercarbia, hyperthermia, and tachycardia, however…
- MH has respiratory acidosis and/or lactic acidosis, hyperkalemia, elevated CK, and rigidity typically NOT associated with Thyroid Storm. Tx with Dantrolene
- Thyroid Storm is associated with HYPOkalemia and usually presents postoperatively
- Neuroleptic Malignant Syndrome (NMS) mental status changes occur over 1-3 days and is associated with dopamine blocking agents (e.g. Haloperidol, olanzapine, metoclopramide, droperidol, etc.). Tx with Dantrolene, bromocriptine, amantadine.
Differential diagnoses for wheezing
Lower airway vs. Upper airway
Lower airway:
- kinked tube
- mucous plug
- herniated cuff
- foreign body
- endobronchial intubation
- pneumothorax
- bronchospasm
- pulmonary embolism
- cardiogenic
- anaphylaxis
- aspiration
- Carcinoid
- Baseline condition
Upper airway:
- laryngeal edema
- laryngospasm
- laryngomalacia
- foreign body
- vocal cord paralysis
- infection
- tumor
- polyps
- baseline condition
Differential diagnoses for Hypotension
Hypoxia Hypercarbia (very late) Dysrhythmia - bradycardia - tachycardia - non sinus rhythm - asystole - Pacemaker failure
Decreased afterload
- vasodilation
- hypovolemic shock
- septic shock
- anaphylactic shock
- neurogenic shock (high spinal or cord injury)
Decreased preload
- all types of shock noted above
- aortic crossclamp or unclamping
- pneumothorax
- embolism (pulmonary, air, fat, amniotic fluid)
- IVC occlusion
- tamponade (high airway pressures)
Impaired myocardial function:
- ischemia
- acidosis
- hypocalcemia
- cardiomyopathy
- electrolyte disorder ( hypocalcemia)
- valvular disease
- congenital heart disease
- vegetation or myxoma
Carcinoid crisis Addisonian crisis Drug effect Erroneous value Baseline condition
Addisonian Crisis vs Carcinoid Crisis
Addisonian crisis:
- hyperthermia
- tachypnea
- tachycardia
- hypotension
Carcinoid Syndrome
- skin flushing
- diarrhea
- tachycardia
- shortness of breath
- diarrhea
Hypertension
A). Artifact - small cuff -lowered a-line transducer B). Patient -light anesthesia -pain -withdrawal -rebound hyperalgesia -Pheochromocytoma (epi, norepi) -Hyperthyroidism (Thyroid storm) -Autonomic hyperreflexia (stimulation below level of spine injury) -Neuroleptic Malignant Syndrome (NMS) -Serotonergic Syndrome -HTN -increased ICP -Renal artery stenosis -elevated aldosterone -pre-eclampsia/ eclampsia -drugs (cocaine, ephedra, PCP, etc) C). Iatrogenic -light anesthesia -drugs -aortic cross clamp -Malignant Hyperthermia -ECT/ seizure -overload (?) -hyperalgesia (?)
Hypotension
A). Artifact -large cuff -elevated a-line transducer B) Preload -NPO -diuretic -bowel prep -dialysis -nausea/vomiting/diarrhea -bleeding -regional anesthesia (sympathectomy) -spinal shock -release of aortic cross clamp -CPB (initiation) -pneumothorax -dynamic hyperinflation -intrauterine pregnancy -laparoscopy -abdominal compartment syndrome -PE/VAE -cardiac tamponade -diastolic dysfunction C). Heart -dysrhythmia (Brady/tachy) -PPM failure -neohepatic D). Contractility -+/- drug -hypoxia/hypercarbia -CAD -cardiomyopathy (restrictive/obstructive) -LVF/RVF -HYPOcalcemia, HYPERmagnesemia, acidosis -post-CPB -IABP/VAD malfunction -Adrenal insufficiency (Addison's disease) E). SVR -sepsis -anaphylaxis - +/- drugs -vasoplegia: CPB, anaphylactic, proteins, ACEIs, cytokine release, Pheo resection -initiation of CPB -anemia -brain death -spinal shock F). PVR -baseline -protamine -hypoxia/hypercarbia -acidosis -PE/VAE/FE
Tachycardia
A). Artifact
-count T wave
B). Patient
-hypercarbia/hypoxia
-reflex with hypotension/hypovolemia
-withdrawal
-light anesthesia
-pain
-hyperalgesia
-Pheochromocytoma
-Hyperthyroidism
-Autonomic hyperreflexia
-NMS and Sertonergic Syndrome
-drugs
-anemia
C). Iatrogenic
-aortic cross clamp
-MH
-seizure/ ECTBradycardia
A) Patient
-hypoxia/hypotension
-ischemia
-elevated ICP
-vagal (valsalva, uterine inversion)
-carotid sinus manipulation
-spinal shock
-autonomic hyperreflexia (reflex response)
-HTN (reflex response)
-electrolytes (hyperkalemia, hypocalcemia)
-PPM failure
-dysrhythmia (heart block)
-congenital cardiomyopathies
-infectious (Lyme diphtheria, typhoid)
-endocrine (hypothyroidism)
-autoimmune (SLE)
-Athlete
-fetal
B). Iatrogenic
-drugs (digoxin, neostigmine, beta blockers, CCBs, opioids, phenylephrine, clonidine, amiodarone, organophosphates, inhaled anesthetics-halothane)
-high spinal
-Bezold-Jarisch Reflex (decreased RA volume leads to decreased HR)
-oculocardiac reflex
-severe hypothermia
-Hering-Breuer reflex (pulmonary stretch receptors)
-VAE (initially tachycardia)
-Fetal Combined Spinal-epidural reflex (sudden release of maternal pain and reduction in circulating catecholamines leads to unopposed uterine constriction causing fetal distress briefly
Postpartum Bleeding
- Uterine atony (most common cause)
- retained placenta
- uterine inversion
- ## genital trauma
Antepartum Bleeding
- placenta previa
- abruptio placenta
- uterine rupture
Physiological changes in pregnancy
1) . Airway:
- engorged and increased friability of nano/oropharyngeal mucosa
2) . Respiratory:
- increased minute ventilation
- decreased FRC
- tidal volume increases (due to diaphragmatic excursion)
- ABG shows slightly decreased PaCO2 (32 mmHg) with compensatory decrease in HCO3 (22 mmHg) = pH 7.44
- rightward shift of Ox-Hgb dissociation curve (P50 = 30)
3) . Cardiac
- LVH (seen by 12 wks gestation)
- Grade I or II early or mid-systolic murmur (likely TR)
- increased CO
- increased HR
- increased SV (stroke volume)
- slight decrease in BP
- aortocaval compression
4) Hematologic
- increased blood volume yet decreased Hct (55% increased plasma volume and 30% increase in RBC volume)
- Increased Factors 1, 7, 8, 9, 10, and 12 inducing hypercoaguable state; Factors 11, 13, and Antithrombin 3 decreased.
- decreased plasma proteins (25% decreased plasma cholinesterase
5) . GI
- upward displacement of stomach
- decreased LES
- increased pH of gastric fluids
6) . Renal
- RBF increases; GFR increases
7) . Endocrine
- increased sensitivity to insulin (predisposes to DM) glucose tolerance impaired
- increased thyroid size due to follicular hyperplasia and vascularity
8) . Neuromuscular
- decreased MAC
- distention of vertebral plexus reduces epidural and intrathecal spaces
Low airway pressure
1) . ETT –>patient
- extubation
- de-/under inflated cuff
- ruptured cuff
- Tracheobronchial disruption
- Bronchopleural fistula
- OG tube in trachea
2) . Machine —> ETT
- low tidal volumes
- circuit leak
- machine leak/malfunction
High Airway Pressure
NOT Pulmonary Embolism (PE)
- pulmonary edema
- pneumonia
- pneumothorax/hemothorax/chylothorax
- bronchospasm
- obstruction: secretions, blood, foreign body, laryngospasm, kink or clog in ETT, hematoma
- atalectasis
- mainstem/OLV
Oliguria
A). Post-Renal
- foley kinked
- clot
B). Pre-Renal (FeNa <1)
- low CO/BP
- Hypovolemia
- Aortic cross clamp
- Nonpulsatile
C). Renal
- ischemia
- vasospasm
- nephrotoxins
- emboli
- cytokines
- reperfusion injury
Jaundice
A). Prehepatic
- Hemolysis: acute hemolytic transfusion reaction or delayed
- Hematoma reabsorption
- increased unconjugated = indirect bilirubin
B). Post-hepatic
- cholestatic: stones, inflammation, stenosis
- pancreatitis
- increased conjugated = direct bilirubin
C). Hepatic -hepatocellular disease
- chronic disease/ infectious (e.g. viral hepatitis)
- ischemic
- Drug-induced (acetaminophen, alpha methyldopa, isoniazid, sulfonamides, chloramphenicol, halothane)
- Gilbert’s disease: most common cause of idiopathic hyperbilirubinemia (unconjugated = indirect bilirubin) - Crigler-Najjar syndrome: rare form of severe unconjugated hyperbilirubinemia due to decreased or absent glucoronyl transferase; could lead to early death
- Dubin Johnson syndrome: decreases transport of organic ions from hepatocytes to the biliary system, producing a conjugated hyperbilirubinemia
- Fatty liver of pregnancy
- TPN
- Reperfusion injury
- Intrahepatic cholestasis
Delayed arousal
- Patient sensitivity to drugs
- hypoxia/hypercarbia/hypotension
- ischemia
- cerebral edema
- drugs: opioids, benzodiazepines, NMR, propofol, inhaled anesthetics
- CVA: intracranial hemorrhage, subarachnoid hemorrhage, venous sinus thrombosis
Things to do to decrease elevated ICP
1) . drain CSF
2) . hyperventilate (?)
3) . hypertonic saline > mannitol ; lassie
4) . elevate head of bed
5) . avoid hypoxia
6) . hypothermia (?)
Post-op stridor
1) . inadequate reversal of muscle relaxants
2) . hematoma
3) . bilateral RLN injury
4) . laryngospasm (secondary to hypocalcemia can be seen >24 hrs post-op)
5) . airway edema
6) . laryngomalacia
7) . residual anesthetic
Ruling out cervical spine injury
1) . Normal level of alertness with
2) . absence of focal neurological deficits
3) . absence of tenderness at posterior midline
4) . No evidence of intoxication
5) . Absence of clinically apparent distraction/injury
CT scan
MRI of cervical spine helps rule out injury
However, SCIWORA (spinal cord injury without radiography abnormality mostly affecting children) may still exist.
Systemic changes in SLE
1) . Airway/Respiratory
- pulmonary HTN (can stretch RLN)
- pneumonitis
- fibrosis
- pulmonary embolism
- vocal cord edema/nodules
2) . Cardiac
- pericarditis/myocarditis
- tamponade
- MR/AR
3) Neuro
- psych
4) . Hematologic
- antiphospholipid antibody (hypercoaguable state)
- anemia (Coomb’s positive)
5) . Joint/skin
- rash
- arthritis
- myositis
- oral ulcers
- osteopenia
Cardiac physiology of Aortic cross clamping (afterolad, preload, contractility, perfusion below AoX)
1) . Afterload: increases leading to HTN
2) . Preload:
- may INCREASE during SUPRAceliac AoX from redistribution from collapse of splanchnic vasculature
- may DECREASE during INFRAceliac AoX from redistribution of blood to dilated splanchnic vasculature
3) . Myocardial contractility
- may INCREASE (along with an increase in CO) as a result of the increase in after load and preload
- may DECREASE (along with a decrease in CO) as in the case of the myocardium with poor function, causing LV ischemia and failure
4) . Perfusion below the AoX depends on perfusion pressure, NOT preload or CO, raising concerns about excess SNP and suggesting a role for shunting
Physiology of releasing AoX
Hypotension due to pooling of blood in distal tissues; ischemia-mediated vasodilation; and release of accumulated vasoactive mediators and myocardial depressant factors
Differential diagnoses for prolonged QT syndrome
- aortic stenosis
- HOCM
- WPW
- myocarditis
- cardiomyopathy
- myxoma
- Brady/tachy
- congenital heart disease
a. Romano-Ward (autosomal dominant)
b. Jervell,Lange-Neilsen (autosomal recessive; assoc. deafness) - CAD
- seizures
- hyperventilation
- hypoglycemia
- Drugs:
Define Systemic Inflammatory Response Syndrome (SIRS)
a life threatening dysfunction caused by a dysregulatory response to infection
What is severe sepsis
Circulatory and celllular/metabolic abnormalities that are enough to substantially increase mortality with
- persistent hypotension requiring vasopressor support to maintain a MAP >/= 65
- serum lactate > 18 mg/dL despite high volume resuscitation
Possible complications from TURP syndrome
- Hyponatremia (mental status changes at 120 mEq/L; ST elevations at 115 mEq/L; LOC and seizure
- Pulmonary edema
- CV instability (HTN, Hypotension, Vfib)
- Glycine toxicity (post-op blindness)
- Perforation
a. exztraperitoneal (periumbilical/suprapubic/inguinal fullness)
b. intraperitoneal (N/V, pale, diaphoresis, hypotension, referred shoulder pain) - Obdurator Nerve stimulation
- Hypothermia
- Bleeding (fibrinolysis from urokinase)
- Bacteremia, sepsis (6-7%)
Drugs that may trigger methemoglobinemia
1) . local anesthetics
- Prilocaine (i.e. EMLA)
- Benzocaine (i.e. cetacaine)
2) . metoclopramide
3) . NTG
4) . SNP
5) . Phenytoin
6) . Sulfonamide
Treatment for methemoglobinemia
1) . Methylene blue (does NOT work in patient’s with G6PD deficiency –>worsens
- 2 mg/kg/5 mins
2) . Ascorbic acid
3) Exchange transfusion ?
4) . Hyperbaric Oxygen
Capacity vs. Competence
Capacity is your assessement of one’s ability to have sufficient understanding and comprehension
Competence is a LEGAL term assessing a patient’s ability to consent to specific treatment being offered
Distinguish SIADH from CSWS
Both are associated with HYPOnatremia and a urine osmolality > serum osmolality, however,
- CSWS is associated with HYPOvolemia and SIADH is not.
- SIADH has a correction of the low serum uric acid and fractional excretion of uric acid with water restriction
- SIADH has a greater ADH level
Treatment of CSWS vs. SIADH
CSWS treatment consists of:
- fluid and Na+ replacement
- possible use of fludrocortisone to promote tubular Na+ reabsorption
SIADH treatment consists of:
- Fluid restriction
- furosemide
- democlocycline, which inhibits ADH effect on renal tubules by inducing a nephrogenic DI (given if fluid restriction fails)
What is a Cobb angle and how is it relevant?
Cobb angle is the angle formed by the 2 perpendicular lines drawn from the lines of the 2 most maximally tilted vertebrae.
- > 10 degrees is abnormal
- respiratory impairment is rare < 60
What is the Hunt and Hess Classification system?
A clinical classification used in assessing intracranial aneurysms:
0: enraptured
I: ruptured with minimal headache
II: moderate-severe HA; no other deficit
III: drowsy/confused or mild focal deficit
IV: stupor, significant hemiparesis, early decerebrate posturing, vegetative disturbances
V: deep coma, decerebrate rigidity, moribund
Anesthetic management during an intracranial aneurysm clipping
1) . If clipping at the base of the aneurysm
- HYPOtension should be induced prior to clipping
2) . If a temporary clip is being placed on a feeding vessel first to minimize edema downstream,
- then induce HYPERtension
- Have Nicardipine ready
- Be ready for massive blood transfusion
When is vasospasm most likely to occur in regards to an intracranial aneurysm repair?
Post-op day 3-14
Expected FEV1 and FEV1/FVC ratio in COPD
decreased FEV1 and FEV1/FVC ratio
PFTs in restrictive Lund disease vs. obstructive
Restrictive
- decreased volumes and capacities
- normal flow rates
- normal FEV1/FVC ratio
Qualities of a difficult intubation on physical exam
Mouth -long incisors -overriding incisor -interincisor distance -short uvula -oral aperture Jaw -prognath jaw -short submandibular space -noncompliant submandibular space Neck -short neck length -large neck circumference -decreased ROM
Causes for difficult ventilation (MOANS)
- Mask difficult (beard, blood)
- Obesity (BMI >30) / obstruction
- Age >55
- No teeth (edentulous)
- Stiff lungs/ chest wall
- etc.: tonsils, polyps, trauma
What blocks are required for an Awake FOB?
1) . Oropharynx = Trigeminal nerve (V)
2) . Posterior Hypopharynx = Glossopharyngeal (IX)
3) . Vagus(X) = SLN & RLN
What is Cytokine Release Syndrome?
occurs with administration of antithromboglobulin (ATG) used as an immunosuppressant in renal transplants
-a cause of hypotension
Diseases associated with Malignant Hyperthermia
1) Central Core Disease (#1) - infancy hypotonia; linked to chromosome 19q13
2) . King-Denborough syndrome (short stature, mental retardation, prox. weakness, cryptorchidism, webbed neck, low set ears, and scoliosis)
3) . Myotonia congenital
4) . Schwartz-Jampel syndromes (dwarfism, craniofacial, and skeletal abnormalities, stiffness, blepharophimosis)
5) . Osteogenesis imperfecta
How does the pediatric airway differ from that of an adult?
1) . The head and tongue are larger
2) . the nasal passage is smaller
3) . the larynx is more cephalic, more anterior airway
4) . cricoid cartilage is the narrowest part of the airway
5) . epiglottis is long and stiff
6) . deciduous teeth may be loose
7) . airways are smaller
8) . the upper airway muscle are more sensitive to anesthetics
Why is the neonate more sensitive to anesthesia?
- less protein binding
- increased permeability of the BBB
- decreased drug elimination
- increased sensitivity to drugs
Fire Triad
1) . Oxidizer (oxygen, nitrous oxide)
2) . Ignition (laser, heated probe, FOB, electrocautery, defibrillator pads)
3) . Fuel (ETT, nasal cannula, surgical catheter, sponge, drape, EtOH, ether, acetone, hair dressing, endoscope, etc)
Reasons an epidural test dose can fail?
1) . patient is on a beta blocker
2) . elderly do not readily generate tachycardia
3) . patient could have a contraction
Goal CPP in patients with suspected increased ICP
Normal CPP = 50
Goal CPP = 60-70
Do not go above 70
Things to do to decrease ICP
1) . drain CSF
2) . hyperventilate (?)
3) . Hypertonic Saline > Mannitol; Lasix
4) . Elevate HOB
5) . Avoid hypoxia
6) . Hypothermia (?), STP (methohexital)
7) . Avoid hyperglycemia
Post-dialysis Disequilibrium Syndrome
slight cerebral edema causing delirium post-dialysis
Drugs to avoid giving in Breastfeeding mothers
1) . Hydromorphone (11 x more potent than Morphine)
2) . Codeine
3) . Gabapentin (neonatal sedation at large doses)
What are some physiologic complications of liver cirrhosis
A). Respiratory -decreased FRC (from ascites) -increased AV shunts (hepatopulmonary syndromes) -pleural effusions -inhibition of HPV from vasodilating substances (i.e. ferritin, vasoactive intestinal peptide, glucagon) -hypoxemia B). Cardiovascular -systemic AV shunts -HYPERdynamic state - increased CO from low SVR state and low viscosity; high output CHF may occur; mixed venous O2 may be high (as seen in sepsis) C). GI -portal HTN -ascites -GI bleeding (esophageal varies) -Hemorrhoids -Aspiration risk D). Hematologic -thrombocytopenia, neutropenia from splenic sequestration -anemia -coagulopathy E). Renal -Na+ retention -Hepatorenal syndrome (pre-renal oliguria with Na retention, azotemia, and ascites) FENa+ < 1 -impaired free water clearance -decreased renal perfusion F). Neurologic -Encephalopathy G). Metabolic -HYPOnatremia (dilutional) -HYPOkalemia (due to diuretics or hyperaldosteronism) -HYPOalbuminemia -HYPOglycemia H). Spontaneous bacterial peritonitis
What is shunted in a TIPSS procedure?
Transjugular Intrahepatic Portosystemic Shunt (TIPSS)
Shunt from the portal vein to the hepatic vein, bypassing the liver.
What test can be done to diagnose Piriformis Syndrome?
A form of back pain that can be illicited by doing the FLAIR maneuver: Flexion, Adduction, Internal Rotation
Recommended elective surgery delay with cardiac stents (Angioplasty vs Bare Metal vs Drug Eluting)
Angioplasty only: 2-4 weeks
Bare Metal: 4-6 weeks
DES: 6 months to 1 yr
Recommended interrogation timeline check for PPM vs. AICD prior to surgery
PPM must be interrogated within past year
AICD must have been interrogated within the past 6 months
ECG changes seen with HYPOkalemia
- ST segment depression
- increased QT interval
- decreased P wave
- decreased T wave and increased U wave
ECG changes in HYPERkalemia
- peaked T waves
- decreased QT interval
- widened QRS complex
- decreased P wave and increased PR interval
Define negligence
deviation from standard of care
Define standard of care
what a reasonable and prudent doctor would do
What are the components of Liability
1) . Duty
2) . Breech of that duty
3) . Harm was done
4) . Causation
Angioedema
A C1-INH deficiency that leads to elevated protein C levels, which lead to bradykinin release —> edematous airway, GI, and subcutaneous tissues
Factors that make a patient an elevated risk for a Major Adverse Cardiac Event (MACE)
1) . h/o ischemic heart dz
2) . h/o heart failure
3) . h/o Cerebrovascular disease
4) . IDDM
5) . CRI (creatinine > 2)j
6) Hight risk surgery
Complications of Diabetes of a Mother on the Infant
1) . Respiratory distress syndrome (RDS),
2) . cardiomyopathy, VSD, ASD, TOGV, 1 umbilical artery
3) . Anencephaly, spina bifida, caudal dysplasia, developmental delay
4) . large or small gestational age; hypoglycemia
5) . hypocalcemia, hypomagnesemia, low iron
6) . increased risk for NEC, anorectal fistula
7) . polycythemia, increased viscosity, low platelets, hyperbilirubinemia
8) . shoulder dystocia, Erb’s palsy, clavicular fx,
9) . renal vein thrombosis, hydronephrosis, genesis
Propofol Infusion Syndrome
Occurs after administration of high dose propofol over a long period of time (>4 mg/kg/min > 6hrs)
- unexplained metabolic (lactic) acidosis
- rhabdomyolysis
- hyperkalemia
- hypertriglyceridemia
- hypotension, refractory bradycardia
- sudden arrest
- ARF
- hepatomegaly
Post-op delirium (POD) vs. Post-op Cognitive Dysfunction (POCD)
1) . POD is an acute process (0-5 days post-op), with temporary change in orientation and cognition accompanied by:
- fluctuating loss of conciousness
- inattention
- and/or disorganized thinking
- 75% hypoactive
- mechanism: neuroinflammation, cholinergic inhibition, serotonin deficiency, dopamine activation?
2) . POCD is a mild impairment of memory, concentration and information processing after surgery which persists beyond a few days
- usually oder patients in first few months post-op and then resolves
- persists > 3 months in 13% of elderly
