General Topic Flashcards
When data is highly skewed, what measure of central tendency is used?
Median
What is standard error?
Refers to the likelihood that the mean and standard deviation of a specific sample of participants reflect the mean and standard deviation of the full population of potential participants
Computed by dividing the standard deviation by the square root of the sample size
What is interquartile range?
Distance between the 25th and 75th% tiles
What is a categorical variable and how should you analyze it?
Variable made of categories that cannot be quantified like blood type
Should be analyzed with non-parametrics statistics
What is a continuous variable and how should it be analyzed?
A variable that gives a score for each subject in a sample and can take on any value on a measurement scale like blood pressure
Should be analyzed with parametric statistics
What is an ordinal variable?
A variable that is recorded on an interval scale from highest to lowest, but does not involve the use of the numerical relationship between the numbers like when a patient rates their pain on a scale of one to 10
What is a parametric test?
Assumes that the data is normally distributed
What is a non-parametric test
Assumes that #DATA is not normal distribution and is typically more stringent
What is the P value?
The probability of the observed result or something more extreme under the no hypothesis, also known as the probability that any particular outcome would have occurred by chance
What is a confidence interval?
Range of values around the sample mean within which a researcher can be certain usually about 95% and it contains the true meaning of the population
What types of analysis to use when both variables are continuous meaning something like blood pressure?
Regression and correlation
What is the regression analysis?
Whether you can predict the value of one variable, which is the dependent variable from the value of another variable, the independent variable
Like a patient’s cholesterol level from the number of years here she has been smoking
What does beta mean when it is reported with regression results?
That is the value by which the independent variable must be multiplied to determine the value of the dependent variable
What type of test can you run when one variable is categorical and one is continuous?
T test and a nova
What is a t test?
Examining whether two groups of participants differ on a variable so comparing findings between a control group and an experimental group
What does a nova involve?
Examining whether two or more groups differ significantly on a variable and it is used when you have more than one experimental group
What is an omnibus F test?
Tells you, whether there is an overall difference between your groups
Wilcoxon signed ranks test
This test functions as a tea test for ordinal variables, examining whether the control group and the experimental group would differ in Payne rat
What is a Pearson chi Square test
Hypothesis test, which may be performed on contingency tables and is used to discover if there is a relationship between two categorical variables
Type one error
Probability of falsely rejecting the null hypothesis
Type two error
Probability of failing to reject the null hypothesis when they’re really is a difference
Power of the study
The statistical likelihood that our researcher will find a significant effect that exists based on the sample size and number of variables
Level one evidence
Randomized control trials or systematic reviews
Level two evidence
Lesser quality, randomized, clinical trials or a cohort study or systematic review of such studies
Level three evidence
Evidence gathered from a well designed quasi experimental study, like a case-control study or systematic review of such studies
Level four evidence
Evidence gathered from well-designed non-experimental study like descriptive studies or case series
Level five evidence
Evidence gathered from expert opinion case reports and clinical examples
What is sensitivity?
Probability that a patient with disease will have a positive result
What is specificity?
Probability that a patient without the disease will have a negative result
What is positive predictive value?
The probability that a patient with a positive test has the disease the more specific test the higher PPV
What is negative predictive value
The probability that a patient with a negative test does not have the disease, the more sensitive attest the higher, the NPV
What supplements should be discontinued to avoid bleeding risk before surgery?
Garlic ginkgo, Balboa ginseng vitamin E saw Palmetto chondroiton omega-3
What is warfarin induced skin necrosis?
It can occur if you start warfarin before heparin because protein C and Shave a shorter half-life than the other vitamin K dependent factors, and this can result to a hypercoagulable state and skin necrosis
What is the most common location of a DVT?
The calf, but the iliofemoral DVTs are the most likely to cause a pulmonary embolus. The left leg is twice as likely as the right because the left iliac vein is compressed by the right iliac artery.
A patient that had a thyroid ectomy three months ago presents for surgery. What should you be cognizant of?
Hypocalcemia you need to check for signs like per oral tingling numbness, prolonged QT on EKG
You might need to do magnesium before before calcium will
What is the difference between corn needle, biopsy and fine needle aspiration
Corn needle gives architecture and fine needle gives cytology
Is higher energy radiation, worse or better for the skin
Better because the higher ionizing potential doesn’t reach until deeper structures
What is a pan coast tumor?
Superior pulmonary sulcus tumor, which can invade the sympathetic chain and cause Horner 🔥🔥🔥 syndrome and it can cause ulnar nerve symptoms
What are the key features of Kylo thorax in its treatment?
Thoracic duct runs along the right side of the chest and crosses over to the left at T4 and T5 to drain into the left. Subclavian vein management includes low-fat diet octreotide, and chest tube.
Surgical ligation can be done if conservative treatment fails
What is the best way to measure alveolar ventilation
PaCO2 gives you the relationship of alveolar ventilation to CO2 production
How to treat elevated intracranial pressure in a trauma patient
Head of bed, elevation
Hypertonic saline
Mannitol
Ventriculostomy
Hyper ventilation
Sedation and paralysis
What is Cushing’s triad?
Hypertension, bradycardia and slow, respiratory rate are suggested of pending herniation in a brain injury patient
What is the most important prognostic indicator of the glass cow coma scale?
Motor
What should you be concerned with in a patient with a posterior knee dislocation?
Popliteal artery injury
Venus air embolus treatment
Turn, patient left lateral decubitus position and supportive care with mechanical ventilation pressures and volume
If a patient with arterial embolism presents, they should be placed flat
What happens if you ligate the carotid artery?
20% of patients will stroke
How does protein binding affect the action of local anesthetic
Local with higher protein binding will have higher contact with the nerve membrane and thus a longer duration of action
How does the Pka affect the action of local anesthetics?
The PKA determines the speed of onset of the nerve block 50% of the local will exist in its basic and cat ionic form
Name three factors that decrease seizure threshold and increase the risk of CNS toxicity
Hypercarbia
Hypoxia
Acidosis
Name two agents that can be used to treat seizures following CNS toxicity with local
Benzo
Sodium thiopental
What is the maximum adult dose of lidocaine without epinephrine?
Five MG per KG
Maximal single dose is 300 mg
What is the maximum adult dose for lidocaine with epinephrine?
Seven MG per KG
500 mg for a single dose
What is the maximum total dose of epinephrine in a healthy adult?
.25 mg
What causes methemoglobinemia?
Oxidation of hemoglobin from its ferric to Ferris form by prilocaine and benzocaine
What are the disadvantages of doing an interscalene brachial plexus block?
Misses, the medial cutaneous nerve, the intercostal break your nerve and ulnar nerve
Not suitable for hand
Complications include a 100% if ipsi phrenic nerve block, Horner 🔥🔥🔥 syndrome, hoarseness, dysphasia, blurred vision and involvement of recurrent laryngeal and cervical sympathetic nerves
What are the disadvantages of a supraclavicular brachial plexus block?
Pneumothorax .4 to 6%
Ipsi phrenic nerve paralysis, 60%
Occasional Horner 🔥🔥🔥 syndrome
Well, suited for long surgery and prolonged postop pain relief
Complete prompt long acting block
What are the disadvantages of the infra clavicular brachial plexus block?
Increase risk of intravascular puncture as the plexus surrounds the subclavian artery at this level
It is a reliable block of muscular cutaneous and axillary nerves
Lower risk of pneumothorax compared to supraclavicular block
More obvious landmarks
What are the disadvantages of the axillary brachial plexus block?
Can miss the muscular cutaneous nerve and the lateral anti brachial cutaneous nerve
Most widely used block and hand surgery
Describe the relationship of the radial ulnar and median nerves to the axillary artery
Radial is posterior
Median is superior
Ulnar is inferior
What are contraindications to using a bier block?
Sickle cell anemia
Severe peripheral vascular disease
Established soft tissue infection
Tumors
What is the best way to measure alveola ventilation?
PACO2
What is Pancoast tumor?
Superior pulmonary sulcus tumor, which can invade the sympathetic chain and lead to Horner 🔥🔥🔥 syndrome or ulnar nerve symptoms
What anatomy is relevant to thoracic outlet syndrome?
Subclavian vein is anterior to the anterior scalene
Subclavian artery and brachial plexus are between the middle and anterior scalene
Most common location of a DVT
Calf but the iliofemoral DVT is more likely to cause a PE
Left leg is twice as likely as right because of compression by the right iliac artery
Cushing’s triad
Hypertension, Brady cardio and slow respiratory rate
Suggest impending herniation in a patient with a head injury
Mechanism of action of steroids in transplants
Inhibit macrophages and genes for cytokines synthesis like IL one and IL6
What is the most important prognostic indicator of GCS?
Motor score
Imiquimod
Toll like 7 receptor for bcc
Most common site for tumor to met s to mandible in female
Breast
Facial plane
nasion to pognion
Concave point @frontonasal suture to the most anterior point on the chin
Cranial base
. Line from midpoint of sella to nasion
Pap
Perforators through adductor Magnus
Found 2 cm posterior gracilis and 8 cm inferior to groin crease
Reverse sural artery flap
Peroneal perforators
Includes rural nerve and saphenous lesser vein
Most common complication is venous insufficiency
Harvested over post. calf @the raphae of gastrocnemius
Granular cell tumor
Thought to originate from Schwann
Invade posterior middle true vocal folds
Can give false +
TX = excision
