General Anesthesia Flashcards
What treatments have been proven to be effective in preventing contrast nephropathy?
- Continuous hemofiltration
- Oral N-acetylcysteine
- Bicarbonate Infusion
How many colony-forming units (CFU) are required from a quantitative bronchoalveolar lavage to make the diagnosis of pneumonia?
10,000 CFU/mL
- For endotracheal aspirates the cutoff is 1,000,000 CFU/mL
- For protected brush specimen the cutoff is 1,000 CFU/mL
What nerves need to be blocked for an awake intubation?
Superior laryngeal nerve (vagus nerve) which supplies sensation to the hypo pharynx (internal branches): epiglottis, base of tongue, supraglottic mucosa, thyroepiglottic joint and the cricothyroid joint.
Glossopharyngeal nerve (IX) which innervates the roof of the pharynx, tonsils, and undersurface of the soft palate.
What is the most common initial manifestation of malignant hyperthermia (MH)?
Increased PetCO2
The initial reduction in core temperature during general anesthesia is cause by?
Redistribution of heat from the core to the periphery
All burn patients should receive 100% oxygen until CoHgb is at what percentage?
Until COHgb is less than 7%.
What are the innervations (afferent and efferent) for the oculocardiac reflex?
Afferent: trigeminal nerve
Efferent: vagus nerve
What coagulation factors are produced outside of the liver?
Factor VIII and von Willebrand are “endothelium-derived procoagulant factors” and are increased in cirrhosis
An extrahepatic source of factor VII has also been identified
What area of the brain is effected by Parkinson’s disease? What are the symptoms?
The fundamental lesion in Parkinson’s is in the basal ganglia.
Classic symptoms:
drawn face
fixed expressions
lead pipe rigidity
nonintentional tremor which diminishes with activity
initiation of movement is difficult as is termination
What are the signs and symptoms of carcinoid syndrome and how is it diagnosed?
Carcinoid tumors release vasoactive peptides into the systemic circulation causing symptoms when the tumor metastasizes from its site of origin (usually the appendix or ileum) to the liver or when its venous drainage returns to the heart bypassing the liver.
Hormones released include: SEROTONIN, histamine, and kinins
Symptoms include: cutaneous flushing (sweating), bronchoconstriction, hypotension, diarrhea
Signs: urinary 5-HIAA levels (a metabolite of serotonin)
right sided heart failure, tricuspid regurgitation (common) or stenosis, pulmonary regurgitation/stenosis (right-sided fibrotic endocardial lesions)I
What is the treatment for carcinoid syndrome?
Octreotide (a somatostatin analogue) is the mainstay of peri-op tx. It binds to SSTR subtypes 2 & 5 inhibiting secretion of various peptide hormones (i.e. serotonin) (t 1/2 1-3 minutes)
Subcutaneous administration with max plasma concentration after 30 mins. Elimination half-life of 1.5-2 hours.
Elimination in 2 phases with half-lives of 10 and 90 minutes respectively
Cyproheptadine is a serotonin antagonist used in serotonin syndrome.
What are the criteria for diagnosing pre-renal acute renal injury (ARI)?
Urine osmolality > 500 mOsm/kg Bland (hyaline casts) sediment Urine Na+ < 10 mEq/L (due to activation of the renin angiotensin aldosterone system (RAAS) FENa < 1% No to minimal amount of protein in urine
How is total lung capacity(TLC) affected in patients with obstructive lung disease? FVC? FEV1/FVC ratio? FEF 25% to 75%?
TLC is normal or increased due to air trapping and increased residual volume (RV)
Forced vital capacity (FVC) is also increased or normal
FEV1/FVC ratio is decreased (since FEV1 is decreased)
FEF 25% - 75% is decreased due to airway resistance
How does restrictive lung disease effect TLC? FVC? FEV1/FVC ratio?
Restrictive disease is a proportional decrease in ALL lung volumes, which results in a normal FEV1/FVC ratio
Decreases in TLC, FVC, FEV1, and FRC
What are the increased anesthetic risks associated with patients with Down syndrome? What disease(s) are usually associated with these patients?
They have an increased risk of airway problems: macroglossia, atlantoaxial instability, subglottic stenosis, and OSA.
They also have an increased risk of HYPOthyrodiism, polycythemia at birth, and diabetes mellitus.
In liver transplants, what are the possible physiologic derangement that may need to be addressed at the time of reperfusion?
1) With the removal of the portal vein clamp and reperfusion of the transplanted liver, the residual cold, potassium-rich preservative solution from the donor liver enters the vena cava and boluses directly to the recipient’s heart.
Prophylactic administration of sodium bicarbonate and calcium may ameliorate the hemodynamic consequences of hyperkalemia
2) Subsequent removal of all naval clamps results in reperfusion syndrome in 30% of recipients; hemodynamic instability with hypotension due to vasodilatation is treated with epinephrine or phenylephrine (norepinephrine, epinephrine, vasopressin infusions) and 3) pulmonary hypertension with nitric oxide or nitroglycerine
At this point, a immunosuppressant steroid is administered, usually methylprednisolone.
What is the first drug choice in treating RV failure with elevated PA pressures following reperfusion in a liver transplant?
Epinephrine is the first drug choice to improve RV contractility and increase systemic blood pressure (primary focus)
Nitric oxide would not increase the systemic blood pressure; nitroglycerin could not be the sole agent (although both are useful in decreasing PA pressure)
What surgical procedures are associated with an increased risk of PONV?
Septal nasal submucosa resection Tonisllectomy and adenoidectomy Rotator cuff repair Knee arthroscopy Laproscopic cholecystectomy Lumpectomy
What is the storage life of red blood cells preserved with CPDA-1 and ADSOL?
42 days
ADSOL (AS-1) is a preservative added to CPD-packed red blood cells which is used to increase the shelf-life of the unit
*Nutricel (AS-3) and Optisol (AS-5) are other common solutions that will preserve RBCs to 42 days.
What is the storage life of red blood cells preserved with CPD, ACD, and CP2D alone?
21 days stored at 1-6 degree Celsius
What is the storage life of red blood cells preserved with CPDA-1 alone?
CPDA-1 solution increases the shelf-life to 35 days
What is the storage life of red blood cells that are frozen?
up to 10 years
How does activated protein C aid in the treatment of septic shock?
Patients with septic shock show clinical or subclinical manifestations of intravascular disseminated coagulation with consumption coagulopathy. Recombinant activated protein C can be given to patients with septic shock to modulate sepsis-induced coagulopathy.
What is the most common transfusion-related infection in the US?
Cytomegalovirus (CMV)
The incidence of transfusion-transmitted CMV disease is dependent on the type of blood product (RBC vs. platelets) and the use of leukoreduction (CMV is latent in cells of the monocyte/macrophage lineage and it is these cells that can support CMV replication)
2.4% vs. seronegative blood components
What are the risk of acquiring West Nile virus vs. HIV vs. HTLV vs. Hepatitis C virus following blood transfusions?
West Nile Virus: 1:1 million
Hepatitis C: 1:1.2 million
HIV: 1:1.5 million to 1:3 million
HTLV: 1:3 million
Following a parathyroidectomy, when would postoperative hypocalcemia reach a nadir? What would the symptoms be?
3 to 7 days after surgery
Symptoms of hypocalcemia include: spasms cramps seizures stridor/apnea (if severe)
What are the symptoms of hypercalcemia?
Stones (renal function)
Bones (pain)
Groans (abdominal pain, nausea/vomiting)
Throans (polyuria, decreased volume status)
Psychiatric overtones (depression, anxiety, cognitive dysfunction)
What are the hallmark signs associated with fat embolism?
Petechial rash over the chest is pathognomonic for fat embolism
Decreased room air saturation
Decreased end-tidal carbon dioxide levels
Intraalveolar hemorrhage can occur in the first 24-48 hours
Diabeties Insipidus (DI) vs. Syndrome of Inappropriate ADH (SIADH); presentation, clinical signs
Both are common postoperative complications of pituitary surgery
DI usually presents as a low blood pressure with excessive urine output
- elevate serum sodium ( >146 mEq/L)
- elevated serum osmolality
- possible pre-renal picture with BUN:creatinine ratio (although serum creatinine is unaffected)
SIADH
- low serum osmolality ( < 270 mOsm/L)
- high urine osmolality (> 450 mOsm/L)
- normal to low serum sodium
How do you determine the normal PaO2 of a patient based on their age?
PaO2 = 102 - age/3
How does lithium effect ADH release?
It inhibits ADH release
What percentage decrease in blood volume must occur to trigger ADH release?
5-10% drop
Increases in what plasma levels occur in the body’s response to surgical stress?
Increase in plasma levels of:
Cortisol Renin ADH Catecholamines Endorphines
(Regional anesthesia, however, may block part of the stress response probably by blockade of neural communications from the surgical site)
How much is vital capacity and FRC changed in laparoscopic surgery? How long does it take for levels to return to normal values?
Vital capacity and FRC may be reduced by 20-40% postoperatively and may not return to normal values until 2-3 days after surgery.
What are the changes in body composition (muscle and fat) associated with aging?
Loss of skeletal muscle Increase in body fat (especially visceral & intramuscular fat) Basal metabolism declines Total body water is reduced Small decrease in albumin levels
What happens to FRC in the elderly?
FRC increases due to the increase in RV (FRC = RV + expiratory reserve volume)
In which direction does the hemoglobin dissociation curve shift with carbon monoxide poisoning?
It impairs oxygen unloading to the tissues and shifts the curve to the left.
Describe the acid-base or electrolyte abnormalities found in a patient with uremic syndrome.
Clinical features
Uremic syndrome is an extreme from of chronic renal failure, which occurs when GFR decreases to less than 10% of normal.
Clinical features: nausea/vomiting, fatigue, anorexia, weight loss, muscle cramps, pruritis, and change in mental status.
Patients often present with elevated phosphate and magnesium levels as excretion of each decreases with progressive renal failure.
Hyperchloremic metabolic acidosis
Criteria necessary to declare brain death
1) Patient must be comatose with neither spontaneous movement nor response to painful stimuli
2) A lack of brain stem activity should be confirmed by assessment of the brain stem reflexes and apnea test
Describe an apnea test
An apnea test is used to confirm the lack of brain stem activity
The patient is pre oxygenated with 100% oxygen for 10 minutes, the PaCO2 is confirmed in the normal range, and the patient is administered oxygen for 10 minutes.
The patient is then disconnected from the ventilator and blow-by O2 is administered with a T-piece
After 7-10 mins, a PaCO2 is measured:
if greater than 60 mmHg, and the patient’s abdomen and chest have NOT moved, the apnea test is positive
What are examples of brainstem reflexes?
Pupillary response to light Corneal reflex Oculocephalic reflex Oculovestibular reflex Gag & Cough reflex Facial motor response
Equation for Mean Arterial Pressure (MAP)
MAP = DBP + [1/3(SBP - DBP)
In what population is FRC increased?
The elderly
FRC increases with age, but only slightly after 50 years.
What is the leading cause of death in patients with multiple sclerosis (MS)?
Bronchial pneumonia due to cranial nerve involvement causing dysphagia
What are some predictive factors of difficult mask ventilation?
Obesity Age > 60 years Mallampati III or IV view Snoring Beard
What is the hallmark finding of COPD based on PFT/Spirometry?
Decreases FEV1/FVC ratio
What is Functional Residual Capacity (FRC)?
ERV + RV
What Vital Capacity (VC)?
IRV + TV + ERV
or
IC + ERV
What PFT increases with COPD? Why?
Total lung capacity mainly due to increased Residual Volume
What is DLCO? How is it used?
DLCO is the CO Diffusion Capacity
It is an independent predictor for risk of post-op complications and reflects alveolar membrane integrity and pulmonary capillary blood flow
What is a low DLCO indicative of?
Low DLCO implies significant emphysema and reduced pulmonary capillary vascular bed
(It can be paradoxically elevated in patients with severe COPD and is indicative of RVH)
How do mediastinal masses effect the flow volume loop?
Mediastinal masses are an example of INTRATHORACIC LESIONS which show BLUNTING OF EXHALATION
How do extra thoracic lesions effect the flow volume loop?
EXTRATHORACIC LESIONS show BLUNTING OF INHALATION
How do fixed lesions effect the flow volume loop?
Fixed lesions such as tracheal stenosis, show BLUNTING OF BOTH (inhalation and exhalation) limbs
What is the formal definition of ARDS?
PaO2/FiO2 < 200
How will increasing altitude affect the alveolar O2 concentration?
It will decrease the alveolar O2 concentration
How is the anion gap calculated?
Na+ - (HCO3- + Cl-)
Normal is 8-12
What are the basic causes for a rightward shift of the oxyhemoglobin dissociation curve?
Decreased pH (acidic environment) or Increased H+
Increased temperature
Increased DPG
Increased PCO2
Smoking cessation improves what factor immediately (12 hours )?
It decreases CO levels
What does ventilation do as one moves to more dependent areas of the lung (from West zone 1 to 3)?
Ventilation increases
Compliance of the alveoli is highest in which West Lung Zone?
Zone 3
What are the 5 causes of hypoxemia? Which ones demonstrate a normal A-a gradient?
Hypoventilation Low FiO2 Diffusion limitation Shunt Ventilation-perfusion mismatch
Normal A-a gradient is shown with hypoventilation and low FiO2 causes
Describe uremic syndrome and the electrolyte abnormalities seen in uremic syndrome. What are its clinical features?
Uremic syndrome is an extreme form of chronic renal failure, which occurs when GFR < 10% of normal.
Clinical features: N/V, fatigue, anorexia, weight loss, muscle cramps, pruritis, and change in mental status
Electrolyte abnormalities include: HYPERphosphatemia HYPERmagnesemia HYPERkalemia (multifactorial) HYPERchloremic metabolic acidosis
Symptoms of toxic multi nodular goiter
Classic triad of goiter, exophthalmos, and pretibial myxedema
Symptoms include:
- Sinus tachycardia or atrial fibrillation
- increased sensitivity to catecholamine-induced arryhthmias
- increased cardiac output and pulse pressure
- Cardiac failure
What are the clinical features of a thyroid storm?
Clinical features:
- Fever
- Acidosis
- Tachycardia
- Arrhythmia
- HTN or Hypovolemic shock
- Cardiac failure
- Agitation
- Tremor
- Coma
- Vomiting
- ABDOMINAL PAIN
- Diarrhea
How does hypoxemia effect intraocular pressure?
Hypoxemia will raise the IOP because the choroidal arterioles respond by vasodilating raising IOP and volume
What are the characteristic signs of autonomic hyperreflexia?
Hypertension and Bradycardia
What are the signs/symptoms of Serotonin Syndrome that differentiate it from Malignant Hyperthermia?
Unlike MH, the arterial blood gas analysis, ETCO2 and respiratory rates are often normal when the temperature is elevated.
It is characterized by agitation, confusion, hyperreflexia, hypertension, hyperthermia, and tachycardia.
How is Serotonin Syndrome distinguished from Neuroleptic Malignant Syndrome?
Neuroleptic Malignant Syndrome has elevated creatinine phosphokinase (CPK) and bradykinesia, absent in Serotonin Syndrome.
What is the treatment for Serotonin Syndrome?
First, stop the offending drugs, followed by observation for 24hrs, IV fluids, and benzodiazepines to decrease agitation, seizure-like movements, and muscle stiffness.
Cyprohepatdine, which blocks serotonin production, and may be used in treatment.
In regards to liver function tests ALT and AST, which one is most sensitive in assessing the degree of liver dysfunction?
ALT is more sensitive than AST in assessing the degree of liver dysfunction
What is the AST/ALT ratio that indicates alcoholic liver disease?
a ratio > 2
Conditions associated with a lower DLCO
Impaired gas exchange:
COPD Heart failure Anemia Sarcoidosis Asbestosis Tuberculosis
Conditions that are associated with an increased DLCO
Asthma Polycythemia L to R intracardiac shunting Exercise Pulmonary hemorrhage
What electrolyte abnormality increases MAC of volatile anesthetics?
HYPERnatremia
How to calculate expected baseline PaO2
Normal PaO2 = 102 - age/3
What are the typical signs/symptoms of Cushing’s syndrome?
Volume overload Hypertension Glucose intolerance HYPERglycemia HYPOkalemic metabolic alkalosis
Central obesity Moon facies Buffalo hump Facial plethora Skin thinning Proximal muscle weakness Osteopenia
Chronic bronchitis vs. emphysema
Chronic bronchitis is characterized by erythrocytosis and a more elevated Hct compared to emphysema.
- CB also develops pulmonary HTN leading to cor pulmonale.
- “Blue bloaters” - copious sputum production, ELEVATED PaCO2, NORMAL elastic recoil, and INCREASED airway resistance
Emphysema patients are referred to as “Pink puffers”
- chronic coughing with exertion, scant sputum production, NORMAL Hct, NORMAL or DECREASED PaCO2, DECREASED elastic recoil of the lungs, NORMAL to slightly INCREASED airway resistance
- they develop cor pulmonale late, if at all
What would a urinalysis of a pre-renal acute renal injury (ARI) look like? (osmolality, sediment, urine Na+, FENa)
Urine osmolality > 500 mOsm/kg
Sediment = hyaline casts (bland)
Urine Na+ < 10 mEq/L
FENa < 1%
What are the 3 main divisions of the autonomic nervous system? Describe
1) Sympathetic - thoracolumbar, short preganglionic path with synapse near the vertebral bodies
2) Parasympathetic - craniosacral, long pregnanglionic path with synapse near the effector organs
3) Enteric - the gut can function without CNS input
What side effects are associated with TURP irrigation solutions? Glycine, Distilled water, Sorbitol, Mannitol, and Lactated Ringers
Glycine is responsible for postop visual disturbances (transient post visual syndrome)
Distilled water is profoundly hypotonic and causes HYPOnatremia
Sorbitol cause HYPERglycemia and lactic acidosis
Mannitol causes osmotic diuresis and acute intravascular volume expansion
LR can cause metabolic alkalosis due to the metabolism of lactate to bicarbonate by the liver
s/p Parathyroid surgery, when do calcium levels reach a nadir?
3-7 days after surgery
What drugs should be avoided in patients with Guillan Barre Syndrome?
Indirect sympathomimetics due to the up regulation of post-synaptic receptors (an exaggerated response can be elicited)
Succinylcholine
Nondepolarizing muscle relaxants should be used with caution due to hypersensitivity
What muscle relaxant should be avoided in patients with Carcinoid tumors?
Succinylcholine because it has the propensity to cause a histamine release 2-3 times the ED95 dose
What are the diagnostic criteria for Obesity Hypoventilation Syndrome?
BMI > 30kg/m^2
Awake arterial hypercapnia (PaCO2 > 45 mmHg)
No other cause for chronic hypoventilation
Abnormal polysomnography findings that include hypoventilation with nocturnal hypercapnia with/without obstructive apnea or hypopnea events
What are the risk factors associated with Obesity Hypoventilation Syndrome (OHS)?
Male sex ages 50-70 years History of chronic fatigue Mood disorders Morning and Nocturnal headaches Dyspnea with minimal exertions Hypersomnolence
During laryngospasm, what is the afferent limb of the glottic closure reflex?
The afferent limb is primarily mediated by the INTERNAL branch of the SLN while the efferent limb is mediated by the RLN
What part of the respiratory system does NOT participate in gas exchange?
The terminal bronchioles are part of the conducting airways, which begin at the oropharynx and end at the terminal bronchioles. No gas exchanges occur in the conducting airways.
What are calcium deposits in the articular cartilage indicative of?
Characteristics of PSEUDOgout
[Mainly manifests itself as monarticular and usually involves the knee joints]
What is the hallmark finding in gout?
Gout is marked by deposition of monosodium rate monohydrate (top) in the joints as a result of chronically elevated uric acid.
How does hypothermia increase MAP?
Hypothermia causes an increase in SVR by vasoconstriction and also causes an increase in viscosity, which will cause blood pressure to increase
How much will pH change for every 10 mmHg change in PaCO2?
0.03 units for every 10 mmHg change in PaCO2
What is the normal FRC in an adult male?
Approximately 2.5 L or 35 mL/kg
During acute normovolemic hemodilution, removed blood can be stored at 1-6 degrees Celsius for how long? at room temperature?
24 hours at 1-6 degrees Celsius
8 hours at room temperature
What is the normal vital capacity in a healthy adult?
60-70 mL/kg
What is epicritic sensation?
It is non-painful sensation such as temperature, touch, pressure, and proprioception
What is protopathic sensation?
It is painful stimulation and can be further divided into nociceptive and neuropathic.
What are some associated pathologies of Systemic Lupus Erythematosus (SLE)?
- atlantoaxial subluxation (9%)
- chronic pulmonary fibrosis from repeated inflammatory insults results in a restrictive lung pattern
- tracheal stenosis (~30%)
Define hyperpathia
Exaggerated pain in response to nociceptive stimuli
Define hyperalgesia
Increased sensitivity to pain
Define Paraesthesia
abnormal sensation without an apparent stimulus
Define Neuralgia
Pain in the distribution of nerve fiber or bundle
Define Allodynia
Perception of non-noxious stimuli as painful
What fruit allergies are associated with a latex allergy?
Allergies to bananas and kiwi display a higher propensity to latex allergy
What is Fick’s law of diffusion? Describe
Diffusion of gas = [A x D x (P1-P2)] / T
where, A = surface area, D = solubility/sq root of molecular weight of gas, P = partial pressure of each side of the tissue, T = tissue surface
Diffusion of a gas across a surface of tissue is increased as the tissue surface area increases.
Diffusion is increased when molecular weight of the gas is decreased because the diffusion constant for the specific gas increases as solubility increases.
Diffusion of a gas increases as the partial pressure difference on each side of the tissue increases, but it decreases when tissue thickness increases.
Cushing’s triad
Hypertension
Bradycardia
Irregular breathing pattern
Laminar flow is affected by what gas characteristic?
Gas viscosity
Turbulent flow is affected by what gas characteristic?
Gas density
atomospheric pressure effects this
When does the risk of subglottic tracheal stenosis increase with endotracheal intubation?
After the ETT has been in place for 2-3 weeks
How do the vocal cords look after bilateral injury to the recurrent laryngeal nerve (RLN) vs. bilateral injury to the vagus nerve?
PARTIALLY ADDucted vocal cords occur with bilateral RLN injury due to unopposed crycothyroid muscle.
Bilateral injury to the vagus nerve will eliminate motor innervation to the larynx, causing FULLY ABDUCTED vocal cords.
What is the desirable value for maximal oxygen consumption (VO2 max) in pre-op evaluation of a patient for lobectomy?
VO2 max > 20 mL/kg/min
What anesthetic decreases the incidence of DVTs?
Neuraxial techniques desserte the incidence of DVTs by improving microvascular circulation by sympathectomy induced vasodilation
What organs make up the vessel-rich group?
Brain, liver, kidney, and heart
What electrolyte abnormality can cause an increase in serum ionized calcium concentration?
Acute HYPOmagnesium will result in an increase in parathyroid hormone which will increase serum iCa
What are patients with neurofibromatosis at risk for?
Neurofibromatosis (von Recklinghausen’s disease) is also associated with multiple endocrine neoplasia (MEN) 2B which includes medullary carcinoma and pheochromocytoma.
Patients with pheochromocytoma display an exagerrated response to indirect acting vasopressors due to an abnormally large depot of catecholamines
They also have abnormal responses to both depolarizing and nondepolarizing neuromuscular blocking agents
How does hypercalcemia effect MAC?
Decreases MAC
How do Hgb concentration, exercise, PCO2, position, and alveolar fibrosis effect DLCO?
1) Hgb concentration is directly proportional to DLCO (decreased Hgb leads to decreased DLCO)
2) Exercise will increase DLCO 2-3 times normal levels
3) PCO2 is directly proportional to DLCO (an increase in PCO2 will lead to increased DLCO)
4) Supine position leads to increased DLCO
5) Alveolar fibrosis (e.g. sarcoidosis, asbestosis, O2 toxicity pulmonary edema) will decrease DLCO
What percentage of blood volume must be lost to trigger ADH release?
5-10% decrease
What is an increase in peak inspiratory pressure (PIP) with no change in plateau pressure indicative of?
It signals an increase in airway resistance/inspiratory gas flow rate
- bronchospasm
- kinked ETT
- foreign body aspiration
- airway compression
- ETT cuff herniation
What is an increase in both peak inspiratory pressure (PIP) and plateau pressure indicative of?
It implies an increase in tidal volume or an decrease in pulmonary compliance
- pulmonary edema
- pleural effusion
- ascites
- peritoneal gas insufflation
- tension pneumothorax
- endobronchial intubation
What factors predict poor outcomes (desaturation) in one lung ventilation?
1) Pre-existing RV/TLC ratio > 50%
2) Right sided thoracotomy
3) Poor PaCO2 on two lung ventilation
4) Surgery in the supine position
5) > 70% of blood flow is to the diseased lung
What is a low Reynolds number indicative of?
Laminar flow
What effect does hyperparthyrodism have on phosphate levels? What occurs?
Hyperparathyroidism leads to low phosphate levels, which increases GI absorption of calcium —> stimulating the breakdown of bone —> impairing the uptake of calcium from bone.
What is the fastest rate at which a patient with hypernatremia, should be corrected?
It should not be decreased faster than 0.5 mEq/L/hr
When should initiation of TPN be considered in patients in who enteral feeding is not possible.
8 days
noted fewer infections than when initiated earlier
What are the 5 classes of pulmonary hypertension as classified by the World Health Organization?
Pulmonary HTN is classified by the mechanism of disease:
1) Pulmonary arterial HTN [idiopathic pulmonary HTN]
2) Pulmonary venous HTN [caused by left heart disease]
3) Pulmonary HTN associated with hypoxemia
4) Chronic thromboembolic pulmonary HTN
5) Miscellaneous [pulmonary HTN with unclear and/or multifactorial mechanisms
What are the standard phases of immunosuppression?
1 )Induction - complete paralysis of the cellular immune system with relatively little regard for medication side effects
2) Maintenance - most regimens consist of steroid plus a calcineurin inhibitor and possibly an anti proliferative agent (e.g. sirolimus)
3) Anti rejection therapy - usually consist of high-dose steroids, or anti-lymphocyte antibodies, or both
What is an ABSOLUTE contraindication to ECT?
Pheochromocytoma
