Angela’s Critical Care Flashcards
What ratio of crystalloid replacement is needed to replace blood loss?
Notes say: 3 to 1
This seems old school and more commonly is about 1.5:1
see UTD: maintain intraoperative normovolemia… replacement of sensible and insensible losses, fluid boluses (typically 250 mL) in volume responsive patients, and replacement of lost blood on a 1.5:1.0 volume basis until a transfusion threshold is met.
What two measurements help establish endpoints of resuscitation immediately postop?
Lactic acid and Base deficit
Which ionotropes are preferred in cardiogenic shock?
Dopamine and dobutamine
Dobutamine is not a vasopressor but rather is an inotrope that causes vasodilation. most frequently used in severe, medically refractory heart failure and cardiogenic shock and should not be routinely used in sepsis because of the risk of hypotension. IT DROPS SVR.
Dopamine has dose-dependent effects - changing the dose of the drug is akin to switching vasopressors. When used for cardiac failure, dopamine should be started at 2 mcg/kg per minute and then titrated. CANNOT GIVE IF PULMONARY EDEMA, MAKES IT WORSE.
Patient with a low systemic vascular resistance (300) and high cardiac output has what type of shock?
Septic
Low SVR, splanchnic vasoconstriction, increased cardiac output characterizes the hyperdynamic phase of septic shock
FYI: SVR is calculated as 80*(MAP-CVP)/CO, where MAP is mean arterial pressure and CVP is central venous pressure. The normal values of SVR range from 800 to 1200 dynes s/cm5
Most important inflammatory mediators of SIRS are?
**TEST QUESTION **
TNF-a, IL-1, and IL-6
Patient with sepsis has SVR 300-400, hypotensive, low/normal PCWP, low urine output. What is least useful drug?
A dobutamine
B dopamine
C levophed (norepinephrine)
D neosynephrine (phenylephrine)
dobutamine (drops SVR)
FYI: SVR is calculated as 80*(MAP-CVP)/CO, where MAP is mean arterial pressure and CVP is central venous pressure. The normal values of SVR range from 800 to 1200 dynes s/cm5
Dobutamine is not a vasopressor but rather is an inotrope that causes vasodilation. most frequently used in severe, medically refractory heart failure and cardiogenic shock and should not be routinely used in sepsis because of the risk of hypotension.
Patient with h/o of CHF presents with low cardiac output, high SVR, pulmonary edema and increased PCWP (28). What drug is most useful?
dobutamine. This is the drug of choice for severe heart failure.
(do not give dopamine with pulmonary edema b/c it can cause pulmonary venoconstriction and worsen the problem)
FYI The normal pulmonary capillary wedge pressure is between 4 to 12 mmHg.
Patient ventilated 100% FiO2 and high PEEP 14, tidal volume 500, mild A-a gradient, desaturating, and unstable. No mention of decreased breath sounds or tracheal deviation initial step in management?
A insert Chest tube without CXR
B start heparin
C VQ scan
start heparin. (basically barotrauma as red herring. work up PE, but treat first)
FYI: physiologic PEEP 4 mmHg. High PEEP —> barotrauma
Also oxygen concentration >60% considered to be potentially toxic and may result in pathologic changes similar to ARDS
High A-a gradients are associated with oxygen transfer / gas exchange problems. These are usually associated with alveolar membrane diseases, interstitial diseases or V/Q mismatch (PE)
What is most sensitive value in preoperative pulmonary function tests in a known COPD patient?
Duplicate
NONE
Lit Review: preoperative spirometry was not predictive of complications following abdominal surgery. PFTs should not be performed routinely in patients undergoing nonresectional surgery. The degree of physiologic impairment (eg, FEV1 or FVC) does not correlate with the risk of postoperative pulmonary complications.
IF ANY, lower preoperative spirometry FVC, NOT FEV1 or FEV1/FVC, may predict PPCs in high-risk patients undergoing laparoscopic abdominal surgery
—
Notes say: (FEV1/FVC <70% would be a very poor perioperative indicator), but this is definition of COPD
Lit review: Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria Classification of severity of airflow limitation in COPD:
- a postbronchodilator FEV1/FVC ratio of <0.7 is considered diagnostic for COPD.
- GOLD system categorizes airflow limitation into stages. In patients with FEV1/FVC <0.7:
GOLD 1 - mild: FEV1 ≥80% predicted
GOLD 2 - moderate: 50% ≤ FEV1 <80% predicted
GOLD 3 - severe: 30% ≤ FEV1 <50% predicted
GOLD 4 - very severe: FEV1 <30% predicted.
What is the most common finding with ARDS?
hypoxemia refractory to o2 therapy was an answer
Defining criteria:
1. Acute onset after defined insult.
2. Bilateral diffuse infiltrates on CXR
3. No evidence of left atrial hypertension, CHF or Pulmonary Artery Wedge Pressure/Pulmonary Artery Occlusion Pressure <= 18 mmHg
4. Impaired oxygenation *** most important criteria
Which of the following is least likely to affect an A-a gradient?
A ARDS
B pneumonia
C PE
D hypoventilation
hypoventilation
What is the effect of high PEEP on central venous pressure?
Decreases venous return, CVP, stroke volume, cardiac output and PCWP
Given that PEEP increases right atrial pressure and, thus, CVP through the increase in intrathoracic pressure, it is generally believed that any increase in PEEP is expected to reduce blood flow by increasing the back pressure to venous return, resulting in a reduction in stroke volume index.
PEEP can decrease cardiac output through a decrease in cardiac preload and/or an increase in right ventricular afterload.
Which of the following is the most appropriate postoperative monitoring for an obese patient with sleep apnea?
A Telemetry
B CPAP
C ICU Admission
D PCWP monitoring
E Continuous pulse ox
Continuous pulse ox
CPAP (most appropriate treatment, but not really a monitor)
What is a measurement that is an estimation of right atrial filling pressure?
CVP, Central venous pressure, which is a measure of pressure in the vena cava, can be used as an estimation of preload and right atrial pressure.
What is a measurement that is an estimation of left atrial filling pressure?
Pulmonary capillary wedge pressure (PCWP) is frequently used to assess left ventricular filling, represent left atrial pressure, and assess mitral valve function.
normal PCWP is 8–12 mmHg
Which measurement estimates preload?
CVP, Central venous pressure, which is a measure of pressure in the vena cava, can be used as an estimation of preload and right atrial pressure.
Notes said PCWP, which is incorrect
ETA: PCWP is the estimate of preload for the left ventricle. CVP is the measure of preload for the right ventricle. If the question doesn’t specifiy, then I would say they meant right. Can discuss further ***
Which measurement would help distinguish cardiogenic and hypovolemic shock?
**TEST QUESTION **
(Duplicate)
Pulmonary capillary wedge pressure
(Aka pulmonary wedge pressure (PWP), pulmonary arterial wedge pressure (PAWP), pulmonary capillary wedge pressure (PCWP), pulmonary artery occlusion pressure (PAOP), or cross-sectional pressure)
Decreased in hypovolemic
Increased in cardiogenic
What does Pulmonary capillary wedge pressure measure?
PCWP is frequently used to assess left ventricular filling, represent left atrial pressure, and assess mitral valve function.
It is measured by inserting a balloon-tipped, multi-lumen catheter (Swan-Ganz catheter) into a central vein and advancing the catheter into a branch of the pulmonary artery. The balloon is then inflated, which occludes the branch of the pulmonary artery and then provides a pressure reading that is equivalent to the pressure of the left atrium.
Which of these is least acceptable in management of a fib?
A Beta blocker
B digoxin
C calcium channel blocker
D adenosine
adenosine (this drug is for SVT)
What is initial pharmacologic treatment for atrial fibrillation?
Beta-blockers and calcium channel blockers are first-line agents for rate control in AF. These drugs can be administered either intravenously or orally. They are effective at rest and with exertion.
Intravenous diltiazem or metoprolol are commonly used for AF with a rapid ventricular response
Which is least likely increase perioperative cardiovascular morbidity/mortality?
A critical aortic stenosis
B age > 70 years
C MI < 6 months
D moderate HTN
E unstable angina
F emergent operation
moderate HTN
Remainder are listed as risk factors within the multifactorial index of cardiac risk:
A critical aortic stenosis: 3 points
B age > 70 years: 5 points
C MI < 6 months: 10 points
E unstable angina: not listed in MICR but is a factor in RCRI
F emergent operation: 4 points
What are the Goldman Multifactorial Index of Cardiac Risk risk factors beginning with the riskiest? (9)
11pts. S3 heart sound or increased jugular venous pressure
10 pts. MI within 6 mos
7 pts. non-sinus rhythm other than PACs
7 pts. >5PVCs/min
5 pts. age >70 yo
4 pts. Emergency procedure
3 pts. Significant aortic stenosis
3 pts. Intra-abdominal procedure
3 pts. poor general health status
What is the most sensitive test for MI?
troponin I
What antibiotic do you use for SBE prophylaxis in PCN allergic patient?
Notes say: Vancomycin if you do it at all but you very rarely should <— this is incorrect based on lit review
AHA/ACC 2007 Guidelines:
- Infective endocarditis prophylaxis for dental procedures is reasonable only for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis.
- Administration of antibiotics solely to prevent endocarditis is not recommended for patients who undergo a genitourinary or gastrointestinal tract procedure.
Abx used: amoxicillin/ampicillin —> keflex/Cefazolin or ceftriaxone if allergic; Azithromycin or clarithromycin or doxy as alternative
Which patients should undergo SBE propylaxis?
Pts w:
- Prosthetic cardiac valve or prosthetic material used for valve repair
- Previous Infective endocarditis
- Congenital heart disease (CHD) including unrepaired cyanotic CHD, palliative shunts and conduits
- Completely repaired congenital heart defect with prosthetic material or device during the first six months after the procedure
- Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization)
For the following procedures:
- Dental procedures involve manipulating gingival tissue or perforating the oral mucosa.
- invasive respiratory tract procedures that involve incision or biopsy of the respiratory mucosa (e.g., tonsillectomy, adenoidectomy).
- Procedures of infected skin, skin structures, or musculoskeletal tissue
B&H:
Enterococci are part of the normal flora of the GI tract and are the primary bacteria from this area likely to cause IE. In patients with high-risk cardiac conditions (e.g., prosthetic heart valve, previous IE, or congenital heart disease) who receive antibiotics for wound prophylaxis, the inclusion of an antibiotic that is active against enterococci may be reasonable (e.g., penicillin, ampicillin, or vancomycin). However, no published studies demonstrate that such therapy will prevent enterococcal IE
Which drug should be stopped prior to contrast administration?
Duplicate
Metformin
can cause life threatening lactic acidosis
Side affects associated with lidocaine overdose?
agitation, dysphoria, confusion, ataxia, seizures, bradycardia from AV block, hypotension, N/V
tinnitus and blurred vision.
CNS depression, unconsciousness and coma.
Max dose (usually 4.5 mg/kg)
With vasoconstrictors such as epinephrine 1:200000 increases to 7 mg/kg
What shifts O2 dissociation curve to right?
What does shift to the right mean?
(Duplicate)
acidosis, CO2, hyperthermia
increase in the partial pressure of carbon dioxide (Pco2), a decrease in pH, or both, the last of which is known as the Bohr effect
rightward shift of the curve indicates that hemoglobin has a decreased affinity for oxygen, thus, oxygen actively unloads.
CADET - face RIGHT. Increased CO2, acidosis, elevated DPG, exercise, temp
left shift indicates increased hemoglobin affinity for oxygen and an increased reluctance to release oxygen
What antibiotic has a high salt load?
ticarcillin disodium and clavulanate potassium
Timentin (be careful with CHF patients)
For the 3.1-gram dosage of TIMENTIN, the theoretical sodium content is 4.51 mEq (103.6 mg) per gram of TIMENTIN
Others of interest: ampicillin, unasyn, metronidazole, moxifloxacin, zosyn
TAZMNUM: kind of like Tasmanian
Tasmanian Devil (Taz) has high blood pressure from the high salt
Ticarcillin disodium
Amp
Zosyn
Metronidazole
Nafcillin
Unasyn
Moxi
On Swan-Ganz, how can you tell when is the pulmonary artery catheter is located in the pulmonary artery?
The pressure wave form shows a dicrotic notch
the location of the catheter can be determined by viewing the pressure measured from the tip of the catheter.
- right atrium (RA), the pressure usually averages <5 mmHg and fluctuates a few mmHg.
- right ventricle (RV), the systolic pressure increases to ~25 mmHg and the diastolic pressure remains similar to right atrial diastolic pressure.
- pulmonary artery (PA), the systolic pressure normally is similar to the right ventricular systolic pressure, but the diastolic pressure increases to about 10 mmHg because of pulmonic valve closure at the beginning of diastole.
- balloon Inflated occludes the PA branch. the pressure in the distal port rapidly falls, reaches a stable lower value that is similar to left atrial pressure (mean pressure normally 8-10 mmHg). The pressure recorded during balloon inflation approximates left atrial pressure because the occluded vessel and its distal branches that eventually form the pulmonary veins act as an extension of the catheter.
See: https://cvphysiology.com/heart-failure/hf008
If you cannot wedge the pulmonary artery catheter into a branch of the pulmonary artery to occlude it, what other measure can you use to approximate PCWP (pulmonary capillary wedge pressure)?
(Duplicate Q)
pulmonary artery diastolic pressure
- pulmonary artery (PA) diastolic pressure is similar to the pulmonary artery wedge pressure and is similar to left atrial pressure (mean pressure normally 8-10 mmHg).
- accurate as long as no pulmonary HTN exists
See: https://cvphysiology.com/heart-failure/hf008
