OA Critical Care part 2 Flashcards
Clearance is:
Fraction of drug eliminated from the body per unit of time.
Volume of Distribution: _____. In other words:
volume that the amount of administered medication would have to occupy, if uniformly distributed to achieve the same concentration as the current plasma concentration. In other words, a larger VD implies that the drug is more dilute than it should be. It essentially describes distribution between plasma and other body tissues.
How does metabolism work in burn patients?
Well first-hypodynamic state (burn shock), followed by hyperdynamic state with anasarca/edema that can last for months.
How does propofol work in burn patients in the hyperdynamic state? Clearance? Volume of distribution?
They usually require more, and their drug clearance is generally increased, and volume of distribution may increase due to enlarged extracellular fluid volume, or due to decreased protein binding.
What happens to albumin and alpha 1 acid glycoprotien in burn patients?
albumin decreases (giving drugs bound to allbumin increased bioavailability), and AA1g increases, giving drugs bound to it decreased bioavailability.
How do PEEP and CPAP affect the extravascular lung water?
No net effect, just redistribution of extravascular lung water to peribronchial and perihilar areas from interstitum between alveoli and endothelial cells
What are indications for TPN:
inability for sufficient nutritional/caloric intake to be absorbed via the GI system (short gut syndrome, small bowel obstruction, acute GI bleeding, pseudoobstruction and high output entercutaneous fistulas)
Pyloric or post pyloric feeds:
no real reason to prefer one over the other unless there’s an anatomic thing.
FENa greater than 3%=associated with: ____. BUN: Cr ration greater than ____ assoc with pre-renal causes of kidney injury. What is the BUN:cr ratio in ATN?
ATN. Cr greater than 20:1, then likely pre-renal. In ATN, BUN: Cr ratio typically less than 15.
Name 3 disadvantages to administering stress ulcer prophylaxis to patients in the ICU?
Increased incidence of PNA, increased incidence of c diff, thrombocytopenia
How does resuscitation for a drowning victim differ than that for a regular victim?
for drowning, you give 2 rescue breaths first (ABC), whereas in other situations, its CAB (circulation (compressions), airway, breathing).
Tell me about the RQ for ppl eating fats, carbs, proteins. What is RQ?
RQ: ratio of CO2 eliminated/O2 consumed. 0.7-1,0 is the range. 1.0=pure carb metabolism. 0.8=proteins, 0.7=pure fat metabolism.
What’s required for a diagnosis of brain death? (FOUR steps):
STEP one: Clinical evaluation: Establish reversible cause of coma Exclude CNS depressants and NMBs Normal temperature (>36) Normal SBP (>100) Single neuro exam after sufficient time period has passed since injury STEP two: Neurologic exam: -unresponsive coma -no cranial nerve reflexes -Apnea (PCO2>60, or >20 over baseline STEP three: -Ancillary testing like EEG or cerebral blood flow study STEP four: -documentation -contact organ procurement
Are spinal reflexes permitted in brain death?
Yes. Spinal reflexes do not mean a patient can not be brain dead
Apnea test must meet which criteria:____. If apnea test can’t be done, what ancillary test is the gold standard and why?
HDS, ventilator adjusted to normocarbia, patient pre-oxygenated with 100% FiO2 for >10 minutes to PaO2>200 and with a peep of 5. If apnea testing can’t be performed, ancillary tests can be done: Cerebral angiography is the gold standard-it is not affected by CNS depressant drugs or hypothermia.
What is needed to make dx of Pul HTN? (3 things)
Right heart cath confirmation of: Resting mPAP >25 mmHg, PCWP/LAP<15, and PVR >3 woods units
Use of insulin therapy in ICU in patients with subarachnoid hemorrhage is associated with :
hypoglycemia
HIT is what, and is characterized by what:
PRO-THROMBOTIC immune mediated disorder where IgG platelet activating abys are formed against Platelet factor 4. Characterized by >50% reduction in platelet count that typically occurs 4-10 days after intiation. of heparin (any type-unfractionated most common)
Type I vs type 2 HIT
Type 1: non-immune mediated. type 2: can lead to catashropic thrombosis.
Key interventionin HIT:
ALL HEPARIN (even flushes) MUST BE STOPPED!
What to do if patient has PE and gets HIT?
Switch to a direct thrombin inhibitor: argatroban.
Why is warfarin contraindicated early in HIT?
Due to risk of warfarin necrosis. because protein c gets depleted first, leading to microthrombosis, and also-warfarin prolongs the aPTT which predisposes to underdosing of direct thrombin inhibitors monitored with aPTT
Explain the rule of nines
In adults: Head is 9% Anterior torso: 18% Posterior torso: 18% Each arm is 9% Each leg is 18%
NMS vs serotonin syndrome: ____. What causes NMS?
NMS: elevated cpk due to rhabdo. NMS risk: those taking antipsychotic and neuroleptic meds that abruptly d/c them.
What causes Serotonin syndrome?
increased serotonergic activity in CNS leading to AMS and agitation. Tx: d/c of serotonergic meds, benzos, and IV cryptoheptadine (serotonin antagonist). Agitation, hyperreflexia, hyperthermia
if you change expiratory time from 1:1 to 1:3 during VCV? Which physiologic changes will happen?
Increased inspiratory flow (makes sense because more volume has to go in with less time
Normal I:E ratio ranges from:
1:2 to 1:4
With higher I:E ratios (1:1 compared to 1:2) shows what as far as peak airway pressures? What other physiologic changes?
Lower peak airway pressures., also-decreased phsyiologic dead space, higher meanairway pressures and increased dynamic compliance.
How much fluid shouldyou give for first 24 hours in burn patients?
4 mL/kg x the percentage of body surface area burned. Give the FIRST half in the first 8 hours, and the 2nd half in the next 16 hours. Only used for 2nd and 3rd degree burns
Lethal triad in trauma
acidosis, coagulopathy, and hypothermia
