critical care Flashcards
what tidal volume should be used in cases of ARDS
4-6ml/kg of ideal body weight
indications for operative fixation of severely displaced rib fractures
- those undergoing thoracotomy for intrathoracic injuries
- progressive pulmonary deterioration despite aggressive nonoperative management
- those unable to be weaned from vent after resolution of pulm contusions
- significant chest wall deformity and nonunion fractures
parkland formula
4ml/kg per % TBSA; give first half over 8 hours; give second half over 16 hours
example 80kg male with 80% tbsa: 80kgx4x80%=25600
25600/2= 12800: give this over 8 hours, then an additional 12800 over 16 hours
what chest tube output for hemothorax suggests need for thoracotomy?
1L of blood output after immediate CT placement or 200-300 cc/hr over 4 hours
what is an adequate UOP for a burn patient?
adults: 0.5mg/kg/hr
pediatrics: 1.0mg/kg/hr
what type of fracture is often associated with hollow viscus, mesenteric and solid organ injuries?
chance fracture
most effective means of rewarming patients with severe hypothermia?
cardiopulmonary bypass and ecmo
CO2 pneumoperitoneum can cause increased pCO2 which can result in ______ after extubation.
hypoventilation-related respiratory failure
true or false: septic shock responds well to vasopressors
false
type of shock resulting in hypotension from failure of vascular smooth muscle to constrict, partly from upregulation of iNOS and NOS2 in the vessel wall
septic shock
what patient population should never get a transvenous pacemaker?
pts with mechanical valves
oculovestibular reflex:
test for brain death; instill cold saline in right ear elicits nystagmus with fast beat to left (this is normal and negative for brain death)
electrolyte indication for delaying insulin therapy in DKA:
hypokalemia less than 3.3
physiologic effects of abdominal compartment syndrome (intraabdominal hypertension/IAH):
decreased CO; decreased venous return; increased intrathoracic pressure due to diaphragm being displaced cephalad; increased airway pressures; inadequate renal perfusion
respiratory quotient equation:
VCO2/VO2
respiratory quotient of fat
0.7
respiratory quotient of glucose
1.0
respiratory quotient of protein
0.8
respiratory quotient suggestive of over feeding
> 1.0
CONTROL trial findings for recombinant factor VIIa(rFVIIa)
no mortality benefit in ongoing bleeding; did decrease RBC and FFP transfusion needs
what does dabigatran prolong
aPTT; but not in a dose dependent fashion; direct thrombin inhibitor
risk factors for postop delirium:
ASA 4 or higher; intraop transfusion of >1L; BMI <18; age >70; cognitive impairment with MMS exam score <25
CRASH trial TXA results:
safe in patients with TBI; treatment within 3 hours of death with TXA reduces head-injury related death
heart rhythms that necessitate defibrillation in ACLS:
Vfib, VTach
most common cause of acute liver failure in US
acetaminophen toxicity
how do you assess for intraabdominal hypertension?
bladder pressure at the end of expiration
EKG changes of hypomagnesemia:
wide QRS, transition from peaked T waves to dampened T waves; prolonged PR interval; polymorphic ventricular tachycardia
what drug can be given for cardiogenic shock after cabg?
dobutamine (inotrope) with goal CI >2
pharmacologic properties of dobutamine:
catecholamine that acts on beta adrenergic receptors; enhances myocardial contractility with modest (mild) change in HR
contraindications to PEG placement
massive ascites; severe malnutrition; life expectancy <30 days
hemodynamic changes of septic shock:
decreased CVP, decreased PCWP, increased CI, decreased SVR
types of distributive shock:
neurogenic, anaphylactic, septic; all with decreased SVR
contraindications to succinylcholine:
any patient who is hyperkalemic or at risk for hyperkalemia; prolonged immobilization, upper or lower motor neuron disorders, burn patients
HD changes of acute spinal cord injury:
bradycardia, hypotension, decreased CO, decreased PVR, cardiac dysrhythmias
characteristics of type 1 hepatorenal syndrome:
doubling of Creatinine within 2 weeks and creatinine of at least 2.5; urine sodium is low; no improvement with albumin; frequently follows precipitating event; if untreated mortality in 2 weeks; not associated with ascites
characteristics of type 2 hepatorenal syndrome:
less rapid deterioration than type 1; associated with diuretic resistant ascites; 4-6 month mortality if untreated
initial treatment of hypotension from neurogenic shock
fluids; maintain MAP 85-90
should steroids be used for septic shock?
only if fluids and vasopressors are unable to restore hemodynamic stability
rhythms for synchronized cardioversion:
SVT, afib, aflutter, atrial tachycardia, monomorphic VT with pulses
cardiogenic shock HD changes:
increased CVP, increased PCWP, decreased SVO2, decreased CO, increased SVR
what respiratory condition has improved mortality with administrations of early neuromuscular blockade (cisatracurium) for 48 hrs
ARDS
sympathetic fibers of the heart exit the spinal cord at what level
T1-T4; injuries at or above this cause decreased myocardial contractility and HR
refeeding syndrome electrolyte abnormalities:
hypokalemia, hypophosphatemia, hypomagnesemia, hyponatremia, and thiamine deficiency
pts with afib for over 48 hours or unknown amount of time should be treated with what?
rate control, then anticoagulation
pressor of choice for pts with anaphylactic shock and refractory hypotension despite immediate and adjunctive treatment with crystalloid
epinephrine
what drug has been shown to reduce postop pain and opioid consumption?
dexmedetomidine (IV)
diagnostic test to confirm anaphylaxis
total serum tryptase 1 hr after sx onset
in what time frame after prehospital CPR can a resuscitative thoracotomy still be performed
within 10 minutes for blunt; within 15 minutes for penetrating
first hemodynamic change seen with hemorrhage:
narrowed pulse pressure
total amount of air that can be expelled after maximal inhalation:
vital capacity
inspiratory reserve volume + tidal volume + expiratory reserve volume
first physical exam finding of hemovolemic shock:
cutaneous hypoperfusion
heparin mechanism of action:
activates antithrombin III which antagonizes thrombin and factor Xa
amount of air moved in a normal breath
tidal volume
amount of air left after maximal exhalation
residual volume
amount of air that can additionally be expired from lungs by maximal effort after normal expriation
expiratory reserve volume
treatment of hepatorenal syndrome:
liver transplant is only treatment
second line vasopressor to norepinephrine in increasing blood pressure
vasopressin (also used for bleeding esophageal varices)
refeeding syndrome causes severe electrolyte and fluid shifts leading to cardiac, pulmonary, muscular, GI, neuro and heme complications because of what surge?
insulin surge in response to carbs causing extracellular K, Mg, and PH to move intracellularly
most fatalities from refeeding syndrome are from what type of complications?
heart failure and arrhythmias (cardiac)
what type of organisms cause most empyemas:
anaerobic
what medication is used in brain death patients to protect organs from diabetes insipidus?
vasopressin
type 1 hypersensitivity reaction:
binding of antigens to IgE causes mast cell and basophil degradation; e.g. anaphylaxis
type 2 hypersensitivity reaction:
immunoglobulins attach to surface antigens with subsequent complement fixation; autoantibodies develop to cell surface receptors; delayed after exposure to antigens; eg. Graves disease
type 3 hypersensitivity reaction:
circulating antigen-antibody immune complexes with subsequent complement fixation leads to deposition in vessels, joints, and kidneys; eg. serum sickness
type 4 hypersensitivity reaction:
cell-mediated immunity leading to local injury when antigen present; e.g. contact dermatitis
in patients without a brain injury with massive bleeding and an elevated INR, what is goal BP until major bleeding has been stopped?
SBP 80-90
true or false: PCC is superior to FFP in rapid reversal of vit K antagonists
true
TXA should be given within ___ of injury in bleeding trauma patients
3 hours
dobutamine effects:
beta 1 adrenergic receptors at low dose which increases contractility; beta 2 adrenergic receptors at high dose which has vasodilatory effect
what is delta pressure in compartment syndrome:
diastolic pressure minus compartment pressure; used to dx compartment syndrome needing fasciotomy between 20-30
vasopressin mechanism:
vasoconstriction via V1 receptor; no cardiac effect
leading cause of death due to hospital acquired infection:
pneumonia
substance used in trauma to inhibit fibrinolysis and reduce surgical blood loss; decreases mortality if given within 1 hour of presentation:
transexamic acid
true or false: TXA increases risk of PE or VTE
false
prothrombin complex concentrate contains what factors:
factor II, VII, IX, X, protein C, protein S; indicated for urgent reversal of vitamin K antagonists like warfarin; does not increase venous thromboembolism
pts with severe frostbite who present within 24 hrs of cold injury may be a candidate for what medical therapies:
tissue plasmingen activator (tPA) thrombolysis, prostacyclin, or both
what should be given to reverse rivaroxaban quickly (factor xa inhibitor)?
PCC
physiologic changes of pregnancy:
increased tidal volume; decreased PaCO2; increased blood volume; decrease LE sphincter competency; increased coagulation; decreased GB emptying
test used to detect occult placental hemorrhage in pregnant trauma pt
kleihauer betke test
crystalloid resuscitation in pediatric trauma:
20cc/kg
blood resuscitation in pediatric trauma:
10cc/kg
hemodynamic response of elderly in trauma differ in that they have ___ cardiac function, ___ after load, ___ sensitivity to catecholamines, and ___ robust sympathetic response
decreased cardiac function, increased afterload from atherosclerosis, decreased sensitivity to catecholamines, and less robust sympathetic response
True or false. A short course of 7-8 days of abx is as effective as 14-15 days of abx for VAP.
true
Cause and symptoms of proprofol infusion syndrome:
caused by impaired mitochondrial function leading to metabolic acidosis, rhabdomyolysis, hyperkalemia, hepatomegaly, renal failure, arrhythmia, cardiac failure, and hypertriglyceridemia
True or false. Hypernatremia does not need to be corrected for a brain death exam.
False
What constitutes a positive apnea test for brain death?
PaCO2>60mm Hg or 20mmHg above baseline
Three treatment factors associated with improved mortality for ARDS:
low tidal volume ventilation (6-8cc/kg)
early neuromuscular blockade
prone positioning
True or false. Early enteral nutrition in patients with severe pancreatitis decreases incidence of pancreatic infections and mortality.
True
True or false. For patients with TBI, use of unfractionated heparin for VTE ppx results in lower odds of VTE and lower mortality compared to LMWH
False. LMWH is the preferred management
Common drugs that suppress adrenal function?
ketoconazole and etomidate
Why are high doses of IV lorazepam dangerous?
the diluent includes propylene glycol which can cause lactic acidosis, myocardial depression, and shock
Flexible bronchoscopy causes ____ PaO2 levels and _____ PaCO2 levels in intubated patients.
decreased PaO2
increased PaCO2
In the critical care setting, the target temperature of a patient after cardiac arrest is _____ for 24 hours
33-36C
Two strongest independent risk factors of stress ulcer formation:
respiratory failure requiring mechanical ventilation (strongest factor)
coagulopathy
What alpha 2 agonists can be used as adjuncts to lorazepam in treatment of critically ill patients with alcohol withdrawal for hypertension and tachycardia?
clonidine and dexmedetomidine
Long acting oral agent for alcohol withdrawal:
chlordiazepoxide
Inotrope that is available in premixed bags. Greater effect on cardiac output than NE
dopamine
Pressor that can be given peripherally. Pure adrenergic vasoconstrictor. Can cause reflex bradycardia in spinal cord injury
phenylephrine
Pressor that acts on all 5 adrenergic receptors causing vasoconstriction, vasodilation, inotropy chronotropy, bronchodilation, glycogenolysis, and lipolysis.
epinephrine
Pressor that constricts arterioles via V1a receptor. Second line agent to catecholamine agents in septic shock.
vasopressin
Recommendation for initial crystalloid infusion in sepsis:
30cc/kg within 1st 3 hours
True or false. Hetastarch should be used in sepsis due to decreased risk of AKI & death
False. increased risk of death and AKI
treatment of monomorphic ventricular tachycardia
immediate cardioversion
treatment of monomorphic ventricular ectopy
amiodarone
tx of narrow complex ventricular tachycardia
calcium channel blockade of AV node
tx of bradycardia
atropine
Definition of sepsis:
qSOFA score of at least 2 in the setting of suspected infection
components of qSOFA:
RR>/= 22, altered mental status, SBP = 100
definition of septic shock:
persistent hypotension requiring pressors to maintain MAP>65 and lactate >2 despite adequate resuscitation
Associated factors for patients over the age of 75 with posteroperative delirium:
ASA III-IV
impaired mobility
use of opioids
Nutritional needs for critically ill patients:
25-30 kCal/kg
TBI and intracranial hemorrhage patient chemoprophylaxis:
LMWH within 24-48 hrs
criteria for use of TXA in trauma:
- adult patient in hemorrhagic shock within known predictors of fibrinolysis
- give only if less than 3 hours from injury
- dose 1 g IV over 10 minutes followed by 1 g IV over 8 hours
HDS patients with positive pericardial fast should be managed with:
subxiphoid pericardiotomy
Increasing PEEP will cause what cardiovascular effects?
reduction in cardiac output secondary to decreased venous return and left ventricular stroke volume; elevates intrathoracic pressure and restricts right ventricular heart filling
Goal cerebral perfusion pressure and intracranial pressure for TBI patients:
60-70mm Hg for CPP and <20 for ICP
how is CPP calculated?
MAP-ICP
