Anesthesia Flashcards
fluid therapy in hypovolemic shock
20 cc/kg Bolus
or
2 Liter NS / RL
can be repeated
blood transfusion is initiated
after 2nd bolus
serum lactate of …… indicates severe hypoxia and poor prognosis
> 4 mmol/L
M/C type of shock in adults
Distributive (septic)
↓
VD → ↓ SVR → > 65 % of blood pools in venous system
M/C cause of anaphylactoid shock
X-Ray contrast media
1st exposure
Anaphylactoid shock is mediated by
Basophils and Mast cells
regarding anaphylactic/anaphylactoid
- may manifest after 12h of initial event
- Thromboembolic events are seen as often as arrhythmias and ventricular dysfunction
how differentiate clinically between neurogenic shock and other types of shock
Bradycardia (others is tachy)
SAP < 100mmHg
HR < 60/min
hypoperfusion + normal intravascular volume
Cardiogenic shock
diagnosed by echo
regarding caval compression syndrome
changing the position of the patient may be enough ( left lateral position)
how to differentiate between Cardiogenic and hypovolemic shock
assessment of intravascular volume
early indicator of shock
lactic acidosis
first sign of decompensated shock
brief, self limiting episodes of hypotension
M/C type of shock in pediatrics
hypovolemic
shock index
> 0.9
shock index = HR/SBP , Normal = 0.5 ~ 0.7
regarding NIRS
- early warning of shock progression during acute hemorrhage
- monitor microvasculature status in septic shock
- less useful during prolonged shock state
subcostal view in GDE
Assessment of IVC (cyclic variation with respiration on cases of hypovolemia)
in hypothermia, when does shivering decrease
32 ~ 30c
regarding subacute hypothermia
- Develops over hours/ days
- Accompanied by hypovolemia
- Treatment requires fluids + re warming
in heat exhaustion, all vitals are affected except
blood pressure
- skin is normal ro cool
regarding superficial frostbite
skin feels warm
to differentiate between heat exhaustion and heat stroke
- Intact mental function
- Core temperature < 39
treatment of heat exhaustion
- Adults → 200 ml increments
- peds → 20 ml/kg , repeated to max. 60 ml/kg
effect of salt water drowning
hypovolemia & hemoconcentration
freshwater is the opposite effect
goal of heat stroke treatment is to
decrease temperature to < 39 c within 30 minutes
factors affecting survival of drowning
- Types of water:
- Cleanliness of the water.
- Length of time submerged
- Age and health of victim
- Temperature of water (cold water = under 68 degrees.)
criteria of major burn
1- Affect more than 15%-20% burns in an adult and more than 10% burns in a child.
2- Third degree burn.
3- Burns of special regions: face, hands, feet, perineum .
4- Circumferential burns.
5- Inhalation injury.
6- burn + major trauma
time of appearance of inhalational injury
2 ~ 48 hours after the burn
Management of combustion compound intoxication
empiric 100% high flow O2 for 4 ~ 6 hours via non-breathing mask
pulse oximetry cannot be relied on as it doesn’t distinguish between OxyHb and CarboxyHb
fluid equation in burn
2ml Rl x BW (kg) x %TBSA
1/2 fluids given in first 8 hours
other 1/2 in the subsequent 16h
choice of IV fluids depends on
the cause of deficit
regarding colloids
- hydroxyethyl starch increases risk of renal injury
- albumin has been associated with poorer outcomes in patients with traumatic brain injury
- dextrans and hydroxyethyl starch may adversely affect coagulation when > 1.5 L is
given
main CCC of normal saline
hyperchloremic metabolic acidosis
regarding fluids resucitation
amount of IV fluids is more important than the type
Ringer lactate vs Normal saline
- RL is closer to physiological pH
- RL is not ideal for transfusion patients
- RL should not be used where plasma osmolality is important – ie acute
brain injury. - Neither is superior to the other
contraindications of ringer’s lactate
- Liver failure (Impaired lactate metabolism) ⚠️
- Severe hyperkalemia (Contains potassium) 🚫
- Neurological conditions
contraindications of normal saline
- Metabolic acidosis (Can worsen acidosis) ❌
- Hypernatremia & CHF (Can contribute to sodium overload)
IV fluids in trauma
give 1 liter of IV fluid,
and if no normalization of BP,
give blood products.
best indicator of end-organ perfuison
urine output of > 0.5 to 1 mL/kg/hour
US use in volume depletion
respiratory collapse of the inferior
vena cava greater than 50%
Normal CVP values
2 to 7 mm Hg (3 to 9 cm water)
When the CVP is within the normal range, volume depletion cannot be excluded
measure response to 100 ~ 200 ml bolus
End goals of fluid resucitation
- MAP ≥ 65 mmHg
- HR < 100/min
- Urine output Adults ≥ 0.5 ml/kg/h
(Pediatrics ≥ 1 ml/kg/h) - ScvO 2 ≥ 70%
- Serum lactate ≤ 2 mmol/l
Isotonic solutions provide better intravascular filling,
with 25% to 30% of crystalloid infusion remaining in
the circulation for
1 ~ 2 hours