S3C25 - Approach to the patient in shock Flashcards
1
Q
Shock Defn
A
- circulatory insufficiency that creates an imbalance b/w oxygen supply and oxygen demand
- normal lactate level 0.5-1.5mmol/L (increased lactate occurs when anaerobic metabolism is used due to lack of oxygen supply)
- elevated lactate is a marker of impaired O2 delivery and correlates with short-term prognosis of critically ill pts
- physiologic changes in shock:
- arteriolar vasoconstriction
- increase HR, contractility and CO
- venous constriction
- release of epi, NE, dopamine, cortisol (increase vascular tone)
- release of ADH to increase intravasc. volume
- cellular response to shock: hemoconcn, hyperkalemia, hyponatremia, pre-renal azotemia, hyper/hypoglycemia, lactic acidosis
- early stages of shcok = SIRS
2
Q
Shock progression
A
- SIRS to shock and as shock progresses multi-organ dysfxn starts to occur:
- myocardial depression, ARDS, DIC, heaptic failure, renal failure
3
Q
SIRS
A
-2 or more of:
- temp >38 (100.4) or <36
- HR >90
- RR >20
- WBC >12 or <4 or >10% immature bands
4
Q
Shock: BP
A
-usually assoc with BP <90 mmHg but doesn’t have to be
5
Q
Shock: diagnosis
A
- Clinical criteria:
- associated with a decreased venous oxygen content and metabolic acidosis (lactic acidosis)
- 4 types of shock:
- hypovolemic
- cardiogenic
- obstructive
- distributive
6
Q
Shock: hemodynamic monitoring
A
- pulse ox
- ECG
- continuous intra-arterial BP monitoring, ET CO2
7
Q
Shock: investigations
A
Basic:
-CBC, lytes, glucose, Ca, Mg, PO3, BUN, Cr, PT, PTT, INR, u/a, CXR, ECG
Physiologic assessment:
-ABG, lactate, d-dimer/fibrinogen/fibring split products, liver fxn panel
Noninvasive hemodynamic assessment:
-ET CO2, echo
Invasive hemodynamic assessment:
-CO, CVP, ScvO2
Consider:
- blood, sputum, urine, pelvic cultures
- CT head/sinuses
- LP
- wound Cx
- cortisol level
- preg test
- AXR, abdo/pelvic u/s, abdo/pelvic CT
8
Q
Shock management:
A
Airway:
- -intubation results in hypotension from the induction agents and from the decreased preload/CO of PPV, consider fluid resusc first
Breathing:
- -intubating and ventilating decreases WOB, improves oxygenation and decreases hypercapnia
- -goal for >93% O2 sat and PaCO2 of 35-40
- -using hyperventilation to normalize the ph >7.2 is not beneficial
Circulation:
- rapid boluses NS, r/a after each bolus
- vasopressors if inadequate response to fluids
- goal MAP >60 and systolic >90
Adequate Oxygenation:
- sats >93%
- Hb >100, consider PRBC TFN to maintain this
Goals:
- u/o >0.5cc/kg/h
- CVP 8-12mmHg
- MAP 65-90mm Hg
- ScvO2 >70%
9
Q
Shock: Questions to ask if shock persists
A
Equipment and Monitoring:
- is pt appropriately monitored?
- is use of vasopressors masking persisten hypovolemia?
- eqpt malfxn? IV tubing correct? pumps working?
- are vasopressors mixed adequately and in the correct dose?
Pt assessment:
- does mentation and appearance match degree of hypotension?
- is there adequate volume resusc?
- is tehre a pneumo after central line placed?
- is there an occult injury (bullet/stab wound)?
- bleeding from spleen, aneurysm, ectopic preg?
- is there adrenal insufficiency?
- pt having allergy to meds?
- is there cardiac tamponade in the dialysis or cancer pt?
- is there assoc MI, Ao dissection, PE?
10
Q
Fluids
A
Crystalloids = LR, NS
Colloids = Albumin, dextran, gelatin
