Shock Syndromes II

Answer: D

This patient has class II hemorrhagic shock caused by

penetrating trauma (heart rate greater than 100 beats/

minute, respiratory rate 20–30 breaths/minute, and

anxious on examination). The appropriate resuscitation

strategy should focus on selecting the fluid, volume, and

resuscitation goal. Recommended end points for resus-

citation include SBP greater than 90 mm Hg, urinary

output greater than 30 mL/hour, and normal menta-

tion. Administering fluid to target an SBP greater than

90 mm Hg would be appropriate (Answer A is incor-

rect). Blood products for transfusion are indicated when

the patient’s estimated blood loss is greater than 30%

(Answers B and C are incorrect because the patient has

class II hemorrhagic shock). Given his hemorrhagic

shock class, the patient may be initially managed with

crystalloid boluses targeting a urinary output greater

than 30 mL/hour, an SBP greater than 90 mm Hg, and

normal mentation (Answer D is correct).

Using the Parkland formula for burn resuscitation, the

24-hour fluid requirement would be 13.6 L, to be seg-

mented into the first 8 hours of resuscitation and the

remaining 16 hours. Calculating fluid requirements

according to weight and TBSA to target a urinary out-

put of greater than 0.5 mL/kg/hour would be correct

(Answers A, C, and D are incorrect). Answer B is cor-

rect because the total volume requirement accounting

for prehospital fluid, titration of fluid rates, and target

urinary output are appropriate.

Answer: D

Given this patient’s hemodynamic parameters in a posi-

tive FAST examination, he will likely require a massive

transfusion, as assessed by the ABC (Assessments of

Blood Consumption) score for an MTP, which should be

initiated promptly. A fixed ratio of 1:1:1 PRBC, plasma,

and platelets is more likely to achieve hemostasis and

lower mortality from exsanguination at 24 hours than is

2:1:1 (Answer D is correct). Although fluid resuscitation

is an adjunct to increase intravascular volume and tis-

sue perfusion, 0.9% sodium chloride does not increase

oxygen-carrying capacity, and total volume should

be minimized to less than 1.5 L (Answer A is incor-

rect). In a traumatic hemorrhage, a normal hemoglobin

likely will not reflect the extent of blood loss secondary

to hemoconcentration until capillary recruitment is

complete or resuscitation begins. In addition, resusci-

tation efforts in a hemodynamically unstable patients

should not be delayed while awaiting laboratory results

(Answer B is incorrect). Although vasopressors may

be considered an adjunct to maintain tissue perfusion

while minimizing fluid volume, this strategy should be

reserved for those with life-threatening hypotension

despite resuscitation efforts (Answer C is incorrect).

Answer: B

Acute hypocalcaemia is a common complication in a

massive transfusion secondary to citrate added to stored

blood. Calcium is essential for stabilization of fibrin,

and low ionized calcium concentrations in traumatic

hemorrhage are associated with increased mortality.

Therefore, ionized calcium concentrations should be

maintained within the normal range (Answer B is cor-

rect). Evidence is insufficient to recommend sodium

bicarbonate therapy in patients with acute trauma and

has the potential for increased mortality. The patient’s

acidosis should be corrected by addressing the under-

lying cause – in this case, hemorrhage (Answer A is

incorrect). Use of rFVIIa should only be considered

if major bleeding and persistent traumatic coagulopa-

thy persist despite best practice, inconsistent with the

patient’s current condition. In addition, a pH less than

7.2 is a predictor of a poor response to rFVIIa (Answer

C is incorrect). Unfortunately, this patient’s injury was 5

hours ago, and he has no laboratory evidence of hyper-

fibrinolysis. In this setting, tranexamic acid does not

improve mortality after 3 hours from injury and has

been associated with an increased risk of death from

bleeding (Answer D is incorrect).

Answer: C

At this point, ongoing resuscitation should be goal

directed. The TEG reveals hypofibrinolysis or “shut-

down,” not hyperfibrinolysis for which tranexamic

acid is expected to help. In addition, if there was no

TEG to evaluate for hypofibrinolysis, tranexamic acid

should be administered within the first 3 hours from

injury, and this patient’s injuries occurred more than

4 hours earlier (Answers B and D are incorrect). With

the updated history that the patient was taking dabi-

gatran preinjury, dabigatran is likely contributing to

the patient’s ongoing coagulopathy and hemorrhage.