A 28-year-old woman with a stab wound to the left flank and signs of Class III hemorrhagic shock (systolic BP 90 mmHg, HR 130/min, altered mental status) is being resuscitated in the trauma bay. Regarding fluid resuscitation and blood product management in hemorrhagic shock, all of the following are appropriate EXCEPT:

Explanation

## Fluid Resuscitation and Transfusion in Hemorrhagic Shock ### Modern Approach: Damage Control Resuscitation **Key Point:** The paradigm has shifted from aggressive crystalloid resuscitation to **balanced resuscitation** with early blood products and permissive hypotension in uncontrolled hemorrhage. ### Crystalloid Selection: Saline vs. Balanced Solutions | Fluid | Composition | Advantage | Disadvantage | | --- | --- | --- | --- | | **Normal Saline (0.9% NaCl)** | Na^+^ 154, Cl^−^ 154 mEq/L | Cheap, widely available | **Hyperchloremic acidosis**, volume overload | | **Lactated Ringer's (LR)** | Na^+^ 130, K^+^ 4, Cl^−^ 109, Lactate 28 mEq/L | Balanced electrolytes, less acidosis | Slightly more expensive | | **Plasma-Lyte** | Physiologic electrolytes | Balanced, no hyperchloremia | Most expensive | **High-Yield:** While normal saline is cheaper and more available, **lactated Ringer's is now preferred** in trauma resuscitation because it avoids the hyperchloremic metabolic acidosis associated with large-volume normal saline infusion. This is especially important in prolonged resuscitation. ### Principles of Hemorrhagic Shock Management ```mermaid flowchart TD A[Hemorrhagic Shock Suspected]:::outcome --> B{Uncontrolled Hemorrhage?}:::decision B -->|Yes| C[Permissive Hypotension<br/>SBP 80-90 mmHg]:::action B -->|No| D[Target SBP > 90 mmHg]:::action C --> E[Activate Massive Transfusion Protocol]:::action E --> F[Balanced Transfusion<br/>1:1:1 PRBC:FFP:Plt]:::action D --> G[Crystalloid bolus<br/>LR preferred over NS]:::action F --> H[Damage Control Surgery]:::action G --> I{Shock Reversal?}:::decision I -->|No| E I -->|Yes| J[Continue resuscitation<br/>Monitor for complications]:::action ``` ### Why Normal Saline Is NOT the Preferred Choice **Clinical Pearl:** The "normal" in normal saline is a misnomer. Its chloride concentration (154 mEq/L) is much higher than plasma (98–107 mEq/L). Large-volume infusion causes: - **Hyperchloremic metabolic acidosis** (worsens tissue perfusion) - **Acute kidney injury** (chloride-induced renal vasoconstriction) - **Increased mortality** in critically ill patients (recent meta-analyses) **Warning:** Do not confuse "most available" with "most appropriate." NEET PG and ATLS emphasize evidence-based choice, not convenience. ### Balanced Transfusion (1:1:1 Ratio) **Key Point:** In massive transfusion, a 1:1:1 ratio of packed RBCs : fresh frozen plasma : platelets reduces: - Coagulopathy - Mortality (compared to traditional 8:1 or 5:1 ratios) - Complications from crystalloid overload ### Permissive Hypotension **High-Yield:** In **uncontrolled hemorrhage** (before surgical hemostasis), permissive hypotension (target SBP 80–90 mmHg) is maintained to: - Reduce ongoing blood loss - Avoid dislodging clots - Minimize crystalloid-induced edema Once hemorrhage is controlled, resuscitation targets SBP > 90 mmHg.