Resuscitation in Surgery

1. Pathophysiology of Surgical Shock

• Fischer's Mastery of Surgery, 8e, p. 7368
• Sabiston Textbook of Surgery, p. 585

2. Historical Evolution of Resuscitation

• Korean War era: Limited salt/water was given; blood and blood products were found beneficial.
• Vietnam War era: Volume resuscitation with lactated Ringer's (LR) became standard after Shires' landmark dog studies, which showed LR + blood improved survival vs. blood alone. Surgeons pushed toward aggressive crystalloid use.
• The problem: What emerged was "Da Nang lung" (ARDS), initially attributed to better survival from aggressive resuscitation. However, killed-in-action rates had not changed. The real culprit was likely the LR solution itself triggering neutrophil activation and the inflammatory cascade.
• Modern recognition: US Navy experiments showed neutrophil activation occurred equally in controls receiving LR without hemorrhagic shock - implicating the fluid, not the shock, as the driver of inflammation. This prompted the shift to DCR.
• Sabiston Textbook of Surgery, pp. 580-584

3. Phases of Resuscitation in Trauma Surgery

Phase 1 - Uncontrolled Hemorrhage (OR/Acute)

• Permissive hypotension (target MAP ~50-65 mmHg)
• Empiric hemostatic resuscitation (blood products, not crystalloids)
• Minimize time to surgical hemorrhage control

• Increased blood pressure disrupts forming clots and increases rebleeding
• Decreased blood viscosity and hematocrit
• Decreased clotting factor concentration
• Greater transfusion requirement
• Hypothermia
• Premature reperfusion injury
• Direct immune suppression

Phase 2 - ICU Stabilization

Phase 3 - Definitive Management

• Miller's Anesthesia, 10e, p. 9401-9403

4. Damage Control Resuscitation (DCR)

BOX - Components of DCR (Sabiston Box 33.2)

1. Permissive hypotension until definitive surgical hemorrhage control
2. Minimize crystalloid use
3. Initial use of 5% hypertonic saline (where available)
4. Early blood products - PRBCs, FFP, platelets, cryoprecipitates
5. Consider drugs to treat coagulopathy: rFVIIa, prothrombin complex concentrate (PCC), tranexamic acid (TXA)

Evidence for DCR:

• Aggressive early use of PRBCs + FFP reduced total PRBC use by 25%
• DCR reduced incidence of ARDS, MODS, extremity and abdominal compartment syndromes, and mortality
• ARDS now occurs mainly from pulmonary contusion, long bone fractures, pneumonia, or sepsis - no longer a common complication in patients receiving DCR
• Sabiston Textbook of Surgery, pp. 585-586

Permissive Hypotension

• Least blood loss occurs in hypotensive animals, more in controls, and most in animals that underwent vigorous reinfusion during hemorrhage
• Rebleeding correlates with higher MAP; survival was best in groups resuscitated to lower-than-normal MAP
• Animal studies suggest a target MAP of 60 mmHg based on favorable inflammatory profiles and survival
• Hypotensive resuscitation avoids excessive fluid until surgical hemorrhage control is achieved
• Miller's Anesthesia, 10e, p. 9403

5. Blood Product Resuscitation

Transfusion Ratios

• Packed red blood cells (PRBCs)
• Fresh frozen plasma (FFP)
• Platelets

Resuscitation Fluid Hierarchy (US Military / TCCC)

1. Low-titer type O liquid cold-stored whole blood (FDA-approved, preferred)
2. Fresh whole blood
3. Plasma + PRBCs + Platelets in 1:1:1 ratio
4. Plasma + PRBCs in 1:1 ratio
5. Plasma or PRBCs alone

• Most combat casualties do not require fluid resuscitation
• Oral hydration is underused
• Aggressive crystalloid resuscitation has not been shown beneficial in penetrating trauma
• Resuscitation should be with whole blood or blood components preferentially
• Sabiston Textbook of Surgery, pp. 585-586

Whole Blood Resuscitation

6. Resuscitation Fluids - Current Status

Crystalloids

Colloids

• Schwartz's Principles of Surgery, 11e, pp. 162-175

7. Damage Control Surgery (DCS)

Three Phases of DCS (Fischer's, p. 7367):

Indications for DCS (Table 274.1, Fischer's):

• Difficult-to-access major vascular injury (intrahepatic, retrohepatic, retroperitoneal, pelvic)
• Major liver or combined pancreaticoduodenal injury with hemodynamic instability
• Inability to control bleeding by conventional methods
• Large volume of PRBCs (>10 units) or combined blood products + crystalloids (>12 L) administered pre/intraoperatively
• Hypothermia < 34°C, acidosis, and/or coagulopathy
• Persistent intraoperative cellular shock (lactate >5 mmol/L, pH <7.2, base deficit >15 mmol/L, core temp <34°C, O2 consumption index <100 mL/min/m²)
• Intraoperative ventricular arrhythmias
• Need for staged abdominal wall reconstruction

Intraoperative Warning Signs of Physiologic Derangement:

• Bowel mucosa edema
• Dusky serosa
• Tissues that feel cold to the touch
• Significant abdominal wall edema
• Diffuse oozing from surgical incisions and surrounding tissues
• Fischer's Mastery of Surgery, 8e, pp. 7367-7370

8. Acid-Base Considerations in Surgical Resuscitation

• Results from anaerobic metabolism during hypoperfusion (lactic acidosis)
• Worsened by hyperchloremia from large-volume saline infusion
• Body compensates via Kussmaul respirations (increased ventilation), bicarbonate buffers, and renal bicarbonate generation

Predicted Compensatory Changes (Schwartz's):

Causes of Respiratory Acidosis in Surgical Patients (Schwartz's):

• Narcotics, CNS injury
• Pulmonary: secretions, atelectasis, mucus plug, pneumonia, pleural effusion
• Pain from abdominal/thoracic incisions
• Abdominal distension, compartment syndrome, ascites

Paradoxical Aciduria

• Schwartz's Principles of Surgery, 11e, pp. 119-160

9. Endpoints of Resuscitation

10. Special Considerations

Tranexamic Acid (TXA)

Abdominal Compartment Syndrome (ACS)

MODS (Multi-Organ Dysfunction Syndrome)

Summary