What is the management of hypovolemic shock?

Management of Hypovolemic Shock

The management of hypovolemic shock requires immediate fluid resuscitation with crystalloids or colloids, rapid identification and control of bleeding sources, and hemodynamic support with vasopressors if needed after adequate volume replacement. 1, 2

Initial Assessment and Diagnosis

• Evaluate the extent of hypovolemic shock using a combination of patient physiology, anatomical injury pattern, mechanism of injury, and response to initial resuscitation 2
• Use the shock index (heart rate/systolic blood pressure) and/or narrow pulse pressure to assess the severity of hypovolemic shock and transfusion requirements 1
• Look for clinical signs of hypoperfusion: tachycardia, hypotension, cold extremities, increased capillary refill time (>2 seconds), decreased urine output (<1 ml/kg/hour), confusion, and decreasing level of consciousness 2, 3
• Measure blood lactate levels to estimate and monitor the extent of bleeding and tissue hypoperfusion; base deficit may be used as an alternative if lactate is unavailable 2, 3

Immediate Intervention

• Patients with an obvious bleeding source or in hemorrhagic shock in extremis should undergo immediate bleeding control procedures 2
• Establish large-bore intravenous access (preferably two lines) as quickly as possible 2, 1
• Collect blood for laboratory tests including complete blood count, coagulation profile, and cross-matching 2
• Avoid hyperventilation in severely hypovolemic patients as it may decrease cardiac output 2

Fluid Resuscitation

• Begin with crystalloid isotonic solutions (balanced crystalloids or 0.9% saline) or albumin with initial boluses of 20 ml/kg for crystalloids administered over 5-10 minutes 1, 3
• Titrate fluid administration according to clinical response: normalization of heart rate, blood pressure, capillary refill time, mental status, and urine output 1, 3
• In adults with signs of shock, administer boluses of 500-1000 ml of crystalloids in 30 minutes 3
• For children in hypovolemic shock, use boluses of 20 ml/kg of colloid or 0.9% saline; consider 20 ml/kg of 4.5% albumin if the child is in coma 2
• Monitor for signs of fluid overload: hepatomegaly, pulmonary rales, increased jugular venous pressure 2, 3
• Apply the fluid challenge technique where fluid administration continues while hemodynamic parameters improve 1

Vasopressor Support

• If hypotension persists despite adequate fluid resuscitation, initiate vasopressor therapy 1, 3
• Norepinephrine is the first-choice vasopressor to achieve a target mean arterial pressure (MAP) of 65 mmHg 1, 4
• Administer norepinephrine in 5% dextrose solution (dilute 4 mg in 1000 ml) via a central venous catheter whenever possible 4
• Start with 2-3 ml/minute (8-12 mcg/minute) and adjust according to blood pressure response; average maintenance dose ranges from 0.5-1 ml/minute (2-4 mcg/minute) 4
• Monitor blood pressure every 2 minutes until target is reached, then every 5 minutes if administration continues 4

Blood Product Administration

• Maintain hemoglobin at a minimum of 10 g/dL in patients with ongoing hemorrhage 2
• For severe hemorrhagic shock, implement a balanced transfusion strategy with a ratio of red blood cells, plasma, and platelets of 4:4:1 5
• Consider early administration of tranexamic acid and fibrinogen to stabilize coagulation in hemorrhagic shock 5

Ongoing Monitoring and Management

• Continuously monitor vital signs, urine output, mental status, and peripheral perfusion 2, 1
• Perform repeated hemoglobin/hematocrit measurements to detect ongoing bleeding 2
• Consider central venous pressure monitoring in complex cases to guide fluid management 2
• Maintain normothermia, pH above 7.2, and normal calcium levels 5
• In cases of severe shock not responding to 40 ml/kg of fluid resuscitation, consider rapid sequence intubation and mechanical ventilation 2

Special Considerations

• In patients with traumatic brain injury or altered consciousness, be cautious with volume resuscitation to avoid increasing intracranial pressure 2
• For elderly patients or those with obliterative vascular disease, avoid administering vasopressors into leg veins due to increased risk of ischemic complications 4
• Consider permissive hypotension in hemorrhagic shock until definitive bleeding control is achieved, except in traumatic brain injury 5
• Avoid etomidate for intubation in septic shock due to its inhibitory effects on adrenal corticosteroid biosynthesis 2

Common Pitfalls to Avoid

• Delaying control of obvious bleeding sources while waiting for diagnostic confirmation 2
• Excessive fluid administration without evaluating response, which can lead to volume overload and pulmonary edema 3
• Using vasopressors before adequate volume resuscitation 4
• Failing to monitor for extravasation when administering vasopressors, which can cause local tissue necrosis 4
• Relying solely on blood pressure as an indicator of shock resolution rather than using multiple perfusion parameters 1, 3