This document discusses hemorrhagic shock, which is a condition of reduced tissue perfusion caused by a loss of circulating blood volume from trauma or gastrointestinal bleeding. It outlines the pathophysiology, signs and symptoms, diagnostic evaluation including lab tests and imaging, and management with fluid resuscitation, blood transfusions, controlling the source of bleeding surgically if needed, and treating complications. The key points are that hemorrhagic shock results from acute blood loss, causes decreased cardiac output and blood pressure, and must be promptly diagnosed and treated by replacing fluid volume and identifying and stopping the source of bleeding.

1. HEMORRHAGIC
SHOCK Dr Kaushal Deep Singh
Lecturer, Department of Surgery
UPUMS, Saifai

2. Introduction
■ Definition: Inadequate perfusion of tissue.
■ Types:
1. Cardiogenic Shock
2. Hemorrhagic Shock
3. Distributive Shock
4. Neurogenic Shock
■ Hypotension has been traditionally set, arbitrarily, at
< 90 mm Hg.
■ Eastridge suggested that hypotension be redefined
as < 110 mm Hg.
■ In 2008, Bruns and colleagues confirmed the
concept, showing that a prehospital BP < 110 mm Hg
was associated with a sharp increase in mortality and
that 15% of patients with BP < 110 mm Hg would
eventually die in the hospital.

3. Hemorrhagic Shock : Introduction
■ A condition of reduced tissue perfusion from a loss of circulating blood
volume from clinical etiologies, resulting in the inadequate delivery of
oxygen and nutrients that are necessary for cellular function.
■ Penetrating and blunt trauma, gastrointestinal bleeding, surgical losses.
■ Neural and hormonal compensatory mechanisms.

4. Pathophysiology
acute loss of circulating volume → Corticotropin-releasing hormone is stimulated directly
↓ ↓
decreased cardiac output and decreased pulse pressure Glucocorticoid and beta-endorphin release
↓ Vasopressin increases
baroreceptors in the aortic arch and atrium stimulated Renin leads to increased aldosterone
↓ Glucagon and growth hormone catecholamines
neural reflexes cause an increased sympathetic outflow ↓
↓ Stress response
increase in heart rate, vasoconstriction, and redistribution of blood flow Sodium and water resorption
Hyperglycemia

6. History
■ Type, amount, and duration of bleeding
■ For GI bleeding, knowing if the blood was per rectum or per os is important.
Because it is hard to quantitate lower GI bleeding
■ All episodes of copious bright red blood per rectum should be considered
major bleeding until proven otherwise.
■ Bleeding because of trauma is not always identified easily.
■ Pleural space, abdominal cavity, mediastinum, and retroperitoneum are all
spaces that can hold enough blood to cause death from exsanguination.
■ External bleeding from trauma can be significant and can be underestimated.
■ Scalp lacerations are notorious for causing large underestimated blood loss.
■ Multiple open fractures can lead to the loss of several units of blood.

7. Physical Examination
■ locating the source of bleeding
■ severity of blood loss
■ hypotension, tachycardia, decreased urine output, and altered mental status
■ skin may have a pale, ashen color, usually with diaphoresis
■ patient may appear confused or agitated and may become obtunded.
■ pulse first becomes rapid and then becomes dampened as the pulse pressure
diminishes
■ conjunctivae are inspected for paleness
■ nose and pharynx are inspected for blood
■ chest is auscultated and percussed to evaluate for hemothorax

8. ■ Abdominal examination search for signs of intra-abdominal bleeding,
– distention, pain with palpation, and dullness to percussion
– flanks are inspected for ecchymosis, a sign of retroperitoneal bleeding
– ruptured aortic aneurysms - palpable pulsatile mass in the abdomen
– scrotal enlargement from retroperitoneal blood tracking
– lower extremity mottling
– diminished femoral pulses
– rectum is inspected for blood, identify internal or external hemorrhoids; source of
significant bleeding, most notably in patients with portal hypertension.
■ Patients with a history of vaginal bleeding undergo a full pelvic examination. A
pregnancy test is warranted to rule out ectopic pregnancy.
■ Trauma patients are approached systematically, using the principles of the
primary and secondary examination.

9. Primary Survey
Primary survey is a quick maneuver that attempts to identify life-threatening problems, like
■ To assess the airway, ask the patient's name. If the answer is articulated clearly, the airway is
patent. Cervical spine stabilization. (A)
■ The oral pharynx is inspected for blood or foreign materials. (A)
■ The neck is inspected for hematomas or tracheal deviation. (B)
■ The lungs are auscultated and percussed for signs of pneumothorax or hemothorax. (B)
■ The radial and femoral pulses are palpated for strength and rate. (C)
■ A quick inspection is made to rule out any external sources of bleeding. (C)
■ Gross neurological examination is performed by asking the patient to squeeze each hand and
dorsiflex both feet against pressure. (D)
■ Advanced trauma life support (ATLS) suggests that a "miniature" neurologic examination
categorizes the patient's level of consciousness by whether the patient is alert, responds to voice,
responds to pain, or is unresponsive (ie, AVPU).
■ Patient then is exposed completely, taking care to maintain thermoregulation with blankets and
external warming devices. (E)

10. Secondary Survey
Secondary examination is a head-to-toe, careful examination that attempts to identify all injuries, as
follows:
■ Scalp is inspected for bleeding. Any active bleeding from the scalp should be controlled before
proceeding with the examination.
■ Mouth and pharynx are examined for blood.
■ Abdomen is inspected and palpated. Distention, pain on palpation, and external ecchymosis are
indications of intra-abdominal bleeding.
■ Pelvis is palpated for stability. Crepitus or instability may be an indication of a pelvis fracture,
which can cause life-threatening hemorrhage into the retroperitoneum.
■ Long bone fractures are noted by localized pain to palpation and boney crepitus at the site of
fracture. All long bone fractures should be straightened and splinted to prevent ongoing bleeding
at the sites. Femur fractures are especially prone to large blood losses and should be immobilized
immediately in a traction splint.
■ Further diagnostic tests are warranted to diagnose intrathoracic, intra-abdominal, or
retroperitoneal bleeding.

11. Laboratory Studies
■ Hemogram
– Hemoglobin and hematocrit values remain unchanged from baseline immediately after
acute blood loss.
– Due to fluid resuscitation, the hematocrit may fall.
– A hemoglobin concentration of less than 7 g/dL in the acute setting in a patient that was
otherwise healthy requires transfusion.
■ Arterial blood gas (ABG)
– Acidosis is the best indicator in early shock.
– Blood gas with a pH of 7.30-7.35 is abnormal but tolerable in the acute setting.
– pH below 7.25 may begin to interfere with catecholamine action and cause hypotension
unresponsive to inotropics.
– Life-threatening acidemia (pH < 7.2) initially may be buffered by the administration of
sodium bicarbonate to improve the pH.
■ Coagulation studies generally produce normal results in the majority of patients with severe
hemorrhage early in the course.
■ PT, aPTT, bleeding time, thromboelastography and qualitative platelet dysfunction.

12. ■ Electrolyte studies
– Sodium and chloride may increase significantly with administration of large amounts of
isotonic sodium chloride.
– Hyperchloremia may cause a non–ion gap acidosis and significantly worsen an existing
acidosis.
– Calcium levels may fall with large-volume, rapid blood transfusions.
– Potassium levels may rise with large-volume blood transfusions.

13. Imaging Studies
■ Identifying the source of bleeding.
■ Chest radiographs – Hemothorax
■ Ultrasonography - Focused abdominal sonographic technique (FAST) examination realistically has
replaced diagnostic peritoneal lavage as the test of choice for identifying intraperitoneal fluid in the
trauma patient.
■ CT scan – Investigation of choice for diagnosing and evaluating intrathoracic, intra-abdominal, and
retroperitoneal bleeding.
■ Esophagogastroduodenoscopy -Test of choice for acute upper GI bleeding.
■ Colonoscopy -To diagnose acute lower GI bleeding.
■ Angiography –
– In cases of lowerGI bleeding, angiography is one of the best tests to localize a bleeding source.
– Angiography usually can detect bleeding that is at least 1-2 mL/min.
– Selective angiograms of the celiac, superior mesenteric, and inferior mesenteric arteries are performed
to locate the areas of bleeding.
– Best time to perform the examination is when the patient is actively bleeding.
– Once the source is identified, embolotherapy may be used as an acute means of arresting
hemorrhage.

14. ■ Nuclear medicine scanning -To localizeGI bleeding.
– Tagged red blood cell scan test requires a significant amount of time to complete, but it is
very sensitive, detecting bleeding as slow as 0.5 mL/min.
Procedures
■ Diagnostic peritoneal lavage is a bedside procedure that utilizes a small midline laparotomy
and insertion of a catheter directly into the peritoneal cavity.
– If more than 5 mL of blood is aspirated, the test result is said to be grossly positive and
laparotomy usually is indicated.
– If blood is not aspirated, 1000 mL of warm lactated Ringer’s solution is infused into the
abdomen and then allowed to drain out into the IV bag. The contents of the bag are
examined in the lab.
– A red blood cell count of greater than 10,000 per µL is considered a microscopically positive
test result.
– White blood cell count greater than 500/µL; high levels of amylase, lipase, or bilirubin.
■ Chest tube (Tube thoacostomy) – Hemothorax
– Surgical exploration with open thoracotomy is mandated in the presence of persistent
bleeding; the presence of more than 1500 mL of blood in the initial chest tube drainage; or
drainage of more than 200 mL/h for 2-4 hours.

15. Medical Care
■ Primary treatment of hemorrhagic shock is to control the source of bleeding as soon
as possible and to replace fluid.
■ In controlled hemorrhagic shock (CHS), where the source of bleeding has been
occluded, fluid replacement is aimed toward normalization of hemodynamic
parameters.
■ In uncontrolled hemorrhagic shock (UCHS), in which the bleeding has temporarily
stopped because of hypotension, vasoconstriction, and clot formation, fluid treatment
is aimed at restoration of radial pulse or restoration of sensorium or obtaining a blood
pressure of 80 mm Hg by aliquots of 250 mL of lactated Ringer's solution (hypotensive
resuscitation – permissive hypotension).
■ Immediately administer 2 L of isotonic sodium chloride solution or lactated Ringer’s
solution. Fluid administration should continue until the patient's hemodynamics
become stabilized.
■ Because crystalloids quickly leak from the vascular space, each liter of fluid expands
the blood volume by 20-30%; therefore, 3 L of fluid need to be administered to raise
the intravascular volume by 1 L.

16. ■ Colloids restore volume in a 1:1 ratio.
■ Human albumin, hydroxy-ethyl starch products (mixed in either 0.9% isotonic
sodium chloride solution or lactated Ringer’s solution), or hypertonic saline-
dextran combinations.
■ Hypertonic saline has the theoretical benefit of increasing intravascular volume
with only small amounts of fluid.
■ PRBCs should be transfused if the patient remains unstable after 2000 mL of
crystalloid resuscitation. For acute situations, O-negative noncrossmatched
blood should be administered. Administer 2 U rapidly, and note the response.
For patients with active bleeding, several units of blood may be necessary.
■ Concept of 1:1:1 transfusion
■ Concept of walking blood bank
■ Concept of massive transfusion
■ Role of recombinant factorVIIIa (rFVIIa), tranxemic acid

17. Surgical Care
■ Acute life-threatening bleeding within the abdominal or thoracic cavity is an
indication for operation.
■ Retroperitoneal bleeding is difficult to control operatively and generally is
treated nonoperatively.
■ Severe upper GI bleeds should be managed first by EGD, with the possibility of
cauterizing or injecting the bleeding source with epinephrine. Failure of
endoscopic management usually is an indication for surgery.
■ Confirm the location of a lower GI bleed before operative intervention is
performed.
■ Severe vaginal bleeding should prompt early involvement of the gynecologist.
■ Ectopic pregnancies are treated with immediate surgery.
■ Abruptio placenta is a true emergency and should prompt immediate
cesarean section.

18. Complications
■ Death
■ MODS
■ ARDS