Pharmacotherapy Case 17: Hypovolemic Shock Management By: Dr. Nehad Ahmed

 

Chief Complaint:

A 45-year-old male presents to the emergency department with severe weakness, dizziness, and confusion after a reported episode of gastrointestinal bleeding. He is concerned about his rapidly worsening condition and feels very lightheaded when attempting to stand.

Subjective Data:

History of Present Illness (HPI):
The patient is a 45-year-old male who has been experiencing vomiting and diarrhea for the past three days, accompanied by bright red blood in his stool. He also notes that he has had significant abdominal pain. His symptoms have progressively worsened, with increased weakness, dizziness, and confusion. The patient reports feeling very lightheaded upon standing and admits to decreased urine output over the last 24 hours. He denies any recent trauma or injury.

Past Medical History (PMH):

Gastroesophageal reflux disease (GERD), diagnosed 10 years ago

Hypertension, diagnosed 8 years ago

Peptic ulcer disease, diagnosed 5 years ago

No known history of chronic bleeding disorders.

Medications:

Omeprazole 20 mg daily (for GERD)

Lisinopril 10 mg daily (for hypertension)

Amlodipine 5 mg daily (for blood pressure control)

No over-the-counter medications or supplements.

Allergies:

No known drug allergies (NKDA).

Family History:

Father had a history of hypertension and died of stroke at age 68.

Mother has a history of diabetes and chronic kidney disease.

Social History:

Smoking: Occasional smoker, about 5-7 cigarettes per day for the past 10 years.

Alcohol: Drinks socially, approximately 2-3 beers on weekends.

Physical activity: Sedentary lifestyle.

Diet: Consumes a high-fat diet with occasional fast food and little fruit or vegetable intake.

Lives with spouse and two children.

Review of Systems:

Cardiovascular: Occasional palpitations, no chest pain or shortness of breath.

Gastrointestinal: History of vomiting, diarrhea, and bright red blood in stool. No constipation or recent changes in bowel habits.

Neurological: Reports dizziness, confusion, and weakness. No recent headaches, syncope, or focal neurological deficits.

Renal: Decreased urine output, no dysuria or hematuria.

Musculoskeletal: No joint pain, no edema.

Objective Data:

Vital Signs upon Arrival:

Blood Pressure: 80/50 mmHg (low, indicative of shock)

Heart Rate: 120 bpm (tachycardia, compensatory response to low blood volume)

Respiratory Rate: 22 breaths/min (slightly elevated)

Temperature: 36.5°C (97.7°F)

Oxygen Saturation: 98% on room air

Weight: 85 kg (BMI: 28 kg/m²)

Height: 175 cm

Physical Exam:

General: Pale, diaphoretic, and visibly weak. Appears lethargic but alert when addressed.

Cardiovascular: Tachycardic with a rapid, weak pulse. No jugular venous distension. Reduced peripheral pulses, particularly in the lower extremities.

Respiratory: Clear lung fields bilaterally, no wheezing, crackles, or signs of respiratory distress.

Gastrointestinal: Abdomen is distended and tender to palpation in the epigastric region. Bowel sounds are present but reduced.

Neurological: Alert but confused; unable to maintain full attention. No focal deficits.

Renal: Decreased urine output, dark-colored urine noted.

Skin: Cold, clammy skin with delayed capillary refill (>2 seconds).

 

Laboratory Results:

Complete Blood Count (CBC):

Hemoglobin: 7.5 g/dL (low, indicating anemia likely due to bleeding)

Hematocrit: 22% (low, consistent with significant blood loss)

White Blood Cell Count: 8,000/μL (normal)

Platelets: 150,000/μL (normal)

Electrolytes:

Sodium: 138 mEq/L (normal)

Potassium: 4.2 mEq/L (normal)

Bicarbonate: 18 mEq/L (low, indicating metabolic acidosis due to shock)

Creatinine: 1.5 mg/dL (mild elevation, indicating possible renal hypoperfusion)

Blood Urea Nitrogen (BUN): 22 mg/dL (elevated, suggesting dehydration)

Liver Function Tests:

Normal liver enzymes (ALT, AST, ALP)

Coagulation Studies:

Prothrombin Time (PT): 13.2 seconds (normal)

International Normalized Ratio (INR): 1.0 (normal)

Activated Partial Thromboplastin Time (aPTT): 30 seconds (normal)

 

Imaging:

Abdominal Ultrasound: No free fluid in the abdomen, but evidence of gastric ulcer with potential active bleeding.

Chest X-ray: Clear, no signs of fluid overload or pneumonia.

Assessment:

The patient is a 45-year-old male presenting with symptoms of hypovolemic shock, likely due to gastrointestinal bleeding secondary to a gastric ulcer. His symptoms of dizziness, confusion, and weakness, along with vital signs showing hypotension and tachycardia, are consistent with hypovolemic shock. Laboratory findings indicate significant anemia (low hemoglobin and hematocrit), likely resulting from the ongoing bleeding, and renal impairment (elevated BUN and creatinine), consistent with renal hypoperfusion.

The patient's gastric ulcer and the associated gastrointestinal bleeding are the most likely cause of his hypovolemia. He requires immediate volume resuscitation, correction of his electrolyte imbalance, and treatment of the underlying bleeding.

Plan:

Initial Management:

Fluid Resuscitation:

Begin IV normal saline (0.9% sodium chloride) at 1-2 liters within the first hour. Monitor vital signs and urine output closely. Consider lactated Ringer’s solution if there is no improvement in perfusion.
Administer blood products (packed red blood cells) as needed to maintain hemoglobin levels above 7 g/dL.

Oxygen Therapy:
Provide supplemental oxygen to maintain SpO2 above 92%.

Monitor Hemodynamics:
Continuous monitoring of blood pressure, heart rate, urine output, and oxygen saturation.
Consider using central venous pressure (CVP) or arterial line for closer monitoring of hemodynamics if the patient’s condition remains unstable.

Pharmacotherapy:

Proton Pump Inhibitor (PPI):
Initiate IV pantoprazole 80 mg bolus followed by 8 mg/hour infusion for acid suppression to reduce gastric acid secretion and promote ulcer healing.

Antibiotics:
If the patient is at risk for infection or if there is suspicion of a Helicobacter pylori infection, initiate clarithromycin, amoxicillin, and esomeprazole (triple therapy).

Vasopressors:
If hypotension persists despite adequate fluid resuscitation, initiate norepinephrine (starting at 0.01-0.05 mcg/kg/min) for hemodynamic support.

Endoscopic Evaluation:

Refer the patient for an urgent upper gastrointestinal endoscopy to assess the source of bleeding, identify the ulcer, and consider therapeutic interventions (e.g., endoscopic cauterization or clipping).

Renal Monitoring:

Monitor renal function closely (serum creatinine, BUN) and urine output. Initiate renal protective measures, including adequate hydration and avoidance of nephrotoxic agents.

Blood Transfusion:

Crossmatch and provide packed red blood cells if hemoglobin levels drop below 7 g/dL or if there are signs of inadequate tissue perfusion despite fluid resuscitation.

Monitoring and Follow-Up:

Frequent reassessments of vital signs, laboratory values, and urine output.

Daily monitoring of CBC, renal function, and electrolytes.

Follow-up imaging (abdominal ultrasound or CT) to evaluate for complications, such as perforation or continued bleeding.

Patient Education:

Once stable, educate the patient about the importance of gastric ulcer management, including lifestyle changes (e.g., avoiding NSAIDs, alcohol, and smoking), and following up for further evaluation of H. pylori if needed.

Discussion:

Hypovolemic shock is a life-threatening condition that requires rapid recognition and intervention. This patient’s hypovolemic shock is likely due to gastrointestinal bleeding from a gastric ulcer, and timely volume resuscitation, as well as proton pump inhibitor therapy, is essential. Close monitoring of vital signs, renal function, and laboratory values is required to guide further therapy and prevent complications. Endoscopy plays a crucial role in both diagnosis and management of the bleeding ulcer. Managing hypovolemic shock involves a multidisciplinary approach, including pharmacotherapy, volume replacement, and possible surgical or endoscopic intervention.