Intra-abdominal Hypertension - Wendy R. Greene, MD

Summary

In this presentation, Dr. Linda Green discusses intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) through case studies. She explains how elevated intra-abdominal pressure can affect multiple organs, leading to severe complications such as renal failure, hypoxemia, and multi-system organ failure. Dr. Green highlights the importance of accurate pressure measurement, early intervention, and management options like paracentesis, decompression, and surgical procedures. She stresses that ACS can develop in any patient and emphasizes the need for prompt monitoring to prevent life-threatening outcomes.

Takeaways

• 🤔 Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are critical issues that can develop in various patients, not just trauma cases.
• 👩‍⚕️ A 67-year-old female with liver disease experienced worsening conditions, including difficulty with ventilation, hypoxemia, and hypotension. Intra-abdominal pressure measured at 45 mmHg, leading to a diagnosis requiring paracentesis.
• 💡 Paracentesis was performed, removing 4500cc of fluid, which reduced intra-abdominal pressure and resolved the patient's pulmonary, renal, and hemodynamic issues.
• 👨‍⚕️ A 37-year-old male developed an ileus with massive bowel distention but no free fluid. Intra-abdominal pressure was 31 mmHg, and an NG tube decompression was used to relieve the pressure.
• 📏 Intra-abdominal pressure is measured using a Foley catheter, ensuring the patient is supine, and the transducer is zeroed appropriately. Normal pressure is between 5-10 mmHg.
• ⚠️ Abdominal compartment syndrome (ACS) occurs when intra-abdominal pressure exceeds 20 mmHg, causing organ dysfunction and decreased abdominal perfusion pressure.
• 🧠 ACS impacts multiple organs, causing decreased cardiac output, hypoxemia, renal dysfunction, and elevated intracranial pressure due to reduced blood flow.
• 🔄 Primary ACS is caused by intra-abdominal processes, while secondary ACS arises from factors like aggressive resuscitation.
• 🩺 Treatment includes neuromuscular blockade, ventilator support, decompressive surgery, and supportive management. Surgical decompression may involve temporary wound closures.
• 🚨 Early detection of intra-abdominal hypertension is crucial, as delayed intervention can turn urgent problems into emergencies, resulting in multi-organ failure.

Q & A

What is intra-abdominal hypertension (IAH) and how is it measured?

Intra-abdominal hypertension (IAH) is an elevated pressure within the abdominal cavity, typically measured using a Foley catheter with sterile saline infusion. The patient should be supine, relaxed, and the transducer zeroed appropriately. Normal intra-abdominal pressure is between 5-10 mmHg.

What are the stages of intra-abdominal hypertension?

Intra-abdominal hypertension is classified into four grades based on severity: Grade 1 (12-15 mmHg), Grade 2 (16-20 mmHg), Grade 3 (21-25 mmHg), and Grade 4 (greater than 25 mmHg).

What is abdominal compartment syndrome (ACS) and how does it develop?

Abdominal compartment syndrome (ACS) occurs when intra-abdominal pressure exceeds 20 mmHg, leading to organ dysfunction. It can result from primary intra-abdominal issues or secondary causes like aggressive fluid resuscitation.

How does intra-abdominal hypertension affect the body systems?

Intra-abdominal hypertension affects multiple systems, including cardiovascular (decreased cardiac output), respiratory (reduced chest wall compliance, hypoxemia), renal (renal vein compression, decreased urine output), and even the brain (elevated intracranial pressure).

What is the role of paracentesis in managing intra-abdominal hypertension?

Paracentesis is a procedure to remove fluid from the abdominal cavity, commonly used when ascites is present. It can rapidly reduce intra-abdominal pressure, improving respiratory, renal, and cardiovascular function.

What are the recommended steps to manage intra-abdominal hypertension and abdominal compartment syndrome?

Management includes neuromuscular blockade, ventilatory support, hemodynamic monitoring, and potentially surgical decompression. In milder cases, decompression with an NG tube may be sufficient, while more severe cases may require surgical intervention like laparotomy.

How does intra-abdominal pressure influence abdominal perfusion pressure?

Abdominal perfusion pressure is calculated as mean arterial pressure minus intra-abdominal pressure. A pressure lower than 60 mmHg indicates poor organ perfusion and a risk of organ dysfunction.

What are the typical symptoms of abdominal compartment syndrome?

Symptoms of abdominal compartment syndrome include difficulty in ventilation, hypoxemia, hypercarbia, hypotension, reduced urine output, and organ dysfunction.

How can intra-abdominal hypertension lead to multi-system organ failure?

As intra-abdominal pressure increases, perfusion to organs decreases, causing reduced cardiac output, respiratory dysfunction, renal failure, and impaired blood flow, ultimately leading to multi-system organ failure if not managed promptly.

Why is early detection of intra-abdominal hypertension crucial?

Early detection allows for timely interventions, such as fluid removal or decompression, preventing progression to abdominal compartment syndrome, which is more difficult to manage and associated with higher complications and mortality.