What is actually Pulse Pressure Variation Easy Guide and Tips

Why Pulse Pressure Variation Is So Helpful During COVID-19

The COVID-19 pandemic has exerted immense pressure on healthcare systems globally and put medical practitioners in an environment requiring the use of advanced therapeutic modalities to treat severely ill patients. One of these vital techniques is Pulse Pressure Variation (PPV), a dynamic marker employed to evaluate fluid responsiveness in patients on mechanical ventilation. In this way, PPV allows clinicians to assess a patient's cardiovascular status better and guide effective fluid therapy and hemodynamic management.

This blog will also discuss why Pulse Pressure Variation contributed so much during COVID-19, its role in critical care, and how it helped optimally manage such severely ill patients.

Understanding Pulse Pressure Variation (PPV)

So, before we discuss its importance, especially during the COVID-19 pandemic, it is important to understand pulse pressure variation (PPV) and how it works.

What Is Pulse Pressure Variation?

PPV is a dynamic parameter used to measure the changes in pulse pressure (the difference between systolic and diastolic blood pressure) during the respiratory cycle in mechanically ventilated patients. Blood volume present in blood vessels during hypovolemia aids in determining the response to fluid administration and is the basis of using this technology in the clinical setting.

How PPV Works

• In mechanical ventilation, negative pressure changes in the chest affect increased venous return and cardiac output.
• If a patient is fluid-responsive, these pressure variations will notably affect pulse pressure.
• A high PPV (i.e., > 13%) suggests that the patient will respond to fluid administration.
• A low positive predictive value (PPV <9%) indicates that the patient will not respond to large amounts of fluids, and excessive fluid administration can be harmful.

Given that COVID-19 patients with ARDS frequently developed acute right heart failure with consequent circulatory instability, the use of PPV enabled direct real-time monitoring and data surrounding the effects of fluid administration on outcomes.

Why Pulse Pressure Variation Was Important During COVID-19

Fluid Responsiveness in the COVID-19 Patient

One of the most difficult questions in treating severe cases of COVID-19 is how much fluid to give the patient. Many ARDS patients with COVID-19 were treated with mechanical ventilation, but giving too much fluid would worsen lung function by increasing pulmonary edema.

• PPV allowed doctors to know whether a patient needed fluids instead of taking a generalized approach.
• By avoiding fluid overload that was not medically indicated, healthcare providers minimized complications such as pulmonary congestion and organ failure.

Optimizing Hemodynamic Stability

Many COVID-19 patients with severe illness experienced hemodynamic instability, which means their blood pressure and circulation fluctuated dangerously. Conventional techniques, such as central venous pressure (CVP) monitoring, were poor indicators, particularly in mechanically ventilated patients.

• PPV offered a better assessment of fluid requirements and helped deliver optimal fluids and vasopressors to maintain blood pressure.
• This prevented them from becoming hypotensive (low blood pressure) or fluid-overloaded, which can result in organ damage.

Minimizing the Hazard of Injury to the Lungs from Ventilators

The sickest patients with COVID-19 frequently develop respiratory failure that calls for mechanical ventilation. On the other hand, ventilator-associated lung injury (VILI) may occur due to insufficient fluid management by a negative pressure change, and lung edema could be aggravated due to increased lung stiffness and inflammation.

• Doctors could micro-manage fluid therapy using Pulse Pressure Variation, putting less strain on the lungs.
• This improved the oxygenation levels while minimizing the risk of mechanical ventilation.

PPV Improves Fluid Monitoring over Traditional Methods

Before introducing PPV, physicians frequently used fixed parameters, such as blood pressure, heart rate, or central venous pressure (CVP), to evaluate fluid requirements. But these methods had their limits:

• Cardiovascular pressure (CVP) and blood pressure readings can be misleading because they don't include real-time changes in heart function.
• In ventilated patients, PPV is more sensitive since it reflects how pulse pressure varies according to the breath, which was shown to be a more accurate predictor of fluid responsiveness.

Better Decision-Making from the Intensive Care Units (ICUs)

During the COVID-19 surge, ICU beds were in high demand, and doctors had to make quick yet accurate decisions regarding patient care. Pulse pressure variation prioritized which patients should receive fluid therapy, as the patients for whom fluid therapy is most beneficial.

• PPV-based monitoring can reduce superfluous fluid administration, reduce complications, and help to make intensive care unit resources available for other critically ill patients.
• This augmentation helped improve the overall patient outcomes and survival rates throughout the pandemic.

Outcomes of Using Pulse Pressure Variation in Critical Care

The success of Pulse Pressure Variation during the COVID-19 crisis highlighted its value in critical care medicine beyond the pandemic. Moving forward, PPV is expected to play a key role in managing patients with:

• Sepsis and septic shock (in which fluid resuscitation is important)
• Post-operative care (to help circulation and recovery)
• Heart failure management (to avoid congestion)
• Advancements in PPV Monitoring Technology

The evolution of medical technology drives the continuous development of non-invasive PPV monitoring devices. This will make PPV even more accessible in emergency settings and resource-limited hospitals worldwide, improving patient care for all.

Summing Up

Pulse Pressure Variation (PPV) is a real-time and reliable demonstration of fluid responsiveness in managing critically ill patients with COVID-19. It facilitates optimal fluid management, hemodynamic stabilization, and complication prevention in ventilated patients. Unlike average methodologies, PPV provides continuous experiences, enabling specialists to make educated choices quickly and effectively. 

The informed lesson from COVID-19 has confirmed that advanced hemodynamic monitoring is a preliminary requirement for the future of medicine, and a definitive improvement has been observed with PPV.