What Is Acid-Base Balance and Why Does It Matter?

Your body carefully maintains a blood pH between 7.35 and 7.45, ensuring all systems function properly. If the pH level drops below this range, it results in acidosis (excess acid). If it rises above this range, it causes alkalosis (excess base).

Heatstroke can disrupt this balance, leading to either acidosis or alkalosis, depending on how the body reacts to extreme heat and fluid loss.

Acidosis in Heatstroke: The Most Common Complication

Acidosis is the dominant acid-base disorder in severe heatstroke cases. Here’s why:

Lactic Acidosis: When Oxygen Supply Fails

Heatstroke often leads to dehydration and low blood pressure, reducing oxygen delivery to tissues. When oxygen is scarce, cells switch to anaerobic metabolism, producing excess lactic acid, which leads to lactic acidosis.

This explains why heatstroke patients often have elevated lactate levels in blood tests, indicating metabolic acidosis.

Kidney Dysfunction: The Acid Buildup Problem

Heatstroke can cause acute kidney injury (AKI), impairing the kidneys’ ability to filter out acidic waste products like hydrogen ions. As a result, these acids accumulate in the blood, worsening metabolic acidosis.

Rhabdomyolysis: Muscle Breakdown Releases Acidic Compounds

Severe heatstroke can lead to rhabdomyolysis, a condition where muscle fibers break down and release myoglobin and acidic byproducts into the bloodstream. This increases acid levels, contributing to metabolic acidosis.

Electrolyte Imbalances: The Role of Potassium

Prolonged exposure to heat can cause excessive sweating and dehydration, leading to imbalances in sodium, potassium, and bicarbonate levels. High potassium levels (hyperkalemia) can further disrupt the acid-base balance, pushing the body toward acidosis.

Alkalosis in Heatstroke: Why It Happens Early On

Although acidosis dominates in severe cases, heatstroke can initially cause respiratory alkalosis in some patients. Here’s how:

Hyperventilation: Breathing Too Fast

In response to heat, the body increases its breathing rate (hyperventilation) to cool down. This rapid breathing leads to excessive carbon dioxide (CO₂) loss, which can cause respiratory alkalosis (a temporary shift towards alkalinity).
However, this is usually short-lived. As heatstroke progresses and dehydration worsens, the body shifts towards metabolic acidosis, which becomes the dominant condition.

Early Stages vs. Late Stages of Heatstroke

Early stage: Increased breathing → CO₂ loss → Respiratory alkalosis
Late stage: Dehydration, kidney failure, and muscle breakdown → Metabolic acidosis

Preventing Acid-Base Imbalance in Heatstroke

To reduce the risk of acidosis and alkalosis in heatstroke, follow these essential steps:

✅ Stay hydrated – Drink plenty of fluids to support circulation and kidney function.
✅ Replenish electrolytes – Use electrolyte-rich drinks to prevent imbalances.
✅ Monitor breathing – If you feel dizzy or lightheaded, take a break and rehydrate.
✅ Avoid excessive heat exposure – Limit physical activity in extreme temperatures.
✅ Recognize warning signs – Symptoms like confusion, muscle weakness, or rapid breathing indicate a problem—act fast!

Conclusion: Acidosis and Alkalosis in Heatstroke Both Play a Role in Heatstroke

While alkalosis may occur in the early stages due to hyperventilation, acidosis is the primary acid-base disturbance in severe heatstroke cases.

🔹 Respiratory alkalosis happens early on when breathing rate increases.
🔹 Metabolic acidosis becomes dominant as dehydration, kidney failure, and muscle breakdown progress.

Understanding these changes can help in better managing and preventing heatstroke complications. So, next time you’re in extreme heat, remember—it’s not just about cooling down, but also maintaining your body’s internal balance!

💡 Have you ever experienced heat-related symptoms? Share your story in the comments and let’s discuss how to stay safe in extreme heat! 🌞💧