From the Guidelines
Volume overload is primarily caused by conditions that lead to excessive fluid in the circulatory system, including kidney dysfunction, heart failure, excessive intravenous fluid administration, and certain medications or diseases that cause sodium and water retention. The main causes of volume overload can be categorized into several key areas:
- Kidney dysfunction, such as acute or chronic kidney disease, which impairs the body's ability to excrete excess fluid and sodium 1.
- Heart failure itself, as the weakened heart cannot effectively pump blood, leading to fluid backing up in the lungs and body tissues 1.
- Excessive intravenous fluid administration in hospital settings, particularly in critically ill patients, is another common cause.
- Certain medications like nonsteroidal anti-inflammatory drugs (NSAIDs) and some blood pressure medications can contribute by causing sodium and water retention.
- Liver cirrhosis leads to volume overload through complex mechanisms involving decreased albumin production and portal hypertension.
- Endocrine disorders such as hypothyroidism and Cushing's syndrome can cause fluid retention, as can severe malnutrition which reduces plasma protein levels.
- Pregnancy normally increases blood volume, but can sometimes lead to pathological volume overload. It's also important to note that volume overload can be a result of high output states mimicking heart failure, such as anaemia, thyrotoxicosis, septicaemia, liver failure, arteriovenous shunts, Paget’s disease, and beri-beri 1. Treatment typically involves addressing the underlying cause while managing symptoms through fluid restriction, diuretics like furosemide (20-80mg daily), and in severe cases, mechanical fluid removal through ultrafiltration or dialysis. In patients with chronic heart failure, the clinical progression of the disease is characterized by the need for increasing doses of diuretics, as the absorption of the drug may be delayed by bowel edema or intestinal hypoperfusion, and the delivery of the drug and the response to a given intratubular concentration may be impaired by a decline in renal perfusion 1. Volume overload is a significant concern in patients with kidney disease, as it can lead to hypertension, which is a major risk factor for cardiovascular disease 1. The prevalence of heart failure, which is often associated with volume overload, is increasing due to the ageing of the population, the success in prolonging survival in patients suffering coronary events, and the success in postponing coronary events by effective prevention in those at high risk or those who have already 1.
From the Research
Causes of Volume Overload
The causes of volume overload can be attributed to various factors, including:
- Excess total body sodium and water with expansion of extracellular fluid volume, characterizing common disorders such as congestive heart failure, end-stage liver disease, chronic kidney disease, and nephrotic syndrome 2
- Medication non-compliance, excessive salt intake, comorbidities, and/or disease progression in acute decompensated heart failure (ADHF) 3
- End-stage renal disease (ESRD) patients, where volume overload is directly related to numerous complications including resistant hypertension, cardiac hypertrophy, congestive heart failure or arterial stiffness, among others 4
- Complex pathophysiology of congestion in congestive heart failure, involving the dynamics of interstitial and intravascular fluid compartment interactions and fluid redistribution from venous splanchnic beds to central pulmonary circulation 5
- A multitude of disease states, as well as a complication of many medical therapies, especially concerning in critically ill patients in the intensive care unit when persistent past the first few days of admission 6
Common Disorders Associated with Volume Overload
Some common disorders associated with volume overload include:
- Congestive heart failure
- End-stage liver disease
- Chronic kidney disease
- Nephrotic syndrome
- Acute decompensated heart failure (ADHF)
- End-stage renal disease (ESRD)
Factors Contributing to Volume Overload
Factors contributing to volume overload include:
- Excess sodium and water intake
- Medication non-compliance
- Comorbidities
- Disease progression
- Medical therapies
- Kidney disease, particularly in the setting of chronic kidney disease