What are the early ECG (electrocardiogram) changes in a case of non-bilious vomiting due to gastric outlet obstruction?

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From the Research

Early ECG changes in non-bilious vomiting due to gastric outlet obstruction typically include ST segment depression, as this is a common manifestation of hypokalemia, which is often present in such cases 1. The primary mechanism behind these ECG changes involves the loss of gastric acid and potassium through persistent vomiting, leading to metabolic alkalosis and hypokalemia. Some key points to consider include:

  • The severity of ECG changes correlates with the duration and intensity of vomiting episodes
  • Patients may develop hypochloremia and hyponatremia in addition to hypokalemia
  • Treatment should focus on correcting the underlying obstruction and addressing fluid and electrolyte imbalances, particularly potassium replacement
  • Intravenous fluid resuscitation with potassium chloride supplementation is typically required, with careful monitoring of electrolyte levels
  • These ECG changes are generally reversible once the electrolyte abnormalities are corrected and the gastric outlet obstruction is resolved 2. Other options like elevated T wave, P wave prominent, and T wave sagging may also be seen in various conditions, but ST segment depression is the most relevant early ECG change in the context of non-bilious vomiting due to gastric outlet obstruction, as supported by the study on electrocardiographic manifestations in severe hypokalemia 1.

References

Research

Electrocardiographic manifestations in severe hypokalemia.

The Journal of international medical research, 2020

Research

ECG of the Month: ECG in a 30-Year-Old Woman.

The Journal of the Louisiana State Medical Society : official organ of the Louisiana State Medical Society, 2015

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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