Can Ketamine affect activated Partial Thromboplastin Time (aPTT)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 28, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Ketamine does not significantly affect activated partial thromboplastin time (aPTT). Based on available clinical evidence, ketamine administration has not been shown to cause clinically relevant alterations in coagulation parameters including aPTT 1. This means that when administering ketamine for anesthesia, analgesia, or treatment of depression at standard therapeutic doses (typically 0.5-2 mg/kg IV for anesthesia induction, 0.1-0.5 mg/kg IV for analgesia, or 0.5 mg/kg IV for depression), clinicians do not need to anticipate changes in coagulation status related to the medication itself.

Mechanism of Action

Ketamine primarily works as an NMDA receptor antagonist affecting central nervous system function rather than interacting with the coagulation cascade 1. This is important because it means ketamine can generally be used safely in patients with coagulation disorders or those on anticoagulant therapy without directly worsening coagulation parameters. However, always consider the patient's complete clinical picture, as the condition requiring ketamine treatment might independently affect coagulation status.

Clinical Considerations

Some key points to consider when using ketamine include:

  • Monitoring for emergence reactions, which can be minimized with the use of midazolam 1
  • Avoiding use in patients with ischemic heart disease, cerebrovascular disease, or hypertension due to its potential to increase heart rate, blood pressure, and cardiac output 1
  • Being aware of the potential for ketamine to cause respiratory depression, although this is rare and typically brief 1

Coagulation Parameters

The provided evidence does not support a significant effect of ketamine on aPTT or other coagulation parameters 1. Therefore, ketamine can be used without expecting significant alterations in coagulation status, making it a viable option for patients with various clinical conditions, including those requiring anticoagulation therapy.

From the Research

Effect of Ketamine on aPTT

  • There are no research papers to assist in answering this question, as none of the provided studies 2, 3, 4, 5, 6 investigate the effect of ketamine on activated partial thromboplastin time (aPTT).
  • The studies provided focus on various aspects of coagulation and aPTT, including monitoring anticoagulation therapy 2, interpreting abnormal coagulation test results 3, evaluating coagulation waveform analysis 4, investigating coagulation time 5, and the influence of factor XII deficiency on aPTT 6.
  • However, none of these studies mention ketamine or its potential impact on aPTT, making it impossible to provide an evidence-based answer to the question.

Professional Medical Disclaimer

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.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.