What is the Queckenstedt effect?

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What is the Queckenstedt Effect?

The Queckenstedt effect (or Queckenstedt's test) is the physiological phenomenon where bilateral compression of the internal jugular veins during lumbar puncture causes a rapid rise in cerebrospinal fluid (CSF) pressure in the lumbar subarachnoid space when there is free communication throughout the spinal canal, but produces an absent or diminished pressure response when spinal subarachnoid obstruction is present. 1

Historical Context and Mechanism

  • Hans H. G. Queckenstedt first described this test in 1916 as a method to detect spinal CSF space obstruction through lumbar CSF pressure measurements in paraplegic patients 1
  • The test works by applying bilateral jugular vein compression during lumbar puncture and observing consecutive changes in lumbar CSF pressure 1
  • In 1922, James B. Ayer provided proof of concept by performing simultaneous cisternal and lumbar CSF pressure measurements, demonstrating that cisternal pressure remained responsive even when lumbar pressure did not rise in cases with spinal block 1

Normal Physiological Response

  • In patients without subarachnoid obstruction, jugular compression produces a sudden steep rise in lumbar CSF pressure that gradually slows, then rapidly returns to pre-compression level after release of compression 2
  • The normal pressure pattern shows upward convexity-downward concavity, resembling a parabola-like or exponential curve 2
  • This pattern reflects rapid caudad movement of CSF when sitting up and craniad movement when lying down in patients with free communication 3
  • The pressure changes are nearly identical in three different neck positions (neutral, flexion, and extension) when the subarachnoid space is patent 2

Abnormal Response Indicating Obstruction

  • Findings are rated as normal, indicative of incomplete spinal block, or complete spinal block based on the pressure response pattern 1
  • In patients with cervical spondylotic radiculopathy, the test shows nearly normal pressure patterns except for some loss of upward convexity during neck extension and neutral positions 2
  • Complete absence of pressure rise indicates complete subarachnoid obstruction, while diminished or delayed response suggests partial obstruction 1, 2

Clinical Applications

  • The test became widely adopted as a routine diagnostic procedure for testing spinal canal obstruction and was refined until the 1960s 1
  • It can confirm epidural puncture during anesthesia procedures by assessing indirect changes in epidural pressure, with sensitivity of 92.0% and specificity of 100% 4
  • When increased epidural pressure is observed during bilateral jugular compression, epidural puncture is reliably confirmed 4
  • The test remains effective even in patients with potential spinal canal narrowing, including cervical spinal stenosis 4

Modern Relevance and Decline

  • Interest in Queckenstedt's test significantly declined with the development of non-invasive spinal computed tomography and magnetic resonance imaging, eventually disappearing from textbooks and clinical routine 1
  • However, at the beginning of the 21st century, renewed interest emerged in revealing the biomechanical properties of CSF through advanced recording and computational techniques to complement spinal imaging 1
  • The test provided a physiological framework for understanding spinal cord compression that remains valid today 1

Pathophysiological Insights

  • Subarachnoid space obstruction leads to increased fluid flow within spinal cord tissue, presenting as increased flow in perivascular spaces of arterioles and venules, and the basement membranes of capillaries 5
  • CSF tracer studies demonstrate that tracer is found predominantly in perivascular spaces of arterioles and venules, as well as capillary basement membranes, highlighting the importance of perivascular pathways in spinal cord fluid transport 5
  • Increased fluid retention in the spinal cord with obstructed subarachnoid space may be a critical step in the development of post-traumatic syringomyelia 5

References

2
Research

[Queckenstedt test--pressure pattern analysis in spinal subarachnoidal block].

Rinsho shinkeigaku = Clinical neurology, 1990

5
Research

Effect of extradural constriction on CSF flow in rat spinal cord.

Fluids and barriers of the CNS, 2019

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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.

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