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Published on: March 11, 2017

Correlation between withdrawal symptoms and medication pump residual volume in patients with implantable SynchroMed

Jamal Taha1, Jacques Favre, Michele Janszen

  • 1Division of Neurosurgery, Kettering Medical Center, Dayton, Ohio 45429, USA. jamal.taha@kmcnetwork.org

Neurosurgery
|July 24, 2004
PubMed
Abstract

Insights

Some patients using SynchroMed pumps experience drug withdrawal symptoms before the 2 ml alarm volume. Increasing the alarm volume to 4 ml prevented recurrence, suggesting a potential adjustment for managing drug delivery complications.

Area of Science:

  • Neurology
  • Pharmacology
  • Biomedical Engineering

Background:

  • Implantable SynchroMed pumps are used for continuous drug delivery.
  • The manufacturer recommends an alarm residual volume of 2 ml for these pumps.
  • Drug withdrawal symptoms can occur when medication levels are low.

Purpose of the Study:

  • To determine if patients with SynchroMed pumps experience drug withdrawal symptoms at residual volumes exceeding 2 ml.
  • To identify potential predictors for the development of withdrawal symptoms.
  • To assess the impact of increasing the alarm residual volume on symptom recurrence.

Main Methods:

  • Retrospective review of data sheets for 88 patients with SynchroMed pumps.
  • Analysis of drug withdrawal symptoms, residual volumes, drug characteristics, and patient factors.
  • Comparison of withdrawal symptom onset relative to pump residual volume.

Main Results:

  • 24% of patients (21/88) developed withdrawal symptoms before the residual volume reached 2.7 ml (mean).
  • Symptoms appeared 1-7 days prior to the alarm volume and persisted until pump refill.
  • Increasing the alarm volume to 4 ml eliminated symptom recurrence in all patients.

Conclusions:

  • Drug withdrawal symptoms can manifest in some patients with SynchroMed pumps at residual volumes above 2 ml.
  • No specific factors were identified to predict the occurrence of these withdrawal symptoms.
  • Raising the alarm residual volume to 4 ml effectively prevented the recurrence of withdrawal symptoms.

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