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Undulating toe movements in brain death
G Saposnik1, J Mauriño, R Saizar
1Movements in Brain Death Study Group, Department of Neurology, Hospital JM Ramos Mejía, Universidad de Buenos Aires, Buenos Aires, Argentina. gsaposnik@yahoo.com
Abstract:
For many years, death implied immobility. Nevertheless, there are anecdotal reports of spontaneous or reflex movements (SRMs) in patients with Brain death (BD). The presence of some movements can preclude the diagnosis of BD, and consequently, the possibility of organ donation for transplantation. McNair and Meador [(1992), Mov Dord7: 345-347] described the presence of undulating toe flexion movements (UTF) in BD patients. UTF consists in a sequential brief plantar flexion of the toes. Our aim was to determine the frequency, characteristics and predisposing factors of UTF movements in a prospective multicenter cohort study of patients with BD. Patients with confirmed diagnosis of BD were assessed to evaluate the presence of UTF using a standardized protocol. All patients had a routine laboratory evaluation, CT scan of the head, and EEG. Demographic, clinical, hemodynamic and blood gas concentration factors were analyzed. amongst 107 BD patients who fulfilled the AAN requirements, 47 patients (44%) had abnormal movements. UTF was observed in 25 (23%) being the most common movement (53%). Early evaluation (OR 4.3, CI95% 1.5-11.9) was a predictor of UTF in a multivariate regression model. The somato-sensory evoked potential (SSEPs) as well as brainstem auditory evoked potentials (BAEPs) did not elicit a cortical response in studied patients with UTF. This spinal reflex is probably integrated in the L5 and S1 segments of the spinal cord. Abnormal movements are common in BD, being present in more than 40% of individuals. UTF was the most common spinal reflex. In our sample, early evaluation was a predictor of UTF. Health care professionals, especially those involved in organ procurement for transplantation, must be aware of this sign. The presence of this motor phenomenon does not preclude the diagnosis of BD.
Insights
Undulating toe flexion movements (UTF) are common in brain death (BD) patients, occurring in 23% of cases. Early evaluation predicts UTF, a spinal reflex that does not preclude BD diagnosis or organ donation.
Area of Science:
- Neurology
- Neurosurgery
- Critical Care Medicine
Background:
- Spontaneous or reflex movements (SRMs) have been anecdotally reported in patients with brain death (BD).
- The presence of SRMs can complicate the diagnosis of BD and impact organ donation for transplantation.
- Undulating toe flexion (UTF) movements, a sequential brief plantar flexion of the toes, have been previously described in BD patients.
Purpose of the Study:
- To determine the frequency, characteristics, and predisposing factors of UTF movements in a prospective multicenter cohort study of patients with BD.
- To clarify whether UTF movements preclude the diagnosis of BD and affect organ donation potential.
Main Methods:
- A prospective multicenter cohort study involving 107 patients with confirmed BD diagnosis according to AAN requirements.
- Standardized assessment for UTF movements, routine laboratory evaluation, CT scan of the head, EEG, SSEPs, and BAEPs.
- Analysis of demographic, clinical, hemodynamic, and blood gas concentration factors as potential predictors of UTF.
Main Results:
- 47% of BD patients exhibited abnormal movements, with UTF being the most common (23% of all BD patients, 53% of those with abnormal movements).
- Early evaluation was identified as a significant predictor of UTF (OR 4.3, CI95% 1.5-11.9) in a multivariate regression model.
- SSEPs and BAEPs did not elicit a cortical response in patients with UTF, suggesting a spinal cord integrated reflex (L5 and S1 segments).
Conclusions:
- Abnormal movements, particularly UTF, are common in BD patients and do not preclude the diagnosis.
- Early evaluation is a predictor of UTF, highlighting the need for awareness among healthcare professionals involved in organ procurement.
- UTF is a spinal reflex that should be recognized and differentiated from other neurological signs when assessing BD.
