Initial Seizure Threshold in Brief-Pulse Bilateral Electroconvulsive Therapy in Patients with Schizophrenia or Schizoaffective Disorder

Molecular and cellular mechanisms leading to catatonia: an integrative approach from clinical and preclinical evidence

This review aims to describe the clinical spectrum of catatonia, in order to carefully assess the involvement of astrocytes, neurons, oligodendrocytes, and microglia, and articulate the available preclinical and clinical evidence to achieve a translational understanding of the cellular and molecular mechanisms behind this disorder. Catatonia is highly common in psychiatric and acutely ill patients, with prevalence ranging from 7.6% to 38%. It is usually present in different psychiatric conditions such as mood and psychotic disorders; it is also a consequence of folate deficiency, autoimmunity, paraneoplastic disorders, and even autistic spectrum disorders. Few therapeutic options are available due to its complexity and poorly understood physiopathology. We briefly revisit the traditional treatments used in catatonia, such as antipsychotics, electroconvulsive therapy, and benzodiazepines, before assessing novel therapeutics which aim to modulate molecular pathways through different mechanisms, including NMDA antagonism and its allosteric modulation, and anti-inflammatory drugs to modulate microglia reaction and mitigate oxidative stress, such as lithium, vitamin B12, and NMDAr positive allosteric modulators.

Dosing methods in electroconvulsive therapy: should the Scandinavian time-titration method be resumed?

AIM

To describe and evaluate the different dosing methods in ECT, and bringing back into focus the Scandinavian time-titration method.

METHOD

A narrative, unsystematic, and selective review and discussion.

RESULTS

There are five dosing methods: 1) The Scandinavian time-titration to tonic convulsion, using low-frequency pulses and a long maximal pulse train duration, was highly efficacious with right unilateral (RUL) ECT, comparable to bitemporal (BT) ECT. However, the device used went out of production in the 1990s. Because US devices until 1990 had a short maximal pulse train duration, time-titration went out of use. 2) Fixed high dosing at 50-100% of the device's maximal output, and 3) Formula-based dosing, initially the Age method, long prevailed in USA. Later, the Half-Age method was introduced for BT ECT. 4) Charge-dosing as a multiple of titrated seizure threshold (ST) demonstrated RUL and BT ECT to have comparable outcomes when dosed about six and two times the ST, respectively. 5) Dosing from benchmark is based on a high dose at the first session, to ensure a high peak heart rate and tonic-clonic convulsions. In later sessions the lowest dose producing similar outcomes is chosen.

CONCLUSIONS

No dosing method is documented superior to the others. Seizure threshold-based and benchmark dosing seems to be more accurate than fixed high and formula-based dosing. However, time-titration dosing makes it possible to adjust the dose at every session, and may be the most efficient method.