Hippocampal neurons are damaged by caffeine-augmented electroshock seizures

Augmentation strategies in electroconvulsive therapy

Electroconvulsive therapy (ECT) is a highly effective treatment, but strategies to enhance therapeutic outcomes are occasionally needed. This review examines the evidence for approaches used for enhancing seizure production: hyperventilation, pretreatment with xanthines, and use of remifentanil or ketamine in ECT anesthesia. Hyperventilation may be a useful strategy to enhance seizure production, but its effects on ECT outcomes have not been systematically studied and require further research. Pretreatment with caffeine, theophylline or aminophylline (xanthines) prolongs the duration of ECT seizures but has not been clearly shown in controlled trials to increase efficacy. Caution is also warranted because their use may be associated with significant adverse effects. There are case reports of the usefulness of remifentanil in assisting seizure induction by reducing the dose of barbiturate anesthetic required, but there are no controlled data on whether it independently enhances efficacy outcomes. Preliminary evidence suggests that ketamine and ECT may have synergistic antidepressant effects, although this needs to be further examined in randomized controlled trials.

Evidence for the involvement of the adenosine A(2A) receptor in the lowered susceptibility to pentylenetetrazol-induced seizures produced in mice by long-term treatment with caffeine

Long-term caffeine intake has been reported to decrease the susceptibility to convulsants in mice. Occurrence of seizures following long-term oral administration of caffeine (0.3g/l) was investigated using adenosine A(2A) receptor knockout (A(2A)R KO) and control (A(2A)R WT) mice. Clonic seizures induced by acute pentylenetetrazol (PTZ, 50mg/kg i.p.) were significantly attenuated in adenosine A(2A)R KO mice drinking only water and reduced by a 14-day caffeine treatment in adenosine A(2A)R WT mice. In addition we showed a protecting effect of a 21-day caffeine treatment in A(2A)R WT mice against kindled seizures induced by PTZ in an increasing dose schedule. Summing up, these protective effects against PTZ-induced seizures occurring when adenosine A(2A)R is absent or chronically blocked by a relevant dose of caffeine may be related to a decreased neuronal excitability.

Augmentation of electroconvulsive therapy seizures with sleep deprivation

Electroconvulsive therapy (ECT) is the fastest and most effective treatment for severe or treatment-resistant affective and psychotic disorders. Its therapeutic effect is obtained through a generalized tonic-clonic seizure of adequate duration. Several factors (older age, male gender, and the sessions of ECT themselves) increase seizure threshold and reduce seizure time. In our work, sleep deprivation was used as a strategy to enhance the ECT seizure. A matched sample design was conducted on the basis of the following variables: gender, age range, and seizure threshold. After the first ECT, when the initial seizure threshold was measured, subjects were assigned to ECT (electroconvulsive therapy) or SD+ECT (sleep deprivation + electroconvulsive therapy). Changes in the variable of seizure threshold were studied in both groups during the treatment course. A nonparametric analysis was implemented for 2 independent groups. During the treatment course, the SD+ECT group showed a decreased seizure threshold, from 190.4 mC in the first ECT session to 176.4 mC in the last ECT session, whereas the ECT group showed an increased seizure threshold, increasing from 190.4 mC to 321.91 mC. Sleep deprivation is an effective and safe technique used to lower the seizure threshold of ECT and to obtain an adequate seizure time without increasing the energy applied.

ECT in the presence of brain tumor and increased intracranial pressure: evaluation and reduction of risk

The presence of brain tumor and increased intracranial pressure has long been considered an absolute contraindication to electroconvulsive therapy. Recently, however, the American Psychiatric Association Task Force Report questioned the absolute nature of this contraindication and recommended a detailed evaluation of the risk-benefit ratio and measures to decrease the risks involved in treatment of affected persons. After a careful review, electroconvulsive therapy was administered to a 61-year-old patient who had severe medication-resistant major depression and a left temporal anaplastic astrocytoma with brain edema. Special attention was given to reduce intracranial pressure and minimize neurologic side effects. A course of eight nondominant unilateral electroconvulsive therapy treatments improved the depression significantly, without serious complications at the 4-month follow-up examination. With appropriate modifications, electroconvulsive therapy may be considered a treatment option even in the presence of clinical evidence of increased intracranial pressure. Further studies are needed to assess and minimize risks of electroconvulsive therapy in association with brain tumor.

The neuropathological effects of antipsychotic drugs

In addition to their neurochemical effects, antipsychotic (neuroleptic) drugs produce structural brain changes. This property is relevant not only for understanding the drugs' mode of action, but because it complicates morphological studies of schizophrenia. Here the histological neuropathological effects of antipsychotics are reviewed, together with brief mention of those produced by other treatments sometimes used in schizophrenia (electroconvulsive shock, lithium and antidepressants). Most data come from drug-treated rats, though there are also some human post-mortem studies with broadly congruent findings. The main alteration associated with antipsychotic medication concerns the ultrastructure and proportion of synaptic subpopulations in the caudate nucleus. In rats, synapses and dendrites in lamina VI of the prefrontal cortex are also affected. The changes are indicative of a drug-induced synaptic plasticity, although the underlying mechanisms are poorly understood. Similarly, it is unclear whether the neuropathological features relate primarily to the therapeutic action of antipsychotics or, more likely, to their predisposition to cause tardive dyskinesia and other motor side-effects. Clozapine seems to cause lesser and somewhat different alterations than do typical antipsychotics, albeit based on few data. There is no good evidence that antipsychotics cause neuronal loss or gliosis, nor that they promote neurofibrillary tangle formation or other features of Alzheimer's disease.