The purpose of the electrical stimulus in ECT is to induce a generalized grand mal type of seizure.The seizure produced is not an all- or-nothing phenomenon.
seizures can be monitored both by observingthe ictal motor response (convulsion)monitoring ictal EEG activity (the electrophysiological activity of the brain occurring during theSeizure) , ( use muscle relaxant)EEG seizure activity is typically 10–20 seconds longer.
The intensity of convulsive motor activity is influenced by two factors: the dose of muscle relaxant (generally succinylcholine) intensity of the electrical stimulusMost physicians use a practiceknown as the cuff technique to allow the motor convulsion to be monitored after giving muscle relaxant
the cuff technique to allow the motor convulsion to be monitored.Just before the muscle relaxant is administered, a blood pressure cuff is placed on a distal extremity(wrist or ankle) and inflated well above the systolic pressure (about 200 mm Hg).This activity procedure prevents the flow of muscle relaxant distal to the cuff and enables unblocked muscles to manifest convulsive
.The ECT stimulus and the inducedseizure both exert cardiovascular,effectsprimarily through the direct neuronal transmission fromthe hypothalamus to the heartvia parasympathetic tracts (the vagus nerve)and sympathetictracts (primarily in the spinal cord).The activation of the parasympathetic system causes adecrease in bloodpressure and heart rate. t
The cardiovascular response pattern can best be describedas a four-stage process,involving shifts from parasympathetic to sympathetic to parasympathetic to sympathetic phases The activation of the sympathetic system produces opposite effects: blood pressure, venous pressure, and heart rate increase, resulting in an overall acceleration of cardiac output
Missed Seizureswhen no motor and ictal evidence of seizure activity is seen following the electrical stimulus,
Causes Insufficientstimulus intensity Premature termination of stimulus Poor electrode contact with the skin Patient’s high intrinsic seizure threshold Hypercarbia due to hypoventilationNB the patient should be restimulated within 20–30 seconds, using a 25%–125% increase in stimulus intensity
Seizures of “inadequate” duration Restimulation (should be delayed for 30–60 sec)
Evidence suggests that missed or inadequate seizures occurring at maximum stimulus intensity decrease the likelihood that the patient will respond to treatment. When these phenomena occur, efforts should be directed at: Decreasing the seizure threshold Increasing the seizure duration or both (Krystal et al. 2000).
Presently, four methods of seizure enhancement are commonly used: Decreasing the anesthetic dosage (if possible and if the agent used has anticonvulsant properties) Hyperventilation (inducing hypocarbia) Caffeine (and other adenosine receptor antagonists) Ketamin anesthesia (Weiner et al. 1991).
Seizure activity lasting longer than 3 minutes (American Psychiatric Association 2001).
1) At the first treatment2) During benzodiazepine withdrawal3) In patients in whom proconvulsant medications (e.g., caffeine, theophylline) and lithium4) In patients who have epilepsy or preexisting paroxysmal EEG activity
Inaddition to making the decisions of ECT, the practitioner must also make a determination of: How frequently the seizures should be induced (i.e., the interval between treatments) How many treatments should be administered in the treatment course.
Most ECT treatments are given three times a week whereas in other countries they may be administered twice weekly. Increased frequency is associated with a more rapid response, it may also be associated with increased cognitive side effects A three-times-weekly schedule appears to be an acceptable
A total number of treatments averaging between six and twelve but no exact number The number of treatments will vary according to the individual and severity of medical condition.
After the conclusion of a course of ECT, three options are available for continued treatment:r Administration of applicable psychotropic medications (e.g., antidepressant, antimanic, and/or antipsychotic agent)r Administration of continuation ECTf Psychotherapy combined with either medication or continuation ECT.
A fourth option, involving the use of both continuation medication and ECT, may be necessary for patients with a history of failure of prophylaxis with either treatment alone.
Multiple psychiatric disorders respond to maintenance ECT including: major depressive disorder psychotic depression bipolar disorder and schizoaffective disorder (Birkenhager et al. 2005).
Use of maintenance ECT in the geriatric population is also well documented (Thienhaus et al. 1990).
Particular forms of schizophrenia (catatonia, refractory positive symptoms) may also be responsive to the combination of ECT and antipsychotic medication (Shimizu et al. 2007; Suzuki et al. 2006)
A typical arrangement would involve weekly ECT for 4 weeks, then incremental increases in the interval between ECT treatments to once a month over the next few months (Clarke et al. 1989).
مــادة )03( : ل يجوز إجراء العلج الكهربائى اللزم لحالة المريضالنفسى إل تحت تأثير مخدر عام وباسط للعضلت ، ويتعين الحصول على موافقته على ذلك كتابة بناء على إرادة حره مستنيره وبعد إحاطته علما بطبيعة هذا العلج والغرض منه ،والثار الجانبيه التى قد تنجم عنه، والبدائل العلجيه له، فإذا رفض المريضالخاضع لجراءات الدخول والعلج اللزامى هذا النوع من العلج وكان لزما لحالته فرض عليه بعد إجراء تقييم طبى مستقل.