Introduction:
According to statistics, up to 10 % of the population have a mental illness, and just 1 % of those have a serious psychiatric disorder. It has been shown that psychotic individuals on chronic antipsychotic therapy had a higher postoperative mortality rate. Arrhythmias, hypotension, protracted narcosis or coma, hyperpyrexia, postoperative ileus, and postoperative disorientation are adverse reactions that can occur during anesthesia. Patients with persistent psychosis also exhibit hypopituitarism, hypoadrenalism, autonomic nerve dysfunction, immune system abnormalities, and water intoxication. Communication with the patient, simultaneous pathology in chronic psychiatric patients, and disorders of the endocrine, immunological, and cardiovascular systems are just a few of the potential challenges that anesthesiologists may face.
What Are Psychiatric Disorders?
The most common psychiatric disorders are:
1. Depression: Depression is the most prevalent psychiatric condition and is characterized by sorrow and hopelessness. Although there are many contributing factors, pharmacological therapy is predicated on the assumption that dopamine, norepinephrine, and serotonin deficiencies in the brain or changed receptor activity might develop depression. These kinds of disorders are treated with antidepressant drugs and some people also receive electroconvulsive therapy when they are resistant to antidepressants. The most common antidepressants are:
- Tricyclic antidepressants (TCA).
- Selective serotonin reuptake inhibitors (venlafaxine and mirtazapine).
- Monoamine oxidase inhibitors (MAOIs).
2. Withdrawal Syndrome: Discontinuation syndrome or withdrawal symptoms develops only after abrupt cessation of antidepressant drugs. The adverse effects begin a few days after discontinuing the antidepressant suddenly, last for a short time (a few days to three weeks), and subside if the antidepressant is restarted. The most common adverse effects of withdrawal syndrome are:
- Nausea.
- Diarrhea.
- Abdominal pain.
- Sleep disturbances.
- Sweating.
- Fatigue.
- Headache.
- Anxiety.
- Irritability.
3. Serotonin Syndrome: It is manifested by increased levels of serotonin within the brain and spinal cord, resulting in life-threatening conditions. The major cause of serotonin syndrome involves the administration of antidepressant drugs, dextromethorphan, tramadol, and pethidine. The most typical symptoms of serotonin syndrome are:
- Change in behavior, such as agitation and disorientation.
- Enhanced motor activity.
- Autonomic imbalance.
- Hyperthermia.
- Tachycardia.
- Diarrhea.
- Rarely, it may also result in arrhythmias, coma, rhabdomyolysis, renal failure, seizures, and death.
4. Bipolar Disorder: Bipolar disorder is characterized by significant mood swings which are often treated with a mood stabilizer like lithium and valproate. Lithium carbonate is used to treat manic depression, however, it is more useful in avoiding mania than in treating depression. Since lithium prevents norepinephrine, epinephrine, and dopamine from being released from the brainstem, it prolongs neuromuscular blockade and may reduce the need for anesthesia.
5. Schizophrenia: Schizophrenia is the most prevalent psychotic mental illness. An excess of dopaminergic neurological activity is considered to be the contributing factor to this condition. Schizophrenia is often treated with antipsychotic drugs. Antipsychotic medication prior to surgery increases the susceptibility of schizophrenic individuals to the hypotensive effects of general anesthesia. On the other hand, stopping antipsychotics may lead to an increase in episodes of psychotic symptoms like agitation and hallucinations. As sudden discontinuation from antipsychotics may cause the return of psychotic symptoms, people with persistent schizophrenia should continue taking them prior to surgery.
What Are the Anesthetic Considerations With Psychiatric Drugs?
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Tricyclic Antidepressants (TCA): It is an antidepressant drug by which the patients could respond differently to medications given during the perioperative anesthetic phase. The increasing anesthetic drug may lead to increased neurotransmitter availability in the central nervous system, and a high range of response is evaluated in both sympathetic stimulation and indirectly acting vasopressors when anesthetic agents interact with tricyclic antidepressant medications. Prolonged use of tricyclic antidepressants reduces cardiac catecholamines, which increases their impact on the heart's functioning. However, Keeping the sympathetic nervous system from being stimulated during anesthesia and surgery is crucial. Direct-acting acting medications, such as phenylephrine, are advised if hypotension develops and vasopressors are indicated. A minimal dose is recommended to reduce an excessive hypertensive reaction.
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Selective Serotonin Reuptake Inhibitors (SSRI): SSRIs are employed to treat mild to moderate depression. It prevents the reuptake of serotonin at presynaptic membranes. Fluoxetine is one of the most effective SSRIs at inhibiting specific liver cytochrome P-450 enzymes. The adverse effects of these drugs include sleeplessness, irritability, and headache. As a result, it may increase the plasma levels of drugs including warfarin, theophylline, phenytoin, and benzodiazepines because clearance of the drug depends on hepatic metabolism. Additionally, the SSRIs enzyme system is also involved in the metabolism of certain cardiac antidysrhythmic medications, and fluoxetine's suppression may enhance the effects of these medications. To avoid discontinuation syndrome, SSRIs should be taken during the perioperative period. and the drugs like pethidine, tramadol, pentazocine, and dextromethorphan should be avoided
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Monoamine Oxidase Inhibitors (MAOIs): An antidepressant drug acts by inhibiting the metabolism of norepinephrine and serotonin by the use of the MAO enzyme. As a result, increased levels of norepinephrine and serotonin were observed at the receptor site. While anesthesia-maintaining MAOIs have hazardous effects, these risks can be reduced with proper anesthesia technique and must be evaluated against the risks of recurrence and discontinuation syndrome. When MAOI is to be withdrawn, doses should be gradually decreased after receiving a standard psych assessment. It is best to avoid postponing surgery and to resume treatment as soon as feasible after surgery. It is advised to avoid sympathetic stimulation while treating a patient under MAOIs. Intravenous fluids should be administered to manage hypotension initially, followed by judicious phenylephrine doses.
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Antipsychotic Drugs: Antipsychotic medications are still the primary curative option for schizophrenia. Antipsychotic medications can have significant side effects for anesthesiologists, such as α-adrenergic blockade that results in postural hypotension, prolonged QT intervals (duration of ventricular electrical systole in ECG), seizures, an increased level of liver enzymes, impaired temperature regulation, drowsiness, and Parkinsonism-like symptoms. Despite this, drug-induced drowsiness may reduce the need for anesthesia. The antipsychotics' direct effect on hypothalamic thermoregulation through dopamine blocking may make it difficult for chronically schizophrenic patients to regulate their body temperature during anesthesia. Thus, patients with chronic schizophrenia benefit most from temperature monitoring and appropriate thermal management. In particular, if there is no response to stress, schizophrenic patients exhibit anomalies in the hypothalamic-pituitary-adrenal and autonomic nerve function. Using antipsychotics lowers the plasma cortisol level. By reducing insulin activity, antipsychotics can cause glucose intolerance. Frequently reported electrocardiographic abnormalities caused by antipsychotic medicines are elongation of the QT and PR (duration of atrial and ventricular depolarization) intervals and T wave changes. Antipsychotic medication users experience torsades de pointes and sudden death 10 to 15 times more frequently than people without such conditions. Additionally, the anticholinergic and noradrenergic effects of antipsychotic medications result in paralytic ileus.
Conclusion:
The anaesthesiologist has a crucial role in preventing pre- and post-operative complications. The anesthesiologist should concentrate on risk management to prevent perioperative mortality, physical morbidity, withdrawal issues, and acute or long-term relapse of psychiatric illness to avoid last-minute surgery cancellation. Selective serotonin reuptake and TCA should be continued throughout the perioperative period to prevent discontinuation syndrome. Careful planning is essential for patients on MAOIs. Opioids like pethidine and indirectly acting sympathomimetics are contraindicated in MAOI patients. Mood stabilizers and antipsychotic drugs should be continued throughout the perioperative period to avoid the risk of relapse.
