Postoperative depression is a perioperative psychological complication that severely affects patient recovery and quality of life. In extreme cases, it may lead to suicidal behavior. Postoperative depression can be seen in various surgical operations .

High rates of anxiety and depression have been reported in cohorts of patients with IIH, though it is not clear whether there is any direct relationship. Worse outcomes in terms of disability level and symptom resolution have been observed in IIH patients who have a known co-existing psychiatric illness compared to those who do not .

Postoperative depression is a perioperative psychological complication that severely affects patient recovery and quality of life. In extreme cases, it may lead to suicidal behavior. Postoperative depression can be seen in various surgical operations.

Idiopathic intracranial hypertension (IIH) is the most common cause of papilledema and is typically seen in young women with elevated body mass index. The prevalence of IIH has been increasing in recent years, in parallel with climbing rates of obesity .

High rates of anxiety and depression have been reported in cohorts of patients with IIH, though it is not clear whether there is any direct relationship. Worse outcomes in terms of disability level and symptom resolution have been observed in IIH patients who have a known co-existing psychiatric illness compared to those who do not .

The use of lumbo-peritoneal (LP) shunts has been well documented as a treatment modality for patients with idiopathic intracranial hypertension (IIH). There are a number of advantages to LP shunts when compared with other treatment modalities for IIH, such as stereotactic ventriculo-peritoneal shunts (VP) and optic nerve sheath fenestrations (ONSF). LP shunts avoid intracranial risks, such as cerebral hemorrhage, seizures, and shunt malposition.

Over the past decade, it has been provoked a single administration of ketamine elicits fast (in as little as half an hour) and sustained antidepressant effects both in human and animal models of depression. There are some potential mechanisms of antidepressant actions of ketamine. MK-801, a noncompetitive NMDA receptor antagonist, produced antidepressant-like actions in the animal model of depression . Ketamine can also increase hippocampal brain-derived neurotrophic factor levels, which may be important for producing a rapid onset of antidepressant action .A recent study found ketamine could quickly elevate mood by blocking NMDAR receptor-dependent bursting activity of the lateral habenula neurons to disinhibit downstream monoaminergic reward centers and provide a framework for developing new rapid-acting antidepressants .

Accordingly, we hypothesized that intraoperative ketamine can reduce the post operative depressive symptoms after theco-peritoneal shunt insertion.

Inclusion Criteria:

• patients of both sex
• with an age range from 20 to 44 years old
• having moderate to severe depressive symptoms
• an expected hospital stay of no less than 7 days

Exclusion Criteria:

• history of epilepsy
• major depressive disorder patients
• drug abuse
• history of allergy to the research drug
• heart rate > 120 beats per minute
• systolic blood pressure > 180 mmHg
• heart failure
• renal or liver dysfunction
• patients who cannot cooperate to complete psychiatric assessments
• pregnant or breast-feeding women
• patients who refuse to sign informed consent.