The West-Haven criteria calculator evaluates the severity of hepatic encephalopathy based on the user's assessment of consciousness, intellectual function, and behavior. The user selects one of four options that best describes the patient's condition. Each option corresponds to a specific grade of hepatic encephalopathy, ranging from Grade 1 to Grade 4, with escalating severity.

The computation proceeds by using the input selection to identify and assign a severity grade as follows:

1. "Changes in behavior with minimal change in level of consciousness" equates to Grade 1.
2. "Gross disorientation, drowsiness, possibly asterixis, inappropriate behavior" corresponds to Grade 2.
3. "Marked confusion, incoherent speech, sleeping most of the time but arousable to vocal stimuli" is classified as Grade 3.
4. "Comatose, unresponsive to pain; decorticate or decerebrate posturing" is considered Grade 4.

The calculator's logic identifies the selected input option and assigns the appropriate grade, which is then returned as the result. If no valid input is selected, the output will indicate the need for a complete input selection.

The determination process can be structured as follows:

| Assessment Option                                                                                                   | Assigned Grade |
|---------------------------------------------------------------------------------------------------------------------|----------------|
| Changes in behavior with minimal change in level of consciousness                                                   | Grade 1        |
| Gross disorientation, drowsiness, possibly asterixis, inappropriate behavior                                         | Grade 2        |
| Marked confusion, incoherent speech, sleeping most of the time but arousable to vocal stimuli                       | Grade 3        |
| Comatose, unresponsive to pain; decorticate or decerebrate posturing                                                | Grade 4        |

After evaluating the input against these criteria, the calculator outputs the corresponding grade, indicating the severity level of hepatic encephalopathy as assessed by the user's description of symptoms.

The West-Haven Criteria for Hepatic Encephalopathy Severity is a clinical scoring system used to assess the severity of hepatic encephalopathy, a neuropsychiatric syndrome that can occur in patients with liver disease. This calculator is applicable to patients with both acute and chronic liver disease who present with symptoms of hepatic encephalopathy, such as confusion, altered level of consciousness, and neuromuscular dysfunction. 

The clinical utility of the West-Haven Criteria lies in its ability to grade the severity of hepatic encephalopathy on a scale from 0 to 4, with 0 indicating no symptoms and 4 indicating coma. This grading system helps clinicians to monitor disease progression, guide treatment decisions, and assess prognosis. 

There are no specific exclusion criteria for the use of the West-Haven Criteria. However, it should be noted that this scoring system is based on clinical observation and does not take into account laboratory parameters or imaging findings. Therefore, it may not be suitable for patients with atypical presentations or those with other conditions that can mimic the symptoms of hepatic encephalopathy.

West-Haven criteria for hepatic encephalopathy severity