Picture this: You are a healthcare professional responsible for managing patient data and ensuring seamless communication between different healthcare systems…

How do you navigate the complexities of exchanging vital patient information across disparate systems?

Enter HL7 (Health Level Seven) messages, the backbone of healthcare data exchange that allows healthcare providers to communicate effectively.

In this article, we will dive deep into the world of HL7 segments, their structure, and their practical application in healthcare data exchange, as well as help you understand where our team of expert HL7 consultants can come in to help. Let’s dive in!

Short Summary

  • HL7 segments are the building blocks of HL7 messages, facilitating data transfer and integration between healthcare providers.
  • Each segment comprises fields, components, and sub-components divided by delimiter characters to organize data for effective communication.
  • Vendor variations in segment structure require specialized tools for accurate interpretation and message customization via Z-segments to improve patient care outcomes.

What are HL7 Segments?

HL7 (Health Level 7) segments are standardized data elements within HL7 messages for exchanging healthcare information. These segments organize and structure data in a message, representing specific types of information such as patient demographics, clinical observations, and administrative details, allowing for interoperability and data exchange in healthcare systems.

Understanding the Main Capabilities of HL7 Segments

In healthcare data exchange, HL7 messages play a crucial role in facilitating the transfer, integration, sharing, and retrieval of clinical and administrative data between various healthcare providers. An HL7 message is a hierarchical structure associated with a trigger event, such as patient admission.

At the heart of these messages are HL7 segments – structured sets of predefined components that form the foundation of an HL7 message. For example, a sample message could include segments like MSH, NK1, PV1, and PID to facilitate more efficient messaging and offer a human-readable summary of each message.

An HL7 message comprises one or more segments, each dedicated to capturing specific categories of data, such as patient visit data or patient identification. These segments are further divided into elements, which can be a primitive data type or comprised of multiple other composites.

And, with over 120 distinct HL7 segments available for use, these are the building blocks allowing healthcare systems to communicate and share crucial patient information efficiently.

Purpose of Segments

Segments in HL7 messages serve as the foundation for structuring and classifying data within the message. But how do we differentiate between these segments? Segment IDs come to the rescue! These unique three-character codes help identify and differentiate each segment in HL7, ensuring accurate interpretation of the given message content.

For instance, the OBX segment conveys observation data in HL7 messages. Correctly identifying and interpreting segments like OBX plays a vital role in ensuring healthcare providers have access to accurate and timely information about patients and their healthcare needs.

Segment Structure

A typical HL7 segment is a well-organized structure of fields, components, and sub-components. These components come together to create a coherent structure that allows for efficient healthcare data exchange.

Common data types utilized in HL7 messages include XTN (Extended Telecommunication Number), IS (Coded value for user-defined tables), and CE (Coded Element), which are examples of primitive data types.

Understanding the structure of HL7 segments and their various data types is crucial for accurate interpretation and efficient handling of healthcare data. However, this process can be challenging due to vendor variations and the requirement for specific tools for parsing HL7 messages.

Navigating Common HL7 Segments

In healthcare data exchange, specific HL7 segments are more commonly used than others. For example, message formats used most frequently in HL7 include ACK (Acknowledgment), ADT (Admission, Discharge, and Transfer), ORM (Order Message), and DFT (Detailed Financial Transaction).

These formats allow for the efficient sharing of essential patient demographic information and healthcare data across systems and make it easier for organizations to register patient data in specific segments.

Each segment is crucial in organizing and conveying vital patient information within an HL7 message. To better understand how these segments work together, let’s dive deeper into three significant segments: MSH (Message Header), PID (Patient Identification), and PV1 (Patient Visit).

MSH (Message Header)

The MSH segment is the first segment in any HL7 message, containing essential information related to the sender, receiver, and message type. It serves as the starting point of any HL7 message and plays a vital role in ensuring the message is processed and interpreted accurately by the receiver.

In the MSH segment, you will find crucial data such as the message control ID, which helps uniquely identify the message, and the event type, which indicates the trigger event associated with the message. By providing a clear and accurate snapshot of the sender, receiver, and message type, the MSH segment lays the groundwork for the efficient exchange of healthcare data in HL7 messages.

PID (Patient Identification)

The PID segment is the heart of patient information within an HL7 message, containing patient demographics and identification data. This vital segment ensures that healthcare providers have access to accurate and up-to-date information about the patient, which is crucial in facilitating more informed decision-making and better patient care.

In the PID segment, you will find key data elements such as the patient ID, which serves as a unique identifier for the patient, as well as the patient’s name, address, and other demographic information. By providing a comprehensive view of the patient’s personal and demographic information, the PID segment allows healthcare providers to better understand their patients and deliver personalized care.

PV1 (Patient Visit)

The PV1 segment focuses on the details of a patient’s hospital stay. This segment provides information related to the patient’s admission, length of the patient’s hospital stay, attending physician, location assigned, referring doctor, and other visit-related data.

In the PV1 segment, you will find valuable information, such as the attending physician’s name, which can help healthcare providers coordinate care and ensure timely follow-up. By providing a clear picture of the patient’s visit, the PV1 segment enables healthcare providers to better understand the patient’s healthcare journey and make informed decisions about their care, including when to register patients for follow-up appointments.

Understanding HL7 Segment Delimiters

In order to efficiently communicate the various components of an HL7 segment, delimiter characters are used to separate fields, components, and sub-components within the segment. These special characters play a crucial role in ensuring that the message structure remains intact and is easily interpretable by the receiver.

Understanding the function of delimiter characters is essential for accurately interpreting and working with HL7 messages. In the following sections, we will explore the default delimiter characters used in HL7 messages, as well as the possibility of using custom delimiter characters.

Default Delimiter Characters

The default delimiter characters used in HL7 messages serve specific functions, helping maintain the message’s structure and organization. These characters include the escape character (\) for beginning and ending a message, the vertical bar (|) for field separation, the caret (^) for component separation, and the tilde character (~) for separating repeating fields.

By understanding the roles of these delimiter characters, you can better comprehend the structure and organization of HL7 messages and efficiently work with healthcare data.

Custom Delimiter Characters

While the default delimiter characters are widely used in HL7 messages, there may be scenarios where custom delimiter characters are needed to better suit specific requirements or preferences. In such cases, custom delimiter characters can be defined within the MSH segment of the message.

By specifying custom delimiter characters in the MSH-2 field of the MSH segment, you can tailor the delimiter characters to your needs and ensure a more seamless exchange of healthcare data between disparate systems. Custom delimiter characters provide flexibility and customization options in HL7 messaging, catering to the unique needs of various healthcare providers.

Working with HL7 Z-Segments

In addition to the standard HL7 segments, there are also Z-segments, which are custom message segments not formally included in the HL7 standard. These specialized segments allow for the incorporation of custom data and information that may be specific to a particular healthcare organization or system.

Let’s explore the purpose of Z-segments and how they can be used to extend the standard HL7 message structure, as well as how to create custom Z-segments for your healthcare data exchange needs.

Purpose of Z-Segments

Z-segments serve as a means to include custom or local data that is not part of the HL7 standard, allowing for greater flexibility and customization in HL7 messaging. By incorporating Z-segments, healthcare providers can include specialized clinical or patient information that may not be available in the standard HL7 message structure.

The use of Z-segments not only allows healthcare organizations to tailor the message content to their specific needs, but also helps in providing more detailed information about patients and their healthcare events. This, in turn, can enhance the quality of care and improve patient outcomes.

Creating Z-Segments

Creating a custom Z-segment involves defining message segments that are not part of the HL7 standard, with segment IDs beginning with the letter Z. These segments can be inserted anywhere in the message and typically contain specialized clinical or patient information.

When incorporating custom Z-segments in an HL7 message, it is important to ensure that they are placed appropriately within the message structure, typically after the MSH segment and before the initial segment of the message body.

By creating and using custom Z-segments, healthcare providers can enhance the depth and breadth of information available in their HL7 messages, ultimately leading to better-informed decision-making and improved patient care.

Main Challenges in Interpreting HL7 Segments

Interpreting and working with HL7 segments can be a complex and challenging task, especially due to the existence of vendor-specific variations and the intricacies of segment structure.

As HL7 messages are used to exchange vital patient information across healthcare systems, it is essential for healthcare professionals to accurately interpret and process these messages to ensure optimal patient care and coordination.

In this section, we will discuss some common challenges faced in interpreting HL7 segments, including vendor variations and the need for specific tools and solutions to efficiently parse and interpret HL7 messages.

Vendor Variations

One major challenge in interpreting and working with HL7 segments is the existence of vendor variations, which can affect the message structure, segment order, and segment content. These variations can complicate the interpretation of HL7 messages and make it difficult for healthcare professionals to accurately process and utilize the information contained within the message.

Different healthcare systems and vendors may have variations in their HL7 messages, which can affect the interpretation of segments and ultimately impact patient care. Healthcare professionals need to be aware of these variations and take them into account when working with HL7 messages to ensure accurate interpretation and data exchange.

Tools for Parsing HL7 Messages

To overcome the challenges associated with interpreting HL7 segments, various tools and solutions have been developed to aid in parsing and interpreting HL7 messages more efficiently. These tools, such as HL7 Message Parser, ParseHog HL7 Parser, HL7.cc tools, HL7 Inspector Neo, 7Edit, and the Python-HL7 Library, offer a range of features and capabilities to help healthcare professionals accurately process and understand the information contained within HL7 messages.

While these tools can significantly aid in interpreting and working with HL7 segments, it is important to note that they may have limitations, such as restricted support for vendor variations and the absence of support for certain message types. Leveraging these tools can greatly enhance the efficiency and accuracy of interpreting HL7 messages, ultimately improving patient care and healthcare data exchange.

Practical Examples of HL7 Segment Usage

After exploring the intricacies of HL7 segments, it’s time to see them in action! In this section, we will provide real-life examples of HL7 messages with various segments, demonstrating their practical application in healthcare data exchange.

These examples will help you better understand how different segments come together to form a coherent and meaningful message that enables efficient communication between healthcare providers.

Let’s take a closer look at two practical examples of HL7 segment usage: an ADT (Admission, Discharge, and Transfer) message and an ORM (Order Message) message, both of which are commonly used in healthcare data exchange.

ADT Message Example

An ADT message serves to notify physicians and care management teams about a patient’s condition, facilitating follow-up and promoting provider communication. It contains vital patient demographic information, such as contact information, address, medical record number, insurance, and next of kin, as well as visit information, such as length of stay, attending physician, and reasons for admission or discharge.

In our ADT message example, we see the use of key segments like MSH (Message Header), PID (Patient Identification), and PV1 (Patient Visit), which come together to form a comprehensive and informative message that can greatly impact point-of-care decisions and patient outcomes.

ORM Message Example

An ORM message is used to facilitate the transmission of information pertaining to a requested service, such as an order for a medication prescription or a diagnostic test request. Changes to an order, such as additions, cancellations, modifications, and discontinuation, require sending an ORM HL7 message. This helps process the new change quickly and efficiently.

In our ORM message example, we highlight the use of specific segments such as ORC (Order Common) and OBR (Observation Request), which provide details regarding the order, including the order number, ordering provider, order date, order status, and order items.

By understanding the structure and function of these segments, healthcare providers can ensure accurate and timely processing of patient orders, ultimately leading to better patient care.

How Can We Help?

Whether you need help understanding the role of HL7 segments in facilitating more efficient data exchange, additional support outlining segments and components for new HL7 messages, or an extra hand using HL7 standards to facilitate a human-readable summary of each message, Surety Systems can help.

Our team of senior-level HL7 consultants has the skills, experience, and technical know-how to handle all your project needs, regardless of the complexity of your organizational structure or the nature of your healthcare integration needs.

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Interested in learning more about HL7 or where our healthcare integration consultants can fit in your organization? Contact us today to get started!