P1153 'HL7 Domain Analysis Model: Intra-Procedure Anesthesia, R1' provides a general model for records of intra-procedural anesthesia. This was based on a content analysis of US and international guidelines, around 30 anesthesia records, from different countries, and contributions from an international group of domain experts. 

The current project (PSS-1936), is a FHIR Implementation Guide for the Intra-procedural Anesthesia Record for use, primarily, by developers and researchers but also, clinicians, vendors and payors. The IG will provide guidance on how the content of conventional anesthesia records, as described in P1153,  may be represented using FHIR resources, to provide a persistent electronic clinical document.

The electronic anesthesia record is typically produced by an Anesthesia Information Management System (AIMS), or AIMS component, which is capable of exchanging data electronically with other systems such as the EHR, Clinical Laboratories and patient-connected devices. Where information is required to be entered manually the AIMS is assumed to provide a user interface that facilitates the process, for example, by implementing context dependent, structured entries, including relevant value sets and time-stamping.

This  FHIR implementation guide is intended for use by multiple stakeholders who implement or use electronic anesthesia records,  particularly, developers and researchers. The IG provides guidance on how the anesthesia record may be represented, using FHIR resources, to provide a persistent electronic clinical document. It will fully reference the ISO/IEEE 11073 family of base standards for Health informatics and medical / health device communication, including the IEEE 11073 Service-oriented Device Connectivity (SDC) standards and the related Gemini SES MDI program's Service-oriented Device Point-of-care Interoperability (SDPi) profiles that include an anesthesia workstation specialization. 

The IG describes generic procedures that may be included in or used to extend, more specialised clinical procedures that are documented in the record. For both types, appropriate value sets will be defined. Modern anesthesia is reliant on patient-connected devices e.g. ventilators/anesthetic machines, syringe pumps and physiological monitors so accurate and detailed recording of data coming from these devices, including their operational settings, is a high priority.  In this area, the IG will make detailed reference to the FHIR 'Point-of-Care Device Implementation Guide'.

Much of the semantic content of the record is represented with terms from controlled nomenclatures, organized into value sets. Relevant vocabularies used in this project are IEEE 11073, SNOMED CT and LOINC. In 2003 the Anesthetic Patient Safety Foundation (APSF) established a Data Dictionary Task Force (DDTF) which later became known as the International Organization for Terminology in Anesthesia (IOTA). The aim was to create a vocabulary for the domain of anesthesia. The current term set contains just under 5,000 concepts. The terms are now maintained by the SNOMED CT Anesthesia Clinical Reference Group (CRG).

Scope of IG

In Scope:

• All information pertinent to the intra-procedural phase of anesthesia.

Examples include:

1. Administrative and contextual information: for example, details of the patient and care-providers, and the main procedure(s) that are the focus of the current anesthesia episode.
2. Checklists and notes of discussions during timeouts: for example the WHO Surgical Safety Checklist (that includes timeouts) and ASA Checklist
3. Milestone events: for example ‘Patient in care of anesthesiologist’, ‘Induction of General Anesthesia’, ‘Start of Surgery’ etc.
4. Events relevant to anesthesia and the clinical status of the patient during the procedure (including untoward events and critical incidents).
5. Anesthesia procedures, for example: airway management, respiratory support, administration of drugs (including volatile agents), fluids and gases, insertion of venous and arterial lines, regional anesthesia etc.
6. Lab results
7. Physiological parameters / vital signs, for example: heart rate, respiration rate, blood pressures, oxygen saturation and derived measures such as the bispectral index.
8. Operational settings of patient connected devices

As an example of the method(s) by which information is acquired, categories 1 and 6, above may be accessed electronically from existing sources and/or manually entered, 2 – 5, mainly by manual entry, 7 mainly electronically but occasionally, manually and 8, mainly manually but increasingly, electronically.

Regarding, 7 and 8, the communication of data to and from Point of Care Devices (PoCD) has been the focus of many years of effort exemplified by the ISO/IEEE 11073 Healthcare Device Communication Standards and the BICEPS, IHE/SDPi and Gemini projects. Specifically relevant to this project is the ‘HL7 FHIR Point-of-Care Device Implementation Guide’ which ‘… defines the use of FHIR resources to convey measurements and supporting data from acute care point-of-care medical devices (PoCD), intended for use by qualified professionals, to receiving systems for electronic medical records, clinical decision support, and medical data archiving for aggregate quality measurement and research purposes. It adds “deep metadata for device observations” (https://build.fhir.org/ig/HL7/uv-pocd/). These initiatives provide levels of detail and description that, ideally, should form an important part of the electronic anesthesia record but which are not in the independent scope of this project. It is intended that PoCD data should be represented for the purposes of the human readable-record, in a relatively simple way, whilst preserving the option to include, or reference, the “deep metadata” where this is available. This allows flexibility regarding the sources of device-related data and the ways those data are presented (for example manual entries, HL7 V2 messages).

Out of scope:

• Independent modelling of PoCD data that has already been done elsewhere (see above). 
• Pre-operative assessment
• Post-operative care

Stakeholders 

• Developers: The IG will provide a detailed practical scheme for implementing a comprehensive electronic anesthesia record based on international standards. 
• Researchers: Records created using this IG will feature consistent representation of objects, consistent semantics and high granularity, especially in regard to data acquired from devices.
• Clinicians: The IG will facilitate the production of the anesthesia records for clinical review and governance and to satisfy the requirement for medico-legal documentation
• Payors: The IG will enable the extraction of detailed information on personnel, procedures, timings and the use of physical resources