The platform: acquisition hardware, workstations, the INW network and software 6.5.6

Identify which Mac-Lab, CardioLab or ComboLab configuration is in front of you, trace every patient signal from the TRAM or amplifier to the acquisition computer, and know which computer, server and interface holds what before you touch anything.

What this system is, and what it is not

In angio-l1 and angio-l2 you learned the X-ray side of the lab: generator, tube, image chain and positioner. The Mac-Lab and CardioLab family sits next to all that. It is the recording system of the catheterisation or electrophysiology lab: it collects ECG, invasive and non-invasive pressures, SpO2, cardiac output, temperature, EtCO2 and, in EP work, intracardiac signals, displays them, lets the staff log events, measurements and drugs, and turns the case into reports and a stored study. Mac-Lab is the haemodynamic product, CardioLab the EP product, and ComboLab one installation that can run either, but only one of them at a time.

Two points from the manufacturer's statement of intended use shape how you treat it. First, it records and calculates; it does not deliver energy, give drugs or keep anyone alive. Second, it raises no patient alarms and does no arrhythmia detection. That is why the documentation expects a separate defibrillator or ECG monitor whenever a patient needs uninterrupted ECG, and a separate SpO2 display and pacing source where those are critical. For you this means the recorder is never the lab's safety net, and you must never assume that 'the bedside monitor is on the Mac-Lab' is true.

This course follows the INW service manual for software version 6.5.6 (document 2021423-503, revision H). Systems built on the older HP xw8000 and xw8200 computers are covered by the earlier 6.5 manual. Do not mix the two: part numbers, image media and procedures differ.

Three rooms, one system

Think of the installation as three groups of equipment joined by long cables and a network. In the control room stand the acquisition computer, the Integrated Electronics Box (IEB), the UPS, the real-time and review monitors (a third image monitor is optional), local speakers for the QRS tone, a laser printer, keyboard, mouse and barcode scanner, and on EP systems the cardiac stimulator. In the procedure room you find the TRAMNet, meaning a RAC-4A rack holding a TRAM module, the CardioLab II Plus amplifier on EP and Combo systems, one or two remote monitors, remote speakers, the analog output box and, where fitted, the CARTO mapping interface. In the IT room stand the network switch, the Centricity Cardiology INW server and, on many sites, a CVIS server.

Review workstations in offices and nurse's workstations in the lab are clients on the same network. A nurse's workstation joins a running case to chart drugs and supplies; a review workstation opens finished studies in full disclosure to complete reports. When a user says 'the Mac-Lab is broken', your first question is which of these boxes they are sitting at.

The acquisition computer and its boards

The 6.5.6 manual covers two HP workstation platforms for acquisition: the z600 and the xw8400. Both carry the same functional board set, but in different slots, so the slot map in the manual matters when you reseat or replace a card. The primary hard disk is split into C:, the application partition, and D:, the data partition. A second hard disk, G:, is the local backup drive: the weekly database maintenance writes its backup there, and the recovery procedure uses it to bring the system back. A DVD-RAM drive writes studies to removable media; on the xw8400 a magneto-optical drive may be fitted instead or as well. Which drive receives studies is set by the file paths in the application's system settings, not by the hardware.

The cards are what make this computer a medical recorder rather than an office PC. The video board drives the real-time and review monitors (and the optional third): a Matrox Parhelia on the xw8400, a Matrox M9140 quad board on the z600. The TRAMNet-to-Ethernet adapter talks to the TRAM in the RAC-4A. The PCI Communication board carries the fibre-optic link to the CardioLab amplifier, the analog and digital I/O to the IEB and the switching signal for the remote monitor. A dual network card provides the hospital network connection and, on the z600, the serial port for ablation devices. An optional Matrox Odyssey board captures video from the X-ray system or another imaging source for the CardioImage and image capture options.

IEB, UPS and power

The IEB is the power and signal hub of the control room. Inside are a video multiplexer board that buffers and distributes the computer's video outputs to local and remote monitors, an I/O board that passes TRAM data, analog inputs from other equipment and analog outputs to the stimulator and analog output box, a small power supply for the video board and the RAC-4A, and a 2.0 kVA medical-grade isolation transformer built to IEC 60601-1. The transformer is wired in parallel for 100 and 120 V systems and in series for 240 V, and the manual warns you to restore the connections correctly if you ever disconnect it. The IEB has two switches that both have to be on: the main power switch on the front and a thermal overcurrent breaker on the back.

The UPS is external to the IEB and backs up the computer only. If mains fails, the monitors, the IEB peripherals and the amplifier go dark while the computer keeps running long enough to protect the open study and the database. Users often expect the whole lab to stay up on the UPS; it is worth explaining this at handover. The 6.5.6 parts list shows 1500 VA units in 100, 120 and 230 V versions supplied as replacement kits.

Acquisition hardware in the procedure room

The TRAMNet is the patient interface of Mac-Lab. The TRAM module plugs into the RAC-4A, which takes its supply from the IEB, and the patient cables land on colour-coded inputs: green for ECG (5 or 10 lead), red for the three invasive pressures, black for NIBP, blue for SpO2 and brown for thermodilution cardiac output. The manual lists the supported TRAM families (200SL, 400/450SL, 451 variants and 600/650SL) and the TRAM software revisions it accepts; record both, because a TRAM borrowed from a monitoring system may carry a revision the recorder does not support. The SpO2 technology differs between TRAM variants (the manual names Ohmeda, Nellcor and Masimo versions of the 451), so check the sensor and adapter cable against the TRAM fitted, not against the Mac-Lab.

The CardioLab II Plus amplifier is the EP front end. Versions exist with 32, 64, 96 and 128 channels. It accepts a 10-lead ECG cable, four pressure transducers of the standard 5 µV/V/mmHg sensitivity, a stimulator input, an auxiliary input and up to three or seven 32-pole catheter input modules depending on size. It sends its data to the computer over a duplex fibre-optic cable, and three LEDs on the front tell you the state of that link: XMT should be lit whenever the amplifier is on, RCV CMD flickers when commands arrive, and RCV ERR means the amplifier is not receiving valid data, often a fibre problem. The rear carries an equipotential terminal.

Every input on the TRAM and the amplifier is a patient connection, and on EP and haemodynamic work much of it is intracardiac. Treat the whole front end as type CF (cardiac floating) territory and read the applied-part symbol on each unit's label: lead electrodes must not touch other conductive parts, only equipment certified to IEC 60601-1 may be connected to the amplifier, and the manual tells users to disconnect intracardiac catheters before internal defibrillation to protect the amplifier. The analog output box takes heart-rate and pressure signals from the TRAMNet or, through the IEB, from the amplifier and distributes them to other equipment, typically for synchronisation.

Network, servers, interfaces and software

A standalone system keeps its studies locally. On a network, the Centricity Cardiology INW server is the repository: acquisition systems archive finished studies to it, and every acquisition and review system can open them. In the standard INW setup the server is also the Windows domain controller and DNS server for the lab systems, and they take their time from it; you will see in lessons 2 and 4 why that matters. The 6.5.6 manual covers G4, G5 and G6 servers, each with a mirrored RAID 1 system drive, a RAID 5 data drive and a tape drive for backup. Server hardware is ordinary IT equipment and must stay outside the patient environment, which the manual defines as extending 1.83 m around the patient support and 2.5 m above the floor.

The CVIS server, where present, provides central lists of staff and supplies, scheduling, patient demographics, inventory and statistics. The interfaces between the boxes use standard protocols you met in pacs-dicom: DICOM modality worklist and MPPS between Mac-Lab and the CVIS, HL7 export of results to the CVIS, and a DICOM link where the X-ray system (for example a GE Innova) asks the Mac-Lab for patient and study data, so on that link the connections run from the X-ray system to the recorder. Remote service runs through InSite ExC or a VPN.

The software stack of 6.5.6 is old and you must know its exact parts. Acquisition and review workstations run Windows XP Professional SP3 with SQL Server 2000 Desktop Edition and Office 2007; the INW server runs Windows Server 2003 SP2 with SQL Server 2000 Standard. Users log in through a custom shell, not the normal Windows desktop. The manual also notes that z600 computers and G6 servers may arrive with a newer 6.8.1 image and must be reimaged to run 6.5.6. Finally, find the serial labels before anything else: on top of the computer, on the back of the IEB, on the right side of the RAC-4A, and on the backs of the TRAM and the amplifier.

On-site checklist

• System type recorded: Mac-Lab, CardioLab or ComboLab; standalone or INW network
• Computer model (z600 or xw8400) and serial label on top of the computer recorded
• IEB voltage version, RAC-4A, TRAM model and software revision, amplifier channel count and serials recorded
• Application version confirmed as 6.5.6; operating system and database versions noted
• Optional boards noted: image capture, third monitor, ablation serial, CARTO
• Server generation, RAID layout and tape drive noted on networked sites
• Interfaces listed: CVIS, X-ray DICOM, HL7, DASH/Solar, remote service
• Lab staff aware that the recorder raises no patient alarms and that the UPS covers only the computer

Check yourself