PT and PTT Photometric clot detection assesses the coagulation endpoint by measuring the change in optical density of a plasma specimen. Light will be scattered by fibrin strands forming when fibrinogen converts to fibrin. Light passed through a plasma sample is monitored by a photosensitive detector. As the sample becomes more optically dense (caused by light scattering from an increasing number of fibrin strands), the amount of light falling on the detector is decreased. This change in light level alters the electrical signal output from the detector. Whole blood Blue top tubes which contain 3.8% liquid Sodium Citrate are to be used for all PT's and PTT'S. Minimum acceptable total volumes - 5 cc tubes must contain at least 4.5 cc - 3 cc tubes must contain at least 2.7 cc 2.2 Specimen handling Sample is grossly hemolyzed There is insufficient sample Specimen is clotted There is greater than a four-hour span between collection and delivery of specimen to the laboratory Contact the appropriate area and request another sample. Record the accession number, the patient's name and unit location, the contact person and the time in the coagulation unsatisfactory log book. Thromboplastin C-Plus Dade Reconstitued with 20 mL of deionized water using a 20 mL Class A volumetric pipette. If refrigerated, the reagent is stable for three days. Refrigerate - stable for three days Actin Dade Once opened, Actin is stable and can be used until controls are out of range. Calcium Chloride Dade Once opened, Calcium Chloride is stable until visible microbial contamination is seen. Deionized Water MLA Electra 1000C Start-up 6:00 A.M. (or beginning at each shift) Make sure power switch is "on". This is on the front of the unit below the right side of the keyboard. If the unit is already on, be sure that the monitor displays the "Main Menu". To take the monitor back to "Main Menu" press the "Esc" (escape) key until you get to the "Main Menu". Select (2) "Consumable." Select (1) "Edit" from the bottom of the screen. Using the directional arrow key ( ) and 0, move the cursor to the line where changes are to be made and press the "Enter" key. Follow the instructions on the prompt lines to make changes. Put reservoir cups in wells 1, 2, and 3. Load a blue heat exchanger in slots A and C and a red heat exchanger in slot B. Load pump tubing by opening each pump lever (PT tubing is change once a week and PTT tubing once a week). Slide each connector into the posts, making sure that the colored mark faces up. The shorter piece of tubing connects to the heat exchanger Close each pump lever. Be certain heat exchangers are fully lowered into the heat exchanger slots and that the tubing is not pinched. Add reagents to the proper reservoirs: Calcium Chloride - Reservoir #1 Thromboplastin - Reservoir #2 Actin - Reservoir #3 Add stir bars: Calcium Chloride - White bar Thromboplastin - Red bar Actin - Blue bar To prime pumps: Go to "Main Menu" select (3) "Pumps." Remove heat exchanges from wells. Hold heat exchanger over the proper cup and select the number beside the pump to be primed. Do this for each pump. Return heat exchangers to proper well positions. Go to "consumables" and enter necessary changes. Fill the rinse container with deionized water. This is to be checked daily. Reset "Wash Status" to l000 mL under "consumables". Fill the hopper with MLA clear, single-well cuvettes to the fill line. (This is approximately 150 cuvettes.) Reset "Hopper Status" to 150 under "Consumables." Reservoir Assemblies: - Blue - 0.05 mL Delivery of Heated Reagent - Red - 0.1 mL Delivery of Heated Reagent - Reservoir Cups - Blue Heat Exchanger - Red Heat Exchanger Clear, Single-Welled Cuvettes Magnetic Stirrers Thermal Printer Paper Dispo Bin Volumetric Pipette, 1 mL, Class A Volumetric Pipette, 20 mL, Certified Class A Blue Top Vacutainers - Citrated Centrifuge Wooden Applicators Rinse Solution Container Waste Container Citrol Level I Dade reconstituted with 1 mL of deionized water using a 1 mL class A volumetric pipette. Level I is stable for eight hours Citrol Level II Dade reconstituted with 1 mL of deionized water using a 1 mL class A volumetric pipette. Level II is stable for six hours. Both Level I and Level 11 controls are to be run at the beginning of each 8 hour shift on each Electra. Each control must be verified as within range before any results may be reported. After initial startup, run Level I only every two hours. The Confidence test is done at the beginning of each shift. The confidence test is an internal instrument monitor of the optical detection system and instrument timing. From "Main Menu" select "Run." From "Run" select "Confidence Test." Log results in QC book. From "Main Menu" select "Patient List". Select "Batch Entry" from "Patient List Menu". Under Patient ID column enter: "l " For Level I control "2" For Level 11 control Press enter after each ID entry. Select PT and PTT for each control. Place controls in the plasma reagent rack (PRR) on the right side of the sample racks in the holes marked Levels I and 11. Run test. Result QC in Sunquest using C-Coag I and C-Coag 11 for level I and 11 in cups 1601 and 1602. Plot QC results on the graphs in the QC book. Temperatures of the testing area, reagent cooling area and the plasma reagent rack on the MLA1000 are to be taken at the beginning of each shift and logged in the book. From "Main Menu" select "Run." Temperatures of the testing area and reagent area will be displayed in the upper right hand corner. While still in "Main Menu" with "Run" highlighted push escape to bring up the plasma reagent rack temperature. Log results in the QC book. When Quality Control is out of range Repeat on same vial of control. Repeat on new vial of control. Repeat control with fresh reagent. If still out of range, discontinue use of instrument and notify supervisor. Record corrective action for the Quality Control in the corrective action log. Grossly lipemic specimens may show "NCD" (no clot detected). The cuvettes in the dispo bin may be checked for presence of a clot. If clotted, see the procedure for using the fibrometer. All tubes are checked for clots using wooden applicator sticks. Samples are centrifuged with at 2000 RPM's for 10 minutes. At "Main Menu" select (4) "Patient List." Select (6) "Batch Entry." When window appears select (3) PT/PTT Wand sample ID (barcode label on tube) or manually enter ID If first run of the shift, a fibrinogen maybe added to the first sample to maintain an active work list. To add the fibrinogen: After entering the first patient ID, press "Escape." Select (4) "Done." At the bottom of the screen options will appear. Select (1) "Edit." At the next set of options select (1) "Add." Enter ID of sample to which the fibrinogen is being added. Press enter "Sample Rack" window will appear. Select (1) "Rack A." "Rack A Position" window will appear. Enter Position I. "Test Mode" Window will appear. Select (2) "Fibrinogen" - This adds the fibrinogen. Press "Esc" twice. From options at the bottom of the screen. Select (5) "Done." This will take you back to the Master Patient List. To continue adding samples to the current worklist select (7) "Batch". This will return you to the "Test Mode" window. Choose (3)"PT/PTT" and wand bar codes of remaining samples. Press "Esc" when all samples have been wanded. "Test Mode" window appears, select (4) "Done." From the options at the bottom of the screen select (8) "DoneAt "Patient List" Menu press "Esc." At "Main Menu" select (5) "Run." At "Run Menu" select (3) "Test Run." The printout will display the patient ID, (acc #), the sample location in the rack, test ordered and sample results. Introducing STAT specimens during a patient run The stat (K) rack can only be accessed from the run screen while other Protime and PTTs are running. From the "Run Screen," stats is number four on the prompt line at the bottom of the screen. If you are on the "Patient List Screen," (the words "Patient List" will show at the top of the screen) access the "Run Screen" by pressing escape. Select #4 "Stat" from the prompt and the "stat list" will appear. Select #1 "Add" from the prompt line. Wand in the patient ID. The "K Sample Rack" box will pop up. Press enter. The "K Rack Position" box will pop up. Select the rack position in which the tube will be placed. Press enter. The "Test Mode" box will pop up. Select the tests to be run. Press enter. Repeat steps 3-5 above (Select #4 "Stat" from the prompt and the "stat list" will appear. Select #1 "Add" from the prompt line. Wand in the patient ID. The "K Sample Rack" box will pop up.) until all stats to be run have been entered. Press escape. Press escape again. Choose #6 "Exit" from the prompt line. Press #1 "To Add Stat" from the pop up box. The sampler will then access the stat tubes on the next set of four cuvettes it runs. Results will be printed in the order in which the specimens were picked up. Cup for OEM or OEO release being with 1100. Specimens run in the "K" rack do not show up on the patient list. Once the "Run List" is done, "K" rack specimens only will show from the "Stat List." Result stats Using Sunquest program OFC (Online File Clean-up) clear the patient list at the beginning of the 7 AM shift using device CMLA2 or CMLA3, clearing cups 1-1200. After any result prints go to Sunquest Function OEM (Online Result Entry) method code CMLA2, CMLA3 or CMLA4 and enter cup number corresponding to printout. "A" rack, space 1 will be cup 101, "B" rack = 2, "C" = 3, "D" = 4, "E" = 5, "F" = 6, "G" = 7, "H = 8, "J" = 1 0, and "K" = 1 1. The patient demographics plus results will appear on the screen. Accept, Modify, Display previous or Reject results. To result controls, accession # will be C-COAGI for normal control an C-COAGII for abnormal control. Print incomplete log using Function LO, use printer 311 or 313, Option 1, start date today "T," return, cut-off date, return, cut-off time, return, unreceived specimens?, no, preliminary results, no, hospital id: PUH, CHP, FALK, <CR>, accept, worksheet, CG20 or CPT or CPTT, all lab locations then accept. Review those samples with receive times but still not resulted, making sure they are in the lab being processed or assayed. Investigate any missing specimens. Adult 12.8 +/- 1.6 sec Pediatric 12.8 +/- 1.5 sec Newborn 14.5 +/- 1.0 sec Adult 25 +/- 5.0 sec Pediatric 25 +/- 5.0 sec Newborn 41 +/- 21.0 sec Samples are run using single sample testing. Set test parameters to half volume. Samples should be repeated in the following cases: - Protime: Values > 46.0 seconds - APTT: Values > 100.0 seconds It is not necessary to repeat values that fail delta limits. Call PT deltas if change is greater than 10 seconds. - Call PT results > 25.0 seconds - Call INR results > 4.2 seconds Call PTT deltas if change is greater than 30 seconds. Call PTT results > 75.0 seconds Report PTs greater than 46.0 seconds as > 46.0. Report APTTs greater than 100.0 seconds as > 100.0 Operator's Training Manual Electra 1000C Automatic Coagulation Timer, Oct 1991. Dade Reagent inserts, Baxter Diagnostics Inc., 1992. Clinical Diagnosis, Henry, 18th Edition 734-757 1991