Lakshmy Ramakrishnan Professor Cardiac Biochemistry AIIMS

1. CEUTEH‘16
Ms.Lakshmy Ramakrishnan
 B.Sc (Chemistry,botany, zoology),M.Sc
(Biochemistry) PhD (Biochemistry)
 Professor, Cardiac Biochemistry , AIIMS
 She has been a principle investigator for many
projects for which she had received extramural
research funding from ICMR, DST, DBT
 She is an author of more than 150 publications,
Both national and international
 Worked as Research Associate in a National
multicentric urban hospital

2. PNEUMATIC TUBE SYSTEM
Lakshmy Ramakrishnan
Professor
Cardiac Biochemistry

3. What is PTS?
• Network of tubes through which
materials are sent using cylindrical
containers using compressed air or
vacuum

4. Why PTS
• Modern health care-more care at less cost
• Reduce length of hospital stay and facilitate
early discharge
• Speedy diagnosis is of utmost importance
• PTS –faster delivery of material and therefore
reduce TAT

5. History
• Use dates back to early 19th century
• In postal department and departmental stores
• move papers
• Advent of email and fax
• Originally the landing of materials used to be
hard
• In late 1980s technology developed to control
airflow - slow down the containers for soft
landing

6. Simple PTS

7. Types of PTS
Point to point
– One way system A----->B
– Two way system-Transfer of carriers occurs between two
stations A<------>B
Semi-automatic
Main station is the transfer hub
Receives and delivers to multiple remote stations
The remote stations can only send directly to main
station
Fully automatic
Allows any station to send and receive from any other
station

8. Point to point PTS

9. Advanced pneumatic tube station

10. Application in hospitals
• Sending blood samples to laboratory
• Blood samples/bags to blood bank
• Pathology specimens
• Medicine from pharmacy
• X-rays
• Medical Reports
• Small surgical and medical equipments

11. Components of multipoint PTS
Hospitals pneumatic tube system consists of:
• Blower-Source of air for motion of carrier. create difference
in air pressure between two ends of the system sucks
carriers, allows carriers to move
• Tubing- Through which carrier moves. PVC/Steel-110mm or
305 mm
• Diverters- required at branch point for connecting different
system areas- can be 2, 3 or 4 way. One pipe going into it
and 3 pipes going out

12. Components of PTS
• Stations also called sample distribution
devices, primary component from where user
sends and receives samples
–Delivery stations
–Receiving stations
• Manual
• Auto-unload-after unloading samples carrier automatically
returns to home station
–End or pass through

13. Components of PTS
• Master control unit-Microprocessor controlled-
Software monitors and controls the movement of
carriers
• Real time monitoring of transfer
• Speed at which carrier moves
• Carrier braking ensures soft landing

14. master control unit
• Can control up-to 512 stations in multiple
zones
• Can send and receive samples to each of the
stations
• automatically recognizes operating errors,
power failures and time-out errors

15. Carriers
• Transporting medium within PTS-Available in different sizes
• End opening, side opening, swivel top, screw cover, twist
open type
• RFID tagged-Each carrier has a unique identifier
• Allows home station to be assigned-Carrier automatically
returns to the home station after unloading samples
• Locking mechanism to prevent leakage

16. How PTS works
• Blood placed inside bags marked as biohazard
• Placed inside carrier
• X-ray/medicine can be placed directly in the container
• Carrier inserted inside station
• Destination is selected on the station
• Blower gets activated and pulls carrier
• Diverters direct carrier on the proper path
• Arrives at destination station
• Can be automatically unloaded and carrier returned

17. PTS in CNC, AIIMS

18. Advantages
• Increases turnaround time/Decrease material delivery
time
• Carriers transported at speed of 6-8 meters/sec
• Can transport up-to around 28 kg material @ speed of
8 meters/sec
• Less prone to human error
• Lesser staff requirement
• Less biohazard
• Lab services can be centralized
• Can connect multiple buildings
• Can be underground or overhead

19. Disadvantages
• Heat generated due to friction
• Speed of 8 m/s
• Rapid acceleration
• Bends with in a system- causes deceleration
• Excessive acceleration force-Damage to
erythrocyte-hemolysis
• Hemolysis can affect K, Mg, LDH, AST

20. Assessing sample quality
Hemolysis rates between samples delivered by human courier (10%) vs Pneumatic
tube (6%)- J Emerg Nurs. (2006)-No significant difference
In another study lesser hemolysis was reported if plain tube with gel is used- Ann Clin
Biochem (2004)
A recent study concluded no effect on hemolysis index and serum chemistry (LDH, K,
AST and creatinine) (Scientific chronicles, 2015)
Usage of padded containers, soft cushioned deceleration
Longer distance and greater speed can cause hemolysis
Data loggers sent through PTS to assess in real time the environmental conditions like
temperature, pressure, humidity and acceleration force

21. Blood gas analysis
• Analysis most sensitive to transportation- blood gas analysis
• pCO2 and pH not affected
• pO2 effected due to air contamination (Arch Pathol Lab Med,
1996)
• Purging of air bubbles before sending through PTS-changes in
pO2 insignificant
• pO2 was shown to be affected but use of pressure sealed
containers circumvented this –J Clin Pathol (2002)
• Recent studies show no affect on pO2-better PTS with
reduced speed and carefully prepared samples with no air
bubbles
• A recent study showed no impact of PTS on blood gas
analysis-Respir Care (2016)

22. Blood Bank
• PRBC, platelet concentrates and fresh frozen plasma -quality parameters
within normal reference range (Tanley et al, Transfusion, 1987)
• No difference in quality parameters of blood components following PTS
transport (Raturi et al, Glob TJ Transfus Med, 2016, Basu et al, Asian J of
Transfusion Science, 2015)
• Packed RBC (non irradiated and irradiated) could be safely transported
through PTS (Dhar et al, Asian J of Transfusion Sci, 2015)
• Effective for transport of blood products
• Thromboelastography results were shown in recent studies to be affected
by PTS transport (International J of Lab Hematology, 2016)

23. Hematological and coagulation
parameters
• No differences for complete blood cell count and
white cell differential parameter
• No difference in PT, APTT, fibrinogen or fibrin
monomers (Arch Pathol Lab Med, 2007)
• No affect on ESR
• Safe to transport through PTS

24. Limitations
• Samples of patients with high WBC malignancies-
transported via PTS-caused pseudohyperkalemia
• Lysis of WBC during transportation (Dickinson et
al, Pediatric Nephrology, 2012)
• In patients with very low hematological
parameters-PTS may not be appropriate-because
of fragile leucocyte membranes
• CSF samples -no significant changes in glucose,
lactate, erythrocyte counts, NOA or NBA. Small
but significant affect on protein (CCLM, 2016)
• pathology samples in formalin

25. PTS in leading hospitals
Stanford hospital PTS system
6.5 kms of tubing
Used 7000 times a day
Has 124 stations, 141 transfer units, 99 inter-
zonal connectors and 29 blowers
The longest distance from start to finish 1500
feet (around half a kilometer) covered in less
than 3 min

26. Conclusion
• PTS improves TAT and reduces cost
• Reduces inter departmental movement of
staff
• Most studies point to PTS being safe for
transportation
• Variation between different PTS due to
distance, speed, number of bends
• Laboratory should perform validation to
assess the impact of PTS transportation