The use of the SurgiCube over critical zones and instruments to reduce air-borne contamination at intraocular ophthalmic surgeries Oogartsen Praktijk Delfland, Eye clinic Delft, The Netherlands August & September 2016 1/10 Clinical Info
Content OBJECTIVE OF THE MEASUREMENTS... 3 MEASUREMENT METHOD... 3 CFU BACTERIA SAMPLING... 3 PARTICULATE SAMPLING... 3 ENDPOINTS... 4 CONDITIONS... 4 PATIENT DATA... 5 SUMMARY OF MEASUREMENT RESULTS... 7 CFU AND PARTICLE MEASUREMENT AT CRITICAL ZONE MONDAY AUGUST 29 2016... 7 CFU AND PARTICLE MEASUREMENT AT CRITICAL ZONE MONDAY SEPTEMBER 19 2016... 7 AGAR PLATE PICTURES... 8 CONCLUSION... 9 APPENDIX 1 MEASUREMENT SITE 10 2/10 Clinical Info
Objective of the measurements The objective is to determine if SurgiCube reduces air-borne colony forming units (e.g. bacteria), hereafter referred to as CFU, to a level below 5 CFU during intraocular ophthalmic surgeries near the surgical site and over instruments. Comparison shall be made to ambient air in the room without the clean air flow from SurgiCube, here referred to as Reference. Measurement method Measurements on the bacteria occurrence over the critical zone and instruments were carried out during 26 authentic cataract surgeries, on August 29 and September 19 year 2016, at Oogartsen Praktijk Delfland (OAPD), Delft, The Netherlands. Prior to using the SurgiCube on patients, simulated measurements and performance tests have been done in Delft and in other locations where the SurgiCube is installed. This report shows the results from the authentic surgical ophthalmic procedures. CFU Bacteria sampling The bacteria sampling was carried out by using two calibrated active CFU samplers equipped with sterile silicone tubing of 39ʺ each with a sterilized stainless steel probe. This way the active air samplers themselves, using Trypton Soya Agar (TSA) agar plates, could be positioned outside the critical zone. One sterile probe was positioned in the critical zone over the instruments and as near the surgical site as possible (referred to as location A in report) and one sterile probe was positioned in the ambient reference area (location B). Just like the change of the TSA agar plate also the tubing and probe were changed for every single surgical procedure. The TSA agar plates were incubated for 7 days at 30-35 C. At each measurement cycle 1m 3 (1000 litres) of air was sampled in 10 minutes. Particulate sampling To evaluate the effect of the HEPA filtered air flow, particulates were sampled in the critical zone over the instruments and as near the surgical site as possible (referred to as location A in report) as well as in the ambient area (location B) for reference. Particles of certain sizes can carry bacteria and therefore filtering out these particles by multiple filters attributes to prevention of airborne contamination. Two calibrated particle counters with tubing of 39ʺ each with sterile stainless steel probes were used. This way the particle counters themselves could be positioned outside the critical zone. Tubing and probe were changed for every single surgical procedure. Raw differential particulate sizes of 0.3µm, 0.5μm, 1.0µm and 5.0μm are sampled in the air for 10 minutes. Based on ISO14644-1 1999 for ISO classification of the measured air we report both 0.5µm and 5.0µm particle sizes. Based on ISO14644-1 (2015) only 0.5µm particle size is used for ISO classification of the measured air in this report. 3/10 Clinical Info
Endpoints: The primary outcome is to determine the CFU level in the air at the surgical site and over instruments. The secondary endpoint is to determine the number of particles in the air at the surgical site and over instruments. Conditions The ventilation system in the surgery room consisted of two air inlets and two air outlets. The SurgiCube is positioned in the middle. The critical zone was supplied with pre-filtered (G3, F7) and HEPA (H14) filtered air from the air zone unit SurgiCube to protect both sterile instruments and the surgical site from contamination by particulate matter. The surgery room had a size of 237ft 2. A medical team of 3 people were present in the room: the surgeon, the scrub nurse and a circulator. Two technicians performing all the measurements were also present in the room. All people wore scrubs, head caps, mouth masks and gloves and the medical team wore sterile gowns. The technicians only operated the air samplers and counters and changed the agar plates, tubing and probes. The medical team worked according their standard procedures and protocols and did not have to change anything for the measurements. Normal activity took place for performing intraocular ophthalmic surgery in the room. The number of door openings and any other remarks were registered case by case as shown in the patient / case data. 4/10 Clinical Info
Patient data Patient data August 29 2016 Patient Gender Date of birth Procedure Duration 1 F 6-9-1945 Cataract 18min 2 M 28-11-1954 Cataract 9min 3 M 17-10-1947 Cataract 10min 4 F 11-12-1928 Cataract 16min 5 F 27-9-1935 Cataract 11min 6 M 23-5-1957 Cataract 10min 7 F 9-1-1943 Cataract 12min 8 F 26-2-1957 Cataract 10min 9 M 20-8-1940 Cataract 9min 10 M 3-4-1939 Cataract 11min 11 F 14-12-1924 Cataract 10min 12 F 16-10-1936 Cataract 10min 13 F 24-12-1931 Cataract 9min Case Plate locations Plate Lab ID nr Door openings Remarks 1 Meting 1 loc A + B A14.367 / B14.368 4 Starting problem phaco machine 2 Meting 2 loc A + B A14.369 / B14.370 2 3 Meting 3 loc A + B A14.371 / B14.372 3 4 Meting 4 loc A + B A14.373 / B14.374 5 5 Meting 5 loc A + B A14.375 / B14.376 5 6 Meting 6 loc A + B A14.377 / B14.378 5 7 Meting 7 loc A + B A14.379 / B14.380 6 8 Meting 8 loc A + B A14.381 / B14.382 3 9 Meting 9 loc A + B A14.383 / B14.384 4 10 Meting 10 loc A + B A14.385 / B14.386 2 11 Meting 11 loc A + B A14.387 / B14.388 3 12 Meting 12 loc A + B A14.389 / B14.390 2 13 Meting 13 loc A + B A14.391 / B14.392 4 Cleaning microscope lens; phaco problem; patient arm movements and drape against probe 5/10 Clinical Info
Patient data September 19 2016 Patient Gender Date of birth Procedure Duration 14 M 16-7-1943 Cataract 9min 15 M 19-5-1938 Cataract 10min 16 M 9-2-1952 Cataract 10min 17 M 28-3-1946 Cataract 13min 18 F 7-4-1927 Cataract 8min 19 F 21-2-1943 Cataract 9min 20 F 21-8-1946 Cataract 11min 21 F 24-3-1928 Cataract 11min 22 F 30-1-1950 Cataract 8min 23 M 10-2-1959 Cataract 10min 24 F 18-5-1933 Cataract 11min 25 F 3-5-1958 Cataract 8min 26 M 19-12-1934 Cataract 9min Case Plate locations Plate Lab ID nr Door openings Remarks 14 Meting 1 loc A + B A15.659 / B15.660 0 15 Meting 2 loc A + B A15.661 / B15.662 0 16 Meting 3 loc A + B A15.663 / B15.664 2 17 Meting 4 loc A + B A15.665 / B15.666 Phaco problem, bring new tubing, lot of movement at 4 instrument table 18 Meting 5 loc A + B A15.667 / B15.668 2 19 Meting 6 loc A + B A15.669 / B15.670 4 20 Meting 7 loc A + B A15.671 / B15.672 4 21 Meting 8 loc A + B A15.673 / B15.674 4 22 Meting 9 loc A + B A15.675 / B15.676 1 23 Meting 10 loc A + B A15.677 / B15.678 3 24 Meting 11 loc A + B A15.679 / B15.680 5 25 Meting 12 loc A + B A15.681 / B15.682 3 26 Meting 13 loc A + B A15.683 / B15.684 4 6/10 Clinical Info
Summary of measurement results CFU and Particle measurement at critical zone Monday August 29 2016 CFU and Particle measurement at critical zone Monday September 19 2016 7/10 Clinical Info
Agar plate pictures Batch Control only for incubation reference Agar plate from the critical zone in the SurgiCube Agar plate from the ambient background reference area 8/10 Clinical Info
Conclusion The test results within a group of 26 patients clearly show that there is a significant difference in the occurrence of bacteria and particulates when the surgery site and instruments are provided with particulate free air from the air zone unit SurgiCube compared to the ambient background reference air in the room. The bacteria counting result showed that the difference was as prominent as more than 126 times less CFU per m³ (15.19 in background vs. 0.12 inside Surgicube). To verify the efficiency from the HEPA filtrated air, particles were sampled simultaneously. From a particles point of view the difference was significant. Approximately 470 times less particles of 0.5µm per m³ (313821 in background vs. 666 inside Surgicube) and approximately 725 times less particles of 5.0µm per m³ (1952 in background vs. 2.69 in Surgicube). In conclusion, and referring to the statistical analysis, it is considered to be statistically valid that the particulate free air from the air zone unit SurgiCube is very effective to use over the critical zone to reduce the levels of airborne bacteria carrying particles which could be a cause for airborne contamination and therefore post-operative infections. 9/10 Clinical Info
Appendix 1 Measurement site Tube for Active Air Sampler Tube and probe for Particle Counter Tube with probe for Active Air Sampler 10/10 Clinical Info