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Bacterial shedding in common spine surgical procedures: headlamp/loupes and the operative microscope
Bradley K Weiner1, William B Kilgore
1Department of Orthopaedic Surgery, The Methodist Hospital/Texas Medical Center, Houston, TX 77030, USA. bkweiner@tmh.tmc.edu
Study Design:
Simulated discectomy was performed using 1) headlamp/loupes, 2) the operative microscope, or 3) neither; and bacterial shedding was assessed using air sampler/settle plate techniques.
Objectives:
To determine the potential contribution of these 2 commonly used systems of magnification/illumination to postoperative infection by using a controlled, experimental setting to limit confounding factors.
Summary Of Background Data:
Postoperative infections following surgery on the degenerative lumbar spine generally range from 0.6% to 6%. Headlamp/loupes and the operative microscope may contribute to potential infection, but, to date, the contribution to shedding rates while using these tools has not been assessed.
Methods:
Seventy samples from simulated discectomies within the usual sterile operative setting were collected using a 2-stage air sampler/settle plate technique. Group 1 (30 samples) used the operative microscope, Group 2 (30 samples) used headlamp/loupes, and Group 3 (10 samples) used neither as a control. Collected samples were examined for bacterial growth using blood agar plates and were assessed qualitatively and quantitatively.
Results:
Greater than half of the collected samples in Groups 1 and 2 demonstrated bacterial growth with coagulase negative Staphylococcus being found in nearly all positive samples and secondary species being common. No statistical differences between the 2 groups were noted for number of samples with growth, species of bacterial growth, number with growth of secondary species, or colony counts. Both groups demonstrated significantly greater number of samples with growth relative to the control Group 3.
Conclusions:
The use of headlamp/loupes or the operative microscope is associated with bacterial shedding. Proper techniques of cleaning, storage, and draping should be used to minimize their contribution to potential postoperative infection. No significant difference was noted between the 2 test groups, suggesting that infection risk should not come into play when choosing techniques of illumination/magnification.
Insights
Both headlamp/loupes and the operative microscope contribute to bacterial shedding during simulated spine surgery. Proper sterile techniques are crucial to minimize infection risk when using these common surgical tools.
Area of Science:
- Spine Surgery
- Surgical Infection Control
- Microbiology
Background:
- Postoperative infections in degenerative lumbar spine surgery range from 0.6% to 6%.
- Headlamp/loupes and operative microscopes are commonly used but their contribution to bacterial shedding has not been quantified.
- Understanding sources of contamination is key to reducing surgical site infections.
Purpose of the Study:
- To assess the bacterial shedding associated with headlamp/loupes versus the operative microscope.
- To determine if magnification and illumination systems contribute to bacterial contamination in the operating room.
- To provide data for informed decisions on surgical technique and infection prevention.
Main Methods:
- Simulated discectomy procedures were performed under controlled conditions.
- Bacterial shedding was measured using air sampler/settle plate techniques.
- Three groups were studied: operative microscope (n=30), headlamp/loupes (n=30), and a control group without magnification/illumination (n=10).
Main Results:
- Bacterial growth was detected in over half of samples from simulated discectomies using headlamp/loupes or the operative microscope.
- Coagulase-negative Staphylococcus was the predominant bacteria found.
- Both magnification/illumination groups showed significantly higher bacterial shedding compared to the control group, with no significant difference between the two groups.
Conclusions:
- The use of headlamp/loupes and the operative microscope is associated with increased bacterial shedding.
- Strict adherence to cleaning, storage, and draping protocols is essential to mitigate infection risk.
- The choice between headlamp/loupes and operative microscope should not be based on infection risk, as both contribute similarly to bacterial shedding.
