Indicating shortcomings in surgical lighting systems

Guidelines in Practice: Design and Maintenance of the Surgical Suite

Hospital construction and renovation is an ongoing occurrence in the health care setting. The recently updated AORN "Guideline for design and maintenance of the surgical suite" provides perioperative nurses with information on the layout design and maintenance of perioperative spaces; safety measures to use during construction and renovation; monitoring and maintenance of the heating, ventilation, and air conditioning; and how to respond to unintended utility failures. This article provides an overview of the guideline and discusses recommendations for the interdisciplinary team, planning and designing the surgical suite, construction-related environmental contamination, ORs, and OR maintenance. It also includes a scenario describing specific concerns associated with the construction of an additional OR. Perioperative nurses should review the guideline in its entirety and apply the recommendations when participating in perioperative construction and renovation projects.

A timeline of surgical lighting - Is automated lighting the future?

High quality surgical lighting is central to successful performance in the operating room and therefore to both patient care and treatment. This article discusses the origins of surgical lighting from the 1800s to today, with a focus on the four main forms. Their uses, advantages, and disadvantages are evaluated in an effort to identify the improvements required to improve today's current state of surgical lighting. Whilst these four mainstream types have served well for the past thirty years, the literature exposes opportunities for improvement and can be used to guide the pathway to transition from manual conventional methods to a more automated lighting (AL) approach. The concept of AL has been proposed using established and known technical approaches such as artificial intelligence (AI), 3D sensor tracking algorithms and thermal imaging. Whilst AL seems incredibly promising, further focused research must be undertaken to maximise its' effectiveness and allow for successful integration of this new technology into operating rooms today.

Near-Field LED Illumination Strategies for Tonsillectomy and Adenoid Surgery

Objective: Perform a pilot feasibility study to demonstrate viability, quality, and safety advantages of light-emitting diode (LED) illumination when performing tonsillectomy. Study Design: Prospective cohort. Setting: Children's Hospital and Community Multispecialty Hospital. Methods: We tested a commercially available LED light, held in position with a minimally modified mouth gag, for off-label use in a "cavernous wound." We assessed surgeons', residents', and nurses' perceptions of function, safety, as well as preferences compared to headlights. Results: The light was used in 30 cases. Noted advantages over traditional lighting methods included superior brightness, stability and consistency of illumination, and the ability for others to assist more quickly. The inability to adjust brightness and/or the angle of light was an observed disadvantage. A small oral cavity or large tonsillar pillars creating a shadow required the temporary addition of a headlight. However, LED light use was not discontinued. Surgeons and residents reported a preference for not wearing a headlight, and nurses expressed concerns about headlight cleanliness. Conclusion: LED lighting technology demonstrated utility for teaching surgeons, residents, and nurses, and was perceived as safe. Additional specifications may make the light applicable to a wider variety of cases and could potentially mitigate headlight use during procedures of the oral cavity and oropharynx.Level of Evidence: 4.

A virtual reality simulation of a novel way to illuminate the surgical field - A feasibility study on the use of automated lighting systems in the operating theatre

Introduction

Surgical lighting systems have to be re-adjusted manually during surgery by the medical personnel. While some authors suggest that interaction with a surgical lighting system in the operating room might be a distractor, others support the idea that manual interaction with the surgical lighting system is a hygiene problem as pathogens might be present on the handle. In any case, it seems desirable to develop a novel approach to surgical lighting that minimizes the need for manual interaction during a surgical procedure.

Methodes

We investigated the effect of manual interaction with a classical surgical lighting system and simulated a proposed novel design of a surgical lighting system in a virtual reality environment with respect to performance accuracy as well as cognitive load (measured by electroencephalographical recordings).

Results

We found that manual interaction with the surgical lights has no effect on the quality of performance, yet for the price of a higher mental effort, possibly leading to faster fatigue of the medical personnel in the long run.

Discussion

Our proposed novel surgical lighting system negates the need for manual interaction and leads to a performance quality comparable to the classical lighting system, yet with less mental load for the surgical personnel.

Evaluation of an Improved Suspension System Concept for Surgical Luminaires

Surgeons have indicated ergonomic problems with the surgical luminaire, which have been observed to occur during repositioning. The possibility of singularity, within the movement space of the translational subsystem of the current double-arm suspension systems, is confirmed to be the cause of these problems. In this study, a redesign of the translational subsystem is compared to the conventional translational subsystem. A user experiment with 14 participants is setup to compare the redesigned and alternative system. The experiment is performed outside the operating room (OR), with one setup that can be altered between two designs; an uncoupled state with the kinematics of the conventional subsystem, and a coupled state with the redesigned kinematics. Work cost, duration, and jerk cost are compared, as well as NASA TLX score. The work cost of a movement in the conventional uncoupled state is confirmed to depend on the spatial orientation of the mechanism, which is not the case in the new coupled state. Due to these different kinetics, the movement patterns with the coupled mechanism are more consistent between participants, the duration of movements is shorter, less problems occur, and participants are able to better control the movements as demonstrated by lower jerk costs. This result validates the redesign and confirms the hypothesis that a translational subsystem without the possibility of singularity within its movement space will improve luminaire repositioning. The conceptual design can now be used as base for a clinically usable design.

Current State of Surgical Lighting

Surgical performance in the operating room (OR) is supported by effective illumination, which mitigates the inherent environmental, operational, and visual challenges associated with surgery. Three critical components are essential to optimize operating light as illumination: (1) centering on the surgeon's immediate field, (2) illuminating a wide or narrow field with high-intensity light, and (3) penetrating into a cavity or under a flap. Furthermore, optimal surgical illumination reduces shadow, glare, and artifact in visualization of the surgical site. However, achieving these principles is more complex than at first glance, requiring a detailed examination of the variables that comprise surgical illumination. In brief, efficacious surgical illumination combines sufficient ambient light with the ability to apply focused light at specific operative stages and angles. But, brighter is not always merely better; rather, a nuanced approach, cognizant of the challenges inherent in the OR theater, can provide for a thoughtful exploration of how surgical illumination can be utilized to the best of its ability, ensuring a safe and smooth surgery for all.

Lightfield adaptable surgical luminaire concept

Visual performance and visual comfort are a combined effect of the illumination characteristics and the illuminated objects. Current surgical lighting systems have a fixed shape illumination pattern, whereas the wound and surroundings have a variable shape and characteristics. A lighting system that is able to adapt its shape and light distribution to the characteristics of the wound might improve visual performance. This paper describes the development of a new concept for lighting using bendable strips with LEDs. The basic idea of placing LEDs on a bendable surface is very simple and elegant. To achieve a functional system, the effects of the different design choices, such as shape of the strips, number of LEDs, number of strips, and LED power were investigated. The influence of these choices is evaluated by simulation using a computational model to identify the optimal parameters for the design. The final design is evaluated using the computational model and a physical prototype consisting of one luminaire segment. The system is able to produce light fields that can have fairly complex shapes at a good range of different sizes. Recommendations about aspects like spot size and strip number are given. The physical test model indicates that the calculated system functions close to how it would in a real-life situation. Given the results, it expected that a system, which is able to modify the light field in real time and that requires minimal control effort, could improve lighting in the operating room.

Illumination in Spinal Surgery Depending on Different Approaches and Light Sources

BACKGROUND

Sufficient visualization of the operating field is crucial for success in surgery and is important especially concerning minimally invasive and deep approaches in spine surgery.

METHODS

The spinal microsurgical approach was imitated using an isolated box that was accessed with different devices. Different light sources and auxiliary devices were analyzed and compared. Light sources used were a microscope, a standard operating room lamp, and a headlamp. The auxiliary devices included different tubes with and without optical light fibers, different retractors, and an endoscope.

RESULTS

We demonstrated that different combinations of light sources and auxiliary devices provide significantly different illumination in the artificial operating field. A tube with optical fibers seems to be superior for nonmicroscopic approaches. The smaller these tubes are in diameter, the higher the illuminance on the surgical focus.

CONCLUSIONS

The combination of tube and microscope seems to be the best choice for deep approaches in microsurgical spinal surgery. An endoscope supplies illuminance comparable to a surgical microscope.

Safety, Performance, and Satisfaction Outcomes in the Operating Room: A Literature Review

OBJECTIVE

This review of empirical literature focuses on the design of operating rooms (ORs) by investigating the physical environmental features of ORs associated with patient and staff outcomes.

BACKGROUND

Many ORs built more than 30 years ago remain operational today. However, most are inadequately designed to handle the equipment, processes, and people that a contemporary OR needs to accommodate. However, the evidence base for designing ORs has been sorely lacking, and little guidance exists on how OR design can improve safety and performance outcomes.

METHOD

A literature search was conducted using PubMed and the university's linked databases. The inclusion criteria included peer-reviewed journal articles that reported some aspect of the physical environment of ORs along with outcomes. The study included empirical studies as well as nonempirical best practice papers.

RESULTS

This literature review uncovered 211 articles. The main themes that emerged include OR design-related factors, ventilation, temperature and humidity, acoustical environment, lighting, and materials. Some environmental threats to patient safety in the OR include frequent door openings, clutter, poor air quality, surface contamination, and noise. Further, staff performance and satisfaction were impacted by factors such as the OR layout and equipment and furniture ergonomics.

CONCLUSION

This literature review provides an overview of the research organized into design-focused topic areas to support decision-making by architects and designers. This article highlights gaps in the research and identifies areas where best practice and design assumptions need to be evaluated using rigorous design research.

Optimal illumination for visual enhancement based on color entropy evaluation

Object visualization is influenced by the spectral distribution of an illuminant impinging upon it. In this paper, we proposed a color entropy evaluation method to provide the optimal illumination that best helps surgeons distinguish tissue features. The target-specific optimal illumination was obtained by maximizing the color entropy value of our sample tissue, whose spectral reflectance was measured using multispectral imaging. Sample images captured under optimal light were compared with that under commercial white light emitting diodes (3000K, 4000K and 5500K). Results showed images under the optimized illuminant had better visual performance such as more subtle details exhibited.

Surgical lighting with contrast enhancement based on spectral reflectance comparison and entropy analysis

Surgical light is important for helping the surgeon easily identify specific tissues during an operation. We propose a spectral reflectance comparison model to optimize the light-emitting diode light spectrum in the operating room. An entropy evaluation method, meant specifically for surgical situations, was developed to evaluate images of biological samples. White light was mixed to achieve an optimal spectrum, and images of different tissues under the light were captured and analyzed. Results showed that images obtained with light with an optimal spectrum had a higher contrast than those obtained with a commercial white light of different color temperatures. Optimized surgical light obtained using this simple and effective method could replace the traditional surgical illumination systems.

Rayfiles including spectral and colorimetric information

To obtain realistic results in lighting simulation software, realistic models of light sources are needed. A near-field model of a light source is accurate, and can be obtained by a near-field goniophotometer. This type of goniophotometer is conventionally equipped with a V(λ)-filter. However, the advent of new light sources with spatial- or angular color variations necessitates the inclusion of spectral information about the source. We demonstrate a method to include spectral information of a light source in ray tracing. We measured the relative angular variation of the spectrum of an OLED using a spectroradiometer mounted on a near-field goniophotometer. Principal component analysis (PCA) is exploited to reduce the amount of data that needs to be stored. Also a photometric ray file of the OLED was obtained. To construct a set of monochromatic ray files, the luminous flux in the original ray file is redistributed over a set of wavelengths and stored in separate ray files. The redistribution depends on the angle of emission and the spectral irradiance measured in that direction. These ray files are then inserted in ray tracing software TracePro. Using the OLED as a test source, the absolute spectral irradiance is calculated at an arbitrary position. The result is validated using a spectroradiometer to obtain the absolute spectral irradiance at that particular point. A good agreement between the simulated and measured absolute spectral irradiance is found. Furthermore, a set of tristimulus ray files is constructed and used in ray tracing software to generate a u'v'-color coordinate distribution on a surface. These values are in agreement with the color coordinate distribution found using the spectral ray files. Whenever spectral or color information is desired at a task area, the proposed method allows for a fast and efficient way to improve the accuracy of simulations using ray tracing.

Feasibility of touch-less control of operating room lights

PURPOSE

Today's highly technical operating rooms lead to fairly complex surgical workflows where the surgeon has to interact with a number of devices, including the operating room light. Hence, ideally, the surgeon could direct the light without major disruption of his work. We studied whether a gesture tracking-based control of an automated operating room light is feasible.

METHODS

So far, there has been little research on control approaches for operating lights. We have implemented an exemplary setup to mimic an automated light controlled by a gesture tracking system. The setup includes a articulated arm to position the light source and an off-the-shelf RGBD camera to detect the user interaction. We assessed the tracking performance using a robot-mounted hand phantom and ran a number of tests with 18 volunteers to evaluate the potential of touch-less light control.

RESULTS

All test persons were comfortable with using the gesture-based system and quickly learned how to move a light spot on flat surface. The hand tracking error is direction-dependent and in the range of several centimeters, with a standard deviation of less than 1 mm and up to 3.5 mm orthogonal and parallel to the finger orientation, respectively. However, the subjects had no problems following even more complex paths with a width of less than 10 cm. The average speed was 0.15 m/s, and even initially slow subjects improved over time. Gestures to initiate control can be performed in approximately 2 s. Two-thirds of the subjects considered gesture control to be simple, and a majority considered it to be rather efficient.

CONCLUSIONS

Implementation of an automated operating room light and touch-less control using an RGBD camera for gesture tracking is feasible. The remaining tracking error does not affect smooth control, and the use of the system is intuitive even for inexperienced users.

A simulation model that predicts handling forces required to reposition surgical lights

INTRODUCTION

High handling forces of surgical lighting systems limit their usability. To make improvements to the mechanical design of the system the behaviour of the system should be understood. Therefore, this study presents a model that predicts handling forces of surgical lighting systems.

METHODS

Geometry and joint friction torques of a real lighting system were measured and implemented in a validated force model. Mean, standard deviation within the spatial region, minimum force and maximum force were computed for three different regions of the working area.

RESULTS

The mean (standard deviation within the spatial region) forces were 129 (106) N in the centre region, and 61 (14) N and 60 (17) N in more offcentre regions.

CONCLUSION

The simulation results showed high handling forces in the central region, explaining the observed repositioning patterns of the surgical light during surgery. The model can also be used to compare different lighting systems, or to evaluate the effect of design changes.

Evaluation of a new surgical light source for difficult visibility procedures

A new lighting device for open surgery of difficult access wounds was designed: the Extender add-on. The performance of the Extender is evaluated and compared with the conventional solutions used in the operating room (OR) on illumination quality. A cylindrical setup was built to measure the distribution of light in a simulated pelvic wound. The light was provided by a head-mounted light, an OR light, and a pair of Extender prototypes. The results showed that the Extender prototypes provided 12.2 lumens inside the wound, whereas the head-mounted light gave 5.7 lumens. The Extenders provided smoothly angular distributed light from 0° to 180°, whereas the head-mounted light and OR light only provided light from 115° to 180°. The Extender prototypes had a promising performance in terms of light distribution. It is expected that a more accurately produced Extender will increase performance in terms of illumination quantity and illumination distribution smoothness even further.