Robotic Endoscope Research Articles

Efficient Representation of Ducts and Cluttered Spaces for Realistic Motion Planning of Hyper-Redundant Robots through Confined Paths

Application of highly articulated hyper-redundant robots to manoeuvre in narrow and confined spaces is gaining popularity due to their obvious advantages. In this paper, we describe an optimization based approach for motion planning of hyper-redundant robots, which results in a natural motion of the links through ducts and confined spaces. It is shown that for a desired motion of the end-effector or the head of the hyper-redundant robot, the motion of the subsequent links attenuate and all the links avoid collision with the walls of the ducts and any other obstacles in the confined spaces. We discuss several ways to represent ducts in 2D and 3D space and also how the proposed algorithm is applied in these representations. It is shown that the complexity of the algorithm, with m constraints is at most O(m3.5) and in case where the ducts can be modeled with polyhedra, the complexity can be as low as O(m1.5). The proposed approach is also used to determine the largest link length in the hyper-redundant robot which can traverse the confined path. The concepts developed in this paper are demonstrated using simulations conducted on three practical scenarios: 1) hyper-redundant manipulators inspecting an industrial pipeline, 2) motion of an endoscopic robot through gastro-intestinal (GI) tract and 3) motion of hyper-redundant manipulators in search and rescue operations. Analysis on the computational complexity and the simulations shows that the method is feasible for practical implementation.

A Novel Robotic Endoscopic Device used for Operative Hysteroscopy

Video Objective To trial the use of a novel robotic endoscopic surgery platform for operative hysteroscopy. Setting A uterine tissue model with simulated polyps in various locations (Gynesim). Interventions The robotic endoscope is a surgical platform that simultaneously delivers two instruments that are 2-3mm in size using concentric tube technology. These instruments extend from the tip of a standard rigid endoscope outer sheath and are controlled robotically by an operator distant from the surgical field. In this pilot, a probe and monopolar needle were used to resect simulated endometrial polyps. Surgical principles of adequate exposure and traction and counter-traction are demonstrated. Conclusion The robotic endoscope platform may offer advantages over conventional hysteroscopy that could be useful for some applications. These advantages include: improved exposure, finer dissection capability, and use of two handed technique to allow traction and counter-traction. Further study regarding the safe, efficient, and cost-effective use of the robotic endoscope in gynecology is needed. To trial the use of a novel robotic endoscopic surgery platform for operative hysteroscopy. A uterine tissue model with simulated polyps in various locations (Gynesim). The robotic endoscope is a surgical platform that simultaneously delivers two instruments that are 2-3mm in size using concentric tube technology. These instruments extend from the tip of a standard rigid endoscope outer sheath and are controlled robotically by an operator distant from the surgical field. In this pilot, a probe and monopolar needle were used to resect simulated endometrial polyps. Surgical principles of adequate exposure and traction and counter-traction are demonstrated. The robotic endoscope platform may offer advantages over conventional hysteroscopy that could be useful for some applications. These advantages include: improved exposure, finer dissection capability, and use of two handed technique to allow traction and counter-traction. Further study regarding the safe, efficient, and cost-effective use of the robotic endoscope in gynecology is needed.

An Integrated Sensor-Model Approach for Haptic Feedback of Flexible Endoscopic Robots.

Haptic feedback for flexible endoscopic surgical robots is challenging due to space constraints for sensors and shape-dependent force hysteresis of tendon-sheath mechanisms (TSMs). This paper proposes (1) a single-axis fiber Bragg grating (FBG)-based force sensor for a TSM of a robotic arm and (2) an integrated sensor-model approach to estimate forces on other TSMs of that arm. With a robust and simple structure, a temperature-compensated sensor can be mounted on the distal sheath to measure forces applied by the TSM. This proposed sensor was integrated with a Ø4.2mm articulated robotic arm driven by six TSMs, with a measurement error of 0.37N in this work. The measurement from the single sensor was used to identify parameters in the force-transmission models of all other TSMs in the robot, realizing a one-sensor-for-all-distal-forces measurement method. The sensor-model approach could accurately estimate the distal force with an RMSE of 0.65N. An animal study was carried out to demonstrate the sensor's feasibility in real-life surgery. The sensor-model approach presented a robust, space-saving, and cost-effective solution for haptic feedback of endoscopic robots without any assumption on the shapes of the robot.

Deep learning for haptic feedback of flexible endoscopic robot without prior knowledge on sheath configuration

Distal-end force information is usually missing in flexible endoscopic robots due to the difficulties of mounting miniature force sensors on their end-effectors. This hurdle creates big challenges in providing a sense of touch for the operating surgeons. Many existing studies have developed models to calculate the distal-end forces based on the measured proximal-end forces of Tendon-Sheath Mechanisms (TSMs), but these models assume known sheath bending configuration which is unknown during real-life surgeries. This paper presents a two-stage data-driven method that makes dynamic distal-end force prediction of a flexible endoscopic robot without this assumption. In stage one, a convolutional neural network is used to estimate the sheath cumulative bending angle based on the proximal-end force responses of the robot to a probing signal; in stage two, a combination of two long-short-term-memory models pre-trained for the bending angles nearest to the estimated angle (obtained in stage one) makes dynamic estimations of the distal-end force of the robot. The proposed approach overcomes the challenges due to unknown TSM configurations and can robustly identify the correct force hysteresis phases of TSMs. The force prediction is continuous, accurate, and has a mean RMSE of 0.1711 N. This method was validated on an actual flexible surgical robot. In addition, since the proposed approach provides an estimation of the current system cumulative bending angle, it can also be used to facilitate the mathematical modeling methods which require information on the cumulative bending angle.

A Soft Pneumatic Inchworm Double balloon (SPID) for colonoscopy

The design of a smart robot for colonoscopy is challenging because of the limited available space, slippery internal surfaces, and tortuous 3D shape of the human colon. Locomotion forces applied by an endoscopic robot may damage the colonic wall and/or cause pain and discomfort to patients. This study reports a Soft Pneumatic Inchworm Double balloon (SPID) mini-robot for colonoscopy consisting of two balloons connected by a 3 degrees of freedom soft pneumatic actuator. SPID has an external diameter of 18 mm, a total length of 60 mm, and weighs 10 g. The balloons provide anchorage into the colonic wall for a bio-inspired inchworm locomotion. The proposed design reduces the pressure applied to the colonic wall and consequently pain and discomfort during the procedure. The mini-robot has been tested in a deformable plastic colon phantom of similar shape and dimensions to the human anatomy, exhibiting efficient locomotion by its ability to deform and negotiate flexures and bends. The mini-robot is made of elastomer and constructed from 3D printed components, hence with low production costs essential for a disposable device.

Robot-Assisted Endoscopic Resection: Current Status and Future Directions.

Therapeutic endoscopic resection has gained favor for its ability to achieve high en bloc and histologically complete resection rates via a minimally invasive approach. The main technical difficulties faced by interventionists are first the lack of traction causing suboptimal visualization of the dissection field and second, the lack of triangulation using existing therapeutic apparatuses. These challenges can be overcome with the use of robots and the multiple degrees of freedom afforded by the robotic wrists. Nevertheless, complications such as bleeding and perforation can occur. It is hence beneficial for the robotic device to be equipped with additional abilities such as suturing. Once the robotic prototypes have been fully optimized and marketed, a structured program should be instituted to ensure proper and adequate training of the end-users. The future of robotics should then explore the possibility of developing a soft robot or a robot with more natural human-like movements. A robot with a force feedback mechanism would be superior and improve safety. Eventually, a supervised autonomous robot may perform interventions with greater precision and accuracy than an expert procedurist. This review describes the benefits of robot-assisted endoscopic resections, recent developments aimed at managing iatrogenic complications and future directions for robotic endoscopy.

Tu2002 ROBOT-ASSISTED ESD VERSUS CONVENTIONAL ESD FOR COLONIC LESIONS: OUTCOMES OF A RANDOMIZED PILOT STUDY IN ENDOSCOPISTS WITHOUT PRIOR ESD EXPERIENCE

Endoscopic submucosal dissection (ESD) is becoming the preferred method for certain early gastrointestinal malignances, however, very few U.S. physicians have adopted this technique. This is in part due to the technically challenging nature of the procedure and the long learning curve. ESD is technically demanding, time consuming and bears high complication risks, but offers a higher en-blocresection rate compared to other endoscopic methods. Several endoscopic robots are currently under development in an attempt to make complex procedures more efficient and safe. Robotic-assisted endoscopy may have the potential to shorten learning curves, and broaden the adoption of complex endoscopic procedures such as ESD.

Robotic endoscopy, current status and future

Robotic endoscopy, current status and future

A Pilot Study of Endoscopic Submucosal Dissection Using an Endoscopic Assistive Robot in a Porcine Stomach Model.

Background/AimsEndoscopic assistive devices have been developed to reduce the complexity and improve the safety of surgeries involving the use of endoscopes. We developed an assistive robotic arm for endoscopic submucosal dissection (ESD) and evaluated its efficiency and safety in this in vitro pilot study.MethodsESD was performed using an auxiliary transluminal endoscopic robot. An in vitro test bed replicating the intra-abdominal environment and pig stomachs were used for the experiment. Participants were divided into skilled operators and unskilled operators. Each group performed ESD 10 times by using both conventional and robot-assisted methods. The perforation incidence, operation time, and resected mucous membrane size were measured.ResultsFor the conventional method, significant differences were noted between skilled and unskilled operators regarding operation time (11.3 minutes vs 26.7 minutes) and perforation incidence (0/10 vs 6/10). Unskilled operators showed a large decrease in the perforation incidence with the robot-assisted method (conventional method vs robot-assisted method, 6/10 vs 1/10). However, the operation time did not differ between the conventional and robot-assisted methods. On the other hand, skilled operators did not show differences in the operation time and perforation incidence between the conventional and robot-assisted methods. Among both skilled and unskilled operators, the operation time decreased with the robot-assisted method as the experiment proceeded.ConclusionsThe surgical safety of unskilled operators greatly improved with robotic assistance. Thus, our assistive robotic arm was beneficial for ESD. Our findings suggest that endoscopic assistive robots have positive effects on surgical safety.

Oncologic outcomes in patients treated with endoscopic robot assisted simple enucleation (ERASE) for renal cell carcinoma: Results from a tertiary referral center

IntroductionOpen Simple Enucleation (OSE) has been demonstrated to be an oncologically safe alternative to standard partial nephrectomy. We assessed the mid-term oncologic outcomes and predictors of disease recurrence in patients treated with Endoscopic Robot-Assisted Simple Enucleation (ERASE) verified through a standardized reporting system at a single institution. Material and methodsThe clinical data of patients treated with ERASE for renal cell carcinoma at our Institution from January 2012 to September 2018 were retrospectively reviewed. Surface-Intermediate-Base (SIB) score was evaluated immediately after surgery. Patients with a ≥2 SIB score were excluded. The local and distant recurrence rates, the recurrence-free (RFS), cancer-specific (CSS) and overall (OS) survival were assessed. Kaplan-Meier and log-rank test were used to estimate survivals and to compare recurrence-free survival. ResultsOverall, 259 patients were considered eligible for the present study. The median PADUA score was 7 (interquartile range [IQR] 6–9). Positive surgical margins (PSM) were registered in 7 (2.7%) cases. Median (IQR) follow-up time was 36 (27–51) months. Overall, 4 (1.5%) patients experienced systemic recurrence (SR) and 5 (1.9%) patients experienced local recurrence alone (LR) of whom 3 (1.1%) were on tumor resection bed, and 2 (0.8%) experienced recurrence elsewhere in the ipsilateral kidney. The 5-year RFS, CSS and OS were 94.2%, 98.9% and 93.6%, respectively. Higher nucleolar grade and PSM were the two factors significantly associated with worse RFS. ConclusionsERASE is a safe procedure, achieving negative surgical margins in the vast majority of patients and providing excellent mid-term local control and oncologic outcomes.

Robot-assisted endoscopic submucosal dissection versus conventional ESD for colorectal lesions: outcomes of a randomized pilot study in endoscopists without prior ESD experience (with video)

Endoscopic submucosal dissection (ESD) is becoming the preferred method for certain early GI malignancies; however, very few U.S. physicians have adopted this technique. This is in part because of the technically challenging nature of the procedure and the long learning curve. Several endoscopic robots are under development to address these complexities. This is a randomized, controlled, pilot study comparing conventional ESD versus robotic-assistedESD (RESD) in an exvivo bovine colon model. Five endoscopists without prior ESD or RESD experience were randomized into 2 groups (group 1, RESD after ESD; group 2, RESD before ESD). A standard template was used to create colonic lesions. The primary outcome was completeness of en bloc resection. Secondary outcomes included differences in procedure time, perforation rate, muscle injury rate, and National Aeronautical and Space Administration Task Load Index (NASA-TLX) to assess physical and mental workload. Five endoscopists each performed 4 tissue resections (2 RESD and 2 ESD), for a total of 20 procedures. Complete en bloc resection was achieved in all RESD and in 50% of ESD (P< .0001). The perforation rate was higher in the ESD group (60% vs 30%, P= .18). Total procedure time (34.1 vs 88.6 min, P= .001) and dissection time (27.8 vs 79.4 minutes, P= .002) were lower for RESD. The NASA-TLX also revealed better results for RESD (28.4 vs 47.4, P= .01). RESD appears to be more effective in obtaining en bloc resection with shorter procedure times and a lower perforation rate compared with conventional ESD as performed by ESD novices. RESD is also associated with lower physical and mental workloads.

Head-mounted interface for intuitive vision control and continuous surgical operation in a surgical robot system.

Although robot-assisted surgeries offer various advantages, the discontinuous surgical operation flow resulting from switching the control between the patient-side manipulators and the endoscopic robot arm can be improved to enhance the efficiency further. Therefore, in this study, a head-mounted master interface (HMI) that can be implemented to an existing surgical robot system and allows continuous surgical operation flow using the head motion is proposed. The proposed system includes an HMI, a four degrees of freedom endoscope control system, a simple three-dimensional endoscope, and a da Vinci Research Kit. Eight volunteers performed seven head movements and their data from HMI was collected to perform support vector machine (SVM) classification. Further, ten-fold cross-validation was performed to optimize its parameters. Using the ten-fold cross-validation result, the SVM classifier with the Gaussian kernel (σ = 0.85) was chosen, which had an accuracy of 92.28%. An endoscopic control algorithm was developed using the SVM classification result. A peg transfer task was conducted to check the time-related effect of HMI's usability on the system, and the paired t test result showed that the task completion time was reduced. Further, the time delay of the system was measured to be 0.72s. Graphical abstract A head-mounted master interface (HMI), which can be implemented to an existing surgical robot system, was developed to allow simultaneous surgical operation flow. The surgeon's head motion is detected through the proposed HMI and classified using a support vector machine to manipulate the endoscopic robotic arm. A classification accuracy of 92.28% was achieved.

A Modular Endoscopy Simulation Apparatus (MESA) for Robotic Medical Device Sensing and Control Validation

Much of ongoing robotic endoscope research is focused on locomotion, with only limited exploration into feedback control and autonomy in the unconventional and dynamic in vivo environment. This letter presents a modular endoscopy simulation apparatus (MESA) to quickly, affordably, and repeatedly test novel robotic endoscope control schemes in a synthetic colon at an accessible scale. The MESA allows for replication of many common physiologic barriers for current medical robotics, such as disturbances, patient positional changes, angulation of the colon, and a dynamic visual environment. The MESA will allow research teams to quickly and repeatedly validate new control strategies to minimize the effect of these physiological barriers before testing in costly in vivo procedures. The MESA platform and synthetic colon described in this letter have shown successful replication of colon geometry, visual appearance, peristaltic wave speeds and pressures, and disturbances from patient movement. The mold for the synthetic colon was built in sections to allow for geometry changes for future molds and has shown marked similarity to in vivo images from colonoscopies. The actuators chosen for the various controllable stages have proven ample power to produce maximum-case disturbances expected during procedures, and the stages are modular in structure to allow for a variety of testing scenarios. Inflatable rubber tubes and electronic solenoid valves are used to produce contractile forces, and have shown excess capability to reproduce physiological motility. The simulator presented here will aid in future feedback control, localization, and autonomy development for robotic endoscopes.

P140 - Assessment of Mid-Term oncologic outcomes in patients treated with Endoscopic Robot Assisted Simple Enucleation (ERASE) for renal cell carcinoma: Results from a tertiary referral centre

P140 - Assessment of Mid-Term oncologic outcomes in patients treated with Endoscopic Robot Assisted Simple Enucleation (ERASE) for renal cell carcinoma: Results from a tertiary referral centre

Global Evaluative Assessment of Robotic Skills in Endoscopy (GEARS-E): objective assessment tool for master and slave transluminal endoscopic robot.

Background and study aims The Master and Slave Transluminal Endoscopic Robot (MASTER) is a novel robotic endosurgical system with two operating arms that offer multiple degrees of freedom. We developed a new assessment tool, the Global Evaluative Assessment of Robotic Skills in Endoscopy (GEARS-E), derived from existing tools in laparoscopic and robotic surgery, and evaluated its utility in the performance of procedures using MASTER. Methods This was a pilot study conducted in vivo and ex vivo on animals. Three operators (Novice-1, Novice-2 and Expert) performed a total of five endoscopic submucosal dissections (ESD) using MASTER. Novice operators had no MASTER experience and the expert had previously performed eight MASTER ESDs. Operator performance was assessed by four independent evaluators using GEARS-E, which has a maximum score of 25 for five domains representing various skill-related variables (depth perception, bimanual dexterity, efficiency, tissue handling and autonomy). Results The mean global rating scores for Novice-1 first attempt, Novice-1 second attempt, Novice-2 first attempt, Novice-2 second attempt and Expertʼs cases were 13.0, 16.0, 13.3, 15.5, and 21.5, respectively. The mean scores of each of the five domains were statistically higher for the second attempts compared to the first attempts for both Novice-1 and Novice-2. The mean scores of each of the five domains for the Expertʼs case were consistently higher than those for the two novice operators in both their first and second attempts. Conclusion Results using GEARS-E showed correlations between surgical experience and MASTER ESD. As an assessment tool for evaluation of surgical skills, GEARS-E has great potential for application in MASTER procedures.

A Platform for Developing Robotic Navigation Strategies in a Deformable, Dynamic Environment

While in vivo robotic locomotion has demonstrated its potential through a number of means, sensing and closed-loop control for such devices have not been at the forefront of research. By enabling real-time navigation, capsule endoscopy could transform from passive capsule endoscopes (CEs) and remote-controlled robotic CE devices into semi- or fully autonomous, surgical tools. In this work, a novel robotic endoscope platform (REP) is designed and tested. This platform will be used to evaluate control, localization, and mapping techniques necessary to endow a robotic CE with autonomous features. REP performance was benchmarked against design requirements that included sensing, speed, and maneuverability. It was found that the REP could accelerate to a maximum speed of 80 mm/s in less than 0.2 s and could achieve a zero-point turning radius. Most significantly, a low-cost image segmentation algorithm was developed to enable real-time lumen navigation/center tracking. Visual navigation time trials were compared to manual user trials through a 90-degree turn in a deformable simulator, exhibiting mean run times 34% faster than manual users. This demonstrates the REP's maneuverability and sensing capabilities allowing for future implementation of a range of advanced sensing and control techniques ahead of robotic CE adoption.

Eye-in-Hand Visual Servoing of Concentric Tube Robots

This letter deals with the development of a vision-based controller for a continuum robot architecture. More precisely, the controlled robotic structure is based on three-tube concentric tube robot (CTR), an emerging paradigm to design accurate, miniaturized, and flexible endoscopic robots. This approach has grown considerably in the recent years finding applications in numerous surgical disciplines. In contrast to conventional robotic structures, CTR kinematics arise many challenges for an optimal control, such as friction, torsion, shear, and nonlinear constitutive behavior. In fact, in order to ensure efficient and reliable control, in addition to computing an analytical and complete kinematic model, it is also important to close the control loop. To do this, we developed an eye-in-hand visual servoing scheme using a millimeter-sized camera embedded at the robot's tip. Both the kinematic model and the visual servoing controller were successfully validated in simulation with visual servoing platform and using an experimental setup. The obtained results showed satisfactory performances for three-degrees of freedom positioning and path following tasks with adaptive gain control.

Robotic Bronchoscopy for Diagnosis of Suspected Lung Cancer: A Feasibility Study.

Robotic bronchoscopy may offer alternative approaches to address limitations of current bronchoscopic techniques for biopsy of suspected peripheral lung lesions. This study sought to evaluate complications and feasibility of robotic bronchoscopy performed with the Robotic Endoscopy System (RES). Adult patients from a single institution underwent bronchoscopy of suspected lesions with a bronchus sign with the RES. The primary outcome was complication rate, as assessed by the incidence of related serious adverse events (SAE). The secondary outcome was technical feasibility. Data are presented as median (range), counts, and percentage. P-value was calculated using the Mann-Whitney U test. Of 17 screened patients, 15 were eligible. The median age was 67 (38 to 79) years. The lesions (12 peripheral and 3 central) were located in the right lower lobe (33%), right upper lobe (27%), left upper lobe (27%), and left lower lobe (13%). No SAE, including pneumothorax and significant bleeding, occurred. Biopsy samples were obtained from 93% of patients. One sampling (right upper lobe) required conventional bronchoscopy and another required surgery to confirm malignancy. Cancer was confirmed in 60% (9/15) of patients. Benign features were found in 5 of 6 patients. Time to biopsy location reduced from 45 (21 to 84) minutes (first 5 cases) to 20 (7 to 47) minutes (last 9 cases), P=0.039. The study results and absence of SAE support feasibility of the RES in accessing the periphery of the lung. The RES has potential to address challenges associated with biopsy of peripheral lung lesions.

Animal study on master-slave system controlled robot-assisted flexible endoscopy in gastricendoscopy examination

Objective To evaluate the safety, feasibility and operational effectiveness of master-slave system controlled Robot-assisted flexible endoscopy 'YunSRobot’ in upper gastrointestinal endoscopy examination in living pigs. Methods Seven Guangxi BA-MA Mini-pigs underwent upper gastrointestinal endoscopy examination with master-slave system controlled Robot-assisted flexible endoscopy 'YunSRobot’ and Olympus GIF-Q260J gastroendoscope (Japan). The experiment divided into manual operation group and robot operation group. Nine gastroenterologists skilled with endoscopy operation handled the robot once in vitro to familiar with the mechanism and method of robot operation. And then performed manual operation and robot operation four times each. Endoscopy pictures and operation time were recorded. T test and one-way analysis of variance were performed for statistical analysis. Results Both manual operation and robot operation could successfully finish standard esophagus and stomach endoscopic examination. There were no complications such as hemorrhage, perforation, mistaken insertion into of trachea, injures of pharynx and larynx and inhalation pneumonia. Esophagus, gastric cardia, gastric fundus, gastric body, gastric angle, gastric antrum and gastric pylorus could be clearly observed in both groups. The manual operating time of nine gastroenterologists was (3.67±1.95) minutes, which was shorter than that of robot operating time ((7.60±2.00) minutes), and the difference was statistically significant (t=8.445, P<0.01). The time of first in vitro operation performed by nine gastroenterologist was (13.10±6.32) minutes. The operation times of each case of nine gastrienterologist were (8.49±0.90) minutes, (7.50±1.19) minutes, (7.30±1.33) minutes and (7.12±1.61) minutes. The difference was statistically significant (F=7.901, P<0.01). Operation time gradually shortened and operation proficiency significantly improved. Conclusion Master-slave system controlled Robot-assisted flexible endoscopy 'YunSRobot’ which provides a clear observation of esophagus and stomach is safe in endoscopic examination of living animal. Key words: Esophagoscopy; Gastroscopy; Animal experimentation; Flexible endoscope robotic system; YunSRobot; Digestive endoscope robot

The i2Snake Robotic Platform for Endoscopic Surgery

Endoscopic procedures have transformed minimally invasive surgery as they allow the examination and intervention on a patient’s anatomy through natural orifices, without the need for external incisions. However, the complexity of anatomical pathways and the limited dexterity of existing instruments, limit such procedures mainly to diagnosis and biopsies. This paper proposes a new robotic platform: the Intuitive imaging sensing navigated and kinematically enhanced (i^{2}Snake) robot that aims to improve the field of endoscopic surgery. The proposed robotic platform includes a snake-like robotic endoscope equipped with a camera, a light-source and two robotic instruments, supported with a robotic arm for global positioning and for insertion of the i^{2}Snake, and a master interface for master–slave teleoperation. The proposed robotic platform design focuses on ergonomics and intuitive control. The control workflow was first validated in simulation and then implemented on the robotic platform. The results are consistent with the simulation and show the clear clinical potential of the system. Limitations such as tendon backlash and elongation over time will be further investigated by means of combined hardware and software solutions. In conclusion, the proposed system contributes to the field of endoscopic surgical robots and could allow to perform more complex endoscopic surgical procedures while reducing patient trauma and recovery time.