Immersive Virtual Reality to potentiate hypnosis: an innovative and powerful approach to support surgery

Introduction

Since it was first developed, virtual reality (VR) has been ceaselessly improving, advancing at an exponential rate over the past few years [1] Cipresso P, Giglioli IAC, Raya MA, Riva G. The Past, Present, and Future of Virtual and Augmented Reality Research: A Network and Cluster Analysis of the Literature. Front Psychol. 2018;9:2086..

The earliest VR systems were based on concepts developed in cybernetics: an artificial system that is capable of intensifying sensory stimuli, removing the user from their real environment and placing them in an artificial one [2] Herbelin B. SA, Salomon R. and Blanke O. . Neural mechanisms of bodily self-consciousness and the experience of presence in virtual reality. . 2016; Human Computer Confluence, Riva G. Ed., De Gruyter Publisher, Chapter 3.. This perspective led to the quest for totally immersive systems that would be able to entirely encapsulate the human body and senses. Immersion is the point of entry into VR, providing the conditions to set the cognitive processes in motion. It is defined as the capacity of a VR system to create the perception in the user that they have been relocated into what is known as an immersive virtual environment [3] Slater M. A note on Presence terminology. Presence-Connect, 3(1) Jan 2003 On-line: http://presencecsuclacuk/presenceconnect/. 2003.. This high-level immersion of the individual in the VR is made possible by multisensory integration [4] Randy Pausch1 DP, George Williams2. Quantifying immersion in virtual reality. SIGGRAPH '97: Proceedings of the 24th annual conference on Computer graphics and interactive techniques. 1997., and the neurocognitive mechanisms underlying this are still being examined in cross-disciplinary studies in engineering and the cognitive sciences [5] Riva G, Wiederhold BK, Mantovani F. Neuroscience of Virtual Reality: From Virtual Exposure to Embodied Medicine. Cyberpsychol Behav Soc Netw. 2019;22(1):82-96..

The surgical applications of VR are expanding rapidly. Some examples of these are dexterity training (technical skills), anatomy training and planning surgical procedures. Education and training currently appear to be the main fields of application for VR in surgery [6] Pia Vayssiere PEC, Bruno Herbelin, Olaf Blanke, Karl Schallera,, Bijlenga P. Application of virtual reality in neurosurgery: Patient missing. A systematic review. Journal of Clinical Neuroscience. 2021..

VR could also be used to offer more direct benefits to patients in surgery. In our current way of thinking, the success of surgery is too often focused on the surgeons and their ability to perform an intervention. However, beyond the intervention itself, the way in which patients respond to the intervention also has an impact on post-operative outcomes. The perception of the patient is an integral factor in the success of their care. When a patient becomes an active and involved partner their own care, they develop a sense of autonomy and self-determination, which plays a role in the patient becoming or remaining invested in self-management [7] Gruyter D. Nursing care and outcome in surgical patients – why do we have to care? Innovative Surgical Sciences. 2019;Volume 4 Issue 4..

There are a growing number of studies that support the efficacy of hypnosis and hypnotic therapies in acute pain [8] Patterson DR, Jensen MP. Hypnosis and clinical pain. Psychol Bull. 2003;129(4):495-521., chronic pain [9] Elkins G, Jensen MP, Patterson DR. Hypnotherapy for the management of chronic pain. Int J Clin Exp Hypn. 2007;55(3):275-287. and anxiety [10] Golden WL. Cognitive hypnotherapy for anxiety disorders. Am J Clin Hypn. 2012;54(4):263-274.. Unlike pharmacological management using analgesic medications for pain, which can incur significant financial costs (due to the need for continued usage), have unpleasant side effects and involve social costs (associated with issues of misappropriation), hypnosis interventions are relatively simple and low-cost to provide. There are numerous benefits, such as an improved sense of being able to control the pain and its impact, and feelings of well-being. The negative side effects are minor [11] Jensen MP, McArthur KD, Barber J, et al. Satisfaction with, and the beneficial side effects of, hypnotic analgesia. Int J Clin Exp Hypn. 2006;54(4):432-447..

The purpose of this work, then, is to carry out a literature review to demonstrate the potential offered by the combination of virtual reality and hypnosis in the population of “surgical” patients, who are particularly vulnerable to stress and anxiety.

Stress and anxiety in surgical patients

Patients admitted to hospital often feel physical, emotional and social distress, and this is exacerbated by a radical change to their lifestyle, the loss of their usual rights and privileges and a high prevalence of pain [12] Henderson AR. Reference Corner. J Clin Ultrasound 4 (5), 378–383 doi:101002/jcu1870040518. 1976;4 (5), 378–383.. More than half of all patients admitted to hospital experience pain [13] Helfand M, Freeman M. Assessment and management of acute pain in adult medical inpatients: a systematic review. Pain Med. 2009;10(7):1183-1199.. In order to take a rounded view of patient management, hospital clinicians need to consider not only the physical impact of the disease on their patient, but also the psychological and social impact. However, the dynamic pace of hospital medicine, with the small amount of time available to dedicate to each patient, is an obstacle to offering holistic care to hospitalised patients.

Over 230 million people globally undergo an operation every year, and this figure is continually on the rise [14] Weiser TG, Regenbogen SE, Thompson KD, et al. An estimation of the global volume of surgery: a modelling strategy based on available data. Lancet. 2008;372(9633):139-144..

Pre-operative anxiety is a common phenomenon in patients waiting to have surgery [15] Wilson CJ, Mitchelson AJ, Tzeng TH, et al. Caring for the surgically anxious patient: a review of the interventions and a guide to optimizing surgical outcomes. Am J Surg. 2016;212(1):151-159.. This anxiety can be a contributing factor to a sense of discomfort throughout the whole peri operative process [16] Aust H, Eberhart L, Sturm T, et al. A cross-sectional study on preoperative anxiety in adults. J Psychosom Res. 2018;111:133-139.. Individuals who are preparing for an operation often feel less sure of themselves, as well as being tense and stressed, because they believe that they are in an unpredictable situation [17] J.J. Nagelhout SEE. Nurse Anesthesia. 2017;Elsevier, St. Louis, MO . The operation itself and being under general anaesthesia represent two of the most anxiogenic events in the patient’s life [18] Egbert LD, Battit G, Turndorf H, Beecher HK. The value of the preoperative visit by an anesthetist. A study of doctor-patient rapport. JAMA. 1963;185(7):553-555., and are characterised by three separate negative components: fear of the unknown, the idea of being ill and the possibility of the end of life [19] Kindler CH, Harms C, Amsler F, Ihde-Scholl T, Scheidegger D. The visual analog scale allows effective measurement of preoperative anxiety and detection of patients' anesthetic concerns. Anesth Analg. 2000;90(3):706-712..

However, the clinical management of pain after an operation is far from being a success, in spite of a dramatic expansion in scientific studies in this field. Many patients suffer from intense pain after a surgical intervention [20] Gerbershagen HJ, Pogatzki-Zahn E, Aduckathil S, et al. Procedure-specific risk factor analysis for the development of severe postoperative pain. Anesthesiology. 2014;120(5):1237-1245.. A state of anxiety before the operation, a tendency to amplify pain and the acute pain experienced in the days after the operation are all factors that increase the risk of suffering from chronic pain three months after the operation, irrespective of the type of surgical intervention [21] Masselin-Dubois A, Attal N, Fletcher D, et al. Are psychological predictors of chronic postsurgical pain dependent on the surgical model? A comparison of total knee arthroplasty and breast surgery for cancer. J Pain. 2013;14(8):854-864.. Post-operative pain is a complex and specific issue that requires an effective treatment to reduce suffering, prevent complications and encourage recovery and rehabilitation [22] Pogatzki-Zahn EM, Segelcke D, Schug SA. Postoperative pain-from mechanisms to treatment. Pain Rep. 2017;2(2):e588.. Adequate pain relief offers access to quicker rehabilitation, earlier mobilisation, greater patient satisfaction and a faster discharge from hospital [23] Rytter S, Jensen BG, Munk S, Hovsgaard SJ, Hansen TB. A prospective study of day of surgery discharge in 368 consecutive patients with unicompartmental knee replacement. Dan Med J. 2019;66(9)..

The patient’s pain is usually managed by analgesic mediations. However, there are currently strong arguments for and a growing interest in developing complementary non-pharmacological strategies for pain management. One such approach is hypnosis in virtual reality, an innovative technique that involves delivering hypnotherapy to patients, inducing “a state of consciousness that implies focalised attention and reduced peripheral consciousness” [24] Elkins GR, Barabasz AF, Council JR, Spiegel D. Advancing research and practice: the revised APA Division 30 definition of hypnosis. Int J Clin Exp Hypn. 2015;63(1):1-9. and combining this with VR, which is a computer-generated environment that immerses the user in an artificial world.

Hypnosys

Hypnosis has existed in western societies for at least 200 years. It is a psychotherapy technique that places major significance on the notion of presence [25] Saadat H, Drummond-Lewis J, Maranets I, et al. Hypnosis reduces preoperative anxiety in adult patients. Anesth Analg. 2006;102(5):1394-1396..

In hospital, hypnosis is used to achieve a specific therapeutic objective. It involves inducing, through spoken prompts, a state of consciousness that is modified or “dissociated”. In this state, attention is focused and the patient becomes more receptive to suggestions (Figure 1 A, b). Hypnotherapy makes use of this unique state of consciousness to guide and assist the patient in changing their perceptions of pain or negative states, such as anxiety.

A hypnotic state, sometimes called a trance, is often defined as a spontaneous or induced state of consciousness, with the attention focused on something important, combined with reduced peripheral consciousness [26] Kohen DP, Kaiser P. Clinical Hypnosis with Children and Adolescents-What? Why? How?: Origins, Applications, and Efficacy. Children (Basel). 2014;1(2):74-98.. An individual in a trance also has an increased capacity to respond to suggestions [26] Kohen DP, Kaiser P. Clinical Hypnosis with Children and Adolescents-What? Why? How?: Origins, Applications, and Efficacy. Children (Basel). 2014;1(2):74-98.. These suggestions may lead to changes in the sensations, perceptions, emotions, thoughts and behaviours of the patient [27] Jensen MP, Jamieson GA, Lutz A, et al. New directions in hypnosis research: strategies for advancing the cognitive and clinical neuroscience of hypnosis. Neurosci Conscious. 2017;3(1).. An individual who responds to suggestions under hypnosis is often referred to as hypnotisable. To make the patient more receptive to suggestions, the therapist can help them to enter into a trance state by using specific techniques (prompts), such as fixing the eyes on a point, gradually relaxing the muscles or guided imagery [27] Jensen MP, Jamieson GA, Lutz A, et al. New directions in hypnosis research: strategies for advancing the cognitive and clinical neuroscience of hypnosis. Neurosci Conscious. 2017;3(1). and, more recently, through VR.

Virtual Reality

The idea of immersing a human being in a virtual environment is difficult to date, but the American film director Morton Heilig was one of the first to attempt to put it into practice. In 1955, he designed a multisensory system intended to give the experience of being “in the movie”. Seven years later, he presented a working prototype, the Sensorama. The Sensorama experience simulated a motorcycle ride through an urban environment. This electromechanical system looked like an arcade game. It consisted of a chair that vibrated to simulate movements, a stereoscopic screen with a wide-angle view and stereo speakers. It included a fan to recreate the effect of the wind and scents were released to replicate the smell of motorbike exhaust. However, investors were not convinced by the Sensorama and it never made it on to the market (Figure 2).

The term “Virtual Reality” was coined in the mid-1980s by Jaron Lanier, the founder of VPL Research, a computer hardware company that had started to develop equipment specifically for virtual reality, such as glasses and gloves.

The years 1980 and 1989 marked a golden age in this field. Advances in optic devices went hand in hand with projects for haptic systems and other instruments that allowed the user to experience the virtual space. At NASA’s Ames research centre, one example developed in the mid-1980s was the Virtual Interface Environment Workstation (VIEW) (Figure 3), combining a head-mounted device and gloves to enable haptic interaction.

Today’s virtual reality equipment owes a great deal to the pioneering inventors of the past six decades, who paved the way for the high quality and low-cost devices that are easy to find in the current market. Since it was first developed over 50 years ago, virtual reality has been continually improving, advancing at an exponential rate over the past few years (Figure 4).

Immersion, a sense of presence and embodiment: the process of Virtual Reality

Virtual reality (VR) is generating a growing interest because of its outstanding ability to immerse its users in artificial environments. The work of Riva et al. (2019) [5] Riva G, Wiederhold BK, Mantovani F. Neuroscience of Virtual Reality: From Virtual Exposure to Embodied Medicine. Cyberpsychol Behav Soc Netw. 2019;22(1):82-96. has shown that immersion in VR is closely linked to the activation of the brain’s perceptual mechanisms such as vision, hearing, and in some cases, touch. This synchronised sensory stimulation creates a coherent multisensory experience, inducing a state of immersion in which the user finds themselves psychologically absorbed in the virtual environment (Figures 5 and 6). Elsewhere, Slater and Sanchez-Vives’s research (2016) [28] Slater M, Sanchez-Vives, Maria. Enhancing Our Lives with Immersive Virtual Reality. Frontiers in Robotics and AI. 2016;3 has highlighted the crucial role of sensorimotor correspondence in the immersion process, emphasising the idea that when the user perceives their behaviour to cause an immediate action in response this reinforces the illusion of reality. These psychological phenomena, the willing suspension of disbelief and the effect of presence, contribute to the extent of the immersive experience in virtual reality [29] Biocca F, & Delaney, B. . Immersive virtual reality technology. Lawrence Erlbaum Associates, Inc (1995):(pp. 57–124).. In this way, the combination of sensory synchronisation, sensorimotor correspondence and perceptual illusions go a long way to explaining the unique ability that virtual reality has to fully immerse individuals in artificial environments.

The sense of presence and immersion in virtual reality (VR) form a key field of study in cognitive psychology, bringing to light the complex mechanisms that underlie the user’s experience. The work of Witmer and Singer (1998) [30] Witmer BG, & Singer, M. J. . Measuring presence in virtual environments: A presence questionnaire. Presence: Teleoperators and Virtual Environments, . (1998);7(3):225–240. laid the conceptual foundations by defining presence as the subjective perception of being physically present in a virtual environment, while being aware that this space is artificial. This illusion of presence is closely linked to factors of perception and cognition, as explained by Sanchez-Vives and Slater (2005) [31] Sanchez-Vives MV, Slater M. From presence to consciousness through virtual reality. Nat Rev Neurosci. 2005;6(4):332-339., who emphasised the importance of sensorimotor correspondence between the user’s actions and the responses generated by the virtual reality system. The work of Biocca and Delaney (1995) [29] Biocca F, & Delaney, B. . Immersive virtual reality technology. Lawrence Erlbaum Associates, Inc (1995):(pp. 57–124). also foregrounds the impact of sensory synchronisation on the sense of presence, emphasising that concordance between visual, auditory and, in some cases, haptic sensory stimuli plays a key role in creating an immersive experience. Furthermore, the theory of embodied cognition (Varela et al., 1991) [32] Varela FJ, Thompson, E., & Rosch, E. . The embodied mind: Cognitive science and human experience. The MIT Press. (1991) suggests that when the user interacts directly with the virtual environment this reinforces the sense of being fully immersed, which underscores the importance of motor engagement in building a sense of presence in VR. If we integrate these concepts from cognitive psychology, an understanding of the sense of presence and immersion in virtual reality takes shape as a delicate balance between sensory perception, motor interaction and the awareness that the environment is artificial. It is worth noting that these studies have generally looked at virtual reality environments displayed on 2D screens, and not usually at headsets. As visualisation devices have improved, this naturally reinforces the process of immersion. Today we can much more readily refer to immersive VR.

Hypnosis in Virtual Reality

Scientific evidence to support hypnosis as a viable pain management strategy has mounted up over the past two decades [33] Montgomery GH, DuHamel KN, Redd WH. A meta-analysis of hypnotically induced analgesia: how effective is hypnosis? Int J Clin Exp Hypn. 2000;48(2):138-153.. However, widespread application has been held back by factors such as the advanced expertise, time and effort required by clinicians to provide hypnosis, and the cognitive effort required of patients to commit to it.

Practically speaking, significant in-depth training of care providers would be needed for hypnosis to become an effective pain management modality. Hypnotherapy training is not currently offered in medical schools or even in higher education psychology programmes. Another reason is that administering hypnosis takes more time and effort than giving a pain-relieving pill or injection. The fact that training, skills and patience are required to administer hypnosis makes it difficult to implement in medical centres where the pace is often fast and the clinician’s time is in great demand.

Finally, in an acute care context, the attention and cognitive effort that is required to undergo hypnosis may exceed what is possible for these patients, who are often under the influence of opiate drugs and benzodiazepines. Making hypnosis a standard care offering in these kinds of environments is a challenge.

Over the past 25 years, researchers have been studying the ways in which hypnosis could be made more standardised and more accessible. A handful of studies have looked at whether using audio cassettes is an effective method of providing a hypnotherapy intervention [34] Johnson LS, Wiese KF. Live versus tape-recorded assessments of hypnotic responsiveness in pain-control patients. Int J Clin Exp Hypn. 1979;27(2):74-84.. The results of these studies have proven to be mixed, leaving us to conclude that hypnosis delivered by audio cassette is more effective than an absence of treatment, but less effective than when delivered by a hypnotherapist. Grant and Nash (1995) [35] Grant CD NM. The computer-assisted hypnosis scale: standardization and norming of a computeradministered measure of hypnotic ability. Psychological Assessment 1995;7:49–58. were the first to use computer-assisted hypnosis as a behavioural measure to assess hypnotic ability. This involved a digital voice guiding subjects through a procedure that the software adapted in response to their unique reactions. However, this technique used a conventional 2D screen, so patients were required to focus their attention on a computer screen meaning they were susceptible to distractions that would likely appear in their environment.

Our goal, in developing hypnosis in virtual reality, is to use three-dimensional and immersive VR technology to guide the patient through the steps used when hypnosis is induced through an interpersonal process. The virtual reality system replaces most of the stimuli that the patient would otherwise endeavour to imagine in response to the therapist’s verbal prompts.

Using VR to trigger the hypnotic trance state means that the effects of each one potentiate the other. Used while the patient is under sedation induced by the anaesthesia team in the pre-operative phase, the beneficial effect on the stress component and related peri-operative and post-operative parameters can be measured. The value lies in improving the patient’s environment when they are sedated to reduce the impact of stress and pain on them and on their surgical outcome (Figure 7).

Use of Virtual Reality for patients

VR has been used in many different clinical contexts to help to treat anxiety disorders, control pain, support physiotherapy and to distract patients during wound care [36] Malloy KM, Milling LS. The effectiveness of virtual reality distraction for pain reduction: a systematic review. Clin Psychol Rev. 2010;30(8):1011-1018. (Figure 8). For example, VR in conjunction with medications is an effective strategy for pain reduction when changing bandages in severe burns [37] Carrougher GJ, Hoffman HG, Nakamura D, et al. The effect of virtual reality on pain and range of motion in adults with burn injuries. J Burn Care Res. 2009;30(5):785-791.. It also reduces pain and provides a positive distraction during routine procedures like fitting IV lines [38] Gold JI, Kim SH, Kant AJ, Joseph MH, Rizzo AS. Effectiveness of virtual reality for pediatric pain distraction during i.v. placement. Cyberpsychol Behav. 2006;9(2):207-212. and dental procedures [39] Furman E, Jasinevicius TR, Bissada NF, Victoroff KZ, Skillicorn R, Buchner M. Virtual reality distraction for pain control during periodontal scaling and root planing procedures. J Am Dent Assoc. 2009;140(12):1508-1516.. Other studies have found that VR can help to manage chronic pain, such as in complex regional pain syndrome and [40] Solca M, Ronchi R, Bello-Ruiz J, et al. Heartbeat-enhanced immersive virtual reality to treat complex regional pain syndrome. Neurology. 2018;91(5):e479-e489. chronic neck pain [41] Sarig-Bahat H, Weiss PL, Laufer Y. Neck pain assessment in a virtual environment. Spine (Phila Pa 1976). 2010;35(4):E105-112.. By stimulating the visual and auditory senses [42] Pozeg P, Palluel E, Ronchi R, et al. Virtual reality improves embodiment and neuropathic pain caused by spinal cord injury. Neurology. 2017;89(18):1894-1903., VR acts as an active distraction that can lessen the user’s processing of nociceptive stimuli [43] Li A, Montano Z, Chen VJ, Gold JI. Virtual reality and pain management: current trends and future directions. Pain Manag. 2011;1(2):147-157.. The effective “distraction” strategy involves a phenomenon of disembodiment, inducing a sense of being distanced from the painful body.

The introduction of VR has led to numerous disorders being treated with immersive therapeutic applications. Exposure therapy used in psychiatry is one example. This treatment strategy involves a patient being gradually confronted with the source of their trauma to help them little by little to adopt a new and more constructive behaviour [44] Lognoul M, Nasello J, Triffaux JM. [Virtual reality exposure therapy for post-traumatic stress disorders, obsessive-compulsive disorders and anxiety disorders: Indications, added value and limitations]. Encephale. 2020.. In this area, VR has shown results in the treatment of phobias (flying, driving, heights, spiders, etc.)[45] Mitrousia V, Giotakos O. [Virtual reality therapy in anxiety disorders]. Psychiatriki. 2016;27(4):276-286.. Another promising potential use is as support for physical rehabilitation in patients who have lost motor control. VR could hypothetically open up an enhanced level of reintegration in neurodegenerative or acute pathologies, such as stroke and traumatic injuries [46], Maresca G, Maggio MG, Buda A, et al. A novel use of virtual reality in the treatment of cognitive and motor deficit in spinal cord injury: A case report. Medicine (Baltimore). 2018;97(50):e13559.[47] Keshner EA. Virtual reality and physical rehabilitation: a new toy or a new research and rehabilitation tool? J Neuroeng Rehabil. 2004;1(1):8.. The virtual scenario improves sensory return in the central nervous system, involving changes in synaptic plasticity and as a result reinforcing the acquiring of motor skills and rehabilitation. In fact, platforms for rehabilitation in altered cognitive function or recovery after traumatic brain injury have recently been set up [48] B.Chen TRCSNK. Immersion of virtual reality for rehabilitation. Applied Ergonomics. May 2018;69:153-161.. Another successful medical application for VR has been the demonstration by Dunn et al of its ability to reduce phantom limb pain in people living with amputation or paraplegia [49] Dunn J, Yeo E, Moghaddampour P, Chau B, Humbert S. Virtual and augmented reality in the treatment of phantom limb pain: A literature review. NeuroRehabilitation. 2017;40(4):595-601..

Discussion conclusion

The key feature of VR is that it is capable of producing a sense of immersion. The ability to concentrate and heighten attention is a useful tool in medicine, especially when addressing anxiety and pain. It offers highly effective “gate control”. There is already evidence to support a number of therapies like hypnosis that use distraction of attention. We can now consider the possibility of potentiating the effect of these therapies by using them in conjunction with VR.

However, as with any new system, VR technology has its limitations. These limitations are broadly technical, with software still in development and sometimes too complex to be easily used and financially accessible. There is also a dissonance felt between actual and “false” reality, which could lead to poor adherence in some populations, such as older people. Ultimately, VR is still delivered through a screen, with all the constraints that this implies and the associated emerging pathologies caused by overexposure and proximity to artificial light.

In a hospital environment, pain and anxiety predominate but there is only so much human care can offer in terms of available staff and their time to dedicate to each patient. In situations when human suffering makes care difficult, VR can be a powerful solution and an important tool in the treatment arsenal for managing patients’ pain and anxiety.