Mind-body therapies such as mindfulness meditation (MM) are increasingly being studied and applied as legitimate medical therapies. Since becoming popular in the 1970s, MM has been shown to improve psychological states such as anxiety and depression. The scope of MM has expanded in recent years, and MM has been shown to have positive effects on pain, recovery time, and even wound healing after surgery. The number and types of surgery are increasing with the ageing population, and MM has potential as a non-surgical therapy to help hasten recovery, minimise analgesic consumption, and improve overall satisfaction after surgery. Training patients in MM before surgery may be implemented at low cost and up to 24 hours before admission. Given these benefits, complementary mind-body therapies such as MM have potential to improve a patient’s surgical experience and outcomes. Despite the potential benefits, MM is not currently used routinely for patients undergoing surgery. The literature shows that there is a perceived suspicion of the practice’s effectiveness, which appears to hamper its clinical acceptance. Critics cite concerns about patients’ perception of meditation given its religious connotations and whether they would be encouraged to accept MM as a valid therapy. This essay explores the application of MM as a complementary therapy to expedite recovery from surgical admission and concludes that meditation may be as effective as medication in some circumstances.

 

Introduction

“The part can never be well unless the whole is well.” This epithet offered by Plato 2300 years ago refers to the symbiotic relationship between mental and physical health, and has increasingly been embraced by Western society [1]. The concept that psychological state can influence physical well-being has contributed to the acceptance and use of mind-body therapies and motivated research into their health benefits. Recent scientific enquiry has noted diverse benefits of meditation such as reduced anxiety and depression levels, improved cardiac health, heightened immunity, and fewer post-chemotherapy adverse symptoms among cancer patients [2-4]. Researchers have also established a strong link between mind-body therapies and pain attenuation [5]. These findings suggest that these therapies may have potential as treatment for elective surgery inpatients.

With the increased number and types of surgical procedures required by an ageing population, meditation has been proposed as a means of improving post-operative outcomes, particularly after elective surgery [6]. Despite reported benefits and potentially low implementation costs [7], traditional medicine has been slow in adopting these alternatives. Critics remain sceptical of the efficacy and practicality of meditation, whereas advocates suggest that the analgesic qualities indicate clinical potential. To reconcile these opposing views, one must consider the logistical, psychosocial, and therapeutic aspects of meditation in the surgical context.

 

Mindfulness meditation

Meditation is often defined as mental exercises and techniques designed to calm the mind through physiological processes [8-10]. Mindfulness meditation (MM) sometimes referred to as ‘Vipassana practice’ or ‘insight meditation’, was thought to have been conceived by Buddhist scholars over 2000 years ago in India and is inextricably linked with Buddhist theology [11]. It involves cultivating a focused psychological attention to the internal and external experiences occurring in the present moment [12,13]. In practice, MM requires attentiveness to simple physical sensations such as breathing, eating, or sitting. Technical applications of this approach vary. One popular methodology in a clinical setting involves using one’s imagination to mentally scan the entire body for awareness of physical sensations without judgment, beginning with the head and progressing to the toes. This can be used for any duration and in many circumstances. MM may also incorporate ‘guided imagery’ techniques in a clinical context, in which the patient visualises his or her own healing process and affirms thoughts of positivity regarding the management of illness [14].

 

MM as a form of therapy

Despite its origins in antiquity, MM has recently been adopted by Western society [15], and today’s incarnation is mostly secular [16]. One of the first occasions of mindfulness being introduced to Western medicine occurred in 1979 by Kabat-Zinn’s Mindfulness Based Stress Reduction (MBSR) program at the Stress Reduction Clinic at the University of Massachusetts Medical Center [3,17]. The inaugural program described reduced self-reported scores for depression and anxiety in participants with psychological problems [11].

To implement MM as a therapeutic tool, Kabat-Zinn adapted the methodology. He anticipated that the introduction of an alternative medicine, particularly one with religious associations, would be denounced by orthodox medical practitioners as the work of charlatans or mystics [17]. Overcoming this prevailing medical stigma was integral to the wider acceptance of mindfulness today. Accordingly, Kabat-Zinn distinguished MBSR from its religious counterpart by exploring the curative potential of meditation and designed it to be used as a clinical tool that complemented rather than replaced conventional medical therapies.

The scope of clinical mindfulness has expanded greatly with wider acceptance of MM by the wider scientific community. Current programs include mindfulness-based cognitive therapy, acceptance and commitment therapy, and mindfulness-based relapse prevention [18,19]. There are now even smart phone applications, DVDs, and self-help books, which have propelled mindfulness concepts into the public domain.

The acceptance of mindfulness by the medical community is also evidenced by the recent interest in the scientific evaluation of mindfulness as a health promotion tool. For example, in the 2008-09 fiscal year, the US government funded hundreds of studies concerning the clinical applications of various meditative practices, at a cost of US $51 million [17].

 

MM and surgical outcomes

By influencing psychological states, MM may help address post-surgical complications such as pain and reduced functioning [20]. A systematic review of studies that evaluated psychological variables and surgical outcomes found that psychological state strongly correlates with early recovery, although differences in study design restrict the ability to confidently pool results [20]. Psychological factors have also been shown on occasion to be superior predictors of post-operative outcomes than the surgical intervention itself [14]. Despite continued technological innovation, today many patients endure moderate to severe negative post-operative outcomes [21]. For example, up to 40% of patients who undergo elective joint replacement surgery report suboptimal functional improvement, pain relief, and overall satisfaction after their procedure [22]. These issues suggest that there is a need for complementary therapies to support existing therapies in a surgical setting.

Mind-body therapies such as MM are being increasingly evaluated for their effects on post-operative psychological variables. The use of mind-body therapies as a nonpharmacological adjunct has been well studied in cardiac, abdominal, and orthopaedic surgeries [14]. In these contexts, MM is associated with improved levels of pain, anxiety, fatigue, and distress [14]. Reduced systolic blood pressure has been reported during the post-operative period in patients who have practised a guided-imagery protocol [23]. Other benefits include shorter hospital stay and promotion of wound healing in some studies [14,24].

MM has been shown to be useful for reducing reliance on analgesia in the post-operative period and beyond [14]. Analgesia consumption levels can be used as a proxy for pain control. Although analgesic use is essential for promoting surgical recovery, too great a reliance on pharmaceuticals increases the risk of adverse side effects such as nausea, respiratory depression, and lethargy [25]. Some analgesics can also predispose to long-term dependency if their use is not appropriately stewarded. Palmaro et al. [26] observed that one-third of patients undergoing orthopaedic surgery for carpal tunnel syndrome had persistent and increased consumption of anti-neuropathic and/or opioid analgesics for more than two months after surgery. Among this population, psychiatric disorders and subjective levels of pre-operative pain explained this increased use [26]. MM may positively affect these two variables and reduce medication use. An estimated 234.2 million surgeries are performed worldwide each year, many of these necessitating pain medications [27]. It would therefore make fiscal sense to reduce the amount of pharmaceuticals required after surgery through the use of nonpharmacological therapies such as MM.

 

Proposed mechanisms to explain the effects of MM on post-operative pain

Meditative practice has been shown to change brain structure and function [28]. These effects may be seen both immediately and from chronic practice as demonstrated via brain imaging modalities such as fMRI, SPECT and PET [28]. Firstly, the prefrontal cortex (PFC) is intensely active during meditation, specifically the lateral prefrontal regions [28,29]. The ventromedial areas of the PFC are responsible for the affective integration of sensory input, whilst the posterolateral regions are concerned with sensory appraisal without self-referential value [29]. It is proposed that a neuronal shift away from the ventromedial prefrontal regions to the posterolateral centres supports a more self-detached analysis of interoceptive and exteroceptive sensory events [29]. Secondly, additional neural correlates such as modulation of the limbic system contribute to meditative effects [28]. MM practice has been shown to reduce the activity of the amygdala, and broader limbic structures concerned with emotional reactions [28].  For example, after eight weeks of an MM intervention, arterial spin labelling functional MRI showed neuroarchitectural changes such as increasing grey matter concentration within the left hippocampus an amygdala [16]. These regions are associated with emotional regulation, which may account for reduced anxiety and improved coping reported after programs of a similar duration [30]. In addition to this, MM has been posited to exert influence on the hypothalamus, which by extension shifts autonomic nervous system function towards increased parasympathetic activity [28]. This hypothesis attempts to explain physiological reductions in heart rates, blood pressure and serum cortisol levels which all evidence relaxation experienced during MM [28].

Another potential benefit of MM as a surgical therapy is pain modulation. However the exact mechanisms through which MM regulates pain are unknown [3,31]. Zeidan et al. [5] suggested MM can attenuate post-operative pain, reporting a 40% reduction in pain intensity and 57% reduction in pain unpleasantness following mindfulness intervention in a laboratory setting. The authors posited that this phenomenon results from synergistic interactions of improved attentional control, expectation modulation, and a placebo effect. By exerting attentional control on physical sensations other than discomfort, MM is thought to dampen the saliency of nociceptive stimuli.

Although this explanation seems to be reductive at face value, it is consistent with knowledge about complex neurobiology. The influence of MM on neurological pain-modulating networks is only now being explored. The cognitive inhibition of pain has traditionally been attributed to opioidergic mechanisms [32,33]. This model proposes that endogenous opioids are secreted by regions of the brain with an abundance of opioid receptors [33] and that these natural opioids elicit analgesic effects. Opioid receptors are found in high concentrations in the anterior cingulate cortex, orbitofrontal cortex (OFC), and insula [34]. Pain relief attributed to a placebo effect, conditioned pain modulation, and attentional control mechanisms such as those involved in MM rely on opioidergic pain relief [35-37]. These analgesic effects can be reversed after administration with opioid antagonists such as naloxone [34]. Imaging studies have shown that MM-induced analgesia is associated with increased activation in these regions of the brain [34]. This suggests that opioidergic mechanisms may account for some of the analgesic effects associated with MM.

Pain attenuation by MM may be supplemented by non-opioidergic mechanisms because opioidergic and non-opioidergic brain regions work synergistically. In MM, the OFC projects synapses to the thalamic reticular nuclei (TRN) which, via further projections exerts inhibitory control over the thalamus, an area considered to be the ‘gatekeeper’ through which all sensory information must pass [38]. When the TRN is active (either through the OFC or distinct mechanisms) ascending information such as nociception may be filtered from triggering conscious awareness [38]. MM therapy responses might therefore be mediated by the interaction between the OFC and the TRN, which appears to inhibit nociception from reaching the conscious part of the brain, the cerebral cortex. Self-facilitated pain modulatory systems seem to be engaged by non-evaluative recognition of an unpleasant physical sensation such as nociception [38]. Pain reduction experienced during MM is also associated with thalamic deactivation, which suggests a pain-gating effect may be exerted by the limbic system [5]. This suggests that nociception is influenced by the complex interaction of expectations, emotions, and cognitive appraisals, and may be modulated by the meta-cognitive task of focusing on the present moment [5].

 

Delivery of MM therapy to elective surgical patients

MM-based interventions vary in format and administration. Group mindfulness interventions are often preferable in clinical and research settings, and have been shown to expedite improved socialisation, program participation, and skill acquisition [14].

Group therapy with a set number of sessions of prescribed length may be more cost-effective than individual one-to-one interventions [14]. In group formats, a health professional such as a psychologist, physician or nurse instructs participants and distributes supporting material such as books and audiotapes to reinforce the program rationale and encourage independent practice outside standardised sessions.

It may not be practical to offer group sessions for patients undergoing elective surgery because of the nature of elective admissions, which are typically non-emergency procedures and can be delayed or rescheduled at short notice. Patients requiring more urgent surgery would not have sufficient advance notice to begin preoperative group therapy. Therefore, viable program methodologies should be flexible in terms of participant admission or delivered on an individualised basis as part of pre-operative patient care.

Personalised instruction or a single session with a psychologist can be tailored to the patient’s level of comprehension. Patients could also be given the opportunity for follow-up sessions to consolidate skills learned before admission.

Regardless of the mode of delivery, the rationale, advantages, and disadvantages of MM should be explained to the patient before surgery. The patient’s cognitive capacity and psychological state should be assessed by the physician or psychologist to evaluate his or her suitability for MM intervention and provide baseline psychological scores for comparison.

The benefits of regular MM practice in clinical practice have been well documented, and these skills can be consolidated for life [17]. In the context of pre-operative MM programs, optimum duration and timing of MM programs should be considered. The MBSR program developed by Kabat-Zinn [13] spans an 8-week course involving a 20-minute intervention each day. Many clinical programs use a similar program design, which has shown to be adequate to elicit desired benefits [17].

However it does not seem to be necessary for pre-operative programs to be as long as eight weeks to elicit desired effects. MM therapy given for the first time 24 hours before an operation has been shown to be beneficial. For example, Manyande et al. [39] reported reduced scores for post-operative pain and distress, and ward analgesic consumption for surgical patients given a 15-minute audio recording 1 day before elective abdominal surgery. Other studies have reported similar results [18,34,40]. Thus, although the benefits of MM are generally associated with regular practice (which may discourage some from taking up the practice), these findings imply that MM therapy involving short mental training may produce benefits even when undertaken in the days before surgery.

 

Limitations to MM therapy in the surgical context

There are potential limitations to MM as a pre- and post-operative therapy for surgical patients. The success of MM programs can be limited by surgery type and patient attributes, such as physical or cognitive impairment [14]. The stress associated with a hospital admission and surgery may impair a patient’s ability to learn a new skill such as MM [41].

Implementation of standardised programs across healthcare providers may require additional funding, development of standardised educational material, and targeted training for healthcare professionals. Estimates of the resources needed would also vary according to differences between practices and institutional infrastructure. However, the cost of implementing MM programs may be recovered at least in part by improved recovery, reduced length of stay, reduced complication rates and reduced analgesic consumption [14,24,39,42]. Further cost-benefit analysis of MM programs for surgical patients may be warranted to better understand the organisational fiscal advantages associated with the use of MM therapies.

The effect size of MM intervention on post-operative outcomes has been subject to debate. Some studies investigating the use of pre-operative mind-body therapies in the surgical context failed to establish changes to post-operative outcomes such as pain and duration of hospital stay [14]. For example, Scott and Clum [43] observed no significant effects of treatments on outcome measures such pain, anxiety and analgesic intake after an attentional control regimen initiated 24hr prior to abdominal surgery. Other studies described mixed outcomes of such protocols [14,39]. It has been suggested that heterogeneity in study design and differences in the surgical context in which they are examined restrict generalizations being formed into the effectiveness of individual protocol design [14]. This is additionally hampered by fluid definitions of ‘mind-body therapies’ and noted methodological flaws consistent throughout much of existing literature, such as reduced sample size, inadequate controls and insufficient study duration [14,17]. Additionally, it is difficult to account for the influence of external factors on broader research outcomes. Factors such as insurance coverage may exert control on measures such as duration of hospital stay which may distort findings [14]. Further research may need to be conducted to reconcile these considerations and establish the clinical scope of MM.

It is unknown how receptive patients would be to learning MM around the time of surgery. Patients may be sceptical of or uninformed about mind-body therapies [17]. It is also unclear if the religious connotations associated with MM would promote or hinder patient participation [17]. Some patients may be discouraged by anything resembling a religious practice or indeed the opposite may be true [17]. Such phenomena may be subject to many individual patient factors and could be difficult to predict in the absence of empirical data. Future enquiry may seek to better understand the influence of individual patient preferences and values on MM adherence. It may be reasoned that patient education and evidence-based practice could also help dispel misconceptions about MM therapy and foster its adoption amongst the wider community, but research would be needed to corroborate this.

 

Conclusion

Since its adoption by Western society, MM has become increasingly used as a clinical tool. With an ageing population and increased demand for surgical interventions, complementary therapies such as MM should be considered. In the surgical setting, MM may reduce pain, anxiety, and distress, improve contentment, psychological state, and recovery time, and could decrease the need for high levels of medication and the risks associated with polypharmacy. Beyond its physiological effects, MM may also benefit those seeking relief from mental and physical stresses encountered during their hospital admission. Further research and development are needed to establish viable standardised treatment programs. Despite the mixed opinions about MM, it is likely that future medical practitioners will regard MM as a powerful therapeutic option in addition to its pharmacological counterpart.

 

Conflict of interest

None.

 

Acknowledgements

The authors wish to acknowledge Laurel Mackinnon, PhD, ELS, and Sharon Johnatty, PhD, for their invaluable assistance in editing this article.

 

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