Surgeons have conducted placebo-controlled double-blind investigations to determine the value of some surgical procedures.7,33,35 In these studies, results of real operations were compared with those from sham surgeries that matched the operative experience, including anesthesia and skin incision. In some cases, the sham procedures invaded deeper tissues.7,33,35 After consenting to participate, subjects and postoperative evaluators were blind to the true nature of the procedure.7,33,35 Although some raise ethical questions about performing sham operations,4,21,27,31,41,42 the research often yields startling findings.7,35 As a result, some procedures have been eliminated from the surgical lexicon, thereby confirming the value of placebo procedures in surgical research.7,35
Joan Cassell, an anthropologist, spent time following a surgeon during his day-to-day activities.5 She reported modern surgical procedures shared certain features with the activities of traditional healers (shamans).5 She suggested the ritualistic features of the surgical experience, and how surgeons possess a charismatic sense of healing capacity to help effectuate a cure.5
Cassell emphasized the mystical features of a surgeon's interaction with his or her patient without delving into the ways that the entire surgical experience enhanced suggestibility.5 It could be argued many modern operations depend on the placebo effect for a favorable outcome.
Shamanic healers clearly, but perhaps unknowingly, depend on suggestibility and the placebo effect as much as natural healing. Shamans believe their actions, which often involve trance-like journeys to the netherworld, animal transformations, and other supernatural processes, ensure the exorcism of malevolent demons and encourage the favorable response of gods and spirits.12,23,24,26,50 To achieve these ends, the shaman performs many rituals and engages in certain activities that enhance. Likewise, the shaman's belief system bolsters and enhances the subject's sense that something beneficial occurred during the ritual.43
Considering how prominent the placebo effect is in modern therapeutics when studied with double-blind methods, I analyzed the elements of a surgical encounter to see how they might influence suggestibility, independent from their presumed medical purpose. There are reasons for each step of modern surgical procedures; however, many measures have an uncanny resemblance to features of shamanistic practices. Surgeons and shamans can enhance suggestibility, which contributes to a favorable result.
I consider shamanistic practices and the modern surgical experience as a sequence of events arranged in a specific order to achieve an end. Each step has a specific sequence and purpose. Although it could be argued that every measure in a surgical encounter is designed to reduce complications, diminish pain, and enhance healing, a shaman would correctly point out that each step in his or her ritual also has a specific purpose.
Journal to the Healing Place
Although shamans usually conduct their rituals in the subject's abode, they often will set apart a specific space to conduct the ceremony.23 By so doing, the subject becomes somewhat disoriented by being in an unfamiliar environment. Likewise, patients leave familiar surroundings and travel to a specific space (hospital or surgical center) to have the procedure. The patient interacts with educated individuals who, by their mere presence, reinforce the suggestion that the procedure can cure. As with a shaman's ritual space, the unfamiliar and utilitarian features of a surgical facility enhance suggestibility.
Fasting induces a state of hypoglycemia, which alters consciousness.15 Shamans often fast for days to induce the trance-like state necessary for traveling to the spirit world.3 Prolonged dancing has the same effect. Likewise, nulla per os after midnight not only achieves the aim of emptying gastric contents, but may induce hypoglycemia by eliminating the usual morning carbohydrate infusion, leading to light-headedness. The patient becomes in an altered sensory state, making them more prone to the influence of suggestion.
Donning of Ritual Garb
Wearing special apparel designed specifically for ceremonial purposes is a hallmark of human existence. For example, primitive cultures us ceremonial clothing to enhance the ritual experience because, “Costumes play an important part in the trance state.”23
Similarly, a patient must strip off their clothes and put on a loose-fitting garment, which immediately designates them a patient in an unfamiliar environment. Regardless of one's status in the community, becoming a hospitalized patient places the individual in a constrained environment where freedom of action is greatly inhibited. This social disorientation likely enhances suggestibility.
Ingestion of Psychotropic Substances
Many shamanistic rituals involve ingesting psychotropic substances: Native American practitioners have used psychedelic mushrooms and peyote buttons for millennia.9,12,48 Fermented beverages (eg, mead, beer, wine) also result in a mind-altering experience that may serve to enhance suggestibility. The surgical ritual involves administering premedication designed to reduce anxiety and ease administration of more powerful agents.
Anointment with Purifying Liquid
Shamanistic purification rituals often include a kind of spiritual cleansing accomplished by anointment with oil, water, or animal grease.43,44,50 Preoperative skin preparation by shaving and applying a povidone-iodine solution serves a logical purpose, as do all other steps in the surgical ritual. However, the impact of seeing one's hairless, orange-colored limb, so dissimilar from ordinary experience, may also contribute to changes in suggestibility.
Encounter with the Masked Healer
The remarkable variety of masks and costumes used in rituals throughout the world attest to the value of physical transformation. In describing shamanistic practices of Greenland, Jakobsen described how “masks were often used in the house-games (uaajeertut) when they tried to represent the spirit of the angakut.”23 Cassell describes the modern surgical experience as having similar traits: “in this ritual drama, masked surgeons behave heroically, in a special, secluded ritual space … wearing a distinctive costume that obscures the face and hair . . .”5
Inhalation of Stupefactive Vapors
Few actions more rapidly and more completely alter the senses more than absorbing consciousness-altering substances directly into pulmonary circulation, as the very next heartbeat sends the chemicals directly to the brain. Shamans have, since time immemorial, used burning poppy opiates, tobacco smoke, smoldering hemp, and many other substances to produce a trance-like state, which, no doubt, increased suggestibility in themselves and their witnesses.3,9,22,26,48 If a shaman can, by the use of such substances, transform into an animal and cross into the spirit world in front of others who also have been exposed to such vapors, then the human capacity for suggestibility is astounding.
Moderate anesthetic agents rapidly induce unconsciousness that likely renders the subject immune to suggestion, although some anesthesiologists believe patients hear and remember what is said during unconsciousness. Experienced surgeons make it a point to go to the recovery room as their patients emerge from stupor, but before they'recapable of verbal response, to reinforce “the operation was a success,” or “everything will be fine and your pain will be gone.” Clearly, posthypnotic suggestion may help in this situation.
Central Ritual Activity
Surgeons and shamans perform procedures designed to bring about a cure using elaborate preparations and procedures. I group these activities into three distinct categories: extracorporeal, surface, and penetrative.
Many central ritual activities are extracorporeal as they do not involve physical contact with the subject; these include animal slaughter, prayer, sand painting, and the shaman trance-vision journey to the spirit world. Each of these activities follows prescribed patterns based on the practitioner's belief system.30,49 Prayers to specific deities, saints, or spirits accomplish the same thing, but in our culture, people do not pray to a rain god, the patron saint of travelers, or to the deity of volcanoes to provide medical treatment. However, in other cultures, failure to evoke a cure is blamed on wrongly directed, inadequate, insincere, or impure prayers.17,24,43
A sand painting consist of a precisely sequenced series of symbols having meaning to individuals who have spent at least a decade learning how to interpret them.36 Every figure, stroke, and dot in a sand painting exists for a purpose, one easily explained by the practitioner. Navajo sand paintings represent the dynamics of a struggle between the forces of good and evil affecting a desired outcome.36 The sand painting clearly impacts the subject but has the greatest effect on the shaman, who feels a sense of potency conveyed by the symbols used to dispel evil.36
The modern surgical ritual has a sand painting equivalent: the patient consent document. It also consists of a precisely ordered sequence of symbols incomprehensible except to those who have spent at least a decade learning how to interpret the symbols (letters). As with sand paintings, its greatest influence is on the practitioner, who senses empowerment offered by the document. Only under the most extraordinary circumstances would a Navajo shaman or orthopaedic surgeon perform the ritual without a proper sand painting or consent document, respectively. However, similar to sand paintings, consent forms do not always work successfully.
Most healing rituals go beyond words and diagrams and involve physical contact between the practitioner and subject. The relaxed sense one experiences after a massage is more mental than physical. Entire professions (eg, chiropractic) rely on contact therapy, the effect enhanced by thrust maneuvers designed to elicit a pop from a joint. For surgeons, therapeutic touching consists of hand holding, a pat on the back, and other elements of perioperative contact that convey a caring attitude to the patient which enhances suggestibility.
Penetration of the body's cutaneous envelope defines the most serious invasion of bodily space and sets up the subject to a level of suggestibility unobtainable by other means.1
Many cultures incorporate bloodletting during rituals.19,45 A Mayan king would pierce the dorsal vein of his penis using a stingray spine, spilling blood onto various objects, thereby sanctifying them and him.45 For centuries, physicians practiced bloodletting in an attempt to restore balance to the four humors that served as life's vital fluids. Removing one or two pints of blood often results in faintness (caused by hypovolemia), an altered state of consciousness that may, along with the other measures described in this article, increase suggestibility.
The modern surgical experience starts with an intravenous (IV) needle insertion. The patient may watch his or her vital fluid flow backward a couple of inches into a transparent IV tube. The sight of one's own blood makes some people feel queasy or faint; both are altered states of consciousness that may affect suggestibility.
In ancient Mayan civilization, the queen pulled a rope through her tongue.34 Members of certain Native Americans tribes performed a ceremony where wooden pegs were pushed through their chest walls and attached to ropes that then were tossed over a tree limb and attached to heavy weights.12 The ritual tested endurance and will- power by remaining in this position for hours or days while facing the sun.12 The mind was so altered that hallucinogenic visions often occurred without using supplementary drugs.12
Such practices result in an altered state of consciousness, which probably results from the endorphins released in response to pain.30
Having its roots in Eastern cultures, acupuncture also has become popular in certain Western cultures. The practitioner inserts thin needles into specific locations along meridians, which have their origins in ancient Chinese philosophy rather than human anatomy.37,53 Some acupuncturists claim the human ear is formed like an inverted homunculus, with every organ represented by a point on the ear lobe.53 Similarly, Korean hand acupuncture assumes representation of bodily organs and structures on the palmar surface of the hand and digits.46 The middle finger, for example, contains components representing the human face looking very much like a finger puppet.53 Placebo-controlled studies of acupuncture often fail to confirm the claims of acupuncturists11,29,55 but the high placebo value fascinates researchers studying in pain management.11,12,39
Modern operations, although conducted under pain- relieving anesthesia, are hardly painless procedures once the medication has worn off. Pain stimulates the release of natural opioids, likely increasing suggestibility.39 Patients having surgical procedures require strong medication for pain control, which means ingesting more mind-altering substances.
Post Ritual Activity
Certain practices after the central ritual activity enhance the placebo effect. Among certain Native American tribes, sitting in a sweat lodge favorably influenced the outcome.12 We have our own version of the post ritual reinforcement system; physical therapy. Although postoperative physical therapy is essential for obtaining a good result after certain musculoskeletal surgical procedures, it is superfluous after many others. However, constant reinforcement and encouragement combined with therapeutic treatments all emphasize how a favorable outcome depends on the patient's efforts and desire. Patients achieve pain relief by repressing painful afferent neuronal impulses coming from the symptomatic region.
The Laws of Placebo Dynamics
I formulated three definitions for placebo dynamics as a somewhat tongue-in-cheek outline of the placebo effect. First, the more elaborate the ritual, the greater the placebo effect. It is only natural for a subject to believe a complex ritual involving the efforts of several individuals, complete with well-established behavioral patterns, traditional costumes, and other such measures, must provide a cure or people respected in the community would not spend their valuable time performing such activities. Researchers have shown that an injected placebo is more effective than an oral placebo10 and that a placebo acupuncture using a collapsible needle is more effective that a placebo pill.25
Second, the placebo effect is directly proportional to the practitioner's faith in its validity and evident enthusiasm. One simply has to observe practitioners performing the prescribed activities in a belief system foreign to one's own to recognize the validity of this assessment. Sometimes, when watching priests or holy men of a different culture, the observer feels a sense of bemused wonderment that the partaker actually believes his actions somehow influence cosmic and earthly events. Yet remarkably, he creates a self-fulfilling prophecy because he influences other participants who share his belief system.
In a study performed more than three decades ago, Gracely divided physicians into two groups, one being informed that their patients will be receiving placebo patches and the other being told that their patients will get the active ingredient. Patients of the physicians who believed they were giving the active medication did better than patients of the other physicians although, in truth, all patients received placebos.16
Third, the placebo effect is inversely proportional to the subject's skepticism and resistance, squared. Just as it is easy to resist being hypnotized, skepticism about the benefit of a ritual usually nullifies its effectiveness. Jakobsen reported how skepticism destroyed the effectiveness of a shamanistic ritual: “The trance did not occur because non- believers were present and showed disbelief or ridiculed the shaman.”23
Until we understand how symptom amplification or repression occurs, we cannot fathom the remarkable impact of the placebo effect because amplification and repression are closely related. Both rely on the influence that so- called top-down processes have on our awareness of somatic afferent impulses generated in our peripheral nervous system. In other words, our mental state of mind sways our physical response.
Work in the field of attention theory has identified neural pathways active in the enhancement and repression of painful stimuli.17,26,31 Researchers using PET scans have determined areas of the brain activated under the influence of thought and suggestion.20,40 Hofbauer et al20 and Rain- ville et al40 studied the influence of suggestion on hypnotized subjects by immersing their hands in tepid water that the experimenters described as either warm or very hot. They ascertained which regions of the brain responded to the prompting and stimulus.20,40 When repeating the experiment without hypnosis, they observed verbal suggestion was sufficient to produce the observed effect.20,40
Based on PET scan results, Hofbauer et al20 found afferent impulses from the warmed limb arrive at the brain via the spinal cord. In the brain, impulses are divided into two streams, one set going to the somatosensory cortex, which perceives the warmth but does not assign an emotional value to the stimulus. Simultaneously, the other stream of impulses are sent to the anterior cortex of the cingulate gyrus where the unpleasantness of the stimulus is generated. Information from the somatosensory cortex and the cingulate gyrus are integrated, leading to what we experience as pain.
According to Hofbauer et al,20 pain has a sensory- discriminative dimension and an affective-motivational dimension. The affective-motivational dimension influences the way we respond to an afferent sensation.20 This concept forms the core of attention theory, an attempt to explain how we sort through the billions of sensory afferent impulses that bombard our central nervous system every second.
Consider this example of the cingulate gyrus's attention center at work: During the time you've been reading this article, until I call it to your attention, you've been completely unaware of the sensation your buttocks is experiencing against your chair, but as soon as I mention it, you become attentive to the pressure. In fact, if you think about the pressure and concentrate on it, the pressure will soon reveal its tingly quality, and after that, warmth; which, with more concentration and attention actually begins to feel like a hot almost burning pain. Try it. Focus attention on the sensation from your buttocks for a while and see what happens.
If you now think about the pressure your collar is making against your neck, a much softer less uncomfortable pressure, you'll have completely relieved the buttocks discomfort. Conscious thought influences our response to painful stimuli, as does subconscious activity. Pain perception is a biopsychosocial process.2,6,8,32,38,47 The placebo effect may account for a large proportion of the beneficial results reported in surgical series where pain relief is the primary outcome measurement.13,14,28,54,56 Considering how the perioperative ritual can potentiate the placebo effect by enhancing suggestibility, it is not surprising studies using sham operations in a double-blind design refute the efficacy of the procedure. There is no substitute for a sham surgery when investigating the value of a controversial operation.
Although one could argue it makes no difference how an operation works as long as the patient is satisfied with the outcome,51 surgery has certain inherent risks that can be avoided if another noninvasive treatment method proves equally effective.18,42 Therefore, it might be wise to test many elective (ie, discretionary) pain-relieving operations in randomized prospective double-blind studies. Designing such clinical trials will be difficult, because of the ethical issues involved.27,31,41,42,52 Kim et al surveyed clinical researchers of Parkinson's disease about the ethics of sham surgery.27 Although 97% of those responding to the questionnaire believed that sham-controlled surgery was better than unblinded controls for testing, only 22% were comfortable with invading the brain for such studies.27
Institutional Review Boards may be reluctant to authorize studies involving control subjects for sham surgeries. Nevertheless, we have little choice but to scrutinize surgeries where there are doubts about efficacy. Once articles begin to appear in the medical literature about adverse outcomes from surgical procedures of dubious value, the argument for control subjects for sham surgeries becomes easier. The researcher could point out to the Board that the procedure being studied has greater known risk than the sham operation, with the same potential outcome. Therefore, the sham surgery, independent of its place in a research protocol, is morally justified as a potentially safer way to achieve a desired benefit for a patient. Using this argument, the research protocol becomes, in effect, a comparison between two procedures of possible benefit, rather than a placebo-controlled investigation of one operation.
If we as surgeons are unwilling to subject our practices and rituals to scrutiny, than we shouldn't represent ourselves as practitioners of scientific medicine.
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