Effectiveness and reliability of hypnosis in stereotaxy: a randomized study

Abstract

Background: Patients suffering from Parkinson's disease (PD) may experience pain during stereotactic frame (SF) fixation in deep brain stimulation (DBS). We assessed the role of hypnosis during the SF fixation in PD patients undergoing awake bilateral subthalamic nucleus (STN) DBS.

Methods: N = 19 patients were included (N = 13 males, mean age 63 years; N = 10 allocated to the hypnosis and N = 9 allocated to the control groups). Patients were randomly assigned to the interventional (hypnosis and local anesthesia) or non-interventional (local anesthesia only) groups. The primary outcome was the pain perceived (the visual analogue scale (VAS)). Secondary outcomes were stress, anxiety, and depression, as measured by the perceived stress scale (PSS) and hospital anxiety and depression scale (HADS). Procedural distress was measured using the peritraumatic distress inventory (PDI-13).

Results: In the hypnosis group, VAS_mean was 5.6 ± 2.1, versus 6.4 ± 1.2 in the control group (p = 0.31). Intervention and control groups reported similar VAS_max scores (7.6 ± 2.1 versus 8.6 ± 1.6 (p = 0.28), respectively). Both groups had similar HADS scores (6.2 ± 4.3 versus 6.7 ± 1.92, p = 0.72 (HADSa) and 6.7 ± 4.2 versus 7.7 ± 3, p = 0.58 (HADSd)), so were the PSS scores (26.1 ± 6.3 versus 25.1 ± 7, p = 0.75). Evolutions of VAS_mean (R² = 0.93, 95% CI [0.2245, 1.825], p = 0.03) and PDI-13 scores (R² = 0.94, 95% CI [1.006, 6.279], p = 0.02) significantly differ over follow-up with patients in the hypnosis groups showing lower scores.

Conclusion: In this unblinded, randomized study, hypnosis does not influence pain, anxiety, and distress during awake SF fixation but modulates pain memory over time and may prevent the integration of awake painful procedures as a bad experience into the autobiographical memory of patients suffering from PD. A randomized controlled study with more data is necessary to confirm our findings.

Trial registration: ClinicalTrials.gov NCT03074422.

Keywords: Deep brain stimulation; Hypnosis; Pain; Parkinson’s disease.

Fig. 1

Summary of screening, inclusion, intervention, and follow-up milestones of the study. Patients suffering from Parkinson’s disease were screened during the regular multidisciplinary assessment for deep brain stimulation involving neurologists and neurosurgeons. Study inclusion was achieved 1 month before surgery. Patients were unblindedly randomized into the hypnosis or into the control group the day prior to the surgery. Procedural pain and distress were assessed after the mounting of the stereotaxic frame as well as at 6- and 12-month follow-up, while anxiety and stress were measured before the surgery as well as at 6- and 12-month follow-up. PD, Parkinson’s disease; DBS, deep brain stimulation; STN, subthalamic nucleus; M, month; HAD, hospital anxiety and depression scale; PSS, perceived stress scale; VAS, visual analogue scale; PDI-13, peritraumatic distress inventory-13 items; PCLS, post-traumatic stress disorder checklist state

Fig. 2

Forty-five min prior to frame mounting, four patches of prilocaïne/lidocaïne (5%) were applied to the skin of the patient, at the level of the fixation points of the Leksell headframe

Fig. 3

Typical setup during a hypnosis session prior to a deep brain stimulation surgery for Parkinson’s disease. The hypnotherapist (A) faces the patient (B). Behind the patient, one surgeon (C) mounts the stereotaxic frame. The other surgeon (D) stands on the side of the patient and holds the frame, ensuring that the head is straight. During the session, surgeons do not speak while the patient and the hypnotherapist communicate

Fig. 4

Study flowchart summarizing randomization in both groups and further distribution of the study population throughout the study period. There were no cross-overs. One patient was lost of follow-up in the intervention group, while three patients did not attend the 6-month assessments and one patient did not respond to the 1-year questionnaires

Fig. 5

Evolutions of VAS_mean (left) and PDI-13 (right) scores in both cohorts throughout the study period. Regarding VAS_mean, both cohorts showed an overall reduction of pain quotation during follow-up, which was more there was a pattern of reduction of scores in both cohorts, which was significantly more marked in patients who received hypnosis. Regarding PDI-13 scores, both cohorts showed increased scores after the procedure, which was significantly higher in the control group. VAS, visual analogue scale; PDI, peritraumatic distress inventory