Paediatric Sickle Cell Disease Pain and Biofeedback

Sickle Cell Disease (SCD) is caused by a faulty gene that affects how red blood cells develop. Unusually shaped red blood cells can cause problems because they don't live as long as healthy blood cells and they can become stuck in blood vessels. 

One of the main symptoms of SCD are painful episodes called sickle cell crises, which can be very severe. The blood cells can block blood flow through tiny blood vessels to the chest, abdomen and joints. Pain can also occur in the bones.

The pain varies in intensity and can last for a few hours to a few weeks. Some people have only a few pain episodes. Others have a dozen or more crises a year. If a crisis is severe enough, hopitalisation might need to be required.  Some adolescents and adults with sickle cell anemia also have chronic pain, which can result from bone and joint damage, ulcers and other causes.

These vaso-occlusive crises can result in a vicious cycle in which the occlusion causes pain, activating the autonomic nervous system. Arousal of the autonomic nervous system produces increased muscle tension and more vascular constriction, further restricting blood flow to the area of the occlusion. If this cycle can be interrupted by pharmacologic or other interventions, blood flow may then increase to areas affected by occlusion, resulting in reduction of pain.

To us biofeedback is a rational approach as this offers a way of tackling the autonomic nervous system (ANS) dysregulation.  There are several small studies that have used biofeedback approaches in the past.

Thomas, J. E (1984) et al cited fifteen patients with a history of painful episodes of sickle cell disease that were given training in progressive relaxation, thermal biofeedback, cognitive strategies, and self-hypnosis to help them develop self-management skills to relieve pain. Results showed a 38.5% reduction in the number of emergency room visits, a 31% reduction in the number of hospitalisations, and a 50% reduction in the inpatient stay during the 6 months since the beginning of therapy compared to 6 months prior to therapy. Analgesic intake was reduced by 29% for those who were using it regularly. This was described as a preliminary study, and the results are considered only as suggestive of the potential use of biofeedback therapy and behavioral management in alleviating painful episodes in sickle cell disease.

Cozzi et al. (1987) investigated the effectiveness of electromyography and thermal biofeedback for reducing pain through a review of pain diaries as well as changes in muscle tension and body temperature. Eight patients ranging from 10 to 20 years of age kept a daily record of their level of pain based on a 5-point Likert scale.  Patients displayed statistically significant reductions in pain medication taken, reported pain intensity, and state anxiety.

Eight outpatients with sickle cell disease received six EMG and six thermal half-hour biofeedback training sessions. Statistically significant changes in the desired directions were obtained for the following variables: (a) frontalis muscle tension, (b) digital temperature, (c) frequency of headache as a crisis symptom, (d) frequency of analgesic use, (e) perceived pain intensity, (f) frequency of self-treated crises, and (g) state anxiety. Nonsignificant changes in hospital chart data were found. A 6-month posttreatment follow-up questionnaire revealed the continued effectiveness of the training received regarding headaches and mild pains.

Myrvik MP (2012) et al carried out a pilot study which evaluated single-session, biofeedback-assisted relaxation training (BART) for SCD pain in children. Ten participants (mean = 12.1 y) completed a 1-hour BART session using thermal biofeedback and home practice. Participants demonstrated changes in peripheral body temperature after the training session (d = 1.08) and at 6-week follow-up (d = 0.97) relative to their baseline visit. Reductions in patient-reported pain frequency were found after completing BART. Health-related quality of life and pain-related disability improvements were observed; however, effect sizes were small to minimal. The authors conclude that single-session BART may be a promising, complementary approach to medical management of paediatric SCD pain.

Discussion

We always should remember that biofeedback is primarily a process of learning that requires the patient's active participation. Like all learning, it matters a great deal how it is carried out and for how long.  So we need to take care in choosing what aspects of the ANS to sense, how to deliver feedback and how to guide the client's expectation.

Biofeedback has previously shown positive outomes when applied to reduce pain with SCD. We believe that this is entirely reasonable due to the fact that biofeedback and neurofeedback have been widely shown to be effective in dealing with autonomic nervous system dysregulation.  There are potentially a number of ways to approach this and the studies cited above have used a variety of sensors to "tap into" the status of the ANS. 

From experience we would suggest that the approach should be as personalised as possible. For example, in response to pain each client may exhibit different patterns of change in the ANS.  A "stress profile" using multiple sensors such as respiration rate, skin temperature, EDA and heart rate simultaneously observed, may show that the client exhibits the ANS dysregulation more dramatically via one or more sensors. This gives us a strong clue to which sensor signal we should use for feedback.

What about the type of feedback? For a paediatric client (or an adult for that matter) the nature of the feedback matters.  For example, with the NeXus system we might choose to use one of the Zukor games to make the feedback more engaging and reinforcing. Whilst the chosen signal remains above a carefully chosen level, the game can be played.  The threshold level must be chosen to reward influencing the ANS in a positive way but without causing frustration. This is a skill.

Pain medication when used has a prescribed dose, requires little involvement from the patient and this is in contrast with biofeedback which must have active participation to work. We see this as a good thing even though discussion on the "dose" of biofeedback and the need for personalised protocols can challenge established thinking on evidence of effectiveness.

References

Myrvik MP, Campbell AD, Butcher JL (2012)
Single-session biofeedback-assisted relaxation training in children with sickle cell disease.
J Pediatr Hematol Oncol. 2012 Jul;34(5):340-3.
DOI: 10.1097/MPH.0b013e318253f0ba.

Cozzi, L., Tryon, W. W., & Sedlacek, K. (1987).
The effectiveness of biofeedback-assisted relaxation in modifying sickle cell crises.
Biofeedback and Self-Regulation, 12, 51–61

Thomas, J. E., Koshy, M., Patterson, L., Dorn, L., & Thomas, K. (1984)
Management of pain in sickle cell disease using biofeedback therapy: A preliminary study.
Biofeedback and Self- Regulation, 9, 413–420.
DOI: 10.1007/BF01000558

Jones, JS; Hobbs,SA; Brennan, TL; and Schmidt, JM (2005)
Pain Assessment in Pediatric Sickle Cell Disease
Journal of Clinical Psychology in Medical Settings, Vol. 12, No. 4, December 2005 (
DOI: 10.1007/s10880-005-7820-2