Reliability of a Continuous Pain Score Meter: Real Time Pain Measurement

Gel instillation sonohysterography (GIS) using Endosgel versus ExEmgel, comparison of pain and image quality and cost benefit analysis: A double blind randomised controlled trial. GISPAIN trial

INTRODUCTION

Pain experience, physical reaction, image quality and adverse events during Gel Instillation Sonohysterography (GIS) can differ using gels with different compositions. As a result, patient satisfaction can also be affected. The effect of two instillation gels, Endosgel versus ExEmgel, using both the Visual Analogue Scale (VAS) and a Continuous Pain Score Meter (CPSM) was therefore compared.

METHODS

This single centre double blind randomised controlled trial included 80 women planned for outpatient GIS, diagnosed with abnormal intrauterine bleeding or fertility disorders and suspicion on an intrauterine abnormality. Patients were randomly allocated to the instillation of Endosgel containing chlorhexidine or ExEmgel without chlorhexidine. Primary outcome was reported pain during the procedure using VAS. Secondary outcomes included pain score measured using CPSM, satisfaction to the procedure and preference at 3 weeks and 3 months after the procedure and image quality. A cost benefit analysis was also performed.

RESULTS

The reported median VAS concerning pain during gel instillation was comparable in the Endosgel and ExEmgel group, 2.50 (IQR 0.00-5.00) and 2.00 (IQR 0.00-5.75) respectively (p = 0.69). The median VAS of the entire procedure was also similar: both 2.00 (IQR 0.00-5.00) (p = 0.86). CPSM-scores were not significantly different either. Both groups were similar in image quality (p = 0.83) and patient's satisfaction (p = 0.36).

CONCLUSION

Concerning the pain experienced during a GIS procedure and patients' satisfaction, the ExEmgel was not proven to be superior to the Endosgel. Our advice is to use the gel that is available at the lowest costs, as the image quality is the same for both Endosgel and ExEmgel.

Electronic Continuous Pain Measurement vs Verbal Rating Scale in gynaecology: A prospective cohort study

OBJECTIVE

To compare pain measured with a new electronic device - the Continuous Pain Score Meter (CPSM) - and the Verbal Rating Scale (VRS) during gynaecological procedures in an outpatient setting, and to correlate these outcomes with baseline anxiety and patient (in)tolerance to the procedure.

STUDY DESIGN

This prospective cohort study was undertaken in two centres: a university hospital and a large teaching hospital in The Netherlands. Patients undergoing an outpatient hysteroscopy, colposcopy or ovum pick-up procedure for in-vitro fertilization in one of the two participating hospitals with availability of the CPSM were included. Pain was measured by both the CPSM and the VRS. Patient tolerance to the procedure was reported. Various outcomes of the CPSM were compared with those of the VRS and related to baseline anxiety scores.

RESULTS

Ninety-one of 108 included patients (84 %) used the CPSM correctly during the procedure, and it was possible to analyse the CPSM scores for 87 women (81 %). The CPSM scores were all linearly related to the VRS. The peak pain score on the CPSM (CPSM-PPS) had the strongest correlation with the VRS score for all three procedures. Higher CPSM-PPS was related to patient (in)tolerance to the procedure (p = 0.03-0.002). Anxiety at baseline was not correlated with pain perception, except for VRS during colposcopy (r = 0.39, p = 0.016).

CONCLUSION

The majority of patients were able to use the CPSM correctly, resulting in detailed information on pain perception for each individual pain stimulus during three outpatient gynaecological procedures. The CPSM-PPS had the strongest correlation with the VRS score and patient (in)tolerance to the procedure.

Continuous assessment of labour pain using handgrip force

Pain is most frequently assessed in the clinical setting using scales such as numerical rating scales or visual analogue scales. However, these methods are not suitable for situations in which the experience of pain is dynamic and fluctuates widely – such as during parturition – because each rating requires an interaction with a health care worker. There are benefits to measuring the pain levels during these fluctuations – for example, the pattern of pain during contractions may be used to predict future contractions and optimize the use of patient-controlled analgesia. This study investigated the use of measurement of handgrip force using a dynamometer to represent patients’ pain levels during childbirth.

BACKGROUND:

Assessment of dynamic changes in painful experiences, such as labour, using conventional rating scales (eg, numerical rating scale [NRS]) has limitations. An alternative for continuous pain evaluation could be a signal generated by voluntary action of the parturient. Remifentanil administration for obstetric analgesia could be improved by these dynamic measures of labour pain. In the present study, handgrip force was measured by a dynamometer to signal labour pain.

OBJECTIVES:

To evaluate: whether continuous monitoring of labour pain using handgrip force allows for determination of pain measurement during contractions; and the correlation between handgrip force and pain intensity on NRS.

METHODS:

The present observational, single-centre study included 43 parturients. After calibration of the dynamometer for individual hand muscle strength, pain was recorded during early and late labour using a dynamometer and an NRS. The primary end point was the correlation coefficient between NRS ratings and peak intensity recorded by the dynamometer.

RESULTS:

All dynamometer-registered readings were also registered by the external tocogram. All contractions recorded by external tocogram were also registered by the dynamometer. Handgrip force was moderately correlated with pain scores on the NRS. Mean handgrip force during contractions had the highest correlation coefficient (Pearson’s r=0.67) compared with peak handgrip force (r=0.56) and area under the curve of handgrip force (r=0.55).

CONCLUSIONS:

Pain intensity and duration can be assessed continuously using handgrip force measured via a dynamometer. The feedback of intensity and duration of pain could optimize patient-controlled remifentantil application for obstetric analgesia and other situations of highly variable pain intensity.

Pain-preventing strategies in mammography: an observational study of simultaneously recorded pain and breast mechanics throughout the entire breast compression cycle

Background

Many women consider mammography painful. Existing studies on pain-preventing strategies only mention pain scores reported before and after breast compression. Studying the pain dynamics during the entire compression cycle may provide new insights for effective pain-preventing strategies.

Methods

This observational study included 117 women who consented to use a custom turning knob to indicate their pain experience during standard mammographic breast compressions in the Academic Medical Center in Amsterdam, The Netherlands. The breast thickness, compression force, contact area, contact pressure and pain experience were recorded continuously. Breast volume was calculated retrospectively from the mammograms. We visualized the progression of pain in relation to breast mechanics for five groups of breast volumes and we performed multivariable regressions to identify factors that significantly predict pain experience.

Results

Breast compressions consisted of a deformation phase for flattening, and a clamping phase for immobilization. The clamping phase lasted 12.8 ± 3.6 seconds (average ± standard deviation), 1.7 times longer than the 7.5 ± 2.6 seconds deformation phase. During the clamping phase, the average pain score increased from 4.75 to 5.88 (+24%) on a 0 – 10 Numerical Rating Scale (NRS), and the proportion of women who reached severe pain (NRS ≥ 7) increased from 23% to 50% (more than doubled). Moderate pain (NRS ≥ 4) was reported up to four days after the mammogram. Multivariable analysis showed that pain recollection of the previous mammogram and breast pain before the compression, are significant predictors for pain. Women with smallest breasts experienced most pain: They received highest contact pressures (force divided by contact area) and the pressure increased at the highest rate.

Conclusion

We suggest further research on two pain-preventing strategies: 1) using a personalized compression protocol by applying to all breasts the same target pressure at the same, slow rate, and 2) shortening the phase during which the breast is clamped.

One-stage full-mouth disinfection combined with a periodontal dressing: a randomized controlled clinical trial

AIM

To compare the clinical benefit of a periodontal dressing applied after a one-stage full-mouth disinfection (OSFMD) in patients with chronic periodontitis up to 3 months after therapy.

MATERIAL AND METHODS

This randomized, controlled split-mouth study included 24 patients. After OSFMD, a test and a control side were selected by means of a computer-generated randomization list. Test sides received a periodontal dressing (Coepak(®) ) for 7 days and the control sides received no periodontal dressing. After 7 days the periodontal dressing was removed and the pain experience was recorded. After 3 months, the clinical periodontal parameters were recorded.

RESULTS

The periodontal dressing group showed a significant (p < 0.05) additional pocket depth reduction and additional clinical attachment gain for the moderate pockets of single- and multi-rooted teeth compared with the control group. A significant (p < 0.05) lower percentage of sites with probing pocket depth ≥5 mm were shown for the periodontal dressing group compared with the control group (2.7 ± 16.3% versus 4.8 ± 21.4%). The pain intensity was significantly reduced when using a periodontal dressing (5.13 ± 0.89 versus 3.42 ± 1.27).

CONCLUSION

The use of a periodontal dressing for 7 days after a OSFMD offers an additional short-term clinical improvement and lowers the pain intensity.

A new tool for real-time pain assessment in experimental and clinical environments

Pain measurement largely depends on the ability to rate personal subjective pain. Nevertheless, pain scales can be difficult to use during medical procedures. We hypothesized that pain can be expressed intuitively and in real-time by squeezing a pressure sensitive device. We developed such a device called “Painmouse®” and tested it on healthy volunteers and patients in two separate studies: Sixteen male participants rated different painful heat stimuli via Painmouse® and a Visual Analog Scale (VAS). Retest was done one week later. Participants clearly distinguished four distinct pain levels using both methods. Values from the first and second sessions were comparable. Thereafter, we tested the Painmouse® by asking twelve female and male leg- ulcer patients to continuously squeeze it during the whole length of their wound-dressing change. Patients rated each step of dressing change on an 11-point numeric rating scale. Painmouse® ratings were highest for the wound cleaning and debridement step. Application of the new dressing was not evaluated as very painful. On the other hand, numeric scale ratings did not differentiate between dressing change steps. We conclude that the Painmouse® enables pain assessment even under difficult clinical circumstances, such as during a medical treatment in elderly patients.

Reliability and validity of a continuous pain registration procedure

BACKGROUND

Conventional pain rating scales [i.e. visual analogue scales (VAS) or numerical rating scales (NRS)] only provide a summary for different levels of pain felt, while the duration of these levels is not accounted for. If pain can be rated continuously, the area under the curve (AUC) of varying pain intensity over time can be calculated, which integrates varying pain intensity with duration. The present study examined the reproducibility and validity of a continuous pain rating procedure.

METHODS

Twenty-eight healthy volunteers participated. Pain was induced using constant current delivered to the non-dominant forearm using bipolar electrodes. Pain was rated continuously on an electronic VAS monitored by a computer. For each participant, the level of current needed to achieve a weak, mild, slightly moderate and moderate level of pain was determined (part I). Next, participants were asked to rate the painfulness of six periods of electrical stimulation (part II). Unknown to the participants, they were presented with the four levels of current obtained in part I, where the level of current for mild and moderate pain was presented twice (in order to assess consistency). The order of presentation was randomized for all subjects.

RESULTS

In general, participants produced reliable mean AUCs. In addition, the AUC of pain intensity over time could clearly discriminate between the four levels of pain used in the present study.

DISCUSSION

A continuous pain registration procedure, using an AUC approach, may be a promising direction to explore. Results can be improved by allowing more training on the use of the electronic VAS.