Pain Scales: What Are They and What Do They Mean

PURPOSE OF REVIEW

It is essential to have validated and reliable pain measurement tools that cover a wide range of areas and are tailored to individual patients to ensure effective pain management. The main objective of this review is to provide comprehensive information on commonly used pain scales and questionnaires, including their usefulness, intended purpose, applicability to different patient populations, and associated advantages and disadvantages.

RECENT FINDINGS

Acute pain questionnaires typically focus on measuring the severity of pain and the extent of relief achieved through interventions. Chronic pain questionnaires evaluate additional aspects such as pain-related functional limitations, psychological distress, and psychological well-being. The selection of an appropriate pain scale depends on the specific assessment objectives. Additionally, each pain scale has its strengths and limitations. Understanding the differences among these pain scales is essential for selecting the most appropriate tool tailored to individual patient needs in different settings.

CONCLUSION

Medical professionals encounter challenges in accurately assessing pain. Physicians must be familiar with the different pain scales and their applicability to specific patient population.

Effect of adding hip exercises to general rehabilitation treatment of knee osteoarthritis on patients' physical functions: a randomized clinical trial

BACKGROUND

Hip adductor and abductor strength were both reduced in KOA patients. But to date, most of the researches have only focused on quadriceps combined with hip abductor strengthening versus quadriceps strengthening.

OBJECTIVE

The aim of the study is to evaluate the effect of adding hip abductor and adductor strengthening to quadriceps strengthening on lower limb strength, knee pain and physical function in patients with medial compartmental knee osteoarthritis.

METHODS

In this study, 42 participants, were randomly divided into two groups: the general treatment group (GT group) and the added-hip-exercise group (AH group). All participants were given a general rehabilitation treatment. The AH group performed hip abductor and adductor strengthening in addition to the general rehabilitation treatment. Knee and hip muscle strength, Five Times Sit-to-Stand Test (FTSST), the Timed Up and Go Test (TUGT), Numerical Rating Scale (NRS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were assessed at baseline and 6 weeks. A two-sided 2-sample unpaired t test was performed to compare the difference in mean change scores between AH and GT groups.

RESULTS

Finally, 36 participants completed the study: both groups consist of 18 participants. In the per-protocol analysis, the AH group had a greater improvement in knee extension strength (mean changes, 7.84 versus 36.48; P < 0.001) and hip abduction strength (mean changes, 5.05 versus 26.62; P = 0.001) than the control group. Similarly, the AH group had a greater improvement in the FTSST time (mean changes, 0.40 s versus 3.57 s; P < 0.001) and the TUFT time (mean changes, 0.18 s versus 1.67 s; P = 0.002) than the GH group. No statistical difference was found in the change of WOMAC pain scores and NRS between the 2 groups.

CONCLUSIONS

Older adults with knee OA in the AH group had superior muscle strength, symptoms and daily activity performance at the 6th week than those in the GT group. And adding hip exercises could expedite improvement of pain at the 2th week, but not at the 6th week.

TRIAL REGISTRATION

Clinical trial registration numbers and date of registration: ChiCTR-IOR-16009124, Registered 30 August 2016.

Two cases of low back pain of unknown etiology diagnosed as multiple myeloma

We report two cases of patients complaining of lumbar back pain of unknown etiology which were finally diagnosed as multiple myeloma. The first case was a woman in her 80s with a chief complaint of lumbar back pain. The second case was a male in his 70s. He also consulted our institution because his pain did not subside despite receiving increased doses of oral medication and nerve blocks from his previous doctor. Both patients presented with compression fractures on plain radiography, and additionally with cytopenia, hyperproteinemia, and hypoalbuminemia in blood tests. Further tests were conducted due to suspected multiple myeloma, revealing a punched-out legion in the skull and elevated levels of β2 microglobulin and Immunoglobulin G. Subsequently, both patients were transferred to the hematology department. In these two cases, we had predicted the presence of multiple myeloma from the results of initial testing and subsequently successfully provided definitive diagnoses following additional examinations.

Clinical correlates of pain in adults with hard-to-heal leg ulcers: a cross-sectional study

OBJECTIVE

Pain is a complex symptom associated with hard-to-heal (chronic) leg ulcers that is often poorly managed. The objective of this study was to gain greater understanding by investigating relationships between physical and psychosocial factors, and pain severity in adults with hard-to-heal leg ulcers.

METHOD

A secondary analysis of data collected for a longitudinal, observational study of adults with hard-to-heal leg ulcers was undertaken. Data were collected over a 24-week period, including variables relating to sociodemographics, clinical variables, medical status, health, ulcer and vascular histories, and psychosocial measures. Multiple linear regression modelling was used to determine the independent influences of these variables on pain severity, as measured with a Numerical Rating Scale (NRS).

RESULTS

Of 142 participants who were recruited, 109 met the inclusion criteria for this study, of whom: 43.1% had venous ulcers; 41.3% had mixed ulcers; 7.3% had arterial ulcers; and 8.3% had ulcers from some other cause. The final model explained 37% (adjusted r²=0.370) of the variation in the pain NRS scores. Controlling for analgesic use, salbutamol use (p=0.005), clinical signs of infection (p=0.027) and ulcer severity (p=0.001) were significantly associated with increased pain, while the presence of diabetes (p=0.007) was significantly associated with a decrease in pain.

CONCLUSION

Pain is a highly complex and pervasive symptom associated with hard-to-heal leg ulcers. Novel variables were identified as being associated with pain in this population. The model also included wound type as a variable; however, despite being significantly correlated to pain at the bivariate level of analysis, in the final model, the variable did not reach significance. Of the variables included in the model, salbutamol use was the second most significant. This is a unique finding that, to the authors' knowledge, has not been previously reported or studied. Further research is required to better understand these findings and pain in general.

Bilateral transversus thoracis muscle plane block provides effective analgesia and enhances recovery after open cardiac surgery

BACKGROUND

The mid-sternum is the main source of pain after open cardiac surgery. The aim of this study was to investigate the effect of bilateral transversus thoracis muscle plane (TTMP) blocks on open cardiac surgery.

METHODS

Sixty patients were randomly divided into two groups: bilateral TTMP blocks (TP group) or no nerve block (CO group). The primary endpoint was perioperative sufentanil consumption. The secondary outcome measures included postoperative pain, flurbiprofen axetil administration, quality of sleep after extubation, time to extubation, time to the return of gastrointestinal function, time to drain removal, the Intensive Care Unit (ICU) stay time, and hospital stay.

RESULTS

The TP group reported significantly less sufentanil and flurbiprofen axetil consumption than the CO group. The CO group had higher Numerical Rating Scale (NRS) pain scores at 1, 2, 6, 12, and 24 h after extubation both at rest and during movement than the TP groups. Compared with the CO group，time to extubation, time to the first bowel movement, ICU stay time, and hospital stay were significantly decreased in the TP group. The TP group was rated as better in the quality of the two nights of sleep after extubation.

CONCLUSION

Bilateral TTMP blocks can provide good perioperative analgesia for patients undergoing open cardiac surgery and promote postoperative recovery.

Validity and Utility of Four Pain Intensity Measures for Use in International Research

Background

The majority of previous research that has examined the validity of pain intensity rating scales has been conducted in western and developed countries. Research to evaluate the generalizability of previous findings in non-developed countries is necessary for identifying the scales that are most appropriate for use in international research.

Purpose

The aims of the current study were to (1) evaluate the validity and utility of four commonly used measures of pain intensity in a sample of patients with chronic pain from Thailand and (2) compare findings in the current sample with published findings from research conducted in other countries, in order to identify the measure or measures which might be most appropriate for cross-country research.

Methods

Three hundred and sixty patients with chronic pain seen in a hospital in Bangkok, Thailand, were asked to rate their current pain and average, worst, and least pain intensity in the past week using the Visual Analogue Scale (VAS), 6-point Verbal Rating Scale (VRS-6), 0–10 Numerical Rating Scale (NRS-11), and Faces Pain Scale-Revised (FPS-R). We evaluated the utility and validity of each measure by examining the (1) rates of correct responding and (2) association of each measure with a factor score representing the variance shared across measures, respectively. We also evaluated the associations between incorrect response rates and both age and education level, and then compared the findings from this sample with the findings from research conducted in other countries.

Results

The results indicated support for the validity of all measures among participants who were able to use these measures. However, there was variability in the incorrect response rates, with the VAS having the highest (45%) and the NRS-11 having the lowest (15%) incorrect response rates. The VAS was also the least preferred (9%) and the NRS-11 the most preferred (52%) scale. Education and age were significantly associated with incorrect response rates, and education level with scale preference.

Conclusion

The findings indicate that the NRS-11 has the most utility in our sample of Thai individuals with chronic pain. However, when considered in light of the findings from other countries, the results of this study suggest that the FPS-R may have the most utility for use in cross-cultural and international research. Research in additional samples in developing countries is needed to evaluate the generalizability of the current findings.

Using a clinical judgement model to understand the impact of validated pain assessment tools for burn clinicians and adult patients in the ICU: A multi-methods study

BACKGROUND

Intensive care (ICU) patients' burn pain is difficult to assess, communicate and address, risking chronic pain syndromes and psychological morbidity.

AIMS

To understand how the introduction of validated pain tools (Critical Care Pain Observation Tool [CPOT], Numerical Rating Scale [NRS], Pain Assessment in Advanced Dementia [PAINAD]) affected clinical judgement processes, analgesia/sedation administration and the experience of burn-injured patients.

METHODS

Consecutive chart review compared type and amount of analgesia/sedation administered, ventilation time and length of ICU/hospital stay between consecutive burn patients pre- and 6-months post-intervention (n=70). Analysis of 36 qualitative interviews with ICU clinicians (n=12) and burn-injured adults (n=12) pre- and post-intervention was guided by Tanner's (2006) Clinical Judgement Model.

RESULTS

Overall, there was a significant increase in morphine (P=0.04) and propofol (P=0.04) use and a trend towards increased paracetamol (P=0.06) use post-intervention. There was a trend towards greater Midazolam use for TBSA<20% (P=0.06), and significantly increased propofol use for TBSA≥20% (P=0.03). Ventilation time and ICU/hospital length of stay were unchanged. Qualitative analysis revealed complex clinical judgement dependent on the context of the patient's situation, unit culture, background beliefs of clinicians and in knowing the patient. Whilst the CPOT and NRS enhanced analytic reasoning and pain advocacy, the PAINAD appeared redundant.

CONCLUSIONS

Effective pain assessment, management and advocacy are assisted by evidence-based assessment practices.

A randomized control trial to compare thoracic epidural with intercostal block plus intravenous morphine infusion for postoperative analgesia in patients undergoing elective thoracotomy

Objective

The objective of the study is to compare the efficacy of Thoracic epidural with Intercostal block plus intravenous morphine infusion for postoperative analgesia in patients undergoing elective thoracotomy.

Methodology and Design

This study is designed as a prospective randomized clinical trial. Setting: Christian Medical College Hospital, Vellore, India.

Participants

Patients undergoing elective thoracic surgery through posterolateral thoracotomy.

Intervention

In Group A (TEA) patients epidural catheter was inserted at T5-6 level before induction of GA and analgesia was activated using 0.25% of bupivacaine towards the end of the surgery, before chest closure and infusion of 0.1% bupivacaine with 2 mcg/ml of fentanyl was started. In Group B (ICN) patients, an intercostal blockade of the 5 intercostal spaces was performed by the surgeon just before chest closure using 0.25% bupivacaine and a continuous intravenous morphine infusion of 0.015-0.02 mg/kg/hr was started.

Measurements

Assessment of resting and dynamic pain intensity using Numerical rating scale and sedation using Ramsay sedation scale was done and recorded at 1, 6,12,18,24 hours during the first postoperative day. The other parameters that were measured include side effects and the requirement of rescue analgesia. Results: Resting and Dynamic (NRS) pain scores were less in Group A (TEA) than Group B (ICN). In the first 12 hours, the differences in both the resting (P = 0.0505) and dynamic (P = 0.0307) pain scores were statistically significant. By the end of the first postoperative day, sedation scores were more or less similar in both groups. The incidence of side effects and requirement of rescue analgesia were found to be similar in both the groups.

Conclusion

To summarize, though the results show a slightly better quality of analgesia with the thoracic epidural, the difference being clinically insignificant intercostal blockade could be considered as a valid alternative.

Comparison of Single-Dose Infraclavicular Brachial Plexus Block and Continuous Infraclavicular Brachial Plexus Block Applications in the Treatment of Finger Amputations

Introduction The aim of this study is to evaluate the replantation success of single-dose infraclavicular brachial plexus block and continuous infraclavicular brachial plexus block (CIBPB) applied with bupivacaine and prilocaine in patients with finger amputation. Materials and Methods This prospective randomized nonblinded study was conducted between January 2012 and September 2017, and 47 patients, all male, were included. Patients were randomly separated into two groups as 23 patients CIBPB applied group (group A) and 24 patients single-dose infraclavicular block applied group (group B). In group B, after the effect of block is ceased, intravenous patient-controlled (PC) opioid analgesia and, where necessary, 1 mg/kg meperidine and 75 mg diclofenac sodium intramuscularly were alternately administered at 4 to 6 hours intervals. The average ages were 30.7 ± 10.06 and 29 ± 9.08, respectively. Replantations were applied as being two venous anastomoses to one artery, where possible. Hourly skin temperatures of fingers of the hands in which both surgeries applied and no surgery applied in both the groups were measured for 3 days with an infrared thermometer. Also, Numerical Rating Scale (NRS) evaluations in both the groups were performed in 3-hour intervals for 3 days. Results Replantations were successful in 22 patients in whom CIBPB was applied (95.6%) and in 19 patients in whom single block was applied (79.16%). Regarding the finger temperatures, no significant difference was detected between both the groups for 3 days following the operation. No significant difference was found between the length of hospital stays (4.73 ± 2.21-4.71 ± 1.53) and duration of operations (2.90 ± 0.73-2.83 ± 0.58). There was no significant difference between the temperature values of both the groups. NRS scores of group A were statistically significantly lower than those of group B. Conclusion In this prospective randomized study performed by using bupivacaine and prilocaine on 24 patients, the success rate of finger replantations with CIBPB was found to be higher. CIBPB is a very beneficial method that should be taken in consideration in hand injuries with anastomosis and high risk of vasospasm. Further studies with more number of cases would help reduce the question marks related with the success of this method.

Comparison of Subcostal Transversus Abdominis Block with Intraperitoneal Instillation of Levobupivacaine for Pain Relief after Laparoscopic Cholecystectomy: A Prospective Study

Background

There are several methods employed in the management of postoperative pain after laparoscopic cholecystectomy such as conventional systemic analgesics, including paracetamol, non-steroidal anti-inflammatory drugs, systemic opioids, and thoracic epidural analgesia with all having its limitations and side effects.

Aims

The present study aims to compare ultrasound-guided subcostal transversus abdominis (STA) block with intraperitoneal instillation of levobupivacaine in reducing postoperative pain, total analgesic consumption, nausea and vomiting, and recovery time in patients after elective laparoscopic cholecystectomy.

Settings and Design

A prospective study was conducted between January 2017 and December 2017 in 80 patients undergoing elective laparoscopic cholecystectomy after approval of the Institutional Ethical Committee (Reference No: SGRR/IEC/05/16).

Materials and Methods

Patients were randomly divided into two equal-sized (n = 40) study groups. Group 1 patients received ultrasonography-guided STA block with 0.25% levobupivacaine both sides and Group 2 patients received 0.25% levobupivacaine through intraperitoneal route.

Statistical Analysis

Quantitative data were expressed in mean and standard deviation. Qualitative data were expressed in proportion and percentages. Independent t-test was applied to compare the means of quantitative data and the Chi-square test was used to compare categorical data. P < 0.05 was considered to be statistically significant. Survival curve was drawn using the log-rank test for comparing two groups.

Results

Patient characteristics regarding age, gender, and weight were comparable in the two groups. The mean Numerical Rating Scale scores were less in Group 1 than in Group 2 in the first 6 h, which was found to be statistically significant. There was no significant difference noted in pain scores after 6 h up to 24 h in postoperative area among the two groups. Pain scores for shoulder tip pain were lower in Group 2 as compared to Group 1 in the first 24 h, which was not significant statistically.

Conclusion

STA block is a better modality for analgesia compared to intraperitoneal instillation in patients undergoing elective laparoscopic cholecystectomy.

Reliability of measurements for sub-painful and painful perception on artificial electrical stimulations

Artificial electrical stimulation is a common type of stimulus to induce sub-painful and painful sensation in clinical or neuroscience experiments. The Numerical Rating Scale (NRS) is often used to evaluate subjective perception due to external stimulations. Yet the relationship between the intensity levels of electrical stimulations and self-perception has seldom been examined. The aim of the study was to obtain evidence on the reliability and accuracy of sub-painful and painful perceptions of healthy participants using the NRS under different levels of electrical stimulus. A total of 72 pain-free healthy volunteers (female=44) were recruited. In the first experiment, each participant was given different levels of a non-nociceptive or nociceptive electrical stimulus and then asked to give a perception rating based on an 11-point NRS. In the second experiment, each participant was asked to memorize 5 levels of sub-nociceptive or nociceptive stimuli and to recognize the level of stimulus given each time. For the NRS rating task, intraclass coefficients (ICCs) reached satisfactory level for sub-nociceptive (0.85<ICC<0.93) and nociceptive stimulation (0.90<ICC<0.96). The ICCs were the highest for the weakest sub-nociceptive and nociceptive stimuli. For the stimulus recognition task, accuracy was also found to be highest for the weakest sub-nociceptive stimulus (κ=0.67) and lowest for the strongest nociceptive stimulus (κ=0.34). The results suggest that, with adequate training, NRS can be a reliable measurement tool for both sub-painful and painful rating due to electrical stimulation.

Comparison between the Visual Analog Scale and the Numerical Rating Scale in the perception of esthetics and pain

BACKGROUND

Pain is an unpleasant, emotional, and sensorial experience. Esthetics and pain express perceptions or sensations that are subjective and personal, but non-consensual, between professionals and patients. The Visual Analog Scale (VAS) and the Numerical Rating Scale (NRS) are simple methods to evaluate such subjective phenomena.

OBJECTIVE

To verify whether a concordance exists between VAS and NS in the perception of esthetics and pain.

MATERIAL AND METHODS

Regarding esthetics, an on-line questionnaire was prepared with extra- and intra-oral images (adapted). The order of the scales was alternated between interwoven and sequential. Regarding perception of pain, respondents personally classified its intensity at the present moment, or over the past 30 days.

RESULTS

A statistically significant concordance (P<0.001) - positive and moderate - was found between the scales, for the evaluation of both the extra- and intra-oral images, r=0.678 and 0.638, respectively. Regarding pain perception, taking formal education into account, no concordance was found between the two scales for participants who had "no formal education" (P>0.05). The concordance between the scales increased proportionally with the level of education.

CONCLUSION

There was a concordance between the scales with regard to esthetical perception and the evaluation of pain. When assessing esthetics, the order in which the two scales are applied does not affect the concordance between them. However, the strength of the concordance is influenced. Esthetic perception is not influenced by the differences between the panels of evaluators. The concordance between the two scales, for the evaluation of pain, increases proportionally with the level of formal education.

Assessing Pruritus in Hidradenitis Suppurativa: A Cross-Sectional Study

BACKGROUND

Pruritus is still a forgotten aspect of hidradenitis suppurativa (HS) and, to date, has never been adequately studied.

OBJECTIVE

The aim of this study was to determine the prevalence, and explore the characteristics, of pruritus in a well-defined cohort of HS patients.

SETTING

An academic hospital-based cross-sectional study in The Netherlands.

METHODS

A numerical rating scale (NRS, 0-10) was used to determine the prevalence of HS-related itch (NRS score ≥3). Candidate predictors for pruritus were subsequently determined using logistic regression models, and the impact of pruritus was assessed using a modified five-dimensional (5-D) itch scale. Associated serological and histological markers of pruritus were (semi-)quantitatively investigated in a subpopulation.

RESULTS

The prevalence rate of pruritus in 211 HS patients was 57.3%, with a mean NRS score of 6.1 ± 2.0. Patients with a pruritus NRS score ≥3 had more HS-affected body sites than patients with a score <3 (p < 0.001). The occurrence of a pruritus NRS score ≥3 was associated with Hurley III disease (odds ratio [OR] 7.73; p = 0.003) and pain (OR 1.34; p < 0.001). Pruritus affected sleep and activities of daily living (ADL) in the majority of cases, with an associated modified 5-D itch score of 13.7 ± 3.6 (on a scale from 5 to 25) in 52 HS patients. Histological examination showed eosinophilic granulocytes were present in 25% (2/8) of the perilesional skin and 63% (10/16) of the lesional skin, while a perineural infiltrate was found in 25% (2/8) and 69% (11/16) of the perilesional and lesional skin, respectively.

CONCLUSION

Pruritus is a frequent but underreported symptom in patients with HS. Its moderate to severe intensity and significant impact on daily activities have great potential to impair patients' quality of life.

Practical Dyspnea Assessment: Relationship Between the 0-10 Numerical Rating Scale and the Four-Level Categorical Verbal Descriptor Scale of Dyspnea Intensity

CONTEXT

Measurement of dyspnea is important for clinical care and research.

OBJECTIVES

To characterize the relationship between the 0-10 Numerical Rating Scale (NRS) and four-level categorical Verbal Descriptor Scale (VDS) for dyspnea assessment.

METHODS

This was a substudy of a double-blind randomized controlled trial comparing palliative oxygen to room air for relief of refractory breathlessness in patients with life-limiting illness. Dyspnea was assessed with both a 0-10 NRS and a four-level categorical VDS over the one-week trial. NRS and VDS responses were analyzed in cross section and longitudinally. Relationships between NRS and VDS responses were portrayed using descriptive statistics and visual representations.

RESULTS

Two hundred twenty-six participants contributed responses. At baseline, mild and moderate levels of breathlessness were reported by 41.9% and 44.6% of participants, respectively. NRS scores demonstrated increasing mean and median levels for increasing VDS intensity, from a mean (SD) of 0.6 (±1.04) for VDS none category to 8.2 (1.4) for VDS severe category. The Spearman correlation coefficient was strong at 0.78 (P < 0.0001). Based on the distribution of NRS scores within VDS categories, we calculated test characteristics of two different cutpoint models. Both models yielded 75% correct translations from NRS to VDS; however, Model A was more sensitive for moderate or greater dyspnea, with fewer misses downcoded.

CONCLUSION

There is strong correlation between VDS and NRS measures for dyspnea. Proposed practical cutpoints for the relationship between the dyspnea VDS and NRS are 0 for none, 1-4 for mild, 5-8 for moderate, and 9-10 for severe.