Effect of Age, Sex and Gender on Pain Sensitivity: A Narrative Review

Chronic sleep deficiency and its impact on pain perception in healthy females

Acute sleep deprivation in experimental studies has been shown to induce pain hypersensitivity in females. However, the impact of natural sleep deficiency and fluctuations across the week on pain perception remains unclear. A sleep-monitoring headband and self-reports were utilized to assess objective and subjective sleep in longer (> 6 hr) and short sleepers (< 6 hr). Pain sensitivity measures including heat, cold, pressure pain thresholds, pain inhibition (conditioned pain modulation) and facilitation (tonic pain summation) were assessed on Mondays and Fridays. Forty-one healthy young (23.9 ± 0.74 years) women participated. Short sleepers slept on average 2 hr less than longer sleepers (297.9 ± 8.2 min versus 418.5 ± 10.9 min) and experienced impaired pain inhibitory response (mean = -21.14 ± 7.9°C versus mean = 15.39 ± 9.5°C; p = 0.005). However, no effect was observed in pain thresholds and pain summation (p > 0.05). Furthermore, pain modulatory responses differed between Mondays and Fridays. Chronic sleep deficiency (< 6 hr) compromises pain responses, notably on Mondays. Maintaining a consistent sleep pattern with sufficient sleep (> 6 hr) throughout the week may protect against pain sensitization and the development of chronic pain in females. Further research is needed, especially in patients with chronic pain.

Sexual differences in neuronal and synaptic properties across subregions of the mouse insular cortex

BACKGROUND

The insular cortex (IC) plays a pivotal role in processing interoceptive and emotional information, offering insights into sex differences in behavior and cognition. The IC comprises two distinct subregions: the anterior insular cortex (aIC), that processes emotional and social signals, and the posterior insular cortex (pIC), specialized in interoception and perception of pain. Pyramidal projection neurons within the IC integrate multimodal sensory inputs, influencing behavior and cognition. Despite previous research focusing on neuronal connectivity and transcriptomics, there has been a gap in understanding pyramidal neurons characteristics across subregions and between sexes.

METHODS

Adult male and female C57Bl/6J mice were sacrificed and tissue containing the IC was collected for ex vivo slice electrophysiology recordings that examined baseline sex differences in synaptic plasticity and transmission within aIC and pIC subregions.

RESULTS

Clear differences emerged between aIC and pIC neurons in both males and females: aIC neurons exhibited distinctive features such as larger size, increased hyperpolarization, and a higher rheobase compared to their pIC counterparts. Furthermore, we observed variations in neuronal excitability linked to sex, with male pIC neurons displaying a greater level of excitability than their female counterparts. We also identified region-specific differences in excitatory and inhibitory synaptic activity and the balance between excitation and inhibition in both male and female mice. Adult females demonstrated greater synaptic strength and maximum response in the aIC compared to the pIC. Lastly, synaptic long-term potentiation occurred in both subregions in males but was specific to the aIC in females.

CONCLUSIONS

We conclude that there are sex differences in synaptic plasticity and excitatory transmission in IC subregions, and that distinct properties of IC pyramidal neurons between sexes could contribute to differences in behavior and cognition between males and females.

Pain mechanisms in the transgender individual: a review

Specific Aim

Provide an overview of the literature addressing major areas pertinent to pain in transgender persons and to identify areas of primary relevance for future research.

Methods

A team of scholars that have previously published on different areas of related research met periodically though zoom conferencing between April 2021 and February 2023 to discuss relevant literature with the goal of providing an overview on the incidence, phenotype, and mechanisms of pain in transgender patients. Review sections were written after gathering information from systematic literature searches of published or publicly available electronic literature to be compiled for publication as part of a topical series on gender and pain in the Frontiers in Pain Research.

Results

While transgender individuals represent a significant and increasingly visible component of the population, many researchers and clinicians are not well informed about the diversity in gender identity, physiology, hormonal status, and gender-affirming medical procedures utilized by transgender and other gender diverse patients. Transgender and cisgender people present with many of the same medical concerns, but research and treatment of these medical needs must reflect an appreciation of how differences in sex, gender, gender-affirming medical procedures, and minoritized status impact pain.

Conclusions

While significant advances have occurred in our appreciation of pain, the review indicates the need to support more targeted research on treatment and prevention of pain in transgender individuals. This is particularly relevant both for gender-affirming medical interventions and related medical care. Of particular importance is the need for large long-term follow-up studies to ascertain best practices for such procedures. A multi-disciplinary approach with personalized interventions is of particular importance to move forward.

DC/TMD axis I subtyping: generational and gender variations among East Asian TMD patients

OBJECTIVES

This study examined the generational-gender distinctions in Diagnostic Criteria for Temporomandibular disorders (DC/TMD) subtypes among East Asian patients.

METHODS

Consecutive "first-visit" TMD patients presenting at two university-based TMD/orofacial pain clinics in China and South Korea were enlisted. Demographic information along with symptom history was gathered and clinical examinations were performed according to the DC/TMD methodology. Axis I physical diagnoses were rendered with the DC/TMD algorithms and categorized into painful and non-painful TMDs. Patients were categorized into three birth cohorts, specifically Gen X, Y, and Z (born 1965-1980, 1981-1999, and 2000-2012 respectively) and the two genders. Data were evaluated using Chi-square/Kruskal-Wallis plus post-hoc tests and logistic regression analyses (α = 0.05).

RESULTS

Gen X, Y, and Z formed 17.2%, 62.1%, and 20.7% of the 1717 eligible patients examined (mean age 29.7 ± 10.6 years; 75.7% women). Significant differences in prevalences of arthralgia, myalgia, headache (Gen X ≥ Y > Z), and disc displacements (Gen Z > Y > X) were observed among the three generations. Gen Z had substantially fewer pain-related and more intra-articular conditions than the other generations. Women presented a significantly greater frequency of degenerative joint disease and number of intra-articular conditions than men. After controlling for generation-gender interactions, multivariate analyses showed that "being Gen X" and female increased the risk of painful TMDs (OR = 2.20) and reduced the odds of non-painful TMDs (OR = 0.46).

CONCLUSIONS

Generational-gender diversities in DC/TMD subtypes exist and are important for guiding TMD care and future research endeavors.

Sexual differences in neuronal and synaptic properties across subregions of the mouse insular cortex

Background

The insular cortex (IC) plays a pivotal role in processing interoceptive and emotional Information, offering insights into sex differences in behavior and cognition. The IC comprises two distinct subregions: the anterior insular cortex (alC), that processes emotional and social signals, and the posterior insular cortex (pIC), specialized in interoception and perception of pain. Pyramidal projection neurons within the IC integrate multimodal sensory inputs, influencing behavior and cognition. Despite previous research focusing on neuronal connectivity and transcriptomics, there has been a gap in understanding pyramidal neurons characteristics across subregions and between sexes.

Methods

Adult male and female C57BI/6J mice were sacrificed and tissue containing the IC was collected for ex vivo slice electrophysiology recordings that examined baseline sex differences in synaptic plasticity and transmission within alC and pIC subregions.

Results

Clear differences emerged between alC and pIC neurons In both males and females: alC neurons exhibited distinctive features such as larger size, increased hyperpolarizatlon, and a higher rheobase compared to their pIC counterparts. Furthermore, we observed variations in neuronal excitability linked to sex, with male pIC neurons displaying a greater level of excitability than their female counterparts. We also identified region-specific differences in excitatory and inhibitory synaptic activity and the balance between excitation and inhibition in both male and female mice. Adult females demonstrated greater synaptic strength and maximum response in the alC compared to the pIC. Lastly, synaptic long-term potentiation occurred in both subregions in males but was specific to the alC in females.

Conclusions

We conclude that there are sex differences in synaptic plasticity and excitatory transmission in IC subregions, and that distinct properties of IC pyramidal neurons between sexes could contribute to differences in behavior and cognition between males and females.

Sexual differences in neuronal and synaptic properties across subregions of the mouse insular cortex

Background

The insular cortex (IC) plays a pivotal role in processing interoceptive and emotional information, offering insights into sex differences in behavior and cognition. The IC comprises two distinct subregions: the anterior insular cortex (aIC), that processes emotional and social signals, and the posterior insular cortex (pIC), specialized in interoception and perception of pain. Pyramidal projection neurons within the IC integrate multimodal sensory inputs, influencing behavior and cognition. Despite previous research focusing on neuronal connectivity and transcriptomics, there has been a gap in understanding pyramidal neurons characteristics across subregions and between sexes.

Methods

Adult male and female C57Bl/6J mice were sacrificed and tissue containing the IC was collected for ex vivo slice electrophysiology recordings that examined baseline sex differences in synaptic plasticity and transmission within aIC and pIC subregions.

Results

Clear differences emerged between aIC and pIC neurons in both males and females: aIC neurons exhibited distinctive features such as larger size, increased hyperpolarization, and a higher rheobase compared to their pIC counterparts. Furthermore, we observed variations in neuronal excitability linked to sex, with male pIC neurons displaying a greater level of excitability than their female counterparts. We also identified region-specific differences in excitatory and inhibitory synaptic activity and the balance between excitation and inhibition in both male and female mice. Adult females demonstrated greater synaptic strength and maximum response in the aIC compared to the pIC. Lastly, synaptic long-term potentiation occurred in both subregions in males but was specific to the aIC in females.

Conclusions

We conclude that there are sex differences in synaptic plasticity and excitatory transmission in IC subregions, and that distinct properties of IC pyramidal neurons between sexes could contribute to differences in behavior and cognition between males and females.

Highlights

- Distinctions specific to sex are present within subregions of the insular cortex (IC) in C57Bl/6J mice.- Pyramidal neurons in the anterior IC (aIC) exhibited larger size and distinct electrical properties. Adult females exhibited stronger synaptic responses in the aIC.- Conversely, male posterior insular cortex neurons displayed increased excitability.- Synaptic long-term potentiation was observed in both subregions in males, but it was exclusive to the aIC in females.- Sex-based variations in various aspects of excitatory transmission within IC subregions could contribute to differences in behavior and cognition between males and females.

Plain language summary

This study investigates differences in the insular cortex (IC), a region of the brain responsible for emotions and sensory perceptions, between male and female mice. The IC has two parts: the front (aIC) deals with emotions and social cues, while the back (pIC) is focused on sensing pain and bodily sensations. We examined specific brain cells called pyramidal neurons in both aIC and pIC and discovered noteworthy distinctions between these neurons in adult male and female mice. Firstly, aIC neurons were larger and had unique electrical properties in both male and female mice. Males had more excitable pIC neurons compared to females, indicating that their neurons were more likely to transmit signals. We also explored how these neurons communicate with each other through connections known as synapses. In adult females, the aIC had stronger connections than the pIC. Finally, we observed that specific types of basic synaptic learning occurred exclusively in males in the aIC.These findings underscore significant disparities in the IC between males and females, offering valuable insights into the potential reasons behind variations in behaviors and emotions between sexes.

Gender differences in interactions and depressive symptoms among hospitalized older patients living with dementia

Alzheimer's disease or a related dementia (ADRD) disproportionately affects women with two-thirds of individuals with ADRD comprised of women. This study examined gender-related differences in the quality of staff-patient interactions and depressive symptoms among hospitalized older patients living with dementia. This secondary analysis utilized baseline data of 140 hospitalized older patients with dementia who participated in the final cohort of a randomized controlled trial (ClinicalTrials.gov identifier: NCT03046121) implementing Family centered Function-focused Care (Fam-FFC). On average, the participants (male = 46.1%, female = 52.9%) were 81.43 years old (SD = 8.29), had positive interactions with staff and lower depressive symptoms based on Quality of Interaction Schedule (QUIS) scores and Cornell Scale for Depression in Dementia (CSDD) scores, respectively. Although males had more positive interactions (male = 6.06, SD = 1.13; female = 5.59, SD = 1.51) and lesser depressive symptoms (male = 7.52, SD = 4.77; female = 8.03, SD = 6.25) than females, no statistically significant gender differences were observed in linear models with appropriate covariates or multivariant analysis of covariant (MANCOVA). However, the multigroup regression conducted to further probe marginally significant moderation effect of gender and pain on staff-patient interactions demonstrated that greater pain was significantly related to lower quality or less positive staff-patient interactions for females compared to males (χ2diff (1) = 4.84, p = .03). Continued evaluation of gender differences is warranted to inform care delivery and interventions to improve care for hospitalized older patients with dementia.

Prospective paired crossover evaluation of potential impact of investigator gender on perceived pain intensity early after acute or scheduled surgery

BACKGROUND

Postoperative pain is common but often difficult to assess, and there are many potential confounders. Over the last decades, the gender of investigator as well as participant has been found to influence pain perception in both preclinical and clinical studies. However, to our knowledge this has not been studied in various postoperative patients. Objectives of this study were to test the hypotheses that pain intensity levels early after acute or scheduled in- or out-hospital surgery are lower when evaluated by a female investigator, and higher when reported by a female patient.

METHODS

In this prospective observational paired crossover study, two investigators of opposite genders independently obtained individually reported pain intensity levels with a visual analogue scale in a mixed cohort of adult postoperative study patients at Skåne University Hospital in Malmö, Sweden.

RESULTS

In total, 245 (129 female) study patients were included and then one female excluded. The study patients rated their intensity of postoperative pain lower when evaluated by a female than by a male investigator (P = 0.006), where the male patients constituted the significant difference (P < 0.001). Pain intensity levels did not differ between female and male study patients (P = 0.210).

CONCLUSIONS

Main findings of lower pain intensity reported by males to a female than to a male investigator early after surgery in this paired crossover study in mixed postoperative patients, indicate that potential impact of investigator gender on pain perception should be considered and further evaluated in clinical bedside practice. Trial registration Retrospectively registered in the ClinicalTrials.gov research database on 24th June 2019 with TRN number NCT03968497.

Chiropractic Care and Quality of Life Among Office Workers With Nonspecific Pain: A Cross-Sectional Study

Objective

The aim of this study was to evaluate the quality of life by a self-administered World Health Organization Quality of Life short version survey (WHOQoL-BREF) among office workers with nonspecific pain receiving chiropractic care in Istanbul, Turkey.

Methods

This cross-sectional study included 77 office workers (age interval, 18-65) with nonspecific neck, thoracic, back and/or extremity pain who underwent chiropractic care. Two weeks later, the quality of life was evaluated by a self-administered WHOQoL-BREF. The Numeric Pain Scale to evaluate the perceived pain was administered to all of the participants in the beginning and at the end of the study. Group-level changes on WHOQoL-BREF total score and subdimensions were compared according to descriptive data of office workers. The significance level was set at P ≤ .05.

Results

WHOQoL-BREF scale scores after chiropractic care (mean ± standard deviation) were 71.21% ± 7.91% (total score), 81.49% ± 14.43% (general health), 80.38% ± 10.49% (physical health), 73.16% ± 11.68% (psychological), 70.41% ± 12.43% (social), and 65.58% ± 10.91% (environment). Numeric Pain Scale scores decreased in a statistically significant way when compared with baseline (P ≤ .05). The descriptive statistical analysis of WHOQoL-BREF dimensions revealed that women had significantly higher scores than men, the 18-to-35 age group had higher scores compared with the 50-to-65 age group, and those married had significantly higher scores than those who were not married (P ≤ .05).

Conclusion

The findings of our study suggest that chiropractic care had positive effects on the quality of life of office workers.

Vapocoolant Spray for Pain Control in Intramuscular Injection Applications: A Prospective, Randomized Controlled Trial

Background Many pharmacological and nonpharmacological methods have been investigated along with advances in pain treatment. One of these nonpharmacological methods is the use of vapocoolant spray.

Objective This study aimedto demonstrate the effectiveness of vapocoolant spray to reduce pain during intramuscular (IM) injection.

Patients and Methods The study included ≥18 years old patients admitted to the emergency department who were asked to undergo IM injection. Patients were randomly divided into two groups as vapocoolant spray and control group. Demographic data, injection side, and visual analog scale (VAS) of the patients were recorded.

Results Mean VAS values during IM injection were significantly lower in patients treated with vapocoolant spray compared with the control group. The severity of pain during IM injection was lower in the vapocoolant spray group as both moderate pain (VAS > 3 cm) and severe pain (VAS > 5.4 cm) compared with the control group.

Conclusion Vapocoolant spray to be applied before IM injection is effective in reducing pain caused by the injection.

Randomized cross-over evaluation of investigator gender on pain thresholds in healthy volunteers

Background and aims: This randomized cross-over study in healthy volunteers was designed primarily to evaluate the potential impact of investigator gender on electrical pain threshold (EPT) and corresponding pain intensity levels, and secondly to evaluate potential differences in those interventions between female and male study participants. Methods: Forty adult volunteers (22 females) were included. An electrical stimulation device was used to determine EPT levels (in pain magnitude scores) in series of three in each study participant - once by a female, and once by a male investigator - according to a predefined cross-over design schedule. Corresponding levels of pain intensity were scored on a visual analog scale (VAS) slide ruler. Results: Study data was obtained and analysed in all participants. Significantly higher EPT levels were determined by the female investigator compared with the male investigator (median 22 (IQR 12-31) vs. 8 (6-10) pain magnitude scores; p<0.0001), despite similar levels of reported pain intensity (1.9 (1.2-3.0) vs. 2.0 (1.1-3.4) VAS units; p>0.300). There were no differences in EPT levels between female and male subjects evaluated by female (p>0.300) and male (p=0.125) investigators, or between the first and second series of stimulation (p>0.300). Conclusions: Our finding of significantly higher EPT levels when study participants of both genders - despite no difference in reported pain intensity - were evaluated by a female than by a male investigator, indicates a potential impact of investigator gender on the individual perception of pain. Implications: By contributing to a better understanding of how individual pain threshold levels are potentially influenced by investigator gender, this study might facilitate future evaluation of pain conditions in both preclinical and clinical settings.

An Assessment of Dental Anxiety in Patients Before and After Scaling and Polishing Procedures

Introduction As of now, there are not many investigations about the improvement of dental apprehension and dental participation in various populations over time. This investigation includes an examination of emotional appraisals of levels of dental apprehension in patients selected at the AB Shetty Memorial Institute of Dental Sciences. The investigation also aimed to discover the causes of dental apprehension as well as the effect of sexuality on the distinguished dental apprehension.

Materials and Methods The level of dental apprehension was assessed using questionnaires that included 15 questions before and after the scaling and polishing procedures for 78 patients. The typical features were drawn such as gender, age, and oral hygiene habits. The data analysis was analyzed using paired t-test or Wilcoxon signed rank test to assess pre- and postanxiety levels.

Results A total of 78 responses were collected, resulting in a participation rate of 100%. Despite the fact that women had significantly higher overall dental apprehension levels compared with men, the discrepancy among the two genders was substantial and could be clarified.

Conclusion Dental fear was common in females, especially among those with dental problems, and a larger degree of dental fear can contribute to periodontal disease.

The relationship between pain severity and sleep quality: Posttube thoracostomy

BACKGROUND

The presence of a chest tube is a factor significantly associated with pain and pain posttube thoracostomy that negatively affects sleep quality (SQ).

AIM

To determine the relationship between the pain severity and SQ of patients who underwent the tube thoracostomy (TT).

METHODS

This was a descriptive and cross-sectional survey conducted from May 1, 2018, to December 30, 2018, in the thoracic surgery department of Sivas Cumhuriyet University Hospital in Central Anatolia/Turkey. Data were collected using a questionnaire form, a Numerical Rating Scale to determine pain severity, and the Richard-Campbell Sleep Questionnaire to assess SQ.

RESULTS

The study was carried out with 102 patients who underwent the TT. The mean age of the participants were 48.94 years. The mean scores for the scale items indicated that during the procedure and on the first day of post-TT, the pain severity of the patients was very high, their SQ was low. Pain level decreased gradually in the following days, and the SQ increased. There was a positive, strong correlation between the post-TT first day pain and first night SQ (r = 0.380, p = 0.000), second day pain and second night SQ (r = -0.537, p = 0.000), and third day pain and third night SQ (r = -0.507, p = 0.000).

CONCLUSION

The results of this study highlight that the pain severity of post-TT significantly affect the quality of the patients' night sleep.

Patient-reported pain severity and health-related quality of life in patients with multiple myeloma in real world clinical practice

BACKGROUND

The association between patient self-reported pain severity and health-related quality-of-life (HRQoL) is poorly understood.

AIMS

This real-world study of symptomatic multiple myeloma (MM) patients sought to determine how pain severity from a single question asked during routine clinical consultation was associated with HRQoL.

METHODS AND RESULTS

Point-in-time data on HRQoL of 330 patients with MM (median age 70 years) receiving anti-myeloma therapy in Germany and Italy from November 2017 through February 2018 were analyzed. HRQoL was assessed using validated questionnaires (Work Productivity and Activity Impairment [WPAI], European Organization for Research and Treatment of Cancer Quality of Life Questionnaire -C30 and -MY20). Physical pain severity was assessed during clinical consultation by a single question, asking patients to describe their pain as "no pain," "mild," "moderate," or "severe." Associations between patient-reported pain severity and HRQoL scores were assessed by analysis of variance or χ² tests. Ninety-six of the 330 patients (29.1%) reported moderate to severe pain. Increase in pain severity, from "no" to "severe" pain, was associated with significantly decreased overall HRQoL (mean score 70.2 to 33.3); significant decreases in levels of physical (82.7 to 35.1), social (81.1 to 44.4), emotional (78.1 to 48.3), and role functioning (79.5 to 38.9); and increased levels of WPAI usual activity impairment (35.4 to 71.4), and fatigue burden (26.0 to 68.9) (all p < .001).

CONCLUSION

Higher pain severity, based on a single self-report question, was associated with poorer HRQoL in patients with MM, thereby supporting the clinical relevance of directly asking patients to self-evaluate their pain severity.

Comparative study on the effect of hyperthermic massage and mechanical squeezing in the patients with mild and severe meibomian gland dysfunction: An interventional case series

BACKGROUND

Meibomian glands exist beneath the palpebral conjunctiva; thus, it is invisible to the naked eye without infrared imaging. This study used meibography to group patients with meibomian gland dysfunction (MGD) and assessed the effects of hyperthermic massage and mechanical squeezing in both groups.

MATERIALS AND METHODS

Patients with MGD were divided into two groups, according to the degree of meibomian gland loss: group 1, in which the sum of eyelid scores ranged from 0 to 4 (mild to moderate gland loss) and group 2, in which the sum of eyelid scores ranged from 5 to 6 (severe gland loss). Hyperthermic massage and mechanical squeezing were given to both groups once a week for 4 weeks, and only non-preservative artificial tears were allowed. Ocular surface disease index (OSDI), Schirmer's test, meibography score, tear break-up time (TBUT), ocular surface staining, expressible meibomian gland, and quality before and after treatment were compared.

RESULTS

Of the 49 patients who completed the 4 weeks of treatment and the evaluation at week 5, 29 were assigned to group 1 and 20 were assigned to group 2. Meibography scores, OSDI, TBUT, and expressibility of meibum had significant differences before and after treatments in both groups. However, there was no significant difference between the changes in clinical signs between group 1 and 2 after treatment. Without grouping, all patients showed significant decreases in meibography score, OSDI, cornea staining score, and increases in TBUT and expressibility of meibum after treatment.

CONCLUSIONS

Considering the results of the current study, hyperthermic massage and mechanical squeezing may be effective in patients with meibomian gland loss, regardless of the degree of severity.

Impact of the Timing of Rocuronium Injection after Propofol Administration on Temporal Summation of Pain in Gynecologic Laparoscopic Surgery: A Prospective and Controlled Study

Purpose

Temporal summation of pain, which is defined as the perception of greater pain evoked by repetitive painful stimuli, varies among individuals. This study aimed at determining the impact of the timing of rocuronium after induction with propofol on the temporal summation of pain.

Methods

One hundred patients aged 19–60 years underwent gynecologic laparoscopic surgery. Patients were randomly assigned to one of the two groups: group PRi received immediate injections of rocuronium after propofol administration and group PRd received rocuronium injections when the bispectral index score (BIS) decreased to <60 after propofol administration. The grade of rocuronium-induced withdrawal movement (RIWM) according to the timing of propofol injection, the incidence and severity of propofol injection pain (PIP), rescue analgesics, visual analog scale (VAS) score after surgery for postoperative pain, patient-controlled analgesia (PCA) opioid consumption, association between PIP and the grade of RIWM, and associations between PIP, the grade of RIWM, and postoperative pain outcomes were measured.

Results

The differences between the incidence and severity of PIP in the two groups were not significant. The grade of the RIWM in the PRd group was significantly reduced compared with the PRi group. Rescue analgesics, severity for postoperative pain, and PCA opioid consumption were not significant. Correlations between the incidence and severity of PIP and the grade of RIWM were weakly negative. Correlations between the grade of RIWM and pain outcomes were moderately positive, but correlations between the severity for PIP and the postoperative pain outcomes were negligible.

Conclusion

The timing of rocuronium administration after propofol injection played a role in reducing RIWM. The grade of RIWM was significantly related to pain outcomes compared with the severity of PIP. Therefore, delayed rocuronium injection after induction with propofol reduced temporal summation of pain.

Is topical lidocaine beneficial before catheter insertion in esophageal manometry and ambulatory pH monitoring?

BACKGROUND

Conventionally, topical anesthesia is applied to improve the tolerance of esophageal manometry (EM) and ambulatory pH monitoring (apH) but there is presently no evidence supporting this practice. We aimed to compare the tolerance of EM and apH with vs without topical lidocaine anesthesia.

METHODS

A prospective study was conducted at our center between January 2017 and January 2019. All patients who underwent EM or apH and completed a systematically distributed standardized patient survey were included. From January 2017 to June 2018, all patients had a viscous lidocaine solution applied before EM and apH ("lidocaine" group). After June 2018, we ceased applying any topical anesthesia ("no lidocaine" group). Patient-reported adverse effects and satisfaction scores were compared between these two patient groups.

KEY RESULTS

Two hundred forty-nine patient surveys were included. "Lidocaine" (n = 124) and "no lidocaine" (n = 125) groups were similar in age (56.9 ± 14.0 vs 56.0 ± 13.7; P = .77) and gender distributions (65.9% vs 63.3% female; P = .68). Patients in the "lidocaine" group were less likely to report pain during catheter insertion (33.6% vs 50.8%; P = .007, OR: 0.49 [95% CI 0.29-0.83]) and reported a lower overall pain score (2.82 ± 1.38 vs 3.20 ± 1.42 on 5; P = .04). There was a tendency toward increased global satisfaction with lidocaine application but that was not statistically significant (4.36 ± 1.05 vs 4.11 ± 1.13; P = .08). In subgroup analyses, female patients, younger patients, and patients who underwent EM were more likely to benefit from lidocaine application.

CONCLUSIONS AND INFERENCES

Application of topical lidocaine before esophageal motility tests reduces pain during catheter insertion and overall pain.