Preoperative sleep quality predicts postoperative pain after planned caesarean delivery

Brief Assessment of Patient Phenotype to Explain Variability in Postsurgical Pain and Opioid Consumption after Cesarean Delivery: Performance of a Novel Brief Questionnaire Compared to Long Questionnaires

BACKGROUND

Understanding factors that explain why some women experience greater postoperative pain and consume more opioids after cesarean delivery is crucial to building an evidence base for personalized prevention. Comprehensive psychosocial assessment with validated questionnaires in the preoperative period can be time-consuming. A three-item questionnaire has shown promise as a simpler tool to be integrated into clinical practice, but its brevity may limit the ability to explain heterogeneity in psychosocial pain modulators among individuals. This study compared the explanatory ability of three models: (1) the 3-item questionnaire, (2) a 58-item questionnaire (long) including validated questionnaires (e.g., Brief Pain Inventory, Patient Reported Outcome Measurement Information System [PROMIS]) plus the 3-item questionnaire, and (3) a novel 19-item questionnaire (brief) assessing several psychosocial factors plus the 3-item questionnaire. Additionally, this study explored the utility of adding a pragmatic quantitative sensory test to models.

METHODS

In this prospective, observational study, 545 women undergoing cesarean delivery completed questionnaires presurgery. Pain during local anesthetic skin wheal before spinal placement served as a pragmatic quantitative sensory test. Postoperatively, pain and opioid consumption were assessed. Linear regression analysis assessed model fit and the association of model items with pain and opioid consumption during the 48 h after surgery.

RESULTS

A modest amount of variability was explained by each of the three models for postoperative pain and opioid consumption. Both the brief and long questionnaire models performed better than the three-item questionnaire but were themselves statistically indistinguishable. Items that were independently associated with pain and opioid consumption included anticipated postsurgical pain medication requirement, surgical anxiety, poor sleep, pre-existing pain, and catastrophic thinking about pain. The quantitative sensory test was itself independently associated with pain across models but only modestly improved models for postoperative pain.

CONCLUSIONS

The brief questionnaire may be more clinically feasible than longer validated questionnaires, while still performing better and integrating a more comprehensive psychosocial assessment than the three-item questionnaire.

EDITOR’S PERSPECTIVE

Prediction of early postoperative pain using sleep quality and heart rate variability

PURPOSE

Accurate predictions of postoperative pain intensity are necessary for customizing analgesia plans. Insomnia is a risk factor for severe postoperative pain. Moreover, heart rate variability (HRV) can provide information on the sympathetic-parasympathetic balance in response to noxious stimuli. We developed a prediction model that uses the insomnia severity index (ISI), HRV, and other demographic factors to predict the odds of higher postoperative pain.

METHODS

We recruited gynecological surgery patients classified as American Society of Anesthesiologists class 1-3. An ISI questionnaire was completed 1 day before surgery. HRV was calculated offline using intraoperative electrocardiogram data. Pain severity at the postanesthesia care unit (PACU) was assessed with the 0-10 numerical rating scale (NRS). The primary outcome was the model's predictive ability for moderate-to-severe postoperative pain. The secondary outcome was the relationship between individual risk factors and opioid consumption in the PACU.

RESULTS

Our study enrolled 169 women. Higher ISI scores (p = 0.001), higher parasympathetic activity (rMSSD, pNN50, HF; p < 0.001, p < 0.001, p < 0.001), loss of fractal dynamics (SD2, alpha 1; p = 0.012, p = 0.039) in HRV analysis before the end of surgery were associated with higher NRS scores, while laparoscopic surgery (p = 0.031) was associated with lower NRS scores. We constructed a multiple logistic model (area under the curve = 0.852) to predict higher NRS scores at PACU arrival. The five selected predictors were age (OR: 0.94; p = 0.020), ISI score (OR: 1.14; p = 0.002), surgery type (laparoscopic or open; OR: 0.12; p < 0.001), total power (OR: 2.02; p < 0.001), and alpha 1 (OR: 0.03; p < 0.001).

CONCLUSION

We employed a multiple logistic regression model to determine the likelihood of moderate-to-severe postoperative pain upon arrival at the PACU. Physicians could personalize analgesic regimens based on a deeper comprehension of the factors that contribute to postoperative pain.

The prevalence and risk factors of sleep disturbances in surgical patients: A systematic review and meta-analysis

Determining the prevalence and risk factors related to sleep disturbance in surgical patients would be beneficial for risk stratification and perioperative care planning. The objectives of this systematic review and meta-analysis are to determine the prevalence and risk factors of sleep disturbances and their associated postoperative complications in surgical patients. The inclusion criteria were: (1) patients ≥18 years old undergoing a surgical procedure, (2) in-patient population, and (3) report of sleep disturbances using a validated sleep assessment tool. The systematic search resulted in 21,951 articles. Twelve patient cohorts involving 1497 patients were included. The pooled prevalence of sleep disturbances at preoperative assessment was 60% (95% Confidence Interval (CI): 50%, 69%) and the risk factors for postoperative sleep disturbances were a high preoperative Pittsburgh sleep quality index (PSQI) score indicating preexisting disturbed sleep and anxiety. Notably, patients with postoperative delirium had a higher prevalence of pre- and postoperative sleep disturbances and high preoperative wake after sleep onset percentage (WASO%). The high prevalence of preoperative sleep disturbances in surgical patients has a negative impact on postoperative outcomes and well-being. Further work in this area is warranted.

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Pretreatment of the ROS Inhibitor Phenyl-N-tert-butylnitrone Alleviates Sleep Deprivation-Induced Hyperalgesia by Suppressing Microglia Activation and NLRP3 Inflammasome Activity in the Spinal Dorsal Cord

Sleep deprivation, a common perioperative period health problem, causes ocular discomfort and affects postsurgical pain. However, the mechanism of sleep deprivation-induced increased pain sensitivity is elusive. This study aims to explore the role of ROS in sleep deprivation (SD)-induced hyperalgesia and the underlying mechanism. A 48-h continuous SD was performed prior to the hind paw incision pain modeling in mice. We measured ROS levels, microglial activation, DNA damage and protein levels of iNOS, NLRP3, p-P65 and P65 in mouse spinal dorsal cord. The involvement of ROS in SD-induced prolongation of postsurgical pain was further confirmed by intrathecal injection of ROS inhibitor, phenyl-N-tert-butylnitrone (PBN). Pretreatment of 48-h SD in mice significantly prolonged postsurgical pain recovery, manifesting as lowered paw withdrawal mechanical threshold and paw withdrawal thermal latency. It caused ROS increase and upregulation of iNOS on both Day 1 and 7 in mouse spinal dorsal cord. In addition, upregulation of NLRP3 and p-P65, microglial activation and DNA damage were observed in mice pretreated with 48-h SD prior to the incision. Notably, intrathecal injection of PBN significantly reversed the harmful effects of SD on postsurgical pain recovery, hyperalgesia, microglial activation and DNA damage via the NF-κB signaling pathway. Collectively, ROS increase is responsible for SD-induced hyperalgesia through activating microglial, triggering DNA damage and enhancing NLRP3 inflammasome activity in the spinal dorsal cord.

Auricular acupuncture for sleep quality in participants with mental and behavioral disorders due to prior multiple drug use: a retrospective consecutive case series

BACKGRUOUND

Poor sleep quality is associated with psychoactive substance abuse/addiction/withdrawal. Auricular acupuncture (AA) is a nonpharmacological method used for the treatment of sleep disturbances. This study aimed to examine the quality of sleep before and after AA in participants with mental and behavioral disorders due to prior multiple drug use in the therapeutic community.

METHODS

This was a consecutive case series of 27 participants (25 male [92.6%]). The median age was 35.0 years (interquartile range [IQR], 29.0-37.2 years), methadone/buprenorphine were not used, and the participants were treated with AA (median number of treatments, 15.0 [IQR, 12.0-18.0]) during a median period of 51.0 days (IQR, 49.0-51.0 days) according to the National Acupuncture Detoxification Association (NADA)-Acudetox protocol. Sleep quality was determined using the Pittsburgh Sleep Quality Index (PSQI), a self-rated questionnaire that assesses sleep quality and disturbances over a 1-month interval.

RESULTS

The global PSQI score dropped (indicating better sleep quality) by a median of 3.0 points (IQR, 0.0-8.0 points) after treatment. In the multivariate logistic regression analysis, with an increase in global PSQI score during AA by 1 point, there was a 0.73-fold reduction in the risk of poor sleep quality post-AA (adjusted odds ratio, 0.73; 95% confidence interval, 0.52-1.01; p<0.055; Nagelkerke's R2=0.66).

CONCLUSION

The results revealed a positive effect of AA (by the NADA-Acudetox protocol) on sleep quality (as measured by PSQI) among participants in a treatment center with mental and behavioral disorders due to multiple drug use.

Development of a novel intervention to improve sleep and pain in patients undergoing total knee replacement

Background

Up to 20% of patients experience long-term pain and dissatisfaction after total knee replacement, with a negative impact on their quality of life. New approaches are needed to reduce the proportion of people to go on to experience chronic post-surgical pain. Sleep and pain are bidirectionally linked with poor sleep linked to greater pain. Interventions to improve sleep among people undergoing knee replacement offer a promising avenue. Health beliefs and barriers to engagement were explored using behaviour change theory. This study followed stages 1–4 of the Medical Research Council’s guidance for complex intervention development to develop a novel intervention aimed at improving sleep in pre-operative knee replacement patients.

Methods

Pre-operative focus groups and post-operative telephone interviews were conducted with knee replacement patients. Before surgery, focus groups explored sleep experiences and views about existing sleep interventions (cognitive behavioural therapy for insomnia, exercise, relaxation, mindfulness, sleep hygiene) and barriers to engagement. After surgery, telephone interviews explored any changes in sleep and views about intervention appropriateness. Data were audio-recorded, transcribed, anonymised, and analysed using framework analysis.

Results

Overall, 23 patients took part, 17 patients attended pre-operative focus groups, seven took part in a post-operative telephone interview, and one took part in a focus group and interview. Key sleep issues identified were problems getting to sleep, frequent waking during the night, and problems getting back to sleep after night waking. The main reason for these issues was knee pain and discomfort and a busy mind. Participants felt that the sleep interventions were generally acceptable with no general preference for one intervention over the others. Views of delivery mode varied in relation to digital move and group or one-to-one approaches.

Conclusion

Existing sleep interventions were found to be acceptable to knee replacement patients. Key barriers to engagement related to participants’ health beliefs. Addressing beliefs about the relationship between sleep and pain and enhancing understanding of the bidirectional/cyclical relationship could benefit engagement and motivation. Individuals may also require support to break the fear and avoidance cycle of pain and coping. A future intervention should ensure that patients’ preferences for sleep interventions and delivery mode can be accommodated in a real-world context.

The importance of sleep for people with chronic pain: current insights and evidence

We are currently in the midst of a sleep crisis. Our current work and lifestyle environments are normalizing poor sleep with substantial negative impact on our health. Research on sleep has linked sleep deprivation to poorer mental health, obesity, cancer, diabetes, heart disease, and a myriad of other health conditions. Sleep deprivation is an even greater issues for people with musculoskeletal conditions and chronic pain. Between 67% and 88% of individuals with chronic pain experience sleep disruption and insomnia, and at least 50% of people with insomnia report chronic pain. The link between sleep and pain is well documented. Experimental, cohort, and longitudinal studies have all demonstrated that restricted sleep is linked to greater pain. Poor sleep therefore not only affects general health but has a direct impact on inflammation, pain response, and experience. Improving sleep in people living with musculoskeletal conditions and with chronic pain has the potential to deliver great benefit to many. This article describes the evidence base that can underpin such work, including research about the link between pain and sleep as well as theories and approaches to intervention that may help. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

The effectiveness of non-pharmacological sleep interventions for people with chronic pain: a systematic review and meta-analysis

Objective

About two thirds of people with chronic pain report problems sleeping. We aimed to evaluate the effectiveness of non-pharmacological sleep interventions for improving sleep in people with chronic pain.

Design

We conducted a systematic review of non-pharmacological and non-invasive interventions to improve sleep quality or duration for adults with chronic non-cancer pain evaluated in a randomised controlled trial. Our primary outcome of interest was sleep; secondary outcomes included pain, health-related quality of life, and psychological wellbeing. We searched the Cochrane Library, MEDLINE, Embase, PsycINFO and CINAHL from inception to April 2020. After screening, two reviewers evaluated articles and extracted data. Meta-analysis was conducted using a random effects model. Risk of bias was assessed with the Cochrane tool.

Results

We included 42 trials involving 3346 people randomised to 94 groups, of which 56 received an intervention targeting sleep. 10 studies were of fair and 32 of good methodological quality. Overall risk of bias was judged to be low in 11, high in 10 and unclear in 21 studies. In 9 studies with 385 people randomised, cognitive behavioural therapy for insomnia showed benefit post-treatment compared with controls for improved sleep quality, standardised mean difference − 1.23 (95%CI -1.76, − 0.70; p < 0.00001). The effect size was only slightly reduced in meta-analysis of 3 studies at low risk of bias. The difference between groups was lower at 3 and 6 months after treatment but still favoured cognitive behavioural therapy for insomnia. Pain, anxiety and depression were reduced post-treatment, but evidence of longer term benefit was lacking. There was no evidence that sleep hygiene interventions were effective in improving sleep and there was some evidence in comparative studies to suggest that cognitive behavioural therapy for insomnia was more effective than sleep hygiene.

Numerous other interventions were evaluated in small numbers of studies, but evidence was insufficient to draw conclusions about effectiveness.

Conclusions

Cognitive behavioural therapy for insomnia is an effective treatment to improve sleep for people with chronic pain, but further high-quality primary research is required to explore combined CBT content that will ensure additional improvements to pain, quality of life and psychological health and longer-term maintenance of benefits. Primary research is also needed to evaluate the effectiveness of interventions for which insufficient evidence exists.

Trial registration

PROSPERO registration number: CRD42019093799.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05318-5.

Multimodal prediction of pain and functional outcomes 6 months following total knee replacement: a prospective cohort study

BACKGROUND

Knee osteoarthritis (OA) is among the most common and disabling persistent pain conditions, with increasing prevalence and impact around the globe. In the U.S., the rising prevalence of knee OA has been paralleled by an increase in annual rates of total knee arthroplasty (TKA), a surgical treatment option for late-stage knee OA. While TKA outcomes are generally good, post-operative trajectories of pain and functional status vary substantially; a significant minority of patients report ongoing pain and impaired function following TKA. A number of studies have identified sets of biopsychosocial risk factors for poor post-TKA outcomes (e.g., comorbidities, negative affect, sensory sensitivity), but few prospective studies have systematically evaluated the unique and combined influence of a broad array of factors.

METHODS

This multi-site longitudinal cohort study investigated predictors of 6-month pain and functional outcomes following TKA. A wide spectrum of relevant biopsychosocial predictors was assessed preoperatively by medical history, patient-reported questionnaire, functional testing, and quantitative sensory testing in 248 patients undergoing TKA, and subsequently examined for their predictive capacity.

RESULTS

The majority of patients had mild or no pain at 6 months, and minimal pain-related impairment, but approximately 30% reported pain intensity ratings of 3/10 or higher. Reporting greater pain severity and dysfunction at 6 months post-TKA was predicted by higher preoperative levels of negative affect, prior pain history, opioid use, and disrupted sleep. Interestingly, lower levels of resilience-related "positive" psychosocial characteristics (i.e., lower agreeableness, lower social support) were among the strongest, most consistent predictors of poor outcomes in multivariable linear regression models. Maladaptive profiles of pain modulation (e.g., elevated temporal summation of pain), while not robust unique predictors, interacted with psychosocial risk factors such that the TKA patients with the most pain and dysfunction exhibited lower resilience and enhanced temporal summation of pain.

CONCLUSIONS

This study underscores the importance of considering psychosocial (particularly positively-oriented resilience variables) and sensory profiles, as well as their interaction, in understanding post-surgical pain trajectories.

Sleep and gynecological cancer outcomes: opportunities to improve quality of life and survival

Sleep is important for immune function, metabolic function and physical repair. Sleep is more commonly disrupted in women compared with men and is disrupted by surgery, chemotherapy, and cancer itself, making gynecological oncology patients at higher risk of insomnia and sleep disruption. Insomnia and sleep disruption are linked to increased pain, poorer quality of life, depression, and anxiety which can all negatively affect patient outcomes. A number of environmental, behavioral, and pharmacological interventions have been investigated to improve patient sleep and aid in the recovery process. It is vital to understand and address patient sleep quality in order to give patients the highest quality care and improve outcomes.

The Effect of Improving Preoperative Sleep Quality on Perioperative Pain by Zolpidem in Patients Undergoing Laparoscopic Colorectal Surgery: A Prospective, Randomized Study

Methods

A prospective, randomized study was conducted with 88 patients undergoing laparoscopic colorectal surgery. The experimental group (S group, n = 44) was given 10 mg of zolpidem tartrate one night before the surgical procedure, while no medication was given to the control group (C group, n = 44). The primary outcome was the intraoperative remifentanil consumption. Sufentanil consumption, average patient-controlled analgesia (PCA) effective press times, the visual analog scale (VAS) scores, and incidences of postoperative nausea and vomiting (PONV) were recorded at 6 h (T1), 12 h (T2), and 24 h (T3) postoperatively.

Results

The intraoperative remifentanil consumption was significantly lower in the S group than that in the C group (p < 0.01). Sufentanil consumption at 6 h and 12 h postoperatively was significantly lower in the S group than that in the C group (p < 0.05); average PCA effective press times and VAS scores, at 6 h and 12 h postoperatively, were significantly lower in the S group than those in the C group (p < 0.01); differences between groups 24 h postoperatively were not significant. No significant between-group difference was noted in the incidence of nausea and vomiting.

Conclusion

Improving patients' sleep quality the night before surgical procedure by zolpidem can decrease the usage of intraoperative analgesics and reduce postoperative pain.

Effects of Melatonin Treatment on Perioperative Sleep Quality: A Systematic Review and Meta-Analysis with Trial Sequential Analysis of Randomized Controlled Trials

PURPOSE

Perioperative sleep disorders have attracted much attention due to their high prevalence and severe harm, and the current treatment methods are insufficient. Some randomized controlled trials (RCTs) have produced controversial results on whether melatonin can improve perioperative sleep quality. This review aimed to evaluate the effects of melatonin treatment on perioperative sleep quality.

PATIENTS AND METHODS

A systematic search of six databases was performed to identify RCTs investigating melatonin and perioperative sleep. The outcomes analyzed were subjective sleep quality, sleep latency (SL), total sleep time (TST), sleep efficiency (SE), the behavior of awakenings and daily naps, and the incidence of poor sleep quality. RevMan 5.4 and Stata 16 software was used for the meta-analysis and sensitivity analysis, and trial sequential analysis was conducted using TSA 0.9.5.10 Beta software. This study was registered in PROSPERO (registration number: CRD42022311378).

RESULTS

10 studies containing 725 participants were included. Melatonin improved postoperative subjective sleep quality (SMD: -0.30; 95% CI: [-0.47, -0.14]; P = 0.0004) but not preoperative sleep quality (MD: -2.76; 95% CI: [-10.44, 4.91]; P = 0.48). In the postoperative period, 6mg dose had the best efficacy (SMD: -0.31; 95% CI: [-0.57, -0.04]; P = 0.02). Melatonin increased postoperative TST (P = 0.02) and SE (P = 0.002) and decreased the incidence of postoperative poor sleep quality (P = 0.002) but had no effect on SL (P = 0.11), the number and duration of awakenings (P = 0.28; P=0.55), and the number and duration of daily naps (P = 0.26; P = 0.38). The trial sequential analysis showed that the accumulated Z value crossed both the traditional boundary value and the TSA boundary value, further confirming the stability of the result of the meta-analysis.

CONCLUSION

Melatonin treatment can improve postoperative sleep quality. A 6mg daily dose of melatonin may have a better beneficial effect, which needs further exploration. This study supports the application of melatonin for improving postoperative sleep quality.

Intranasal Dexmedetomidine for the Treatment of Pre-operative Anxiety and Insomnia: A Prospective, Randomized, Controlled, and Clinical Trial

BACKGROUND AND OBJECTIVE

Several patients with pre-operative anxiety and insomnia refuse to take sleeping pills because of the side effects of sleeping pills. This study aimed to evaluate the applicability of intranasal dexmedetomidine (DEX) in the treatment of pre-operative anxiety and insomnia.

METHODS

A total of 72 patients with insomnia and anxiety were randomly divided into two groups of intranasal DEX (n = 36) and intranasal normal saline (NS, n = 36). The primary outcomes included patients' time to fall asleep, total sleep time, insomnia severity index (ISI) after treatment, and satisfaction with the treatment effect. The secondary outcomes were mean arterial pressure (MAP), oxygen saturation (SPO₂), heart rate (HR), Narcotrend index (NI) in the first 2 h of treatment, and the incidence of adverse events within 12 h after treatment.

RESULTS

The time to fall asleep (22.08 ± 3.95 min) and total sleep time (400.06 ± 28.84 min) in the DEX group were significantly different from those in the NS group [time to fall asleep, 89.31 ± 54.56 min; total sleep time (295.19 ± 73.51 min; P < 0.001)]. ISI after treatment in the DEX group was lower than that in the NS group (P < 0.001). Satisfaction with the treatment effect was better in the DEX group than that in the NS group (P < 0.001). The general vital signs in the two groups were stable during the treatment. The drowsiness rate in the NS group was higher than that in the DEX group (P < 0.001).

CONCLUSION

Intranasal DEX can significantly improve pre-operative anxiety and insomnia.

CLINICAL TRIAL REGISTRATION

This study was registered on Chinese Clinical Trial Registry (http://www.chictr.org.cn/searchproj.aspx, ChiCTR2100044747).

Intraoperative pain during caesarean delivery: Incidence, risk factors and physician perception

BACKGROUND

Intraoperative pain is a possible complication of neuraxial anaesthesia for caesarean delivery. There is little information available about its incidence, risk factors and physician perception.

METHODS

Parturients undergoing spinal anaesthesia for elective caesarean delivery were enrolled. Before surgery, parturients were asked about preoperative anxiety on a verbal numerical scale (VNS), anticipated analgesic requirement, postoperative pain levels, Spielberger STATE-TRAIT inventory index, Pain Catastrophizing Scale. After surgery, parturients were asked to answer questions (intraoperative VNS pain). The anaesthesiologist and obstetrician were asked to fill out a questionnaire asking about perceived intraoperative pain. Influence of preoperative anxiety on intraoperative pain (yes/no) was assessed using logistic regression. Mc Fadden's R² was calculated. The agreement in physician perception of intraoperative pain with reported pain by the parturient was examined by calculating Cohen's kappa and 95% Confidence Intervals (CI).

RESULTS

We included 193 parturients in our analysis. Incidence of intraoperative pain was 11.9%. Median intraoperative VNS pain of parturients with pain was 4.0 (1st quartile 4.0; 3rd quartile 9.0). Preoperative anxiety was not a good predictor of intraoperative pain (p-value of β-coefficient = 0.43, Mc Fadden's R²  = 0.01). Including further preoperative variables did not result in a good prediction model. Cohen's kappa between reported pain by parturient and by the obstetrician was 0.21 (95% CI: 0.01, 0.41) and by the anaesthesiologist was 0.3 (95% CI: 0.12, 0.48).

CONCLUSIONS

We found a substantial incidence (11.9%) of intraoperative pain during caesarean delivery. Preoperative anxiety did not predict intraoperative pain. Physicians did not accurately identify parturients' intraoperative pain.

SIGNIFICANCE

Intraoperative pain occurred in 11.9% and severe intraoperative pain occurred in 1.11% of parturients undergoing elective caesarean delivery under spinal anaesthesia. We did not find any preoperative variables that could reliably predict intraoperative pain. Obstetricians and anaesthesiologists underestimated the incidence of intraoperative pain in our cohort and thus, more attention must be put to parturients' pain.

Labor prior to cesarean delivery associated with higher post-discharge opioid consumption

Background

Severe acute post-cesarean delivery (CD) pain has been associated with an increased risk for persistent pain and postpartum depression. Identification of women at increased risk for pain can be used to optimize post-cesarean analgesia. The impact of labor prior to CD (intrapartum CD) on acute post-operative pain and opioid use is unclear. We hypothesized that intrapartum CD, which has been associated with both increased inflammation and affective distress related to an unexpected surgical procedure, would result in higher postoperative pain scores and increased opioid intake.

Methods

This is a secondary analysis of a prospective cohort study examining opioid use up to 2 weeks following CD. Women undergoing CD at six academic medical centers in the United States 9/2014-3/2016 were contacted by phone two weeks following discharge. Participants completed a structured interview that included questions about postoperative pain scores and opioid utilization. They were asked to retrospectively estimate their maximal pain score on an 11-point numeric rating scale at multiple time points, including day of surgery, during hospitalization, immediately after discharge, 1^st week, and 2^nd week following discharge.

Pain scores over time were assessed utilizing a generalized linear mixed-effects model with the patient identifier being a random effect, adjusting for an a priori defined set of confounders. A multivariate negative binomial model was utilized to assess the association between intrapartum CD and opioid utilization after discharge, also adjusting for the same confounders. In the context of non-random prescription distribution, this model was constructed with an offset for the number of tablets dispensed.

Results

A total of 720 women were enrolled, 392 with and 328 without labor prior to CD. Patients with intrapartum CD were younger, less likely to undergo repeat CD or additional surgical procedures, and more likely to experience a complication of CD.

Women with intrapartum CD consumed more opioid tablets following discharge than women without labor (median 20, IQR 10–30 versus 17, IQR 6–30; p = 0.005). This association persisted after adjustment for confounders (incidence rate ratio 1.16, 95% CI 1.05–1.29; p = 0.004). Pain scores on the day of surgery were higher in women with intrapartum CD (difference 0.91, 95% CI 0.52–1.30; adj. p = <0.001) even after adjustment for confounders. Pain scores at other time points were not meaningfully different between the two groups.

Conclusion

Intrapartum CD is associated with worse pain on the day of surgery but not other time points. Opioid requirements following discharge were modestly increased following intrapartum CD.

Sex Differences, Sleep Disturbance and Risk of Persistent Pain Associated With Groin Hernia Surgery: A Nationwide Register-Based Cohort Study

Persistent pain after groin hernia repair is a major health problem. Sleep disturbance is associated with heightened pain sensitivity. The main objective of this study was to examine the role of sleep disturbance in the development and long-term maintenance of chronic postherniorrhaphy inguinal pain (CPIP), with exploration of sex differences. From 2012 to 2017, a national cohort of patients with prior groin hernia repair (n = 2084;45.8% females) were assessed for the development of CPIP 12 months after surgery. Patients then underwent long-term (median 5.0 years) follow-up to evaluate the contribution of sex and sleep disturbance on the maintenance of CPIP. Associations between pre- and postoperative sleep problems (assessed at long-term follow-up) and CPIP were tested using logistic regression. Females had higher rates of CPIP with negative impact on daily activities 12 months after surgery as compared to males (14.6 vs 9.2%, P < .0005), and were more likely to have moderate-severe CPIP in the long-term (3.1 vs 1.2%, P = .003). Preoperative sleep problems predicted development of CPIP 12 months after surgery (adjusted odds ratio [aOR] 1.76 [95%CI 1.26-2.46], P = .001) and CPIP in the long-term (aOR 2.20 [1.61-3.00] , P < .0001). CPIP was associated with insomnia and depression. Sleep disturbance may increase the risk for CPIP, and contribute to maintenance of postsurgical pain. PERSPECTIVE: Females are at heightened risk for CPIP as compared to males. Increased severity of pain symptoms are linked to poorer sleep and psychiatric morbidity. Given the robust associations between sleep disturbance and CPIP, interventions which consolidate and promote sleep, especially in females, may improve long-term pain control.

Preoperative sleep quality and adverse pain outcomes after total hip arthroplasty

BACKGROUND

Sleep disturbance is thought to aggravate acute postoperative pain. The influence of preoperative sleep problems on pain control in the long-term and development of chronic postsurgical pain is largely unknown.

METHODS

This prospective, observational study aimed to examine the links between preoperative sleep disturbance (Pittsburgh Sleep Quality Index, PSQI) and pain severity (Brief Pain Inventory, BPI) 6 months postoperative (primary outcome), objective measures of pain and postoperative pain control variables (secondary outcomes). Patients (n = 52) with disabling osteoarthritis (OA) pain undergoing total hip arthroplasty (THA) were included. Quantitative sensory testing (QST) was performed preoperatively on the day of surgery to evaluate pain objectively. Clinical data, as well as measures of sleep quality and pain, were obtained preoperatively and longitudinally over a 6-month period.

RESULTS

Preoperatively, sleep disturbance (i.e., PSQI score >5) occurred in 73.1% (n = 38) of THA patients, and pain severity was high (BPI pain severity 5.4 ± 1.3). Regression models, adjusting for relevant covariates, showed that preoperative PSQI score predicted pain severity 6 months postoperative (β = 0.091 (95% CI 0.001-0.181), p = .048, R²  = 0.35). Poor sleep quality was associated with increased pressure pain sensitivity and impaired endogenous pain inhibitory capacity (R² range 0.14-0.33, all p's < 0.04). Moreover, preoperative sleep disturbance predicted increased opioid treatment during the first 24 hr after surgery (unadjusted β = 0.009 (95% CI 0.002-0.015) mg/kg, p = .007, R²  = 0.15).

CONCLUSIONS

Preoperative sleep disturbance is prevalent in THA patients, is associated with objective measures of pain severity, and independently predicts immediate postoperative opioid treatment and poorer long-term pain control in patients who have undergone THA.

SIGNIFICANCE

Poor sleep quality and impaired sleep continuity are associated with heightened pain sensitivity, but previous work has not evaluated whether preoperative sleep problems impact long-term postoperative pain outcomes. Here, we show that sleep difficulties prior to total hip arthroplasty adversely predict postoperative pain control 6 months after surgery. Given sleep difficulties robustly predict pain outcomes, targeting and improving sleep may have salutary effects on postoperative pain reports and management.

The Effectiveness and Safety of Intravenous Dexmedetomidine of Different Concentrations Combined with Butorphanol for Post-Caesarean Section Analgesia: A Randomized Controlled Trial

Purpose

The present study aimed to determine the effectiveness of intravenous dexmedetomidine of different concentrations and to evaluate its maternal and neonatal safety when combined with butorphanol in parturients undergoing cesarean section.

Patients and Methods

A total of 114 parturients between 24 and 43 years of age, with singleton pregnancy who underwent elective cesarean section under epidural anesthesia, were randomly allocated to four groups: group C received 0.9% sodium chloride after delivery, followed by butorphanol (3 μg·kg^-1·h^-1); patients in groups D1, D2, and D3 received 0.5 μg·kg^-1·h^-1 dexmedetomidine after delivery, followed by butorphanol (3 μg·kg^-1·h^-1) combined with dexmedetomidine 0.03, 0.05, and 0.08 μg·kg^-1·h^-1, respectively. The primary outcome was the visual analogue scale (VAS) score at 6 h after delivery when patients were at rest. Secondary outcome measures included VAS after delivery when patients were on movement and uterine cramping, Ramsay sedation scale (RSS), relative infant dose (RID) of dexmedetomidine, satisfaction with analgesia after surgery and symptoms of CNS depression in neonates.

Results

There were no significant differences in patient characteristics among the groups (P > 0.05). The VAS at all timepoints after delivery in groups D2 and D3 were significantly lower than in groups C and D1 (P < 0.001). RSS scores were clearly higher in group D3 than in the other three groups at 6 h and 12 h (P < 0.0001). RID in groups D1, D2, and D3 was 0.171%, 0.197%, and 0.370%, respectively. Compared with group D1, RID was higher in group D3 (P = 0.0079). Degree of satisfaction with analgesia was higher in groups D2 and D3 (P < 0.005).

Conclusion

Continuous intravenous infusion of 0.05 μg·kg^-1·h^-1 dexmedetomidine combined with 3 μg·kg^-1·h^-1 butorphanol could be safely applied in healthy parturients with satisfactory analgesia after cesarean section without changes in sedation.

Relationships of sleep disturbance, intestinal microbiota, and postoperative pain in breast cancer patients: a prospective observational study

Purpose

Our study was designed to examine the possible relationship between gut microbiota, sleep disturbances, and acute postoperative pain.

Methods

Using 16S rRNA sequencing, we analyzed preoperative fecal samples from women undergoing breast cancer surgery. Preoperative sleep disturbance was evaluated with the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Peak and average pain at rest and movement were evaluated 24 h after surgery, using a numerical rating scale (NRS). Preoperative symptoms of depression and anxiety were assessed with the Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7), respectively. Inflammation was measured using white blood cell and neutrophil counts, together with platelet-lymphocyte ratio, and neutrophil-lymphocyte ratio.

Results

Preoperative sleep disturbance was associated with more severe acute postoperative pain. At the phylum level, women with poor sleep quality had higher relative abundance of Firmicutes (p = 0.021) and lower relative abundance of Bacteroidetes (p = 0.013). At the genus level, women with poor sleep quality harbored higher relative abundance of Acidaminococcus and lower relative abundance of several genera. The genus Alloprevotella was negatively associated with peak pain at movement during the first 24 h (r = − 0.592, p < 0.001). The genus Desulfovibrio was negatively associated with symptoms of anxiety (r = − 0.448, p = 0.006). However, partial correlations suggested that the relationship between Alloprevotella and peak pain at movement during the first 24 h was not statistically significant after controlling for sleep (r = − 0.134, p = 0.443).

Conclusion

These findings suggest that the changed gut microbiota may be involved in sleep-pain interaction and could be applied as a potential preventive method for postoperative pain.

Trial registration

The present clinical study has been registered on Chinese Clinical Trial Registry (www.chictr.org.cn); the clinical trial registration number is ChiCTR1900021730; the date of registration is March 7, 2019.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11325-020-02246-3.

Effect of thoracic paravertebral nerve block on the early postoperative rehabilitation in patients undergoing thoracoscopic radical lung cancer surgery

Objective

To evaluate the effect of thoracic paravertebral nerve block on early postoperative rehabilitation in patients undergoing radical thoracoscopic surgery for lung cancer.

Methods

Ninety patients scheduled for elective video-assisted thoracoscopic lobectomy of lung cancer were divided into 2 groups: the general anesthesia group (GA group, n = 45) and the TPVB group (TP group, n = 45). The primary outcome was the decline rate of the 6-min walking test (6MWT); the second outcomes were as follows: absolute value and the completion rate of 6MWT, postoperative analgesia deficiency and pain scores, oxycodone consumption, sleep quality, the incidence of postoperative pulmonary complications, and the hospital stay.

Results

Compared with the GA group, the TP group had a lower decline rate of the 6MWT on POD1 and POD2. The walking distance on POD1 and POD2 in the TP group was significantly longer than that in the GA group; the completion rate at POD1 in the TP group was higher than that in the GA group. The pain scores and oxycodone consumption at POD1 in the TP group were lower than the GA group. The sleep quality in the TP group was higher than the GA group.

Conclusions

TPVB can significantly improve postoperative rehabilitation in patients undergoing thoracoscopic radical lung cancer surgery, which is helpful for promoting the early recovery of patients.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1900026213. Registered 26 Sept. 2019, http://www.chictr.org.cn/showproj.aspx?proj=43733.

Risk of Postoperative Hyperalgesia in Adult Patients with Preoperative Poor Sleep Quality Undergoing Open-heart Valve Surgery

Purpose

Studies have reported that preoperative poor sleep quality could decrease the pain threshold in patients undergoing noncardiac surgery. However, the risk of postoperative hyperalgesia (HA) in cardiac surgery patients with preoperative poor sleep quality remains unclear.

Patients and Methods

We retrospectively collected clinical data from patients undergoing open-heart valve surgery between May 1 and October 31, 2019, in Fuwai Hospital (Beijing). We assessed preoperative sleep quality and postoperative pain severity using the Pittsburgh sleep quality index (PSQI) and numerical pain rating scale (NPRS), respectively. A PSQI of six or greater was considered to indicate poor sleep quality, and a NPRS of four or greater was considered to indicate HA. Multivariable logistic regression analysis was used to study the risk of postoperative HA in patients with preoperative poor sleep quality.

Results

We divided 214 eligible patients into two groups based on postoperative HA; HA group: n=61 (28.5%) and nonHA group: n=153 (71.5%). Compared with nonHA patients, patients with postoperative HA showed a higher percentage of history of smoking, 17 (11.1%) vs 15 (24.6%) and alcohol abuse, 5 (3.3%) vs 6 (9.8%), higher intraoperative dose of sufentanil (median, 1.02 vs 1.12 μg/kg/h), and longer duration of ventilation with tracheal catheter (median, 760 vs 934 min). Preoperative poor sleep quality was associated independently with an increased risk of postoperative HA (adjusted odds ratio [AOR]: 2.66; 95%CI: 1.31–5.39, P=0.007). Stratification by history of smoking revealed a stronger risk of postoperative HA in nonsmoking patients with preoperative poor sleep quality (AOR: 3.40; 95%CI: 1.51–7.66, P=0.003). No risk was found in patients who had history of smoking (AOR: 0.83; 95%CI: 0.14–4.75, P=0.832).

Conclusion

Preoperative poor sleep quality is an independent risk factor for postoperative HA in adult patients undergoing open-heart valve surgery who had no history of smoking.

Predicting Severity of Acute Pain After Cesarean Delivery: A Narrative Review

Cesarean delivery is one of the most common surgical procedures in the United States, with over 1.3 million performed annually. One-fifth of women who undergo cesarean delivery will experience severe pain in the acute postoperative period, increasing their risk of developing chronic pain and postpartum depression, and negatively impacting breastfeeding and newborn care. A growing body of research has investigated tools to predict which patients will experience more severe pain and have increased analgesic consumption after cesarean delivery. These include quantitative sensory testing, assessment of wound hyperalgesia, response to local anesthetic infiltration, and preoperative psychometric evaluations such as validated psychological questionnaires and simple screening tools. For this review, we searched MEDLINE, the Cochrane database, and Google Scholar to identify articles that evaluated the utility of various tools to predict severe pain and/or opioid consumption in the first 48 hours after cesarean delivery. Thirteen articles were included in the final review: 5 utilizing quantitative sensory testing, including patient responses to pressure, electrical, and thermal stimuli; 1 utilizing hyperalgesia testing; 1 using response to local anesthetic wound infiltration; 4 utilizing preoperative psychometric evaluations including the State-Trait Anxiety Inventory, the Pain Catastrophizing Scale, the Pittsburgh Sleep Quality Index, the Hospital Anxiety and Depression Scale, and simple questionnaires; and 2 utilizing a combination of quantitative sensory tests and psychometric evaluations. A number of modalities demonstrated statistically significant correlations with pain outcomes after cesarean delivery, but most correlations were weak to modest, and many modalities might not be clinically feasible. Response to local anesthetic infiltration and a tool using 3 simple questions enquiring about anxiety and anticipated pain and analgesic needs show potential for clinical use, but further studies are needed to evaluate the utility of these predictive tests in clinical practice.

Preoperative predictors of poor acute postoperative pain control: a systematic review and meta-analysis

OBJECTIVES

Inadequate postoperative pain control is common and is associated with poor clinical outcomes. This study aimed to identify preoperative predictors of poor postoperative pain control in adults undergoing inpatient surgery.

DESIGN

Systematic review and meta-analysis DATA SOURCES: MEDLINE, Embase, CINAHL and PsycINFO were searched through October 2017.

ELIGIBILITY CRITERIA

Studies in any language were included if they evaluated postoperative pain using a validated instrument in adults (≥18 years) and reported a measure of association between poor postoperative pain control (defined by study authors) and at least one preoperative predictor during the hospital stay.

DATA EXTRACTION AND SYNTHESIS

Two reviewers screened articles, extracted data and assessed study quality. Measures of association for each preoperative predictor were pooled using random effects models.

RESULTS

Thirty-three studies representing 53 362 patients were included in this review. Significant preoperative predictors of poor postoperative pain control included younger age (OR 1.18 [95% CI 1.05 to 1.32], number of studies, n=14), female sex (OR 1.29 [95% CI 1.17 to 1.43], n=20), smoking (OR 1.33 [95% CI 1.09 to 1.61], n=9), history of depressive symptoms (OR 1.71 [95% CI 1.32 to 2.22], n=8), history of anxiety symptoms (OR 1.22 [95% CI 1.09 to 1.36], n=10), sleep difficulties (OR 2.32 [95% CI 1.46 to 3.69], n=2), higher body mass index (OR 1.02 [95% CI 1.01 to 1.03], n=2), presence of preoperative pain (OR 1.21 [95% CI 1.10 to 1.32], n=13) and use of preoperative analgesia (OR 1.54 [95% CI 1.18 to 2.03], n=6). Pain catastrophising, American Society of Anesthesiologists status, chronic pain, marital status, socioeconomic status, education, surgical history, preoperative pressure pain tolerance and orthopaedic surgery (vs abdominal surgery) were not associated with increased odds of poor pain control. Study quality was generally high, although appropriate blinding of predictor during outcome ascertainment was often limited.

CONCLUSIONS

Nine predictors of poor postoperative pain control were identified. These should be recognised as potentially important factors when developing discipline-specific clinical care pathways to improve pain outcomes and to guide future surgical pain research.

PROSPERO REGISTRATION NUMBER

CRD42017080682.

Predictive value of SNOT-22 on additional opiate prescriptions after endoscopic sinus surgery

BACKGROUND

Endoscopic sinus surgery (ESS) is generally well tolerated, yet a subset of patients require an additional opiate prescription in the postoperative period. The purpose of this study was to quantify differences in both preoperative and immediate postoperative 22-item Sino-Nasal Outcome Test (SNOT-22) scores between patients with a single prescription and those requiring additional opiate prescriptions (AOPs).

METHODS

Patients undergoing ESS between November 2016 and August 2017 were reviewed retrospectively. The Medical and Controlled Substance Utilization Review and Evaluation System (CURES) records were reviewed; patients requiring AOP within 60 days after surgery were identified. The primary and secondary outcomes of interest were the association of baseline and first postoperative visit SNOT-22 total and domain scores with AOP.

RESULTS

A total of 121 patients were reviewed, 22 (18.2%) required AOP. Baseline SNOT-22 scores were higher in aggregate (58.7 ± 16.0 vs 46.1 ± 22.5) and ear/facial domain (11.4 ± 4.8 vs 8.5 ± 5.4) in the AOP group (p < 0.01). AOP patients also demonstrated higher scores across all SNOT-22 domains (p < 0.001) at the immediate preoperative visit. There was no difference in the absolute improvement between groups (15.5 ± 18.30 vs 12.3 ± 23.9, p = 0.54). AOP patients experienced less relative improvement (20.2% vs 34.8%, p < 0.05) and smaller mean effect size (0.57 vs 0.70, p < 0.001) after ESS.

CONCLUSION

Patients reporting increased ear and facial symptoms at baseline have an increased risk of additional opiate prescription after surgery; preoperative SNOT-22 scores may provide utility in identifying these patients. Subjects in both cohorts report symptomatic improvement after ESS; however, relative, not absolute, improvement in SNOT-22 scores is more predictive of AOP.