Mild, moderate, and severe pain in patients recovering from major abdominal surgery

Validation of the Korean version of defense and veterans pain rating scale for assessment of postoperative pain: a prospective observational cohort study

Background

The defense and veterans pain rating scale (DVPRS) is a pain assessment tool combining a numerical rating scale (NRS) with descriptive words, colors, and facial expressions. This study aimed to validate the Korean version of the DVPRS (K-DVPRS) for postoperative pain assessment.

Methods

This study included patients who underwent elective laparoscopic or robotic abdominal surgery. The original DVPRS was translated into Korean using a forward-backward method. Pain intensities at rest and during coughing were assessed at 24 and 48 hours postoperatively using the NRS and K-DVPRS, respectively. The EuroQol 5-Dimension 5-Level (EQ-5D-5L) questionnaire was also used. The validity, reliability, and responsiveness of the K-DVPRS were evaluated.

Results

Of the 174 patients screened, 150 were enrolled, and 148 completed the study. The K-DVPRS had strong convergent validity with the NRS at 24 and 48 hours postoperatively (ρ: 0.75 to 0.78, all P < 0.001). Construct validity was confirmed by significant differences in pain scores based on surgical extent and duration. The internal consistency was acceptable (Cronbach's alpha: 0.77 and 0.85 at 24 and 48 hours, respectively), and test-retest reliability at 24 hours was excellent (intraclass correlation coefficient: 0.90 at rest and 0.95 during coughing). Responsiveness, measured by Cliff's effect size, was high from preoperative to 24 hours postoperatively and moderate from 24 to 48 hours. At 48 hours, the K-DVPRS had stronger correlations with the EQ-5D-5L index and EQVAS than with the NRS.

Conclusions

The K-DVPRS is a valid, reliable, and responsive tool for assessing postoperative pain in Korean patients.

Risk Factors for Severe Pain and Impairment of Daily Life Activities after Cesarean Section-A Prospective Multi-Center Study of 11,932 Patients

Cesarean section (CS) is the most widely performed and one of the most painful surgeries. This study investigated postoperative pain after CS using patient-related outcomes (PROs) to identify risk factors for severe pain. The secondary outcome was to evaluate the influence of surgery indication (primary CS (PCS) vs. urgent CS (UCS)). This multi-center, prospective cohort study included data submitted to the pain registry "quality improvement in postoperative pain treatment" (QUIPS) between 2010 and 2020. In total, 11,932 patients were evaluated. Median of maximal pain was 7.0 (numeric rating scale (NRS) 0 to 10); 53.9% suffered from severe pain (NRS ≥ 7), this being related to impairment of mood, ambulation, deep breathing and sleep, as well as more vertigo, nausea and tiredness (p < 0.001). Distraction, relaxation, mobilization, having conversations, patient-controlled analgesia (PCA) and pain monitoring were shown to be protective for severe pain (p < 0.001). Maximal pain in PCS and UCS was similar, but UCS obtained more analgesics (p < 0.001), and experienced more impairment of ambulation (p < 0.001) and deep breathing (p < 0.05). Severe pain has a major effect on daily-life activities and recovery after CS, and depends on modifiable factors. More effort is needed to improve the quality of care after CS.

Post-total joint arthroplasty opioid prescribing practices vary widely and are not associated with opioid refill: an observational cohort study

INTRODUCTION

Optimized health system approaches to improving guideline-congruent care require evaluation of multilevel factors associated with prescribing practices and outcomes after total knee and hip arthroplasty.

MATERIALS AND METHODS

Electronic health data from patients who underwent a total knee or hip arthroplasty between January 2016-January 2020 in the Military Health System Data were retrospectively analyzed. A generalized linear mixed-effects model (GLMM) examined the relationship between fixed covariates, random effects, and the primary outcome (30-day opioid prescription refill).

RESULTS

In the sample (N = 9151, 65% knee, 35% hip), the median discharge morphine equivalent dose was 660 mg [450, 892] and varied across hospitals and several factors (e.g., joint, race and ethnicity, mental and chronic pain conditions, etc.). Probability of an opioid refill was higher in patients who underwent total knee arthroplasty, were white, had a chronic pain or mental health condition, had a lower age, and received a presurgical opioid prescription (all p < 0.01). Sex assigned in the medical record, hospital duration, discharge non-opioid prescription receipt, discharge morphine equivalent dose, and receipt of an opioid-only discharge prescription were not significantly associated with opioid refill.

CONCLUSION

In the present study, several patient-, care-, and hospital-level factors were associated with an increased probability of an opioid prescription refill within 30 days after arthroplasty. Future work is needed to identify optimal approaches to reduce unwarranted and inequitable healthcare variation within a patient-centered framework.

Predictive models for fentanyl dose requirement and postoperative pain using clinical and genetic factors in patients undergoing major breast surgery

ABSTRACT

Fentanyl exhibits interindividual variability in its dose requirement due to various nongenetic and genetic factors such as single nucleotide polymorphisms (SNPs). This study aims to develop and cross-validate robust predictive models for postoperative fentanyl analgesic requirement and other related outcomes in patients undergoing major breast surgery. Data regarding genotypes of 10 candidate SNPs, cold pain test (CPT) scores, pupillary response to fentanyl (PRF), and other common clinical characteristics were recorded from 257 patients undergoing major breast surgery. Predictive models for 24-hour fentanyl requirement, 24-hour pain scores, and time for first analgesic (TFA) in the postoperative period were developed using 4 different algorithms: generalised linear regression model, linear support vector machine learning (SVM-Linear), random forest (RF), and Bayesian regularised neural network. The variant genotype of OPRM1 (rs1799971) and higher CPT scores were associated with higher 24-hour postoperative fentanyl consumption, whereas higher PRF and history of hypertension were associated with lower fentanyl requirement. The variant allele of COMT (rs4680) and higher CPT scores were associated with 24-hour postoperative pain scores. The variant genotype of CTSG (rs2070697), higher intraoperative fentanyl use, and higher CPT scores were associated with significantly lower TFA. The predictive models for 24-hour postoperative fentanyl requirement, pain scores, and TFA had R-squared values of 0.313 (SVM-Linear), 0.434 (SVM-Linear), and 0.532 (RF), respectively. We have developed and cross-validated predictive models for 24-hour postoperative fentanyl requirement, 24-hour postoperative pain scores, and TFA with satisfactory performance characteristics and incorporated them in a novel web application.

Acute postoperative pain in 23 procedures of gynaecological surgery analysed in a prospective open registry study on risk factors and consequences for the patient

Effective perioperative pain management is essential for optimal patient recovery after surgery and reduces the risk of chronification. However, in clinical practice, perioperative analgesic treatment still needs to be improved and data availability for evidence-based procedure specific analgesic recommendations is insufficient. We aimed to identify procedures related with high pain scores, to evaluate the effect of higher pain intensity on patients and to define patient and intervention related risk factors for increased pain after standard gynaecological and obstetrical surgery. Therefore, we performed a prospective cross-sectional study based on the German registry for quality in postoperative pain (QUIPS). A cohort of 2508 patients receiving surgery between January 2011 and February 2016 in our tertiary referral centre (university departments of gynaecology and obstetrics, respectively) answered a validated pain questionnaire on the first postoperative day. Maximal pain intensity was measured by means of a 11-point numeric rating scale (NRS) and related to procedure, perioperative care as well as patient characteristics. The interventions with the highest reported pain scores were laparoscopic removal of ovarian cysts (NRS of 6.41 ± 2.12) and caesarean section (NRS of 6.98 ± 2.08). Factors associated with higher pain intensity were younger age (OR 1.75, 95% CI 1.65-1.99), chronic pain (OR 2.08, 95% CI 1.65-2.64) and surgery performed outside the regular day shift (OR 1.67, 95% CI 1.09-2.36). Shorter duration of surgery, peridural or local analgesic and preoperative sedation reduced postoperative pain. Patients reporting high pain scores (NRS ≥ 5) showed relevant impairment of daily activities and reduced satisfaction. Caesarean section and minimal invasive procedures were associated with the highest pain scores in the present ranking. Pain management of these procedures has to be reconsidered. Younger age, receiving surgery outside of the regular shifts, chronic pain and the surgical approach itself have a relevant influence on postoperative pain intensity. When reporting pain scores of 5 or more, patients were more likely to have perioperative complications like nausea or vomiting and to be impaired in mobilisation. Registry-based data are useful to identify patients, procedures and critical situations in daily clinical routine, which increase the risk for elevated post-intervention pain. Furthermore, it provides a database for evaluation of new pain management strategies.

The Prediction of Acute Postoperative Pain Based on Neural Oscillations Measured before the Surgery

Even with an improved understanding of pain mechanisms and advances in perioperative pain management, inadequately controlled postoperative pain remains. Predicting acute postoperative pain based on presurgery physiological measures could provide valuable insights into individualized, effective analgesic strategies, thus helping improve the analgesic efficacy. Considering the strong correlation between pain perception and neural oscillations, we hypothesize that acute postoperative pain could be predicted by neural oscillations measured shortly before the surgery. Here, we explored the relationship between neural oscillations 2 hours before the thoracoscopic surgery and the subjective intensity of acute postoperative pain. The spectral power density of resting-state beta and gamma band oscillations at the frontocentral region was significantly different between patients with different levels of acute postoperative pain (i.e., low pain vs. moderate/high pain). A positive correlation was also observed between the spectral power density of resting-state beta and gamma band oscillations and subjective reports of postoperative pain. Then, we predicted the level of acute postoperative pain based on features of neural oscillations using machine learning techniques, which achieved a prediction accuracy of 92.54% and a correlation coefficient between the real pain intensities and the predicted pain intensities of 0.84. Altogether, the prediction of acute postoperative pain based on neural oscillations measured before the surgery is feasible and could meet the clinical needs in the future for better control of postoperative pain and other unwanted negative effects. The study was registered on the Clinical Trial Registry (https://clinicaltrials.gov/ct2/show/NCT03761576?term=NCT03761576&draw=2&rank=1) with the registration number NCT03761576.

Objective postoperative pain assessment using incentive spirometry values: a prospective observational study

Aim: Determine if incentive spirometry (IS) values correlate with postoperative pain control. Design: Prospective observational study. Setting & participants: A total of 100 patients undergoing major abdominal procedures at the University of North Carolina Medical Center. Interventions: Patients studied as a single cohort. All patients received thoracic epidural analgesia preoperatively. Outcome: Preoperative and daily postoperative numeric pain scores, subjective pain description and IS values were collected for all patients. Results: There was a strong correlation with IS values relative to baseline for both the numeric pain scores (p < 0.0001), postoperative day (p < 0.0001) and the subjective pain score (p < 0.0007). Conclusion: IS values are an objective surrogate data point for pain control after surgery, particularly when followed over time and compared with a preoperative baseline value.

Cut-off points between pain intensities of the postoperative pain using receiver operating characteristic (ROC) curves

Background

Pain assessment and management are important in postoperative circumstances as overdosing of opioids can induce respiratory depression and critical consequences. We aimed this study to check the reliability of commonly used pain scales in a postoperative setting among Korean adults. We also intended to determine cut-off points of pain scores between mild and moderate pain and between moderate and severe pain by which can help to decide to use pain medication.

Methods

A total of 180 adult patients undergoing elective non-cardiac surgery were included. Postoperative pain intensity was rated with a visual analog scale (VAS), numeric rating scale (NRS), faces pain scale revised (FPS-R), and verbal rating scale (VRS). The VRS rated pain according to four grades: none, mild, moderate, and severe. Pain assessments were performed twice: when the patients were alert enough to communicate after arrival at the postoperative care unit (PACU) and 30 min after arrival at the PACU. The levels of agreement among the scores were evaluated using intraclass correlation coefficients (ICCs). The cut-off points were determined by receiver operating characteristic curves.

Results

The ICCs among the VAS, NRS, and FPS-R were consistently high (0.839–0.945). The pain categories were as follow: mild ≦ 5.3 / moderate 5.4 ~ 7.1 /severe ≧ 7.2 in VAS, mild ≦ 5 / moderate 6 ~ 7 / severe ≧ 8 in NRS, mild ≦ 4 / moderate 6 / severe 8 and 10 in FPS-R. The cut-off points for analgesics request were VAS ≧ 5.5, NRS ≧ 6, FPS-R ≧ 6, and VRS ≧ 2 (moderate or severe pain).

Conclusions

During the immediate postoperative period, VAS, NRS, and FPS-R were well correlated. The boundary between mild and moderate pain was around five on 10-point scales, and it corresponded to the cut-off point of analgesic request. Healthcare providers should consider VRS and other patient-specific signs to avoid undertreatment of pain or overdosing of pain medication.

Factors Influencing Satisfaction with Patient-Controlled Analgesia Among Postoperative Patients Using a Generalized Ordinal Logistic Regression Model

PURPOSE

The purpose of this study was to identify the factors affecting the satisfaction with patient-controlled analgesia (PCA) of patients using a generalized ordinal logistic regression model and to evaluate the difference in results of the ordinal regression from those of binary regression.

METHODS

The study design involved secondary analysis of electronic medical records from a single tertiary care hospital in Seoul, Korea. It included 2,409 patients treated with PCA for postoperative pain management after open or laparoscopic abdominal surgery. Binary logistic regression and generalized ordinal logistic regression were used to identify factors affecting satisfaction.

RESULTS

Binary logistic regression analysis showed that there was insufficient information for analysis. Generalized ordinal logistic regression revealed that sex, age, pain, PCA usage, and side-effects were common factors affecting PCA satisfaction. However, the effect of some factors affecting PCA satisfaction differed with the level of satisfaction. In open surgery patients, the effect of pain at 6 hours after surgery was significantly greater in the group with lower satisfaction. While, in the laparoscopic surgery patients, the effect of pain at 6-24 hours after surgery was significantly greater in the group with lower satisfaction.

CONCLUSION

Generalized logistic regression may be an appropriate statistical method for analyzing ordinal data. Degree of postoperative pain and assessment interval are the most important factors associated with PCA satisfaction. Because the factors affecting PCA satisfaction were different for the two types of abdominal surgeries, customizing PCA to individual patients may potentially improve pain management and consequently increase PCA satisfaction.

Postoperative pain after colorectal surgery

PURPOSE

Postoperative pain is a keystone in perioperative programs, as pain negatively impacts recovery. This study aimed to evaluate pain after elective colorectal surgery and to identify risk factors for postoperative pain.

METHODS

This prospective cohort study comprised consecutive patients undergoing elective colorectal surgery within the Enhanced Recovery after Surgery (ERAS) perioperative program between March 2013 and April 2017. The numeric rating scale (NRS) was used to estimate maximum pain. Logistic regression was used to model associations with the type of surgery, age, gender, and comorbidities.

RESULTS

The cohort comprised 434 of 459 eligible patients. On the day of surgery to postoperative day 3, 50-64% of patients reported moderate to severe pain (NRS 4-10). Postoperative pain was similar for open and minimally invasive rectal surgery, while patients undergoing minimally invasive colonic surgery experienced more pain on the day of surgery and less pain on postoperative days 2 and 3 vs. open colonic surgery. Younger age was associated with more pain every postoperative day and by 0.7 NRS/10 years (95% CI 0.5-0.9, P < 0.001) on the day of surgery, while having diabetes type 2 was associated with less postoperative pain by - 1.3 NRS (95% CI - 2.4 to - 0.2) on the day of surgery.

CONCLUSIONS

The majority, and young patients in particular, experience moderate to severe pain after open and minimally invasive colorectal surgery, despite following ERAS perioperative program. There is a need for effective and individualized analgesia after colorectal surgery, since the individual pain response to surgery is difficult to predict.

Disability after major abdominal surgery: determinants of recovery of walking ability in elderly patients

BACKGROUND

Increased life expectancy and improved surgical techniques have led to a sharp rise in healthcare resource consumption by older patients. In these patients early recovery of walking ability after abdominal surgery may shorten length of hospital stay and reduce overall healthcare costs, but it is important to understand what factors determine this recovery.

AIM

To assess preoperative and postoperative determinants of walking ability recovery after major abdominal surgery in older patients.

DESIGN

Prospective observational study.

SETTING

General Surgery Unit.

POPULATION

The study included 327 consecutive older inpatients who underwent major acute-care abdominal surgery.

METHODS

Data on demographic characteristics, diagnosis, comorbidities defined by Charlson Comorbidity Index (CCI), preoperative walking ability, and early postoperative physical deconditioning (PPDS) were gathered. All patients underwent an individually-tailored rehabilitation program. At discharge, pain (by a Visual Analogue Scale, VAS-pain, 0-10), transfers and walking ability were assessed. Number of rehabilitation sessions attended and discharge setting were recorded.

RESULTS

Of 320 patients included in the analysis (7 died), 72% had CCI>5, signifying presence of >1 comorbidities. Before hospitalization, 79% of patients were completely independent in walking at home, 12% needed assistive devices or direct assistance from the caregiver, and 9% were unable to walk. Complex postoperative physical deconditioning was detected in 25%. At discharge, most patients (87%) had achieved their rehabilitative goal and returned home. Only PPDS and VAS-pain were able to predict both walking ability and the discharge setting, PPDS alone showing adequate sensitivity (82%) and specificity (70%).

CONCLUSIONS

PPDS was the sole early postoperative predictor of recovery of walking ability and the discharge setting. Pain therapy might be a key factor influencing the postoperative functional decline. Age and severity of preoperative comorbidities seem not important determinants of functional decline in older surgical patients.

CLINICAL REHABILITATION IMPACT

An early postoperative assessment of physical deconditioning might be able to predict the walking ability at discharge (hence, the discharge setting), in older patients undergoing major surgery.

Endogenous Opiates and Behavior: 2015

This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.

The effect of using an abdominal binder on postoperative gastrointestinal function, mobilization, pulmonary function, and pain in patients undergoing major abdominal surgery: A randomized controlled trial

BACKGROUND

Evidence on the effectiveness of using a binder following abdominal surgery and its effect on gastrointestinal function, mobilization, pulmonary function, and pain is currently unclear.

OBJECTIVE

The purpose of this study is to determine the effect of abdominal binder usage on gastrointestinal function, mobilization, pulmonary function, and postoperative pain in patients undergoing major abdominal surgery.

DESIGN

This research was conducted as a randomized controlled trial.

SETTINGS

The study was conducted at the Department of General Surgery at a military education and research hospital in Ankara, Turkey, between September 2013 and April 2014.

PARTICIPANTS

104 patients were assessed for eligibility. The study was conducted on 84 eligible patients.

METHODS

The study sample consisted of 84 patients who underwent effective major abdominal surgery. The patients were randomized into two groups, the intervention group, which used an abdominal binder and the control group, which did not. Gastrointestinal function, mobilization, pulmonary function, and the pain status of both groups were evaluated on the first, fourth, and seventh days before and after surgery, and the intergroup results were compared.

RESULTS

No significant difference was found between the two groups in terms of gastrointestinal and pulmonary function on the first, fourth, and seventh days following surgery (p>0.05). A comparative assessment of mobility by walking distance showed that patients in the intervention group were able to walk further on the fourth [mean (SD); 221.19 (69.08) m] and seventh [227.85 (60.02) m] days after surgery (p=0.003, p<0.001). There were differences in the acute pain status between patients in both groups (p<0.05). On the first [mean (SD); 8.80 (5.03)], fourth [4.83 (2.78)], and seventh [3.09 (3.17)] days after surgery, the sensory sub-scale pain scores were higher in the control group (p<0.001). On the first [mean (SD); 10.16 (6.14)], fourth [5.28 (3.52)], and seventh [3.30 (3.51)] days after surgery the total pain scores were higher in the control group (p<0.001). The visual analogue scale scores were also higher in the control group on the first [mean (SD) 6.26 (1.86)], fourth [4.50 (2.10)], and seventh [3.04 (2.43)] days after surgery (p<0.001).

CONCLUSION

The study's findings reveal that the use of an abdominal binder does not have any effect on postoperative gastrointestinal and pulmonary function. However, an abdominal binder increases patient mobility soon after surgery. There was also a measurable effect on pain, with lower scores reported by patients who used an abdominal binder after any exercise or activity. These results indicate that the use of a routine abdominal binder is helpful for patients undergoing major abdominal surgery.