Challenges in the optimisation of post-operative pain management with opioids in obese patients: a literature review. Obes Surg. 2013;23:1458-1475. [PMID: 23700237 DOI: 10.1007/s11695-013-0998-8]

The Effect of Obesity on Postoperative Analgesia Practices and Complications Following Endoscopic Sinus Surgery: A Propensity Score-Matched Cohort Study

BACKGROUND

Despite growing concern regarding over-prescription of narcotic pain medication following ambulatory surgery, little is known about the analgesic prescribing practices following endoscopic sinus surgery (ESS) in obese patients in comparison to non-obese patients.

OBJECTIVE

To compare the rates of opioid versus non-opioid prescriptions, the need for steroids, and post-operative adverse events between obese and non-obese adult patients undergoing ESS.

METHODS

Using TriNetX Live database, we identified all patients aged ≥18 years who underwent ESS (n = 1303) between 2014 and 2022 across several healthcare institutions across the state of Tennessee. We 1:1 propensity score-matched obese (BMI ≥ 30 kg/m2) and non-obese (18.5 kg/m2 ≤ BMI < 30 kg/m2) cohorts for age, gender, race, and comorbidities including asthma, nicotine dependence, and sleep apnea. Rates of prescriptions and post-operative adverse events between cohorts were analyzed using risk ratios (RR) and confidence intervals (CI).

RESULTS

A toal of 532 obese patients were compared to 532 propensity score-matched non-obese patients in the first 14 post-operative days following ESS. The obese cohort was significantly more likely to be prescribed analgesics generally (RR = 1.72; 95% CI = 1.20-2.47), non-opioid analgesics (RR = 1.73; 95% CI = 1.19-2.50), and opioid analgesics (RR = 1.64; 95% CI = 1.14-2.36) than non-obese patients. There was no difference in rates of antibiotic or antiemetic prescription, prednisone/methylprednisolone, dexamethasone, ED visits, critical care service, epistaxis, transfusion, anemia, revision sinus surgery, mechanical ventilation, CPAP, or inhalation airway treatments.

CONCLUSION

Obese patients undergoing ESS were significantly more likely to be prescribed non-opioid and opioid analgesia in the first 14 days post-operatively compared to non-obese patients. There were no differences in post-operative adverse events or other prescriptions. Otolaryngologists should be aware that obese patients are at increased risk of opioid induced airway obstruction and steroid induced hyperglycemia, especially in patients with comorbid sleep apnea or diabetes. Emphasis on non-opioid analgesics and multimodal pain management should be advocated for this population.

Efficacy of Erector Spinae Plane Block on Analgesic Outcomes in Patients Undergoing Metabolic Surgery: A Meta-Analysis of Randomized Controlled Trials

This meta-analysis evaluated the analgesic efficacy of erector spinae plane block (ESPB) in metabolic surgery through analysis of ten randomized controlled trials (786 patients). ESPB demonstrated superior pain control compared to placebo from 2-12 h postoperatively, with peak effect at 6 h and sustained movement-related pain reduction through 24 h. ESPB showed comparable analgesic efficacy to other nerve blocks within 24 h postoperatively. The technique significantly reduced intraoperative and postoperative opioid consumption, extended time to first analgesic requirement, and decreased rescue analgesia needs. Additionally, ESPB recipients experienced reduced postoperative nausea and vomiting and shorter hospital stays. These findings support ESPB as an effective component of multimodal analgesia protocols for metabolic surgery, though standardization of techniques and long-term outcome studies are needed.

The association of obesity with post-cesarean inpatient opioid consumption

BACKGROUND

Obesity and prescription opioid misuse are important public health concerns in the United States. A common intersection occurs when women with obesity undergo cesarean birth and receive narcotic medications for postpartum pain.

OBJECTIVE

To examine the association between obesity and inpatient opioid use after cesarean birth.

METHODS

A retrospective cohort study of patients that underwent cesarean birth in 2015-2018. Primary outcome was post-cesarean delivery opioid consumption starting 24 h after delivery measured as morphine milliequivalents per hour (MME/h). Secondary outcome was MME/h consumption in the highest quartile of all subjects. Opioid consumption was compared between three BMI groups: non-obese BMI 18.5-29.9 kg/m2; obese BMI 30.0-39.9 kg/m2; and morbidly obese BMI ≥ 40.0 kg/m2 using univariable and multivariable analyses.

RESULTS

Of 1620 patients meeting inclusion criteria, 496 (30.6%) were in the non-obese group, 753 (46.5%) were in the obese group, and 371 (22.9%) were in the morbidly obese group. In the univariate analysis, patients with obesity and morbid obesity required higher MME/h than patients in the non-obese group [1.3 MME/h (IQR 0.1, 2.4) vs. 1.6 MME/h (IQR 0.5, 2.8) vs. 1.8 MME/h (IQR 0.8, 2.9), for non-obese, obese, and morbidly obese groups respectively, p < 0.001]. In the multivariable analysis, this association did not persist. In contrast, subjects in the obese and morbidly obese groups were more likely to be in the highest quartile of MME/h opioid consumption compared with those in the non-obese group (23.5% vs. 48.1% vs. 28.4%, p < 0.001, respectively); with aOR 1.42 (95% CI 1.07-1.89, p = 0.016) and aOR 1.60 (95% CI 1.16-2.22, p = 0.005) for patients with obesity and morbid obesity, respectively.

CONCLUSION

Maternal obesity was not associated with higher hourly MME consumption during inpatient stay after cesarean birth. However, patients with obesity and morbid obesity were significantly more likely to be in the top quartile of MME hourly consumption.

Surgical transversus abdominis plane block with liposomal bupivacaine at cesarean: a pilot randomized trial

BACKGROUND

Postcesarean pain control is challenging. In addition to intrathecal morphine, recent studies have shown that liposomal bupivacaine administered via conventional transversus abdominis plane block reduces postcesarean opioid use. However, whether the administration of liposomal bupivacaine via a surgical approach also reduces opioid use is unknown.

OBJECTIVE

This study aimed to investigate whether the administration of liposomal bupivacaine via surgical transversus abdominis plane block (TAP block) reduces the cumulative dose of opioids administered in the first 48 hours after cesarean delivery among participants who also receive intrathecal morphine.

STUDY DESIGN

This was a pilot single-blind randomized controlled trial of 60 parturients undergoing cesarean delivery at a community tertiary referral hospital staffed by academic physicians. Immediately before fascial closure during cesarean delivery, a total of 80 mL of dilute bupivacaine plus liposomal bupivacaine or dilute bupivacaine alone was administered via surgical transversus abdominis plane block (40 mL on each side). The primary outcome was a median cumulative opioid dose received within the first 48 hours after cesarean delivery measured in morphine milligram equivalents. In addition, opioid use at other time points, pain scores, and participant satisfaction were assessed. A sample size of 60 was determined to be adequate to inform a potential future adequately powered randomized trial. The primary outcome of morphine milligram equivalents and pain scores were compared using a Wilcoxon rank-sum test.

RESULTS

Between October 11, 2021, and August 29, 2022, 60 participants were randomized and analyzed: 31 were allocated to liposomal bupivacaine plus regular bupivacaine (intervention group), and 29 were allocated to regular bupivacaine alone (control group). Participants allocated to the intervention group used a median cumulative dose of 2 morphine milligram equivalents of opioids (interquartile range, 0-24) in the first 48 hours compared with 8 morphine milligram equivalents (interquartile range, 0-40) among participants allocated to the control group (P=.236). The percentage of participants who used ≤15 morphine milligram equivalents of opioids was 61% in the intervention arm and 41% in the control arm (P=.123), and the percentage who used zero opioids was 45% in the intervention arm and 34% in the control arm (P=.399). The total number of opioid pills prescribed at discharge was fewer in the intervention arm than in the control arm (P=.029). Patient satisfaction with the intervention group and control group was similar.

CONCLUSION

Our pilot study suggests that liposomal bupivacaine administered via surgical transversus abdominis plane block is worth critical evaluation as an adjunctive analgesic modality in an adequately powered randomized trial.

The effect of body mass index on thoracic paravertebral block analgesia after video-assisted thoracoscopic surgery; a prospective interventional study

BACKGROUND

To investigate the effects of body mass index (BMI) on intensity postoperative pain in patients who underwent thoracic paravertebral block (TPVB) for postoperative analgesia after video-assissted thoracoscopic surgery (VATS).

METHODS

Patients aged 18-80 years, ASA I-III, and BMI 18-40 kg/m2 who underwent elective VATS were included in the study. The patients were divided into 3 groups according to their BMI levels. TPVB was performed under ultrasound-guidance at the fifth thoracic vertebrae, and 30 ml of 0.25% bupivacaine was injected. The patient-controlled analgesia (PCA) was performed by using morphine and multimodal analgesia was performed. As a rescue analgesic agent, 0.5 mg/kg tramadol was given to patients intravenously when a score of visual analog scale (VAS) at rest was ≥ 4. The primary outcome was determined as VAS scores at rest and cough. Secondary outcomes were determined as postoperative morphine consumption, additional analgesic requirement, and side effects.

RESULTS

The post-hoc test revealed that the VAS resting scores at the 4th hour (p: 0.007), 12th hour (p: 0.014), and 48th hour (p: 0.002) were statistically significantly lower in Group I compared to Group II. Additionally, VAS resting scores were also statistically significantly lower in Group I compared to Group III at all time points (p < 0.05). Similarly, the post-hoc test indicated that the VAS coughing scores at the 4th hour (p: 0.023), 12th hour (p: 0.011), and 48th hour (p: 0.019) were statistically significantly lower in Group I compared to Group II. Moreover, VAS coughing scores were statistically significantly lower in Group I compared to Group III at all time points (p < 0.001). Furthermore, there were statistically significant differences in terms of additional analgesic use between the groups (p: 0.001). Additionally, there was a statistically significant difference in terms of morphine consumption via PCA and morphine milligram equivalent consumption between the groups (p < 0.001).

CONCLUSIONS

Higher postoperative VAS scores with TPVB applied in obese patients and the consequent increase in additional analgesics and complications require more specific postoperative management in this patient group.

Opioid Analgesics after Bariatric Surgery: A Scoping Review to Evaluate Physiological Risk Factors for Opioid-Related Harm

The persisting use of opioids following bariatric surgery has emerged as a prevalent complication, heightening the probability of opioid-related harm (ORM), such as opioid-related fatalities and prescription opioid use disorder (OUD). A comprehensive review of PubMed literature from 1990 to 2023 was conducted to pinpoint physiological influences on postoperative ORM. As a result, we found that patients undertaking bariatric operations often exhibit an inherently higher risk for substance use disorders, likely attributable to genetic predisposition and related neurobiological changes that engender obesity and addiction-like tendencies. Furthermore, chronic pain is a common post-bariatric surgery complaint, and the surgical type impacts opioid needs, with increased long-term opioid use after surgeries. Additionally, the subjective nature of pain perception in patients with obesity can distort pain reporting and the corresponding opioid prescription both before and after surgery. Furthermore, the postoperative alterations to the gastrointestinal structure can affect the microbiome and opioid absorption rates, resulting in fluctuating systemic exposure to orally ingested opioids. The prospect of ORM development post-bariatric surgery appears amplified due to a preexisting susceptibility to addictive habits, surgically induced pain, modified gut-brain interaction and pain management and the changed pharmacokinetics post-surgery. Further research is warranted to clarify these potential risk variables for ORM, specifically OUD, in the bariatric population.

Efficacy and Safety of Gabapentin on Postoperative Pain Management After Bariatric Surgery: A Systematic Review and Meta-Analysis

PURPOSE

Examine the efficacy and safety of perioperative gabapentin in bariatric surgical patients.

DESIGN

Systematic Review and Meta-analysis.

METHODS

An exhaustive search was conducted using PubMed, Cochrane Library, MEDLINE, CINAHL, Google Scholar, and other gray literature. Only randomized controlled trials evaluating the use of gabapentin in bariatric surgery were included. Risk ratio (RR) and mean difference (MD) were used to estimate outcomes with suitable effect models. Quality of evidence was assessed using the Risk of Bias and GRADE system.

FINDINGS

Four trials consisting of 283 patients were analyzed. The use of gabapentin significantly lowered the cumulative pain score in the first 24 hours after surgery by an average of 1.04 (MD, -1.04; 95% CI, -1.45 to -0.63; P < .00001). Gabapentin also reduced the overall morphine equivalent consumption by 7.89 mg (MD, -7.89; 95% CI, -13.56 to -2.2; P = .006). However, gabapentin did not affect the incidence of PONV (RR, 0.61; 95% CI, 0.38-1.00; P = .05), somnolence (RR, 1.25; 95% CI, 0.57-2.73; P = .57), dizziness (RR, 1.01; 95% CI, 0.40-2.54; P = .99), and headache (RR, 0.76; 95% CI, 0.25-2.30; P = .62). Substantial heterogeneity, imprecision of the effect size, and potential publication bias were limitations of this review.

CONCLUSIONS

The use of gabapentin is effective in the management of postoperative pain in bariatric surgery. However, there is limited data regarding the opioid-sparing effect and adverse effect profiles of gabapentin in the bariatric surgical population.

Efficacy and Safety of Parenteral Injection of an Extended Release κ-receptor Opioid Sebacoyl Dinalbuphine Ester for Acute and Chronic Pain After Laparoscopic Bariatric Surgery: a Randomized, Placebo-Controlled, Double-Blind Trial

PURPOSE

μ-receptor opioids are associated with unwanted gastrointestinal side effects and respiratory depression. A long-acting non-μ-receptor parenteral opioid is not currently available for management of acute and chronic postsurgical pain (CPSP). This double-blind clinical trial tested an extended-release κ-receptor agonist, sebacoyl dinalbuphine ester (SDE, Naldebain®) for management of surgical pain after laparoscopic bariatric surgery.

MATERIALS AND METHODS

Patients were randomly assigned to receive a single intramuscular injection of SDE (150 mg, n = 30) or vehicle solution (n = 30) at > 12 h before surgery. All patients received standard perioperative multimodal analgesia (MMA). The primary endpoint was the pain intensity in the beginning 7 days after operation. The secondary endpoints were adverse reactions up to 7 days and incidence of CPSP at 3 months after surgery.

RESULTS

Compared with placebos, the area under curves of visual analog scale (VAS) for 0-48 h after operation were significantly reduced in SDE group (143.3 ± 65.4 and 105.9 ± 36.3, P = 0.025). There were significantly fewer patients in the SDE group who had moderate-to-severe pain (VAS ≥ 4) (16.7% vs 50%; P = 0.012) at postoperative 48 h. Pain intensities were similar between the two groups at 72 h and 7 days postoperatively. The incidence of CPSP at 3 months was not different. SDE did not increase drug-related systemic adverse events.

CONCLUSION

In addition to the standard perioperative MMA, a single-dose injection of long-acting κ-receptor agonist SDE provides significantly better pain management for 48 h following laparoscopic bariatric surgery. A long-acting κ-receptor agonist opioid could improve in-hospital pain management and potentiate early discharge after operation without increasing drug-related systemic complications.

Subcostal transversus abdominis plane block for postoperative analgesia in liver transplant recipients: a before-and-after study

INTRODUCTION

Postoperative pain management after orthotopic liver transplantation is complex due to impaired liver function and frequent acute kidney dysfunction. Subcostal transversus abdominis plane (TAP) block may be of interest in this population. The aim of this study was to evaluate the impact of subcostal TAP block on opioid consumption after liver transplantation.

METHODS

We conducted a before-and-after single center study. During the first period, we included patients whom did not receive an analgesic TAP block. During the second period, we included those with bilateral ultrasound-guided subcostal TAP block (20 mL ropivacaïne 0.2% each side). Patients requiring sedation within 48 hours of surgery as well as patients with combined liver and kidney transplants or skin-only closures were excluded. The primary outcome was cumulative oral morphine consumption within 48 hours after surgery. Secondary outcomes included pain scores and TAP block-related complications.

RESULTS

A total of 132 patients were included in the non-TAP block group and 78 patients in the TAP block group. The median oral morphine equivalent consumption (IQR) within 48 hours following surgery was 74 mg (39; 112) for the non-TAP block group and 50 mg (20; 80) for the TAP block group (p<0.001). There was no difference in pain scores between the two groups. No complications related to the TAP block were reported.

CONCLUSION

Subcostal TAP block appears to have a small opioid reducing effect after orthotopic liver transplantation surgery.

The effects of body mass index on postoperative pain in patients undergoing thoracic paravertebral block after video-assisted thoracoscopic surgery: A retrospective analysis

Aim: Postoperative pain is an important problem in patients undergoing video-assisted thoracic surgery (VATS). Thoracic paravertebral block (TPVB) is among the commonly used techniques for pain control after VATS. Despite the analgesic methods applied, the desired level of pain control can not be achieved in all patients. Therefore, clinicians and researchers are interested in factors affecting postoperative pain. One factor is the relationship between postoperative pain and body mass index (BMI). Although it has been reported that acute or chronic pain is more common in the general population with a BMI, the relationship between postoperative pain and BMI is still controversial. This study aims to investigate the effects of BMI on postoperative pain in patients who underwent TPVB in the treatment of pain after VATS. Material and Method: Patients who had elective VATS and TPVB were included in the study. Patients who underwent TPVB with ultrasonography (USG) and postoperative intravenous (iv) morphine patient-control-analgesia (PCA) for postoperative analgesia were divided into three groups according to BMI. Group-I BMI: 18-24.99 kg/m2, Group-II BMI: 25-29.9 kg/m2, Group-III BMI: 30-40 kg/m2. Results: 146 patients were included in the study. There was no significant difference between the postoperative 30th minute, 1st hour, 6th hour, 12th hour, and 24th-hour VAS values of the patients in Group-I, Group-II, and Group-III. There was no statistically significant difference in terms of morphine consumption, additional analgesic requirement, and complications in all three groups. Conclusion: It was determined that there was no relationship between BMI and postoperative pain scores in the first 24 hours in patients who underwent TPVB after VATS. In addition, it was determined that postoperative morphine consumption and additional analgesic needs were not associated with BMI. Effective pain control can be achieved in all patients, regardless of BMI, with effective peripheral nerve blocks and analgesics using practical imaging techniques such as USG.

Postoperative Respiratory Compromise following Cesarean Birth: The Impact of Obesity and Systemic Opioids

Objective  The aim of this study was to measure the effect of obesity and systemic opioids on respiratory events within the first 24 hours following cesarean. Methods  Opioid-naive women undergoing cesarean between January 2016 and December 2017 were included in this retrospective cohort study. The primary outcome was the proportion of women experiencing at least one composite respiratory outcome (oxygen saturation less than 95% lasting 30+ seconds or need for respiratory support) within 24 hours of cesarean. The impact of obesity and total systemic opioid dose in 24 hours (measured in morphine milligram equivalents [MMEs]) on the composite respiratory compromise outcome were evaluated. Results  Of 2,230 cesarean births, 790 women had at least one composite respiratory event. Predictors of the composite respiratory outcome included body mass index (BMI) as a continuous variable (odds ratio = 1.063 for every one unit increase in BMI [95% confidence interval (CI): 1.021-1.108], p  = 0.003), and MME (odds ratio = 1.005 [95% CI: 1.002-1.008], p  = 0.003), adjusting for magnesium sulfate use. The interaction between obesity and opioid dose demonstrated an odds ratio of 1.000 (95% CI: 0.999-1.000, p  = 0.030). Conclusion  The proportion of women experiencing respiratory events following cesarean birth increases with the degree of obesity and opioid dose. Key Points Respiratory events increase with obesity.Respiratory events increase with systemic opioid use.Odds ratio of respiratory events is 1.063/unit BMI increase.

Patient and in-hospital predictors of post-discharge opioid utilization: Individualizing prescribing after radical prostatectomy based on the ORIOLES initiative

OBJECTIVE

Judicious opioid stewardship would match each patient's prescription to their true medical necessity. However, most prescribing paradigms apply preset quantities and clinical judgment without objective data to predict individual use. We evaluated individual patient and in-hospital parameters as predictors of post-discharge opioid utilization after radical prostatectomy (RP) to provide evidence-based guidance for individualized prescribing.

METHODS

A prospective cohort of patients who underwent open or robotic RP were followed in the Opioid Reduction Intervention for Open, Laparoscopic, and Endoscopic Surgery (ORIOLES) initiative. Baseline demographics, in-hospital parameters, and inpatient and post-discharge pain medication utilization were tabulated. Opioid medications were converted to oral morphine equivalents (OMEQ). Predictive factors for post-discharge opioid utilization were analyzed by univariable and multivariable linear regression, adjusting for opioid reduction interventions performed in ORIOLES.

RESULTS

Of 443 patients, 102 underwent open and 341 underwent robotic RP. The factors most strongly associated with post-discharge opioid utilization included inpatient opioid utilization in the final 12 hours before discharge (+39.6 post-discharge OMEQ if inpatient OMEQ was >15 vs. 0), maximum patient-reported pain score (range 0-10) in the 12 hours before discharge (+27.6 OMEQ for pain score ≥6 vs. ≤1), preoperative opioid use (+76.2 OMEQ), and body mass index (BMI; +1.4 OMEQ per 1 kg/m²). A final predictive calculator to guide post-discharge opioid prescribing was constructed.

CONCLUSIONS

Following RP, inpatient opioid use, patient-reported pain scores, prior opioid use, and BMI are correlated with post-discharge opioid utilization. These data can help guide individualized opioid prescribing to reduce risks of both overprescribing and underprescribing.

Association of Physical Therapy Interventions With Long-term Opioid Use After Total Knee Replacement

IMPORTANCE

Many individuals who undergo total knee replacement (TKR) become long-term opioid users after TKR. Associations of physical therapy (PT) interventions before or after TKR with long-term use of opioids are not known.

OBJECTIVES

To evaluate associations of PT interventions before and after TKR with long-term opioid use after TKR.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from the OptumLabs Data Warehouse on 67 322 individuals aged 40 years or older who underwent TKR from January 1, 2001, to December 31, 2016, stratified by history of opioid use. The analyses for the study included data from January 1, 1999, to December 31, 2018.

EXPOSURES

Any PT interventions within 90 days before or after TKR, post-TKR PT dose as number of sessions (ie, 1-5, 6-12, and ≥13 sessions), post-TKR PT timing as number of days to initiation of care (ie, <30 days, 31-60 days, or 61-90 days after TKR), and post-TKR PT type (ie, active vs passive).

MAIN OUTCOMES AND MEASURES

The association of pre- and post-TKR PT with risk of long-term opioid use occurring more than 90 days after TKR was assessed using logistic regression while adjusting for confounders, including age, sex, race and ethnicity (Asian, Black, Hispanic, or White), obesity, type of insurance, geographical location, and physical and mental health comorbidities.

RESULTS

A total of 38 408 opioid-naive individuals (21 336 women [55.6%]; mean [SD] age, 66.2 [9.2] years) and 28 914 opioid-experienced individuals (18 426 women [63.7%]; mean [SD] age, 64.4 [9.3] years) were included. Receipt of any PT before TKR was associated with lower odds of long-term opioid use in the opioid-naive (adjusted odds ratio [aOR], 0.75 [95% CI, 0.60-0.95]) and opioid-experienced (aOR, 0.75 [95% CI, 0.70-0.80]) cohorts. Receipt of any post-TKR PT was associated with lower odds of long-term use of opioids in the opioid-experienced cohort (aOR, 0.75 [95% CI, 0.70-0.79]). Compared with 1 to 5 sessions of PT after TKR, 6 to 12 sessions (aOR, 0.82 [95% CI, 0.75-0.90]) and 13 or more sessions (aOR, 0.71 [95% CI, 0.65-0.77) were associated with lower odds in the opioid-experienced cohort. Compared with initiation of PT within 30 days after TKR, initiation 31 to 60 days or 61 to 90 days after TKR were associated with greater odds in the opioid-naive (31-60 days: aOR, 1.45 [95% CI, 1.19-1.77]; 61-90 days: aOR, 2.15 [95% CI, 1.43-3.22]) and opioid-experienced (31-60 days: aOR, 1.10 [95% CI, 1.02-1.18]; 61-90 days: aOR, 1.32 [95% CI, 1.12-1.55]) cohorts. Compared with passive PT, active PT was not associated with long-term opioid use in the opioid-naive (aOR, 1.00 [95% CI, 0.81-1.24]) or opioid-experienced (aOR, 0.99 [95% CI, 0.92-1.07]) cohorts.

CONCLUSIONS AND RELEVANCE

This cohort study suggests that receipt of PT intervention before and after TKR, receipt of 6 or more sessions of PT care after TKR, and initiation of PT care within 30 days after TKR were associated with lower odds of long-term opioid use. These findings suggest that PT may help reduce the risk of long-term opioid use after TKR.

OpiTrack: A Wearable-based Clinical Opioid Use Tracker with Temporal Convolutional Attention Networks

Opioid use disorder is a medical condition with major social and economic consequences. While ubiquitous physiological sensing technologies have been widely adopted and extensively used to monitor day-to-day activities and deliver targeted interventions to improve human health, the use of these technologies to detect drug use in natural environments has been largely underexplored. The long-term goal of our work is to develop a mobile technology system that can identify high-risk opioid-related events (i.e., development of tolerance in the setting of prescription opioid use, return-to-use events in the setting of opioid use disorder) and deploy just-in-time interventions to mitigate the risk of overdose morbidity and mortality. In the current paper, we take an initial step by asking a crucial question: Can opioid use be detected using physiological signals obtained from a wrist-mounted sensor? Thirty-six individuals who were admitted to the hospital for an acute painful condition and received opioid analgesics as part of their clinical care were enrolled. Subjects wore a noninvasive wrist sensor during this time (1-14 days) that continuously measured physiological signals (heart rate, skin temperature, accelerometry, electrodermal activity, and interbeat interval). We collected a total of 2070 hours (≈ 86 days) of physiological data and observed a total of 339 opioid administrations. Our results are encouraging and show that using a Channel-Temporal Attention TCN (CTA-TCN) model, we can detect an opioid administration in a time-window with an F1-score of 0.80, a specificity of 0.77, sensitivity of 0.80, and an AUC of 0.77. We also predict the exact moment of administration in this time-window with a normalized mean absolute error of 8.6% and R ² coefficient of 0.85.

Decreased Analgesic Requirements in Super Morbidly Versus Morbidly Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy

Background

Scarce data exists about analgesic requirements in super morbidly obese (SMO) patients who underwent sleeve gastrectomy. We attempted to investigate analgesic requirements for SMO, when compared with morbidly obese (MO) individuals who underwent sleeve gastrectomy and its impact on postoperative outcome.

Methods

We studied 279 consecutive patients (183 MO, 96 SMO) who underwent bariatric surgery. Data analysis included perioperative anaesthetic management, analgesic consumptions, opioids side effects, and ICU admission.

Results

The SMO group showed higher patients with asthma, epilepsy, obstructive sleep apnoea (OSA), and ASA III percentages (P = 0.014, P = 0.016, P ˂ 0.001, and P ˂ 0.001, respectively). There were no significant differences in the total morphine consumption intraoperatively, or after 24 h. However, reduced consumption of intraoperative fentanyl and morphine in SMO when calculated per total body weight (TBW) (P = 0.004 and P = 0.001, respectively). At PACU, tramadol consumption per TBW and lean body mass (LBM) were significantly reduced in SMO (P = 0.001 and P = 0.025, respectively). Paracetamol consumption was significantly reduced in the SMO group (P = 0.04). They showed higher comorbidities (P ˂ 0.001), longer anaesthesia time (P = 0.033), and greater ICU admissions (P ˂ 0.001). Vomiting was higher in the MO group (P = 0.004). Both groups showed comparable pain scores (P = 0.558) and PACU stay time (P = 0.060).

Conclusions

Super morbidly obese patients required fewer opioids and analgesics perioperatively. They exhibited higher comorbidities with greater anaesthesia time and ICU admissions. PACU stay time and pain scores were comparable.

Association between higher BMI and postoperative pain and opioid consumption in pediatric inpatients - A retrospective cohort study

BACKGROUND

Childhood and adolescent obesity increased in recent decades, and caregivers face an increasing number of obese pediatric surgical patients. Some clinical and pharmacogenetic data suggest that obese patients have altered pain sensitivity and analgesic requirements.

OBJECTIVE

To test the primary hypothesis that increased BMI in pediatric patients is associated with increased pain during the initial 48 postoperative hours. Secondarily, we tested whether BMI is associated with increased opioid consumption during the same period.

DESIGN

Retrospective single-center cohort study.

SETTING

Pediatric surgical wards in a tertiary medical center.

PATIENTS

A total of 808 opioid naïve patients aged 8 to 18 years having elective non-cardiac surgery with hospital stay of at least 48 h in the Cleveland Clinic between 2010 and 2015.

INTERVENTIONS

None.

MEASUREMENTS

Using U.S. Centers for Disease Control definitions for childhood weight classifications, we retrospectively evaluated the association between body mass index (BMI) percentile and time-weighted average pain scores and opioid consumption. We used multivariable linear regression to test for an association with postoperative pain scores, and multivariable gamma regression to test for an association with postoperative opioid consumption (in mg morphine equivalents Kg^-1).

RESULTS

BMI was not associated with postoperative pain after general, orthopedic, or neuro-spinal surgeries. Pain increased by 0.07 [98.75% CI: (0.01, 0.13), P_adj < 0.05] points per 5 percentile increase in BMI after neuro-cranial surgery. Higher BMI was associated with a decrease in postoperative opioid consumption (mean change [95% CI] -2.12% [-3.12%, -1.10%] in morphine equivalents Kg^-1 per 5 percentile increase in BMI, P < 0.001).

CONCLUSION

We found no clinically important increase in pain scores or opioid consumption in association with higher BMI in patients 8 to 18 years of age recovering from elective non-cardiac surgery.

Implications of a Retrospective Study on Weight-Based Risk for Post-Tonsillectomy Pain in Children

PURPOSE

The purpose was to examine if children experience weight-based risks for post-tonsillectomy pain (PTP) in the postanesthesia care unit (PACU).

DESIGN

This retrospective correlational cohort design included a sample of 180 children between the ages of 4 to 12 years who had tonsillectomy and adenoidectomy or tonsillectomy before August 2016; half were obese (OB) or overweight (OW).

METHODS

The sample was obtained from children who had surgery at a large pediatric hospital with an attached outpatient surgical center in North Texas. Children were defined as either OB and OW or non-OB and non-OW based on a cutoff of standardized body mass index z scores of 85th percentile and greater per the National Center for Health Statistics. Pain scores were obtained in the PACU after surgery. Early PTP was defined as the most severe pain experienced by a child in the first 15 minutes after extubation. Prolonged PTP was sustained and uncontrolled pain in the PACU.

FINDINGS

OB and OW status did not increase the likelihood of experiencing early PTP when examined by multiple logistic regression controlling for covariates (adjusted odds ratio, 1.391; P = .369). OB and OW status was associated with longer episodes of prolonged PTP (r_s[178] = 0.16; P = .03). OB and OW children were more likely to experience prolonged PTP in the PACU (χ²[1] = 8.353; P = .004), with these children experiencing an average PTP period twice as long as their peers.

CONCLUSIONS

OB and OW children did experience risk for prolonged PTP, averaging sustained pain for approximately twice as long as other children. The increased risk for prolonged PTP in OB and OW children occurred despite well-managed early PTP with rates that matched those of their peers. No weight-based risk for early PTP was observed. Further research is needed in the area of PTP management in OB and OW children.

Pooled Dosing and Efficacy Analysis of the Sufentanil Sublingual Tablet 30 mcg Across Demographic Subgroups for the Management of Moderate-to-Severe Acute Pain

PURPOSE

To aid nurses in dosing sufentanil sublingual tablet (SST) 30 mcg administered via a single-dose applicator, dosing requirements and efficacy of SST 30 mcg were analyzed across age, sex, race, and body mass index subgroups.

DESIGN

Patient characteristics were pooled from three postoperative studies (two placebo-controlled and one open-label) and one open-label emergency department study. Drug dosing and efficacy data were pooled from the postoperative studies.

METHODS

Efficacy was assessed through summed pain intensity difference to baseline during 12 hours across subgroups.

FINDINGS

Mean (standard deviation) drug doses administered from 0 to 12 hours was 3.9 (2.0) for SST 30 mcg and was less frequent for older (≥65 years) versus younger patients. The summed pain intensity difference to baseline during 12 hours was superior with SST 30 mcg versus placebo across all subgroups.

CONCLUSIONS

SST 30 mcg is a sublingual opioid analgesic with efficacy across demographic subgroups.

The impact of obesity and smoking on young individuals suffering from lumbar disc herniation: a retrospective analysis of 97 cases

The negative impact on spinal diseases may apply not only to obesity but also to smoking. To investigate the influence of obesity and smoking on the development and recovery of lumbar disc herniation in young adults. Retrospective analysis of 97 patients who presented with lumbar disc herniation at the authors' department between 2010 and 2017. Data were collected using the patients' digital health records including demographics, clinical and neurological characteristics, treatment details, and outcomes. Ninety-seven patients between 17 and 25 years were included in this retrospective analysis. Patients were categorized into two groups according to their body mass index: obese (O, ≥ 30 kg/m²) and non-obese (NO, < 30 kg/m²). The proportion of obese patients in our cohort vs. in the overall population differed significantly (19.4% vs. 3.8-7.1%, RR 3.17; p < 0.01). Group NO showed a trend toward faster recovery of motor deficits (p = 0.067) and pain (p = 0.074). Also, the proportion of regular smokers differed significantly from the numbers of known smokers of the same age (62.4% vs. 30.2%, RR 2.0; p = 0.01). Obesity plus smoking showed a significantly negative impact on motor deficits postoperatively (p = 0.015) and at discharge (p = 0.025), as well as on pain values (p = 0.037) and on analgesic consumption (p = 0.034) at 6 weeks follow-up. The negative impact of obesity and smoking on the occurrence of lumbar disc herniation could be demonstrated for individuals aged 25 or younger. Furthermore, a trend to earlier recovery of motor deficits and significantly lower pain scales for non-obese and non-smoking patients could be shown.

Framework to Explain the Progression of Pain in Obese or Overweight Children Undergoing Tonsillectomy

An estimated 100,000 obese (OB) and overweight (OW) children undergo tonsillectomy each year in the United States. Pain management in this population is particularly challenging because of weight-based dosing, clinician fears, potential for airway obstruction, and genetic differences. A framework is proposed to explain factors involved in the post-tonsillectomy pain (PTP) experience in OB and OW children. The tonsillectomy, the body's inflammatory state, and mechanical stressors comprise influencing factors in PTP progression. Clinician-delivered medication doses, genetic variants of drug metabolism, and soothing factors serve as mediating factors in the progression of PTP. Postanesthesia care unit (PACU) nurses may use this framework to better understand PTP progression in OB and OW children. PACU nurses may manipulate certain mediating factors discussed in this framework to moderate PTP progression in OB and OW children. Researchers may use this framework to support future research to improve PTP management in OB and OW children.

Drug- and alcohol-related mortality risk after bariatric surgery: evidence from a 7-year prospective multicenter cohort study

BACKGROUND

It is unclear whether bariatric surgery affects the risk of drug- and alcohol-related mortality.

OBJECTIVES

To compare the observed drug- and alcohol-related mortality rate with age, sex, race, and year-adjusted rates from the general U.S.

POPULATION

SETTING

The Longitudinal Assessment of Bariatric Surgery-2, a prospective cohort study of 2458 adults who underwent bariatric surgery at 10 U.S. hospitals between April 2006 and April 2009.

METHODS

Participants attended presurgery and annual postsurgery assessments for up to 7 years. Drug- and alcohol-related standardized mortality ratios (SMR) comparing the observed post-bariatric surgery mortality rate with the age, sex, race, and year-adjusted expected mortality rate from the general U.S. population, among the entire cohort, and among those who underwent Roux-en-Y gastric bypass (RYGB).

RESULTS

Ten deaths related to drug or alcohol use (6 accidental overdose, 1 intentional overdose, 1 intent unknown overdose, and 2 alcoholic liver disease) occurred across 15,616 person-years of follow-up, all among participants who underwent RYGB (n = 1770). The observed mortality rate was significantly higher than expected for all drug- and alcohol-related causes overall (SMR = 2.10, 95% confidence interval = 1.01-3.86, P = .03) and among participants who underwent RYGB (SMR = 2.90, 95% confidence interval = 1.39-5.33, P = .003). The RYGB SMRs were significant for all overdoses (P = .002) and accidental overdoses (P = .01) and in the same direction but nonsignificant for intentional overdoses, intent unknown overdoses, and alcoholic liver disease (P for all ≥. 05).

CONCLUSIONS

Drug- and alcohol-related mortality is significantly higher than expected in the 7 years after bariatric surgery, specifically after RYGB.

Provider preferences for postoperative analgesia in obese and non-obese patients undergoing ambulatory surgery

Background

Few guidelines exist on safe prescription of postoperative analgesia to obese patients undergoing ambulatory surgery. This study examines the preferences of providers in the standard treatment of postoperative pain in the ambulatory setting.

Methods

Providers from five academic medical centers within a single US city were surveyed from May–September 2015. They were asked to provide their preferred postoperative analgesic routine based upon the predicted severity of pain for obese and non-obese patients. McNemar’s tests for paired observations were performed to compare prescribing preferences for obese vs. non-obese patients. Fisher’s exact tests were performed to compare preferences based on experience: > 15 years vs. ≤15 years in practice, and attending vs. resident physicians.

Results

A total of 452 providers responded out of a possible 695. For mild pain, 119 (26.4%) respondents prefer an opioid for obese patients vs. 140 (31.1%) for non-obese (p = 0.002); for moderate pain, 329 (72.7%) for obese patients vs. 348 (77.0%) for non-obese (p = 0.011); for severe pain, 398 (88.1%) for obese patients vs. 423 (93.6%) for non-obese (p < 0.001). Less experienced physicians are more likely to prefer an opioid for obese patients with moderate pain: 70 (62.0%) attending physicians with > 15 years in practice vs. 86 (74.5%) with ≤15 years (p = 0.047), and 177 (68.0%) attending physicians vs. 129 (83.0%) residents (p = 0.002).

Conclusions

While there is a trend to prescribe less opioid analgesics to obese patients undergoing ambulatory surgery, these medications may still be over-prescribed. Less experienced physicians reported prescribing opioids to obese patients more frequently than more experienced physicians.

Use of prescribed opioids before and after bariatric surgery: prospective evidence from a U.S. multicenter cohort study

BACKGROUND

Limited evidence suggests bariatric surgery may not reduce opioid analgesic use, despite improvements in pain.

OBJECTIVE

To determine if use of prescribed opioid analgesics changes in the short and long term after bariatric surgery and to identify factors associated with continued and postsurgery initiated use.

SETTING

Ten U.S. hospitals.

METHODS

The Longitudinal Assessment of Bariatric Surgery-2 is an observational cohort study. Assessments were conducted presurgery, 6 months postsurgery, and annually postsurgery for up to 7 years until January 2015. Opioid use was defined as self-reported daily, weekly, or "as needed" use of a prescribed medication classified as an opioid analgesic.

RESULTS

Of 2258 participants with baseline data, 2218 completed follow-up assessment(s) (78.7% were female, median body mass index: 46; 70.6% underwent Roux-en-Y gastric bypass). Prevalence of opioid use decreased after surgery from 14.7% (95% CI: 13.3-16.2) at baseline to 12.9% (95% CI: 11.5-14.4) at month 6 but then increased to 20.3%, above baseline levels, as time progressed (95% CI: 18.2-22.5) at year 7. Among participants without baseline opioid use (n = 1892), opioid use prevalence increased from 5.8% (95% CI: 4.7-6.9) at month 6 to 14.2% (95% CI: 12.2-16.3) at year 7. Public versus private health insurance, more pain presurgery, undergoing subsequent surgeries, worsening or less improvement in pain, and starting or continuing nonopioid analgesics postsurgery were significantly associated with higher risk of postsurgery initiated opioid use.

CONCLUSION

After bariatric surgery, prevalence of prescribed opioid analgesic use initially decreased but then increased to surpass baseline prevalence, suggesting the need for alternative methods of pain management in this population.

Obesity and chronic pain: systematic review of prevalence and implications for pain practice

The combination of obesity and pain may worsen a patient's functional status and quality of life more than each condition in isolation. We systematically searched PubMed/MEDLINE and the Cochrane databases for all reports published on obesity and pain. The prevalence of combined obesity and pain was substantial. Good evidence shows that weight reduction can alleviate pain and diminish pain-related functional impairment. However, inadequate pain control can be a barrier to effective lifestyle modification and rehabilitation. This article examines specific pain management approaches for obese patients and reviews novel interventional techniques for treatment of obesity. The infrastructure for simultaneous treatment of obesity and pain already exists in pain medicine (eg, patient education, behavioral medicine approaches, physical rehabilitation, medications, and interventional treatment). Screening for obesity, pain-related disability, and behavioral disorders as well as monitoring of functional performance should become routine in pain medicine practices. Such an approach requires additional physician and staff training. Further research should focus on better understanding the interplay between these 2 very common conditions and the development of effective treatment strategies.

Acute pain Factors predictive of post-operative pain and opioid requirement in multimodal analgesia following knee replacement

BACKGROUND

Despite the development of multimodal analgesia for postoperative pain management, opioids are still required for effective pain relief after knee arthroplasty. We aimed to identify the determinants of post-operative pain intensity and post-operative opioid requirement in this context.

METHODS

In this observational prospective study, we recorded patient characteristics, pre-operative pain intensity, anxiety and depression levels, sensitivity and pain thresholds in response to an electrical stimulus, and mu-opioid receptor (OPRM1) and catechol-O-methyltransferase (COMT) single-nucleotide polymorphisms. Multivariate linear regression models were used to identify predictors of post-operative pain at rest and opioid requirement.

RESULTS

We included 109 patients. Pre-operative pain at rest (p = 0.047), anxiety level (p = 0.001) and neuropathic pain symptoms (p = 0.030) were independently and positively associated with mean post-operative pain intensity adjusted for mean post-operative morphine equivalent dose (MED). Mean post-operative pain intensity at rest was lower (p = 0.006) in patients receiving celecoxib and pregabalin in the post-operative period, with all other variables constant. Mean post-operative MED over 5 days was low, but highly variable (78.2 ± 32.1 mg, from 9.9 to 170 mg). Following adjustment for mean post-operative pain intensity, it was independently negatively correlated with age (p = 0.004), and positively correlated with associated paracetamol treatment (p = 0.031). No genetic effect was detected in our sample.

CONCLUSIONS

Our findings suggest that clinicians could use the pre-operative pain profile, in terms of anxiety levels, neuropathic pain symptoms, and chronic pre-operative pain intensity, to improve the efficacy of pain management after knee surgery.

Perioperative management of bariatric surgery patients

PURPOSE

The perioperative management of bariatric surgery patients is described.

SUMMARY

Obesity and anatomical changes create unique challenges for clinicians when caring for bariatric surgery patients. Common bariatric surgery procedures performed include Roux-en-Y gastric bypass, sleeve gastrectomy, and adjustable gastric banding. Pain management in the acute postoperative period depends on careful dosing of opioid agents and the use of adjunctive agents. Prevention and management of infectious complications include appropriate surgical prophylaxis, monitoring and rapid treatment of suspected intra-abdominal infections, and detection and treatment of Helicobacter pylori infection. Venous thromboembolism (VTE) prophylaxis and treatment are complicated by obesity, and the use of pharmacologic agents must be balanced with bleeding risk. Bleeding is a serious complication that should be closely monitored in the immediate postoperative period. Blood products remain first-line therapy for the treatment of bleeding in this population. Acute differences in drug absorption as well as emerging hormonal changes necessitate the immediate postoperative adjustment of chronic medications to ensure both safety and efficacy. Pharmacists are valuable members of interprofessional teams for bariatric surgery patients because they provide expertise on the availability of dosage forms and dosage modification to ensure that patient pharmacotherapy is not interrupted; assist in the management of hypertension, diabetes, and psychotropic medications; and ensure appropriate antimicrobial prophylaxis and VTE prophylaxis and treatment dosages.

CONCLUSION

The management of patients in the perioperative period of bariatric surgery requires appropriate selection and dosing of medications for pain management and treatment of infectious complications, VTE, bleeding, and other chronic diseases.

The future of genomic testing in primary care: the changing face of personalized medicine

Primary care is recognized worldwide as a key component for improving health outcomes in the population. At the same time, healthcare systems are rapidly changing with increasing expectations from technological advances. Genomics is a major driver in changing how medicine is being practiced; however, the importance for primary care has been under-appreciated. Strategically implementing genomics in a way that accounts for the unique characteristics of the primary care context is essential. In this perspective, we present important areas that we believe are critical in consideration of both the future of genomic medicine and primary healthcare delivery.

Transversus abdominis plane infiltration for laparoscopic gastric banding: A pilot study

AIM: To estimate an effect size for the transversus abdominis plane (TAP) infiltration on quality of recovery in patients undergoing laparoscopic gastric band surgery.

METHODS: The pilot study was a randomized, double blinded, placebo controlled trial. Patients undergoing laparoscopic gastric band surgery were randomized to receive a bilateral TAP infiltration with 20 mL of 0.5% ropivacaine or saline. The evaluated outcomes included quality of recovery-40 (QoR-40) at 24 h, postoperative opioid consumption and pain. Data was examined using the Mann-Whitney U test.

RESULTS: Nineteen subjects were recruited. There was a positive trend favoring the TAP infiltration group in global QoR-40 scores at 24 h after surgery, median [interquartile range (IQR)] of 175.5 (170-189) compared to 170 (160-175) in the control group (P = 0.06). There also a positive trend toward a lower cumulative opioid consumption in the TAP infiltration group, median (IQR) of 7.5 (2.5-11.5) mg iv morphine equivalents compared to 13 (7-21.5) in the control group (P = 0.07). Correlation analysis (Spearman’s Rho) demonstrated an inverse relationship between 24 h cumulative opioid consumption and global QoR-40 scores, -0.49 (P = 0.03).

CONCLUSION: The use of multimodal analgesic techniques to reduce opioid related side effects is particularly desirable in morbidly obese patients undergoing gastric reduction surgery. The TAP infiltration seems to have a clinically important effect in reducing postoperative opioid consumption and improve quality of recovery after laparoscopic gastric band surgery in morbid obese patients. Future studies to confirm the beneficial effects of the TAP infiltration in these patients are warranted.