Safety and efficacy of patient-controlled analgesia

Subcutaneous Patient-Controlled Analgesia in Home-Based Palliative Care: "It's as Straightforward as Pushing a Button, Right at my Fingertips"

Subcutaneous patient-controlled analgesia (SCPCA) in home-based palliative care is a potentially valuable option for providing effective pain relief to some patients, particularly when conventional analgesic approaches prove ineffective or are refused. Our case report illustrates the use of SPCA for the management of breakthrough pain in a patient receiving palliative care at home with no improvement after multiple previous treatments. SCPCA was found to be safe and successful. Future research is essential to explore its precise role, appropriate indications, prescription guidelines, and safety considerations across various palliative care contexts.

Reduced side effects and improved pain management by continuous ketorolac infusion with patient-controlled fentanyl injection compared with single fentanyl administration in pelviscopic gynecologic surgery: a randomized, double-blind, controlled study

BACKGROUND

A combination of opioids and adjunctive drugs can be used for intravenous patient-controlled analgesia (PCA) to minimize opioid-related side effects. We investigated whether two different analgesics administered separately via a dual-chamber PCA have fewer side effects with adequate analgesia than a single fentanyl PCA in gynecologic pelviscopic surgery.

METHODS

This prospective, double-blind, randomized, and controlled study included 68 patients who underwent pelviscopic gynecological surgery. Patients were allocated to either the dual (ketorolac and fentanyl delivered by a dual-chamber PCA) or the single (fentanyl alone) group. Postoperative nausea and vomiting (PONV) and analgesic quality were compared between the two groups at 2, 6, 12, and 24 h postoperatively.

RESULTS

The dual group showed a significantly lower incidence of PONV during postoperative 2-6 h (P = 0.011) and 6-12 h (P = 0.009). Finally, only two patients (5.7%) in the dual group and 18 (54.5%) in the single group experienced PONV during the entire postoperative 24 h and could not maintain intravenous PCA (odds ratio: 0.056, 95% CI [0.007, 0.229], P < 0.001). Despite the administration of less fentanyl via intravenous PCA during the postoperative 24 h in the dual group than in the single group (66.0 ± 77.8 vs. 383.6 ± 70.1 μg, P < 0.001), postoperative pain had no significant intergroup difference.

CONCLUSIONS

Two different analgesics, continuous ketorolac and intermittent fentanyl bolus, administered via dual-chamber intravenous PCA, showed fewer side effects with adequate analgesia than conventional intravenous fentanyl PCA in gynecologic patients undergoing pelviscopic surgery.

Optimal Post-Operative Nalbuphine Dose Regimen: A Randomized Controlled Trial in Patients with Laparoscopic Cholecystectomy

Background and Objectives: Optimal opioid analgesia is an excellent analgesia that does not present unexpected adverse effects. Nalbuphine, acting on the opioid receptor as a partial mu antagonist and kappa agonist, is considered a suitable option for patients undergoing laparoscopic surgery. Therefore, we aim to investigate the appropriate dosage of nalbuphine for post-operative pain management in patients with laparoscopic cholecystectomy. Materials and Methods: Patients were randomly categorized into low, medium, and high nalbuphine groups. In each group, a patient control device for post-operative pain control was programed with a low (0.05 mg/kg), medium (0.10 mg/kg), or high (0.20 mg/kg) nalbuphine dose as a loading dose and each bolus dose with a lockout interval of 7 min and without background infusion. Primary and secondary outcomes included the post-operative pain scale and nalbuphine consumption, and episodes of post-operative opioid-related adverse events and satisfactory scores. Results: The low-dosage group presented a higher initial self-reported pain score in comparison to the other two groups for the two hours post-op (p = 0.039) but presented lower nalbuphine consumption than the other two groups for four hours post-op (p = 0.047). There was no significant difference in the analysis of the satisfactory score and adverse events. Conclusions: An appropriate administration of nalbuphine could be 0.1 to 0.2 mg/kg at the initial four hours; this formula could be modified to a lower dosage (0.05 mg/kg) in the post-operative management of laparoscopic cholecystectomy.

Does intravenous patient-controlled analgesia or continuous block prevent rebound pain following infraclavicular brachial plexus block after distal radius fracture fixation? A prospective randomized controlled trial

BACKGROUND

The purpose of this study was to investigate the role of opioid-based intravenous patient-controlled analgesia (IV PCA) or continuous brachial plexus block (BPB) in controlling rebound pain after distal radius fracture (DRF) fixation under BPB as well as total opioid consumption.

METHODS

A total of 66 patients undergoing surgical treatment for a displaced DRF with volar plate fixation were randomized to receive a single infraclavicular BPB (BPB only group) (n = 22), a single infraclavicular BPB with IV PCA (IV PCA group) (n = 22), or a single infraclavicular BPB with continuous infraclavicular BPB (continuous block group) (n = 22). The visual analog scale (VAS) for pain and the amount of pain medication were recorded at 4, 6, 9, 12, 24, and 48 h and two weeks postoperatively.

RESULTS

At postoperative 9 h, the pain VAS score was significantly higher in the BPB only group (median: 2; Q1, Q3 [1, 3]) than in the IV PCA (0 [0, 1.8], P = 0.006) and continuous block groups (0 [0, 0.5], P = 0.009). At postoperative 12 h, the pain VAS score was significantly higher in the BPB only group (3 [3, 4]) than in the continuous block group (0.5 [0, 3], P = 0.004). The total opioid equivalent consumption (OEC) was significantly higher in the IV PCA group (350.3 [282.1, 461.3]) than in the BPB only group (37.5 [22.5, 75], P < 0.001) and continuous block group (30 [15, 75], P < 0.001); however, OEC was not significantly different between the BPB only group and the continuous block group (P = 0.595).

CONCLUSIONS

Although continuous infraclavicular BPB did not reduce total opioid consumption compared to BPB only, this method is effective for controlling rebound pain at postoperative 9 and 12 h following DRF fixation under BPB.

The effect of newly designed dual-channel elastomeric pump for intravenous patient-controlled analgesia after total laparoscopic hysterectomy: a randomized, double-blind, prospective study

BACKGROUND

A newly designed intravenous patient-controlled analgesia (PCA) device with a dual-channel elastomeric infusion pump has been recently introduced. One channel is a continuous line with a constant flow rate basal infusion, while the other channel has an adjustable flow rate and bolus function and is labeled as a selector-bolus channel. This study compared dual and single-channel intravenous PCA in terms of clinical effect and quality of recovery.

METHODS

Eighty-four patients undergoing total laparoscopic hysterectomy were randomly allocated to a 1-channel group (n = 41) or a 2-channel group (n = 43). Only the selector-bolus channel was utilized, but the continuous channel was not utilized in the 1-channel group, but both channels were utilized in the 2-channel group. In the 1-channel group, 16 μg/kg of fentanyl, 2 mg/kg of ketorolac, and 12 mg of ondansetron with normal saline were administered to the selector-bolus channel and normal saline only in the continuous channel for blinding. In the 2-channel group, 16 μg/kg of fentanyl was administered to the selector-bolus channel, and ketorolac (2 mg/kg) and ondansetron (12 mg) were administered via the continuous channel. The quality of recovery was evaluated preoperatively and 24 h postoperatively using the Quality of Recovery-40 (QoR-40). Cumulative PCA consumption, postoperative pain rated using the numeric rating scale (NRS; during rest/cough), and postoperative nausea were evaluated 6, 12, 24, 36, and 48 h after surgery. Incidence of vomiting and use of antiemetics and rescue analgesics was measured.

RESULTS

The 24-h postoperative QoR-40 score was higher in the 2-channel group than in the 1-channel group (P=0.031). The incidence of nausea at 12 h and 36 h was significantly higher in the 1-channel group (P=0.043 and 0.040, respectively), and antiemetic use was more frequent in the 1-channel group (P=0.049). Patient satisfaction was higher in the 2-channel group (P=0.036). No significant differences were observed in pain scores during resting/cough or cumulative PCA consumption.

CONCLUSIONS

The 2-channel PCA showed better patient satisfaction with higher QoR-40 during the recovery compared with the 1-channel PCA. Better satisfaction was associated with lower nausea and reduced rescue antiemetics by maintaining the infusion of adjuvant analgesic agents and antiemetic agents constantly by utilizing dual channels.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov , NCT04082039 on 9 September 2019.

Group-based trajectory analysis of acute pain after spine surgery and risk factors for rebound pain

Background

This retrospective study was designed to explore the types of postoperative pain trajectories and their associated factors after spine surgery.

Materials and methods

This study was conducted in a single medical center, and patients undergoing spine surgery with intravenous patient-controlled analgesia (IVPCA) for postoperative pain control between 2016 and 2018 were included in the analysis. Maximal pain scores were recorded daily in the first postoperative week, and group-based trajectory analysis was used to classify the variations in pain intensity over time and investigate predictors of rebound pain after the end of IVPCA. The relationships between the postoperative pain trajectories and the amount of morphine consumption or length of hospital stay (LOS) after surgery were also evaluated.

Results

A total of 3761 pain scores among 547 patients were included in the analyses and two major patterns of postoperative pain trajectories were identified: Group 1 with mild pain trajectory (87.39%) and Group 2 with rebound pain trajectory (12.61%). The identified risk factors of the rebound pain trajectory were age less than 65 years (odds ratio [OR]: 1.89; 95% CI: 1.12–3.20), female sex (OR: 2.28; 95% CI: 1.24–4.19), and moderate to severe pain noted immediately after surgery (OR: 3.44; 95% CI: 1.65–7.15). Group 2 also tended to have more morphine consumption (p < 0.001) and a longer length of hospital stay (p < 0.001) than Group 1.

Conclusion

The group-based trajectory analysis of postoperative pain provides insight into the patterns of pain resolution and helps to identify unusual courses. More aggressive pain management should be considered in patients with a higher risk for rebound pain after the end of IVPCA for spine surgery.

Nucleus Tractus Solitarius Neurons Activated by Hypercapnia and Hypoxia Lack Mu Opioid Receptor Expression

Impaired chemoreflex responses are a central feature of opioid-induced respiratory depression, however, the mechanism through which mu opioid receptor agonists lead to diminished chemoreflexes is not fully understood. One brainstem structure involved in opioid-induced impairment of chemoreflexes is the nucleus of the solitary tract (NTS), which contains a population of neurons that express mu opioid receptors. Here, we tested whether caudal NTS neurons activated during the chemoreflex challenge express mu opioid receptors and overlap with neurons activated by opioids. Using genetic labeling of mu opioid receptor-expressing neurons and cFos immunohistochemistry as a proxy for neuronal activation, we examined the distribution of activated NTS neurons following hypercapnia, hypoxia, and morphine administration. The main finding was that hypoxia and hypercapnia primarily activated NTS neurons that did not express mu opioid receptors. Furthermore, concurrent administration of morphine with hypercapnia induced cFos expression in non-overlapping populations of neurons. Together these results suggest an indirect effect of opioids within the NTS, which could be mediated through mu opioid receptors on afferents and/or inhibitory interneurons.

The usefulness of dual channel elastomeric pump for intravenous patient-controlled analgesia in geriatrics: a randomized, double-blind, prospective study

BACKGROUND

Intravenous patient-controlled analgesia (IV-PCA) is often used in the postoperative period. However, determining an appropriate opioid dose is difficult. A previous study suggested the usefulness of variable-rate feedback infusion. In this study, we used a dual-channel elastomeric infusion pump to provide changes in PCA infusion rate by pain feedback.

METHODS

Ninety patients undergoing orthopedic surgery of American Society of Anesthesiologists grade I-III and 65 to 79 years of age participated in the study. All patients were given a dual-chamber PCA. Patients were randomly allocated to a treatment group (Group D; PCA drugs divided into both chambers) or control group (Group C; PCA drugs only in the constant flow chamber with normal saline in the adjustable flow chamber). The primary outcome was the amount of fentanyl consumption via PCA bolus. The secondary outcome variables were pain score, total fentanyl consumption, rescue analgesic use, patient satisfaction, recovery scores, and adverse events including postoperative nausea and vomiting (PONV).

RESULTS

Group D showed decreased fentanyl consumption of the PCA bolus, a decrease in rescue analgesic use, and better patient satisfaction compared with group C. The incidence of PONV was much higher in group C. There was no difference in other adverse events.

CONCLUSIONS

We showed the usefulness of dual chamber IV-PCA to change the flow rate related to pain feedback without any complications. Our results suggest a noble system that might improve existing IV-PCA equipment.

TRIAL REGISTRATION

The study registered at UMIN clinical trial registry (registered date: 05/03/2020, registration number: UMIN000039702 ).

Effectiveness of Patient-Controlled Intravenous Analgesia (PCIA) with Sufentanil Background Infusion for Post-Cesarean Analgesia: A Randomized Controlled Trial

Purpose

To investigate the effectiveness of sufentanil patient-controlled intravenous analgesia pump (PCIA) and background infusion in patients of post-cesarean analgesia.

Patients and Methods

This trial compared two groups of women undergoing cesarean section and receiving PCIA: no background infusion group (n=30), 6-min lockout time, and background infusion group (n=30), 2 mL/h infusion, 10-min lockout time. Both groups with 2 μg/kg sufentanil was diluted to 100 mL with normal saline. VAS scores at rest at 36 h was the primary endpoint. The secondary endpoints were the VAS scores at rest at 6, 12, and 24 h, the total amount of sufentanil consumed, the Ramsay sedation score (RSS) assessed at the same time points, postpartum bleeding within 24 h, the injection/attempt (I/A) ratio, BP and HR, PONV, side effects of sufentanil.

Results

Compared with the no background infusion group, the background infusion group showed lower VAS pain scores at 6, 12, and 24 h (P<0.01), but no differences at 36 h (95% CI = -0.5-0.8. P>0.05). Attempts, injections, and total sufentanil consumption were significantly different between the two groups (P<0.001), but without difference in I/A. Bleeding was less in the background infusion group at 1 h (P=0.03). The minimal respiration rates were not significantly different between groups.

Conclusion

Background infusion increased the total consumption of sufentanil within 36 h after cesarean section. Although it did not reduce uterine contraction pain and wound pain at 36 h, it significantly reduced the pain at 6, 12, and 24 h after cesarean section. It improved patient satisfaction and reduced the amount of bleeding after 1 h. Importantly, it did not increase the incidence of hypertension, PONV and respiratory depression.

Multimodal Analgesia in the Era of the Opioid Epidemic

This article attempts to review the key components of a multimodal analgesic regimen for the treatment of acute pain. Adhering to these key components will help reduce the opioid burden to surgical patients while reducing acute pain. As well, this regimen is intended to reduce further negative contributions to the opioid crisis.

Patient controlled analgesia for the management of acute pain in the emergency department: A systematic review

BACKGROUND

The most common presenting complaint to the emergency department (ED) is pain. Several studies have shown that a large proportion of ED patients either receive no or sub-optimal analgesia. Patient-controlled analgesia (PCA) pumps used in the post-operative setting has shown to decrease total opioid consumption and has increased patient and nurse satisfaction.

OBJECTIVE

The purpose of this systematic review was to evaluate clinical trials that have used PCAs in the ED setting, to evaluate safety and efficacy as well as patient and healthcare provider experience.

METHODS

A search of PubMed, MEDLINE, and the Cochrane Database was conducted using the MESH search terms emergency department, patient-controlled analgesia, and acute pain up to September 2021. These terms were searched in all fields of publication and were limited to the English-language articles, clinical "human" studies, and studies that included the use of patient-controlled analgesia in the setting of the emergency department.

RESULTS

The search initially identified 227 potentially relevant articles and a total of 10 studies met criteria for inclusion. ED use of PCA therapy was associated with increased patient satisfaction, decreased pain scores, and an overall increase in opioid consumption.

CONCLUSION

The quality, the differences in study methods and outcome measures used, and heterogeneity of the studies performed to date do not provide adequate evidence to support its widespread use in the ED. Well-designed studies conducted in the ED are still needed to evaluate the ideal patient population to whom these PCAs may provide the most benefit as well as a robust cost-analysis to ensure feasibility of use in the future.

Survey of physician comfort and attitudes on perioperative opioid prescription in patients with chronic pain

Objective:

This study examines current practices, experiences, beliefs, concerns regarding negative outcomes and confidence of non-pain specialty anaesthetists regarding prescribing opioids to chronic pain patients.

Design:

An electronic cross-sectional survey was conducted by physicians from the Division of Anaesthesiology, excluding pain specialists, at the Singapore General Hospital.

Methods:

An online survey was conducted, investigating: (a) sociodemographic and practice characteristics; (b) current opioid prescribing practices; (c) experiences and beliefs towards prescribing opioid analgesics for chronic non-malignant pain; (d) confidence and comfort when prescribing opioids; and (e) educational and training needs in chronic pain management.

Results:

A total of 123 anaesthetists (80.9%) responded to the survey. It was noted that only 38.2% of respondents were comfortable managing patients with chronic pain. The majority (86.2%) felt that anaesthetists should be the primary doctors in the management of postoperative pain in chronic pain patients, and 61% believed that chronic pain trained specialist anaesthetists should be responsible; 92.7% of respondents agreed that patients who are educated about their pain tend to do better. Most importantly, 96.7% of respondents feel that they will benefit from more education regarding pain management in chronic pain patients.

Conclusions:

The majority of non-pain specialist anaesthetists recognise the importance of education regarding pain management for non-malignant chronic pain patients. Many feel that they are not confident in managing these patients and will benefit from continuing medical education and self-assessment courses to improve their confidence. These results could be used to enrich current pain management courses.

Short-term outcomes of laparoscopic versus open total gastrectomy after neoadjuvant chemotherapy: a cohort study using the propensity score matching method

Background

Until now, little is known about the benefit of laparoscopic total gastrectomy (LTG) after neoadjuvant chemotherapy (NACT). This study was designed to compare the safety and efficacy of the LTG versus the open total gastrectomy (OTG) approach after NACT treatment in patients with advanced gastric cancer (AGC).

Methods

This study involved a cohort of 145 patients with AGC who underwent total gastrectomy after NACT at our centre between April 2013 and August 2018 including 24 cases of LTG and 121 OTG. The baseline characteristics were matched based on 1:2 balanced propensity score-matching method.

Results

Sixty-nine marched cases were finally analysed (23 LTG vs. 46 OTG). All patients underwent R0 resection. Compared to the OTG group, the LTG group had a longer surgery duration (P<0.001), but a shorter incision length (P<0.001) and less intravenous patient-controlled analgesia (IV-PCA) time after surgery (P=0.027). No statistical differences were observed in terms of blood loss, retrieved lymph nodes (LNs), resection margin, length of stay, postoperative pain intensity, and complications (P>0.05).

Conclusions

LTG had comparable safety and histological findings to OTG after NACT in the perioperative period; however, LTG is less invasive and patients can benefit from less IV-PCA use. Further research is needed to investigate long-term effects.

Keywords

Gastric cancer (GC); neoadjuvant chemotherapy (NACT); safety; laparoscopic technique.

Ultrasound-Guided Quadratus Lumborum Block for Postoperative Pain in Abdominoplasty: A Randomized Controlled Study

BACKGROUND

Postoperative pain after abdominoplasty can delay postoperative ambulation, leading to life-threatening complications. Previous reports have shown the utility of quadratus lumborum block in providing adequate pain relief and avoiding side effects after numerous abdominal operations. The purpose of this randomized controlled trial was to demonstrate the efficacy of the quadratus lumborum block in abdominoplasty.

METHODS

Patients were randomly allocated to receive a bilateral quadratus lumborum block with either ropivacaine or normal saline. Postoperative cumulative analgesic medication consumption, pain severity at rest and on movement, and quality of recovery were evaluated and compared in both groups.

RESULTS

Twenty patients were allocated to each group. Total morphine dose received in the postanesthesia care unit was lower in the ropivacaine group than in the control group, with a mean of 3.4 mg and 6.6 mg, respectively. Cumulative tramadol consumption per patient in the first 48 hours postoperatively was significantly lower in the ropivacaine group compared with the control group (42.5 mg versus 190 mg; p = 0.0031). The Numeric Rating Scale both at rest and with effort was significantly lower in the ropivacaine group compared with the control group. The median quality of recovery for the ropivacaine group was 133 compared with 112 for the control group (p < 0.0001).

CONCLUSIONS

Quadratus lumborum block in abdominoplasty reduces postoperative pain and opioid consumption and improves the quality of recovery. Further studies are needed to compare the quadratus lumborum block to more traditional blocks.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Parental Assessment of Pain Control Following Pediatric Circumcision: Do Opioids Make a Difference?

OBJECTIVE

To determine whether a postoperative prescription for opioids affects parental assessment of pain control following pediatric circumcision.

METHODS

This postoperative survey assessed the parental assessment of pain control in 199 patients, ages<18 years undergoing circumcision. This study was conducted at a quaternary care children's hospital in Houston, Texas from December 2018 to January 2020. Postoperative pain regimens included acetaminophen and ibuprofen or combination hydrocodone/acetaminophen in addition to ibuprofen for postoperative analgesia based on the surgical preference. The primary study outcome was identification of the proportion of parents rating their child's analgesia following pediatric circumcision as poor or inadequate based on the postoperative analgesic regimen.

RESULTS

Of the 502 surveys sent, the response rate was 40% (199/502) of those who received the survey email, and 64% (199/308) for those who opened the email. Between the opioid and nonopioid groups, there was no difference in, race/ethnicity (Caucasian; 28% vs 37%; P = .43) or insurance status (insured; 51% vs 45%; P = .44). The proportion of parents who rated their child's pain as poor or inadequately controlled following circumcision was relatively rare:5.5% and 1.1% in the nonopioid and opioid groups, respectively. Parents rating their child's pain as excellent with regards to pain control following circumcision were 61% and 53% in the nonopioids and opioid groups, respectively.

CONCLUSION

The results of this study indicate that nonopioid analgesic regimens following pediatric circumcision were not associated with decreased parental satisfaction or an increasing assessment of poor or inadequately controlled pain. Limiting opioid exposure following pediatric circumcision is feasible and does not result in worse parental satisfaction with the analgesic plan.

Serratus anterior plane block versus intercostal nerve block for postoperative analgesic effect after video-assisted thoracoscopic lobectomy: A randomized prospective study

BACKGROUND

Serratus anterior plane block (SAPB) and intercostal nerve block (ICNB) are attractive options for multimodal analgesia in patients undergoing thoracoscopic surgery, but which block is superior remains unclear.

OBJECTIVE

The present study aimed to assess the effect of SAPB versus ICNB on reducing postoperative pain after video-assisted thoracoscopic surgery (VATS) for lobectomy.

METHODS

This prospective, randomized, active-intervention-controlled, subject-assessor-blinded, single-center, parallel-group trial allocated 18- to 80-year-old patients with American Society of Anesthesiologists status I to III to receive either SAPB or ICNB in a 1:1 ratio. The primary outcome was numerical pain rating scale (NRS) scores during the first 24 hours postoperatively. The secondary outcomes were postoperative cumulative doses of ketorolac and fentanyl, and the occurrence of postoperative adverse effects.

RESULTS

Among the 57 patients assessed for eligibility, 50 were randomly assigned in a 1:1 ratio. Due to conversion to open thoracotomy and patient-controlled analgesia pump failure, 4 patients were excluded and 46 were analyzed. The intergroup differences in NRS scores were not statistically significant at any time point. Cumulative consumptions of fentanyl and ketorolac were also not significantly different. No perioperative adverse events occurred. Postoperative complications were also absent, except for nausea (2/23 patients [8.7% in both groups]).

CONCLUSION

Results of the present study do not clarify whether SAPB or ICNB has a superior effect on reducing pain after VATS, thereby suggesting they may exert similar analgesic effects.

Early Postoperative Pain Predicts 2-Year Functional Outcomes following Knee Arthroplasty

Pain control following knee arthroplasty is extremely important to both patients and surgeons to improve the perioperative experience; however, the implication of early pain control on long-term outcomes following knee arthroplasty remains poorly understood. We hypothesized that poor early pain control results in poor functional outcomes 2 years following total (TKA) and unicondylar knee arthroplasty (UKA). This retrospective study reviewed 242 TKA and 162 UKA performed at a single institution by two surgeons. Mean visual analog scale (VAS) pain scores were collected for first 3 postoperative days. Patients were prospectively evaluated using short form (SF-12), the Western Ontario and McMaster University osteoarthritis index (WOMAC), and the Knee Society functional score (KSFS) questionnaires. Pearson's correlation coefficients were calculated between mean VAS pain scores and functional outcome scores at 2 years. In the TKA group, poorly controlled perioperative pain correlated with poorer functional scores at 2 years. There was a significant negative correlation between early mean VAS pain scores (mean, 3.2 ± 2.0) and most 2-year functional outcomes including SF-12 physical score (r = -0.227, p ≤ 0.01), WOMAC pain scores (r = -0.268, p ≤ 0.01), WOMAC stiffness scores (r = -0.224, p < 0.01), WOMAC function score (r = -0.290, p 0.01), and KSFS (r = -0.175, p = 0.031). Better control of early pain was associated with improved functional outcomes at 2 years following TKA. We also found significant negative correlations between preoperative functional scores and early postoperative pain scores. Collectively, using preoperative and early postoperative pain scores, we identified an "at-risk" patient group that manifested an inferior functional outcome at 2 years; these patients may benefit from closer surveillance and a multidisciplinary approach to pain and function to optimize their clinical outcome following knee arthroplasty.

Comparison of Postoperative Renal Function between Non-Steroidal Anti-Inflammatory Drug and Opioids for Patient-Controlled Analgesia after Laparoscopic Nephrectomy: A Retrospective Cohort Study

Non-steroidal anti-inflammatory drugs (NSAIDs) can be used as opioid alternatives for patient-controlled analgesia (PCA). However, their use after nephrectomy has raised concerns regarding possible nephrotoxicity. This study compared postoperative renal function and postoperative outcomes between patients using NSAID and patients using opioids for PCA in nephrectomy. In this retrospective observational study, records were reviewed for 913 patients who underwent laparoscopic or robot-assisted laparoscopic nephrectomy from 2015 to 2017. After propensity score matching, 247 patients per group were analyzed. Glomerular filtration rate (GFR) percentages (postoperative value divided by preoperative value), blood urea nitrogen (BUN)/creatinine ratios, and serum creatinine percentages were compared at 2 weeks, 6 months, and 1 year after surgery between users of NSAID and users of opioids for PCA. Additionally, postoperative complication rates, postoperative acute kidney injury (AKI) incidences, postoperative pain scores, and lengths of hospital stay were compared between groups. Postoperative GFR percentages, BUN/creatinine ratios, and serum creatinine percentages were similar between the two groups. There were no significant differences in the rates of postoperative complications, incidences of AKI, and pain scores at 30 min, 6 h, 48 h, or 7 days postoperatively. The length of hospital stay was significantly shorter in the NSAID group than in the opioid group. This study showed no association between the use of NSAID for PCA after laparoscopic nephrectomy and the incidence of postoperative renal dysfunction.

Intrathecal hydrophilic opioids for abdominal surgery: a meta-analysis, meta-regression, and trial sequential analysis

Background

Intrathecal hydrophilic opioids decrease systemic opioid consumption after abdominal surgery and potentially facilitate enhanced recovery. A meta-analysis is needed to quantify associated risks and benefits.

Methods

A systematic search was performed to find RCTs investigating intrathecal hydrophilic opioids in abdominal surgery. Caesarean section and continuous regional or neuraxial techniques were excluded. Several subgroup analyses were prespecified. A conventional meta-analysis, meta-regression, trial sequential analysis, and provision of GRADE scores were planned.

Results

The search yielded 40 trials consisting of 2500 patients. A difference was detected in ‘i.v. morphine consumption’ at Day 1 {mean difference [MD] −18.4 mg, (95% confidence interval [CI]: −22.3 to −14.4)} and Day 2 (MD −25.5 mg [95% CI: −30.2 to −20.8]), pain scores at Day 1 in rest (MD −0.9 [95% CI: −1.1 to −0.7]) and during movement (MD −1.2 [95% CI: −1.6 to −0.8]), length of stay (MD −0.2 days [95% CI: −0.4 to −0.1]) and pruritus (relative risk 4.3 [95% CI: 2.5–7.5]) but not in nausea or sedation. A difference was detected for respiratory depression (odds ratio 5.5 [95% CI: 2.1–14.2]) but not when two small outlying studies were excluded (odds ratio 1.4 [95% CI: 0.4–5.2]). The level of evidence was graded as high for morphine consumption, in part because the required information size was reached.

Conclusions

This study showed important opioid-sparing effects of intrathecal hydrophilic opioids. Our data suggest a dose-dependent relationship between the risk of respiratory depression and the dose of intrathecal opioids. Excluding two high-dose studies, intrathecal opioids have a comparable incidence of respiratory depression as the control group.

Clinical trial registration

PROSPERO-registry: CRD42018090682.

Real-world use of the sufentanil sublingual tablet system for patient-controlled management of acute postoperative pain: a prospective noninterventional study

Objective: To evaluate the real-life effectiveness, safety, tolerability and patient-reported outcomes (PRO) of the sufentanil sublingual tablet system (SSTS) for postoperative pain management (POPM).Methods: This prospective, multicenter, noninterventional, study included adults with acute moderate to severe postoperative pain who self-administered sufentanil using the SSTS. Main outcome measures were pain intensity at rest (numerical rating scale [NRS]: 0 [no pain] to 10 [most intense pain imaginable]); most intense pain intensity (0-10); 4-point patient assessment of the pain control method ("excellent", "good", "fair", "poor"); patient satisfaction with the pain control level and the method of administration of pain medication (6-point scale: "extremely satisfied", "very satisfied", "satisfied", "dissatisfied", "very dissatisfied", "extremely dissatisfied"). Adverse drug reactions were recorded.Results: The SSTS reduced resting pain intensity in patients (n = 341) from a mean ± SD NRS score of 5.2 ± 2.3 (at SSTS handover) to 1.8 ± 1.6 (3rd day after handover). The proportion of patients with severe pain (for the PRO measure "most intense pain") decreased steadily during the 72 hours of treatment. Overall, 87.1% of the patients reported the method of pain control to be "good" or "excellent"; 91.8% reported being "extremely/very satisfied" or "satisfied" with the level of pain control; and 95.9% were at least satisfied with the method of pain medication administration. SSTS safety and tolerability was typical for opioids and as described in the SSTS Summary of Product Characteristics.Conclusions: The SSTS is a valuable option for real-life POPM and is effective in a wide range of surgical procedures.

Influential factors of postoperative pain trajectories in patients receiving intravenous patient-controlled analgesia: a single-centre cohort study in Taiwan

OBJECTIVES

We aimed to investigate the factors associated with variations in postoperative pain trajectories over time in patients using intravenous patient-controlled analgesia (IV-PCA) for postoperative pain.

DESIGN

Retrospective cohort study.

SETTING

A single medical centre in Taiwan.

PARTICIPANTS

Patients receiving IV-PCA after surgery.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome was the postoperative pain scores.

RESULTS

A total of 3376 patients and 20 838 pain score observations were analysed using latent curve models. Female and longer anaesthesia time increased the baseline level of pain (p=0.004 and 0.003, respectively), but abdominal surgery and body weight decreased it (both p<0.001). Regarding the trend of pain resolution, lower abdominal surgery steepened the slope (p<0.001); older age, American Society of Anesthesiologists (ASA) class ≥3 and longer anaesthesia time tended to flatten the slope (p<0.001, =0.019 and <0.001, respectively). PCA settings did not affect the variations in postoperative pain trajectories.

CONCLUSIONS

Patient demographics, ASA class, anaesthesia time and surgical sites worked together to affect postoperative pain trajectories in patients receiving IV-PCA. Latent curve models provided valuable information about the dynamic and complex relationships between the pain trajectories and their influential factors.

Risk Factors for Moderate to Severe Pain during the First 24 Hours after Laparoscopic Bariatric Surgery While Receiving Intravenous Patient-Controlled Analgesia

Objective

To investigate the incidence of and risk factors for moderate to severe pain during the first 24 hours after laparoscopic bariatric surgery.

Materials and Methods

This retrospective study included morbidly obese patients who underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass at a single institution between June 2016 and July 2018. Demographic, clinical, operative, and postoperative pain data from the postanesthesia care unit (PACU) and ward were analyzed. Intravenous patient-controlled analgesia (IV-PCA) was commenced before PACU discharge.

Results

Ninety-seven patients were included. The mean age was 38.60 ± 12.27 years, and the mean BMI was 45.04 ± 8.42 kg/m², and 69% were female. The incidence of moderate to severe pain was 75%. Moderate to severe pain during the first 24 hours was associated with young age, female sex, postoperative administration of NSAIDs, first pain score greater than 3 on arrival at the PACU, and inadequate pain control at PACU discharge. A multivariate analysis revealed that inadequate pain control at PACU discharge was the only factor independently associated with moderate to severe pain during the first 24 hours postoperatively (p=0.011). From PACU discharge to the end of postoperative day 3, moderate to severe pain at the end of each 24-hour period was a significant predictor of moderate to severe pain in the subsequent 24-hour period (p=0.011, p < 0.001, and p=0.004, respectively).

Conclusions

Moderate to severe pain was experienced by 75% of patients undergoing laparoscopic bariatric surgery and receiving IV-PCA after PACU discharge. Inadequate pain control at PACU discharge was the only independent risk factor for moderate to severe pain during the first 24 hours postoperatively.

Dynamic predictive model for postoperative nausea and vomiting for intravenous fentanyl patient-controlled analgesia

Postoperative nausea and vomiting is the most common side-effect of opioid-based intravenous patient-controlled analgesia. Apfel's simplified risk score is popular but it has some limitations. We developed and validated a dynamic predictive model for nausea or vomiting up to 48 postoperative hours, available as an online web application. Fentanyl was used by 22,144 adult patients for analgesia after non-cardiac surgery under general anaesthesia: we randomly divided them into development (80%) and validation (20%) cohorts, repeated 100 times. We used linear discriminant analysis to select variables for multivariate logistic regression. The incidences of postoperative nausea or vomiting were: 0-48 h, 5691/22,144 (26%); 0-6 h, 2749/22,144 (12%); 6-12 h, 2687/22,144 (12%); 12-18 h, 2624/22,144 (12%); 18-24 h, 1884/22,144 (9%); and 24-48 h, 1082/22,144 (5%). The median (95%CI) area under the receiver operating characteristic curve was 0.72 (0.71-0.73) up to 48 postoperative hours compared with 0.65 (0.64-0.66) for the Apfel model, p < 0.001. The equivalent areas for 0-6 h, 6-12 h, 12-18 h, 18-24 h and 24-48 h were: 0.70 (0.69-0.72); 0.71 (0.69-0.73); 0.69 (0.68-0.71); 0.70 (0.67-0.72); and 0.69 (0.66-0.71), respectively. Our web application allows clinicians to calculate incidences of nausea and vomiting in patients receiving intravenous fentanyl for patient-controlled analgesia.

Caffeine attenuates seizure and brain mitochondrial disruption induced by Tramadol: the role of adenosinergic pathway

Tramadol (TR) is an analgesic drug used to treat moderate-to-severe pain but it induces seizure even at therapeutic doses. The exact mechanism of TR-inducing seizure is not clear but inhibition of the serotonin, GABA, and nitrous oxide (NOS) pathways are the commonly proposed mechanisms. Adenosinergic system has a crucial function in the modulation of seizure. Also, oxidative damage is an unavoidable effect of the seizure. This study was conducted to evaluate the role of the adenosinergic system on the seizure and oxidative stress biomarkers induced by TR using antagonist of the adenosinergic receptors in the Albino mice. For that purpose, generated clonic seizure, as seizure threshold, was evaluated by TR. Caffeine (CAF; 8 mg/kg, i.p.), a nonselective antagonist of adenosine receptors, was administered 1 hour before the seizure induction. The seizure threshold significantly increased by CAF-treated group when compared to TR group (p < 0.001). Oxidative stress biomarkers such as reactive oxygen species, protein carbonyl content, and lipid peroxidation significantly decreased and glutathione content significantly increased by CAF in brain mitochondria compared to the TR group, whereas oxidative biomarkers significantly increased in the TR group compared to the control group. The results of the present study suggested that the adenosinergic system is involved in seizure induced by TR and meanwhile, inhibition of adenosine receptors can decrease the TR seizure threshold and also decrease the induced oxidative damage in the brain mitochondria.

Comprehensive Perioperative Management Considerations in Patients Taking Methadone

PURPOSE OF REVIEW

Well-informed staff can help decrease risks and common misconceptions regarding opioid-tolerant patients, especially those taking methadone.

RECENT FINDINGS

In 2015, opioid pain relievers were the second most used drug at 3.8 million. Overdose death was three times greater in 2015 than in 2000. Medication-assisted treatment was sought by more than 2 million individuals with substance use disorder, one of which is methadone. Chronic pain affects millions of adults in the USA. Opioid therapy is widely used among these adults. Related to the risk of abuse and dependence, guidelines suggest that opioid therapy may not be considered first-line treatment. A multidisciplinary approach, including thorough preoperative evaluation, the utilization of multimodal pain management strategies, and opioid-sparing techniques in both the intraoperative and postoperative periods will allow for the best possible outcome.

Thoracic epidural analgesia (TEA) versus patient-controlled analgesia (PCA) in laparoscopic colectomy: a systematic review and meta-analysis

PURPOSE

A meta-analysis of RCTs was designed to provide an up-to-date comparison of thoracic epidural analgesia (TEA) and patient-controlled analgesia (PCA) in laparoscopic colectomy.

METHODS

Our study was completed following the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. A systematic literature screening was performed in MEDLINE and Web of Science. Fixed effects (FE) or random effects (RE) models were estimated based on the Cochran Q test result.

RESULTS

Totally, 8 studies were introduced in the present meta-analysis. Superiority of PCA in terms of length of hospital stay (LOS) (WMD 0.73, p = 0.004) and total complication rate (OR 1.57, p = 0.02) was found. TEA had a lower resting pain visual analogue scale (VAS) score at Day 1 (WMD - 2.23, p = 0.005) and Day 2 (WMD - 2.17, p = 0.01). TEA group had also a systematically lower walking VAS. Moreover, first bowel opened time (first defecation) (WMD - 0.88, p < 0.00001) was higher when PCA was applied.

CONCLUSIONS

TEA was related to a lower first bowel opened time, walking, and resting pain levels at the first postoperative days. However, the overall complication rate and LOS were higher in the epidural analgesia group. Thus, for a safe conclusion to be drawn, further randomized controlled trials (RCTs) of a higher methodological and quality level are required.

Comparison of the Analgesic Effect of Sufentanil versus Fentanyl in Intravenous Patient-Controlled Analgesia after Total Laparoscopic Hysterectomy: A Randomized, Double-blind, Prospective Study

Background: Fentanyl is one of the most widely used opioids for intravenous patient-controlled analgesia (IV-PCA). Sufentanil, a fentanyl analog, is suitable for postoperative pain control because it has no active metabolites and shows a higher therapeutic index and lower frequency of respiratory suppression than fentanyl. This study aimed to compare the two opioids for postoperative pain relief on the basis of analgesic efficacy, adverse effects, and patient satisfaction. Methods: Sixty-four patients undergoing total laparoscopic hysterectomy were randomly allocated into a fentanyl group (n = 31) or a sufentanil group (n = 33). The patients received 50-μg fentanyl or 10-μg sufentanil before induction of anesthesia and 5 minutes after uterine incision during surgery in the fentanyl and sufentanil group, respectively. After arriving at the post-anesthesia care unit (PACU), verbal pain score (VPS) and sedation score were assessed. IV-PCA (fentanyl 1250 μg or sufentanil 250 μg with ondansetron 8 mg; total volume, 60 ml) was connected and continued for 48 h postoperatively. Postoperative pain was evaluated by using the numeric rating scale (NRS; at rest/during cough) at 6, 12, 24, 36, and 48 hours after surgery. The cumulative PCA consumption, patient satisfaction scores, and adverse effects were measured. Results: In the PACU, VPS was significantly higher and rescue fentanyl consumption was higher in the fentanyl group than in the sufentanil group, while the sedation score and adverse effects were comparable between the groups. No significant differences were observed in the NRS scores for pain (at rest/during cough) in the ward over 48 hours postoperatively, but the cumulative PCA consumption was significantly higher in the fentanyl group (47.4 ± 9.9 ml vs. 36.2 ± 14.6 ml, P = 0.01). There were no significant intergroup differences in patient satisfaction score and the incidence of adverse effects in the ward, except for a higher incidence of dry mouth in the fentanyl group. Conclusions: In comparison with fentanyl, sufentanil showed comparable analgesic efficacy and safety with less analgesic consumption (under a potency ratio of 1:5) in IV-PCA after total laparoscopic hysterectomy. Therefore, we suggest that sufentanil can be a useful alternative to fentanyl for IV-PCA.

Is the transdermal fentanyl patch an efficient way to achieve acute postoperative pain control?: A randomized controlled trial

BACKGROUPD

This study investigated the plasma fentanyl concentration and efficacy of transdermal fentanyl patch (TFP) (25 μg/h) in the management of acute postoperative pain.

METHODS

Patients undergoing laparoscopic cholecystectomy were randomly allocated to 2 groups. The TFP group (n = 30) received a single TFP 25 μg/ h to the anterior chest wall 14 h before operation. The IV group (n = 30) received a placebo patch. After the operation, intravenous fentanyl infusion (25 μg/h) was begun with loading dose 25 μg in the IV group and only normal saline in the TFP group. Plasma fentanyl levels were measured at admission, 1, 6, 12, 24, and 48 h postoperatively. Pain severity and adverse effects were evaluated too.

RESULTS

The fentanyl level peaked 1 h after operation in the TFP group (3.27 ± 0.34 ng/mL) and 24 h postoperatively in the IV group (2.9 ± 0.42 ng/mL). Pain scores and the use of rescue analgesics were not significantly different between 2 groups. Respiratory depression was not happened in both groups.

CONCLUSIONS

The TFP (25 μg/h) affixed 14 h before surgery reached a higher constant concentration than the same dose setting of a constant IV infusion of fentanyl after surgery. Although the concentration of fentanyl was higher than those of previous researches, there was no respiratory depression. But, there was no advantage of reducing pain score and the use of rescue analgesics.

CLINICAL TRIAL REGISTRATION

(available at: http://cris.nih.go.kr, KCT0002221).

Patient-controlled paravertebral analgesia for video-assisted thoracoscopic surgery lobectomy

Background

Paravertebral block has been proven to be an efficient method to provide post-thoracotomy pain management. This study aimed to compare patient-controlled paravertebral analgesia (PCPA) and intravenous patient-controlled analgesia (IVPCA) in terms of analgesic efficiency, respiratory function, and adverse effects after video-assisted thoracoscopic surgery (VATS) lobectomy.

Patients and methods

The prospective randomized trial study was carried out on 60 patients who underwent VATS lobectomy (randomly allocated 30 patients in each group). In the PCPA group, an initial dose of 0.3 mL/kg of 0.125% bupivacaine with fentanyl 2 µg/mL was administered, followed by a 3 mL/h continuous infusion with patient-controlled analgesia (2 mL bolus, 10-minute lockout interval, 25 mL/4 h limit). In the IVPCA group with morphine 1 mg/mL solution, an infusion device was programmed to deliver a 1.0 mL demand bolus with no basal infusion rate, with a 10-minute lockout interval and a maximum of 20 mL/4 h period. Postoperative pain was assessed by visual analog scale at rest and on coughing. Arterial blood gas and spirometry were monitored and recorded for the first 3 postoperative days. Side effects to include were also recorded.

Results

The PCPA group had statistically significant lower pain scores (P<0.0001) at rest at all times. Lower pain scores on coughing were statistically significant in PCPA group in the first 4 hours. Postoperative spirometry showed that both the groups had comparable recovery trajectories for their pulmonary function. Arterial blood gas analysis showed pH and PaCO₂ were in a normal range in both the groups. The incidence of headache was higher in the IVPCA group (13.3% vs 0%; P=0.038).

Conclusion

PCPA effectively managed pain after VATS lobectomy, with lower pain scores, similar respiratory function, and fewer side effects than standard IVPCA treatment.

Patient-controlled epidural analgesia versus conventional epidural analgesia after total hip replacement - a randomized trial

AIMS

Patient-controlled analgesia (PCA) is usually considered a better option for pain management compared to conventional analgesia. The beneficial effect of PCA has been assessed in a number of studies; however, the results are inconsistent. The goal of this study was to compare of patient-controlled epidural analgesia (PCEA) to conventional epidural analgesia after total hip replacement (THR).

METHODS

This prospective study was performed at the Department of Anesthesia and Intensive Care Medicine at a tertiary university hospital. After THR, patients were admitted to the intensive care unit (ICU) and randomized to one of two groups (PCEA and non-PCEA). Postoperative pain in the PCEA group was treated using a standardized protocol, while the analgesia in the non-PCEA group was based on physician prescription according to the patient's clinical condition. The total consumption of analgesics, patients' satisfaction, pain intensity, and analgesia-related complications were recorded for 24 h after surgery.

RESULTS

The final sample consisted of 111 patients (PCEA group, n=55 and non-PCEA group, n=56). The PCEA group had significantly lower total consumption of analgesic mixtures (0.9±0.3 and 1.3±0.4 mL/kg per day, P<0.001).There was greater patient satisfaction (P<0.001) in the PCEA group. The mean pain intensity over 24 hours postoperatively was similar for both groups (P=0.14). There was no significant difference in rate of analgesia-related complications between the groups (hypotension, P=0.14; bradypnea, P=0.11).

CONCLUSION

Compared to conventional epidural analgesia based on physician prescription, PCEA led to less total analgesic consumption and greater patient satisfaction after THR.

Dose determination of sufentanil for intravenous patient-controlled analgesia with background infusion in abdominal surgeries: A random study

Objectives

Sufentanil has been widely used in epidural PCA, while its use in intravenous PCA has rarely been reported. Based on its use in target controlled infusion, we reckoned that the effect-site concentration of sufentanil would be steady if background infusion is given in intravenous PCA. This prospective, single center, randomized study with a three arm parallel group design aims to find out the appropriate dose of sufentanil when used in intravenous PCA with background infusion in abdominal surgeries.

Methods

Patients diagnosed with gastrointestinal cancer and consented to the study were recruited. The analgesia pump with one of three different doses of sufentanil (1.5, 2.0 or 2.5 μg/kg) was attached to the patient through peripheral venous line right after surgery. The primary endpoint was pain scale VAS up to 48 hours postoperatively.

Results

In our study 90 patients were analyzed. In group B (SF 2.0) and C (SF2.5), patients had better pain relief than in group A (SF 1.5). There was no difference between group B and C in pain intensity at rest. While in group C more patients got pain relived at activity than in group B. All three groups had low and similar incidence of adverse effects of sufentanil.

Conclusion

The dose 2.5 μg/kg of sufentanil with background infusion is preferred because of better pain alleviation at activity without increase of adverse effects up to 48 hours after surgery.

Patient-Controlled Analgesia and Length of Hospital Stay in Orthognathic Surgery: A Randomized Controlled Trial

PURPOSE

The objective of this prospective, randomized controlled pilot study of patients undergoing orthognathic surgery was to compare the hospital length of stay (LOS) in patients using intravenous patient-controlled analgesia (PCA) versus patients receiving scheduled and as-needed oral analgesia.

PATIENTS AND METHODS

A total of 40 patients (19 male and 21 female patients) aged 16 to 56 years (mean, 20.73 years; standard deviation, 6.87 years) were recruited prospectively and randomized to PCA and non-PCA groups of equal size. Recording of the patient-reported pain score using a visual analog scale was commenced at 8:00 am on day 1 after surgery until discharge. The pain score from routine nursing observations during the postoperative period was recorded until the patient was discharged from the hospital.

RESULTS

Randomization resulted in approximately equal proportions of male patients (45% vs 50%) and median ages (18.5 years vs 20 years) for the PCA group versus the non-PCA group; however, the PCA group was noted to have a higher proportion of double-jaw surgery (65% vs 40%). The median LOS was 2 days for both the PCA and non-PCA groups (P = .06). No statistically significant difference in pain scores was found between the 2 groups either at rest (P = .27) or on movement (P = .13).

CONCLUSIONS

No evidence was found to indicate the superiority of either the PCA or non-PCA regimen with respect to LOS and pain scores; however, this is not evidence of equivalence of the 2 pain management approaches.

Magnesium sulphate improves pulmonary function after video-assisted thoracoscopic surgery: A randomised double-blind placebo-controlled study

BACKGROUND

Reduced lung volumes are unavoidable after lung resection surgery. Magnesium sulphate (MgSO4) administration has been reported to reduce the requirement for neuromuscular blocking drugs and postoperative analgesics in surgical patients.

OBJECTIVE

To investigate the effect of MgSO4 on pulmonary function after video-assisted thoracoscopic surgery (VATS).

DESIGN

A randomised, double-blind, placebo-controlled trial.

SETTING

A university tertiary care centre.

PATIENTS

Sixty-six patients scheduled for pulmonary lobectomy or segmentectomy via VATS.

INTERVENTION

Patients were allocated to one of two groups: the Mg (MgSO4 50 mg kg intravenously for 10 min, followed by a continuous infusion of 15 mg kg h during surgery) or the control (same volume of 0.9% saline).

MAIN OUTCOME MEASURES

Pulmonary function tests [forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and peak expiratory flow rate] were measured before surgery and at three time points after surgery (2, 24 and 48 h postoperatively) using a portable spirometer. Twelve months after surgery, pulmonary function test values were repeated at a regular outpatient follow-up visit.

RESULTS

FEV1 at 24 (1.7 ± 0.6 vs. 1.3 ± 0.5 l, P = 0.033) and 48 h (1.7 ± 0.6 vs. 1.4 ± 0.5 l, P = 0.021) and FVC at 24 (2.0 ± 0.8 vs. 1.6 ± 0.6 l, P = 0.038) and 48 h (2.2 ± 0.8 vs. 1.7 ± 0.7 l, P = 0.008) after surgery were significantly greater in the Mg group. Patients in the Mg group required less rocuronium than those in the control group (64.2 ± 19.9 vs. 74.9 ± 20.3 mg, respectively; P = 0.041). Consumption of postoperative patient-controlled analgesia was also significantly less at 24 and 48 h after surgery in the Mg group (P = 0.022 and 0.015, respectively), although pain scores and rescue analgesics were comparable. Five patients in the control group were diagnosed with postoperative pneumonia using clinical and radiological criteria before discharge. FEV1 and FVC at 12 months after surgery were not different between the two groups.

CONCLUSION

Intraoperative administration of MgSO4 improved pulmonary function and reduced the need for rocuronium and postoperative analgesics in patients who underwent VATS.

TRIAL REGISTRATION

cris.nih.go.kr identifier: KCT0001410.

Efficacy of perineural dexamethasone with ropivacaine in thoracic paravertebral block for postoperative analgesia in elective thoracotomy: a randomized, double-blind, placebo-controlled trial

Purpose

The purpose of this study was to assess the efficacy of perineural dexamethasone with ropivacaine in multimodal analgesia for thoracic paravertebral block (TPVB) in patients undergoing elective thoracotomy.

Patients and methods

Ninety-six patients undergoing thoracotomy were enrolled in this trial and randomized to adjuvant therapy for TPVB: group S (saline), group R (0.5% ropivacaine), or group RD (5 mg dexamethasone and 0.5% ropivacaine). Postoperative analgesia, recovery duration, and chronic pain were recorded.

Results

Groups R and RD spent less time in the postanaesthesia care unit, had earlier out-of-bed activity, and had shorter postoperative hospital stays compared with group S. The RD group regained consciousness faster and had lower acute pain scores and used less patient-controlled analgesia during the first 72 h after surgery compared with group S. Postthoracotomy pain was decreased in group RD (19.0%) compared with group S (47.6%) 3 months postoperatively, p = 0.050.

Conclusion

Perineural dexamethasone with ropivacaine for TPVB improves postoperative analgesia quality, reduces recovery time, and may decrease the incidence of chronic pain after thoracotomy with an opioid-based anesthetic regimen.

Assessment and pathophysiology of pain in cardiac surgery

Analysis of the problem of surgical pain is important in view of the fact that the success of surgical treatment depends largely on proper pain management during the first few days after a cardiosurgical procedure. Postoperative pain is due to intraoperative damage to tissue. It is acute pain of high intensity proportional to the type of procedure. The pain is most intense during the first 24 hours following the surgery and decreases on subsequent days. Its intensity is higher in younger subjects than elderly and obese patients, and preoperative anxiety is also a factor that increases postoperative pain. Ineffective postoperative analgesic therapy may cause several complications that are dangerous to a patient. Inappropriate postoperative pain management may result in chronic pain, immunosuppression, infections, and less effective wound healing. Understanding and better knowledge of physiological disorders and adverse effects resulting from surgical trauma, anesthesia, and extracorporeal circulation, as well as the development of standards for intensive postoperative care units are critical to the improvement of early treatment outcomes and patient comfort.

Time-dependent analysis of dosage delivery information for patient-controlled analgesia services

Pain relief always plays the essential part of perioperative care and an important role of medical quality improvement. Patient-controlled analgesia (PCA) is a method that allows a patient to self-administer small boluses of analgesic to relieve the subjective pain. PCA logs from the infusion pump consisted of a lot of text messages which record all events during the therapies. The dosage information can be extracted from PCA logs to provide easily understanding features. The analysis of dosage information with time has great help to figure out the variance of a patient’s pain relief condition. To explore the trend of pain relief requirement, we developed a PCA dosage information generator (PCA DIG) to extract meaningful messages from PCA logs during the first 48 hours of therapies. PCA dosage information including consumption, delivery, infusion rate, and the ratio between demand and delivery is presented with corresponding values in 4 successive time frames. Time-dependent statistical analysis demonstrated the trends of analgesia requirements decreased gradually along with time. These findings are compatible with clinical observations and further provide valuable information about the strategy to customize postoperative pain management.

Safety of Patient-Controlled Analgesia After Surgery in Children And Adolescents: Concerns And Potential Solutions

Patient-controlled analgesia (PCA) is common practice for acute postoperative pain management. Postoperative PCA use decreases pain intensity and improves patient satisfaction when compared to non-PCA routes of medication administration. Although PCA has several advantages regarding efficacy and safety, adverse events remain a concern. Programming errors and protocols, patient monitoring, and PCA by proxy or with continuous infusion are recurring silent dangers of PCA use in children and adolescents. Innovative considerations need to be emphasized for future improvement of PCA devices for elective surgical patients. With technology within the healthcare setting advancing at a fast pace, smart pump technology is something to look forward to.

Perioperative pain management following total joint arthroplasty: A review and update to an institutional pain protocol

As the rate of total joint arthroplasty increases with the aging population of the United States, new focus on decreasing opioid use through the development of multimodal pain regimens (MPRs) is becoming an important area of research. MPRs use different agents and modes of delivery in order to synergistically address pain at many levels of the pain pathway. MPRs include a combination of acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), gabapentinoids, opioids (short- and long-acting), spinal/epidural analgesia, regional nerve blocks, and local anesthetics. This review summarizes the available literature on major components of MPRs shown to be effective in the total joint arthroplasty population. Finally, the authors' preferred method for pain control in the TJA population is reviewed.

Perioperative Pain Management in Hip and Knee Arthroplasty

Total hip and knee arthroplasty is associated with significant perioperative pain, which can adversely affect recovery by increasing risk of complications, length of stay, and cost. Historically, opioids were the mainstay of perioperative pain control. However, opioids are associated with significant downsides. Preemptive use of a multimodal pain management approach has become the standard of care to manage pain after hip and knee arthroplasty. Multimodal pain management uses oral medicines, peripheral nerve blocks, intra-articular injections, and other tools to reduce the need for opioids. Use of a multimodal approach promises to decrease complications, improve outcomes, and increase patient satisfaction after hip and knee arthroplasty.

Serial Analgesic Consumptions and Predictors of Intravenous Patient-controlled Analgesia with Cluster Analysis

Objectives:

To elucidate the dynamics of analgesic consumption regarding intravenous patient controlled analgesia (IVPCA) during postoperative period is rather complex partly due to between-patient variation and partly due to within-patient variation. A statistical method was proposed to classify serial analgesic consumption into different classifications that were further taken as the multiple outcomes on which to explore the associated predictors.

Methods:

We retrospectively included 3284 patients administrated by IVPCA for 3 days after surgery. A repeated measurement design corresponding to serial analgesic consumption variables defined as six-hour total analgesic consumptions was adopted. After determining the numbers of clusters, serial analgesic consumptions were classified into several homogeneous subgroups. Factors associated with new classifications were identified and quantified with a multinominal logistic regression model.

Results:

Three distinct analgesic classifications were aggregated, including “high”, ”middle” and “low” level of analgesic consumption of IVPCA. The mean analgesic consumptions on 12 successive analgesic consumptions at 6-hour interval of each classification consistently revealed a decreasing trend. As the trends were almost parallel with time, this suggests the time-invariant proportionality of analgesic consumption between the levels of analgesic consumption of IVPCA. Patient’s characteristics, like age, gender, weight, height, and cancer status, were significant factors associated with analgesic classifications. Surgical sites had great impacts on analgesic classifications.

Discussion:

The serial analgesic consumptions were simplified into 3 analgesic consumptions classifications. The identified predictors are useful to recognize patient’s analgesic classifications before using IVPCA. This study explored a new approach to analysing dynamic changes of postoperative analgesic consumptions.

Multimodal Analgesia, Current Concepts, and Acute Pain Considerations

PURPOSE OF REVIEW

Management of acute pain following surgery using a multimodal approach is recommended by the American Society of Anesthesiologists whenever possible. In addition to opioids, drugs with differing mechanisms of actions target pain pathways resulting in additive and/or synergistic effects. Some of these agents include alpha 2 agonists, NMDA receptor antagonists, gabapentinoids, dexamethasone, NSAIDs, acetaminophen, and duloxetine.

RECENT FINDINGS

Alpha 2 agonists have been shown to have opioid-sparing effects, but can cause hypotension and bradycardia and must be taken into consideration when administered. Acetaminophen is commonly used in a multimodal approach, with recent evidence lacking for the use of IV over oral formulations in patients able to take medications by mouth. Studies involving gabapentinoids have been mixed with some showing benefit; however, future large randomized controlled trials are needed. Ketamine is known to have powerful analgesic effects and, when combined with magnesium and other agents, may have a synergistic effect. Dexamethasone reduces postoperative nausea and vomiting and has been demonstrated to be an effective adjunct in multimodal analgesia. The serotonin-norepinephrine reuptake inhibitor, duloxetine, is a novel agent, but studies are limited and further evidence is needed. Overall, a multimodal analgesic approach should be used when treating postoperative pain, as it can potentially reduce side effects and provide the benefit of treating pain through different cellular pathways.

Spinal versus general anesthesia for transabdominal preperitoneal (TAPP) repair of inguinal hernia: Interim analysis of a controlled randomized trial

BACKGROUND

General anesthesia has been used as standard for laparoscopic hernia repair by the transabdominal preperitoneal (TAPP) approach. Regional anesthesia has been occasionally applied in high risk patients where general anesthesia is contraindicated. This randomized clinical trial compares spinal anesthesia with general anesthesia for TAPP inguinal hernia repair in non-high risk patients.

METHODS

Seventy adult American Society of Anesthesiologists I, II and III patients undergoing elective TAPP inguinal hernia repair were randomized to either general or spinal anesthesia.

RESULTS

Postoperative morphine consumption was significantly less immediately postoperatively (p < 0.001) in the spinal anesthesia group. Postoperative pain was also significantly decreased within the first 8 h postoperatively (p < 0.05) in the spinal anesthesia group.

CONCLUSIONS

Spinal anesthesia offers some advantages in patient analgesia during the early postoperative period after TAPP inguinal hernia repair and can be proposed as an effective alternative method of anesthesia for TAPP repair.

Implantable polymeric microneedles with phototriggerable properties as a patient-controlled transdermal analgesia system

Adequate pain control can be achieved using a patient-controlled drug delivery system that can provide analgesia to patients as needed. To achieve this objective, we developed a phototriggered microneedle (MN) system that enables the on-demand delivery of pain medications to the skin under external near-infrared (NIR) light stimulation. In this system, polymeric MNs, containing NIR absorbers and analgesics, are combined with a poly(l-lactide-co-d,l-lactide) supporting array. A "removable design" of the supporting array enables the quick implantation of the MNs into the skin to act as a drug depot, thus shortening the patch application time. Upon irradiation with NIR light, the NIR absorbers in the implanted MNs can absorb light energy and induce a phase transition in the MNs to activate drug release. We demonstrated that lidocaine release can be modulated or repeatedly triggered by varying the duration of irradiation and controlling the on and off status of the laser. Lidocaine delivered by the implanted MNs can be rapidly absorbed into the blood circulation within 10 min and has a bioavailability of at least 95% relative to the subcutaneous injection, showing that the proposed system has the potential to provide a rapid onset of pain relief. Such an implantable device may allow pain sufferers receiving the painkiller without the need for multiple needle injections, and may enable controlling pain more conveniently and comfortably.

Spinal fentanyl vs. sufentanil for post-operative analgesia after C-section: a double-blinded randomised trial

BACKGROUND

Fentanyl and sufentanil are the most commonly administered intrathecal lipophilic opioids worldwide, although their relative efficacy when given by this route is not well characterised. The primary endpoint of this prospective, randomised, double-blind study was to compare effective analgesia duration of intrathecal administered fentanyl 25 μg and sufentanil 2.5 or 5 μg, Second endpoints were to compare post-operative morphine consumption and incidence of side effects between these opioids dosages.

METHODS

After IRB approval, 180 full-term parturients undergoing elective Caesarean section were randomly allocated into three groups, according to the opioid added to 10 mg intrathecal hyperbaric bupivacaine: fentanyl 25 μg, sufentanil 2.5 μg or sufentanil 5 μg. Total effective analgesia was defined as time from spinal injection (T0) to first IV morphine requirement (T1) administered with a patient controlled intravenous pump. Statistical data analysis included non-parametric tests and chi-squared. A P value < 0.05 was considered statistically significant. Data are presented as median [interquartile ranges 25-75].

RESULTS

Duration of analgesia was significantly longer with sufentanil 2.5 μg (214 min [189-251]) and 5 μg (236 min [190-372]) compared to fentanyl 25 μg (187 min [151-230]) (P < 0.01). Morphine consumption at T1 + 4 h was lower in the sufentanil groups (6 mg [3-9] and 6 mg [2-10]) than in the fentanyl group (9 mg [5-13]) (P < 0.01). Incidence of adverse effects was not different between groups.

CONCLUSION

In the conditions of our study, sufentanil 5 μg was the opioid of choice, associated with the best quality of anaesthesia without increased incidence of side effects.

Common Pitfalls in Anesthesia for Noncardiac Thoracic Surgery

Over the past few decades, major surgical procedures involving the thorax have become commonplace at most larger medical facilities. Advances in perioperative care have allowed surgeons to perform increasingly complex procedures. These procedures are being performed on more seriously ill patients who are at increased risk for significant complications. Recent advances should help the anesthesiologist avoid some of the pitfalls in managing these complex patients. Preoperative assessment aids in the identification of patients at highest risk for intraoperative and postoperative events. Particular attention is given to myasthenia gravis, as thymectomy is among the most common surgical procedures that are performed in these patients. Aggressive pain control techniques, including neuraxial opioids and patient-controlled analgesia, where appropriate, not only improve patient comfort but can improve postoperative pulmonary function. Advances in techniques for providing one-lung ventilation allow the anesthesiologist more options to individualize management for each clinical scenario. Careful fluid management may help to minimize the risk of postoperative pulmonary complications. A basic understanding of video-assisted thoracic surgery should help the anesthesiologist provide optimal surgical conditions and perioperative care. Recent advances demand a greater role for the anesthesiologist if the best outcomes are to be achieved in patients undergoing thoracic procedures.