Postsurgical Analgesic Effectiveness of Ultrasound-Guided Parasternal Block After Auricular Reconstruction Using Autologous Costal Cartilage in Pediatric Patients: A Randomized Controlled Trial

OBJECTIVE

To study the efficacy of ultrasound-guided parasternal block (US-PSI) in pediatric patients undergoing auricular reconstruction surgery.

METHODS

For this study, the authors recruited 60 children between the ages of 5 and 12 years who underwent auricular reconstruction with autologous costal cartilage (ACC) to correct microtia. They were randomized to receive either ultrasound-guided modified parasternal block or periprostatic local infiltration anesthesia (PLIA), with 30 cases in each group. Ultrasound-guided parasternal block was administered following anesthesia induction, whereas PLIA was administered after ACC harvest. Lastly, following surgery, all children were provided with patient-controlled intravenous analgesia with sufentanil, and the numeric pain rating scale (NRS) was used to assess the intensity of pain. Our primary outcomes were the resting NRS pain scores and the NRS scores upon coughing at 1, 6, 12, 24, and 48 hours postsurgery. Sufentanil consumption within the first 24 hours of surgery, the mean duration to first ambulation, and the usage of rescue analgesics were our secondary outcomes. The authors also recorded the occurrence of undesirable side effects as well as more serious side effects like pneumothorax.

RESULTS

Pediatric patients who were administered US-PSI showed significantly reduced NRS chest pain scores at 6 and 12 hours postsurgery compared to those who received PLIA (P<0.05). In addition, sufentanil consumption within the first 24 hours postsurgery, duration to first ambulation, and use of rescue analgesics were significantly lower among patients in the US-PSI group when compared to those in the PLIA group (P<0.05).

CONCLUSIONS

This study found that US-PSI was a highly efficacious and safe technique for postsurgical analgesia following auricular reconstruction with ACC in pediatric patients.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Comparison of postoperative analgesia and side effects in pediatric laparoscopic surgery with morphine and nalbuphine

There is currently no consensus on the optimal perioperative pain management strategy involving specific opioids. This study aims to compare the postoperative analgesia, the associated side effects between nalbuphine and morphine in children undergoing laparoscopic surgery. One hundred ninety children were randomly assigned to nalbuphine (0.2 mg/kg) or morphine (0.2 mg/kg). Nalbuphine's analgesic effect was non-inferior to morphine, with similar total rescue analgesic consumption during PACU stay (0.03 ± 0.05mg vs. 0.04 ± 0.06 mg, p > 0.05). Nalbuphine group had a lower incidence of respiratory depression (RR ≤ 10/min) (4.8% vs. 38.6%, p < 0.001), PONV (2.4% vs. 18.1%, p = 0.002), and pruritus (0% vs. 16.9%, p < 0.001) than morphine. Additionally, nalbuphine showed a shorter laryngeal mask airway removal time (13.9 [12.7, 15.1]) compared with morphine (17.0 [15.1, 18.9], p = 0.011). Nalbuphine provides equipotent analgesia with significantly lower incidences of respiratory depression, PONV, and pruritus compared with morphine in pediatric laparoscopic surgery.

Individual Factors Modifying Postoperative Pain Management in Elective Total Hip and Total Knee Replacement Surgery

Total hip and knee replacements are the most common orthopedic procedures performed due to osteoarthritis. Pain is an intrinsic symptom accompanying osteoarthritis, persisting long before surgery, and continuing during the preoperative and postoperative periods. Appropriate pain management after surgery determines the comfort, duration, and cost of hospitalization, as well as the effectiveness of postoperative rehabilitation. Individual differences in pain perception and tolerance in orthopedic patients remain an important research topic. Therefore, the aim of this study was to investigate the predictors of analgesic requirements (morphine, acetaminophen, and ketoprofen), including individual pain threshold and tolerance, body mass index (BMI), diabetes, and beliefs about pain control in patients undergoing elective hip or knee arthroplasty using a multilevel regression model (N = 147, 85 women, 62 men, 107 after hip replacement, and 40 after knee replacement). Results: Higher pain tolerance was associated with a lower dose of morphine per kg after surgery. Patients undergoing hip surgery received a lower dose of ketoprofen than patients undergoing knee surgery. The more the patient believed in personal pain control, the stronger the negative relationship between pain tolerance and morphine requirement. The lowest doses were given to patients with the highest pain tolerance and the greatest belief in personal control. Factors such as belief in pain control and pain tolerance should be considered in comprehensive postoperative pain management in orthopedic patients to reduce opioid doses and, thus, side effects.

Intrathecal Morphine and Post-Operative Pain Relief in Robotic Surgeries: A Systematic Review and Meta-Analysis

Despite the potential benefits of intrathecal morphine (ITM), the precise role and dosing of ITM in robotic assisted surgery (RAS) remains unclear. This systematic review explores real-world evidence to evaluate the efficacy and outcomes of ITM in patients undergoing RAS. In accordance with PRISMA guidelines, a comprehensive search was conducted on four databases: MEDLINE, Embase, Cochrane Library and APA PsycInfo. Primary outcomes included pain scores at rest and on exertion at 24- and 48-h time intervals, and secondary outcomes aimed to explore the side effects of ITM. A meta-analysis was conducted to determine mean differences. A risk of bias assessment was conducted via the Cochrane Risk of Bias 2 tool. A total of 9 RCTs involving 619 patients were included in this review, of which 298 patients were administered ITM. Significant pain score reductions were observed both at rest (MD = -27.15; 95% CI [-43.97, -10.33]; I2 = 95%; p = 0.002) and on exertion (MD = -25.88; 95% CI [-37.03, -14.72]; I2 = 79%; p = 0.0003) 24 h postoperatively in the ITM groups, accompanied by a notable decrease in postoperative IV morphine equivalent consumption at 24 h (MD = -20.13; 95% CI [-30.74, -9.52]; I2 = 77%; p = 0.0002). ITM improved pain scores both at rest and on exertion at 24 and 48 h intervals, concurrently reducing the need for postoperative opioid consumption, but at the cost of an increased incidence of adverse events.

Comparative analysis of opioid use in sickle cell crisis in an urban facility in Ghana

Vaso-occlusive crises (VOC) is common and opioids are the treatment of choice.This study compared parenteral pethidine and morphine in the elimination/reduction of pain in acute VOC to tolerable levels. This open-label randomized study compared intravenous morphine 5 mg 4 hourly to intramuscular pethidine 75 mg 4 hourly. Eighty-two consenting adult sickle cell disease participants were recruited from the Korle-Bu Polyclinic. (Forty-one participants in each arm). There were 42 male and 40 female participants. Median age was 25 years. Pethidine participants totalling 31.7% (13/41) and 53.7% (22/41) in the morphine arm had a sustained response within 6 h, p = 0.027. In the pethidine and morphine arms 60.0% (24/40) and 62.5% (25/40) of participants respectively achieved adequate pain control within 72 h of initiating therapy, p = 0.296. Most participants, 96.3% (79/82) had no side effects to opioids. The commonest side effects were generalized pruritus, nausea and vomiting, and headaches. More pethidine than morphine participants experienced side effects 29.3% and 22.0% respectively; p = 0.448. In conclusion, more morphine participants achieved a sustained pain response compared to the pethidine participants. There was no difference in the tolerability and side effect profile of the opioids. No participant experienced respiratory suppression.

New Perspective for Drug-Drug Interaction in Perioperative Period

In this review, we aim to discuss current information on drug interactions in the perioperative period. During this period, patients receive several drugs that may interact with each other and affect the efficacy and safety of the treatment. There are three types of drug interactions: pharmacodynamic, pharmacokinetic, and pharmaceutical. It is important to recognize that drug interactions may increase the toxicity of the drug or reduce its efficacy, increasing the risk of complications in the perioperative period. This review describes the most commonly used perioperative drugs approved by the FDA and some of the described interactions between them. Thoroughly reviewing a patient's medication list and identifying potential interactions are essential steps in minimizing risks. Additionally, vigilant monitoring of patients during and after surgery plays a pivotal role in early detection of any signs of drug interactions. This article emphasizes the significance of addressing DDIs in the perioperative period to ensure patient well-being and advocates for the implementation of careful monitoring protocols to promptly identify and manage potential interactions.

Short-acting versus long-acting opioids for pediatric postoperative pain management

INTRODUCTION

Opioids are potent analgesics commonly used to manage children's moderate to severe perioperative pain in children. A wide range of short and long-acting opioids are used to treat surgical pain and will be reviewed in this article.

AREAS COVERED

Both short- and long-acting opioids contain unique therapeutic benefits and adverse effects; however, due to the side effect profile and safety concerns, lack of familiarity, and evidence with long-acting opioids to treat surgical pain, shorter-acting opioids have traditionally been used in children. Almost all opioids work by binding to the mu receptor. Methadone, a long-acting opioid, is an exception because it also has beneficial N-methyl-D-aspartate antagonist properties. Clinically methadone's properties could translate to improved analgesic outcomes, reduced risk of adverse events, less risk for acute hyperalgesia, tolerance and abuse potential, faster recovery, and reduced risk for chronic persistent surgical pain. This review article summarizes and compares the evidence of commonly used short and long-acting opioids for perioperative pain control in the pediatric population.

EXPERT OPINION

Individualized methadone therapy using pharmacogenomics has the potential to transform opioid use in pain management by improving patient safety and analgesic outcomes, thereby addressing the gaps in current standardized ERAS protocols.

Health Status Perception and Psychological Sequelae in Buried Victims: An Observational Study on Survivors of the Earthquake in Amatrice (Italy), Three Years Later

INTRODUCTION

The extrication from rubble is particularly critical for the survival of the victims of an earthquake. Early repeated infusion of sedative agents (SAs) in the acute trauma phase may interfere with neural processes leading to posttraumatic stress disorder (PTSD).

STUDY OBJECTIVE

This study aimed to analyze the psychological status reported by the buried victims of the earthquake in Amatrice (August 24, 2016; Italy) by considering type of the SAs administered during the extrication maneuvers.

METHODS

This was an observational study on data from 51 patients directly rescued under the rubble during the earthquake in Amatrice. During extrication maneuvers, a moderate sedation was administered by titrating ketamine (0.3-0.5mg/kg) or morphine (0.1-0.15mg/kg) with respect to the Richmond Agitation and Sedation Scale (RASS; between -2 and -3) in buried victims.Three years following the rescue, the survivors were interviewed on their perceived health status and stress using a questionnaire which consisted of 17 items: the standard four-item set of healthy days core questions (CDC HRQOL-4); the 12-item General Health Questionnaire (GHQ-12); and in addition, survivors were asked if they had a diagnosis for anxiety, depression, or for PTSD.

RESULTS

The study analyzed data from the complete clinical documentation of 51 survivors; 30 were males and 21 females, with an average age of 52 years. Twenty-six (26) subjects were treated with ketamine, while 25 were treated with morphine, during the extrication procedures. Concerning the quality-of-life analysis, only 10 survivors out of 51 perceived their health status as good; the others reported psychological disorders. The GHQ-12 scores showed that all survivors had psychological distress with a mean total score of 22.2 (SD = 3.5). Eighteen (18) victims declared to have had a diagnosis of generalized anxiety (35%), while 29 were treated for depression (57%) and PTSD (57%) by a specialist. With regards to the perceived distress level and the anxiety disorder, this analysis showed significant associations with SAs used during extrication, with a better performance for ketamine than for morphine.

CONCLUSION

These findings suggest investigating whether early sedation with ketamine directly in the disaster setting may promote the prophylaxis and reduce the risk of developing trauma-related disorders (TRDs) on the buried victims of major natural disasters in future studies.

Single-shot spinal diamorphine for laparoscopic nephrectomy: A retrospective study

Single-shot spinal diamorphine is becoming common practice in urological surgery to aid post-operative pain; however, its safety and efficacy require investigation. This study is a retrospective analysis of 113 laparoscopic or robotic-assisted nephrectomies over 4 years under one consultant urologist. Data were collected on demographic, pre-operative scores, anaesthesia, surgical information, post-operative outcomes and opioid consumption. Two main groups were established: no spinal diamorphine (NSD) and spinal diamorphine (SD). Four subgroups were then created, separating those who received patient-controlled anaesthesia (PCA) or not: Group 1 [general anaesthetic (GA)]; Group 2 [GA and PCA]; Group 3 [GA and spinal diamorphine] and Group 4 [GA, spinal diamorphine and PCA]. Ninety-eight eligible patients were identified. At 6 hours, pain scores were significantly higher for all non-spinal groups (p < 0.05); at 9 h, pain scores were significantly higher in NSD patients compared to SD (p = 0.026); at 12 h, pain scores were significantly higher for NSD patients compared to SD (p = 0.024), and Group 1 compared to Group 3 (p = 0.023). Total opioid consumption in the first 24 h post-surgery was higher in Group 1 compared to Group 3 (p = 0.024). There was no higher incidence of urinary retention, or any neurological complications reported within the SD patients. The study found a reduction in post-operative pain scores with the use of spinal diamorphine prior to laparoscopic and robotic-assisted nephrectomies. The findings may also suggest that pre-operative spinal diamorphine use can reduce the total volume of opioids administered via other routes in the first 24 h post-operatively. It recommends its routine administration but encourages prospective investigation.

Clinical Update on Patient-Controlled Analgesia for Acute Postoperative Pain

Patient-controlled analgesia (PCA) is an effective method for controlling acute pain, including postoperative pain in adults and in children from five years of age, pain resulting from labor, trauma, or other medical situations, or chronic and malignant pain. The treatment consists of a mini-computer-controlled infusion pump permitting the administration of on-demand, continuous, or combined doses of analgesic (mainly opioid) variations in response to therapy, which allows pain to be significantly controlled. Intravenous (IV)-PCA minimizes individual pharmacodynamics and pharmacokinetic differences and is widely accepted as a reference method for mild or severe postoperative pain. IV-PCA is the most studied route of PCA; other delivery methods have been extensively reported in the literature. In addition, IV-PCA usually voids the gap between pain sensation and analgesic administration, permitting better recovery and fewer side effects. The most commonly observed complications are nausea and vomiting, pruritus, respiratory depression, sedation, confusion and urinary retention. However, human factors such as pharmacy preparation and device programming can also be involved in the occurrence of these complications, while device failure is much less of an issue.

Opioids for Treatment of Pre-hospital Acute Pain: A Systematic Review

INTRODUCTION

Acute pain is a frequent symptom among patients in the pre-hospital setting, and opioids are the most widely used class of drugs for the relief of pain in these patients. However, the evidence base for opioid use in this setting appears to be weak. The aim of this systematic review was to explore the efficacy and safety of opioid analgesics in the pre-hospital setting and to assess potential alternative therapies.

METHODS

The PubMed, EMBASE, Cochrane Library, Centre for Reviews and Dissemination, Scopus, and Epistemonikos databases were searched for studies investigating adult patients with acute pain prior to their arrival at hospital. Outcomes on efficacy and safety were assessed. Risk of bias for each included study was assessed according to the Cochrane approach, and confidence in the evidence was assessed using the GRADE method.

RESULTS

A total of 3453 papers were screened, of which the full text of 125 was assessed. Twelve studies were ultimately included in this systematic review. Meta-analysis was not undertaken due to substantial clinical heterogeneity among the included studies. Several studies had high risk of bias resulting in low or very low quality of evidence for most of the outcomes. No pre-hospital studies compared opioids with placebo, and no studies assessed the risk of opioid administration for subgroups of frail patients. The competency level of the attending healthcare provider did not seem to affect the efficacy or safety of opioids in two observational studies of very low quality. Intranasal opioids had a similar effect and safety profile as intravenous opioids. Moderate quality evidence supported a similar efficacy and safety of synthetic opioid compared to morphine.

CONCLUSIONS

Available evidence for pre-hospital opioid administration to relieve acute pain is scarce and the overall quality of evidence is low. Intravenous administration of synthetic, fast-acting opioids may be as effective and safe as intravenous administration of morphine. More controlled studies are needed on alternative routes for opioid administration and pre-hospital pain management for potentially more frail patient subgroups.

A Dive Into Oliceridine and Its Novel Mechanism of Action

The current state of the opioid epidemic has revealed the need of utilizing proper pain management, especially in the postoperative setting where there is overuse of potent analgesics. However, the adequate treatment of pain is necessary to reduce mortality and cost of burden while increasing recovery and improving quality of life. Treatment of pain can be difficult to standardize as the guidelines from the American Pain Society discuss the importance of tailoring treatment options based on a patient’s sensitivities and risk factors. An effective fast-acting analgesic with adequate potency and few adverse events is the key to alleviating acute pain. Oliceridine (Olinvyk^®, Trevena Inc., Chesterbrook, USA) is a novel G protein-biased μ-opioid receptor agonist designed to decrease opioid-related adverse events (ORAEs) compared to conventional opioids. This article discusses oliceridine’s novel mechanism of action and current place in therapy. After a literature search on clinicaltrials.gov, three clinical trials were analyzed to understand the safety and efficacy of oliceridine. These trials demonstrated a comparable efficacy to morphine with a decreased risk for serious adverse events. However, further studies need to be conducted to evaluate the true safety impact of oliceridine compared to conventional opioids. 

Postoperative breakthrough pain in paediatric cardiac surgery not reduced by increased morphine concentrations

BACKGROUND

Morphine is commonly used for postoperative analgesia in children. Here we studied the pharmacodynamics of morphine in children after cardiac surgery receiving protocolized morphine.

METHODS

Data on morphine rescue requirements guided by validated pain scores in children (n = 35, 3-36 months) after cardiac surgery receiving morphine as loading dose (100 μg kg^-1) with continuous infusion (40 μg kg^-1 h^-1) from a previous study on morphine pharmacokinetics were analysed using repeated time-to-event (RTTE) modelling.

RESULTS

During the postoperative period (38 h (IQR 23-46)), 130 morphine rescue events (4 (IQR 1-5) per patient) mainly occurred in the first 24 h (107/130) at a median morphine concentration of 29.5 ng ml^-1 (range 7-180 ng ml^-1). In the RTTE model, the hazard of rescue morphine decreased over time (half-life 18 h; P < 0.001), while the hazard for rescue morphine (21.9% at 29.5 ng ml^-1) increased at higher morphine concentrations (P < 0.001).

CONCLUSIONS

In this study on protocolized morphine analgesia in children, rescue morphine was required at a wide range of morphine concentrations and further increase of the morphine concentration did not lead to a decrease in hazard. Future studies should focus on a multimodal approach using other opioids or other analgesics to treat breakthrough pain in children.

IMPACT

In children receiving continuous morphine infusion, administration of rescue morphine is an indicator for insufficient effect or an event. Morphine rescue events were identified at a wide range of morphine concentrations upon a standardized pain protocol consisting of continuous morphine infusion and morphine as rescue boluses. The expected number of rescue morphine events was found to increase at higher morphine concentrations. Instead of exploring more aggressive morphine dosing, future research should focus on a multimodal approach to treat breakthrough pain in children.

Algorithm for management of an incarcerated inguinal hernia in the emergency settings with manual reduction. Taxis, the technique and its safety

BACKGROUND

An acute inguinal hernia remains a common emergency surgical condition worldwide. While emergency surgery has a major role to play in treatment of acute hernias, not all patients are fit for emergency surgery, nor are facilities for such surgery always available. Taxis is the manual reduction of incarcerated tissues from the hernia sack to its natural compartment, and can help delay the need for surgery from days to months. The aim of this study was to prepare a safe algorithm for performing manual reduction of incarcerated inguinal hernias in adults.

METHODS

Medline, Scopus, Ovid and Embase were searched for papers related to emergency inguinal hernias and manual reduction. In addition, the British National Formulary and Safe Sedation Practice for Healthcare Procedures: Standards and Guidance were reviewed.

RESULTS

A safe technique of manual reduction of an acute inguinal hernia, called GPS (Gentle, Prepared and Safe) Taxis, is described. It should be performed within 24 h from the onset of a painful irreducible lump in groin, and when concomitant symptoms and signs of bowel strangulation are absent. Conscious sedation guidelines should be followed. The most popular drug combination is of intravenous morphine and short-acting benzodiazepine, both titrated carefully for optimal and safe effect. The dose of drugs must be individualised, and the smallest effective dosage should be used to avoid oversedation. Following successful taxis, the patient should undergo a short period of observation. Urgent surgery can be undertaken during the same admission or up to several weeks later.

CONCLUSIONS

Taxis is a benign/non-invasive method for patients with an acute, non-strangulated inguinal hernias. It likely reduces the risk and complications of anaesthesia and surgery in the emergency settings. GPS Taxis should be considered as first line treatment in the majority of patients presenting with an acute inguinal hernia when existing bowel infarction is unlikely.

Review of the Physiology and Anesthetic Considerations for Pleuroscopy/Medical Thoracoscopy

Pleuroscopy or medical thoracoscopy is the second most common utilized procedure after bronchoscopy in the promising field of interventional pulmonology. Its main application is for the diagnosis and management of benign or malignant pleural effusions. Entry into the hemithorax is associated with pain and patient discomfort, whereas concurrently, notable pathophysiologic alterations occur. Therefore, frequently procedural sedation and analgesia is needed, not only to alleviate the patient's emotional stress and discomfort by mitigating the anxiety and minimizing the pain but also for yielding better procedural conditions for the operator. The scope of this review is to present the physiologic derangements occurring in pleuroscopy and compare the various anesthetic techniques and sedative agents that are currently being used in this context.

Intraoperative Methadone Use in Cardiac Surgery: A Systematic Review

OBJECTIVE

To investigate the effects of intraoperative methadone to standard of care opioids such as fentanyl and morphine on pain scores, opioid consumption, and adverse effects in adults undergoing cardiothoracic surgery.

METHODS

The literature was reviewed on PubMed, Embase, Cochrane Library, and Google Scholar, followed by a manual search using reference lists of the identified articles. Search terms included a combination of intraoperative methadone, methadone, and cardiac surgery. Our review includes four studies published between 2011 and 2020. Quality assessment of the studies was performed.

RESULTS

The initial search identified 715 articles with 461 duplicates removed, and 236 eliminated based on inclusion and exclusion criteria. Eighteen articles underwent full-text review. Four studies evaluating a total of 435 patients with various cardiothoracic procedures were included in this review. We found that intraoperative methadone decreases acute postoperative pain and reduces postoperative opioid consumption in the first 24 postoperative hours in patients who received 0.1-0.3 mg/kg intraoperative methadone in comparison to morphine and fentanyl. No difference was found in adverse effects between the groups. Quality assessment of the studies showed a low risk of bias in three of the randomized controlled trials and a high risk of bias in the retrospective review because of the baseline confounding bias in the study design.

CONCLUSIONS

Intraoperative methadone use reduces acute postoperative pain and lowers opioid consumption in comparison to morphine and fentanyl. Initial results suggest that methadone may be an equivalent opioid to be administered during cardiothoracic procedures to reduce acute post-surgical pain, though further research is warranted.

Continuous Pectoral Nerve Block Compared With Continuous Thoracic Paravertebral Block and Intravenous Opioid Analgesia for the Postoperative Analgesic Efficacy in Patients Undergoing Modified Radical Mastectomy: A Prospective Randomized Trial

OBJECTIVES

Postoperative pain following mastectomy is often severe and pain management is necessary. We evaluated the analgesic efficacy of continuous pectoral nerve block (PEC) in comparison with that of the continuous thoracic paravertebral block (TPVB) and the intravenous opioid analgesia in patients scheduled for modified radical mastectomy (MRM).

MATERIALS AND METHODS

A total of 90 female patients aged 20 to 70 years, American Society of Anesthesiologists (ASA) I to III, undergoing unilateral MRM were randomly allocated into 3 groups. All patients received postoperative morphine patient-controlled analgesia (PCA). Continuous TPVB and continuous PECs were added in group II and group III, respectively. Postoperative morphine consumption during the first 48 hours and postoperative visual analog scale were recorded.

RESULTS

The cumulative morphine consumption in the first 24 hours postoperative was higher in the PCA-M group (27.47±4.95 mg) than that of the TPVB group (8.43±2.67 mg) and PEC group (13.47±3.89 mg) (P<0.001, confidence interval: 16.6-21.5 and 11.6-16.4, respectively). It was significantly higher in the PEC group as compared with the TPVB group (P<0.001, confidence interval: 2.6-7.5). On admission to postanesthesia care unit till 2 hours postoperative, the median visual analog scale score at rest was higher in the PCA-M group than that of the TPVB group (P<0.05) and PEC group (P<0.05) without statistical difference between the TPVB group and PEC group.

DISCUSSION

Continuous PEC and continuous TPVB reduced the postoperative morphine consumptions as compared with the intravenous opioid analgesia in patients undergoing MRM with greater reduction in TPVB and without increased adverse effects.

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.

Safety of treatment options available for postoperative pain

IntroductionPostoperative pain is one of the most common adverse events after surgery and has been shown to increase the risk of other complications. On the other hand, liberal opioid use in the perioperative period is also associated with risk of adverse events. The current consensus is therefore to provide multimodal, opioid minimizing analgesia after surgery.Areas CoveredIn this review, we will discuss the benefits and risks associated with non-opioid analgesics, including non-steroidal anti-inflammatory drugs, gabapentinoids, ketamine, α-2 agonists, and corticosteroids. In addition, we will discuss the general and block-specific risks associated with regional anesthestic techniques.Expert OpinionAdverse events associated with non-opioid analgesics are rare outside their specific contraindicated patient groups, especially when dosed appropriately. α-2 agonists can cause transient hypotension and bradycardia, and gabapentinoids may cause sedation in higher risk patient populations. Regional anesthesia techniques are generally safe when done by an experienced practitioner. We therefore encourage the development of standardized multimodal analgesic protocols, which may facilitate opioid minimization and lead to better patient outcomes.

Predicting Unacceptable Pain in Cardiac Surgery Patients Receiving Morphine Maintenance and Rescue Doses: A Model-Based Pharmacokinetic-Pharmacodynamic Analysis

BACKGROUND

Optimal analgesic treatment following cardiac surgery is crucial for both patient comfort and successful postoperative recovery. While knowledge of both the pharmacokinetics and pharmacodynamics of analgesics is required to predict optimal drug dosing, models quantifying the pharmacodynamics are scarce. Here, we quantify the pharmacodynamics of morphine by modeling the need for rescue morphine to treat unacceptable pain in 118 patients after cardiac surgery.

METHODS

The rescue morphine event data were analyzed with repeated time-to-event (RTTE) modeling using NONMEM. Postoperative pain titration protocol consisted of continuous morphine infusions (median duration 20.5 hours) with paracetamol 4 times daily and rescue morphine in case of unacceptable pain (numerical rating scale ≥4).

RESULTS

Patients had a median age of 73 years (interquartile range [IQR]: 63-77) and median bodyweight of 80 kg (IQR: 72-90 kg). Most patients (55%) required at least 1 rescue morphine dose. The hazard for rescue morphine following cardiac surgery was found to be significantly influenced by time after surgery, a day/night cycle with a peak at 23:00 (95% confidence interval [CI], 19:35-02:03) each day, and an effect of morphine concentration with 50% hazard reduction at 9.3 ng·mL-1 (95% CI, 6.7-16).

CONCLUSIONS

The pharmacodynamics of morphine after cardiac surgery was successfully quantified using RTTE modeling. Future studies can be used to expand the model to better predict morphine's pharmacodynamics on the individual level and to include the pharmacodynamics of other analgesics so that improved postoperative pain treatment protocols can be developed.

Comparative study of verbal rating scale and numerical rating scale to assess postoperative pain intensity in the post anesthesia care unit: A prospective observational cohort study

ABSTRACT

Postsurgical patients usually have difficulty in answering the self-report pain scales due to the residual effects of anesthetic or sedative agents in the post-anesthesia care unit (PACU). A comparative analysis of pain assessment tools used in the PACU is lacking.In this prospective observational study, we compared the intensity of pain using the 11-point numeric rating scale (NRS) and the 4-category verbal rating scale (VRS) thrice, 5 minutes after PACU admission, 20 minutes after the first assessment, and just before discharge from the PACU in 200 patients undergone surgery. Spearman rank correlation analysis was used to investigate the correlation between 2 scales, and the weighted kappa (κ) coefficient was performed to evaluate inter-scale reliability. Response rates of the 2 scales were also compared.VRS and NRS were highly correlated during all 3 comparisons (r = 0.767, 0.714, and 0.653, respectively; P < .0001). Each category of VRS showed a statistically significant difference in pain intensity measured by NRS during all 3 assessments. Inter-scale reliability had a fair strength of agreement for all 3 measurements (weighted κ = 0.519, 95% CI: 0.421-0.618; weighted κ = 0.511, 95% C.I: 0.409-0.613; weighted κ = 0.452, 95% C.I: 0.352-0.551, respectively). VRS showed a higher response rate for PACU patients compared to NRS in all 3 measurements (96% vs 77.5%, 99% vs 81.5%, and 96.5% vs 86.5%, respectively; P < .0001).In the PACU, VRS is a reasonable and practical pain intensity measurement tool for postsurgical patients, considering the high correlation between VRS and NRS, and a higher response rate.

Predicted Versus Non-Predicted Opioid Administration Using Preoperative Pain Sensitivity in Patients Undergoing Gynecological Surgery: A Randomized-Controlled Trial

Individualized administration of opioids based on preoperative pain sensitivity may improve postoperative pain profiles. This study aimed to examine whether a predicted administration of opioids could reduce opioid-related adverse effects after gynecological surgery. Patients were randomized to the predicted group or control group. Participants received a preoperative sensory test to measure pressure pain thresholds. Patients were treated with a higher or lower (15 or 10 μg/mL) dose of fentanyl via intravenous patient-controlled analgesia. The opioid dose was determined according to pain sensitivity in the predicted group, while it was determined regardless of pain sensitivity in the control group. The primary outcome was the incidence of nausea over the first 48 h postoperative period. Secondary outcomes included postoperative pain scores and opioid requirements. There was no difference in the incidence of nausea (40.0% vs. 52.5% in predicted and control groups, respectively; p = 0.191) and postoperative pain scores (3.3 vs. 3.5 in predicted and control groups, respectively; p = 0.691). However, opioid consumptions were lower in the predicted group compared to the control group (median 406.0 vs. 526.5 μg; p = 0.042). This study showed that offering a predicted dose of opioids according to pain sensitivity did not affect the incidence of nausea and pain scores.

Postoperative cognitive dysfunction is made persistent with morphine treatment in aged rats

Postoperative cognitive dysfunction (POCD) is the collection of cognitive impairments, lasting days to months, experienced by individuals following surgery. Persistent POCD is most commonly experienced by older individuals and is associated with a greater vulnerability to developing Alzheimer's disease, but the underlying mechanisms are not known. It is known that laparotomy (exploratory abdominal surgery) in aged rats produces memory impairments for 4 days. Here we report that postsurgical treatment with morphine extends this deficit to at least 2 months while having no effects in the absence of surgery. Indeed, hippocampal-dependent long-term memory was impaired 2, 4, and 8 weeks postsurgery only in aged, morphine-treated rats. Short-term memory remained intact. Morphine is known to have analgesic effects via μ-opioid receptor activation and neuroinflammatory effects through Toll-like receptor 4 activation. Here we demonstrate that persistent memory deficits were mediated independently of the μ-opioid receptor, suggesting that they were evoked through a neuroinflammatory mechanism and unrelated to pain modulation. In support of this, aged, laparotomized, and morphine-treated rats exhibited increased gene expression of various proinflammatory markers (IL-1β, IL-6, TNFα, NLRP3, HMGB1, TLR2, and TLR4) in the hippocampus at the 2-week time point. Furthermore, central blockade of IL-1β signaling with the specific IL-1 receptor antagonist (IL-1RA), at the time of surgery, completely prevented the memory impairment. Finally, synaptophysin and PSD95 gene expression were significantly dysregulated in the hippocampus of aged, laparotomized, morphine-treated rats, suggesting that impaired synaptic structure and/or function may play a key role in this persistent deficit. This instance of long-term memory impairment following surgery closely mirrors the timeline of persistent POCD in humans and may be useful for future treatment discoveries.

Ultrasound-Guided Erector Spinae Plane Block in Patients Undergoing Laparoscopic Bariatric Surgery: A Prospective Randomized Controlled Trial

BACKGROUND

Bariatric surgery is frequently complicated with considerable postoperative pain. We evaluated the impact of ultrasound-guided erector spinae plane block on perioperative analgesia and pulmonary functions following laparoscopic bariatric surgery.

METHODS

A total of 60 patients aged 18 to 65 years with a body mass index (BMI) of ≥ 40 kg/m² were randomly allocated into two groups. Patients received either bilateral erector spinae plane block using 20 mL bupivacaine 0.25% at the level of the T7 transverse process or bilateral sham block using 20 mL normal saline on each side. Visual analog scale, intraoperative fentanyl consumption, the cumulative 24-hour postoperative morphine consumption, and postoperative pulmonary functions were recorded.

RESULTS

Visual analog scale for the first eight postoperative hours were significantly lower in the erector spinae plane block group than the control group. The median (interquartile range [IQR]) intraoperative fentanyl consumption was higher in the control group (159.5 [112.0 to 177.8] μg) than in the erector spinae plane block group (0.0 [0.0 to 74.5] μg) (P < 0.001). The median (IQR) cumulative 24-hour postoperative morphine consumption was lower in the erector spinae plane block group (8.0 [7.0 to 9.0] mg) than in the control group (21.0 [17.0 to 26.25] mg) (P < 0.001, 95% CI [11.00, 15.00]). Postoperative pulmonary functions were significantly impaired in both groups compared with baseline values without significant difference between both groups.

CONCLUSION

Ultrasound-guided erector spinae plane block provided satisfactory postoperative analgesia following laparoscopic bariatric surgery with decreased analgesic consumption without significant difference in postoperative pulmonary functions compared with the control group.

The art and science of drug titration

A “one-size-fits-all” approach has been the standard for drug dosing, in particular for agents with a wide therapeutic index. The scientific principles of drug titration, most commonly used for medications with a narrow therapeutic index, are to give the patient adequate and effective treatment, at the lowest dose possible, with the aim of minimizing unnecessary medication use and side effects. The art of drug titration involves the interplay of scientific drug titration principles with the clinical expertise of the healthcare provider, and an individualized, patient-centered partnership between the provider and the patient to review the delicate balance of perceived benefits and risks from both perspectives. Drug titration may occur as up-, down-, or cross-titration depending on whether the goal is to reach or maintain a therapeutic outcome, decrease the risk of adverse effects, or prevent withdrawal/discontinuation syndromes or recurrence of disease. Drug titration introduces additional complexities surrounding the conduct of clinical trials and real-world studies, confounding our understanding of the true effect of medications. In clinical practice, wide variations in titration schedules may exist due to a lack of evidence and consensus on titration approaches that achieve an optimal benefit-harm profile. Further, drug titration may be challenging for patients to follow, resulting in suboptimal adherence and may require increased healthcare-related visits and coordination of care amongst providers. Despite the challenges associated with drug titration, it is a personalized approach to drug dosing that blends science with art, and with supportive real-world outcomes-based evidence, can be effective for optimizing pharmacotherapeutic outcomes and improving drug safety.

Post-operative opioid-related adverse events with intravenous oxycodone compared to morphine: A randomized controlled trial

BACKGROUND

The value of intravenous oxycodone compared to morphine remains controversial. The purpose of this trial was to compare opioid-related adverse events (ORAES) of intravenous oxycodone and morphine after total hip arthroplasty.

METHODS

Patients scheduled for total hip arthroplasty were enrolled in this study of post-operative pain treatment with intravenous oxycodone or intravenous morphine (ratio 1:1). After surgery, patients received similar drug regimens for titration in the post-operative care unit followed by intravenous patient-controlled analgesia (PCA). The primary outcome was the number of patients with ≥1 ORAEs within the first 24 hours defined as either nausea, vomiting, respiratory depression, pruritus, urinary retention requiring evacuation, allergy, hallucinations. Secondary outcomes included pain scores and opioid consumption.

RESULTS

The analysis included 238 patients with similar characteristics. There were 55 patients with at least one ORAEs in the oxycodone group vs 46 in the morphine group: 48% vs 40%, P = .19; relative risk = 1.22 (0.91:1.63). Intravenous oxycodone vs intravenous morphine requirements were respectively (median, IQR): 6 (0-11) vs 8 (0-12) mg (P = .06) for titration, 15 (8-26) vs 8 (5-16) mg (P = .001) for PCA, and 22 (12-37) mg vs 19 (11-28) mg for cumulated intravenous consumption (P = .048). During the first 24 hours, there was no difference in secondary outcomes (oxycodone vs morphine, respectively, in %): nausea (15 vs 13), vomiting (5 vs 5), urinary retention (20 vs 12) or pain scores.

CONCLUSION

This study demonstrates that IV oxycodone did not significantly reduce ORAEs within the first 24 hours compared to similar ratio of IV morphine.

Characterisation of pragmatic postoperative PAin Trajectories over seven days and their association with CHronicity after 3 months: a prospective, pilot cohort study (PATCH study)

BACKGROUND

Reliable outcome measurement providing information both on early and late postoperative pain outcomes are still lacking. The purpose of this study was: 1) to characterise postoperative pain trajectories according to an innovative pragmatic concept: ideal pain trajectory (rapid and sustained pain relief) vs non-ideal pain trajectories (late, transient, or no pain relief); and 2) to assess the incidence of persistent post-surgical pain (PPSP) and the potential association between non-ideal pain trajectories and PPSP.

METHODS

This prospective observational pilot cohort study was performed from March until June 2016. A total of 344 patients undergoing major general surgery were invited to complete a self-assessment of pain intensity using numerical rating scale (NRS; 0 = no pain to 10 = worst pain) from day 1 until day 7 after surgery, in order to establish their pain trajectory. Three months after surgery, patients were screened for PPSP.

RESULTS

Rest pain score was analysed in 308 participants. Among them, 210 (68% - 95% CI: 63-73) had an "ideal" pain trajectory, while 98 (32% - 95% CI: 27-37) had "non-ideal" pain trajectories. Three months after surgery, 31% (95% CI: 26-37) reported PPSP. Multivariable analysis showed that "non-ideal" pain trajectories [OR 2.25; (95% CI: 1.26-4.01) P =  0.006] were significantly associated with PPSP.

CONCLUSIONS

The present study proposes an innovative pragmatic concept of postoperative pain trajectories: ideal vs non-ideal pain trajectories, providing information both on acute postoperative pain resolution and early identification patients at risk for developing PPSP.

TRIAL REGISTRATION

NCT02599233; November, 6, 2015, with clinicaltrials.gov.

Single dose of intraoperative intravenous morphine for analgesia in children undergoing tonsillectomy: Randomized, double-blind clinical trial

INTRODUCTION

Children undergoing tonsillectomy have severe pain in the postoperative period. One of the pharmacological options for analgesia is opioids, such as morphine. However, the risks of adverse effects, such as increased recovery time from anesthesia and respiratory depression, can limit its use.

OBJECTIVES

To evaluate the use of intraoperative intravenous morphine to reduce immediate postoperative pain in children undergoing tonsillectomy.

METHODS

In this double-blind randomized study, children aged 3-10 years were submitted to tonsillectomy, with or without adenoidectomy, and divided into two groups. Children in group M received 0.1 mg/kg of intravenous morphine during anesthetic induction, while those in the control group received conventional anesthesia without morphine. Postoperative pain perceptions were assessed at 30, 60, 120, 180 and 240 min after recovery from anesthesia, by the children themselves and also by their parents or guardians, using a facial pain scale.

RESULTS

A total of 57 children were included, 30 in the group with morphine and 27 in the group without morphine. According to the children themselves, the postoperative pain was less at the evaluations performed at 30 min after awakening from anesthesia (p =  0.023), while according to their parents/guardians, the pain was less intense in the evaluations performed at 30 (p =  0.002), 60 (p =  0.006) and 180 min (p =  0.007) after awakening. Moreover, postoperative analgesics were less requested by children in the morphine group. No observed side effects were associated with the use of morphine.

CONCLUSION

A single dose of intravenous morphine during anesthetic induction reduced the intensity of immediate postoperative pain in children undergoing tonsillectomy, without increasing the time of awakening from anesthesia and with lower consumption of rescue analgesics.

Ultrasound-guided Modified Parasternal Intercostal Nerve Block: Role of Preemptive Analgesic Adjunct for Mitigating Poststernotomy Pain

Background and Aim

To assess the quality and effectiveness of postoperative pain relief after fast-tracking tracheal extubation in cardiac surgery intensive care unit, effected by a single-shot modified parasternal intercostal nerve block compared with routine in-hospital analgesic protocol, when administered before sternotomy.

Design

A prospective, randomized, double-blinded interventional study.

Setting

Single-center tertiary teaching hospital.

Participants

Ninety adult patients undergoing elective coronary artery bypass grafting surgery under cardiopulmonary bypass.

Materials and Methods

Patients were randomized into two groups. Patients in the parasternal intercostal block group (PIB) (n = 45) received ultrasound-guided modified parasternal intercostal nerve block with 0.5% levobupivacaine after anesthesia induction at 2^nd-6^th intercostal space along postinduction using standardized anesthesia drugs with routine postoperative hospital analgesic protocol with intravenous morphine. Patients in the group following routine hospital analgesia protocol (HAP) (n = 45) served as controls, with standardized anesthesia drugs and routine hospital postoperative analgesic protocol with intravenous morphine. The primary study outcome aimed to evaluate pain at rest and when doing deep breathing exercises with spirometry, coughing expectorations using a 11-point numerical rating scale.

Results

The postoperative pain score at rest and during breathing exercises was compared between the two groups at different time durations (15 min after extubation and every 4^th hourly for 24 h). Patients in the PIB group had significantly lower pain scores and better quality of analgesia during the entire study period at rest and during breathing exercise (P < 0.0001). Furthermore, the side effect profile and need of rescue analgesics were better in the PIB group than the HAP group at different time intervals.

Conclusion

PIB is safe for presternotomy administration and provided significant quality of pain relief postoperatively, as seen after tracheal extubation for a period of 24 h, on rest as well as with deep breathing, coughing, and chest physiotherapy exercises when compared to intravenous morphine alone after sternotomy. This study further emphasizes the role of preemptive analgesia in mitigating postoperative sternotomy pain and it's role as a plausible safe analgesic adjunct facilitating fast tracking with sternotomies on systemic heparinization.

Foreseeing postoperative pain in neurosurgical patients: pupillometry predicts postoperative pain ratings-an observational study

Pupillary reflex dilation (PRD) is triggered by noxious stimuli and diminished by opioid administration. In the postoperative period, PRD has been shown to be correlated with pain reporting and a useful tool to guide opioid administration. In this study we assessed whether pupillary measurements taken before extubation were related with the patient's reported pain in the Post-Anesthesia Care Unit (PACU) using the Numerical Rating Scale (NRS). Our objective was to evaluate the correlation of PRD and pupillary variables measured intraoperatively with postoperative pain under the same opioid concentration. This was a prospective observational study of 26 neurosurgical patients undergoing general anesthesia exclusively with propofol and remifentanil. A portable infrared pupillometer was used to provide an objective measure of pupil size and PRD (using the Pupillary Pain Index) before extubation. Pain ratings were obtained from patients after recovery of consciousness, while remifentanil was maintained at 2 ng/mL. A significant correlation was observed between NRS scores and pre-extubation PPI (r_S = 0.62; P = 0.002), as well as between NRS scores and pupil diameter before tetanic stimulation PPI (r_S = 0.56, P = 0.006). We also found a negative correlation between pupil diameter and age (r_S = - 0.42, P = 0.04). The statistically significant correlation between pre-extubation PPI scores and NRS scores, as well as between the pupillary diameter before tetanic stimulation and NRS scores suggest the possibility of titrating analgesia at the end of the intraoperative period based on individual responses. This could allow clinicians to identify the ideal remifentanil concentration for the postoperative period.

Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after hysteroscopy: a randomized controlled study

OBJECTIVE

To compare the time spent in the Post-Anesthesia Care Unit (PACU) and the pain-relieving effects of treatment with high-frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) opioids after hysteroscopy.

METHODS

All patients who postoperatively reported a visual analogue scale (VAS) pain score of ≥3 were included in the study. TENS treatment was given with a stimulus intensity between 40 and 60 mA for 1 minute and repeated once if there was insufficient pain relief. In the opioid group, a fractionated dose of 5 mg morphine was administered. If the patient reported insufficient pain relief after the assigned treatment, the patient was reassigned to the other treatment group.

RESULTS

Seventy-four women were randomized to TENS (n=38) or IV opioids (n=36) for treatment. Both groups reported significant pain relief after discharge from the PACU, with a decrease of VAS scores from 5.6 to 1.4 in the TENS group (P<0.001) and 5.1 to 1.3 in the opioid group (P<0.001). There were no significant differences between the groups. When only the responders in both groups, i.e., patients with VAS scores of <3 on respectively assigned treatments, were compared, the TENS responders (n=22) were found to have spent a significantly shorter time in the PACU (91 vs. 69 minutes, P=0.013) compared to the opioid responders (n=20).

CONCLUSION

Using TENS as first line of pain relief may reduce the need for postoperative opioids. In addition, TENS appears preferable as the first line of treatment due to its association with a shorter time spent in the PACU if the patient responds to the treatment.

TRIAL REGISTRATION

Västra Götalandsregionen Identifier: 211261.

A Scoping Review of Intravenous Opioid Pain Protocols and Their Dose-Time Intervals in the Management of Acute Postoperative Pain in the Postanesthesia Care Unit

PURPOSE

This review aims to explore intravenous opioid pain protocols and their dose-time intervals in managing acute postoperative pain in adults in the postanesthesia care unit (PACU).

DESIGN

A scoping review using a systematic search strategy.

METHODS

Sixteen articles were identified from MEDLINE, CINAHL, PubMed, Embase, and Cochrane specific to the aims.

FINDINGS

The literature demonstrated several variations on dose-time intervals used for opioid pain protocol administration globally. Furthermore, opioid analgesic pain protocols in the PACU appear to be effective in postoperative pain management. However, the literature did not identify optimal time intervals related to dose administration within these protocols.

CONCLUSIONS

Literature gaps were identified regarding the significance of dose-time intervals when using opioid analgesic pain protocols in the PACU.

Fascia iliaca compartment block as a preoperative analgesic in elderly patients with hip fractures - effects on cognition

BACKGROUND

Impaired cognition is a major risk factor for perioperative delirium. It is essential to provide good pain control in patients with hip fractures and especially important in patients with severely impaired cognitive status, as they receive less pain medication, have poorer mobility, poorer quality of life and higher mortality than patients with intact cognition. The purpose of this study was to examine the association between preoperative pain management with nerve blocks and cognitive status in patients with hip fractures during the perioperative period.

METHODS

One hundred and twenty-seven patients with hip fractures participating in a double-blind, randomised, controlled trial were included in this study. At hospital admission, a low-dose fascia iliaca compartment block (FICB) was administered as a supplement to regular analgesia. Cognitive status was registered on arrival at hospital before FICB and on the first postoperative day using the Short Portable Mental Status Questionnaire.

RESULTS

Changes in cognitive status from arrival at hospital to the first postoperative day showed a positive, albeit not significant, trend in favour of the intervention group. The results also showed that patients with no or a moderate cognitive impairment received 50% more prehospital pain medication than patients with a severe cognitive impairment. FICB was well tolerated in patients with hip fractures.

CONCLUSION

Fascia iliaca compartment block given to patients with hip fractures did not affect cognitive status in this study. Patients with a cognitive impairment may receive inadequate pain relief after hip fracture and this discrimination needs to be addressed in further studies.

TRIAL REGISTRATION

EudraCT number 2008-004303-59 date of registration: 2008-10-24.

Opioid-related genetic polymorphisms do not influence postoperative opioid requirement: A prospective observational study

BACKGROUND

Among the various factors that may influence the pharmacological response to opioids, genetic polymorphisms [single nucleotide polymorphisms (SNP)] have generated some interest.

OBJECTIVES

To examine the influence on morphine dose requirements and adverse events in the postoperative period of four SNP [opioid receptor mu1 (OPRM1), ATP-binding cassette subfamily B, member 1 (ABCB1) ex-21 and ex-26, catechol-o-methyltransferase (COMT)] in candidate genes involved in morphine pharmacodynamics and pharmacokinetics.

DESIGN

A single centre prospective study.

SETTING

University Hospital, Paris, France, from 2 January 2007 to 15 November 2011.

PATIENTS

A total of 438 white adults scheduled for major orthopaedic surgery (spine, hip and knee) under general anaesthesia. The main exclusion criteria were receiving opioids for chronic pain, nonopioid drugs within 2 days prior to surgery, pregnancy, renal insufficiency, sleep apnoea obstruction syndrome, morbid obesity, severe hepatic impairment, cognitive dysfunction.

INTERVENTIONS

Assays of plasma concentrations of morphine and metabolites (morphine 3-glucuronide and morphine 6-glucuronide) were performed and common polymorphisms in four candidate genes [OPRM1 A118G rs1799971; P-glycoprotein (ABCB1) T3435C (rs1045642) and G2677T/A (rs2032582); COMT Val 158 Met (rs4680)] were analysed.Morphine was titrated by staff in the postanaesthesia care unit (PACU) and in the ward patient-controlled intravenous analgesia was used for 24 h.

MAIN OUTCOME MEASURES

The dose of morphine required to achieve pain relief and the influence of SNP in genes involved in morphine pharmacodynamics and kinetics on morphine dose requirements. Secondary endpoints were the concentrations of morphine, morphine 6-glucuronide and morphine 3-gluguronide, the proportion of patients requiring a rescue analgesic and the proportion of morphine-related adverse events.

RESULTS

A total of 404 patients completed the study to final analysis. The mean ± SD morphine dose to achieve pain relief was 15.8 ± 8.8 mg in the PACU and 22.7 ± 18.6 mg during patient-controlled intravenous administration. Morphine-related adverse events were observed in 37%. There was no relationship between any genetic polymorphisms and morphine dose, morphine 3-gluguronide and morphine 6-glucuronide concentration, morphine-related adverse events or pain level. In the PACU only, P-glycoprotein polymorphisms (ex-21; ex-26) were significantly associated with morphine concentration but the prediction of the model was poor (R = 0.04) CONCLUSION: No major relationship has been demonstrated between SNP of OPRM1, ABCB1, COMT and morphine requirement, pain level or adverse effects in the postoperative period.

TRIAL REGISTRATION

NCT00822549 (www.clinicaltrials.gov).

Intravenous Oxycodone Versus Other Intravenous Strong Opioids for Acute Postoperative Pain Control: A Systematic Review of Randomized Controlled Trials

Introduction

Optimal pain management is crucial to the postoperative recovery process. We aimed to evaluate the efficacy and safety of intravenous oxycodone with intravenous fentanyl, morphine, sufentanil, pethidine, and hydromorphone for acute postoperative pain.

Methods

A systematic literature search of PubMed, Cochrane Library, and EMBASE databases was performed for randomized controlled trials published from 2008 through 2017 (inclusive) that evaluated the acute postoperative analgesic efficacy of intravenous oxycodone against fentanyl, morphine, sufentanil, pethidine, and hydromorphone in adult patients (age ≥ 18 years). Outcomes examined included analgesic consumption, pain intensity levels, side effects, and patient satisfaction.

Results

Eleven studies were included in the review; six compared oxycodone with fentanyl, two compared oxycodone with morphine, and three compared oxycodone with sufentanil. There were no eligible studies comparing oxycodone with pethidine or hydromorphone. Overall, analgesic consumption was lower with oxycodone than with fentanyl or sufentanil. Oxycodone exhibited better analgesic efficacy than fentanyl and sufentanil, and comparable analgesic efficacy to morphine. In terms of safety, there was a tendency towards more side effects with oxycodone than with fentanyl, but the incidence of side effects with oxycodone was comparable to morphine and sufentanil. Where patient satisfaction was evaluated, higher satisfaction levels were observed with oxycodone than with sufentanil and comparable satisfaction was noted when comparing oxycodone with fentanyl. Patient satisfaction was not evaluated in the studies comparing oxycodone with morphine.

Conclusions

Our findings suggest that intravenous oxycodone provides better analgesic efficacy than fentanyl and sufentanil, and comparable efficacy to morphine with less adverse events such as sedation. No studies comparing intravenous oxycodone with pethidine or hydromorphone were identified in this review. Better alignment of study methodologies for future research in this area is recommended to provide the best evidence base for a meta-analysis.

Funding

Mundipharma Singapore Holding Pte Ltd, Singapore.

Electronic supplementary material

The online version of this article (10.1007/s40122-019-0122-4) contains supplementary material, which is available to authorized users.

Comparison of Ultrasound-Guided Subcostal Transversus Abdominis Plane Block and Quadratus Lumborum Block in Laparoscopic Cholecystectomy: A Prospective, Randomized, Controlled Clinical Study

Background

The aim of this study was to compare the effectiveness of ultrasound-guided (USG) subcostal transversus abdominis plane (TAP) block and quadratus lumborum (QL) block as preventive analgesia methods after laparoscopic cholecystectomy.

Methods

A total of 120 patients, 18-75 years of age, were separated into 2 groups preoperatively. Patients in group TAP (n = 60) received 0.3 ml/kg bupivacaine with USG bilateral subcostal TAP block; patients in group QL (n = 60) received 0.3 ml/kg bupivacaine with USG bilateral QL block. Patients were assessed 24 h postoperatively, and pain scores, time to first analgesia requirement, total analgesia dose, and postoperative complications during the first 24 h were recorded.

Results

Fifty-three patients in group TAP and 54 in group QL were ultimately evaluated. No statistically significant difference was found in at rest and dynamic visual analog scale scores between the groups. There was also no statistically significant difference between the groups with regard to total analgesia consumption. Although the duration of anesthesia was significantly longer in group QL, no statistically significant difference was found in the duration of surgery between the groups (p < 0.05).

Conclusions

Results of this study demonstrated that USG subcostal TAP and QL blocks similarly reduced postoperative pain scores and analgesia consumption, with high patient satisfaction. However, subcostal TAP block could be considered preferable to QL block because it can be applied easily and in a shorter time.

Evaluation of the perfusion index according to the visual analog scale in postoperative patients

Objectives:

To evaluate the possible value of the perfusion index (PI) as a tool for pain assessment.

Methods:

This prospective, observational study was performed with 89 patients underwent surgery with general anesthesia. The patients with visual analog scale (VAS)>3 were grouped as M1, and patients with VAS≤3 and performed morphine were grouped as M2. After surgery patients with VAS>3 were given 2mg morphine. Patients with VAS>3 were given increments of intravenous morphine (2 mg) at 20 minute intervals until VAS<3. The correlation and difference between PI and VAS score values were evaluated before and after analgesic administration.

Results:

Significant changes were found in both PI values and VAS scores between M1 and M2 groups (2.80±0.77, 3.97±0.94, p<0.001; 6.60±1.20, 2.74±0.46, p<0.001) Despite no correlation was found between PI values and VAS scores of M1 and M2 groups, weak negative correlation was detected between differences in PI values and VAS scores among groups (r=-0.255, p=0.016).

Conclusion:

Perfusion index is a parameter that can be used in the assessment of postoperative pain and responses to analgesics.

Effects of NOP-Related Ligands in Nonhuman Primates

The nociceptin/orphanin FQ peptide (NOP) receptor-related ligands have been demonstrated in preclinical studies for several therapeutic applications. This article highlights (1) how nonhuman primates (NHP) were used to facilitate the development and application of positron emission tomography tracers in humans; (2) effects of an endogenous NOP ligand, nociceptin/orphanin FQ, and its interaction with mu opioid peptide (MOP) receptor agonists; and (3) promising functional profiles of NOP-related agonists in NHP as analgesics and treatment for substance use disorders. NHP models offer the most phylogenetically appropriate evaluation of opioid and non-opioid receptor functions and drug effects. Based on preclinical and clinical data of ligands with mixed NOP/MOP receptor agonist activity, several factors including their intrinsic efficacies for activating NOP versus MOP receptors and different study endpoints in NHP could contribute to different pharmacological profiles. Ample evidence from NHP studies indicates that bifunctional NOP/MOP receptor agonists have opened an exciting avenue for developing safe, effective medications with fewer side effects for treating pain and drug addiction. In particular, bifunctional NOP/MOP partial agonists hold a great potential as (1) effective spinal analgesics without itch side effects; (2) safe, nonaddictive analgesics without opioid side effects such as respiratory depression; and (3) effective medications for substance use disorders.

Satisfactory Analgesia with Minimal Emesis in Day Surgeries (SAME DayS): a protocol for a randomised controlled trial of morphine versus hydromorphone

INTRODUCTION

There has been an exponential increase in the number of ambulatory surgeries (AS). Pain and postoperative nausea vomiting (PONV) affects the recovery, discharge and overall satisfaction of patients having AS. Opioids remain the primary modality for moderate to severe pain. Since there is no perfect opioid, physicians should ideally use the opioid that optimally balances benefits and risks. Present decisions on the choice between morphine (M) and hydromorphone (HM) are based on individual experience and observation. Our primary objective is to compare the proportion of patients having AS achieving satisfactory analgesia without significant PONV when using M compared with HM. Secondarily we will compare the proportion of patients with adverse events, analgesic used, patient satisfaction, time to discharge and postdischarge symptoms.

METHODS AND ANALYSIS

This is a two-arm, multicentre, parallel group, randomised controlled trial of 400 patients having AS. Eligible patients undergoing AS of the abdominal and pelvic regions with a potential to cause moderate to severe pain will be recruited in the preoperative clinic. Using a computer-generated randomization, with a 1:1 allocation ratio, patients will be randomised to M or HM. Patients, healthcare providers and research personnel will be blinded. Study interventions will be administered in the recovery using equianalgesic doses of M or HM in concealed syringes. Patients will be followed in hospital and up to 3 months. Intention-to-treat approach will be used for analysis.

ETHICS AND DISSEMINATION

This study has been approved by the Hamilton integrated research ethics board. We plan to publish our trial findings and present our findings at scientific meetings.

TRAIL REGISTRATION NUMBER

NCT02223377; Pre-results.

Postoperative pain management in children: Guidance from the pain committee of the European Society for Paediatric Anaesthesiology (ESPA Pain Management Ladder Initiative)

The main remit of the European Society for Paediatric Anaesthesiology (ESPA) Pain Committee is to improve the quality of pain management in children. The ESPA Pain Management Ladder is a clinical practice advisory based upon expert consensus to help to ensure a basic standard of perioperative pain management for all children. Further steps are suggested to improve pain management once a basic standard has been achieved. The guidance is grouped by the type of surgical procedure and layered to suggest basic, intermediate, and advanced pain management methods. The committee members are aware that there are marked differences in financial and personal resources in different institutions and countries and also considerable variations in the availability of analgesic drugs across Europe. We recommend that the guidance should be used as a framework to guide best practice.

An observational study: The utility of perfusion index as a discharge criterion for pain assessment in the postanesthesia care unit

Acute post-operative pain can remain untreated if patients cannot express themselves. The perfusion index (PI) may decrease when pain activates sympathetic tone and may increase after analgesics are administered. We evaluated if the perfusion index is a feasible indicator for objectively assessing pain relief in the postanesthesia care unit (PACU) and calculated the changes in PI measurements at the time of discharge from the PACU relative to baseline PI measurements to examine if the PI is a useful criterion for discharging patients from the postanesthesia care unit. This retrospective observational study enrolled female patients who were admitted for gynecological or general surgery. The patients received general anesthesia and were admitted to the postanesthesia care unit. The PI, visual analogue scale (VAS) score, heart rate, and blood pressure were recorded before and after administration of intravenous morphine. Changes in these parameters before and after analgesics were administered and the difference of these parameters between age and BMI subgroups were compared. The correlation between the PI and VAS score, ΔPI and ΔVAS, and %ΔPI and %ΔVAS were also evaluated. The percentage change in ΔPI (P9-T0/T0) of the patients at the time of discharge from the postanesthesia care unit relative to baseline PI measurements was calculated. Eighty patients were enrolled, and there were 123 instances during which analgesia was required. Heart rate, PI, and VAS score were significantly different before and after analgesics were administered (p < 0.0001). The difference of parameters between age and BMI subgroups were not significant. The correlation between the PI and VAS score, ΔPI and ΔVAS, and the percentage change in ΔPI and ΔVAS showed weak correlations in age, BMI subgroups, and all measurements. The baseline PI and the PI when arriving at and when being discharged from the postanesthesia care unit were significantly different (p < 0.01). The mean percentage change in Δ PI at the time of discharge from the PACU was 66.2%, and the 99% confidence interval was 12.2%~120.3%. The perfusion index was increased, and the VAS score was decreased significantly after analgesics were administered, but the correlation was weak in each subgroup. The VAS score is a subjective and psychometric parameter. The PI increased when partial pain relief was achieved after morphine was administered but did not reflect pain intensity or changes in the VAS score regardless of age or BMI. A percentage change in ΔPI at the time of discharge from the PACU relative to baseline PI measurements of greater than 12% can be used as a supplemental objective discharge criterion for pain assessment in the postanesthesia care unit.

Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after gynecologic laparoscopic surgery: a randomized controlled study

Background

The aim of the study was to compare the pain relieving effect and the time spent in the recovery unit after treatment with high frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) opioids after gynecologic laparoscopic surgery.

Methods

All patients who postoperatively reported visual analogue scale (VAS) pain score ≥ 3 were consecutively included in the study. The TENS treatment was given with a stimulus intensity between 40–60 mA during 1 minute, repeated once if insufficient pain relief. In the opioid group, a maximum dose of 10 mg morphine was given IV. If the patient reported insufficient pain relief (VAS ≥ 3) on the assigned treatment, the patient crossed over to the other treatment group.

Results

Ninety-three women were randomized to TENS (n = 47) or IV opioids (n = 46). Both groups reported significant pain relief at leave from the recovery unit (TENS group: VAS 5.4 to 1.0, P < 0.001; IV opioid group: VAS 5.2 to 1.1, P < 0.001) with no differences between the groups. When only responders, i.e. patients with VAS < 3 after assigned treatment, were compared the TENS responders spent significantly shorter time in the recovery unit (90 vs. 122 minutes, P = 0.008) compared to the responders in the opioid group.

Conclusions

TENS and IV opioids are both effective treatments for pain relief after gynecologic laparoscopic surgery. TENS seems to be preferable for first choice of treatment as the treatment is associated with shorter time spent in recovery unit if the patient responds to the treatment.

Evidence-based guidelines for supportive care of patients with Ebola virus disease

The 2013-16 Ebola virus disease outbreak in west Africa was associated with unprecedented challenges in the provision of care to patients with Ebola virus disease, including absence of pre-existing isolation and treatment facilities, patients' reluctance to present for medical care, and limitations in the provision of supportive medical care. Case fatality rates in west Africa were initially greater than 70%, but decreased with improvements in supportive care. To inform optimal care in a future outbreak of Ebola virus disease, we employed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology to develop evidence-based guidelines for the delivery of supportive care to patients admitted to Ebola treatment units. Key recommendations include administration of oral and, as necessary, intravenous hydration; systematic monitoring of vital signs and volume status; availability of key biochemical testing; adequate staffing ratios; and availability of analgesics, including opioids, for pain relief.