A Dose-Finding Study of Dexketoprofen in Patients Undergoing Laparoscopic Cholecystectomy: A Randomized Clinical Trial on Effects on the Analgesic Concentration of Oxycodone

Application of oxycodone in anesthesia induction and overall management of Da Vinci robot-assisted nephrectomy: A randomized controlled trial

BACKGROUND

This study aimed to evaluate the application of oxycodone in anesthesia induction and overall management of Da Vinci robot-assisted nephrectomy.

METHODS

A total of 42 patients undergoing Da Vinci robot-assisted nephrectomy with general anesthesia were selected. They were randomly divided into 2 groups: patients were induced with oxycodone (oxycodone group) and were induced with sufentanil (sufentanil group). The vital signs at the following time points were recorded: after injection of induced drugs (T1), during glottis exposure (T2), immediately after intubation (T3), 1 minute (T4), 2 minute (T5), 3 minute (T6), 5 minute (T7), 10 minute (T8) after intubation, during skin incision (T9), at the end of suturing skin (T10), during extubation (T11), and during hemodynamic fluctuations intraoperatively (T`). Numerical rating scale, facial affective scale and monitoring of adverse events (visual analogue scale, NVAS) were evaluated postoperatively at 1 hour (T'"1), 3 hours (T""2), 6 hours (T""3), 12 hours (T""4), 24 hours (T""5), and 48 hours (T"'6).

RESULTS

The systolic blood pressure, the diastolic blood pressure and the mean arterial blood pressure showed no statistically different changes between the 2 groups. There were no statistical differences in heart rate and respiratory rate among various timepoints intraoperatively. There were statistical differences in Bispectral index (BIS) scores in T6 between the 2 groups. The numerical rating scale and facial affective scale scores were significantly lower in oxycodone group. Anesthetized with oxycodone, the pain did not affect the sleep of patients after operation. Also, the postoperative QoR-40 scores were lower in oxycodone group.

CONCLUSION

Compared with sufentanil, anesthesia induction with 0.3 mg/kg oxycodone in Da Vinci robot-assisted nephrectomy can achieve mild pain and mild adverse responses in patients postoperatively.

The comparison of dexketoprofen and other painkilling medications (review from 2018 to 2021)

Dexketoprofen is an enantiomer of ketoprofen (S+) that belongs to nonsteroidal anti-inflammatory drugs and has analgesic, anti-inflammatory, and antipyretic properties. Dexketoprofen has a stronger effect than ketoprofen, which makes it a readily used preparation. The review aims to find in recent original publications data about dexketoprofen and its comparison with other painkilling medications. The systematic literature review was conducted in November 2021 (2018 onwards). We selected 12 articles from PubMed, Google Scholar, Medline Complete databases. In the last 4 years, there have been many publications that shed a new light on dexketoprofen. The article is a comparative analysis of dexketoprofen's action vs other nonsteroidal anti-inflammatory drugs and the combination of dexketoprofen with tramadol vs paracetamol with tramadol. The findings of the review confirm that dexketoprofen is a very good pain reliever more potent than paracetamol. Dexketoprofen produces similar effects to lidocaine and dexmedetomidine. Complex preparations containing dexketoprofen and tramadol are very effective painkilling tandem and are more effective than tramadol and paracetamol therapy in the treatment of acute pain.

New Studies on Dexketoprofen

Introduction. Dexketoprofen(DEX) belongs to nonsteroidal anti-inflammatory drugs (NSAIDs) and has analgesic, anti-inflammatory, and antipyretic properties. DEX is an enantiomer of ketoprofen (S+) and has a stronger effect than ketoprofen. It is highly effective even after the administration of small doses. The therapy with DEX does not cause serious side effects and is additionally tolerated by the body.

Aim. The review aimed to find original scientific publications on DEX in recent years and its therapeutic efficacy, safety, and tolerability.

Method. A systematic review of scientific articles published no earlier than 2015 was carried out. Materials from the PubMed, Google Scholar, and Medline Complete databases were used. The literature review was carried out in November 2021. Among the publications found, 28 scientific articles were selected for analysis.

Results and discussion. Over the recent years, there have been many publications about DEX. Articles describing new data on DEX in the treatment of pain were analyzed, compared with other drugs and mesotherapy, the latest reports of its combination with tramadol and thiocolchicoside were reviewed, and a new slow release form of DEX and new therapeutic applications of this drug were investigated. After analyzing all the studies, it was found that DEX produced similar or more effective analgesia compared to other drugs and reduced the need for emergency medications. In addition, it was noted that using DEX in combination therapy was far better than taking it alone, and was also found to be effective in raising the epileptic threshold. Mesotherapy achieved higher results in the treatment of pain symptoms compared to DEX. The side effects that appeared as a result of the use of DEX therapy were not life-threatening.

Conclusion. The results of the review confirm that DEX is a very good analgesic, which is more potent than paracetamol and diclofenac sodium while having similar effects to dexmedetomidine and lidocaine. DEX in combination with tramadol or thiocolchicoside is more effective than when the two drugs are used alone. Scientists are working on the long-acting DEX and are looking for new applications of the drug in epilepsy and oncology.

Oxycodone concentrations in the central nervous system and cerebrospinal fluid after epidural administration to the pregnant ewe

The main sites of the analgesic action of oxycodone are the brain and spinal cord. The present study describes the concentrations of oxycodone and its metabolites in the brain and spinal cord after epidural administration to the ewe. Twenty pregnant ewes undergoing laparotomy were randomized into two groups to receive epidural oxycodone: infusion group (n = 10, 0.1 mg·kg^-1 bolus followed by continuous infusion of 0.05 mg·kg^-1 ·h^-1 for five days) or repeated boluses group (n = 10, 0.2 + 2x0.1 mg·kg^-1 bolus followed by a 0.2 mg·kg^-1 bolus every 12 hours for five days). After five days of oxycodone administration, arterial blood samples were collected, the sheep were killed, and a CSF sample and tissue samples from the cortex, thalamus, cerebellum and spinal cord were obtained for the quantification of oxycodone and its main metabolites. The median plasma and CSF concentrations of oxycodone were 9.0 and 14.2 ng·mL^-1 after infusion and 0.4 and 1.1 ng·mL^-1 after repeated boluses. In the infusion group, the cortex, thalamus and cerebellum oxycodone concentrations were 4-8 times higher and in the spinal cord 1310 times higher than in plasma. In the repeated boluses group, brain tissue concentrations were similar in the three areas, and in the spinal cord were 720 times higher than in plasma. Oxymorphone was the main metabolite detected, which accumulated in the brain and spinal cord tissue. In conclusion, first, accumulation of oxycodone and oxymorphone in the CNS was observed, and second, high spinal cord concentrations suggest that epidural oxycodone may provide segmental analgesia.

Perioperative factors that contribute to postoperative pain and/or nausea and vomiting in ambulatory laparoscopic surgery

INTRODUCTION

Both postoperative pain and postoperative nausea and vomiting are major factors that determine the time and quality of recovery in laparoscopic surgery.

OBJECTIVE

To determine the perioperative factors that contribute to the appearance of postoperative pain and postoperative nausea and vomiting in outpatient laparoscopic surgery.

MATERIAL AND METHODS

A prospective study was conducted on a cohort of 297 patients undergoing laparoscopic ambulatory surgery. A record was made of preoperative factors (usual medication, anaesthetic risk, etc.), intraoperative (surgical and anaesthetic times, drugs, CO₂ pressure, etc.), and postoperative factors (major and minor complications, recovery times, etc.). As dependent variables, the postoperative symptoms considered were, nausea, vomiting, and/or postoperative pain.

RESULTS

Considering as a combined variable the occurrence of níusea, vomiting or moderate/severe pain (4 or more points on a visual analogue scale), one or more of these symptoms occurred in 58.7% of the patients (95% CI: 52.8-64.4). Using a logistic regression, the variables associated with the appearance of symptoms were: female gender (OR: 3.4), waiting time over 45minutes prior to surgery (OR: 4.9) and no anti-emetic prophylaxis (OR: 12.2).

CONCLUSIONS

In patients undergoing ambulatory laparoscopic surgery, one in 4had postoperative nausea and vomiting, and approximately half of moderate-intensity pain before discharge. Considering the overall the occurrence of pain and/or postoperative níusea and vomiting, these symptoms affect more than half of the patients being operated on, and are more frequent in women and in those who have to wait to access the operating room.

Oxycodone ameliorates the inflammatory response induced by lipopolysaccharide in primary microglia

Background

Activation of microglia participates in a wide range of pathophysiological processes in the central nervous system. Some studies reported that oxycodone (6-deoxy-7,8-dehydro-14-hydroxy-3-O-methyl-6oxomorphine) could inhibit the overactivation of glial cells in rats’ spinal cords. In the present study, we observed the effect of oxycodone on inflammatory molecules and pathway in lipopolysaccharide (LPS)-stimulated primary microglia in rats.

Materials and methods

Neonatal rats’ primary microglia were exposed to various concentrations (25, 50, 100 ng/mL) of oxycodone for 1 h after LPS stimulation for 24 h. The levels of pro-inflammatory mediators, IL-1β, TNF-α, and TGF-β1/smad2/3 signaling pathway were measured. The activation situation of microglia and the expression of TβR1 were observed by immunofluorescence.

Results

Oxycodone at 25 ng/mL did not change the levels of proinflammatory molecules and TGF-β1/smad2/3 signaling pathway in primary microglia, which was increased by LPS. Oxycodone at 50 and 100 ng/mL could significantly suppress LPS-induced production of TNF-α and IL-1β and the expression of TNF-αmRNA, IL-1βmRNA, and TGF-β1/smad2/3 signaling pathway.

Conclusion

These findings indicate that oxycodone, at relatively high clinically relevant concentration, can inhibit inflammatory response in LPS-induced primary microglia. The detailed mechanism needs to be investigated in future.

A prospective, randomized, open label, controlled study investigating the efficiency and safety of 3 different methods of rectus sheath block analgesia following midline laparotomy

BACKGROUND

There is a controversy regarding the efficacy of rectus sheath block (RSB). The aim of the present study was to evaluate analgesic efficacy and safety of three different methods of RSB in postoperative pain management after midline laparotomy.

METHODS

A prospective, randomized, controlled, open-label clinical trial with 4 parallel groups was conducted in a tertiary care hospital in Finland. A total of 57 patients undergoing midline laparotomy were randomized to the control group (n = 12) or to 1 of the 3 active RSB analgesia groups: single-dose (n = 16), repeated-doses (n = 12), or continuous infusion (n = 17). Opioid consumption with iv-patient-controlled analgesia pump was recorded, and pain scores and patients' satisfaction were surveyed on an 11-point numeric rating scale for the first 48 postoperative h. Plasma concentrations of oxycodone and levobupivacaine were analyzed. All adverse events during the hospital stay were recorded.

RESULTS

Oxycodone consumption was less during the first 12 h in the repeated-doses and in the continuous infusion groups (P = .07) and in numerical values up to 48 h in the repeated-doses group. Plasma oxycodone concentrations were similar in all 4 groups. Pain scores were lower in the repeated-doses group when coughing during the first 4 h (P = .048 vs. control group), and at rest on the first postoperative morning (P = .034 vs. the other 3 groups) and at 24 h (P = .006 vs. the single-dose group). All plasma concentrations of levobupivacaine were safe. The patients' satisfaction was better in the repeated-doses group compared with the control group (P = .025). No serious or unexpected adverse events were reported.

CONCLUSIONS

RSB analgesia with repeated-doses seems to have opioid sparing efficacy, and it may enhance pain relief and patients' satisfaction after midline laparotomy.

Analgesic Plasma Concentrations of Oxycodone After Surgery for Breast Cancer-Which Factors Matter?

We investigated factors affecting analgesic oxycodone concentrations after breast cancer surgery in 1,000 women. Preoperatively, we studied heat and cold pain sensitivities and anxiety scores. Postoperatively, rest and motion pain intensities were measured and intravenous oxycodone was administered until satisfactory analgesia. At this point, the mean oxycodone concentration (variation coefficient) was 33.3 ng/mL (66%) and it was 21.7 ng/mL (69%) when the patient requested oxycodone again. At both time points, the concentrations varied >100-fold between individuals. The analgesic oxycodone concentration was increased by 21.3% per motion pain intensity score on a 0-10 scale and by 22.3% if axillary clearance was performed instead of sentinel node biopsy (P < 0.001). Forty-seven women who were older and less anxious than others (P < 0.01) required no oxycodone. Anxiety, age, chronic pain, or preoperative pain sensitivity were not independently associated with the analgesic oxycodone concentration. CYP2D6 and CYP3A genotypes did not affect analgesic concentration or duration of analgesia.

Sufentanil sublingual formulation for the treatment of acute, moderate to severe postoperative pain in adult patients

INTRODUCTION

Sufentanil is a highly selective µ-opioid agonist commonly used by intravenous and intrathecal routes for acute pain. Sublingual sufentanil formulation for patient controlled analgesia (PCA) uses an innovative administration device that suspends a 15 µg nanotablet with a fixed lockout interval. The system is a non-invasive, less burdensome method of opioid delivery compared to intravenous and intrathecal routes. Sublingual nanotablet PCA transmucosal bioavailability is 59% and the meaningful analgesic onset time is 60 minutes. Areas covered: This paper focuses on the effectiveness, safety and feasibility of sufentanil PCA sublingual formulation for the management of postoperative pain. The paper is based on PubMed searches and the European Medicine Agency assessment report. Expert commentary: Under-treatment of acute pain is a substantial clinical problem. The initial experiences with the sublingual delivery system are encouraging. Sufentanil sublingual nanotablets intended for PCA device use are approved in Europe, and approval is pending in the United States.

Population pharmacokinetics and analgesic potency of oxycodone

AIMS

This prospective study aimed to characterize the population pharmacokinetics of intravenous oxycodone and to determine the minimum effective concentration (MEC) and minimum effective analgesic concentration (MEAC) of oxycodone for major open intra-abdominal surgery.

METHODS

In the pharmacokinetic study, patients were administered intravenous oxycodone (0.1 mg kg^-1 ), and arterial blood was sampled at pre-set intervals. In the analgesic-potency study, patients were administered intravenous oxycodone (0.1 mg kg^-1 ) 30 min before the end of the surgery, were placed in the postoperative anaesthesia care unit (PACU), and were asked to rate their pain every 10 min using a visual analogue scale (0 = no pain, 10 = most severe pain). On the first occasion that wound pain at rest and during compression was rated as ≥3 or ≥5, respectively, the first blood sample was obtained to determine the MEC. A second blood sample was obtained after titration with 2 mg of oxycodone to yield wound pain <3 at rest and <5 during wound compression, and MEAC was determined. MEC and MEAC were determined again in each patient.

RESULTS

In the population pharmacokinetic study (n = 54), oxycodone plasma concentration over time was well described by a three-compartment mammillary model. Lean body mass and age were significant covariates for the volume of distribution and metabolic clearance of the pharmacokinetic model of oxycodone, respectively. The analgesic-potency study (n = 50) showed that the median (95% CI) MEC and MEAC were 31.5 (19.2-42.8) and 74.1 (29.2-128.3) ng ml^-1 (first measurements) and 63.4 (15.6-120.1) and 76.1 (32.9-132.7) ng ml^-1 (second measurements), respectively.

CONCLUSIONS

In major intra-abdominal open surgery, the MEAC and analgesic potency of oxycodone were 75 ng ml^-1 and 60 ng ml^-1 , respectively.