Effects of parecoxib and dipyrone on platelet aggregation in patients undergoing meniscectomy: a double-blind, randomized, parallel-group study

Haemodynamics, side effects and safety of the combination of continuous femoral nerve block and intravenous parecoxib for pain management after Total Knee Arthroplasty: A pilot study

Background

Total Knee Arthroplasty (TKA) is a well-established surgical procedure for the treatment of knee joint diseases. This operation leads to severe acute and chronic pain, and intravenous administration of parecoxib could provide significant pain relief.

Objective

The aim of the study was to compare the hemodynamic data and safety profile of patients who received parecoxib compared to placebo following TKA.

Methods

Ninety patients were followed during this study and were randomly assigned into two equal groups. Group P received parecoxib and Group C received the placebo. Exclusion criteria included age < 40 or > 80 years, ASA III or higher, obesity (>140 kg), allergy to local anaesthetics, opioid dependence, contraindications for subarachnoid anaesthesia, femoral block or the administration of parecoxib.The haemodynamic data collected were Systolic Arterial Pressure (SAP), Diastolic Arterial Pressure (DAP), Heart Rate (HR), Oxygen Saturation (Ox-Sat), blood transfusion requirements and side effects. Recordings were performed every hour for up to 10 hours and at 15min, 4, 8, 12, 24, 36 hours postoperatively.

Results

The postoperative SAP and DAP data presented similar findings among groups (p>0.05) within the aforementioned time intervals. The postoperative HR data for both groups displayed no statistically significant difference between the two cohorts (p>0.05). Regarding the occurrence of transfusion, there is no statistically significant difference between the parecoxib and placebo cohorts. The frequency of side effects was negligible and could not be correlated with either group.

Conclusion

Therefore, parecoxib did not render any noticeable impact on the hemodynamic profile of the patients.

Impact of analgesic regimen on patient outcome following subarachnoid hemorrhage: positive adjuvant effects of metamizole

INTRODUCTION

Various analgesics are used to control intense headaches in patients following subarachnoid hemorrhage. In addition to pain control, it has been shown that some analgesics can affect various pathophysiological cascades. Therefore, we devised a study to assess whether the use of metamizole has a significant impact on the development of ischemic complications, hydrocephalus, and the overall outcome in patients following aneurysmal subarachnoid hemorrhage in the context of the other non-opioids and opioids effects.

METHODS

In our retrospective, single-center cohort study, we enrolled 192 patients diagnosed with subarachnoid hemorrhage. We recorded their initial clinical status, comorbidities, and the daily dosage of analgesics over 14 days of hospitalization after the onset of subarachnoid hemorrhage. Using univariate and subsequent multivariate logistic regression analysis, we assessed the influence of various factors, including analgesics, on the development of delayed cerebral ischemia and hydrocephalus, as well as on 2-week and 6-month outcomes.

RESULTS

Although the administration of non-opioids, in general, had no effect on the development of delayed cerebral ischemia or hydrocephalus, the use of metamizole as the main analgesic was associated with a significantly lower chance of poor outcome at both 2-weeks and 6-months, as well as the development of delayed cerebral ischemia. As opioids were indicated primarily for analgosedation in mechanically ventilated patients with poor clinical status, their usage was associated with a significantly higher chance of poor outcome, delayed cerebral ischemia, and hydrocephalus.

CONCLUSION

Our results suggest that the prescription of metamizole may be associated with better outcomes and a lower chance of delayed cerebral ischemia development in patients after subarachnoid hemorrhage. Considering the retrospective nature of our study and the limited worldwide availability of metamizole due to its prohibition in some countries, our results do not demonstrate a clear benefit but rather justify the need for subsequent prospective studies.

Pharmacokinetics of dipyrone in horses: A multi-dose, dose escalation study

Dipyrone is a non-opioid, nonsteroidal anti-inflammatory drug with antipyretic and analgesic properties commonly used in horses. Dipyrone is rapidly hydrolyzed to the primary active metabolite 4-methylaminoantipyrine (4-MAA). The purpose of this study was to determine the pharmacokinetic profile of 4-MAA following repeated and escalating doses of intravenously administered dipyrone. Twenty-six horses were randomly allocated to five treatment groups (one placebo group and four dipyrone groups [30 mg/kg q8h, 30 mg/kg q12h, 60 mg/kg q8h, and 90 mg/kg q12h]) and treated for nine consecutive days. Blood was collected at predetermined timepoints, and plasma was analyzed for 4-MAA concentrations with a validated LC/MS/MS method. Following a single dose, there was a linear correlation to the maximum concentration (Cmax ) achieved. There was a disproportionate increase in the minimum concentration (Cmin ) of 4-MAA with accumulation occurring at higher doses or more frequent dosing intervals. Significant differences were noted in 4-MAA Cmax , half-life, and area under the curve during the dosing interval (AUCtau ) when dipyrone was administered at 30 mg/kg q12h versus q8h. Adverse effects attributed to drug administration were not noted.

The efficacy of parecoxib for pain control after hysterectomy: a meta-analysis of randomized controlled studies

Introduction: The efficacy of parecoxib for pain control after hysterectomy remains controversial. We conduct a systematic review and meta-analysis to explore the influence of parecoxib versus placebo on pain intensity after hysterectomy.Methods: We search PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases through March 2019 for randomized controlled trials (RCTs) assessing the effect of parecoxib versus placebo on pain intensity after hysterectomy. This meta-analysis is performed using the random-effect model.Results: Six RCTs are included in the meta-analysis. Overall, compared with control group after hysterectomy, parecoxib treatment is associated with substantially reduced pain scores in 4-6 h at rest (MD = -0.98; 95%CI = -1.14 to -0.81; p < .00001), pain scores in 12 h at rest (MD = -0.70; 95%CI = -0.77 to -0.63; p < .00001), pain scores in 12 h on sitting up (MD = -0.90; 95%CI = -1.03 to -0.77; p < .00001), pain scores in 24 h on sitting up (MD = -1.19; 95%CI = -1.94 to -0.44; p = .002), dose of analgesic need in parecoxib group is notably lower than that in control group (std. MD = -2.54; 95%CI = -3.97 to -1.10; p = .0005), but shows no obvious effect on pain scores in 24 h at rest (MD = -0.40; 95%CI = -1.47-0.67; p = .47), pain scores in 4-6 h on sitting up (MD = -0.54; 95%CI = -2.50-1.42; p = .59), first time to analgesic requirement between two groups (std. MD = -0.10; 95%CI = -0.47-0.26; p = .57), nausea or vomiting (RR = 0.92; 95%CI = 0.59-1.43; p = .70), and adverse events (RR = 0.86; 95%CI = 0.64-1.17; p = .34).Conclusions: Parecoxib treatment provides additional benefits for pain control after hysterectomy.

Metamizole vs. ibuprofen at home after day case surgery: A double-blind randomised controlled noninferiority trial

BACKGROUND

NSAIDs and paracetamol are the cornerstones of pain treatment after day case surgery. However, NSAIDs have numerous contraindications and consequently are not suitable in up to 25% of patients. Metamizole is a non-opioid compound with a favourable gastro-intestinal and cardiovascular profile compared with NSAIDs.

OBJECTIVES

The study aimed to assess if a combination of metamizole and paracetamol is noninferior to a combination of ibuprofen and paracetamol in treating pain at home after painful day case surgery.

DESIGN

A double-blind randomised controlled trial.

SETTING

Single centre.

PATIENTS

Two hundred patients undergoing elective ambulatory haemorrhoid surgery, arthroscopic shoulder or knee surgery, or inguinal hernia repair.

INTERVENTION

Patients were randomly allocated to receive either metamizole and paracetamol (n = 100) or ibuprofen and paracetamol (n = 100) orally for four days.

MAIN OUTCOME MEASURES

Average postoperative pain intensity using a numerical rating scale and use of rescue medication were measured in the postanaesthesia care unit (PACU) and on postoperative days (POD) 1 to 3. A difference in mean numerical rating scale score of 1 point or less was considered noninferior. Adverse effects of study medication and satisfaction with study medication were measured on PODs 1 to 3 by telephone follow-up.

RESULTS

In the PACU, the difference in mean ± SD pain score between metamizole and paracetamol and ibuprofen and paracetamol was 0.85 ± 0.78. From POD 1 to 3, this difference was lower than 1, resulting in noninferiority. Rescue opioid consumption in the PACU and on PODs 1 and 3 was not significantly different between treatment groups. Rescue opioid consumption on POD2 was significantly higher in the ibuprofen and paracetamol group (P = 0.042). Adverse effects of study medication and overall patient satisfaction were similar in both groups.

CONCLUSION

Paracetamol/metamizole and paracetamol/ibuprofen are equally effective in treatment of acute postoperative pain at home after ambulatory surgery with comparable patient satisfaction levels.

TRIAL REGISTRATION

European Union Clinical Trials Register 2015-003987-35.

[Pain therapy for children and adolescents with hemophilia : Recommendations by an expert panel]

BACKGROUND

Children and adolescents with severe hemophilia commonly suffer from acute and chronic pain as a consequence of hemophilia-related bleeding. Intervention-related pain also plays a major role. Despite its high prevalence in this patient group, hemophilia-related pain is not always adequately addressed and sufficiently treated.

OBJECTIVES

This paper discusses how to improve pain management for children and adolescents (0-18 years) with hemophilia and which specific features in this population should influence decisions in pain management.

MATERIALS AND METHODS

An expert panel discussed challenges in pain treatment in children and adolescents with hemophilia. Recommendations are based on evidence and clinical experience.

RESULT

Pain management in children with hemophilia needs improvement. Children with hemophilia are at risk of developing chronic pain and of suffering traumatization due to insufficient pain management. Pain therapy can be challenging in these children as both their age and the underlying disease limit the options in particular in pain medication. The expert panel developed recommendations to improve pain management in children with hemophilia.

Metamizole inhibits arachidonic acid-induced platelet aggregation after surgery and impairs the effect of aspirin in hospitalized patients

PURPOSE

The inhibitory effect of metamizole on platelet aggregation is known for several years, but most studies were conducted in healthy volunteers with contradictory results. Recent studies have shown an inhibitory effect of metamizole on acetylsalicylic acid (ASA)-induced platelet aggregation. We aimed to investigate the effect of metamizole on platelet aggregation after an elective surgery and the effect of metamizole on ASA-induced platelet aggregation in hospitalized patients.

METHODS

We performed platelet aggregation analysis after induction with ADP, arachidonic acid (AA), epinephrine, and collagen in 37 patients prior to an elective visceral or thoracic surgery and on postoperative day (POD) 1 and POD 3 1-2 h and 5-6 h after metamizole. In another cohort of 10 hospitalized patients receiving the combination of metamizole and ASA for more than 7 days, AA-induced platelet aggregation was analyzed in the morning prior to the intake of both drugs.

RESULTS

Metamizole induced a strong inhibitory effect on AA-induced platelet aggregation at all time points being detectable up to 41 h in some patients. Besides a less pronounced effect on collagen-induced platelet aggregation on POD 3 1-2 h after metamizole, all other inductors showed no effect. In 4 out of 10 hospitalized patients, no ASA-induced inhibition of platelet aggregation was detectable without correlation to sequence of administration.

CONCLUSIONS

The reason why some patients have a long-lasting inhibitory effect of metamizole on COX-induced platelet aggregation that might interfere with ASA should be investigated in a larger cohort of patients.

Evaluation of hematological alterations after therapeutic use of dipyrone in healthy adults: a prospective study

Background Dipyrone is a non-narcotic analgesic/antipyretic widely used in some countries but prohibited in others due to suspected risk of agranulocytosis. The primary goal of this study was to evaluate hematological alterations in healthy adult volunteers after treatment with dipyrone. Methods The study enrolled 30 healthy volunteers of both genders, aged 19-37 years. They received tablets containing 500 mg of dipyrone sodium to be used four times daily for 7 consecutive days. Before the first administration, arterial pressure was measured and blood was collected in order to evaluate hematological baseline parameters. On the 8th day after the beginning of treatment, the volunteers had their blood pressure assessed once more and underwent a second blood draw. Total and specific leukocyte counts, creatinine, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), erythrocytes, and platelets were quantitatively determined. Results No statistically significant difference was observed among total or specific leukocyte counts. Number of platelets, erythrocytes, hemoglobin, and hematocrit decreased after treatment. Diastolic pressure, mean arterial pressure (MAP), and urea concentration declined, while creatinine, AST, and ALT showed no significant alterations. It is noteworthy that, even for parameters that showed statistically significant changes, the highest and lowest values remained within the normal ranges. Conclusions Although dipyrone has historically been associated with agranulocytosis, leukocyte counts remained practically unchanged after oral administration of dipyrone. On the other hand, the present study adds evidence that dipyrone is able to produce statistically relevant decrease in number of platelets, erythrocytes, hemoglobin, and hematocrit in healthy adults, even after short-term treatment.

Efficacy and safety of Parecoxib for prevention of catheter-related bladder discomfort in patients undergoing transurethral resection of bladder tumor: Prospective randomised trial

Background and Aims:

Catheter-related bladder discomfort (CRBD) is the urge to void or discomfort in the suprapubic region secondary to an indwelling urinary catheter. We aimed to evaluate the safety and efficacy of single-dose of intravenous parecoxib in reducing the incidence and severity of CRBD in patients undergoing transurethral resection of bladder tumor (TURBT).

Methods:

Sixty-one adult patients, American Society of Anesthesiologists physical status I or II, undergoing elective TURBT under spinal anaesthesia, were randomly allocated to receive 40 mg of IV parecoxib (group P; n = 29) or an equal volume of normal saline (control group C; n = 32). CRBD was graded as none, mild, moderate, and severe. Between-group comparisons were made for the incidence and severity of CRBD, postoperative Visual analog scales (VAS), rescue analgesia equirements, and occurrence of adverse events. Statistical analysis done with the Mann–Whitney U-test and Fisher's Exact Test. A P value of ≤ 0.05 was considered statistically significant.

Results:

Parecoxib significantly reduced the incidence and severity of CRBD at 2, 4, 6, and 12 hours postoperatively compared to placebo (P < 0.05). Median pain VAS scores were lower in the P group at all times except the first hour. Rescue analgesia was given to more patients in group C (16/32, 50%) than in group P (1/29) (P < 0.001). None of the patients who received parecoxib experienced an adverse event.

Conclusion:

A single intravenous injection of parecoxib is safe and effective in decreasing the incidence and severity of CRBD in patients undergoing TURBT.

Trial Registration Identifier:

NCT02729935(www.clinicaltrials.gov).

[Metamizole (dipyrone): mode of action, drug-drug interactions, and risk of agranulocytosis]

Metamizole (dipyrone) is a nonsteroidal compound with strong analgesic as well as antipyretic and spasmolytic properties. Based on a small number of cases of agranulocytosis, metamizole was withdrawn from the market in some countries. Other countries restricted its use. This paper discusses the safety aspects of metamizole and compares it with other compounds used for similar indications.

The using of a piglets as a model for evaluating the dipyrone hematological effects

BACKGROUND

Dipyrone (MET, metamizole) is a non-steroidal anti-inflammatory drug commonly used both in human and in veterinary medicine. After oral administration, is broken down rapidly to metabolites which largely retain the activity of the parent drug. Its metabolites have analgesic, antipyretic and anti-inflammatory effects.

RESULTS

The subjects were eight healthy male Large White post-suckling piglets, weighing between 5.0 to 7.4 kg, of ages 35 ± 10 days. The animals were administered MET (100 mg/kg) by an intramuscular (I.M.) injection. The study calculated the value of several hemorheological parameters. Significant impact of MET treatment (p < 0.05) was proven in case: activated partial thromboplastin time; ratio of activated partial thromboplastin time; hemoglobin; hematocrit; mean corpuscular hemoglobin; mean corpuscular volume; red blood cells volume; white blood cells volume; prothrombin time index.

CONCLUSIONS

In summation, our observations suggest that a piglet model is useful for studying the impact of MET on hemorheological parameters.

Effect of Parecoxib as an Adjunct to Patient-Controlled Epidural Analgesia after Abdominal Hysterectomy: A Multicenter, Randomized, Placebo-Controlled Trial

Objective

This multicenter, randomized, placebo-controlled study evaluated the efficacy and side effects of parecoxib during patient-controlled epidural analgesia (PCEA) after abdominal hysterectomy.

Methods

A total of 240 patients who were scheduled for elective abdominal hysterectomy under combined spinal-epidural anesthesia received PCEA plus postoperative intravenous parecoxib 40 mg or saline every 12 h for 48 h after an initial preoperative dose of parecoxib 40 mg or saline. An epidural loading dose of a mixture of 6 mL of 0.25% ropivacaine and 2 mg morphine was administered 30 min before the end of surgery, and PCEA was initiated using 1.25 mg/mL ropivacaine and 0.05 mg/mL morphine with a 2-mL/h background infusion and 2-mL bolus with a 15-min lockout. The primary end point of this study was the quantification of the PCEA-sparing effect of parecoxib.

Results

Demographic data were similar between the two groups. Patients in the parecoxib group received significantly fewer self-administrated boluses (0 (0, 3) vs. 7 (2, 15), P < 0.001) and less epidural morphine (5.01 ± 0.44 vs. 5.95 ± 1.29 mg, P < 0.001) but experienced greater pain relief compared with the control group (P < 0.001). Patient global satisfaction was higher in the parecoxib group than the control group (P < 0.001). Length of hospitalization (9.50 ± 2.1, 95% CI 9.12~9.88 vs. 10.41 ± 2.6, 95% CI 9.95~10.87, P = 0.003) and postoperative vomiting (17% vs. 29%, P < 0.05) were also reduced in the parecoxib group. There were no serious adverse effects in either group.

Conclusion

Our data suggest that adjunctive parecoxib during PCEA following abdominal hysterectomy is safe and efficacious in reducing pain, requirements of epidural analgesics, and side effects.

Trial Registration

ClinicalTrials.gov (NCT01566669)

Efficacy and safety of Postoperative Intravenous Parecoxib sodium Followed by ORal CElecoxib (PIPFORCE) post-total knee arthroplasty in patients with osteoarthritis: a study protocol for a multicentre, double-blind, parallel-group trial

INTRODUCTION

Total knee arthroplasty (TKA) has been regarded as a most painful orthopaedic surgery. Although many surgeons sequentially use parecoxib and celecoxib as a routine strategy for postoperative pain control after TKA, high quality evidence is still lacking to prove the effect of this sequential regimen, especially at the medium-term follow-up. The purpose of this study, therefore, is to evaluate efficacy and safety of postoperative intravenous parecoxib sodium followed by oral celecoxib in patients with osteoarthritis (OA) undergoing TKA. The hypothesis is that compared to placebo with opioids as rescue treatment, sequential use of parecoxib and celecoxib can achieve less morphine consumption over the postoperative 2 weeks, as well as better pain control, quicker functional recovery in the postoperative 6 weeks and less opioid-related adverse events during the 12-week recovery phase.

METHODS AND ANALYSIS

This study is designed as a multicentre, randomised, double-blind, parallel-group and placebo-controlled trial. The target sample size is 246. All participants who meet the study inclusion and exclusion criteria will be randomly assigned in a 1:1 ratio to either the parecoxib/celecoxib group or placebo group. The randomisation and allocation will be study site based. The study will consist of three phases: an initial screening phase; a 6-week double-blind treatment phase; and a 6-week follow-up phase. The primary end point is cumulative opioid consumption during 2 weeks postoperation. Secondary end points consist of the postoperative visual analogue scale score, knee joint function, quality of life, local skin temperature, erythrocyte sedimentation rate, C reactive protein, cytokines and blood coagulation parameters. Safety end points will be monitored too.

ETHICS AND DISSEMINATION

Ethics approval for this study has been obtained from the Ethics Committee, Peking Union Medical College Hospital, China (Protocol number: S-572) Study results will be available as published manuscripts and presentations at national and international meetings.

TRIAL REGISTRATION NUMBER

NCT02198924.

Parecoxib sodium reduces the need for opioids after tonsillectomy in children: a double-blind placebo-controlled randomized clinical trial

OBJECTIVE

Postoperative pain is a common phenomenon after pediatric tonsillectomy. This prospective randomized double-blind placebo-controlled clinical trial was performed to evaluate the analgesic efficacy of intravenous parecoxib sodium in children undergoing tonsillectomy.

METHODS

Sixty children (American Society of Anesthesiologists physical status I-III, aged three to seven years, and scheduled to undergo elective tonsillectomy under general anesthesia) were randomly allocated into one of two groups to receive intravenous parecoxib sodium 1 mg·kg(-1) (Group P, n = 30) or the same volume of saline (Group S, n = 30) just after induction of general anesthesia. Between-group comparisons were made for the number of patients requiring rescue morphine, total number of doses of postoperative rescue morphine, time to first rescue analgesic, postoperative pain and sedation scores, and adverse effects.

RESULTS

Rescue morphine was given to more children in Group S (25/30, 83%) than in Group P (17/30, 57%) [relative risk (RR), 1.5; 95% confidence interval (CI), 1.0 to 2.1; P = 0.024]. The mean (SD) time to first rescue analgesic was shorter in Group S than in Group P [132 (54) min vs 193 (78) min, respectively; mean difference, 61; 95% CI, 26.6 to 96.1; P = 0.001]. The median (interquartile range [IQR]) Children's Hospital of Eastern Ontario Pain Scale scores in the postanesthesia care unit were lower in Group P than in Group S (7 [5-8] vs 9 [8-11], respectively; P = 0.001). The incidence of postoperative nausea and vomiting (PONV) was higher in Group S than in Group P [11/30 (37%) vs 4/30 (13%), respectively; RR, 2.8; 95% CI, 1.0 to 7.7; P = 0.037].

CONCLUSIONS

A single intravenous injection of parecoxib sodium 1 mg·kg(-1) after anesthesia induction is an effective method for the control of postoperative pain. It provides a morphine-sparing effect, prolongs the time to first rescue analgesic, and reduces PONV in children undergoing tonsillectomy.

Efficacy of celecoxib for acute pain management following total hip arthroplasty in elderly patients: A prospective, randomized, placebo-control trial

The aim of the present study was to determine whether celecoxib is able to ameliorate pain intensity, provide a narcotic-sparing effect, achieve early ambulation and improve rehabilitation following total hip arthroplasty (THA) in elderly patients. Peri- and post-operative oral celecoxib was administered to verify the efficacy of celecoxib for acute pain management in a multimodal analgesic strategy. All 64 eligible patients were randomly allocated to either the celecoxib group, who took an oral 400 mg capsule of celecoxib peri-operatively and 200 mg per 12 h post-operatively for the first 5 days, or the control group, who were orally treated with a placebo capsule having the same appearance. A multimodal analgesic technique was used in which oral celecoxib or placebo capsule was combined with intravenous patient-controlled analgesia (PCA) morphine pump for peri- and post-operative pain management. Pain assessments were recorded at 6, 12, 24, 48 and 72 h, and 7 and 14 days after THA using the visual analog scale (VAS). PCA morphine consumption; 6, 12, 24 and 48-h post-operative Harris hip score (HHS); time interval until initial ambulation; rates of urinary retention and post-operative nausea and vomiting (PONV) within 72 h; and intra- and post-operative blood loss were also documented. The celecoxib and control groups comprised 34 and 30 patients, respectively. Baseline demographics were comparable between the two groups. The post-operative VAS in the celecoxib group was significantly lower than that in the control group at 12, 24, 48 and 72 h after THA. The post-operative HHS had no significant difference between the two groups, while the time interval until initial ambulation in the celecoxib group (4.5±1.2 days) was significantly less than that in the control group (5.83±2.04 days; P<0.05). Morphine consumption was significantly decreased in the celecoxib group when compared with the control group at 6, 12, 24 and 24 h. Although the 72-h post-operative rates of urinary retention and PONV were lower in the celecoxib group than in the control group, there were no significant differences in these rates between the two groups. The intra- or post-operative blood loss was not significantly different between groups. In conclusion, pre-and post-operative oral celecoxib in a multimodal analgesic strategy can achieve favorable pain relief, reduce opioid consumption, and provide earlier ambulation and improved rehabilitation when compared with PCA morphine alone following THA in elderly patients.

[Pediatric perioperative systemic pain therapy: Austrian interdisciplinary recommendations on pediatric perioperative pain management]

BACKGROUND

Many analgesics used in adult medicine are not licensed for pediatric use. Licensing limitations do not, however, justify that children are deprived of a sufficient pain therapy particularly in perioperative pain therapy. The treatment is principally oriented to the strength of the pain. Due to the degree of pain caused, intramuscular and subcutaneous injections should be avoided generally.

NON-OPIOIDS

The basis of systemic pain therapy for children are non-opioids and primarily non-steroidal anti-inflammatory drugs (NSAIDs). They should be used prophylactically. The NSAIDs are clearly more effective than paracetamol for acute posttraumatic and postoperative pain and additionally allow economization of opioids. Severe side effects are rare in children but administration should be carefully considered especially in cases of hepatic and renal dysfunction or coagulation disorders. Paracetamol should only be taken in pregnancy and by children when there are appropriate indications because a possible causal connection with bronchial asthma exists. To ensure a safe dosing the age, body weight, duration of therapy, maximum daily dose and dosing intervals must be taken into account. Dipyrone is used in children for treatment of visceral pain and cholic. According to the current state of knowledge the rare but severe side effect of agranulocytosis does not justify a general rejection for short-term perioperative administration.

OPIOIDS

In cases of insufficient analgesia with non-opioid analgesics, the complementary use of opioids is also appropriate for children of all age groups. They are the medication of choice for episodes of medium to strong pain and are administered in a titrated form oriented to effectiveness. If severe pain is expected to last for more than 24 h, patient-controlled anesthesia should be implemented but requires a comprehensive surveillance by nursing personnel.

KETAMINE

Ketamine is used as an adjuvant in postoperative pain therapy and is recommended for use in pediatric sedation and analgosedation.

The pharmacokinetics and in vitro/ex vivo cyclooxygenase selectivity of parecoxib and its active metabolite valdecoxib in cats

Parecoxib (PX) is an injectable prodrug of valdecoxib (VX, which is a selective cyclo-oxyganase-2 (COX-2)) inhibitor licensed for humans. The aim of the present study was to evaluate pharmacokinetics and in vitro/ex vivo cyclooxygenase selectivity of PX and VX in cats. In a whole blood in vitro study, PX did not affect either COX enzymes whereas VX revealed a COX-2 selective inhibitory effect in feline whole blood. The IC50 values of VX for COX-2 and COX-1 were 0.45 and 38.6 µM, respectively. Six male cats were treated with 2.5 mg/kg of PX by intramuscular injection. PX was rapidly converted to VX with a relatively short half-life of 0.4 h. VX achieved peak plasma concentration (2.79 ± 1.59 µg/mL) at 7 h following PX injection. The mean residence times for PX and VX were 0.43 ± 0.15 and 5.94 ± 0.88 h, respectively. In the ex vivo study, PX showed a COX-2 inhibition rate of about 70% in samples taken at 1, 2, 4 and 10 h after injection, with a significant difference compared to the control. In contrast, COX-1 was slightly inhibited, ranging from 0.7% to 9.7% of the control inhibition rate without any significant difference for 24 h after PX administration. The preliminary findings of the present research appear promising and encourage further studies to investigate whether PX can be successfully used in feline medicine.

Efficacy and safety of parecoxib sodium for acute postoperative pain: A meta-analysis

This meta-analysis was performed to evaluate the efficacy and safety of parecoxib sodium for acute postoperative pain. PubMed, Cochrane Central Register of Controlled Trials, EBSCO, Springer, Ovid and Chinese National Knowledge Infrastructure (CNKI) databases were searched from January 1999 to January 2013 to comprehensively collect randomized controlled trials (RCTs) of parecoxib sodium for acute postoperative pain. The methodological quality of the included RCTs were assessed and the data were extracted by two reviewers independently according to the Cochrane Handbook. Efficacies and safety (respiratory depression, pruritus, fever, headache, and nausea and vomiting) were pooled using meta-analysis performed by Review Manager 5.1 software. Relative risk (RR) and 95% confidence interval (CI) were calculated in a fixed-effects model. Seven RCTs involving 1,939 patients met the inclusion criteria. The results of the meta-analysis revealed that the rate of 'effective' treatment as described by the patients' global evaluation of study medication (PGESM) was higher in the patient-controlled analgesia (PCA) combined with parecoxib sodium group 24, 48, and 72 h after the initial intravenous dose of 40 mg parecoxib compared with that in the control group [PCA alone; RR=1.41, 95% CI (1.13-1.75); RR=1.25, 95% CI (1.15-1.35); and RR=1.30, 95% CI (1.21-1.40), respectively]. The rate of 'ineffective' treatment in the PCA combined with parecoxib sodium group was lower compared with that of the control group [RR=0.43, 95% CI (0.26-0.72); RR= 0.44, 95% CI (0.34-0.57); and RR= 0.33, 95% CI (0.23-0.48), respectively]. Combination of PCA with parecoxib sodium reduced the incidence of postoperative fever [RR=0.34, 95% CI (0.22-0.53)], as well as nausea and vomiting [RR=0.69, 95% CI (0.57-0.83)]; however, it did not significantly reduce respiratory depression [RR= 0.84, 95% CI (0.38-1.83)], pruritus [RR= 0.91, 95% CI (0.54-1.52)] or headache [RR=0.77, 95% CI (0.47-1.28)]. The combination of PCA with parecoxib sodium successively injected for <3 days significantly increases the scores of PGESM and reduces the incidence of adverse effects and postoperative complications.

Parecoxib added to ropivacaine prolongs duration of axillary brachial plexus blockade and relieves postoperative pain

BACKGROUND

Cyclooxygenase (COX)-2 antagonist is widely used for intravenous postoperative pain relief. Recent studies reported COX-2 in the spinal dorsal horn could modulate spinal nociceptive processes. Epidural parecoxib in rats showed no neurotoxicity. These findings suggested applying a COX-2 antagonist directly to the central or peripheral nerve might provide better analgesia.

QUESTIONS/PURPOSES

We therefore determined: (1) whether the addition of parecoxib to ropivacaine injected locally on the nerve block affected the sensory and motor block times of the brachial plexus nerve block; and (2) whether parecoxib injected locally on the nerve or intravenously had a similar analgesic adjuvant effect.

METHODS

We conducted a randomized controlled trial from January 2009 to November 2010 with 150 patients scheduled for elective forearm surgery, using a multiple-nerve stimulation technique. Patients were randomly allocated into one of three groups: Group A (n = 50) received ropivacaine 0.25% alone on the brachial plexus nerve; Group B (n = 50) received ropivacaine together with 20 mg parecoxib locally on the nerve block; and Group C (n = 50) received 20 mg parecoxib intravenously. We recorded the duration of the sensory and motor blocks, and the most severe pain score during a 24-hour postoperative period.

RESULTS

Parecoxib added locally on the nerve block prolonged the motor and sensory block times compared with Group A. However, parecoxib injected intravenously had no such effect. Pain intensity scores in Group B were lower than those in Groups A and C.

CONCLUSIONS

Parecoxib added to ropivacaine locally on the nerve block prolonged the duration of the axillary brachial plexus blockade and relieved postoperative pain for patients having forearm orthopaedic surgery.

LEVEL OF EVIDENCE

Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Evaluation of medication safety in the discharge medication of 509 surgical inpatients using electronic prescription support software and an extended operational interaction classification

PURPOSE

Our aim was to study drug interactions and dose adjustments in patients with renal impairment in the discharge medication of surgical inpatients and to evaluate the strengths and limitations of clinical decision support software (CDSS) for this task.

METHODS

This was a cross-sectional study involving 509 surgical patients of a primary care hospital. We developed a customized interface for the CDSS MediQ, which we used for automated retrospective identification of drug interactions in the patients' discharge medication. The clinical relevance of the interactions was evaluated based on the Zurich Interaction System (ZHIAS) that incorporates the operational classification of drug interactions (ORCA). Prescriptions were further analyzed for recommended dose adjustments in patients with a glomerular filtration rate <60 ml/min.

RESULTS

For the total of 2,729 prescriptions written for the 509 patients enrolled in the study, MediQ generated 2,558 interaction alerts and 1,849 comments. Among these were ten "high danger" and 551 "average danger" alerts that we reclassified according to ORCA criteria. This reclassification resulted in ten contraindicated combinations, 77 provisionally contraindicated combinations, and 310 with a conditional and 164 with a minimal risk of adverse outcomes. The ZHIAS classification also provides categorical information on expected adverse outcomes and management recommendations, which are presented in detail. We identified 56 prescriptions without a recommended dose adjustment for impaired renal function.

CONCLUSIONS

CDSS identified a large number of drug interactions in surgical discharge medication, but according to ZHIAS criteria only a minor fraction of these appeared to involve a substantial risk to the patient. CDSS should therefore aim at reducing over-alerting and improve usability in order to become more efficacious in terms of the prevention of adverse drug events in clinical practice.

Influence of COX-inhibiting analgesics on the platelet function of patients with subarachnoid hemorrhage

BACKGROUND

Platelet function of patients with subarachnoid hemorrhage (SAH) may play an important part in both rebleeding and delayed cerebral ischemia, but little is known about aggregation pathways during the acute phase of stroke. Analgesics are used regularly in the first days after bleeding, and some can potentially inhibit the cyclooxygenase (COX) enzyme. We examined the platelet function of patients with SAH in order to describe their basal situation and determine whether the administration of intravenous nonsteroidal antiinflammatory drugs (NSAIDs) affected platelet aggregation.

METHODS

Arachidonic acid (AA)-induced aggregation and the platelet function analyzer (PFA)-100 test with collagen/epinephrine cartridges were used to study a group of SAH patients that was treated with dexketoprofen and dipyrone and to compare them to patients that had received no analgesia.

RESULTS

Ninety-six consecutive SAH patients prospectively enrolled in platelet studies. Twenty-seven patients were taking NSAIDs (10 on dexketoprofen and 17 on dipyrone), and there were 15 cases in the control group. AA-induced aggregation was 10% ± 3.2% for NSAIDs (mean ± standard error), specifically 17.2% ± 7% for dexketoprofen and 5.7% ± 1% for dipyrone. Aggregation in the control group was 72.4% ± 6% (P = .001). Both analgesics slowed the platelet plug formation during the PFA-100 test, with closure times of 237.2 ± 25 seconds for dexketoprofen and 198.4 ± 22 seconds for dipyrone and 138.1 ± 21 seconds in controls (P = .02).

CONCLUSIONS

The administration of COX-inhibiting analgesics leads to an hypoaggregability state in the first days of SAH. Further insight into their impact on complications such as rebleeding and delayed cerebral ischemia is needed in order to optimize the headache treatment of SAH.

Intravenous or intramuscular parecoxib for acute postoperative pain in adults

BACKGROUND

Parecoxib was the first COX-2 available for parenteral administration, and may, given intravenously or intramuscularly, offer advantages over oral medication when patients have nausea and vomiting or are unable to swallow, such as in the immediate postoperative period.

OBJECTIVES

Assess the efficacy of single dose intravenous or intramuscular parecoxib in acute postoperative pain, the requirement for rescue medication, and any associated adverse events.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE in November 2008.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of parecoxib compared with placebo for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. The area under the "pain relief versus time" curve was used to derive the proportion of participants with parecoxib and placebo experiencing at least 50% pain relief over 6 hours, using validated equations. The number-needed-to-treat-to-benefit (NNT) was calculated using 95% confidence intervals (CI). The proportion of participants using rescue analgesia over a specified time period, and time to use of rescue analgesia, were sought as additional measures of efficacy. Information on adverse events and withdrawals were also collected.

MAIN RESULTS

Seven studies (1446 participants) were included. There was no significant difference between doses, or between intravenous and intramuscular administration for 50% pain relief over 6 hours: NNTs compared with placebo were 3.1 (2.4 to 4.5), 2.4 (2.1 to 2.8), and 1.8 (1.5 to 2.3) for 10, 20, and 40 mg parecoxib respectively. Fewer participants required rescue medication over 24 hours with parecoxib than placebo: parecoxib 40 mg was significantly better than parecoxib 20 mg (NNTs to prevent use of rescue medication 7.5 (5.3 to 12.8) and 3.3 (2.6 to 4.5) respectively; P < 0.0007). Median time to use of rescue medication was 3.1 hours, 6.9 hours and 10.6 hours with parecoxib 10 mg, 20 mg and 40 mg respectively, and 1.5 hours with placebo. Adverse events were generally mild to moderate, rarely led to withdrawal, and did not differ in frequency between groups. No serious adverse events were reported with parecoxib or placebo.

AUTHORS' CONCLUSIONS

A single dose of parecoxib 20 mg or 40 mg provided effective analgesia for 50 to 60% of those treated compared to about 15% with placebo, and was well tolerated. Duration of analgesia was longer, and significantly fewer participants required rescue medication over 24 hours with the higher dose.

The effects of nonsteroidal anti-inflammatory drugs on platelet function and severity of upper gastrointestinal haemorrhage

Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastrointestinal (GI) damage primarily due to the inhibition of prostaglandin synthesis in gastric mucosa, which is an important factor in mucosa protection. Platelets are a cardinal feature of vascular repair. A variety of angiogenic stimulators are stored in platelets and are released during clotting at the wound. When there is a defect in any of these functions and/or platelet number, haemostasis is usually impaired and there may be an associated increased risk and severity of bleeding. While the mechanism of mucosal injury and bleeding are well documented with the use of NSAIDs, very little is known about the platelet function abnormalities and their effects on severity of upper GI bleedings. We performed a prospective analysis of 49 patients who had a history of NSAIDs use to investigate the association between the platelet function impairment associated with NSAIDs and severity of upper GI haemorrhages. Thirty-six of 49 patients (73.5%) had deteriorated platelet function. Mean severity score of patients with deteriorated platelet functions was 3.39, and that of patients with normal platelet functions was 2.46. Mean severity score was statistically significantly higher in patients with deteriorated platelet functions. In conclusion, impaired platelet functions associated with NSAIDs may cause more severe upper GI bleeding. Clinicians should be alert for GI complications especially in older patients and in those with a history of ulcer bleeding.

Intravenous parecoxib for acute postoperative pain in adults

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the efficacy and adverse effects of single dose parecoxib in studies of acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.