A comparison of port-site infiltration with bupivacaine alone vs. bupivacaine plus dexemedetomidine after diagnostic staging laparoscopy.

Objectives: To compare the effects of bupivacaine alone and in combination with dexmedetomidine following staging laparoscopies. METHODS: This triple-blinded, prospective study was conducted from June to September 2021 at a tertiary care cancer hospital in Lahore, Pakistan, and comprised adult patients having American Society of Anaesthesiologists grade I-III, weighing >30kg and undergoing diagnostic staging laparoscopy. The subjects were randomised into two equal groups. Group A received 6ml of 2mg/kg bupivacaine at each of the four laparoscopic port sites before skin closure, while group B additionally received 2µg/kg dexmedetomidine. The presence and severity of pain were recorded and assessed at 15 min, 1, 2 and 4 hours as well as at the time of discharge from the post-anaesthesia care unit. The time to first request for rescue analgesia, total morphine consumption, and the occurrence of any side effects during their stay were also recorded. Data was analysed using SPSS 23. RESULTS: Of the 30 patients, 15(50%) were in group A; 10(66.6%) males and 5(33.3%) females with mean age 43.27±7.59 years. There were 15(50%) patients in group B; 12(80%) males and 3(20%) females with mean age 41.36±12.42 years (p>0.05). Of the total, 29(96.66%) patients were classified as American Society of Anaesthesiologists grade II, and 1(3.33%) patient in group A was grade III. There was no significant difference between the groups in any of the outcome measures assessed (p>0.05), and none of the patients experienced any side effect throughout the post-operative stay. CONCLUSIONS: The combination of dexmedetomidine and bupivacaine had no significant improvement in pain relief compared to bupivacaine alone.

Tramadol-paracetamol for postoperative pain after spine surgery - A randomized, double-blind, placebo-controlled study.

OBJECTIVES: Multimodal pain management is one component in enhanced recovery after surgery protocol. Here we evaluate the efficacy of tramadol-paracetamol in acute postoperative pain and pain outcome at 12 months after spine surgery in randomized, double-blind, placebo-controlled trial. METHODS: We randomized 120 patients undergoing spine surgery to receive, for add-on pain management, two tramadol-paracetamol 37.5 mg/325 mg (n = 61) or placebo tablets (n = 59) twice a day for 5 postoperative days. In the hospital, multimodal pain management consisted of dexketoprofen and oxycodone. After discharge, patients were prescribed ibuprofen 200 mg, maximum 1,200 mg/day. Pain, analgesic use, and satisfaction with pain medication were followed up with the Brief Pain Inventory questionnaire before surgery and at 1 and 52 weeks after surgery. The primary outcome was patients' satisfaction with pain medication 1 week after surgery. RESULTS: At 1 week after surgery, patients' satisfaction with pain medication was similarly high in the two groups, 75% [interquartile range, 30%] in the placebo group and 70% [40%] in the tramadol-paracetamol group (p = 0.949) on a scale: 0% = not satisfied, 100% = totally satisfied. At 1 week, ibuprofen dose was lower in the placebo group 200 mg [1,000] compared to the tramadol-paracetamol group, 800 mg [1,600] (p = 0.016). There was no difference in the need for rescue oxycodone. Patients in the tramadol-paracetamol group had more adverse events associated with analgesics during the first postoperative week (relative risk = 1.8, 95% confidence interval, 1.2-2.6). CONCLUSION: Add-on pain treatment with tramadol-paracetamol did not enhance patients' satisfaction with early pain management after back surgery.

Effectiveness and safety of prehospital analgesia with nalbuphine and paracetamol versus morphine by paramedics - an observational study.

BACKGROUND: Despite the development of various analgesic concepts, prehospital oligoanalgesia remains very common. The present work examines prehospital analgesia by paramedics using morphine vs. nalbuphine + paracetamol. METHODS: Patients with out-of-hospital-analgesia performed by paramedics from the emergency medical services of the districts of Fulda (morphine) and Gütersloh (nalbuphine + paracetamol) were evaluated with regards to pain intensity at the beginning and the end of prehospital treatment using the Numeric-Rating-Scale for pain (NRS), sex, age, and complications. The primary endpoint was achievement of adequate analgesia, defined as NRS < 4 at hospital handover, depending on the analgesics administered (nalbuphine + paracetamol vs. morphine). Pain intensity before and after receiving analgesia using the NRS, sex, age and complications were also monitored. RESULTS: A total of 1,808 patients who received out-of-hospital-analgesia were evaluated (nalbuphine + paracetamol: 1,635 (90.4%), NRS-initial: 8.0 ± 1.4, NRS-at-handover: 3.7 ± 2.0; morphine: 173(9.6%), NRS-initial: 8.5 ± 1.1, NRS-at-handover: 5.1 ± 2.0). Factors influencing the difference in NRS were: initial pain intensity on the NRS (regression coefficient (RK): 0.7276, 95%CI: 0.6602-0.7950, p < 0.001), therapy with morphine vs. nalbuphine + paracetamol (RK: -1.2594, 95%CI: -1.5770 - -0.9418, p < 0.001) and traumatic vs. non-traumatic causes of pain (RK: -0.2952, 95%CI: -0.4879 - -0.1024, p = 0.002). Therapy with morphine (n = 34 (19.6%)) compared to nalbuphine + paracetamol (n = 796 (48.7%)) (odds ratio (OR): 0.274, 95%CI: 0.185-0.405, p < 0.001) and the initial NRS score (OR:0.827, 95%CI: 0.771-0.887, p < 0.001) reduced the odds of having an NRS < 4 at hospital handover. Complications occurred with morphine in n = 10 (5.8%) and with nalbuphine + paracetamol in n = 35 (2.1%) cases. Risk factors for complications were analgesia with morphine (OR: 2.690, 95%CI: 1.287-5.621, p = 0.008), female sex (OR: 2.024, 95%CI: 1.040-3.937, p = 0.0379), as well as age (OR: 1.018, 95%CI: 1.003-1.034, p = 0.02). CONCLUSIONS: Compared to morphine, prehospital analgesia with nalbuphine + paracetamol yields favourable effects in terms of analgesic effectiveness and a lower rate of complications and should therefore be considered in future recommendations for prehospital analgesia.

Intermittent intravenous paracetamol versus continuous morphine in infants undergoing cardiothoracic surgery: a multi-center randomized controlled trial.

BACKGROUND: To determine whether intermittent intravenous (IV) paracetamol as primary analgesic would significantly reduce morphine consumption in children aged 0-3 years after cardiac surgery with cardiopulmonary bypass. METHODS: Multi-center, randomized, double-blinded, controlled trial in four level-3 Pediatric Intensive Care Units (PICU) in the Netherlands and Belgium. Inclusion period; March 2016-July 2020. Children aged 0-3 years, undergoing cardiac surgery with cardiopulmonary bypass were eligible. Patients were randomized to continuous morphine or intermittent IV paracetamol as primary analgesic after a loading dose of 100 mcg/kg morphine was administered at the end of surgery. Rescue morphine was given if numeric rating scale (NRS) pain scores exceeded predetermined cutoff values. Primary outcome was median weight-adjusted cumulative morphine dose in mcg/kg in the first 48 h postoperative. For the comparison of the primary outcome between groups, the nonparametric Van Elteren test with stratification by center was used. For comparison of the proportion of patients with one or more NRS pain scores of 4 and higher between the two groups, a non-inferiority analysis was performed using a non-inferiority margin of 20%. RESULTS: In total, 828 were screened and finally 208 patients were included; parents of 315 patients did not give consent and 305 were excluded for various reasons. Fourteen of the enrolled 208 children were withdrawn from the study before start of study medication leaving 194 patients for final analysis. One hundred and two patients received intermittent IV paracetamol, 106 received continuous morphine. The median weight-adjusted cumulative morphine consumption in the first 48 h postoperative in the IV paracetamol group was 5 times lower (79%) than that in the morphine group (median, 145.0 (IQR, 115.0-432.5) mcg/kg vs 692.6 (IQR, 532.7-856.1) mcg/kg; P < 0.001). The rescue morphine consumption was similar between the groups (p = 0.38). Non-inferiority of IV paracetamol administration in terms of NRS pain scores was proven; difference in proportion - 3.1% (95% CI - 16.6-10.3%). CONCLUSIONS: In children aged 0-3 years undergoing cardiac surgery, use of intermittent IV paracetamol reduces the median weight-adjusted cumulative morphine consumption in the first 48 h after surgery by 79% with equal pain relief showing equipoise for IV paracetamol as primary analgesic. Trial Registration Clinicaltrials.gov, Identifier: NCT05853263; EudraCT Number: 2015-001835-20.

Fixed-time interval vs on-demand oral analgesia after vaginal delivery: a randomized controlled trial.

BACKGROUND: Scheduled administration of analgesics was proven superior to on-demand dosing following cesarean deliveries. However, this protocol was not compared after vaginal delivery. OBJECTIVE: To compare the efficacy of a fixed- vs on-demand analgesic protocol for the management of pain in the first 24 hours after a vaginal delivery. STUDY DESIGN: This randomized, prospective, controlled trial was conducted at a single tertiary medical center between June 1, 2020 and June 30, 2022. Vaginally delivered patients were randomly assigned to receive oral analgesics (paracetamol 1 g + ibuprofen 400 mg) either every 6 hours for the first 24 hours postpartum (scheduled analgesia group) or as needed (on-demand group). Pain level during the first 24 hours postdelivery was measured using a 10-point visual analog scale. RESULTS: A total of 200 patients were randomized 1:1 to the 2 cohorts. Baseline and delivery characteristics, including oxytocin augmentation, epidural anesthesia, episiotomy rate, and neonatal birthweight, were comparable between groups. Patients in the scheduled group received more paracetamol and ibuprofen doses in the first 24 hours (2.9±1.3 and 2.9±1.2 doses vs 0.8±1.1 and 0.7±1.1 doses, respectively; P<.001). Pain score was comparable between study groups (5.31±1.92 vs 5.29±1.67; P=.626) even after subanalysis for primiparity, episiotomy, and vacuum-assisted delivery (P>.05). However, patients on a fixed treatment schedule were more likely to breastfeed their baby (98% vs 88%; P=.006) as than those receiving treatment on demand. In addition, they were more satisfied with their labor and delivery experience, as evaluated by Birth Satisfaction Scale questionnaires quality control (37.9±4.7 vs 31.1±5.2; P=.0324), patient attributes (35.0±5.1 vs 30.3±6.3; P=.0453), and stress experienced (58.1±8.5 vs 50.1±8.3; P=.0398). No side effects or adverse outcomes were reported in either group. CONCLUSION: A scheduled analgesic protocol for postpartum pain management following vaginal delivery revealed similar pain scores compared with an on-demand protocol, although it was associated with higher breastfeeding rates and higher maternal satisfaction.

Effect of an intravenous acetaminophen/ibuprofen fixed-dose combination on postoperative opioid consumption and pain after video-assisted thoracic surgery: a double-blind randomized controlled trial.

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) often induces significant postoperative pain, potentially leading to chronic pain and decreased quality of life. This study aimed to evaluate the acetaminophen/ibuprofen combination effectiveness in reducing analgesic requirements and pain intensity in patients undergoing VATS. STUDY DESIGN: This is a double-blinded randomized controlled trial. METHODS: Adult patients scheduled for elective VATS for lung resection were randomized to receive either intravenous acetaminophen and ibuprofen (intervention group) or 100 mL normal saline (control group). Treatments were administered post-anesthesia induction and every 6 h for three cycles. The primary outcome was total analgesic consumption at 24 h postoperatively. Secondary outcomes were cumulative analgesic consumption at 2 and 48 h; analgesic-related side effects at 2, 24, and 48 h; quality of recovery at 24 h and 48 h postoperatively; pain intensity at rest and during coughing; and rescue analgesics use. Chronic postsurgical pain (CPSP) was assessed through telephone interviews 3 months postoperatively. RESULTS: The study included 96 participants. The intervention group showed significantly lower analgesic consumption at 24 h and 48 h postoperatively (24 h: median difference: - 100 µg equivalent intravenous fentanyl [95% confidence interval (CI) - 200 to - 5 µg], P = 0.037; 48 h: median difference: - 140 µg [95% CI - 320 to - 20 µg], P = 0.035). Compared to the controls, the intervention group exhibited a significantly lower quality of recovery 24 h post-surgery, with no significant difference at 48 h. All pain scores except for coughing at 48 h post-surgery were significantly lower in the intervention group compared to the controls. No significant differences were observed between the groups in postoperative nausea and vomiting occurrence, hospital stay length, and CPSP. CONCLUSION: Perioperative administration of acetaminophen/ibuprofen significantly decreased analgesic needs in patients undergoing VATS, providing an effective postoperative pain management strategy, and potentially minimizing the need for stronger analgesics.

Robotic-assisted hysterectomy for benign gynecologic disease in the United States: in-hospital use of opioid and non-opioid analgesics.

To compare the in-hospital opioid and non-opioid analgesic use among women who underwent robotic-assisted hysterectomy (RH) vs. open (OH), vaginal (VH), or laparoscopic hysterectomy (LH). Records of women in the United States who underwent hysterectomy for benign gynecologic disease were extracted from the Premier Healthcare Database (2013-2019). Propensity score methods were used to create three 1:1 matched cohorts stratified in inpatients [RH vs. OH (N = 16,821 pairs), RH vs. VH (N = 6149), RH vs. LH (N = 11,250)] and outpatients [RH vs. OH (N = 3139), RH vs. VH (N = 29,954), RH vs. LH (N = 85,040)]. Opioid doses were converted to morphine milligram equivalents (MME). Within matched cohorts, opioid and non-opioid analgesic use was compared. On the day of surgery, the percentage of patients who received opioids differed only for outpatients who underwent RH vs. LH or VH (maximum difference = 1%; p < 0.001). RH was associated with lower total doses of opioids in all matched cohorts (each p < 0.001), with the largest difference observed between RH and OH: median (IQR) of 47.5 (25.0-90.0) vs. 82.5 (36.0-137.0) MME among inpatients and 39.3 (19.5-66.0) vs. 60.0 (35.0-113.3) among outpatients. After the day of surgery, fewer inpatients who underwent RH received opioids vs. OH (78.7 vs. 87.5%; p < 0.001) or LH (78.6 vs. 80.6%; p < 0.001). The median MME was lower for RH (15.0; 7.5-33.5) versus OH (22.5; 15.0-55.0; p < 0.001). Minor differences were observed for non-opioid analgesics. RH was associated with lower in-hospital opioid use than OH, whereas the same magnitude of difference was not observed for RH vs. LH or VH.

Clinical validation of a fast-acting acetaminophen: a randomized, active and placebo controlled dental pain study.

OBJECTIVES: To address the need for faster pain relief of over-the-counter (OTC) analgesic users, a novel drug delivery technology was developed to achieve faster absorption of orally administered acetaminophen with the goal of delivering earlier onset of pain relief. Previous development studies suggested that a 1000 mg dose of this fast-acting acetaminophen (FA-acetaminophen) formulation provided faster absorption and onset of action versus, commercially available OTC fast-acting analgesics, 1000 mg of extra-strength acetaminophen (ES-acetaminophen) or 400 mg of liquid-filled ibuprofen capsules (LG-ibuprofen). This study was designed as the definitive trial evaluating the onset of pain relief of FA-acetaminophen versus these same OTC comparators. METHODS: This single-dose, randomized, double-blind, placebo- and active-controlled clinical trial compared analgesic onset, overall efficacy, and safety of FA-acetaminophen 1000 mg, ES-acetaminophen 1000 mg, LG-ibuprofen 400 mg, and placebo over 4 h in a postsurgical dental pain model. Following removal of 3 to 4 impacted third molars, 664 subjects with moderate-to-severe pain were randomized in a 4:4:2:1 ratio to FA-acetaminophen (249), ES-acetaminophen (232), LG-ibuprofen (124), or placebo (59). Mean age was 18.9 years; 45.5% were male; 57.5% had severe baseline pain intensity. Subjects stopped a first stopwatch if/when they had perceptible pain relief and a second stopwatch if/when their pain relief became meaningful to them. Pain intensity difference (PID) and pain relief (PAR) were obtained using an 11-point numerical rating scale. FINDINGS: FA-acetaminophen 1000 mg had faster median time to onset of pain relief (15.7 min) compared to ES-acetaminophen 1000 mg (20.2 min, p = 0.035), LG-ibuprofen 400 mg (23.2 min, p < 0.001), and placebo (non-estimable), statistically greater mean PAR and PID scores than other treatment groups at 15 and 30 min, and a statistically greater percentage of subjects with confirmed perceptible pain relief at 15 and 20 min. At 25 min, FA-acetaminophen 1000 mg had a statistically significantly greater percentage of subjects with confirmed perceptible pain relief than LG-ibuprofen 400 mg and placebo. No clinically significant adverse events were reported. CONCLUSIONS: This study supports previous studies, demonstrating faster onset of analgesia with FA-acetaminophen 1000 mg compared to OTC ES-acetaminophen 1000 mg and OTC LG-ibuprofen 400 mg. CLINICALTRIALS.GOV IDENTIFIER: NCT03224403 https://clinicaltrials.gov/ct2/show/NCT03224403.

Pain management after total hip arthroplasty: comparative study of analgesic efficacy and tolerability between oral tramadol/dexketoprofen and injectable paracetamol + tramadol.

BACKGROUND: Multimodal analgesia for total hip arthroplasty (THA) is increasingly employed to reduce early postoperative pain and promote fast patient discharge. The aim of this study was to compare the efficacy and tolerability of tramadol/dexketoprofen (TRAM/DKP, Group A) versus paracetamol + tramadol (PARA+TRAM, Group B) in patients undergoing THA using minimally invasive direct anterior approach (DAA). METHODS: A single-centre, randomised, single-blind, parallel, interventional study conducted in 323 patients undergoing primary THA with DAA was performed. Group A consisted of 188 patients and Group B of 135. The primary endpoints were the change from baseline (measured 2 hours postoperatively) in pain intensity (PI) during the treatment period (48 hours), assessed by visual analogue scale (VAS) at pre-specified postoperative time-points (2, 8, 24, 48 hours) and the total rescue medication (RM) use during the first 24 hours postoperatively. RESULTS: As early as 2 hours after baseline, Group A showed a greater PI reduction from baseline compared to Group B (-26.24% vs. -6.87%; p < 0.001). A lower mean PI (VAS) score was consistently found over the entire observation period following treatment with TRAM/DKP than with PARA+TRAM as well as more than 2-fold higher proportion of responders at the end of treatment period. More patients in Group B required RM in comparison to those in Group A (15.6% vs. 3.7%, p < 0.001). Both treatments were well tolerated. CONCLUSIONS: After THA, oral TRAM/DKP provides faster and greater pain relief when compared to intravenous PARA+TRAM with limited consumption of RM and favourable tolerability profile. Our study expands the use of TRAM/DKP in the setting of major orthopaedic surgeries. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov (NCT04178109).

Paracetamol and ibuprofen combination for the management of acute mild-to-moderate pain in children: expert consensus using the Nominal Group Technique (NGT).

BACKGROUND: Acute pain is a common symptom in children of all ages, and is associated with a variety of conditions. Despite the availability of guidelines, pain often remains underestimated and undertreated. Paracetamol and ibuprofen are the most commonly used drugs for analgesia in Pediatrics. Multimodal pain management by using a combination of paracetamol and ibuprofen results in greater analgesia. METHODS: An investigation using the Nominal Group Technique was carried out between May and August 2022. Two open (non-anonymous) questionnaires were consecutively sent to a Board of ten clinicians to understand their opinions on the use of the oral paracetamol and ibuprofen association. Answers were examined in a final meeting where conclusions were drawn. RESULTS: The board achieved a final consensus on a better analgesic power of paracetamol and ibuprofen in fixed-dose combination as compared to monotherapy, without compromising safety. Strong consensus was reached on the opinion that the fixed-dose combination of paracetamol and ibuprofen may be a useful option in case of inefficacy of one or other drug as monotherapy, especially in case of headaches, odontalgia, earache, and musculoskeletal pain. The use of the fixed combination may be also considered suitable for postoperative pain management. CONCLUSIONS: The use of the fixed-dose combination may represent advantage in terms of efficacy and safety, allowing a better control of the dose of both paracetamol and ibuprofen as monotherapy, thus minimizing the risk of incorrect dosage. However, the limited evidence available highlights the need for future well designed studies to better define the advantages of this formulation in the various therapeutic areas.

Anestesia libre de opioides para cistectomía radical laparotómica en obesidad mórbida / Opioid-free anesthesia for open radical cystectomy in morbid obesity

El estudio de la técnica anestésica libre de opioides aporta evidencias de su efectividad y seguridad. Sin embargo, aún no están bien definidos todos sus riesgos y beneficios, ni en qué pacientes o intervenciones puede ser superior a la técnica anestésica convencional basada en opioides. Las cirugías intensivas y/o duraderas plantean dudas para la utilización de esta técnica por la respuesta a cambios hemodinámicos bruscos, al no producir la simpaticolisis a través de la actuación sobre el receptor μ y haber poca experiencia de uso. Una paciente con obesidad mórbida fue sometida a cistectomía radical con derivación urinaria tipo Bricker mediante laparotomía infraumbilical, consiguiéndose una adecuada estabilidad hemodinámica y una analgesia óptima en el postoperatorio sin emplear opioides intraoperatorios. La anestesia libre de opioides está en expansión con una evidencia creciente. No obstante, es necesario seguir investigando sobre sus posibilidades de utilización, las distintas combinaciones de fármacos que se puedan emplear y la resolución de complicaciones que puedan ocurrir.(AU)

Opioid-free anaesthesia shows evidence about its efectivity and security, even though its risks and benefits are not well defined. Neither are the patient profile or sort of surgery where it could be superior to the conventional opioid-based anaesthetic technique. Aggressive and/or long-lasting surgeries set out several queries on this technique regarding sudden hemodynamic changes, as it does not produce sympatholysis through μ receptor and there is modest experience in this technique. A morbidly obese patient received open radical cystectomy with Bricker-type urinary diversion using infraumbilical incision under OFA protocol, maintaining an adequate hemodynamic stability and excellent analgesia in postoperatory care without using any intraoperative opioids. Opioid-free anaesthesia technique is developing its evidence. However, it is necessary to keep on researching its clinical applications, different drug combinations and solutions to its expected complications.(AU)

Metabolomic Evaluation of N-Acetyl-p-Benzoquinone Imine Protein Adduct Formation with Therapeutic Acetaminophen Administration: Sex-based Physiologic Differences.

BACKGROUND: Acetaminophen (APAP)-associated transaminase elevation, induced by N-acetyl-p-benzoquinone imine (NAPQI) protein adduction, remains an area of research interest. Distinct from known genetic, physiologic, and dosage associations dictating severity of hepatic injury, no known factors predict an absence of protein adduct formation at therapeutic APAP dosing. HYPOTHESIS: Sex-based physiology is predictive of APAP-induced protein adduct formation and differential metabolite expression at therapeutic doses. METHODS: This retrospective study interrogated serum samples collected for a prior study investigating fluctuations of alanine aminotransferase (ALT) over time with 4G daily APAP dosing for ≥ 16 days in subjects from Denver, Colorado. Subjects were grouped by adduct formation (n = 184) vs no adducts (n = 20). Samples were run on ultra-high-performance liquid chromatography mass spectrometry from study days 0, 7, 16, and 31. Significant metabolite expressions were identified using t-tests with false discovery rate correction (FDR), partial least squares discriminant, and ANOVA simultaneous comparison analyses. Demographic and clinical data were explored using t-tests with FDR (age, weight, BMI, ALT) and Chi-square (sex, ethnicity, race) analyses. RESULTS: In pre-treatment samples, relative quantitation caprylic acid was expressed ninefold higher and 6-carboxyhexanoate was expressed threefold lower in subjects who did not develop adducts. Lactate had greater expression in the no adducts group (p = 0.001). Using absolute quantitation, glutathione was expressed 2.6-fold greater among no adduct subjects. Odds of males developing NAPQI protein adducts at therapeutic APAP dosing were 5.91 times lower than females (95% CI = 2.3-14.9; p = 0.0001). CONCLUSION: Multiple metabolites were differentially expressed based on adduct group and sex. Metabolites were identified unique to adduct development independent of sex. At therapeutic APAP dosing, males were less likely to develop APAP protein adducts. Further research into lipid biosynthesis and metabolism may provide further insight into physiology associated with adduct production.

Dexmedetomidine Combined with Femoral Nerve Block Provides Effective Analgesia Similar to Femoral Nerve Combined with Sciatic Nerve Block in Patients Undergoing Total Knee Arthroplasty: A Randomized Controlled Study.

BACKGROUND: Total knee arthroplasty (TKA) is a severe traumatic procedure, and femoral nerve block (FNB) combined with a sciatic nerve block (SNB) is widely used in TKA. However, injury of the sciatic nerve is clinically reported. Dexmedetomidine (DEX) could reduce stress and inflammation, as well as improve pain in TKA. This study aims to observe the analgesic impact of DEX combined with FNB in TKA. METHODS: Eighty-eight patients undergoing TKA were included and randomly divided into two groups: DF group (FNB combined with DEX 0.6µg/kg before surgery, followed by DEX 0.2-0.4µg/kg/h until articular closure) and SF group (FNB combined with SNB). Each nerve was blocked with 0.375% ropivacaine 20mL, and all patients received general anesthesia routinely. The primary endpoint was the pain visual analog scale (VAS) score during activities at postoperative 24 hours. RESULTS: There was no statistical difference in the pain VAS scores at any time point. The mean duration of analgesia for patients with rescue analgesic requests was comparable between the two groups: 25.4 ± 6.3 hours in the DF group vs 24.8 ± 6.4 hours in the SF group (two-sample t-test, p=0.738). The total dose of sufentanil was similar between groups (P=0.355). The maintenance dose of propofol and dose of rescue analgesics were comparable (all P>0.05). There were no statistical differences in the incidence of adverse events. However, the time to extubate in the DF group was significantly longer than those in the SF group (P<0.001). CONCLUSION: DEX combined with FNB could provide effective analgesia similar to SNB combined with FNB in TKA. CLINICAL TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on November 17, 2019 (identifier: ChiCTR1900027552).

Short-Term Safety of Repeated Acetaminophen Use in Patients With Compensated Cirrhosis.

Current guidelines recommend restricting acetaminophen (APAP) use in patients with cirrhosis, but evidence to support that recommendation is lacking. Prior studies focused on pharmacokinetics (PK) of APAP in cirrhosis but did not rigorously examine clinical outcomes, sensitive biomarkers of liver damage, or serum APAP-protein adducts, which are a specific marker of toxic bioactivation. Hence, the goal of this pilot study was to test the effects of regularly scheduled APAP dosing in a well-defined compensated cirrhosis group compared to control subjects without cirrhosis, using the abovementioned outcomes. After a 2-week washout, 12 subjects with and 12 subjects without cirrhosis received 650 mg APAP twice per day (1.3 g/day) for 4 days, followed by 650 mg on the morning of day 5. Patients were assessed in-person at study initiation (day 1) and on days 3 and 5. APAP-protein adducts and both conventional (alanine aminotransferase) and sensitive (glutamate dehydrogenase [GLDH], full-length keratin 18 [K18], and total high-mobility group box 1 protein) biomarkers of liver injury were measured in serum on the mornings of days 1, 3, and 5, with detailed PK analysis of APAP, metabolites, and APAP-protein adducts throughout day 5. No subject experienced adverse clinical outcomes. GLDH and K18 were significantly different at baseline but did not change in either group during APAP administration. In contrast, clearance of APAP-protein adducts was dramatically delayed in the cirrhosis group. Minor differences for other APAP metabolites were also detected. Conclusion: Short-term administration of low-dose APAP (650 mg twice per day, <1 week) is likely safe in patients with compensated cirrhosis. These data provide a foundation for future studies to test higher doses, longer treatment, and subjects who are decompensated, especially in light of the remarkably delayed adduct clearance in subjects with cirrhosis.

Effect of Acetaminophen use during pregnancy on adverse pregnancy outcomes: a systematic review and meta-analysis.

INTRODUCTION: A high number of women are exposed to acetaminophen during pregnancy worldwide. This drug safety during pregnancy regarding preterm birth, birth weight, and fetal development has not been well described. This study investigated the effect of acetaminophen use during pregnancy on selected adverse pregnancy outcomes. AREAS COVERED: Databases were searched to identify studies reporting the effects of acetaminophen use during pregnancy on preterm birth, low birth weight, and small for gestational age. The studies' quality was assessed by the Newcastle-Ottawa Scale and the Methodological Index for Non-Randomized Studies. Risk ratios with 95% confidence intervals were estimated using a fixed or random-effects model. Six studies were included for final review, four cohort and two case-control studies. We found no increased risk of preterm birth (RR 0.97; 95% CI 0.59-1.58), and decreased risks of low birth weight (RR 0.65; 95% CI 0.59-0.72) and small for gestational age (RR 0.69; 95% CI 0.50-0.97). Acetaminophen exposure during the third trimester revealed non-significantly in the outcomes. EXPERT OPINION: Exposure to acetaminophen during pregnancy appears to not increase the risk of the outcomes analyzed. However, there is a lack of information regarding the exposure dose and frequency of acetaminophen use.

Perioperative Buprenorphine Management: A Multidisciplinary Approach.

Buprenorphine formulations (including buprenorphine/naloxone) are effective treatments of pain and opioid use disorder (OUD). Historically, perioperative management of patients prescribed buprenorphine involved abstinence from buprenorphine sufficient to allow for unrestricted mu-opioid receptor availability to full agonist opioid (FAO) treatment. Evidence is mounting that a multimodal analgesic strategy, including simultaneous administration of buprenorphine and FAO, nonopioid adjuncts such as acetaminophen and nonsteroidal anti-inflammatory drugs, and regional anesthesia, is a safe and effective perioperative strategy for the patient prescribed long-term buprenorphine treatment of OUD. This strategy will likely simplify management and more seamlessly provide continuous buprenorphine treatment of OUD after hospital discharge.

Dexmedetomidine Clearance Decreases with Increasing Drug Exposure: Implications for Current Dosing Regimens and Target-controlled Infusion Models Assuming Linear Pharmacokinetics.

BACKGROUND: Numerous pharmacokinetic models have been published aiming at more accurate and safer dosing of dexmedetomidine. The vast majority of the developed models underpredict the measured plasma concentrations with respect to the target concentration, especially at plasma concentrations higher than those used in the original studies. The aim of this article was to develop a dexmedetomidine pharmacokinetic model in healthy adults emphasizing linear versus nonlinear kinetics. METHODS: The data of two previously published clinical trials with stepwise increasing dexmedetomidine target-controlled infusion were pooled to build a pharmacokinetic model using the NONMEM software package (ICON Development Solutions, USA). Data from 48 healthy subjects, included in a stratified manner, were utilized to build the model. RESULTS: A three-compartment mamillary model with nonlinear elimination from the central compartment was superior to a model assuming linear pharmacokinetics. Covariates included in the final model were age, sex, and total body weight. Cardiac output did not explain between-subject or within-subject variability in dexmedetomidine clearance. The results of a simulation study based on the final model showed that at concentrations up to 2 ng · ml-1, the predicted dexmedetomidine plasma concentrations were similar between the currently available Hannivoort model assuming linear pharmacokinetics and the nonlinear model developed in this study. At higher simulated plasma concentrations, exposure increased nonlinearly with target concentration due to the decreasing dexmedetomidine clearance with increasing plasma concentrations. Simulations also show that currently approved dosing regimens in the intensive care unit may potentially lead to higher-than-expected dexmedetomidine plasma concentrations. CONCLUSIONS: This study developed a nonlinear three-compartment pharmacokinetic model that accurately described dexmedetomidine plasma concentrations. Dexmedetomidine may be safely administered up to target-controlled infusion targets under 2 ng · ml-1 using the Hannivoort model, which assumed linear pharmacokinetics. Consideration should be taken during long-term administration and during an initial loading dose when following the dosing strategies of the current guidelines.

Dexmedetomidine Alleviates Gut-Vascular Barrier Damage and Distant Hepatic Injury Following Intestinal Ischemia/Reperfusion Injury in Mice.

BACKGROUND: Intestinal ischemia/reperfusion (I/R) challenge often results in gut barrier dysfunction and induces distant organ injury. Dexmedetomidine has been shown to protect intestinal epithelial barrier against I/R attack. The present study aims to investigate the degree to which intestinal I/R attack will contribute to gut-vascular barrier (GVB) damage, and to examine the ability of dexmedetomidine to minimize GVB and liver injuries in mice. METHODS: In vivo, intestinal ischemic challenge was induced in mice by clamping the superior mesenteric artery for 45 minutes. After clamping, the mice were subjected to reperfusion for either 2, 4, 6, or 12 hours. Intraperitoneal injection of dexmedetomidine 15, 20, or 25 µg·kg-1 was performed intermittently at the phase of reperfusion. For the in vitro experiments, the challenge of oxygen-glucose deprivation/reoxygenation (OGD/R) was established in cultured vascular endothelial cells, and dexmedetomidine (1 nM) was used to treat the cells for 24 hours. Moreover, in vivo and in vitro, SKL2001 (a specific agonist of ß-catenin) or XAV939 (a specific inhibitor of ß-catenin) was applied to determine the role of ß-catenin in the impacts provided by dexmedetomidine. RESULTS: The attack of intestinal I/R induced GVB damage. The greatest level of damage was observed at 4 hours after intestinal reperfusion. There was a significant increase in plasmalemma vesicle-associated protein-1 (PV1, a specific biomarker for endothelial permeability) expression (5.477 ± 0.718 vs 1.000 ± 0.149; P < .001), and increased translocation of intestinal macromolecules and bacteria to blood and liver tissues was detected (all P < .001). Liver damages were observed. There were significant increases in histopathological scores, serum parameters, and inflammatory factors (all P < .001). Dexmedetomidine 20 µg·kg-1 reduced PV1 expression (0.466 ± 0.072 vs 1.000 ± 0.098; P < .001) and subsequent liver damages (all P < .01). In vitro, dexmedetomidine significantly improved vascular endothelial cell survival (79.387 ± 6.447% vs 50.535 ± 1.766%; P < .001) and increased the productions of tight junction protein and adherent junction protein (all P < .01) following OGD/R. Importantly, in cultured cells and in mice, ß-catenin expression significantly decreased (both P < .001) following challenge. Dexmedetomidine or SKL2001 upregulated ß-catenin expression and produced protective effects (all P < .01). However, XAV939 completely eliminated the protective effects of dexmedetomidine on GVB (all P < .001). CONCLUSIONS: The disruption of GVB occurred following intestinal I/R. Dexmedetomidine alleviated I/R-induced GVB impairment and subsequent liver damage.