Cervical Epidural Spinal Analgesia for Acute Management of Severe Unilateral Forelimb Lameness: Case Report

A 20-year-old Quarter Horse gelding was presented with severe right forelimb lameness (5/5 AAEP Lameness Scale) due to a tear of the superficial digital flexor muscle which was diagnosed via palpation of swelling and ultrasonography revealing major muscle fiber disruption and hematoma formation. When traditional systemic therapy (non-Steroidal anti-inflammatories) did not restore clinically acceptable comfort and the risk of supporting limb laminitis became a reasonable concern, a cervical epidural catheter was placed between the first and second cervical vertebrae in the standing, sedated patient using ultrasound guidance. The gelding was treated with epidural morphine (0.1 mg/kg every 24 h then decreased to 0.05 mg/kg every 12 h) and was pain-scored serially following treatment. Spinal analgesia was provided for 3 days. Pain scores significantly decreased following each treatment with morphine, and the gelding was successfully managed through the acutely painful period without any adverse effects associated with the C1-C2 epidural catheter placement technique, the epidural morphine, or contralateral limb laminitis. At the 2-month follow-up, the gelding was walking sound with no complications seen at the catheter insertion site. In this case, spinal analgesia using epidural morphine administered via a cervical epidural catheter was an effective and technically achievable option for pain management associated with severe forelimb muscle injury in a horse.

Epidural morphine in COVID ARDS patients with high respiratory drive: a structured summary of a study protocol for a randomised controlled trial

Objectives We aim to study the effect of epidural morphine as a means to reduce high respiratory drive in COVID 19 patients on non-invasive ventilation (NIV)—primary end point—and to study its effect on respiratory parameters, subjective patient comfort, rates of endotracheal intubation, duration of mechanical ventilation and mortality. Trial design Parallel group, randomised, double blind, single centre placebo control trial. Allocation ratio 1:1, superiority trial Participants Trial site and population—COVID ICU patients in the All India Institute of Medical Sciences (AIIMS) Bhubaneswar, Odisha, India Inclusion and exclusion criteria Inclusion criteria Adult patients on NIV with COVID-19 Exclusion criteria Metabolic acidosis HCO3-< 16 and pH < 7.2. Severe hypoxemia warranting cessation of NIV and intubation, non-acceptance of NIV and proven sepsis. Technical difficulty for epidural catheterization, coagulation abnormalities, low respiratory drive and EOL orders. Sources or methods of recruitment—daily discussion at 8 am of new admissions to COVID ICU on NIV—consenting adult patients with COVID19 on NIV and high respiratory drive; not meeting exclusion criteria will be recruited for the trial and randomised. Intervention and comparator Patients of both groups will be turned to a lateral or sitting position (as comfortable), and an injection of local anaesthetic be given at lumbar 2–3/3–4 space. In the intervention group, an epidural catheter will be inserted using aseptic technique and fixed to the skin. The control group will have a sham catheter fixed exactly like in the intervention group, but not entering the epidural space. The intervention group will be administered injection morphine sulphate once every 18–24 h into the epidural space. The doses will be escalated daily (5–10 mg), titrated to effect: escalation limited by hypoventilation resulting in respiratory acidosis (pH < 7.2). The intervention will continue for a minimum of 2 doses and a maximum of 5 doses (96 h) of morphine. It will be stopped if the epidural catheter gets dislodged before the second dose or the patient is weaned off non-invasive ventilation to high flow mask for a continuous period of 24 h or requires endotracheal intubation. The patient will be followed up till death or 28 days after ICU discharge. Main outcomes Primary outcome—diaphragm thickening index fraction (average of minimum 3 readings) Secondary outcomes—ventilator parameters, sedation and pain scores, subjective comfort and dyspnoea scores, time to intubation, length of stay on NIV and 28-day mortality Timing of outcome assessment—every 8th hour assessment for 24 h after the last dose of epidural morphine or 120 h whichever is greater Randomisation A central random number list will be kept with the study research assistant. She will randomise according to the numbers available in the list using an allocation ratio of 1:1. An opaque sealed envelope concealing the allotted randomisation code will be dispatched to the ICU team. Blinding (masking) The assessor, patient, nurses and physicians will be blind to group allocation. One member of the team not involved in research will administer the intervention. Numbers to be randomised (sample size) Twenty-five patients per group; 50 patients total Trial status Protocol version 1. Not recruiting yet. Recruitment to begin by 24 July 2021 and end by 31 August 2022 Trial registration Central Trials Registry India CTRI CTRI/2021/07/035093. Registered on 23 July 2021. Prospectively registered Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol

Pruritus after continuous administration of epidural morphine for post-cesarean delivery analgesia: a case control study

Background Pruritus is one of the most common side effects of epidural morphine administered for post-surgery analgesia, and pregnant women tend to be highly susceptible. The relative contributions of morphine concentration, local anesthetics, and level of pain to pruritus after epidural morphine for post-cesarean delivery analgesia remain unclear. Accordingly, the present study aimed to identify risk factors for pruritus after continuous administration of epidural morphine for post-cesarean delivery analgesia. Methods This case control study was based on routinely collected clinical data. Participants included women who had undergone cesarean section and adopted a patient-controlled analgesia pump for postoperative analgesia. A series of logistic regression analyses were performed. Interaction terms were added to explore the moderation effects of combined local anesthetics and pain level on associations between morphine concentration and pruritus. Robustness of the results was checked through sensitivity analysis using propensity scores matching approach. Results Higher morphine concentration, assisted reproductive treatment, and multipara and cesarean section history were significantly more prevalent in the pruritus group than in the control group. The probabilities of pruritus at morphine concentrations of 10, 15, 20, 25, 30 and 40 μg/mL increased sequentially from 0.05, 0.1, 0.2, 0.35, 0.54 to 0.84, respectively. The trend remained steep in the ropivacaine stratum and became flatter when combined with levobupivacaine. At mild pain combined with levobupivacaine, the incidence of pruritus increased from 0.33 (95% confidence interval [CI] 0.1–0.68) in the 10 μg/mL morphine group to 0.48 (95% CI 0.1–0.88) in the 40 μg/mL morphine group. In the stratum of moderate pain combined with levobupivacaine, the incidence increased from 0.4 (95% CI 0.04–0.92) to 0.56 (95% CI 0.03–0.98). The results in the sensitivity analysis were in consistent with above findings. Conclusions Higher concentrations of morphine, multipara, and assisted reproductive treatment were factors associated with a higher probability of pruritus. Pain level or combined local anesthetics could moderate the association between morphine concentration and pruritus.

Nalmefene relieves epidural morphine-caused pruritus following caesarean section: a randomized and placebo-controlled clinical trial

Background. Epidural morphine has an effective analgesic effect in cesarean section patients; however, a very common adverse effect caused by epidural morphine is pruritus, which is difficult to treat or prevent. Here, we aimed to investigate whether a μ-opioid antagonist with central and peripheral effects reduces morphine-induced pruritus. Methods. In this prospective randomized trial, eighty patients scheduled for an elective cesarean section under spinal aesthesia with 3 mg of epidural morphine were assigned into the nalmefene group (n=40) or placebo group (n=40). After delivery, either 50 μg of intravenous nalmefene hydrochloride (Nalmefene group) or an equivalent amount of normal saline (Placebo group) was administered to the patients. In the meantime, an assessment of a series of side effects such as pruritus, nausea, and pain was conducted at 2, 4, 8, 12, and 24h after epidural morphine administration. Results. All eighty participants completed this trial. The total incidence of pruritus in the first 24 hours following the section was reduced in IV nalmefene group compared with the placebo group (37.5% vs 65%, P=0.003). Moreover, IV nalmefene administration relieved the pruritus intensity, whereas the difference in the incidence of nausea and vomiting between the two groups was not significant. Besides, the nalmefene group displayed significantly higher pain scores at 8, 12 and 24h than the placebo group (all P<0.05). However, no significant difference in the percentage of patients with an analgesic treatment was found between the two groups (P=0.37). Conclusion. In this study, a single dose of 50 μg of IV nalmefene was found to decrease the overall severity and incidence of epidural morphine-induced pruritus, but cause no adverse effect on postoperative analgesia.