Efficacy comparison of intraperitoneal anaesthesia and post-operative analgesia regimens in laboratory rats.

INTRODUCTION: Effective and safe anesthesia for rodents has long been a leading concern among biomedical researchers. Intraperitoneal injection constitutes an alternative to inhalant anesthesia. PURPOSE: The aim of this study was to identify a safe, reliable, and effective anesthesia and postoperative analgesia protocol for laboratory rats exposed to painful procedures. MATERIAL AND METHODS: Twenty-seven female Wistar rats in an ongoing study that required surgery were randomized into groups for three different intraperitoneal anesthesia protocols and three different analgesia regimens. The anesthesia groups were (1) medetomidine + ketamine (MK), (2) ketamine + xylacine (KX), and (3) fentanyl + medetomidine (FM). Three analgesia groups were equally distributed among the anesthesia groups: (1) local mepivacaine + oral ibuprofen (MI), (2) oral tramadol + oral ibuprofen (TI), and (3) local tramadol + oral tramadol + + oral ibuprofen (TTI). A core was assigned to measure anesthesia (0-3) and analgesia (0-2) effectiveness; the lower the score, the more effective the treatment. RESULTS: The mean MK score was 0.44 versus 2.00 for FM and 2.33 for KX. Mean score for analgesia on the first postoperative day was TTI (4.66) TI (9.13), and MI (10.14). Mean score 48 hours after surgery was TTI (3.4), TI (6.71), and MI (9.5). These differences were statistically significant. CONCLUSION: MK was shown to be a reliable, safe, and effective method of anesthesia. The TTI analgesia regimen is strongly recommended in light of these results.

Impact of ketamine as an adjunct sedative in acute respiratory distress syndrome due to COVID-19 Pneumonia.

PURPOSE: Deep sedation is sometimes needed in acute respiratory distress syndrome. Ketamine is a sedative that has been shown to have analgesic and sedating properties without having a detrimental impact on hemodynamics. This pharmacological profile makes ketamine an attractive sedative, potentially reducing the necessity for other sedatives and vasopressors, but there are no studies evaluating its effect on these medications in patients requiring deep sedation for acute respiratory distress syndrome. MATERIALS AND METHODS: This is a retrospective, observational study in a single center, quaternary care hospital in southeast Texas. We looked at adults with COVID-19 requiring mechanical ventilation from March 2020 to September 2020. RESULTS: We found that patients had less propofol requirements at 72 h after ketamine initiation when compared to 24 h (median 34.2 vs 54.7 mg/kg, p = 0.003). Norepinephrine equivalents were also significantly lower at 48 h than 24 h after ketamine initiation (median 38 vs 62.8 mcg/kg, p = 0.028). There was an increase in hydromorphone infusion rates at all three time points after ketamine was introduced. CONCLUSIONS: In this cohort of patients with COVID-19 ARDS who required mechanical ventilation receiving ketamine we found propofol sparing effects and vasopressor requirements were reduced, while opioid infusions were not.

Resurgence of combined intravenous Ketamine and regional anesthesia in pediatric ocular surgery in COVID-19 pandemic.

PURPOSE: The current pandemic of COVID-19 has made airway procedures like intubation and extubation, potential sources of virus transmission among health care workers. The aim of this work was to study the safety profile of combined ketamine and regional anesthesia in pediatric ocular surgeries during the COVID-19 pandemic. METHODS: This prospective study included pediatric patients undergoing ocular surgery under general anesthesia from April to October 2020. Children were premedicated with oral midazolam (0.25-0.50 mg/kg) or intramuscular ketamine (7-10 mg/kg), ondensetron (0.1 mg/kg) and atropine (0.02 mg/kg). Anesthesia was achieved with intravenous ketamine (4-5 mg/kg) and local anesthesia (peribulbar block or local infiltration). The patient's vital signs were monitored. Serious complications and postoperative adverse reactions related to anesthesia were documented. RESULTS: A total of 55 children (62 eyes) were operated. Lid tear was the most common surgical procedure performed [n = 18 (32.7%)]. Dose of ketamine needed ranged from 30 to 120 mg (66.67 ± 30.45). No intubation or resuscitation was needed. Four children complained of nausea and two needed an additional dose of intravenous ondansetron due to vomiting in the post-operative period. Incidence of postoperative nausea and vomiting was not affected by age, duration of surgery or dose of ketamine used (P > 0.05). There was no correlation between increase in pulse and dose of ketamine. CONCLUSION: Combined ketamine and regional anesthesia is a safe and effective alternative to administer anesthesia in a child during ocular surgeries.

Repeated ketamine injections in synergy with antidepressants for treating refractory depression: A case showing 6-month improvement.

WHAT IS KNOWN AND OBJECTIVE: Some patients with refractory depression who fail to respond to rapid injection of standard-dose ketamine are injected with high doses, but the safety and efficacy of this practice are unclear. CASE DESCRIPTION: A 57-year-old woman with refractory depression whose symptoms did not improve after 20-seconds intravenous injection of 0.5 mg/kg ketamine went into remission following eight, 1-minute intravenous injections of 1 mg/kg ketamine delivered over a 4-week period. By 6-month follow-up, no significant adverse events had occurred and cognitive function had improved. WHAT IS NEW AND CONCLUSION: High-dose intravenous injections of ketamine may stably improve depressive symptoms and cognitive function in patients with refractory depression who do not respond to rapid intravenous injection of standard-dose ketamine. The high-dose treatment appears to be associated with only mild side effects.