Stability of Drugs Stored in Helicopters for Use by Emergency Medical Services: A Prospective Observational Study.

STUDY OBJECTIVE: Drugs stored in rescue helicopters may be subject to extreme environmental conditions. The aim of this study was to measure whether drugs stored under the real-life conditions of a Swiss helicopter emergency medical service (HEMS) would retain their potency over the course of 1 year. METHODS: A prospective, longitudinal study measuring the temperature exposure and concentration of drugs stored on 2 rescue helicopters in Switzerland over 1 year. The study drugs included epinephrine, norepinephrine, amiodarone, midazolam, fentanyl, naloxone, rocuronium, etomidate, and ketamine. Temperatures were measured inside the medication storage bags and the crew cabins at 10-minute intervals. Drug stability was measured on a monthly basis over the course of 12 months using high-performance liquid chromatography. The medications were considered stable at a minimum remaining drug concentration of 90% of the label claim. RESULTS: Temperatures ranged from -1.2 °C to 38.1 °C (29.84 °F to 100.58 °F) inside the drug storage bags. Of all the temperature measurements inside the drug storage bags, 37% lay outside the recommended storage conditions. All drugs maintained a concentration above 90% of the label claim. The observation periods for rocuronium and etomidate were shortened to 7 months because of a supply shortage of reference samples. CONCLUSION: Drugs stored under the real-life conditions of Swiss HEMS are subjected to temperatures outside the manufacturer's approved storage requirements. Despite this, all drugs stored under these conditions remained stable throughout our study. Real-life stability testing could be a way to extend drug exchange intervals.

Interactions of the protease inhibitor, ritonavir, with common anesthesia drugs.

The protease inhibitor, ritonavir, is a strong inhibitor of CYP 3A. The drug is used for management of the human immunovirus and is currently part of an oral antiviral drug combination (nirmatrelvir-ritonavir) for the early treatment of SARS-2 COVID-19-positive patients aged 12 years and over who have recognized comorbidities. The CYP 3A enzyme system is responsible for clearance of numerous drugs used in anesthesia (e.g., alfentanil, fentanyl, methadone, rocuronium, bupivacaine, midazolam, ketamine). Ritonavir will have an impact on drug clearances that are dependent on ritonavir concentration, anesthesia drug intrinsic hepatic clearance, metabolic pathways, concentration-response relationship, and route of administration. Drugs with a steep concentration-response relationship (ketamine, midazolam, rocuronium) are mostly affected because small changes in concentration have major changes in effect response. An increase in midazolam concentration is observed after oral administration because CYP 3A in the gastrointestinal wall is inhibited, causing a large increase in relative bioavailability. Fentanyl infusion may be associated with a modest increase in plasma concentration and effect, but the large between subject variability of pharmacokinetic and pharmacodynamic concentration changes suggests it will have little impact on an individual patient, especially when used with adverse effect monitoring. It has been proposed that drugs that have no or only a small metabolic pathway involving the CYP 3A enzyme be used during anesthesia, for example, propofol, atracurium, remifentanil, and the volatile agents. That anesthesia approach denies children of drugs with considerable value. It is better that the inhibitory changes in clearance of these drugs are understood so that rational drug choices can be made to tailor drug use to the individual patient. Altered drug dose, anticipation of duration of effect, timing of administration, use of reversal agents and perioperative monitoring would better behoove children undergoing anesthesia.

Fixed dilated pupils in Covid-19 ARDS patients under rocuronium, reversed after discontinuation.

Neuromuscular Blockade Agents (NMBA) are used in the management of moderate and severe Acute Respiratory Distress Syndrome (ARDS) patients. They have never been reported to present Central Nervous System adverse reactions. Shortage of cis-atracurium during the pandemic, led to the use of rocuronium. We report three patients with Covid-19 ARDS, who presented bilateral dilated, non-reactive pupils, after continuous rocuronium infusion. Brain CT findings were unremarkable and transcranial doppler tracings did not suggest brain edema or hemorrhage. NMBA's discontinuation led to reversal of the pupillary dilation. We believe that impairment of Blood-Brain-Barrier, due to Covid-19, led rocuronium access into the Central Nervous System, leading to this adverse effect. Clinicians should be aware of this adverse reaction when managing patients with Covid-19 ARDS warranting NMBA use.

Rocuronium-Induced Dilated Nonreactive Pupils in a Patient With Coronavirus Disease 2019: A Case Report.

We report the clinical case of a patient with coronavirus disease 2019 (COVID-19) who had recently undergone neurosurgery and presented with dilated nonreactive pupils during continuous rocuronium infusion, which was reversible with the suspension of the drug. Both the neurosurgical procedure and possible disruption of the blood-brain barrier due to COVID-19 infection may have led to the action of rocuronium in the central nervous system (CNS). Thus, clinicians must remember that neuromuscular blocking agents (NMBAs) can cause dilated nonreactive pupils in patients with COVID-19.

Anesthetic and surgical management of tracheostomy in a patient with COVID-19.

OBJECTIVE: The ongoing pandemic coronavirus disease-2019 (COVID-19) infection causes severe respiratory dysfunction and has become an emergent issue for worldwide healthcare. Since COVID-19 spreads through contact and droplet infection routes, careful attention to infection control and surgical management is important to prevent cross-contamination of patients and medical staff. Tracheostomy is an effective method to treat severe respiratory dysfunction with prolonged respiratory management and should be performed as a high-risk procedure METHOD: The anesthetic and surgical considerations in this case involved difficult goals of the patient safety and the management of infection among health care workers. Our surgical procedure was developed based on the previous experiences of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). RESULTS: We described the management procedures for tracheostomy in a patient with COVID-19, including the anesthesia preparation, surgical procedures, required medical supplies (a N95 mask or powered air purifying respirator, goggles, face shield, cap, double gloves, and a water-resistant disposable gown), and appropriate consultation with an infection prevention team. CONCLUSION: Appropriate contact, airborne precautions, and sufficient use of muscle relaxants are essential for performing tracheostomy in a patient with COVID-19.