The aim of this study is to determine the onset time of rocuronium after administration of ephedrine 0.15 mg/kg in patients with age ≥ 80 years. The hypothesis of this study is that ephedrine 0.15 mg/kg provides a shorter onset time compared to placebo (saline).
Numbers of elderly patients requiring anesthesia and surgery are increasing, and as a group, elderly patients are at high risk of postoperative complications. Aging leads to a progressive impairment of organ function and a decline in physiologic reserve and in the elderly patient population, pharmacodynamics and pharmacokinetics of medications administered during anesthesia may be influenced by the age-related reduction in cardiac output, liver function and renal function. Also, the body composition changes with age and elderly have lower total body water and an increase in body fat. Neuromuscular blocking agents (NMBAs) are administered during anesthesia to facilitate tracheal intubation. However, in elderly patients onset time of standard doses of NMBAs are prolonged, and for 0.6 mg/kg of rocuronium it is prolonged by 50% when comparing elderly with younger adults (median 135 seconds vs 90 seconds). A prolonged onset time of rocuronium may result in prolonged time to tracheal intubation which aims to secure the patients airway and breathing during anesthesia and thereby prevents pulmonary aspiration and hypoxia. It is therefore relevant to investigate measures to reduce onset time of rocuronium in the elderly. Ephedrine administered in younger adults undergoing general anesthesia has reduced the onset time of rocuronium 0.6 mg/kg. The mechanism behind this is speculated to be an increase in cardiac output. It is possible to detect onset time of NMBAs with objective neuromuscular monitoring perioperatively by train-of-four (TOF) stimulation at the ulnar nerve. The effect of ephedrine on onset time of rocuronium has not been assessed in elderly patients above 80 years of age. The possible benefit of this trial is to investigate whether ephedrine 0.15 mg/kg reduces onset time of rocuronium 0.6 mg/kg in the elderly. This may result in a shorter time to tracheal intubation and also establish better intubating conditions. The results may help to detect the optimal method for administering rocuronium to facilitate tracheal intubation in elderly patients. The investigators hypothesize that ephedrine 0.15 mg/kg will provide a shorter onset time of rocuronium compared to placebo (saline).
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
TRIPLE
Enrollment
80
0.15 mg/kg during induction.
1 ml during induction.
Department of Anaesthesiology, Pain and Respiratory Support, Rigshospitalet Glostrup
Copenhagen, Denmark
Department of Anesthesia, Centre of Head and Orthopedics, 6013 Rigshospitalet
Copenhagen, Denmark
Onset time of rocuronium 0.6 mg/kg defined as the time from administration of rocuronium until TOF count of 0.
Onset time is determined by an investigator using a stop-watch.
Time frame: Within 1 hour
Intubating conditions assessed by The Intubation Difficulty Scale (IDS)
Tracheal intubation will be performed when TOF count is zero. The anesthesiologist or nurse anesthetist will be interviewed after intubation by the investigator, who will note a score for each variable and the initials of the operator in the CRF. The intubating conditions will be classified with "Degree of Difficulty" according to the IDS scale, where an IDS score of 0 translates to "Easy", a score of 0 \< IDS ≤ 5 translates to "Slight Difficulty" and 5 \< IDS translates to "Moderate to Major Difficulty". Impossible intubation is defined by infinity (IDS = ∞ ).
Time frame: Within 1 hour
Intubating conditions assessed by Fuchs-Buder scale
Tracheal intubation will be performed when TOF count is zero. The anesthesiologist or nurse anesthetist will be interviewed after intubation by the investigator, who will note a score for each variable and the initials of the operator in the CRF. All variables will be assessed as either excellent, good or poor. The intubating conditions will be classified as excellent if all qualities are excellent, good if all qualities are either excellent or good and poor if the presence of a single quality listed as poor.
Time frame: Within 1 hour
Occurrence of new cardiac arrythmia during induction of anaesthesia (<15 minutes after administration of ephedrine or saline)
Time frame: Within 15 minutes
Change in mean arterial blood pressure from before induction to immediately after intubation
Time frame: Within 1 hour
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time to TOF 0.9
Time frame: Within 4 hours