Comparison of onset time, duration of action, and intubating conditions after cisatracurium 0.15 mg/kg in young and elderly patients

Introduction

Tracheal intubation during anesthesia can be facilitated by the neuromuscular blocking agent cisatracurium. However, limited data exists about onset time, duration of action and effect on intubating conditions in elderly patients above 80 years of age. We hypothesized that elderly patients would present a longer onset time and duration of action compared to younger adults.

Methods

This prospective observational study included 31 young (18–40 years) and 29 elderly (≥ 80 years) patients. Patients were given fentanyl 2 μg/kg and propofol 1.5–2.5 mg/kg for induction of anesthesia and maintained with remifentanil and propofol. Monitoring of neuromuscular function was performed with acceleromyography. Primary outcome was onset time defined as time from injection of cisatracurium 0.15 mg/kg (based on ideal body weight) to a train-of-four (TOF) count of 0. Other outcomes included duration of action (time to TOF ratio ≥ 0.9), intubation conditions using the Fuchs-Buder scale and the Intubating Difficulty Scale (IDS), and occurrence of hoarseness and sore throat postoperatively.

Results

Elderly patients had significantly longer onset time compared with younger patients; 297 seconds (SD 120) vs. 199 seconds (SD 59) (difference: 98 seconds (95% CI: 49–147), P < 0.001)). Duration of action was also significantly longer in elderly patients compared with younger patients; 89 minutes (SD 17) vs. 77 minutes (SD 14) (difference: 12 minutes (95% CI: 2.5–20.5) P = 0.01)). No difference was found in the proportion of excellent intubating conditions (Fuchs-Buder); 19/29 (66%) vs 21/31 (68%) (P = 0.86) or IDS score (P = 0.74). A larger proportion of elderly patients reported hoarseness 24 hours postoperatively; 62% vs 34% P = 0.04.

Conclusion

In elderly patients cisatracurium 0.15 mg/kg had significantly longer onset time and duration of action compared with younger patients. No difference was found in intubating conditions at a TOF count of 0.

Trial registration

Clinicaltrials.gov (NCT04921735, date of registration 10 June 2021).

Rocuronium 0.3 mg/kg or 0.9 mg/kg comparing onset time, duration of action and intubating conditions in patients 80 years and older. A randomized study

BACKGROUND

Limited data exist about the optimal dose of rocuronium for intubation in elderly patients. We hypothesized that rocuronium 0.9 mg kg^-1 would lead to a shorter onset time than 0.3 mg kg^-1 in patients above 80 years.

METHODS

Thirty-four patients were randomized to either rocuronium 0.3 mg kg^-1 or 0.9 mg kg^-1 . The primary outcome was onset time defined as time to train-of-four (TOF) count of 0. Other outcomes included duration of action (time to TOF ratio > 0.9), proportion of excellent intubating conditions using the Fuchs-Buder scale and tracheal intubating conditions using the Intubating Difficulty Scale (IDS).

RESULTS

Rocuronium 0.9 mg kg^-1 resulted in shorter onset time compared to rocuronium 0.3 mg kg^-1 ; 108 sec (SD 40) vs. 228 sec (SD 140) (difference: 119 seconds (95% CI: 41-196), P=0.005)), respectively. However, in 66% of the patients receiving rocuronium 0.3 mg kg^-1 a TOF count of 0 was not obtained. Duration of action was longer after rocuronium 0.9 mg kg^-1 : 118 minutes (SD 43) vs. 46 minutes (SD 13) (difference: 72 minutes (95% CI: 49-95) P<0.0001)), and a greater proportion of excellent intubating conditions (Fuchs-Buder) was obtained; 11/16 (69%) vs 4/18 (22%) (P=0.006). No difference was found regarding IDS score.

CONCLUSION

Rocuronium 0.9 mg kg^-1 resulted in a shorter onset time compared to rocuronium 0.3 mg kg^-1 in patients above 80 years of age. In 66% of the patients receiving rocuronium 0.3 mg kg^-1 a TOF count of 0 was not obtained.

Low-dose hydrocortisone in patients with COVID-19 and severe hypoxia: The COVID STEROID randomised, placebo-controlled trial

Background

In the early phase of the pandemic, some guidelines recommended the use of corticosteroids for critically ill patients with COVID‐19, whereas others recommended against the use despite lack of firm evidence of either benefit or harm. In the COVID STEROID trial, we aimed to assess the effects of low‐dose hydrocortisone on patient‐centred outcomes in adults with COVID‐19 and severe hypoxia.

Methods

In this multicentre, parallel‐group, placebo‐controlled, blinded, centrally randomised, stratified clinical trial, we randomly assigned adults with confirmed COVID‐19 and severe hypoxia (use of mechanical ventilation or supplementary oxygen with a flow of at least 10 L/min) to either hydrocortisone (200 mg/d) vs a matching placebo for 7 days or until hospital discharge. The primary outcome was the number of days alive without life support at day 28 after randomisation.

Results

The trial was terminated early when 30 out of 1000 participants had been enrolled because of external evidence indicating benefit from corticosteroids in severe COVID‐19. At day 28, the median number of days alive without life support in the hydrocortisone vs placebo group were 7 vs 10 (adjusted mean difference: −1.1 days, 95% CI −9.5 to 7.3, P = .79); mortality was 6/16 vs 2/14; and the number of serious adverse reactions 1/16 vs 0/14.

Conclusions

In this trial of adults with COVID‐19 and severe hypoxia, we were unable to provide precise estimates of the benefits and harms of hydrocortisone as compared with placebo as only 3% of the planned sample size were enrolled.

Trial registration: ClinicalTrials.gov: NCT04348305. European Union Drug Regulation Authorities Clinical Trials (EudraCT) Database: 2020‐001395‐15.

Exploring the limits of prolonged apnoea with high-flow nasal oxygen: an observational study

High-flow nasal oxygen is increasingly used for oxygenation during apnoea. Extending apnoea duration using this technique has mainly been investigated during minor laryngeal surgery, but it is unclear how long it can be administered for before it should be discontinued due to acidosis. We aimed to describe the dynamics of arterial blood gases during apnoeic oxygenation with high-flow nasal oxygen with jaw thrust only, to explore the limits of this technique. We included adult orthopaedic patients scheduled for general anaesthesia. After pre-oxygenation, anaesthesia with neuromuscular blockade was induced and high-flow nasal oxygen (70 l.min^-1 ) was continued with jaw thrust as the only means of airway management, with monitoring of vital signs and arterial blood gas sampling every 5 minutes. Apnoeic oxygenation with high-flow nasal oxygen was discontinued when arterial carbon dioxide tension (PaCO₂ ) exceeded 12 kPa or pH fell to 7.15. This technique was used in 35 patients and median (IQR [range]) apnoea time was 25 (20-30 [20-45]) min and was discontinued in all patients when pH fell to 7.15. The mean (SD) PaCO₂ increase was 0.25 (0.06) kPa.min^-1 but it varied substantially (range 0.13-0.35 kPa.min^-1 ). Mean (SD) arterial oxygen tension was 48.6 (11.8) kPa when high-flow nasal oxygen was stopped. Patients with apnoea time > 25 minutes were significantly older (p = 0.025). We conclude that apnoeic oxygenation with high-flow nasal oxygen resulted in a significant respiratory acidosis that varies substantially on the individual level, but oxygenation was maintained.