Smoking does not alter the dose-requirements and the pharmacodynamics of rocuronium

The Effects of Cigarette Smoking on Steroidal Muscular Relaxants and Antibiotics Used: A Prospective Cohort Study

Background: The impact of cigarette smoking on perianesthesia management is not clear elucidated. This paper studies the impact of long-term cigarette smoking on the dose-response of rocuronium and vecuronium used under general anesthesia and the type of antibiotics used after surgery. Methods: We enrolled 240 participants from a teaching hospital in China in which finally enrolled in 221 participants. 106 participants have a history of long-term cigarette use and 115 participants without a history of smoking. All participants received general anesthesia for various surgeries, and rocuronium was used as the muscular relaxant. The primary outcome was the effective onset time of rocuronium after adjusting for its dose. The secondary outcomes included a recovery index and the time of muscle recovery changing from 25 to 75%. Results: There was no measurable difference in the muscle relaxant onset time, duration of effectiveness, 75% recovery, recovery index, dose of opiates, anesthetics during surgery, or complication rate between smokers or non-smokers. However, the results showed a significant difference in antibiotic use between smokers and non-smokers (chi-squared = 13.695, p < 0.001), and a significant difference in the type of antibiotics used (chi-squared = 21.465, p = 0.003). Smokers had a significantly higher rate of cefathiamidine use. Conclusion: Smoking cigarettes had no effect on muscle relaxants used under general anesthesia, but patients who had a history of smoking were more likely to receive antibiotics after surgery. Clinical Trial Registration: http://www.chictr.org.cn/index.aspx, identifier ChiCTR-OIC-16009157.

Effect of Smoking on Reversing Neuromuscular Block

OBJECTIVE

Rocuronium is a non-depolarising, intermediate-acting, monoquaternary amino steroid and was brought into clinical use as a potentially ideal muscle relaxant. Post-operative residual curarisation (PORC) results from the prolonged effects of non-depolarising neuromuscular blocking agents. This is a common problem and seriously affects patient safety. No recent study has investigated the effects of sugammadex on smokers, which is often used to restore neuromuscular block and avoid PORC. This study compares the severity of the effects of sugammadex used for antagonising rocuronium bromide and antagonism durations in smokers and non-smokers.

METHODS

This randomised, prospective study included 40 patients scheduled for elective surgery and belonging to classes I and II based the American Society of Anesthesiologists classification, who were either smokers for at least 10 years or non-smokers. Patients underwent routine and neuromuscular monitoring. At induction, 2 mg kg^-1 propofol and 1 mcg kg^-1 intravenous fentanyl were applied. After the loss of eyelash reflex, 0.6 mg kg^-1 intravenous rocuronium was administered. Patients were intubated at train of four (TOF) 2. Anaesthesia was continued with 50% O₂+50% air and 2% sevoflurane. Rocuronium, 0.15 mg kg^-1, was administered at TOF 2 during the operation. At the end of the operation, 2 mg kg^-1 sugammadex was administered. The times until TOF 0.7, 0.8 and 0.9 were recorded.

RESULTS

Intubation time was 132.8±46.4 s for smokers and 127.6±32.7 s for non-smokers. After sugammadex administration, the time to TOF 0.7 was 153.3±54.7 s in smokers and 125±67.2 s in non-smokers. The times were 178.4±58.8 and 146.6±72.6 s for TOF 0.8 and 200.8±55.8 s and 170.4±77.8 s for TOF 0.9 in smokers and non-smokers, respectively.

CONCLUSION

Although not statistically significant, the time to reach each TOF was longer for smokers. Larger populations and different perspectives are needed to find if sugammadex use is affected by smoking, which has negative effects on the body.

Das präoperative „Rauchverbot“

For decades it has been assumed, that smoking within 6 hours of anesthesia and surgery raises the incidence of perioperative cardiopulmonary complications (PPC) including aspiration. Therefore, every patient is advised to stop smoking at the day before surgery, and not to smoke at all at the day of surgery. If the patient does not follow this advice, this will result in a postponement of anesthesia and surgery. The present article aims at re-investigating the scientific basis of this dogma in anesthesia, which virtually forbids smoking at short-term prior to surgery. The influence of short-term (6 h) abstinence from smoking on the perioperative pulmonary morbidity has not been systematically investigated. Interestingly, giving up smoking less than two months prior to surgery does not significantly decrease, but rather may increase the incidence of PPC. With respect to the risk of aspiration, smoking does not increase either the volume or the acidity of gastric juices. A short-lived reduction in the tone of the lower esophageal sphincter is reversible within minutes after termination of smoking. While the emptying of liquid gastric juices is not influenced by smoking, there is a certain delay in the propulgation of solid food. This effect, however, is probably of no clinical relevance in patients, who had their last solid meal the evening before surgery. Hence, we conclude that the anesthesia dogma, which rules out smoking shortly prior to anesthesia, cannot be based on an otherwise increased incidence of pulmonary aspiration or other pulmonary morbidity. However, acute smoking (probably by an increase in COHb) may increase the incidence of myocardial ischemia during exercise and anesthesia. With reference to this possible cardiac complication it still seems reasonable to discourage smoking at least 12 to 48 hours prior to surgery in patients with elevated cardiac risk.

The effect of environmental tobacco smoke on the dose requirements of rocuronium in children

BACKGROUND

Smoking affects the pharmacodynamic and pharmacokinetic behaviour of several drugs. The aim of this study was to evaluate the effects of environmental tobacco smoke on onset and recovery time after single dose rocuronium in children.

METHODS

Forty children between 4 and 10 years were enrolled into the study. Children who have no familial smoking history were included in the first group whereas passive smokers included in the second group. Sevoflurane in 50% O2 and 50% N2O was used for induction of anaesthesia. Evoked adductor pollicis electromyography was used to monitor neuromuscular block. The T95 and T25 values were recorded.

RESULTS

The T95 values (+/-sd) for rocuronium were 110.1 +/- 39.3 s and 79.3 +/- 35.6 s for group 1 and group 2, respectively (P < 0.05). The T25 value of group 2 was 40.1 +/- 10.6 min and compared with group 1 values (30.85 +/- 7.02 min) it was significantly longer (P < 0.01).

CONCLUSION

This study shows that passive smoking children consume less rocuronium than nonsmokers during similar anaesthesia. We think that a history of passive smoking must also be taken into consideration during preoperative evaluation of paediatric patients.