A comparison of intravenous sugammadex and neostigmine + atropine reversal on time to consciousness during wake-up tests in spinal surgery

Objective

The effect of sugammadex on consciousness is not yet fully understood. This prospective, randomized, double-blind, multicenter study was performed to compare the effects of intravenous (IV) sugammadex and neostigmine + atropine reversals on time-to-consciousness during intraoperative wake-up tests in patients undergoing spinal surgery.

Subjects and Methods

A total of 66 American Society of Anesthesiologists I-II patients aged 10-25 years undergoing spinal surgery were recruited. In all patients, bispectral index (BIS), motor-evoked potential (MEP), somatosensory-evoked potentials (SSEP), and train-of-four (TOF) scores were monitored. Patients received the same total IV anesthesia protocol with a propofol-remifentanil mixture. Patients were randomly allocated into two groups. During wake-up test, when the TOF count reached 2 (T₂), either sugammadex 2 mg.kg^-1 in group S or neostigmine 0.04 mg.kg^-1 + atropine 0.01 mg.kg^-1 in group N were administered. BIS₉₀, SSEP₉₀, MEP₉₀ was recorded when TOF ratio reached 90, whereas time-to-consciousness (Time_cons) was recorded when the patient responded to verbal commands.

Results

BIS₉₀ (77.4 ± 4.7, 74.8 ± 3.7), SSEP₉₀(36 ± 9.9, 29.7 ± 8.5), and MEP₉₀ (465.3 ± 34.8, 431.3 ± 28.2) values were significantly greater in group S than in group N (P < 0.05 for each variables). Time_cons was significantly shorter with sugammadex than with the neostigmine + atropine combination (P < 0.05).

Conclusion

Using IV sugammadex 2 mg.kg^-1 reversal provides faster responses to verbal commands than neostigmine-atropine combination during the intraoperative wake-up test in patients undergoing spinal surgery because the time to consciousness was significantly shorter. This difference was thought to be related with faster return of neuromuscular transmission because the TOF ratio was >0.9 well before return of consciousness in both groups.

A randomized controlled study evaluating the effects of the temperature of insufflated CO2 on core body temperature and blood gases (an experimental study)

BACKGROUND

Heated carbon dioxide (CO2) was used for pneumoperitoneum (Pp) to prevent hypothermia. This study aimed to investigate the relationship between the temperature of the insufflated CO2 and blood gases together with the core body temperature (CBT).

METHODS

A prospective controlled study was performed with 24 pigs weighing approximately 20 kg randomized into four groups of 6 pigs each. A pneumoperitoneum at 12 mmHg of pressure was applied for 60 min with the pig under general anesthesia. The CO2)temperature was 22 degrees C in group 1, 37 degrees C in group 2, and 7 degrees C in group 3. In the "sham" group, pneumoperitoneum was not applied. Arterial blood pH and partial pressure of CO2 (PaCO2) were analyzed before insufflation, every 15 min during the pneumoperitoneum, and 15 min after the desufflation. The CBT was recorded before the insufflation, every 20 min during pneumoperitoneum, and 20 min after the desufflation. Blood gas analyses and CBT records for the "sham" group were performed at the same intervals.

RESULTS

Arterial blood pH gradually decreased during pneumoperitoneum. At the 60th minute of pneumoperitoneum, a minimum decrease in arterial blood pH (0.04; p = 0.027) and a minimum increase in PaCO2 (3.67; p = 0.027) were recorded in group 3, whereas a maximum decrease in arterial blood pH (0.18; p = 0.027) and a maximum increase in PaCO2 (17.17; p = 0.027) were recorded in group 2. There was a significant negative correlation between PaCO2 and arterial blood pH in all the groups (r = -0.993; p < 0.01). The mean values of CBT decreases were statistically significant in all the groups: group 1 (p = 0.023), group 2 (p = 0.026), group 3 (p = 0.026), and "sham" group (p = 0.024).

CONCLUSIONS

The changes in PaCO2 were directly proportional and the changes in pH contrarily proportional to the temperature of the insufflated CO2. Significant differences in CBT decreases were found between the groups receiving heated gas and room temperature gas and the groups receiving heated gas and gas below room temperature.