Asleep-awake-asleep technique in children during strabismus surgery under sufentanil balanced anesthesia

A simple marking system for accurate intraoperative monitoring and adjustment of cyclotorsion strabismus surgery

Ocular cyclotorsion is treatable only with surgery. The surgical procedure must be tailored individually to the specific etiologies causing the horizontal and vertical strabismus and its torsional components. An adjustable surgical approach is often used for postoperative or intraoperative adjustments. However, the methods currently used have some limitations. In this study, we propose a simple intraoperative marking system for all cyclotorsion correction surgery. The proposed marking system used three sets of surface markers: external horizontal markings, ocular horizontal markings, and surgical torsion markings, drawn in sequence. We retrospectively analyzed the surgical results using this novel marking system in this single-center, single-surgeon study. Fifteen patients with cyclotorsion who underwent treatment using the proposed marking system as an intraoperative aid between August 2019 and August 2021 were included. The medical charts were thoroughly reviewed, and the pre-and postoperative subjective and objective cyclotorsion were analyzed. Among the study subjects (10 males, 5 females; age range: 6-89 years), 13 had excyclotorsion and 2 incyclotorsion. Preoperative mean net subjective cyclotorsion measured by the double Maddox rod (DMR) test was 6.0° (standard deviation: 10.8°) and mean net disc-to-fovea angle (DFA) was 20.23° (13.21°). The postoperative net DMR and DFA were 0.2° (2.1°) and 14.09° (5.97°), respectively. The mean absolute net DMR and DFA being treated were 9.8° (4.8°) and 9.76° (4.61°). Overall, the proposed intraoperative marking system is a simple and quantitative method to assess, monitor, and adjust the torsional aspect for all strabismus surgeries.

Comparison of the Sedative and Analgesic Effects of Dexmedetomidine-Remifentanil and Dexmedetomidine-Sufentanil for Liposuction: A Prospective Single-Blind Randomized Controlled Study

BACKGROUND

Dexmedetomidine had sedative and analgesic effects and did not produce significant respiratory depression at therapeutic doses.

AIMS

To compare the sedative and analgesic effects and safety of dexmedetomidine combined with remifentanil or sufentanil in patients undergoing liposuction.

METHODS

A total of 100 subjects were randomized 1:1 to two groups: Group R and Group S. First, patients were administered midazolam 0.02 mg·kg^-1. Anesthesia was induced with an intravenous infusion of dexmedetomidine 1 µg kg^-1 (15 min) and remifentanil 0.1 µg kg^-1 min^-1 (Group R) or sufentanil 0.1 µg kg^-1h^-1 (Group S). Anesthesia was maintained with an intravenous infusion of dexmedetomidine 1.0 µg kg^-1h^-1, midazolam 0.015 mg kg^-1h^-1, remifentanil 0.1 µg kg^-1min^-1 (Group R), or sufentanil 0.1 µg kg^-1h^-1 (Group S). Hemodynamic and respiratory changes, modified OAA/S score and BIS values, postoperative Visual Analogue Scale pain scores, satisfaction of the patient and surgical team with the procedure, and adverse events and recovery time were recorded.

RESULTS

Group R received significantly less midazolam and midazolam per hour compared to Group S (Group R vs. Group S: 3.4 ± 1.7 mg vs. 5.1 ± 2.0 mg, P < 0.0001; 1.5 ± 0.7 mg/h vs. 1.9 ± 0.6 mg/h, P = 0.002). The incidence of physical or verbal expressions of pain at the start of surgery was significantly lower in Group R compared to Group S (2 [4.3%] vs. 12 [26.7%], P = 0.003). Patient satisfaction with the procedure was significantly higher in Group R compared to Group S (3.9 ± 0.3 vs. 3.1 ± 0.3, P < 0.0001).

CONCLUSION

Dexmedetomidine-remifentanil and dexmedetomidine-sufentanil were effective and safe sedative and analgesic agents for liposuction. Hemodynamic stability was maintained. Dexmedetomidine-remifentanil might be associated with improved analgesic effects compared to dexmedetomidine-sufentanil.

LEVEL OF EVIDENCE II

Evidence was obtained from at least one properly designed randomized controlled trial. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Estimation of the plasma effect site equilibration rate constant of sufentanil in children using the time to peak effect of heart rate and blood pressure

Objectives:

Although targeting the effect site concentration may offer advantages over the traditional forms of administering intravenous anesthetics, it is not applicable for sufentanil in children because its plasma effect site equilibration rate constant (k_e0) is not known yet. We estimated k_e0 of sufentanil in children using the time to peak effect (t_peak) method.

Materials and Methods:

Under general anesthesia, sufentanil t_peak was measured after administration of a submaximal bolus dose by means of the decrease in heart rate, blood pressure and calculated approximate entropy (ApEn) of electroencephalogram in 105 children (age range: 3–11 years). k_e0 was estimated using t_peak and known sufentanil pharmacokinetic parameters in normal children.

Results:

The mean t_peaks were measured as 44 ± 22 s and 227 ± 91 s by heart rate and by mean blood pressure respectively. The estimated k_e0 were 5.16/min and 0.49/min by heart rate and blood pressure respectively. t_peak could not be measured using the ApEn, thus k_e0 could not be calculated by ApEn in children.

Conclusions:

Shorter measured sufentanil t_peak by heart rate compared to blood pressure indicate that the heart rate decrease faster than decreasing of blood pressure. Moreover, the calculated sufentanil k_e0 in children depends on the pharmacodynamics parameters.

Asleep-awake-asleep regimen for epilepsy surgery: a prospective study of target-controlled infusion versus manually controlled infusion technique

BACKGROUND

Asleep-awake-asleep (AAA) protocol for epilepsy surgery is a unique opportunity to accurately map epilepsy foci involved in motor and eloquent areas, allowing the operator to optimize the resection. Two different application modes of intravenous anesthesia for AAA craniotomies are widely used: infusion by means of target-controlled infusion (TCI) and traditional manually-controlled infusion (MCI). We conducted this study to examine whether intravenous anesthesia using the TCI system with propofol and remifentanil would be a more effective method than MCI in AAA epilepsy surgery.

METHODS

This prospective and single center study compared patients undergoing either TCI or MCI techniques for functional AAA epilepsy surgery. 35 cases used TCI including TCI-E (resection of epileptogenic foci in an eloquent area, n = 18) and TCI-M (resection of epileptogenic foci in a motor area, n = 17). Thirty-six cases used MCI including MCI-E (epileptogenic foci in an eloquent area, n = 16) and MCI-M (epileptogenic foci in a motor area, n = 20). Bispectral index value and hemodynamic profiles at different time points during the awake phase were recorded along with time for awakening and the occurrences of adverse events.

RESULTS

The TCI technique significantly shortened intraoperative awakening times during the third phase, TCI-E vs MCI-E 12.82 min ± 6.93 vs 29.9 min ± 9.04 (P = .000) and TCI-M vs MCI-M 16.8 min ± 5.19 vs 30.91 min ± 15.32 (P = .010). During the awake phase, the highest bispectral index score values appeared in the TCI-E group at all-time points. Mean arterial pressure and heart rate were more stable in the TCI-E group compared with the MCI-E group during the awake phase. Tachycardia and hypertension were most common in the MCI-E group (52.9% and 29.4%, P = .001 and P = .064).

CONCLUSION

We found the superiority of TCI, which is faster intraoperative awakening and better hemodynamics along with secure airway management conditions. It is suggested that the TCI technique may be a feasible and effective technique and it might be a viable replacement of the MCI technique for AAA epilepsy surgery.

Median effective effect-site concentration of sufentanil for wake-up test in adolescents undergoing surgery: a randomized trial

BACKGROUND

To determine the median effective concentration of sufentanil as an analgesic during wake-up tests after sevoflurane anesthesia during surgery for adolescent idiopathic scoliosis (AIS).

METHODS

This is a randomised controlled trial. Sixty patients aged 13-18 years scheduled for AIS surgery were randomized into six groups of 10 patients each to receive target effect-site concentrations of sufentanil of 0.19, 0.1809, 0.1723, 0.1641, 0.1563, and 0.1489 ng/ml (target concentration ratio, 1.05). Wake-up time was recorded. Median EC50 and 95% confidence interval (CI) for sufentanil target-controlled infusion (TCI) were determined using Kärber's method. The primary outcome was median EC50 for sufentanil TCI as an analgesic during the wake-up test after sevoflurane anesthesia during surgery for AIS.

RESULTS

The EC50 and 95% CI of sufentanil TCI were 0.1682 ng/ml and 0.1641 ~ 0.1724 ng/ml, respectively.

CONCLUSIONS

The EC50 of sufentanil TCI was 0.1682 ng/ml (95% CI: 0.1641 ~ 0.1724 ng/ml) during sevoflurane anesthesia in adolescents undergoing surgery for idiopathic scoliosis with intraoperative wake-up tests.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: ChiCTR-TTRCC-12002696.