Confounding factors to predict the awakening effect-site concentration of propofol in target-controlled infusion based on propofol and fentanyl anesthesia

Comparison of recovery profiles in target-controlled infusions (TCI) versus manually controlled infusions for total intravenous anesthesia (TIVA) in laparoscopic surgeries. A randomized controlled trial

Background and Aims

Considerable importance has been attached to early recovery and discharge readiness after surgeries. Many centers use total intravenous anesthesia (TIVA) as their anesthesia technique of choice. Target-controlled infusions (TCI) have been proposed as a method to precisely deliver continuous infusions of propofol and opioids as compared to the traditionally used manual-controlled infusion (MCI) methods. However, TCI has also been shown to result in the administration of larger doses of propofol which could cause delayed emergence and recovery from anesthesia. Studies involving TCI have focused mainly on its effects on anesthesia induction but not much literature is available on recovery profiles of patients on TCI. This study was designed to compare the effect of conventionally used MCI methods versus the target-controlled infusion (TCI) method of administering TIVA on recovery characteristics in patients undergoing laparoscopic surgery.

Material and Methods

This was a prospective randomized interventional study on 54 patients. Our primary objective was to compare the rates of recovery from anesthesia as judged by four parameters. Time to return of spontaneous ventilation, time to respond to verbal commands, time to extubation, and time to shift patient out of the operating room after stoppage of propofol infusion. As secondary objectives, intraoperative average bispectral index (BIS) values and total anesthetic drugs (propofol and fentanyl) consumption were also compared.

Results

We noted that for laparoscopic surgeries lasting less than 4 hours, both MCI and TCI techniques of TIVA have comparable rates of recovery after the stoppage of propofol infusion. Total consumption of propofol and fentanyl was also similar; however, with the use of the TCI method of TIVA, better depth of anesthesia as evidenced by lower average BIS levels was noted.

Conclusion

Recovery rates after TIVA using a target-controlled infusion (TCI) system are similar to BIS-guided MCIs in patients undergoing laparoscopic surgery lasting less than 4 hours. TCI resulted in better depths of anesthesia though per kg/min consumption of propofol was found to be more.

Factors Associated with Prolonged Extubation after Total Intravenous Anesthesia in Patients Undergoing Vestibular Schwannoma Resection

OBJECTIVE

To identify factors associated with prolonged tracheal extubation after vestibular schwannoma resection in patients receiving propofol-remifentanil-based total intravenous anesthesia (TIVA).

STUDY DESIGN

Single-center retrospective study of vestibular schwannoma resection performed by a single neurosurgeon between July 2018 and September 2021.

SETTING

Tertiary academic medical center.

PATIENTS

Adults receiving TIVA for vestibular schwannoma resection, classified according to extubation time: non-prolonged extubation (<15 min) and prolonged extubation (≥15 min).

MAIN OUTCOME MEASURES

Time from end of surgery to extubation, demographic parameters, intraoperative variables, and familiarity between the anesthesia provider and the neurosurgeon were analyzed. Predictors for prolonged extubation were analyzed via multivariate analysis. The primary outcome was the incidence of prolonged extubation. The secondary outcome was factors associated with prolonged tracheal extubation.

RESULTS

A total of 234 cases were analyzed. The median (interquartile range) extubation time was 9.4 minutes (7.2, 12.2 min). Extubation was prolonged in 39 patients (16.7%). Factors predicting prolonged extubation were significant blood loss (odds ratio [OR], 12.8; 95% confidence interval [CI], 2.6-61.7; p = 0.002), intraoperative neuromuscular blocking drug infusion (OR, 6.6; 95% CI, 2.8-15.7; p < 0.001), and lack of familiarity between the anesthesia provider and neurosurgeon (OR, 4.4; 95% CI, 1.5-12.3; p = 0.005).

CONCLUSION

Significant blood loss, intraoperative neuromuscular blocking drug infusion, and lack of familiarity between anesthesia provider and neurosurgeon were associated with prolonged extubation following TIVA for vestibular schwannoma resection.

Impact of short-acting vs. standard anaesthetic agents on obstructive sleep apnoea: a randomised, controlled, triple-blind trial

Sleep apnoea is associated with negative outcomes following general anaesthesia. Current recommendations suggest using short‐acting anaesthetic agents in preference to standard agents to reduce this risk, but there is currently no evidence to support this. This randomised controlled triple‐blind trial tested the hypothesis that a combination of short‐acting agents (desflurane‐remifentanil) would reduce the postoperative impact of general anaesthesia on sleep apnoea severity compared with standard agents (sevoflurane‐fentanyl). Sixty patients undergoing hip arthroplasty under general anaesthesia were randomised to anaesthesia with desflurane‐remifentanil or sevoflurane‐fentanyl. Respiratory polygraphy was performed before surgery and on the first and third postoperative nights. The primary outcome was the supine apnoea‐hypopnoea index on the first postoperative night. Secondary outcomes were the supine apnoea‐hypopnoea index on the third postoperative night, and the oxygen desaturation index on the first and third postoperative nights. Additional outcomes included intravenous morphine equivalent consumption and pain scores on postoperative days 1, 2 and 3. Pre‐operative sleep study data were similar between groups. Mean (95%CI) values for the supine apnoea‐hypopnoea index on the first postoperative night were 18.9 (12.7–25.0) and 21.4 (14.2–28.7) events.h⁻¹, respectively, in the short‐acting and standard anaesthesia groups (p = 0.64). Corresponding values on the third postoperative night were 28.1 (15.8–40.3) and 38.0 (18.3–57.6) events.h⁻¹ (p = 0.34). Secondary sleep‐ and pain‐related outcomes were generally similar in the two groups. In conclusion, short‐acting anaesthetic agents did not reduce the impact of general anaesthesia on sleep apnoea severity compared with standard agents. These data should prompt an update of current recommendations.

Early postoperative recovery in operating room after desflurane anesthesia combined with Bispectral index (BIS) monitoring and warming in lengthy abdominal surgery: a randomized controlled study

BACKGROUND

This study aimed to determine whether the use of desflurane (DES) anesthesia combined with bispectral index (BIS) monitoring and warming is effective in reducing anesthesia-controlled operating room time (ACT) in patients undergoing lengthy abdominal surgery.

METHODS

Seventy patients, 40 years of age or older, undergoing abdominal surgery expected to last three to five hours were randomly assigned to the DES group (n = 35) or the control group (n = 35). Patients in the DES group were maintained with desflurane anesthesia and received BIS monitoring and warming. Patients in the control group were given non-desflurane anesthesia for maintenance, and the usage of BIS monitoring and warming were not mandatory and determined by anesthesia care providers. Early postoperative recovery times were recorded.

RESULTS

The times to extubation (8.8 ± 8.5 vs 14.7 ± 13.7 min, P = 0.035), eye opening (8.4 ± 8.6 vs 14.4 ± 13.4 min, P = 0.028), responds on command (8.2 ± 8.5 vs 14.4 ± 13.0 min, P = 0.022), and the ACT (23.8 ± 11.4 vs 32.7 ± 15.4 min, P = 0.009) were significantly less in the DES group than that in the control group. The postanesthesia care unit (PACU) length of stay, incidence of prolonged extubation, and surgeon and anesthesiologist satisfaction were similar in two groups. Also, the result of multivariable linear regressions showed that patients who were younger, female, lower BMI and non-DES anesthesia regimen resulted in prolonged extubation.

CONCLUSIONS

Desflurane anesthesia combined with BIS monitoring and warming is associated with early postoperative recovery in lengthy abdominal surgery.

TRIAL REGISTRATION

ChiCTR-INR-17013333 . Date of registration: November 11, 2017.

Effect site concentration of propofol at induction and recovery of anaesthesia - A correlative dose-response study

BACKGROUND AND AIMS

Sound knowledge about effect site concentration (Ce) of propofol aids in smooth induction, maintenance and early recovery. We studied the correlation between Ce of propofol at loss of response to verbal command and recovery concentration using target-controlled infusion (TCI) in Indian patients who underwent spine surgeries.

METHODS

Ninety patients undergoing spine surgeries were included. Total intravenous anaesthesia (TIVA) technique with TCI for propofol using modified Marsh model was used. Entropy and neuromuscular transmission were used. Ce at induction and recovery and the corresponding state entropy (SE) values were noted.

RESULTS

The mean propofol Ce and SE at induction were 2.34 ± 0.24 μg/ml and 52 ± 8, respectively. The mean propofol Ce and SE at recovery were 1.02 ± 0.22 μg/ml and 86.80 ± 2.86, respectively. The Ce at recovery was approximately 50% of the induction value. The correlation coefficient 'r' between Ce at induction and recovery was 0.56. The mean infusion dose of propofol during the maintenance period was 81 ± 14.33 μg/kg/min. The average induction dose of propofol was 1.17 ± 0.2 mg/kg.

CONCLUSION

There is a positive correlation between Ce at induction and recovery. Ce for recovery may have to be set at a lower level during TCI-TIVA and appropriately infusion should be stopped for early recovery. The induction and maintenance doses of propofol are lower than the recommended doses. Data emphasise the need for pharmacokinetic model based on our population characteristics.

Analysis of anesthesia-controlled operating room time after propofol-based total intravenous anesthesia compared with desflurane anesthesia in functional endoscopic sinus surgery

Anesthesia technique may contribute to the improvement of operation room (OR) efficiency by reducing anesthesia-controlled time. We compared the difference between propofol-based total intravenous anesthesia (TIVA) and desflurane anesthesia (DES) for functional endoscopic sinus surgery (FESS) undergoing general anesthesiaWe performed a retrospective study using data collected in our hospital to compare the anesthesia-controlled time of FESS using either TIVA via target-controlled infusion with propofol/fentanyl or DES/fentanyl-based anesthesia between January 2010 and December 2011. The various time intervals (surgical time, anesthesia time, extubation time, total OR stay time, post anesthesia care unit [PACU] stay time) and the percentage of prolonged extubation were compared between the 2 anesthetic techniques.We included data from 717 patients, with 305 patients receiving TIVA and 412 patients receiving DES. An emergence time >15 minutes is defined as prolonged extubation. The extubation time was faster (8.8 [3.5] vs. 9.6 [4.0] minutes; P = .03), and the percentage of prolonged extubation was lower (7.5% vs. 13.6%, risk difference 6.1%, P < .001) in the TIVA group than in the DES group. However, there was no significant difference between ACT, total OR stay time, and PACU stay time.In our hospital, propofol-based TIVA by target-controlled infusion provide faster emergence and lower chance of prolonged extubation compared with DES anesthesia in FESS. However, the reduction in extubation time may not improve OR efficiency.

Efficacy of sevoflurane as an adjuvant to propofol-based total intravenous anesthesia for attenuating secretions in ocular surgery

BACKGROUND

The incidence of nasal secretions into the operative field is as high as 5% in ophthalmic surgery under general anesthesia. It may induce postoperative endophthalmitis. Secretions under propofol-based total intravanous anesthesia (TIVA) are greater than sevoflurane anesthesia during surgery. Postoperative nausea and vomiting (PONV) after inhalational anesthesia is higher than TIVA and may increase intraocluar pressure. We investigated the effect of sevoflurane combination with propofol-based TIVA on nasopharyngeal secretions and PONV in ocular surgery.

METHODS

Fifty patients undergoing ocular operations were randomly assigned for propofol-based TIVA or propofol/sevoflurane anesthesia. In the TIVA group (n = 25), anesthesia was induced and maintained with propofol and fentanyl; in the propofol/sevoflurane group (n = 25), 1% sevoflurane anesthesia was added.

RESULTS

Nasopharyngeal excretion volume was significantly higher in the propofol-based TIVA group than in the propofol/sevoflurane group (31.0 ± 18.1 vs 13.7 ± 12.6 ml; P < .001). No significant difference in extubation time was noted (propofol-based TIVA: 6.4 ± 3.6 vs propofol/sevoflurane: 7.4 ± 3.0 minutes; P = .34). No postoperative endophthalmitis or PONV in both groups was observed.

CONCLUSION

Sevoflurane attenuated secretions under propofol-based TIVA and did not increase the incidence of PONV or prolonged extubation in ocular surgery.

Relationship between anesthesia and postoperative endophthalmitis: A retrospective study

Previous study showed that patients under general anesthesia (GA) had nasopharyngeal secretions on the face at the end of ocular surgery, especially in propofol-based total intravenous anesthesia (TIVA), it might induce postoperative endophthalmitis. Therefore, we conducted a retrospective study to compare the incidence of endophthalmitis after ocular surgery under topical, inhalation anesthesia, and propofol-based TIVA in our medical center from 2011 to 2015.A total of 21,032 patients were included, and we evaluated epidemiologic factors, systemic diseases, other ocular pathologic characteristics, complications during the surgery, technique of ocular surgery, method of antibiotic prophylaxis, vitreous culture, and vision outcome in these patients.Fifteen endophthalmitis cases among 21,032 operations reported, equaling an incidence of 0.071%. The incidence rates under topical, inhalation anesthesia, and propofol-based TIVA were 0.083%, 0.039%, and 0%, respectively (P = 0.39). Moreover, the risk of endophthalmitis under GA (0.024%) was significantly lower than topical anesthesia (0.083%) (P < 0.001). We also found that elder was the risk factor for endophthalmitis following ocular surgery.In conclusion, propofol-based TIVA or inhalation anesthesia did not increase the risk of endophthalmitis after ocular surgery. Thus, GA was not a risk factor for postoperative endophthalmitis. By contrast, elder was the risk factor for postoperative endophthalmitis.

Planning for operating room efficiency and faster anesthesia wake-up time in open major upper abdominal surgery

Reducing anesthesia-controlled time (ACT) may improve operation room (OR) efficiency result from different anesthetic techniques. However, the information about the difference in ACT between desflurane (DES) anesthesia and propofol-based total intravenous anesthesia (TIVA) techniques for open major upper abdominal surgery under general anesthesia (GA) is not available in the literature.This retrospective study uses our hospital database to analyze the ACT of open major upper abdominal surgery without liver resection after either desflurane/fentanyl-based anesthesia or TIVA via target-controlled infusion with fentanyl/propofol from January 2010 to December 2011. The various time intervals including waiting for anesthesia time, anesthesia time, surgical time, extubation time, exit from OR after extubation, total OR time, and postanesthetic care unit (PACU) stay time and percentage of prolonged extubation (≥15 minutes) were compared between these 2 anesthetic techniques.We included data from 343 patients, with 159 patients receiving TIVA and 184 patients receiving DES. The only significant difference is extubation time, TIVA was faster than the DES group (8.5 ± 3.8 vs 9.4 ± 3.7 minutes; P = 0.04). The factors contributed to prolonged extubation were age, gender, body mass index, DES anesthesia, and anesthesia time.In our hospital, propofol-based TIVA by target-controlled infusion provides faster emergence compared with DES anesthesia; however, it did not improve OR efficiency in open major abdominal surgery. Older, male gender, higher body mass index, DES anesthesia, and lengthy anesthesia time were factors that contribute to extubation time.

Comparison of Anesthesia-Controlled Operating Room Time between Propofol-Based Total Intravenous Anesthesia and Desflurane Anesthesia in Open Colorectal Surgery: A Retrospective Study

We conducted a retrospective study to investigate the anesthesia-controlled time and factors that contribute to prolonged extubation in open colorectal surgery. Using our hospital database, demographic data, various time intervals (waiting for anesthesia time, anesthesia time, surgical time, emergence time, exit from operating room after extubation, total operating room time, and post-anesthesia care unit stay time), and incidence of prolonged extubation (≥ 15 mins), were compared between patients who received desflurane/fentanyl-based anesthesia and total intravenous anesthesia via target-controlled infusion with fentanyl/propofol. Logistic regression analyses were performed to assess the association between variables that contributed to prolonged extubation. In conclusion, the anesthesia-controlled time was similar in desflurane anesthesia and propofol-based total intravenous anesthesia for open colorectal surgery in our hospital. Surgical time greater than 210 minutes, as well as age, contributed to prolonged extubation.