The efficacy and safety of ciprofol use for the induction of general anesthesia in patients undergoing gynecological surgery: a prospective randomized controlled study.

BACKGROUND: Ciprofol is a recently developed, short-acting γ-aminobutyric acid receptor agonist sedative that is more potent than propofol, but there have been few clinical studies of this agent to date. Here, we sought to examine the safety and efficacy of ciprofol use for the induction of general anesthesia in individuals undergoing gynecological surgery. METHODS: Women between the ages of 18 and 60 years (ASA physical status 1 or 2) who were scheduled to undergo elective gynecological surgery under general anesthesia were randomly assigned to two equally sized groups in which anesthesia induction was performed using either ciprofol or propofol. General anesthesia induction success rates were the primary outcome for this study, while secondary outcomes included changes in BIS during the 10 min following the first administration of the study drug, the duration of successful induction, and adverse event incidence. RESULTS: A total of 120 women were included in the study. A 100% rate of successful induction was achieved in both the ciprofol and propofol groups, with no significant differences between these groups with respect to the duration of successful induction (34.8 ± 15.5 s vs 35.4 ± 9.5 s, P = 0.832), the time to the disappearance of the eyelash reflex (33.7 ± 10.6 s vs 34.0 ± 6.5 s, P = 0.860), or tracheal intubation (58.2 ± 31.1 s vs 53.9 ± 25.4 s, P = 0.448). Adverse event rates, including intubation responses, were significantly lower in the ciprofol group as compared to the propofol group(20% vs 48.33%, P = 0.0019). Ciprofol was associated with reduced injection pain relative to propofol (16.7% vs 58.3%, P < 0.001). CONCLUSIONS: Ciprofol exhibits comparable efficacy to that of propofol when used for the induction of general anesthesia in individuals undergoing gynecological surgery and is associated with fewer adverse events.

Repeated Sevoflurane Exposure in Neonatal Rats Enhances the Sensitivity to Pain and Traumatic Stress Later in Juvenile Life.

Purposeː: Sevoflurane exposure in the neonatal period of rodent animals was reported to be associated with neuroendocrine dysregulations later in life. We tested the hypothesis that repeated sevoflurane exposure in neonatal rats enhances the sensitivity to pain and acute traumatic stress response later in juvenile life and investigated whether the neonatal brain depolarizing γ-aminobutyric acid type A receptor (GABAAR) activity is involved in mediating these abnormalities. Methodsː: The postnatal 6 days (P6) Sprague-Dawley male rat pups pretreated with vehicle or the NKCC1 inhibitor, bumetanide, received sequential exposures to 2.1% sevoflurane exposure for 2 hours daily in 3 consecutive days. Resultsː: The results showed that repeated exposures to sevoflurane in neonatal rats significantly reduced the paw withdrawal thermal latency (PWTL) at P9, P45. Repeated exposures to sevoflurane in neonatal rats did not significantly affect the basal secretion of serum corticosterone at juvenile period P45, whereas the level of corticosterone for neonatal sevoflurane-exposed rats at P45 was significantly higher than the CON group after subject to conditioned fear traumatic stress (CFTS). The resulting NKCC1/KCC2 mRNA ratio was significantly increased immediately after the neonatal rats received the last sevoflurane exposure, which was alleviated by pretreated with the NKCC1 inhibitor bumetanide. Conclusionː: Repeated exposures to sevoflurane in neonatal rats enhanced the sensitivity to pain and acute traumatic stress response in juvenile life. The neonatal brain depolarizing GABAAR activity is involved in mediating these abnormalities.

Repeated Sevoflurane Exposures in Neonatal Rats Increased the Brain Vulnerability to Future Stress Exposure and Resulted in Fear Extinction Deficit.

Sevoflurane anesthesia during neonatal period was reported to sensitize the rodent animals to stress later in life. The authors tested the hypothesis that repeated sevoflurane exposures in neonatal rats increased the brain vulnerability to future stress exposure and resulted in fear extinction deficit and investigated whether the neonatal brain depolarizing γ-aminobutyric acid type A receptor (GABAAR) is involved in mediating these abnormalities. Neonatal Sprague-Dawley male rats, pretreated with vehicle or the NKCC1 inhibitor, bumetanide, received sequential exposures to 3% sevoflurane for 2 h on postnatal days (P) 5, P6, and P7 and then were exposed to electric foot shock stress in fear conditioning training at P14. Juvenile rats at different developmental brain stage receiving identical sevoflurane exposures on P25, P26, and P27 were also studied. The results showed repeated sevoflurane exposures in neonatal rats and increased the cation-chloride cotransporters NKCC1/KCC2 ratio in the PFC at P14. Repeated exposures to sevoflurane in neonatal rather than juvenile rats enhanced the stress response and exacerbated neuroapoptosis in the PFC after exposed to electric foot shock in fear conditioning training. Neonatal rather than juvenile sevoflurane-exposed rats exhibited deficits in fear extinction training and recall. Pretreatment of neonatal rats prior to sevoflurane exposures with bumetanide reduced the NKCC1/KCC2 ratio at P14 and ameliorated most of the subsequent adverse effects. Our study indicates that repeated sevoflurane exposures in neonatal rats might increase the brain vulnerability to future stress exposure and resulted in fear extinction deficit, which might be associated with the neonatal enhanced brain depolarizing GABAAR activity.

The effect of remifentanil on the minimum alveolar concentration of isoflurane in children.

STUDY OBJECTIVE: To evaluate the effect of remifentanil on the isoflurane end-tidal concentration required to eliminate movement reaction upon surgical incision in children. DESIGN: Prospective, double blinded, serial study. SETTING: Operating room of a university-affiliated hospital. PATIENTS: Patients of ASA status 1 or 2, aged 4 to 7 years, scheduled for either inguinal hernia repair or orchidopexy surgery with general anesthesia. INTERVENTIONS AND MEASUREMENTS: After endotracheal intubation, 108 children serially received 1 of 6 dose (nil, 0.05, 0.10, 0.15, 0.20, or 0.25 µg kg(-1) min(-1)) of remifentanil. End-tidal isoflurane concentration was adjusted according to a Dixon's up-and-down approach. Twenty-five minutes after starting the remifentanil infusion, the surgical incision was performed. The response of patients was classified as either "response" or "no response." Response was defined as a purposeful response in response to skin incision. MAIN RESULTS: The MAC of isoflurane were 1.50 ± 0.16%, 1.33 ± 0.27%, 0.93 ± 0.13%, 0.73 ± 0.27%, 0.63 ± 0.19%, and 0.60 ± 0.15% for remifentanil infusion rates of nil, 0.05, 0.10, 0.15, 0.20, and 0.25 µg kg(-1) min(-1), respectively. CONCLUSION: The MAC of isoflurane decreased with increasing infusion rate of remifentanil, showing an initial step reduction followed by a ceiling effect.

Is muscle relaxant necessary in patients undergoing laparoscopic gynecological surgery with a ProSeal LMA™?

STUDY OBJECTIVE: To test the hypothesis that muscle relaxant is not necessary in patients who are undergoing laparoscopic gynecological surgery with a ProSeal Laryngeal Mask Airway (ProSeal LMA™). DESIGN: Prospective, randomized study. SETTING: Operating room of Sichuan Provincial Hospital for Women and Children. PATIENTS: 120 adult, ASA physical status 1 and 2 women, aged 18 to 55 years. INTERVENTIONS AND MEASUREMENTS: Patients were randomly assigned to two groups (n=60) to receive a muscle relaxant (Group MR) or not (Group NMR). General anesthesia was used in patients of both groups for airway management with the ProSeal LMA. Peak airway inflation pressures, airway sealing pressure, minimum flow rate, and recovery time were assessed. Surgical conditions were assessed by the operating gynecologist. The frequency of sore throats was recorded. MAIN RESULTS: ProSeal LMA insertion was 100% successful. Patients' lungs were ventilated with a maximum sealing pressure of 32 ± 5.1 cm H(2)O (Group MR) or 31 ± 4.9 cm H(2)O (Group NMR) (P = 0.341). The seal quality in both groups permitted the use of low flows: 485 ± 291 mL/min in Group MR and 539 ± 344 mL/min in Group NMR (P = 0.2). Surgical conditions were comparable between the two groups. There was no difference in the frequency of sore throats (20% vs 21.7%; P = 0.28). In Group NMR, there was a statistically significant reduction in recovery time versus Group MR (4.5 ± 2.6 min vs 10.3 ± 4.2 min; P < 0.01). CONCLUSION: Muscle relaxant is not necessary in general anesthesia with a ProSeal LMA.

The effect of nitrous oxide on intracuff pressure of the size 2 ProSeal Laryngeal Mask Airway.

STUDY OBJECTIVE: To investigate intracuff pressure changes in the ProSeal Laryngeal Mask Airway (PLMA) during 50% nitrous oxide (N2O) anesthesia. DESIGN: Prospective, randomized study. SETTING: Operating room of a university-affiliated hospital. PATIENTS: 40 ASA 1 and 2 children, aged 2 to 6 years, weighing 10-20 kg, undergoing elective inguinal herniorrhaphy with general anesthesia. INTERVENTIONS AND MEASUREMENTS: Patients were assigned to two groups (n = 20). Patients in Group A were anesthetized with 50% N(2)O in oxygen and sevoflurane, while patients in Group B were anesthetized with 50% air in oxygen and sevoflurane. PLMA cuffs were inflated with air. PLMA intracuff pressures starting from a baseline pressure of 30 mmHg were recorded using a pressure transducer for 30 minutes. The occurrence of postoperative throat discomfort was recorded. MAIN RESULTS: In Group A, who inhaled 50% N2O for 30 minutes, intracuff pressures reached 86.7 ± 10.4 mmHg, while in Group B, who inhaled 50% air for 30 minutes, intracuff pressures were 29.7 ± 1.0 mmHg. The postoperative throat complication rate in Group A was 45%, which was significantly higher than in Group B (5%). CONCLUSION: PLMA intracuff pressure increased significantly during 50% N2O anesthesia. The children's postoperative throat complication rate also was increased.