The effect on intraocular pressure of tracheal intubation or laryngeal mask™ insertion during sevoflurane anaesthesia in children without the use of muscle relaxants

BACKGROUND: We studied the effects of sevoflurane on intraocular pressure after induction in children undergoing either tracheal tube (TT) or laryngeal mask airway (LMA) insertion without a muscle relaxant METHODS: The study included 38 children. Anaesthesia was induced (8%) and maintained (3-4%) with sevoflurane in 100% O2. No muscle relaxant was used. A TT was inserted in group I (n=20), and an LMA in group II (n=18). IOPs were measured after induction, insertion of TT or LMA and at 1, 2 and 3 min thereafter. The heart rate, mean arterial pressures were also recorded. RESULTS: Intraocular pressures increased significantly in group I after TT (P < 0.01) and remained high until after 3 min. The pressures were similar in the LMA group at all measurements. CONCLUSION: Sevoflurane does not prevent the increase in IOP after intubation without muscle relaxants. LMA does not increase IOP in children after sevoflurane induction.     

Insertion of laryngeal mask airway does not increase the intraocular pressure in children with glaucoma

Objectives:  It is hypothesized that in children with glaucoma, the insertion of laryngeal mask airway (LMA) will cause lesser rise in intraocular pressure (IOP) than tracheal tube (TT). Aim:  To compare the IOP response to LMA and TT insertion in children with glaucoma. Methods/Materials:  A prospective, randomized, single‐blind study was conducted in 30 glaucomatous ASA‐1 children, aged 1–10 years scheduled to undergo trabeculectomy. Anesthesia was induced with halothane and maintained for 5 min with 1 MAC of halothane after administering atracurium 0.5 mg·kg^?1 following which LMA or TT was introduced. IOP was measured in both the eyes before and after insertion of airway device for 5 min. Results:  The IOP increased significantly from 27.3 ± 5.2 to 31.2 ± 5.4 mmHg (P < 0.001) after tracheal intubation but returned to baseline within 5 min. The IOP did not change from the baseline after insertion of LMA. The IOP was significantly higher in group TT compared to group LMA at 2 min (P = 0.004) and 5 min (P = 0.01) after the device insertion. The heart rate (HR) increased significantly after tracheal intubation and returned to baseline 4 min after intubation. The HR increase was significantly more in TT group compared to LMA group at all times of observation. Both systolic blood pressure (SBP; P = 0.01) and diastolic blood pressure (DBP; P = 0.02) showed an increase at 1 min in children in group TT. Conclusion:  Insertion of LMA in glaucomatous children is not associated with an increased IOP response or cardiovascular changes.     

Comparison of size 2 i-gel supraglottic airway with LMA-ProSeal™ and LMA-Classic™ in spontaneously breathing children undergoing elective surgery

Background: We compared size 2 i‐gel^® (Intersurgical Inc.), a relatively new supraglottic airway device for use in spontaneously breathing anesthesized children with two different types of laryngeal mask airway‐ProSeal? laryngeal mask airway (PLMA) and Classic? laryngeal mask airway (cLMA) for the ease of insertion, oropharyngeal sealing pressures (OSPs), and air leak. The hemodynamic effects on insertion of device and postoperative adverse effects were also noted. Methods: A randomized prospective study was planned in 120 children aged 2–5 years, weighing 10–20 kg, ASA physical status I–II scheduled for routine elective surgeries of <1‐h duration. They were randomly divided in three groups (i‐gel, PLMA, and cLMA) of 40 each, and a standard protocol for anesthesia was followed. Results: The age, weight, height, and type of surgery were similar in all groups. Success rate for first attempt was 95% for the i‐gel group and 90% for the two laryngeal mask airway groups. Insertion was found to be easy in the majority of cases in all groups, and there was no change in blood pressure, heart rate, or oxygen saturation on insertion. The OSP was 26 ± 2.6, 23 ± 1.2, and 22 ± 2.3 cm H₂O for i‐gel, PLMA, and cLMA, respectively. The difference between the i‐gel and both laryngeal mask airway groups was statistically significant (P < 0.01). There were no clinically important complications in the postoperative period. Conclusion: Pediatric size 2 i‐gel is easy to insert and provides higher OSP compared with same size PLMA and cLMA in spontaneously breathing children undergoing elective surgery. It may be a safe alternative to laryngeal mask airways in day care surgeries.     

Effect of tracheal intubation or laryngeal mask airway insertion on intraocular pressure using balanced anesthesia with sevoflurane and remifentanil.

STUDY OBJECTIVES: To study the effect of tracheal intubation or laryngeal mask airway (LMA) insertion on intraocular pressure (IOP) in strabismus patients undergoing balanced anesthesia with sevoflurane and remifentanil. DESIGN: Open, prospective, randomized study. SETTING: Tertiary care academic medical institution. PATIENTS: 40 adult ASA physical status I and II patients scheduled for elective strabismus surgery. INTERVENTION: Patients were randomized to receive either tracheal intubation or LMA insertion following mask induction with sevoflurane in combination with IV remifentanil. MEASUREMENTS: Intraocular pressure, mean arterial pressure (MAP), and heart rate (HR) were measured before induction, immediately following induction, and after airway insertion. MAIN RESULTS: Intraocular pressure after tracheal intubation or LMA insertion did not differ significantly from preoperative baseline values. Mean arterial pressure and HR did not significantly differ between groups at any time point. CONCLUSIONS: Remifentanil and sevoflurane are not associated with an increase in IOP response during tracheal intubation or LMA insertion above baseline in healthy patients undergoing ophthalmic surgery.     

The I‐gel®, a single‐use supraglottic airway device with a non‐inflatable cuff and an esophageal vent: an observational study in children

Background: The I‐gel^® is a new single‐use supraglottic airway device with a non‐inflatable cuff. It is composed of a thermoplastic elastomer and a soft gel‐like cuff that adapts to the hypopharyngeal anatomy. Like the LMA‐ProSeal, it has an airway tube and a gastric drain tube. Little is known about its efficiency in pediatric anesthesia. Methods: Fifty children above 30 kg, ASA I–II, undergoing a short‐duration surgery were included in this prospective, observational study. We evaluated ease in inserting the I‐gel^®, seal pressure, gastric leak, complications during insertion and removal, ease in inserting the gastric tube and ventilatory parameters during positive pressure ventilation. Results: All devices were inserted at the first attempt. The mean seal pressure was 25 cmH₂O. There was no gastric inflation and gastric tube insertion was achieved in all cases. The results appear similar to those in a previous study concerning laryngeal mask airway in terms of leak pressure and complication rates. Conclusion: Because the I‐gel^® has a very good insertion success rate and very few complications, it seems to be an efficient and safe device for pediatric airway management.     

Minimum alveolar concentration of desflurane with fentanyl for laryngeal mask airway removal in anesthetized children

Background: Desflurane provides rapid emergence from anesthesia. So, it can be used for the removal of a laryngeal mask airway in an anesthetized child. We conducted this study to determine the optimal endtidal concentrations of desflurane with fentanyl that would allow removal of a laryngeal mask airway without airway complication in children. Methods: Thirty‐six children of American Society of Anesthesiologist status I between 1 and 10 year of age undergoing ophthalmic surgery were recruited. General anesthesia was induced with sevoflurane and oxygen given via mask and laryngeal mask airway inserted. Anesthesia was maintained with desflurane in 100% oxygen. At the end of the surgery, predetermined target concentration was maintained for 10 min and laryngeal mask airway removed. Each target concentration at the time of removal was predetermined by the Dixon up–down method (with 0.5% as a step size) starting at 5% endtidal concentration. A removal accomplished without coughing, teeth clenching, gross purposeful movement, breath holding, or laryngospasm, during or within 1 min after removal, was considered to be successful. Results: Endtidal concentration of desflurane required for successful laryngeal mask airway removal in 50% (ED50) was 3.56% desflurane (95% confidence limits, 3.22–3.87%) along with fentanyl. Conclusion: Removal of laryngeal mask airway can be safely accomplished without coughing, moving, or any other airway complications at 3.57% endtidal concentrations of desflurane with fentanyl in 50% of anesthetized children.     

Efficacy of different concentrations of sevoflurane administered through a face mask for magnetic resonance imaging in children

Background: The main aim of this study was to use a non‐invasive method such as a face mask to maintain anesthesia in children during magnetic resonance imaging (MRI). The secondary aim was to ascertain hemodynamic‐respiration parameters, recovery time and complications of anesthesia with the administration of different concentrations of sevoflurane. Methods: This prospective and randomized study included 96 ASA I–II children, aged 1–10, scheduled to undergo MRI with anesthesia with sevoflurane through a face mask. All patients were administered midazolam 0.5 mg·kg^?1 orally 30 min before anesthesia induction. Sevoflurane 8% was given to induce anesthesia under assisted‐controlled ventilation for 2 min, and an intravenous route was opened on the hand. Three different concentrations of sevoflurane were administered through a face mask under spontaneous respiration to maintain anesthesia. A mixture of sevoflurane, oxygen, and air of 5 l·min^?1 was given through a face mask for anesthesia. Group 1 (n = 32) received 1.5% sevoflurane, Group 2 (n = 32) 1.25% sevoflurane, and Group 3 (n = 32) 1.0% sevoflurane. Recovery time, removal from the MRI room, postanesthesia care unit discharge data, and complications were also recorded. Heart rate, mean arterial pressure (MAP), peripheral oxygen saturation (SpO₂), respiration rate, and anesthesia adequacy were recorded every 5 min from the time of induction until completion of the MRI. Results: All three groups were similar in demographic and hemodynamic respiratory features. MRI was successfully performed in 96.6% of all patients without additional intervention. Sevoflurane concentrations were increased for a short time in one patient in Group 1 and in two patients in Group 3. Oxygen flow was increased in one patient in Group 1 and in one patient in Group 2 as SpO₂ was lower than 95%. The mean time to eye opening (from discontinuation of sevoflurane to eye opening) was 155.8 ± 50.0 s in Group 1, 89.5 ± 16.0 s in Group 2, and 53.5 ± 10.0 s in Group 3; differences between the groups were statistically significant (P = 0.001). Airways were not used on any of the patients, and none vomited or required endotracheal intubation or laryngeal mask anesthesia. Conclusions: We believe that the administration of sevoflurane at a concentration of 1% via a face mask under spontaneous respiration may provide light anesthesia without complications to induce an unarousable sleep for children during MRI.     

A clinical evaluation of the i‐gelTM supraglottic airway device in children

Background: The i‐gel^TM is one of the latest commercially available, second‐generation supraglottic airway devices (SADs). Specific features include a distal cuff made of a thermoplastic elastomer gel that does not require inflation and a gastric side channel to allow passage of a gastric tube, venting of gas from the stomach, and an early indication of regurgitation. Previous studies in older children and adults have shown that it is a reliable, efficient, and safe device for airway management. Methods: We evaluated the i‐gel^TM in sizes ranging from 1 to 2.5 in children considered suitable for a supraglottic device. We assessed successful rates of insertion, airway leak pressure, position confirmed by fiberoptic laryngoscopy, gastric tube placement, manipulations required, and complications. Results: The i‐gel^TM was used in 154 children over a period of 12 months. The median age [interquartile range (IQR)] was 4 years 11 months (2–7 years), median weight (IQR) 19 kg (13–26), and median (IQR) duration of procedure 29 (30–45) min. First insertion attempt was successful in 93.5% of patients, and second attempt in 5.8%. The median (IQR) time to insertion was 14 (13–16) s. The median (IQR) leak pressure was 20 (15–25) cmH₂0. Gastric tube placement was successful in 90% of cases. On fiberoptic examination, the vocal cords were visible in 97% of patients. Complications arose in 20% of patients, but the majority were minor. Anesthetists commented that the device had a tendency to displace upward out of the mouth and that extension toward the forehead and flexion toward the feet of the proximal tube altered the quality of the airway. Overall, in seven (4.5%) patients, the device was abandoned and an alternative airway was used. Conclusions: Pediatric i‐gel^TM sizes 1.5–2.5 provided a satisfactory airway during anesthesia for spontaneously breathing infants and children. However, to ensure a clear airway, considerable vigilance is required when fixing the device in the mouth and to avoid the negative effects of flexion of the proximal tubing. The i‐gel^TM is more expensive than first‐generation devices. Whether this additional cost for the potential benefit of greater airway protection is considered acceptable will depend on longer‐time evaluation and surveillance to establish overall safety.     

A comparison of the i‐gel™ and the PRO‐Breathe® laryngeal mask during pressure support ventilation in children

Many studies comparing the i‐gel^? with laryngeal masks include patients in whom laryngeal mask cuff inflation pressures are higher than recommended, or involve the use of neuromuscular blocking drugs and positive pressure ventilation. We compared the i‐gel with the PRO‐Breathe^® laryngeal mask in anaesthetised, spontaneously breathing children. Two hundred patients aged up to 16 years were randomly allocated to either the i‐gel or the PRO‐Breathe laryngeal mask. The PRO‐Breathe was inflated to an intracuff pressure of 40 cmH₂O. All patients received pressure support of 10 cmH₂O and positive end‐expiratory pressure of 5 cmH₂O. Successful insertion at the first attempt was 82% for the i‐gel compared with 93% for the PRO‐Breathe (p = 0.019). Leakage volume was significantly higher with i‐gel sizes 1.5 (p = 0.015), 2 (p = 0.375), 2.5 (p = 0.021) and 3 (p = 0.003) compared with the equivalent‐sized PRO‐Breathe device. Device dislodgement following successful initial placement was more frequent with the i‐gel (5%) compared with the PRO‐Breathe laryngeal mask (0%). We conclude that the PRO‐Breathe laryngeal mask is superior to the i‐gel in terms of leakage volume and device dislodgement.     

不同麻醉方法对小儿腹腔镜疝修补术后免疫功能的影响

目的探讨七氟醚吸入喉罩全麻与骶管阻滞复合七氟醚吸入喉罩全麻2种全身麻醉对小儿斜疝腹腔镜术后机体特异性细胞免疫功能的影响。 方法前瞻性选择2015年1月至2017年6月,东莞市妇幼保健院进行治疗的小儿斜疝100例,将其按随机数字表法分为试验组和对照组,每组50例。其中试验组采用骶管阻滞复合七氟醚吸入喉罩全麻法,对照组采用七氟醚吸入喉罩全麻法。统计学分析2组患儿斜疝腹腔镜手术中不同麻醉方法对机体细胞免疫功能的影响。 结果2组术后2、24 h CD3⁺,CD4⁺,CD4⁺/CD8⁺值均较麻醉前降低,但对照组下降更为显著,差异有统计学意义（P<0.05）,试验组差异无统计学意义（P>0.05）;2组CD8⁺值前后变化较小,差异无统计学意义（P>0.05）。术后24 h对照组CD3⁺,CD4⁺,CD4⁺/CD8⁺值均显著低于试验组术后24 h各个指标水平,差异有统计学意义（P<0.05）。与麻醉前比较,两组术后24 h、72 h的IL-10水平均显著升高,差异有统计学意义（P<0.05）。 结论骶管阻滞复合七氟醚吸入喉罩全麻对小儿斜疝腹腔镜术后机体特异性细胞免疫功能的影响较小,对于免疫功能相对低下的患儿有利于术后恢复。     

A cohort evaluation of the Laryngeal Mask Airway‐Supreme™ in children

Objectives: To assess the clinical performance of the laryngeal mask airway‐Supreme in children. Aim: The purpose of this prospective audit was to evaluate the feasibility of the laryngeal mask airway‐Supreme in clinical practice and generate data for future comparison trials. Background: The laryngeal mask airway‐Supreme is a new second‐generation supraglottic airway that was recently released in limited pediatric sizes (sizes 1, 2). Methods: One hundred children, ASA I‐III, newborn to 16 years of age, and undergoing various procedures requiring a size 1, 2, or 3 laryngeal mask airway‐Supreme were studied. Assessments included insertion success rates, airway leak pressures, success of gastric tube insertion, quality of airway, and perioperative complications. Results: The first‐time insertion success rate was 97%, with an overall insertion success rate of 100%. The mean initial airway leak pressure for all patients was 22.3 ± 6.6 cm H₂O. Gastric tube placement was possible in 98% of patients. Complications were noted in six patients: coughing or laryngospasm (n = 3), sore throat (n = 1), and dysphonia (n = 2). Conclusions: The laryngeal mask airway‐Supreme was inserted with a high degree of success on the first attempt by clinicians with limited prior experience with the device. It was effectively used for a variety of procedures in children undergoing spontaneous and mechanical ventilation with minimal complications. The leak pressures demonstrated in this study, along with access for gastric decompression, suggest that the laryngeal mask airway‐Supreme may be an effective device for positive pressure ventilation in children.     

Recovery and pharmacokinetic parameters of desflurane, sevoflurane, and isoflurane in patients undergoing urologic procedures.

STUDY OBJECTIVE: To compare the pharmacokinetics and the speed of recovery after inhalation anesthesia with desflurane, sevoflurane, and isoflurane in elective surgery. DESIGN: Prospective, randomized study. SETTING: University medical center. PATIENTS: 30 ASA physical status I and II adults presenting for elective surgery. INTERVENTIONS: Anesthesia was induced with etomidate and maintained with desflurane (n = 10), sevoflurane (n = 10), or isoflurane (n = 10) and nitrous oxide. The inhalation drugs were titrated until an adequate clinical depth of anesthesia was reached. At the end of anesthesia, the patients breathed oxygen via the endotracheal tube and after extubation via a face mask. MEASUREMENTS AND MAIN RESULTS: The groups were similar with respect to age, weight, duration of anesthesia, and mean arterial pressure. Mean end-tidal concentration (FA = FA0) at the end of anesthesia was 6.34 +/- 1.15% after desflurane, 1.85 +/- 0.42% after sevoflurane, and 1.10 +/- 0.24% after isoflurane. FA/FA0 decreased significantly faster with desflurane than with isoflurane, while there was little difference between desflurane and sevoflurane. As for the terminal half-life (t1/2), there were no differences among the groups (8.16 +/- 3.15 min after desflurane, 9.47 +/- 4.46 min after sevoflurane, and 10.0 +/- 5.57 min after isoflurane). The time until a command was followed for the first time was the same in all three groups (13.0 +/- 4.7 min after desflurane, 13.4 +/- 4.4 min after sevoflurane, and 13.6 +/- 3.4 min after isoflurane). There was no significant correlation between duration of anesthesia and the time until recovery. CONCLUSIONS: There are only minor differences with regard to the recovery phase in premedicated patients who receive clinically titrated inhalation anesthesia with desflurane, sevoflurane, or isoflurane.     

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

Background: Both over‐ and undercorrection can occur in up to 10–15% of strabismus surgeries. Use of adjustable suture technique and an intraoperative awake test may decrease the incidence of over‐ or undercorrection. In this study, we investigated the ability to provide optimal conditions for intraoperative awake strabismus suture adjustment in children by means of target‐controlled infusions (TCI) of propofol and remifentanil propofol compared with propofol and sufentanil. Methods: Forty‐six ASA I–II patients undergoing strabismus surgery with intraoperative awakening were randomly assigned to anesthesia by TCI of propofol + sufentanil group (group SF) or propofol + remifentanil spontaneous breathing. Propofol was discontinued, and concentrations of the opioid TCIs were reduced to enable awake assessment of the mobility and position of the eye. Changes in intraocular pressure, respiratory function, hemodynamics, awakening time, and awaking quality were compared between the two groups. The degrees of sedation and analgesia were evaluated through the assessment of alertness and sedation scores (OAA/S) and visual analog scale scores (VAS). Results: There was no significant difference in intraocular pressure at three sampling points between two groups (P > 0.05). The heart rate (HR) and mean arterial blood pressure (MAP) in group SF were significantly lower than group RF during laryngeal mask insertion (P < 0.05) as well as during the wake‐up test (P < 0.05). Spontaneous breathing was maintained in all patients, and there was no significant difference in RR and Sp02 at T1–T11 between the groups (P > 0.05). There was no significant difference in the target effect‐site concentration of propofol at T1–T10 between the groups (P > 0.05). The wake‐up times in group SF were significantly longer than in group RF (P < 0.05). In contrast, the quality of wake‐up test and the degree of consciousness after the patients were awakened were significantly better (19 good and 4 satisfactory vs 15 good, 2 satisfactory, and 6 poor) in SF group than RF group. The VAS was significantly lower at T6–T9 in SF group than in RF group (P < 0.05). The incidence of untoward events during and after surgery, such as respiratory depression and apnea, oculocardiac reflex, coughing, groan and nausea, and vomiting was not significantly different between the groups (P > 0.05). Conclusion: Propofol combined with sufentanil or remifentanil can be suitable for planned intraoperative awakening for an adjustable suture technique in pediatric patients during strabismus surgery. Remifentanil has quicker wake‐up time; however, sufentanil demonstrated an advantage in terms of better analgesia, more stable hemodynamics, and improved qualify of awakening.     

Efficacy of ketamine and midazolam as co-induction agents with propofol for laryngeal mask insertion in children

Objectives: Use of midazolam and ketamine lowers the induction dose of propofol (co‐induction) producing hemodynamic stability. Background: Large doses of propofol needed for induction and laryngeal mask (LM) insertion in children may be associated with hemodynamic and respiratory effects. Co‐induction has the advantage of reducing dose and therefore maintaining hemodynamic stability. Aim: To examine the effect of co‐induction on hemodynamics, LM insertion and recovery in children. Methods/Materials: A prospective, randomized, double‐blind, controlled study was conducted in 60 ASA I/II children, age 1–8 years. Normal saline, ketamine 0.5 mg·kg^?1, midazolam 0.05 mg·kg^?1 were administered in groups P (propofol), PK (propofol–ketamine) and PM (propofol–midazolam), respectively, 2 min prior to the administration of the induction dose of propofol. Propofol 3.5 mg·kg^?1 (group P) or 2.5 mg·kg^?1 (groups PK and PM) was used for induction, LM inserted 30 s later and insertion conditions assessed. Heart rate and blood pressure were recorded immediately after propofol bolus, then every min till 2 min after LMA insertion. Recovery was assessed using Steward’s Score. Result: In group P, systolic blood pressure (SBP) showed a significantly greater decrease compared to group PK and group PM (P < 0.005). Only 5% of patients in groups PK and PM showed >20% fall in SBP compared to 89% in group P (P < 0.005). More children in groups PK and PM had acceptable conditions for LM insertion compared to group P (P < 0.05). The time to achieve Steward Score of 6 was longer in groups PK and PM compared to group P (P < 0.005). Conclusion: In children, the combination of propofol with ketamine or midazolam produces stable hemodynamics and improved LM insertion conditions but is associated with delayed recovery.     

Airway reflexes return more rapidly after desflurane anesthesia than after sevoflurane anesthesia

Patients given a more soluble inhaled anesthetic usually take longer to awaken from anesthesia than do patients given a less soluble anesthetic. In the present study, we tested whether such a delay in awakening was also associated with a delay in restoration of protective airway reflexes. Patients were randomly assigned to receive desflurane (n = 31) or sevoflurane (n = 33) via a laryngeal mask airway. Demographics did not differ between groups. The average minimum alveolar anesthetic concentration fraction for both groups was 0.62, and the mean (+/-sd) minimum alveolar anesthetic concentration hours was 1.00 +/- 0.68 for desflurane versus 0.95 +/- 0.57 for sevoflurane, although more patients given sevoflurane also received regional anesthesia (17 for sevoflurane and 8 for desflurane). The time from stopping anesthetic administration to appropriate response to command was longer after sevoflurane (5.5 +/- 3.1 versus 3.4 +/- 1.9 min; P < 0.01). In addition, the time from first response to command to ability to swallow 20 mL of water without coughing or drooling was longer after sevoflurane. At 2 min after responding to command, all patients given desflurane were able to swallow without coughing or drooling, whereas 55% of patients given sevoflurane coughed and/or drooled (P < 0.001). At 6 min after responding to command, 18% of patients given sevoflurane still could not swallow without coughing or drooling (P < 0.05). We conclude that desflurane allows an earlier return of protective airway reflexes.     

A systematic review and meta‐analysis of the i‐gel® vs laryngeal mask airway in adults

We systematically reviewed 31 adult randomised clinical trials of the i‐gel^® vs laryngeal mask airway. The mean (95% CI) leak pressure difference and relative risk (95% CI) of insertion on the first attempt were similar: 0.40 (?1.23 to 2.02) cmH₂O and 0.98 (0.95–1.01), respectively. The mean (95% CI) insertion time and the relative risk (95% CI) of sore throat were less with the i‐gel: by 1.46 (0.33–2.60) s, p = 0.01, and 0.59 (0.38–0.90), p = 0.02, respectively. The relative risk of poor fibreoptic view through the i‐gel was 0.29 (0.16–0.54), p < 0.0001. All outcomes displayed substantial heterogeneity, I² ≥ 75%. Subgroup analyses did not decrease heterogeneity, but suggested that insertion of the i‐gel was faster than for first‐generation laryngeal mask airways and that the i‐gel leak pressure was higher than first generation, but lower than second‐generation, laryngeal mask airways. A less frequent sore throat was the main clinical advantage of the i‐gel.     

Inhalation anaesthesia is cost-effective for ambulatory surgery: a clinical comparison with propofol during elective knee arthroscopy

BACKGROUND AND OBJECTIVE: Cost consciousness has become increasingly important in anaesthesia as elsewhere in healthcare. Cost-minimization with uncompromised patient safety and quality requires systematic comparisons of alternative techniques. Inhalation anaesthesia with desflurane or sevoflurane is compared in this study with propofol delivered by the target controlled infusion technique. Directly measured drug consumption and costs and emergence times are compared. METHODS: Consumed anaesthetics were measured during elective arthroscopy of the knee, and costs were calculated for ASA I-II patients (n = 102) randomized to 3 groups: one group received anaesthesia using propofol administered by target controlled infusion, the others inhalation anaesthesia with either desflurane or sevoflurane in combination with nitrous oxide. A partial rebreathing system was used with a laryngeal mask airway. Vaporizers were weighed before and after each anaesthetic. RESULTS: Anaesthetic duration, postoperative pain and emesis as well as discharge time did not differ between groups. Inhaled anaesthetic techniques with desflurane or sevoflurane were associated with 2-3 min shorter emergence times (P < 0.001) and approximately 45% lower cost for consumed anaesthetics as compared with a propofol technique based on target controlled infusion. The inclusion of waste costs improved the cost reduction to 55%. CONCLUSIONS: For this patient group, use of inhalation anaesthesia reduced drug costs by half and shortened emergence times compared to target controlled infusion with propofol with equal perioperative patient conditions.     

Conventional stepwise vs. vital capacity rapid inhalation induction at two concentrations of sevoflurane

BACKGROUND AND OBJECTIVE: A multicentre study was conducted to compare three methods of inhalation induction with sevoflurane in adult premedicated patients. METHODS: One-hundred-and-twenty-five adult patients of ASA I-II were scheduled for short elective surgical procedures (< 90 min) under general anaesthesia with spontaneous ventilation of the lungs via a laryngeal mask airway. Patients were randomly assigned to one of three groups: conventional stepwise inhalation induction group (Group C) or vital capacity rapid inhalation induction groups at 4.5% (Group VC4.5) or at 8% sevoflurane (Group VC8). Before anaesthetic induction, fentanyl 1 micro kg(-1) was given and the face mask applied with the anaesthetic breathing system primed with sevoflurane 4.5% or 8% in the respective vital capacity groups. Loss of eyelash reflex, time to cessation of finger tapping, laryngeal mask insertion, side-effects and adequacy of induction were recorded. RESULTS: The time to loss of eyelash reflex was significantly shorter in both vital capacity groups vs. the control group: VC8: 68 +/- 7 s; and VC4.5: 94 +/- 6.5 s vs. C: 118 +/- 6.4s (P < 0.0001). Significant differences were found in all pairwise comparisons for time to cessation of tapping: Group VC8 (62 +/- 7 s), Group VC4.5 (85 +/- 6 s) and Group C (116 +/- 6 s; P < 0.0001). The time to laryngeal mask insertion was significantly shorter in the Group VC8 (176 +/- 13 s) compared with the other two groups, Group VC4.5 (219 +/- 13 s) and Group C (216 +/- 9 s). There were no significant differences in the incidence of side-effects between the three groups. CONCLUSIONS: Inhalation induction of anaesthesia with sevoflurane with the three techniques tested is safe, reliable and well accepted by the patients. The vital capacity rapid inhalation group primed with sevoflurane 8% was the fastest method with no relevant side-effects.     

Optimization of desflurane administration in morbidly obese patients: a comparison with sevoflurane using an 'inhalation bolus' technique

Background. The concept of an ‘inhalation bolus’can be used to optimize inhaled drug administration. We investigatedthe depth of anaesthesia, haemodynamic stability, and recoverytime in morbidly obese patients resulting from bispectral index^TM(BIS^TM)-guided sevoflurane or desflurane administration andBIS-triggered inhalation boluses of sevoflurane or desfluranecombined with titration of remifentanil. Methods. Fifty morbidly obese patients undergoing laparoscopicgastroplasty received either BIS-guided sevoflurane or desfluraneanaesthesia in combination with a remifentanil target-controlledinfusion. Intraoperative haemodynamic stability and BIS controlwere measured. Immediate recovery was recorded. Results. Intraoperatively, the BIS was between 40 and 60 fora greater percentage of time in the sevoflurane (78 (13)% ofcase time) than in the desflurane patients (64 (14)% of casetime), owing to too profound anaesthesia in the desflurane patientsat the start of the procedure. However, fewer episodes of hypotensionwere found in the desflurane group, without the occurrence ofmore hypertensive episodes. During immediate recovery, eye opening,extubation, airway maintenance, and orientation occurred soonerin the desflurane group. Conclusions. Immediate recovery was significantly faster inthe desflurane group. Overall hypnotic controllability measuredby BIS was less accurate with desflurane. Overall haemodynamiccontrollability was better when using desflurane. Fewer episodesof hypotension were found in the desflurane group. The use ofthe inhalation bolus was found to be appropriate in both groupswithout causing severe haemodynamic side effects. Minimal BISvalues were significantly lower after a desflurane bolus. Br J Anaesth 2003; 91: 638–50     

对比七氟醚喉罩吸入麻醉与异丙酚静脉麻醉在小儿腹股沟斜疝手术中的应用

目的对比七氟醚喉罩吸入麻醉与异丙酚静脉麻醉在小儿腹股沟斜疝手术中的应用。 方法选取2017年1月至2018年1月,东部战区总医院收治的小儿腹股沟斜疝患儿100例,按麻醉方案的不同将其分为对照组和观察组,每组50例。对照组给予异丙酚静脉麻醉,观察组给予七氟醚喉罩吸入麻醉。比较2组麻醉效果,不同时间点的平均动脉压（MAP）、心率（HR）和血氧饱和度（SpO₂）的变化及2组拔管后不良反应。 结果观察组的意识消失时间、诱导至插管时间、苏醒时间、拔喉罩时间、离开麻醉恢复室时间均短于对照组,差异有统计学意义（P<0.05）。T1～T3时2组MAP和对照组HR比较,差异有统计学意义（P<0.05）,T1～T3时2组MAP和HR均呈现升高趋势（P<0.05）,且T2、T3时对照组MAP和HR高于观察组（P<0.05）;2组SpO₂在T1～T3无差异（P>0.05）;观察组和对照组苏醒后的不良反应发生率分别为4.00%、16.00%,且观察组的不良反应发生率低于对照组（P<0.05）。 结论小儿腹股沟斜疝手术中七氟醚喉罩吸入麻醉可以使患儿生命体征平稳,术后不良反应较少,且麻醉效果优于异丙酚静脉麻醉。