The effect of low-flow sevoflurane and desflurane on pulmonary mechanics during laparoscopic surgery

Effects of dexmedetomidine on dynamic lung compliance in general anesthesia with desflurane: A randomized controlled study

Objective

The aim of this study was to evaluate the effect of dexmedetomidine on lung compliance in patients under general anesthesia with desflurane.

Methods

This prospective, randomized, double-blind, controlled trial included 51 patients who received general anesthesia undergoing lower limb fracture surgery. Participants were assigned to either the experimental (loading dose of 0.25 μg/kg dexmedetomidine over 10 min, followed by a maintenance dose of 0.3 μg/kg/h until the end of the surgery) or control (0.9% saline) group. Anesthesia was maintained with desflurane, analgesics and muscle relaxants. The two groups were compared for hemodynamic parameters, dynamic lung compliance, oxygenation index, and postoperative complications.

Results

While dynamic lung compliance showed no significant difference between the two groups at T1 (P = 0.321), it was significantly higher in the experimental group at all other time points (all P < 0.001). In the control group, Cdyn at T4, T5, T6, and T7 were lower than that at T1 (P = 0.032, 0.043, 0.032 and 0.018, respectively). There were no significant between-group differences in the mean arterial pressure and heart rate. Compared to the control group, the experimental group had a higher oxygenation index at T1 (P < 0.001), T2 (P < 0.001), T3 (P < 0.001), T4 (P = 0.02), and T5 (P = 0.016) and significantly lower peak airway pressure at all time points (all P < 0.001). Both groups had comparable postoperative outcomes.

Conclusions

Dexmedetomidine infusion at a loading dose of 0.25 μg/kg and maintenance dose of 0.3 μg/kg/h improved dynamic lung compliance in patients receiving desflurane during general anesthesia.

Temporal Changes in Ventilator Settings in Patients With Uninjured Lungs: A Systematic Review

In patients with uninjured lungs, increasing evidence indicates that tidal volume (VT) reduction improves outcomes in the intensive care unit (ICU) and in the operating room (OR). However, the degree to which this evidence has translated to clinical changes in ventilator settings for patients with uninjured lungs is unknown. To clarify whether ventilator settings have changed, we searched MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science for publications on invasive ventilation in ICUs or ORs, excluding those on patients <18 years of age or those with >25% of patients with acute respiratory distress syndrome (ARDS). Our primary end point was temporal change in VT over time. Secondary end points were changes in maximum airway pressure, mean airway pressure, positive end-expiratory pressure, inspiratory oxygen fraction, development of ARDS (ICU studies only), and postoperative pulmonary complications (OR studies only) determined using correlation analysis and linear regression. We identified 96 ICU and 96 OR studies comprising 130,316 patients from 1975 to 2014 and observed that in the ICU, VT size decreased annually by 0.16 mL/kg (-0.19 to -0.12 mL/kg) (P < .001), while positive end-expiratory pressure increased by an average of 0.1 mbar/y (0.02-0.17 mbar/y) (P = .017). In the OR, VT size decreased by 0.09 mL/kg per year (-0.14 to -0.04 mL/kg per year) (P < .001). The change in VTs leveled off in 1995. Other intraoperative ventilator settings did not change in the study period. Incidences of ARDS (ICU studies) and postoperative pulmonary complications (OR studies) also did not change over time. We found that, during a 39-year period, from 1975 to 2014, VTs in clinical studies on mechanical ventilation have decreased significantly in the ICU and in the OR.

The Effect of sevoflurane, desflurane and propofol on respiratory mechanics and integrated pulmonary index scores in laparoscopic sleeve gastrectomy. A randomized trial

Objectives:

To compare the effects of sevoflurane, desflurane, and propofol on respiratory mechanics, and integrated pulmonary index (IPI) scores in patients undergoing laparoscopic sleeve gastrectomy.

Methods:

A total of 60 patients with a body mass index of ≥40 kg/m², who underwent laparoscopic sleeve gastrectomy between September 2015 and September 2016 at Fatih Sultan Mehmet Health Application and Research Center, Istanbul, Turkey were included in this randomized prospective study. After induction, anesthesia was maintained by sevoflurane in group S, desflurane in group D, and propofol in group P. Peak inspiratory pressure (PIP), plateau pressure (P_plateau), compliance (Cdyn), respiratory resistance (Rrs), and IPI values were recorded. Mann-Whitney U, Kruskal-Wallis, Dunn’s, Friedman, and Fisher-Freeman-Halton tests were performed for statistical analysis. A p value of <0.05 was considered statistically significant.

Results:

A significant increase was found in PIP in group S (T₁: 25; T₂: 27 cmH₂O), and group D (T₁: 25; T₂: 29,5 cmH₂O) during pneumoperitoneum. Dynamic compliance decreased in all groups during pneumoperitoneum. In group S, the decrease in Cdyn was also statistically significant after pneumoperitoneum (T₁: 43.65; T₅: 41.25 ml/cmH₂O). Comparison between groups the values of PIP, P_plateau, Cdyn, Rrs, and IPI were similar.

Conclusion:

In morbidly obese patients, sevoflurane, desflurane, and propofol are similar in terms of the intraoperative respiratory mechanics, and perioperative respiratory parameters provided with IPI.

Comparison of the Level of Free Hexafluoro-isopropanol in Adults' Blood and the Incidence of Emergence Agitation After Anesthesia With Different Concentrations of Sevoflurane in Laparoscopic Gastrointestinal Surgery: A Randomized Controlled Clinical Trial

PURPOSE

The aim of the study is to compare the free hexafluoro-isopropanol (HFIP) concentration in adults' blood and the incidence of emergence agitation (EA) after inhaled different concentrations of sevoflurane.

METHODS

Sixty adult patients planning to undergo laparoscopic gastrointestinal surgery were randomly assigned to 3 groups. Each group received sevoflurane as the volatile anesthetic at different concentrations: 0.5 minimum alveolar concentration (MAC), 1.0 MAC, and 1.5 MAC. The use of sevoflurane was continued until the end of surgery. Venous blood samples were obtained at 30, 60, 120, and 180 minutes after starting the use of sevoflurane and subsequently at 60, 180, and 300 minutes after discontinuation of volatile anesthetic administration. Blood concentrations of sevoflurane and free HFIP were determined using gas chromatography. The recovery time and the incidence of EA at different time points were evaluated among the 3 groups.

FINDINGS

Changes in the blood concentrations of sevoflurane and free HFIP during and after the use of sevoflurane were similar in all 3 groups. The peak blood concentration of free HFIP occurred 60 minutes after onset of sevoflurane anesthesia in all 3 groups (P < 0.05). The lowest level of free HFIP and the longest recovery time were found in the 1.5-MAC group (P < 0.05). No significant difference was found in the incidence of EA or moderate pain among the 3 groups during recovery.

IMPLICATIONS

The generation of HFIP would be inhibited when the inhaled sevoflurane concentration increased to 1.5 MAC. However, the incidence of EA during recovery had nothing to do with the inhaled different sevoflurane concentrations (within 1.5 MAC) in adults. ChicCTR.org identifier: ChiCTR-IPD-17011558.

Effects of Low-Flow Sevoflurane Anesthesia on Pulmonary Functions in Patients Undergoing Laparoscopic Abdominal Surgery

Objective. The aim of this prospective, randomized study was to investigate the effects of low-flow sevoflurane anesthesia on the pulmonary functions in patients undergoing laparoscopic cholecystectomy. Methods. Sixty American Society of Anesthesiologists (ASA) physical status classes I and II patients scheduled for elective laparoscopic cholecystectomy were included in the study. Patients were randomly allocated to two study groups: high-flow sevoflurane anesthesia group (Group H, n = 30) and low-flow sevoflurane anesthesia group (Group L, n = 30). The fresh gas flow rate was of 4 L/min in high-flow sevoflurane anesthesia group and 1 L/min in low-flow sevoflurane anesthesia group. Heart rate (HR), mean arterial blood pressure (MABP), peripheral oxygen saturation (SpO₂), and end-tidal carbon dioxide concentration (ETCO₂) were recorded. Pulmonary function tests were performed before and 2, 8, and 24 hours after surgery. Results. There was no significant difference between the two groups in terms of HR, MABP, SpO₂, and ETCO₂. Pulmonary function test results were similar in both groups at all measurement times. Conclusions. The effects of low-flow sevoflurane anesthesia on pulmonary functions are comparable to high-flow sevoflurane anesthesia in patients undergoing laparoscopic cholecystectomy.

Hemodynamic parameters of low-flow isoflurane and low-flow sevoflurane anesthesia during controlled ventilation with laryngeal mask airway

Background:

Nowadays laryngeal mask airway (LMA) is popular as one of the best choices for airway management. Low-flow anesthesia has some advantages like lower pollution, hemodynamic stability and cost effectiveness. Volatile anesthetics are widely used for anesthesia maintenance during operations. Sevoflurane has more hemodynamic stability compared to isoflurane, but there are few studies comparing the hemodynamic stabilities of these two anesthetics during controlled low flow anesthesia with LMA.

Objectives:

The aim of this study was to compare the effects of low-flow sevoflurane and low-flow isoflurane on hemodynamic parameters of patients through LMA.

Patients and Methods:

Eighty patients, scheduled for elective ophthalmic surgery, were randomly divided into two groups. After induction, an LMA with an appropriate size was inserted in all the patients and they were randomly allocated to two groups of low-flow sevoflurane (n = 40) and low-flow isoflurane (n = 40). Hemodynamic parameters (heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and Mean Arterial Pressure (MAP) were recorded at 5, 10, 15, 20, 25 and 30 minutes after the anesthesia induction.

Results:

The mean heart rate values were significantly less in the sevoflurane group (P value < 0.05) at 25 minutes after the surgery. The mean Blood Pressure in the isoflurane group was significantly higher compared with the sevoflurane group in 10, 20 and 30 minutes after the surgery (P values = 0.0131, 0.0373 and 0.0028, respectively). These differences were clinically unimportant because heart rate and mean blood pressure were on normal ranges.

Conclusions:

Seemingly, low-flow sevoflurane with LMA did not have any significant hemodynamic effect on clinical practice. Therefore, low-flow sevoflurane anesthesia with LMA might be considered in patients with short operations who need rapid recovery from anesthesia.

Comparison of respiratory mechanics between sevoflurane and propofol-remifentanil anesthesia for laparoscopic colectomy

BACKGROUND

The creation of pneumoperitoneum and Trendelenburg positioning during laparoscopic surgery are associated with respiratory changes. We aimed to compare respiratory mechanics while using intravenous propofol and remifentanil vs. sevoflurane during laparoscopic colectomy.

METHODS

SIXTY PATIENTS UNDERGOING LAPAROSCOPIC COLECTOMY WERE RANDOMLY ALLOCATED TO ONE OF THE TWO GROUPS: group PR (propofol-remifentanil group; n = 30), and group S (sevoflurane group; n = 30). Peak inspiratory pressure (PIP), dynamic lung compliance (Cdyn), and respiratory resistance (Rrs) values at five different time points: 5 minutes after induction of anesthesia (supine position, T1), 3 minutes after pneumoperitoneum (lithotomy position, T2), 3 minutes after pneumoperitoneum while in the lithotomy-Trendelenburg position (T3), 30 minutes after pneumoperitoneum (T4), and 3 minutes after deflation of pneumoperitoneum (T5).

RESULTS

In both groups, there were significant increases in PIP and Rrs while Cdyn decreased at times T2, T3, and T4 compared to T1 (P < 0.001). The Rrs of group PR for T2, T3, and T4 were significantly higher than those measured in group S for the corresponding time points (P < 0.05).

CONCLUSIONS

Respiratory mechanics can be adversely affected during laparoscopic colectomy. Respiratory resistance was significantly higher during propofol-remifentanil anesthesia than sevoflurane anesthesia.

Bispectral index and cerebral oximetry in low-flow and high-flow rate anaesthesia during laparoscopic cholecystectomy - a randomized controlled trial

Introduction

The need to reduce pollution emissions in the operating room and to reduce treatment costs motivates more frequent use of general anaesthesia with a small or minimal fresh gas flow rate. Nevertheless, the reduction of the delivery of fresh gases should not influence the quality and safety of the anaesthesia.

Material and methods

A total of 105 elective laparoscopic cholecystectomy patients were included in the study. There were 72 female (68.6%) and 33 male (31.4%) patients. Patients were randomized by a ‘closed envelope’ method into two groups. Group I included patients with low-flow anaesthesia and group II included patients with high-flow anaesthesia. In all patients the cerebral oximetry was measured separately for each cerebral hemisphere; the bispectral index (BIS), heart rate, blood pressure, end-tidal carbon dioxide concentration and haemoglobin oxygen saturation were monitored.

Results

Heart rate, blood pressure, end-tidal carbon dioxide concentration and saturation were similar in both groups and the differences between them were statistically insignificant. The BIS values were similar in both groups and indicated that patients who underwent low-flow anaesthesia were not exposed to a higher risk of awakening during the procedure than the high-flow anaesthesia patients. The changes in brain oximetry values were similar in both low-flow and high-flow anaesthesia.

Conclusions

Use of both low-flow and high-flow rate general anaesthesia provided patients undergoing laparoscopic cholecystectomy proper oxygenation of the central nervous system, adequate sleep depth and haemodynamic stability.

Biochemical Effects of Low-Flow Anesthesia with Inhalation agents in Patients undergoing Laparoscopic Surgery

This study was designed to investigate the effects of low-flow anesthesia with sevoflurane and desflurane on renal and hepatic functions in patients undergoing laparoscopic abdominal surgery. Twenty patients with ASA I or II (American Society of Anesthesiologists classification) physical scores were included in the study. There were no significant differences between sevoflurane and desflurane groups with respect to age, weight, body mass index, duration of the operation and the anesthesia. In both groups, renal function parameters such as urea, BUN, creatinine and calculated creatinine clearance did not show significant differences at 24 and 48 hours. Homocysteine levels, which showed renal metabolic function, did not change significantly at 24 and 48 hours when compared to baseline levels in both groups. Transaminases were not significantly different between the two groups from baseline to 24 and 48 hours. These differences between the preoperative and postoperative values of biochemical parameters were similar for both anesthetic groups (p>0.05). Low-flow anesthesia did not cause impairment in terms of renal and hepatic functions.