Effects of Carbon Dioxide Insufflation and Trendelenburg Position on Brain Oxygenation During Laparoscopy in Children

PURPOSE

Laparoscopic appendectomy has become more popular compared with the open appendectomy in children, but there are limited data on the effects of pneumoperitoneum and Trendelenburg position on cerebral oxygenation. This study was designed to evaluate the changes in cerebral saturation using near-infrared spectroscope during laparoscopic surgery in children.

METHODS

The children underwent laparoscopic (LAP Group, n=22) or open appendectomy (OPEN Group, n=22). Right and left cerebral oxygenation (RScO2-LScO2), heart rate (HR), mean arterial pressure (MAP), end-tidal CO2pressure (PETCO2), and peripheral oxygen saturations (SpO2) were recorded between anesthesia induction (T0, baseline), after induction (T1), after intubation (T2), 5 minutes after intubation (T3), 5 minutes after pneumoperitoneum-15th minute at OPEN (T4), 5 minutes after Trendelenburg-20th minute at OPEN (T5), 30 minutes after pneumoperitoneum-45th minute at OPEN (T6), 5 minutes after supine position-skin suturing at OPEN (T7), 5 minutes postextubation (T8).

RESULTS

Groups were similar with respect to their demographic data. In LAP group, a significant increase in HR was recorded at T5. No significant difference was observed in the MAP, PETCO2, SpO2, RScO2, and LScO2 values between the groups. There was a significant increase in the perioperative T1 to T8 values compared with the T0 values in LScO2 of the LAP group.

CONCLUSIONS

Our results suggest that pneumoperitoneum and Trendelenburg position does not alter the hemodynamic values and can be safely performed in children without altering regional brain oxygenation levels.

A cross-sectional study of the reporting quality of pilot or feasibility trials in high-impact anesthesia journals

PURPOSE

Pilot trials inform the design and conduct of larger scale trials. Using the Consolidated Standards of Reporting Trials (CONSORT) pilot extension guidelines, we assessed reporting quality in five high-impact anesthesia journals and explored factors associated with reporting quality.

METHODS

The five highest-impact anesthesia journals were screened for randomized-controlled trials published as pilot or feasibility trials between 2006 and 2016. A pair of reviewers independently screened citations, extracted data, and assessed reporting quality using the CONSORT pilot trial extension checklists for abstracts and full texts. We reported the percentage adherence for each item, along with the median [interquartile range (IQR)] or mean (standard deviation [SD]) for all items. The factors considered to influence reporting were: 1) trial registration, 2) industry funding, 3) trial identification as a pilot or feasibility in the title or abstract, 4) primary objective as "feasibility", and 5) the specific journal. The association was estimated using generalized estimating equations and reported as incidence rate ratios with 99% confidence intervals.

RESULTS

Of 364 citations, 58 articles were eligible. The median [IQR] number of CONSORT abstract items reported was 5 [4-7], and the mean (SD) number of full text items reported was 13 (5). Significantly poor reporting was associated with "not registering the trial" (both abstracts and full texts), "trial not identified as a pilot" (abstracts), and "using clinical hypothesis as the primary objective" (full texts).

CONCLUSION

The reporting quality of pilot trials published in leading anesthesia journals is poor. Journal editorial boards can encourage improved reporting by supporting adherence to the CONSORT extension for pilot trials.

Sevoflurane preserves regional cerebral oxygen saturation better than propofol: Randomized controlled trial

STUDY OBJECTIVE

To investigate possible effects of volatile induction and maintenance anesthesia with sevoflurane (VIMA) and total intravenous anesthesia with propofol (TIVA) on regional cerebral oxygen saturation (rcSo₂) during laparoscopic cholecystectomy.

DESIGN

Randomized, prospective and single-blinded study.

SETTING

Academic hospital.

PATIENTS

ASA physical status of I and II surgical patients, scheduled for elective laparoscopic cholecystectomy from March 2013 to October 2014.

MEASUREMENTS

Changes of regional cerebral oxygen saturation were measured by near-infrared spectroscopy on the left and right sides of forehead at different time points: before anesthesia induction (Tbas), immediately after induction (Tind), after applaying a pneumoperitoneum (TCo₂), 10 minutes after positioning the patient into reverse Trendelenburg's position (TrtCo₂), immediately after desufflation of gas (Tpost) and 30 (Trec30) and 60 (Trec60) minutes after emergence from anesthesia.

MAIN RESULTS

Study population included 124 patients, 62 in each group. There was no significant difference between these groups according to demographic characteristics, surgery and anesthesia times as well as in the basal rcSo₂ values. Statistically higher rSco₂ values were noted in the VIMA group when compared to the TIVA group in all time points Tind, TCo₂, TrtCo₂, Tpost, Trec30 and Trec60 and incidence of critical rcSo₂ decreases was statistically lower in VIMA group (P<.05). There were no serious perioperative complications.

CONCLUSIONS

VIMA technique provides significantly (4%-11%) higher rcSO₂ values during general anesthesia for laparoscopic cholecystectomy, when compared with TIVA and also provides significantly less number of critical rcSO₂ decreases.

A comparative analysis of the effects of sevoflurane and propofol on cerebral oxygenation during steep Trendelenburg position and pneumoperitoneum for robotic-assisted laparoscopic prostatectomy

Purpose

Steep Trendelenburg position and pneumoperitoneum during robotic-assisted laparoscopic prostatectomy (RALP) increase intracranial pressure (ICP) and may alter cerebral blood flow (CBF) and oxygenation. Volatile anesthetics and propofol have different effects on ICP, CBF, and cerebral metabolic rate and may have different impact on cerebral oxygenation during RALP. In this study, we measured jugular venous bulb oxygenation (SjO₂) and regional oxygen saturation (SctO₂) in patients undergoing RALP to evaluate cerebral oxygenation and compared the effects of sevoflurane and propofol. We also verified whether SctO₂ may be an alternative to SjO₂.

Methods

Fifty patients scheduled for RALP were randomly assigned to undergo sevoflurane (group S) or propofol (group P) anesthesia. SjO₂, SctO₂, mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), central venous pressure (CVP), partial pressures of arterial oxygen (PaO₂) and carbon dioxide (PaCO₂), hemoglobin concentration (Hb), Bispectral Index (BIS) and nasopharyngeal temperature (BT) were recorded 5 min before surgery commencement, 5 min after pneumoperitoneum, 5, 30, 60, 90, and 120 min after pneumoperitoneum in a Trendelenburg position, and after desufflation in a supine position.

Results

SjO₂ was significantly higher in group S than in group P at all measurement points [group S vs. group P: 77 % (11) vs. 65 % (13), mean of all measurement points (1SD); p < 0.01]. Linear regression analysis (β = 0.106; r² = 0.065; p = 0.004) shows a weak relationship between SjO₂ and SctO₂.

Conclusions

Sevoflurane maintains higher SjO₂ levels than propofol during RALP. SctO₂ does not accurately reflect SjO₂.

Resting-state Functional Magnetic Resonance Imaging Correlates of Sevoflurane-induced Unconsciousness

BACKGROUND

Blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) has been used to study the effects of anesthetic agents on correlated intrinsic neural activity. Previous studies have focused primarily on intravenous agents. The authors studied the effects of sevoflurane, an inhaled anesthetic.

METHODS

Resting-state BOLD fMRI was acquired from 10 subjects before sedation and from 9 subjects rendered unresponsive by 1.2% sevoflurane. The fMRI data were analyzed taking particular care to minimize the impact of artifact generated by head motion.

RESULTS

BOLD correlations were specifically weaker within the default mode network and ventral attention network during sevoflurane-induced unconsciousness, especially between anterior and posterior midline regions. Reduced functional connectivity between these same networks and the thalamus was also spatially localized to the midline frontal regions. The amplitude of BOLD signal fluctuations was substantially reduced across all brain regions. The importance of censoring epochs contaminated by head motion was demonstrated by comparative analyses.

CONCLUSIONS

Sevoflurane-induced unconsciousness is associated with both globally reduced BOLD signal amplitudes and selectively reduced functional connectivity within cortical networks associated with consciousness (default mode network) and orienting to salient external stimuli (ventral attention network). Scrupulous attention to minimizing the impact of head motion artifact is critical in fMRI studies using anesthetic agents.