Accessory and Expiratory Muscles Activation During Spontaneous Breathing Trial: A Physiological Study by Surface Electromyography.

Background: The physiological and prognostical significance of accessory and expiratory muscles activation is unknown during a spontaneous breathing trial (SBT). We hypothesized that, in patients experiencing weaning failure, accessory and expiratory muscles are activated to cope with an increased respiratory workload. Purpose: To describe accessory and expiratory muscle activation non-invasively by surface electromyography (sEMG) during an SBT and to assess differences in electrical activity (EA) of the inspiratory and expiratory muscles in successful vs. failing weaning patients. Methods: Intubated patients on mechanical ventilation for more than 48 h undergoing an SBT were enrolled in a medical and surgical third-level ICU of the University Teaching Hospital. Baseline characteristics and physiological variables were recorded in a crossover physiologic prospective clinical study. Results: Of 37 critically ill mechanically ventilated patients, 29 (78%) patients successfully passed the SBT. Rapid shallow breathing index (RSBI) was higher in patients who failed SBT compared with the successfully weaned patients at baseline and over time (group-by-time interaction p < 0.001). EA of both the diaphragm (EAdisurf) and of accessory muscles (ACCsurf) was higher in failure patients compared with success (group-by-time interaction p = 0.0174 and p < 0.001, respectively). EA of expiratory muscles (ESPsurf) during SBT increased more in failure than in weaned patients (group-by-time interaction p < 0.0001). Conclusion: Non-invasive respiratory muscle monitoring by sEMG was feasible during SBT. Respiratory muscles EA increased during SBT, regardless of SBT outcome, and patients who failed the SBT had a higher increase of all the inspiratory muscles EA compared with the patients who passed the SBT. Recruitment of expiratory muscles-as quantified by sEMG-is associated with SBT failure.

Bedside Selection of Positive End Expiratory Pressure by Electrical Impedance Tomography in Patients Undergoing Veno-Venous Extracorporeal Membrane Oxygenation Support: A Comparison between COVID-19 ARDS and ARDS from Other Etiologies.

BACKGROUND: The interest in protective ventilation strategies and individualized approaches for patients with severe illness on veno venous extracorporeal support has increased in recent years. Wide heterogeneity exists among patients with COVID-19 related acute respiratory distress syndrome (C-ARDS) and ARDS from other etiologies (NC-ARDS). EIT is a useful tool for the accurate analysis of regional lung volume distribution and allows for a tailored ventilatory setting. The aim of this work is to retrospectively describe the results of EIT assessments performed in patients C-ARDS and NC-ARDS undergoing V-V ECMO support. METHODS: A clinical EIT-guided decremental PEEP trail was conducted for all patients included in the study and mechanically ventilated. RESULTS: 12 patients with C-ARDS and 12 patients with NC-ARDS were included in the study for a total of 13 and 18 EIT evaluations, respectively. No significant differences in arterial blood gas, respiratory parameters, and regional ventilation before and after the EIT exam were recorded. The subset of patients with NC-ARDS whose EIT exam led to PEEP modification was characterized by a lower baseline compliance compared with the C-ARDS group: 18 (16-28) vs. 27 (24-30) (p = 0.04). Overdistension significantly increased at higher steps only for the NC-ARDS group. A higher percentage of overdistension was described in patients with NC-ARDS when compared with patients with C-ARDS. CONCLUSIONS: EIT is feasible in patients with COVID-19-associated ARDS on veno-venous extracorporeal support and may help in tailoring the PEEP setting. Overall, severe COVID-19-related ARDS presents respiratory characteristics similar to severe "classical" NC-ARDS. However, C-ARDS is associated with a lower risk of overdistension at a higher PEEP level compared with NC-ARDS.

Bag valve resuscitator versus Mapleson C circuit during manual ventilation: A bench top study.

BACKGROUND: Manual ventilation is life saving in critically ill patients. The lack of airway pressure monitoring makes it operator and device dependent. In this bench top-study, we compared a self- inflating bag valve resuscitator and a Mapleson C circuit during manual ventilation performed by critical care nurses under normal and pathologic conditions, with a special focus on delivered positive end expiratory pressure (PEEP). METHODS: Three different respiratory patterns (normal, restrictive and obstructive) were reproduced by a breathing simulator. Twenty nurses provided manual ventilation with a specific ventilatory pattern. Airway pressure, tidal volume and respiratory rate were recorded. Absolute value, error (difference between recorded and target values) and variability of PEEP were analysed. RESULTS: 3820 breathing traces were analysed. PEEP error was significantly higher with Mapelson C (43.3% vs 5.9% respectively, p < 0.001). This finding was confirmed regardless of operator skill and scenario. PEEP was more variable with Mapelson C (p < 0.05 in all scenarios). Ventilation of obstructive patients with Mapelson C resulted in higher PEEP levels compared to the reference value. Conversely, in the restrictive setting, PEEP was lower. Difference between PEEP and the minimum pressure recorded during the respiratory cycle was significantly higher with Mapelson C (p < 0.05). CONCLUSIONS: Manual ventilation with a Mapleson C circuit delivered a less accurate and less stable PEEP level compared to a self-inflating bag valve resuscitator.

Clinical value of electrical impedance tomography (EIT) in the management of patients with acute respiratory failure: a single centre experience.

Objective.We will describe our clinical experience using electrical impedance tomography (EIT) in the management of mechanical ventilation in patients with acute respiratory failure and to determine to which extent EIT-guided positive end-expiratory pressure (PEEP) setting differed from clinically set values.Approach.We conducted a retrospective, observational cohort study performed in a hub centre for the treatment of acute respiratory failure and veno-venous extracorporeal membrane oxygenation (ECMO).Main results.Between January 2017 and December 2019, EIT was performed 54 times in 41 patients, not feasible only in one case because of signal instability. More than 50% was on veno-venous ECMO support. In 16 cases (30%), EIT was used for monitoring mechanical ventilation, i.e. to evaluate recruitability or sigh setting. In 37 cases (70%), EIT was used to set PEEP both with incremental (11 cases in nine patients) and decremental (26 cases, 18 patients) PEEP trial. Clinical PEEP before the decremental PEEP trial (PEEPPRE) was 14.1 ± 3.4 cmH2O and clinical PEEP set by clinicians after the PEEP trial (PEEPPOST) was 13.6 ± 3.1 (p = ns). EIT analyses demonstrated that more hypoxic patients were higher derecruited when compared to less hypoxic patients that were, on the contrary, more overdistended (p < 0.05). No acute effects of PEEP adjustment based on EIT on respiratory mechanics or regional EIT parameters modification were observed.Significance.The variability of EIT findings in our population confirmed the need to provide ventilation settings individually tailored and EIT was confirmed to be an optimal useful clinical bedside noninvasive tool to provide real-time monitoring of the PEEP effect and ventilation distribution.

Modified pediatric lung ultrasound score compared with computed tomography for assessment of lung aeration in children.

BACKGROUND: Lung ultrasound can be used to assess lung density and aeration at the bedside. Few authors have investigated scores based on the ultrasonographic interstitial syndrome for this purpose, but none have compared them with the gold standard computed tomography in children. METHODS: Children <10 kilograms undergoing a chest computed tomography for clinical purposes at a tertiary hospital Pediatric Intensive Care Unit were enrolled in the study. An ultrasound scan was performed shortly after computed tomography. Each hemithorax was divided in six zones, and each zone was scored: 1, no B lines; 2, <3 B lines; 3, >3 well separated B lines; 4, crowded, coalescent B lines; 5, white lung; 6, consolidation. The pediatric lung ultrasound score was obtained by adding all zones. Interobserver variation for two separate operators was calculated. RESULTS: Ten children, median age 95 days (range 23-721) were enrolled. Mean pediatric lung ultrasound score had a significant correlation with lung density (r=0.68) and percentage of hypoaerated lung (r=0.51). Median density and percentage of hypoaerated lung increased along the ultrasound patterns values (P<0.05) although not all patterns were significantly different from adjacent ones in the pairwise comparison. Interobserver variability in scoring of ultrasonographic patterns was moderate. CONCLUSIONS: The pediatric lung ultrasound score correlates with lung density and percentage of hypoaerated lung measured with computed tomography.

Dynamic bedside assessment of the physiologic effects of prone position in acute respiratory distress syndrome patients by electrical impedance tomography.

BACKGROUND: Prone position (PP) improves acute respiratory distress syndrome (ARDS) survival by reducing the risk of ventilation-induced lung injury. However, inter-individual variability is a hallmark of ARDS and lung protection by PP might not be optimal in all patients. In the present study, we dynamically assessed physiologic effects of PP by electrical impedance tomography (EIT) and identified predictors of improved lung protection by PP in ARDS patients. METHODS: Prospective physiologic study on 16 intubated, sedated and paralyzed patients with ARDS undergoing PP as per clinical decision. EIT data were recorded during two consecutive steps: 1) baseline supine position before and after a recruitment maneuver (RM); 2) prone position before and after a RM. "Improved lung protection" by PP was defined in the presence of simultaneous improvement of ventilation homogeneity (Hom), alveolar overdistension and collapse (ODCL) and amount of recruitable lung volume by RM in comparison to supine. RESULTS: PP versus supine increased the tidal volume distending the dependent regions (Vtdep), resulting in improved Hom (1.1±0.9 vs. 1.7±0.9, P=0.021). PP also reduced ODCL (19±9% vs. 28±8%, P=0.005) and increased the recruitable lung volume (80 [71-157] vs. 59 [1-110] mL, P=0.025). "Improved lung protection" by PP was predicted by lower Vtdep, higher Vtndep and poorer Hom measured during baseline supine position (P<0.05). CONCLUSIONS: EIT enables dynamic bedside assessment of the physiologic effects of PP and might support early recognition of ARDS patients more likely to benefit from PP.

Occurrence of pendelluft under pressure support ventilation in patients who failed a spontaneous breathing trial: an observational study.

BACKGROUND: Pendelluft, the movement of gas within different lung regions, is present in animal models of assisted mechanical ventilation and associated with lung overstretching. Due to rebreathing of CO2 as compared to fresh gas, pendelluft might reduce ventilatory efficiency possibly exacerbating patient's respiratory workload during weaning. Our aim was to measure pendelluft by electrical impedance tomography (EIT) in patients who failed a spontaneous breathing trial (SBT). METHODS: This is an observational study conducted in a general intensive care unit of a tertiary-level teaching hospital. EIT signal was recorded in 20 patients while pressure support (PS) ventilation was progressively reduced from clinical level (baseline) to 2 cmH2O, as in an SBT; four ventral-to-dorsal lung regions of interest were identified for pendelluft measurement. A regional gas movement (> 6 mL) occurring in a direction opposite to the global EIT signal was considered diagnostic for high pendelluft. RESULTS: Eight patients out of 20 (40%) were classified as high-pendelluft; baseline clinical characteristics did not differ between high- and low-pendelluft patients. At PS reduction, pendelluft and EtCO2 increased more in the high-pendelluft group (p < .001 and .011, respectively). The volume of gas subject to pendelluft moved almost completely from the ventral towards the dorsal lung regions, while the opposite movement was minimal (16.3 [10:32.8] vs. 0 [0:1.8] mL, p = .001). In a subgroup of patients, increased pendelluft volumes positively correlated with markers of respiratory distress such as increased respiratory rate, p0.1, and EtCO2. CONCLUSIONS: Occult pendelluft can be measured by EIT, and is frequently present in patients failing an SBT. When present, pendelluft increases with the reduction of ventilator support and is associated with increased EtCO2, suggesting a reduction of the ability to eliminate CO2.

Pressure support ventilation, sigh adjunct to pressure support ventilation, and neurally adjusted ventilatory assist in infants after cardiac surgery: A physiologic crossover randomized study.

OBJECTIVES: We sought to compare gas exchange, respiratory mechanics, and asynchronies during pressure support ventilation (PSV), sigh adjunct to PSV (PSV SIGH), and neurally adjusted ventilatory assist (NAVA) in hypoxemic infants after cardiac surgery. DESIGN: Prospective, single-center, crossover, randomized physiologic study. SETTING: Tertiary-care pediatric intensive care unit. PATIENTS: Fourteen hypoxemic infants (median age 11.5 days [8.7-74]). INTERVENTIONS: The protocol begins with a 1 hour step of PSV, followed by two consecutive steps in PSV SIGH and NAVA in random order, with a washout period of 30 minutes (PSV) between them. MAIN RESULTS: Three infants presented an irregular Eadi signal because of diaphragmatic paralysis and were excluded from analysis. For the remaining 11 infants, PaO2 /FiO 2 and oxygenation index improved in PSV SIGH compared with PSV (P < 0.05) but not in NAVA compared with PSV. PSV SIGH showed increased tidal volumes and lower respiratory rate than PSV (P < 0.05), as well as a significant improvement in compliance with respiratory system indexed to body weight when compared with both PSV and NAVA (P < 0.01). No changes in mean airway pressure was registered among steps. Inspiratory time resulted prolonged for both PSV SIGH and NAVA than PSV (P < 0.05). NAVA showed the higher coefficient of variability in respiratory parameters and a significative decrease in asynchrony index when compared with both PSV and PSV SIGH (P < 0.01). CONCLUSIONS: The adjunct of one SIGH per minute to PSV improved oxygenation and lung mechanics while NAVA provided the best patient-ventilator synchrony in infants after cardiac surgery.

Measurement of Diaphragmatic Electrical Activity by Surface Electromyography in Intubated Subjects and Its Relationship With Inspiratory Effort.

BACKGROUND: Quantification of patient effort during spontaneous breathing is important to tailor ventilatory assistance. Because a correlation between inspiratory muscle pressure (Pmus) and electrical activity of the diaphragm (EAdi) has been described, we aimed to assess the reliability of surface electromyography (EMG) of the respiratory muscles for monitoring diaphragm electrical activity and subject effort during assisted ventilation. METHODS: At a general ICU of a single university-affiliated hospital, we enrolled subjects who were intubated and on pressure support ventilation (PSV) and were on mechanical ventilation for > 48 h. The subjects were studied at 3 levels of pressure support. Airway flow and pressure; esophageal pressure; EAdi; and surface EMG of the diaphragm (surface EAdi), intercostal, and sternocleidomastoid muscles were recorded. Respiratory cycles were sampled for off-line analysis. The Pmus/EAdi index (PEI) was calculated by relying on EAdi and surface EAdi (surface PEI) from an airway pressure drop during end-expiratory occlusions performed every minute. RESULTS: surface EAdi well correlated with EAdi and Pmus, in particular, after averaging breaths into deciles (R = 0.92 and R = 0.84). When surface PEI was used with surface EAdi, it provided a reliable estimation of Pmus (R = 0.94 in comparison with measured Pmus). CONCLUSIONS: During assisted mechanical ventilation, EAdi can be reliably monitored by both EAdi and surface EMG. The measurement of Pmus based on the calibration of EAdi was also feasible by the use of surface EMG.

Bedside selection of positive end-expiratory pressure by electrical impedance tomography in hypoxemic patients: a feasibility study.

BACKGROUND: Positive end-expiratory pressure (PEEP) is a key element of mechanical ventilation. It should optimize recruitment, without causing excessive overdistension, but controversy exists on the best method to set it. The purpose of the study was to test the feasibility of setting PEEP with electrical impedance tomography in order to prevent lung de-recruitment following a recruitment maneuver. We enrolled 16 patients undergoing mechanical ventilation with PaO2/FiO2 <300 mmHg. In all patients, under constant tidal volume (6-8 ml/kg) PEEP was set based on the PEEP/FiO2 table proposed by the ARDS network (PEEPARDSnet). We performed a recruitment maneuver and monitored the end-expiratory lung impedance (EELI) over 10 min. If the EELI signal decreased during this period, the recruitment maneuver was repeated and PEEP increased by 2 cmH2O. This procedure was repeated until the EELI maintained a stability over time (PEEPEIT). RESULTS: The procedure was feasible in 87% patients. PEEPEIT was higher than PEEPARDSnet (13 ± 3 vs. 9 ± 2 cmH2O, p < 0.001). PaO2/FiO2 improved during PEEPEIT and driving pressure decreased. Recruited volume correlated with the decrease in driving pressure but not with oxygenation improvement. Finally, regional alveolar hyperdistention and collapse was reduced in dependent lung layers and increased in non-dependent lung layers. CONCLUSIONS: In hypoxemic patients, a PEEP selection strategy aimed at stabilizing alveolar recruitment guided by EIT at the bedside was feasible and safe. This strategy led, in comparison with the ARDSnet table, to higher PEEP, improved oxygenation and reduced driving pressure, allowing to estimate the relative weight of overdistension and recruitment.

The Ratio of Inspiratory Pressure Over Electrical Activity of the Diaphragm Remains Stable During ICU Stay and is not Related to Clinical Outcome.

BACKGROUND: We previously described an index, defined as the ratio between the inspiratory muscle pressure (Pmus) and the electrical activity of the diaphragm (EA(di)) (Pmus/EA(di) index). In the present work, we describe the trend of Pmus/EA(di) index over time, investigating whether it could be an indicator of muscular efficiency associated with risk factors for diaphragmatic injury and/or clinical outcomes. METHODS: This work is a retrospective analysis of subjects with measurements of Pmus/EA(di) index obtained, on different days, during assisted ventilation. Effects of Pmus/EA(di) index absolute value on clinical outcomes were investigated dividing subjects into those with Pmus/EA(di) index higher or lower than the median. Effects of Pmus/EA(di) index trend over time were analyzed, distinguishing between subjects with Pmus/EA(di) index increasing or decreasing. RESULTS: Mean Pmus/EA(di) index was 1.04 ± 0.67, and the median (interquartile range) was 1.00 (0.59-1.34), without a systematic trend over the days. Demographic, ventilator, or outcome data did not significantly differ between subjects with Pmus/EA(di) index higher or lower than the median. Similarly, we did not find relevant differences in subjects with Pmus/EA(di) index increasing or decreasing over time. CONCLUSIONS: The Pmus/EA(di) index value remained constant in each subject over time, although the inter-individual variability was high. Neither the Pmus/EA(di) index nor its trends appeared to be associated with ventilatory variables or clinical outcome.

The use of a novel cleaning closed suction system reduces the volume of secretions within the endotracheal tube as assessed by micro-computed tomography: a randomized clinical trial.

BACKGROUND: Early after intubation, a layer of biofilm covers the inner lumen of the endotracheal tube (ETT). Cleaning the ETT might prevent airways colonization by pathogens, reduce resistance to airflow, and decrease sudden ETT obstruction. We investigated the effectiveness of a cleaning closed suction system in maintaining the endotracheal tube free from secretions. METHODS: We conducted a single center, randomized controlled trial, in the general intensive care unit of a tertiary-level university hospital. We enrolled 40 adult critically ill patients expected to remain intubated for more than 48 h, within 24 h from intubation. Patients were randomized to receive three ETT cleaning maneuvers/day using a novel device (Airway Medix Closed Suction System™, cleaning group) or to standard care (no ETT cleaning, standard closed suction, control group). After extubation, the amount of secretions in the ETTs was measured by micro-computed tomography. RESULTS: The volume of secretions in the ETTs from the cleaning group was lower than controls (0.081 [0.021-0.306] vs. 0.568 [0.162-0.756] mL, p = 0.001), corresponding to a cross-sectional area reduction six times lower (1[0-3] vs. 6 [2-10] %, p = 0.001). In a subset of 16 patients, the resistance to airflow tended to be lower after 1 day of treatment (p = 0.063) and was lower after 2 days (0.024), while no difference was present at enrollment (p = 0.922). ETT colonization did not differ between the two groups. CONCLUSIONS: The use of a novel cleaning closed suction system proved to be effective in reducing secretions present in the ETT after extubation, possibly reducing resistance to airflow during intubation. TRIAL REGISTRATION: clinicaltrials.gov NCT01912105.

External Ventricular and Lumbar Drain Device Infections in ICU Patients: A Prospective Multicenter Italian Study.

OBJECTIVE: Use of external ventricular drains and lumbar catheters is associated with a risk of ventriculitis and meningitis ranging from 2% to 24% because of lack of standardized diagnostic criteria. We evaluated the prevalence of ventriculitis or meningitis in 13 Italian ICUs. DESIGN: Multicenter, prospective study. SETTING: Thirteen Italian ICUs. PATIENTS: Two hundred seventy-one patients (mean age, 57 yr) receiving a total number of 311 catheters. Two hundred fifty patients (92.2%) had an external ventricular drain, 17 patients (6.3%) had a lumbar catheter, and four patients (1.5%) had both external ventricular drain and lumbar catheter. INTERVENTIONS: ICUs enrolled at least 10 consecutive adult patients with an external ventricular drain or lumbar catheter in place for more than 24 hours. Confirmed cerebrospinal fluid infection was defined by presence of a positive cerebrospinal fluid culture, a cerebrospinal fluid/blood glucose ratio less than 0.5, a neutrophilic cerebrospinal fluid pleocytosis (> 5 cells/µL), and fever. Abnormal cerebrospinal fluid findings with negative cultures were defined as suspected infection. MEASUREMENTS AND MAIN RESULTS: Median duration of device use was 13 days (interquartile range, 8-19). Fifteen patients (5.5%) had a confirmed ventriculitis or meningitis, and 15 patients (5.5%) had a suspected ventriculitis or meningitis. Cerebrospinal fluid glucose and cerebrospinal fluid/blood glucose ratio were lower in patients with confirmed ventriculitis or meningitis and suspected ventriculitis or meningitis; proteins and lactates were significantly higher in confirmed ventriculitis or meningitis. Gram-negative and Gram-positive bacteria were equally cultured. Risk factors for infection were a concomitant extracranial infection (odds ratio, 2.34; 95% CI, 1.01-5.40; p = 0.05) and placement of catheters outside the operation room (odds ratio, 4.01; 95% CI, 0.98-16.50; p = 0.05). CONCLUSIONS: Ventriculitis or meningitis remains a problem in Italian ICUs, and a strategy for reducing the prevalence is worth planning.

Variability in brain death determination in europe: looking for a solution.

BACKGROUND: Criteria for determining brain death (BD) vary between countries. We report the results of an investigation designed to compare procedures to determine BD in different European countries. METHODS: We developed a web-based questionnaire that was sent to representatives of 33 European countries. Responses were reviewed, and individual respondents were contacted if clarification was required. RESULTS: Responses were received from 28 (85 %) of the 33 countries to which the questionnaire was sent. Each country has either a law (93 %) or national guidance (89 %) for defining BD. Clinical examination is sufficient to determine BD in 50 % of countries; coma, apnea, absence of corneal, and cough reflexes are mandatory criteria in all. Confirmation of apnea is required in all countries but not defined in 4 (14 %). In the 24 (86 %) of countries with a formal definition of the apnea test, a target pCO2 level (23/24, 96 %) is the pre-specified end point in most. The (median, range) number of clinical examinations (2, 1-3) and minimum observation time between tests (3 h, 0-12 h) vary greatly between countries. Additional (confirmatory) tests are required in 50 % of countries. Hypothermia (4 %), anoxic injury (7 %), inability to complete clinical examination (61 %), toxic drug levels (57 %), and inconclusive apnea test (54 %) are among the most common indications for confirmatory tests. Cerebral blood flow (CBF) investigation is mandatory in 18 % of countries, but optional or indicated only in selected cases in 82 %. Conventional angiography is the preferred method of determining absent CBF (50 %), followed by transcranial Doppler sonography (43 %), computerized tomography (CT) angiography (39 %), CT perfusion, and magnetic resonance imaging (MRI) angiography (11 %). Electroencephalography is always (21 %) or optionally (14 %) recorded. CONCLUSIONS: Although legislation or professional guidance is available to standardize nationally the BD diagnosis process in all European countries, there are still disparities between countries. The current variation in practice makes an international consensus for the definition of BD imperative.

Measurement of endotracheal tube secretions volume by micro computed tomography (MicroCT) scan: an experimental and clinical study.

BACKGROUND: Biofilm accumulates within the endotracheal tube (ETT) early after intubation. Contaminated secretions in the ETT are associated with increased risk for microbial dissemination in the distal airways and increased resistance to airflow. We evaluated the effectiveness of micro computed tomography (MicroCT) for the quantification of ETT inner volume reduction in critically ill patients. METHODS: We injected a known amount of gel into unused ETT to simulate secretions. We calculated the volume of gel analyzing MicroCT scans for a length of 20 cm. We then collected eleven ETTs after extubation of critically ill patients, recording clinical and demographical data. We assessed the amount of secretions by MicroCT and obtained ETT microbiological cultures. RESULTS: Gel volumes assessed by MicroCT strongly correlated with injected gel volumes (p < 0.001, r2 = 0.999).MicroCT revealed the accumulation of secretions on all the ETTs (median 0.154, IQR:0.02-0.837 mL), corresponding to an average cross-sectional area reduction of 1.7%. The amount of secretions inversely correlated with patients' age (p = 0.011, rho = -0.727) but not with days of intubation, SAPS2, PaO2/FiO2 assessed on admission. Accumulation of secretions was higher in the cuff region (p = 0.003). Microbial growth occurred in cultures from 9/11 ETTs, and did not correlate with secretions amount. In 7/11 cases the same microbes were identified also in tracheal aspirates. CONCLUSIONS: MicroCT appears as a feasible and precise technique to measure volume of secretions within ETTs after extubation. In patients, secretions tend to accumulate in the cuff region, with high variability among patients.

Incidence of pain after craniotomy in children.

BACKGROUND: There is very few information regarding pain after craniotomy in children. OBJECTIVES: This multicentre observational study assessed the incidence of pain after major craniotomy in children. METHODS: After IRB approval, 213 infants and children who were <10 years old and undergoing major craniotomy were consecutively enrolled in nine Italian hospitals. Pain intensity, analgesic therapy, and adverse effects were evaluated on the first 2 days after surgery. Moderate to severe pain was defined as a median FLACC or NRS score ≥ 4 points. Severe pain was defined as a median FLACC or NRS score ≥ 7 points. RESULTS: Data of 206 children were included in the analysis. The overall postoperative median FLACC/NRS scores were 1 (IQR 0 to 2). Twenty-one children (16%) presented moderate to severe pain in the recovery room and 14 (6%) during the first and second day after surgery. Twenty-six children (19%) had severe pain in the recovery room and 4 (2%) during the first and second day after surgery. Rectal codeine was the most common weak opiod used. Remifentanil and morphine were the strong opioids widely used in PICU and in general wards, respectively. Longer procedures were associated with moderate to severe pain (OR 1.30; CI 1.07-1.57) or severe pain (OR 1.41; 1.09-1.84; P < 0.05). There were no significant associations between complications, pain intensity, and analgesic therapy. CONCLUSION: Children receiving multimodal analgesia experience little or no pain after major craniotomy. Longer surgical procedures correlate with an increased risk of having postoperative pain.

Xenon anaesthesia produces better early postoperative cognitive recovery than sevoflurane anaesthesia.

BACKGROUND AND OBJECTIVE: Xenon anaesthesia may have the potential to reduce postoperative cognitive impairment after general anaesthesia. This randomized double-blind controlled trial was designed to compare the early postoperative cognitive recovery after xenon and sevoflurane anaesthesia. METHODS: After institutional ethics approval, we obtained informed written consent from 60 adults, with American Society of Anesthesiologists I or II status, scheduled for elective surgery with an estimated surgery time between 60 and 360 min. Patients were randomized to receive xenon or sevoflurane anaesthesia. Both groups received a remifentanil infusion adjusted to clinical needs based on patients' haemodynamic and state entropy of less than 60. In cases of state entropy of at least 60 during the first 15 min after induction, patients in the xenon group received a propofol infusion targeted to state entropy of less than 60. The primary end-point of the study was the early postoperative cognitive recovery evaluated by the Short Orientation Memory Concentration Test. RESULTS: There was no significant difference in the mean preoperative Short Orientation Memory Concentration Test values between groups (sevoflurane 2.7 +/- 3.2 and xenon 3.2 +/- 2.6; P, 0.53). Awakening was significantly faster in the xenon group (sevoflurane 8 +/- 4 min and xenon 3 +/- 1 min; P < 0.001). Patients receiving xenon presented significantly lower Short Orientation Memory Concentration Test scores at 30 min (sevoflurane 6.7 +/- 5.9 and xenon 3.3 +/- 3.1; P 0.003) and 60 min (xenon 2.1 +/- 3 and sevoflurane 5 +/- 4.1; P 0.003) after extubation. CONCLUSION: Xenon anaesthesia was associated with faster emergence and with better early postoperative cognitive recovery than sevoflurane anaesthesia.