Development and validation of the Ex-Care BR model: a multicentre initiative for identifying Brazilian surgical patients at risk of 30-day in-hospital mortality.

BACKGROUND: Surgical risk stratification is crucial for enhancing perioperative assistance and allocating resources efficiently. However, existing models may not capture the complexity of surgical care in Brazil. Using data from various healthcare settings nationwide, we developed a new risk model for 30-day in-hospital mortality (the Ex-Care BR model). METHODS: A retrospective cohort study was conducted in 10 hospitals from different geographic regions in Brazil. Data were analysed using multilevel logistic regression models. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC), Brier score, and calibration plots. Derivation and validation cohorts were randomly assigned. RESULTS: A total of 107,372 patients were included, and 30-day in-hospital mortality was 2.1% (n=2261). The final risk model comprised four predictors related to the patient and surgery (age, ASA physical status classification, surgical urgency, and surgical size), and the random effect related to hospitals. The model showed excellent discrimination (AUROC=0.93, 95% confidence interval [CI], 0.93-0.94), calibration, and overall performance (Brier score=0.017) in the derivation cohort (n=75,094). Similar results were observed in the validation cohort (n=32,278) (AUROC=0.93, 95% CI, 0.92-0.93). CONCLUSIONS: The Ex-Care BR is the first model to consider regional and organisational peculiarities of the Brazilian surgical scene, in addition to patient and surgical factors. It is particularly useful for identifying high-risk surgical patients in situations demanding efficient allocation of limited resources. However, a thorough exploration of mortality variations among hospitals is essential for a comprehensive understanding of risk. CLINICAL TRIAL REGISTRATION: NCT05796024.

Global anaesthesia-related cardiac arrest rates in children: a systematic review and meta-analysis.

BACKGROUND: Neonates and infants have a higher perioperative risk of cardiac arrest and mortality than adults. The Human Development Index (HDI) ranges from 0 to 1, representing the lowest and highest levels of development, respectively. The relation between anaesthesia safety and country HDI has been described previously. We examined the relationship among the anaesthesia-related cardiac arrest rate (ARCAR), country HDI, and time in a mixed paediatric patient population. METHODS: Electronic databases were searched up to July 2022 for studies reporting 24-h postoperative ARCARs in children. ARCARs (per 10,000 anaesthetic procedures) were analysed in low-HDI (HDI<0.8) vs high-HDI countries (HDI≥0.8) and over time (pre-2001 vs 2001-22). The magnitude of these associations was studied using systematic review methods with meta-regression analysis and meta-analysis. RESULTS: We included 38 studies with 5,493,489 anaesthetic procedures and 1001 anaesthesia-related cardiac arrests. ARCARs were inversely correlated with country HDI (P<0.0001) but were not correlated with time (P=0.82). ARCARs did not change between the periods in either high-HDI or low-HDI countries (P=0.71 and P=0.62, respectively), but were higher in low-HDI countries than in high-HDI countries (9.6 vs 2.0; P<0.0001) in 2001-22. ARCARs were higher in children aged <1 yr than in those ≥1 yr in high-HDI (10.69 vs 1.48; odds ratio [OR] 8.03, 95% confidence interval [CI] 5.96-10.81; P<0.0001) and low-HDI countries (36.02 vs 2.86; OR 7.32, 95% CI 3.48-15.39; P<0.0001) in 2001-22. CONCLUSIONS: The high and alarming anaesthesia-related cardiac arrest rates among children younger than 1 yr of age in high-HDI and low-HDI countries, respectively, reflect an ongoing challenge for anaesthesiologists. SYSTEMATIC REVIEW PROTOCOL: PROSPERO CRD42021229919.

High concentrations of waste anesthetic gases induce genetic damage and inflammation in physicians exposed for three years: A cross-sectional study.

This cross-sectional study analyzed the impact of occupational waste anesthetic gases on genetic material, oxidative stress, and inflammation status in young physicians exposed to inhalational anesthetics at the end of their medical residency. Concentrations of waste anesthetic gases were measured in the operating rooms to assess anesthetic pollution. The exposed group comprised individuals occupationally exposed to inhalational anesthetics, while the control group comprised individuals without anesthetic exposure. We quantified DNA damage; genetic instability (micronucleus-MN); protein, lipid, and DNA oxidation; antioxidant activities; and proinflammatory cytokine levels. Trace concentrations of anesthetics (isoflurane: 5.3 ± 2.5 ppm, sevoflurane: 9.7 ± 5.9 ppm, and nitrous oxide: 180 ± 150 ppm) were above international recommended thresholds. Basal DNA damage and IL-17A were significantly higher in the exposed group [27 ± 20 a.u. and 20.7(19.1;31.8) pg/mL, respectively] compared to the control group [17 ± 11 a.u. and 19.0(18.9;19.5) pg/mL, respectively], and MN frequency was slightly increased in the exposed physicians (2.3-fold). No significant difference was observed regarding oxidative stress biomarkers. The findings highlight the genetic and inflammatory risks in young physicians exposed to inhalational agents in operating rooms lacking adequate scavenging systems. This potential health hazard can accompany these subjects throughout their professional lives and reinforces the need to reduce ambient air pollution and consequently, occupational exposure.

Expression and promoter methylation status of two DNA repair genes in leukocytes from patients undergoing propofol or isoflurane anaesthesia.

Despite the widespread use of the anaesthetics propofol (PROP) and isoflurane (ISO), data about their toxicogenomic potential and interference in epigenetic events are unknown. This study evaluated the expression and methylation profile of two important DNA-repair genes (XRCC1 and hOGG1) in 40 patients undergoing elective and minimally invasive surgery (tympanoplasty and septoplasty) under ISO or PROP anaesthesia. The endpoints were examined at three sampling times: before anaesthesia (T0), 2 h after the beginning of anaesthesia (T2) and 24 h after the beginning of surgery (T24). Both gene expressions were assessed by quantitative real-time polymerase chain reaction (qRT-PCR), whereas methylation specific-PCR (MS-PCR) evaluated the DNA methylation patterns. Increased expression of XRCC1 was observed at T2 only in the PROP group. On the other hand, hOGG1 and XRCC1 expressions were decreased at T24 in both groups. There were no statistical significant differences between the two anaesthetics at the respective sampling times. The methylation status of XRCC1 (methylated at T0) and hOGG1 (unmethylated at T0) remained unchanged in the three sampling times. In conclusion, this study showed modulations of hOGG1 and XRCC1 expression especially 1 day after elective surgery in patients undergoing PROP and ISO anaesthesia. However, the data indicated that methylation was not the mechanism by which the genes were regulated. More studies are warranted to further investigate the possible epigenetic mechanisms involved after exposure to anaesthetics.

Comparison of DNA Damage and Oxidative Stress in Patients Anesthetized With Desflurane Associated or Not With Nitrous Oxide: A Prospective Randomized Clinical Trial.

BACKGROUND: Little is known about the effects of desflurane associated or not with nitrous oxide (N2O) on oxidative stress and patient genetic material. The aim of this study was to compare the effects of anesthesia maintained with desflurane associated or not with N2O on DNA damage (as a primary outcome) and oxidative stress (as a secondary outcome) in patients who underwent an elective minimally invasive surgery. METHODS: This prospective randomized clinical trial analyzed 40 patients of both sexes with an American Society of Anesthesiologists physical status I who were 18-50 years of age and scheduled for septoplasty. The patients were randomly allocated into 2 groups according to anesthesia maintenance as follows: desflurane (n = 20) or desflurane/N2O (n = 20). Blood samples were collected before anesthesia (T1 = baseline), 1.5 hours after anesthesia induction (T2), and on the morning of the postoperative first day (T3). Basal and oxidative DNA damage (determined using formamidopyrimidine DNA glycosylase to detect oxidized purines and endonuclease III to detect oxidized pyrimidines) were evaluated using the comet assay. Oxidative stress markers were evaluated based on lipid peroxidation (by assessing 4-hydroxynonenal and 8-iso-prostaglandin F2α [8-isoprostane] using enzyme linked immunosorbent immunoassay), protein carbonyls (assessed by enzyme linked immunosorbent immunoassay), and antioxidant defense (ferric-reducing antioxidant power by spectrophotometry). The effect size was expressed as the mean differences between groups and the corresponding 95% confidence interval (CI). RESULTS: There was no significant mean difference between groups in relation to DNA damage (-1.7 [95% CI, -7.0 to 3.5]), oxidized DNA pyrimidines (-1.8 [95% CI, -12.5 to 8.9]) and purines (-1.9 [95% CI, -13.9 to 10.1]), 4-hydroxynonenal (-0.2 [95% CI, -2.8 to 2.4]), 8-isoprostane (549 [95% CI, -2378 to 3476]), protein carbonyls (0.2 [95% CI, -2.1 to 2.3]), or ferric-reducing antioxidant power (24 [95% CI, -52.0 to 117.2]). CONCLUSIONS: The coadministration of 60% N2O with desflurane did not seem to impair the effects on DNA or the redox status compared with desflurane anesthesia, suggesting that both studied anesthetic techniques can be suitable options for healthy individuals who undergo minimally invasive surgery lasting at least 1.5 hours. However, due to the low power of the study, more research is necessary to confirm our findings.

Laryngeal Mask Airway Versus Other Airway Devices for Anesthesia in Children With an Upper Respiratory Tract Infection: A Systematic Review and Meta-analysis of Respiratory Complications.

There is an association between upper respiratory tract infection (URTI) and an increased incidence of perioperative respiratory adverse events (PRAEs), which is a major risk for morbidity during pediatric anesthesia. The aim of the present study was to compare the risk of PRAEs among different airway devices during anesthesia in children with a URTI. A systematic review according to the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was conducted. Only randomized clinical trials evaluating anesthesia in children with a URTI and who were submitted to any of the airway devices were included. From 1030 studies identified, 5 randomized clinical trials were included in the final analysis. There were no statistical differences between laryngeal mask airway (LMA®) and endotracheal tube (ETT) regarding breath holding or apnea (risk ratio [RR], 0.82; 95% confidence interval [CI], 0.41-1.65), laryngospasm (RR, 0.74; 95% CI, 0.18-2.95), and arterial oxygen desaturation (RR, 0.44; 95% CI, 0.16-1.17). The quality of evidence was low for the first outcome and very low for the 2 other outcomes, respectively. The LMA use produced a significant reduction of cough (RR, 0.75; 95% CI, 0.58-0.96, low quality of evidence) compared with ETT. The ideal airway management in children with a URTI remains obscure given that there are few data of perioperative respiratory complications during anesthesia. This systematic review demonstrates that LMA use during anesthesia in children with URTI did not result in decrease of the most feared PRAEs. However, LMA was better than ETT in reducing cough. Further research is needed to define the risks more clearly because cough and laryngospasm have similar triggers, and both bronchospasm and laryngospasm trigger cough.

Effects of different fresh gas flows with or without a heat and moisture exchanger on inhaled gas humidity in adults undergoing general anaesthesia: A systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: The minimum inhaled gas absolute humidity level is 20 mgH2O l for short-duration use in general anaesthesia and 30 mgH2O l for long-duration use in intensive care to avoid respiratory tract dehydration. OBJECTIVE: The aim is to compare the effects of different fresh gas flows (FGFs) through a circle rebreathing system with or without a heat and moisture exchanger (HME) on inhaled gas absolute humidity in adults undergoing general anaesthesia. DESIGN: Systematic review and meta-analyses of randomised controlled trials. We defined FGF (l min) as minimal (0.25 to 0.5), low (0.6 to 1.0) or high (≥2). We extracted the inhaled gas absolute humidity data at 60 and 120 min after connection of the patient to the breathing circuit. The effect size is expressed as the mean differences and corresponding 95% confidence intervals (CI). DATA SOURCES: PubMed, EMBASE, SciELO, LILACS and CENTRAL until January 2017. RESULTS: We included 10 studies. The inhaled gas absolute humidity was higher with minimal flow compared with low flow at 120 min [mean differences 2.51 (95%CI: 0.32 to 4.70); P = 0.02] but not at 60 min [mean differences 2.95 (95%CI: -0.95 to 6.84); P = 0.14], and higher with low flow compared with high flow at 120 min [mean differences 7.19 (95%CI: 4.53 to 9.86); P < 0.001]. An inhaled gas absolute humidity minimum of 20 mgH2O l was attained with minimal flow at all times but not with low or high flows. An HME increased the inhaled gas absolute humidity: with minimal flow at 120 min [mean differences 8.49 (95%CI: 1.15 to 15.84); P = 0.02]; with low flow at 60 min [mean differences 9.87 (95%CI: 3.18 to 16.57); P = 0.04] and 120 min [mean differences 7.19 (95%CI: 3.29 to 11.10); P = 0.003]; and with high flow of 2 l min at 60 min [mean differences 6.46 (95%CI: 4.05 to 8.86); P < 0.001] and of 3 l min at 120 min [mean differences 12.18 (95%CI: 6.89 to 17.47); P < 0.001]. The inhaled gas absolute humidity data attained or were near 30 mgH2O l when an HME was used at all FGFs and times. CONCLUSION: All intubated patients should receive a HME with low or high flows. With minimal flow, a HME adds cost and is not needed to achieve an appropriate inhaled gas absolute humidity.

Zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance.

BACKGROUND: Diabetes is associated with long-term damage, dysfunction and failure of various organs, especially the eyes, kidneys, nerves, heart and blood vessels. The risk of developing type 2 diabetes increases with age, obesity and lack of physical activity. Insulin resistance is a fundamental aspect of the aetiology of type 2 diabetes. Insulin resistance has been shown to be associated with atherosclerosis, dyslipidaemia, glucose intolerance, hyperuricaemia, hypertension and polycystic ovary syndrome. The mineral zinc plays a key role in the synthesis and action of insulin, both physiologically and in diabetes mellitus. Zinc seems to stimulate insulin action and insulin receptor tyrosine kinase activity. OBJECTIVES: To assess the effects of zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance. SEARCH METHODS: This review is an update of a previous Cochrane systematic review published in 2007. We searched the Cochrane Library (2015, Issue 3), MEDLINE, EMBASE, LILACS and the ICTRP trial register (from inception to March 2015). There were no language restrictions. We conducted citation searches and screened reference lists of included studies. SELECTION CRITERIA: We included studies if they had a randomised or quasi-randomised design and if they investigated zinc supplementation compared with placebo or no intervention in adults with insulin resistance living in the community. DATA COLLECTION AND ANALYSIS: Two review authors selected relevant trials, assessed risk of bias and extracted data. MAIN RESULTS: We included three trials with a total of 128 participants in this review. The duration of zinc supplementation ranged between four and 12 weeks. Risk of bias was unclear for most studies regarding selection bias (random sequence generation, allocation concealment) and detection bias (blinding of outcome assessment). No study reported on our key outcome measures (incidence of type 2 diabetes mellitus, adverse events, health-related quality of life, all-cause mortality, diabetic complications, socioeconomic effects). Evaluation of insulin resistance as measured by the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) showed neutral effects when comparing zinc supplementation with control (two trials; 114 participants). There were neutral effects for trials comparing zinc supplementation with placebo for total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides (2 studies, 70 participants). The one trial comparing zinc supplementation with exercise also showed neutral effects for total cholesterol, HDL and LDL cholesterol, and a mean difference in triglycerides of -30 mg/dL (95% confidence interval (CI) -49 to -10) in favour of zinc supplementation (53 participants). Various surrogate laboratory parameters were also analysed in the included trials. AUTHORS' CONCLUSIONS: There is currently no evidence on which to base the use of zinc supplementation for the prevention of type 2 diabetes mellitus. Future trials should investigate patient-important outcome measures such as incidence of type 2 diabetes mellitus, health-related quality of life, diabetic complications, all-cause mortality and socioeconomic effects.

Dexmedetomidine on renal ischemia-reperfusion injury in rats: assessment by means of NGAL and histology.

BACKGROUND: Ischemic acute kidney injury is a common occurrence in the perioperative period and in critical patients admitted to intensive care units. The reestablishment of blood supply may worsen injury through the ischemia-reperfusion (I/R) mechanism. We investigated the effect of dexmedetomidine on the kidneys of rats subjected to an experimental I/R model. METHODS: 34 rats anesthetized with isoflurane was undergone right nephrectomy and randomly assigned to four groups: Control C (saline solution); Dexmedetomidine D (dexmedetomidine); Sham S (saline solution); Sham with Dexmedetomidine SD (dexmedetomidine). The serum levels of neutrophil gelatinase-associated lipocalin (NGAL) were measured at time-points T1 (following stabilization), T2 (ischemia), T3 (reperfusion), T4 (12 h after of I/R). The kidneys were subjected to histological examination. RESULTS: The NGAL levels were significantly higher at T4 compared with T1. Upon histological examination, the left kidneys in groups C and D exhibited a similar extent of cell injury. CONCLUSION: The levels of NGAL did not indicate either protection against or worsening of kidney injury. Histological examination for acute tubular necrosis showed that dexmedetomidine did not protect the kidneys from I/R.

The humidity in a Dräger Primus anesthesia workstation using low or high fresh gas flow and with or without a heat and moisture exchanger in pediatric patients.

BACKGROUND: An inhaled gas absolute humidity of 20 mg H2O·L is the value most considered as the threshold necessary for preventing the deleterious effects of dry gas on the epithelium of the airways during anesthesia. Because children have small minute ventilation, we hypothesized that the humidification of a circle breathing system is lower in children compared with adults. The Primus anesthesia workstation (Dräger Medical, Lübeck, Germany) has a built-in hotplate to heat the patient's exhaled gases. A heat and moisture exchanger (HME) is a device that can be used to further humidify and heat the inhaled gases during anesthesia. To evaluate the humidifying properties of this circle breathing system during pediatric anesthesia, we compared the temperature and humidity of inhaled gases under low or high fresh gas flow (FGF) conditions and with or without an HME. METHODS: Forty children were randomly allocated into 4 groups according to the ventilation of their lungs by a circle breathing system in a Dräger Primus anesthesia workstation with low (1 L·min) or high (3 L·min) FGF without an HME (1L and 3L groups) or with an HME (Pall BB25FS, Pall Biomedical, East Hills, NY; HME1L and HME3L groups). The temperature and absolute humidity of inhaled gases were measured at 10, 20, 40, 60, and 80 minutes after connecting the patient to the breathing circuit. RESULTS: The mean inhaled gas temperature was higher in HME groups (HME1L: 30.3°C ± 1.1°C; HME3L: 29.3°C ± 1.2°C) compared with no-HME groups (1L: 27.0°C ± 1.2°C; 3L: 27.1°C ± 1.5°C; P < 0.0001). The mean inhaled gas absolute humidity was higher in HME than no-HME groups and higher in low-flow than high-flow groups ([HME1L: 25 ± 1 mg H2O·L] > [HME3L: 23 ± 2 mg H2O·L] > [1L: 17 ± 1 mg H2O·L] > [3L: 14 ± 1 mg H2O·L]; P < 0.0001). CONCLUSIONS: In a pediatric circle breathing system, the use of neither high nor low FGF provides the minimum humidity level of the inhaled gases thought to reduce the risk of dehydration of airways. Insertion of an HME increases the humidity and temperature of the inhaled gases, bringing them closer to physiological values. The use of a low FGF enhances the HME efficiency and consequently increases the inhaled gas humidity values. Therefore, the association of an HME with low FGF in the breathing circuit is the most efficient way to conserve the heat and the moisture of the inhaled gas during pediatric anesthesia.

Air versus saline in the loss of resistance technique for identification of the epidural space.

BACKGROUND: The success of epidural anaesthesia depends on correct identification of the epidural space. For several decades, the decision of whether to use air or physiological saline during the loss of resistance technique for identification of the epidural space has been governed by the personal experience of the anaesthesiologist. Epidural block remains one of the main regional anaesthesia techniques. It is used for surgical anaesthesia, obstetrical analgesia, postoperative analgesia and treatment of chronic pain and as a complement to general anaesthesia. The sensation felt by the anaesthesiologist from the syringe plunger with loss of resistance is different when air is compared with saline (fluid). Frequently fluid allows a rapid change from resistance to non-resistance and increased movement of the plunger. However, the ideal technique for identification of the epidural space remains unclear. OBJECTIVES: • To evaluate the efficacy and safety of both air and saline in the loss of resistance technique for identification of the epidural space.• To evaluate complications related to the air or saline injected. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 9), MEDLINE, EMBASE and the Latin American and Caribbean Health Science Information Database (LILACS) (from inception to September 2013). We applied no language restrictions. The date of the most recent search was 7 September 2013. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-randomized controlled trials (quasi-RCTs) on air and saline in the loss of resistance technique for identification of the epidural space. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality and extracted data. MAIN RESULTS: We included in the review seven studies with a total of 852 participants. The methodological quality of the included studies was generally ranked as showing low risk of bias in most domains, with the exception of one study, which did not mask participants. We were able to include data from 838 participants in the meta-analysis. We found no statistically significant differences between participants receiving air and those given saline in any of the outcomes evaluated: inability to locate the epidural space (three trials, 619 participants) (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.33 to 2.31, low-quality evidence); accidental intravascular catheter placement (two trials, 223 participants) (RR 0.90, 95% CI 0.33 to 2.45, low-quality evidence); accidental subarachnoid catheter placement (four trials, 682 participants) (RR 2.95, 95% CI 0.12 to 71.90, low-quality evidence); combined spinal epidural failure (two trials, 400 participants) (RR 0.98, 95% CI 0.44 to 2.18, low-quality evidence); unblocked segments (five studies, 423 participants) (RR 1.66, 95% CI 0.72 to 3.85); and pain measured by VAS (two studies, 395 participants) (mean difference (MD) -0.09, 95% CI -0.37 to 0.18). With regard to adverse effects, we found no statistically significant differences between participants receiving air and those given saline in the occurrence of paraesthesias (three trials, 572 participants) (RR 0.89, 95% CI 0.69 to 1.15); difficulty in advancing the catheter (two trials, 227 participants) (RR 0.91, 95% CI 0.32 to 2.56); catheter replacement (two trials, 501 participants) (RR 0.69, 95% CI 0.26 to 1.83); and postdural puncture headache (one trial, 110 participants) (RR 0.83, 95% CI 0.12 to 5.71). AUTHORS' CONCLUSIONS: Low-quality evidence shows that results do not differ between air and saline in terms of the loss of resistance technique for identification of the epidural space and reduction of complications. Applicability might be compromised, as most of the results described in this review were obtained from parturient patients. This review underlines the need to conduct well-designed trials in this field. 

Incentive spirometry for prevention of postoperative pulmonary complications in upper abdominal surgery.

BACKGROUND: This is an update of a Cochrane Review first published in The Cochrane Library 2008, Issue 3.Upper abdominal surgical procedures are associated with a high risk of postoperative pulmonary complications. The risk and severity of postoperative pulmonary complications can be reduced by the judicious use of therapeutic manoeuvres that increase lung volume. Our objective was to assess the effect of incentive spirometry compared to no therapy or physiotherapy, including coughing and deep breathing, on all-cause postoperative pulmonary complications and mortality in adult patients admitted to hospital for upper abdominal surgery. OBJECTIVES: Our primary objective was to assess the effect of incentive spirometry (IS), compared to no such therapy or other therapy, on postoperative pulmonary complications and mortality in adults undergoing upper abdominal surgery.Our secondary objectives were to evaluate the effects of IS, compared to no therapy or other therapy, on other postoperative complications, adverse events, and spirometric parameters. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 8), MEDLINE, EMBASE, and LILACS (from inception to August 2013). There were no language restrictions. The date of the most recent search was 12 August 2013. The original search was performed in June 2006. SELECTION CRITERIA: We included randomized controlled trials (RCTs) of IS in adult patients admitted for any type of upper abdominal surgery, including patients undergoing laparoscopic procedures. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. MAIN RESULTS: We included 12 studies with a total of 1834 participants in this updated review. The methodological quality of the included studies was difficult to assess as it was poorly reported, so the predominant classification of bias was 'unclear'; the studies did not report on compliance with the prescribed therapy. We were able to include data from only 1160 patients in the meta-analysis. Four trials (152 patients) compared the effects of IS with no respiratory treatment. We found no statistically significant difference between the participants receiving IS and those who had no respiratory treatment for clinical complications (relative risk (RR) 0.59, 95% confidence interval (CI) 0.30 to 1.18). Two trials (194 patients) IS compared incentive spirometry with deep breathing exercises (DBE). We found no statistically significant differences between the participants receiving IS and those receiving DBE in the meta-analysis for respiratory failure (RR 0.67, 95% CI 0.04 to 10.50). Two trials (946 patients) compared IS with other chest physiotherapy. We found no statistically significant differences between the participants receiving IS compared to those receiving physiotherapy in the risk of developing a pulmonary condition or the type of complication. There was no evidence that IS is effective in the prevention of pulmonary complications. AUTHORS' CONCLUSIONS: There is low quality evidence regarding the lack of effectiveness of incentive spirometry for prevention of postoperative pulmonary complications in patients after upper abdominal surgery. This review underlines the urgent need to conduct well-designed trials in this field. There is a case for large RCTs with high methodological rigour in order to define any benefit from the use of incentive spirometry regarding mortality.

Pediatric perioperative cardiac arrest and mortality: a study from a tertiary teaching hospital.

OBJECTIVES: A previous survey performed in our institution demonstrated perioperative pediatric cardiac arrest and mortality rates of 22.9 and 9.8 per 10,000 anesthetics, respectively, and an anesthesia-related cardiac arrest rate of 4.58 per 10,000 anesthetics. Changes in pediatric practices (i.e., safer anesthesia techniques and change in population) may have altered cardiac arrest rates. The aim of this investigation was to reexamine the perioperative and anesthesia-related cardiac arrest rates, causes, and outcomes in a Brazilian institution. DESIGN: Observational study. SETTING: Tertiary teaching hospital. PATIENTS: Children less than 18 years old, who were administered an anesthetic between January 1, 2005, and December 31, 2010, were included in this study. The cardiac arrest cases were identified from an anesthesia database. The data included children's characteristics, surgical procedures, American Society of Anesthesiologists physical status classification, surgical areas, and surgery type. The outcomes were perioperative cardiac arrest and mortality and anesthesia-related (totally or partially) cardiac arrest and mortality. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 10,649 anesthetics during the study period, with 22 perioperative cardiac arrests and 11 deaths (20.65 and 10.32 per 10,000 anesthetics, respectively). A high incidence of perioperative cardiac arrest occurred in American Society of Anesthesiologists IV-V neonates and infants who underwent emergency surgery. There were no perioperative cardiac arrests in children aged 13 through 17, no anesthesia-related cardiac arrest in American Society of Anesthesiologists I-III children, and no totally anesthesia-related cardiac arrest. The anesthesia-related cardiac arrest rate was 2.81 per 10,000 anesthetics, with no anesthesia-related mortality. Respiratory events accounted for all of the anesthesia-related cardiac arrests. CONCLUSIONS: Despite the improvements achieved in the pediatric anesthesia safety in our institution, the perioperative cardiac arrest rates are still high and similar to the developing countries rates, with the child's disease or condition being the most important trigger for cardiac arrest. Airway management continues to be the greatest cause of anesthesia-related cardiac arrest.

Modulation of gene expression and influence of gene polymorphisms related to genotoxicity and redox status on occupational exposure to inhaled anesthetics.

The extensive use of inhalational anesthetics contributes to both indoor and outdoor (environmental) pollution. The influence of genetic susceptibility on DNA damage and oxidative stress and the possible modulation of gene expression have not yet been investigated upon occupational exposure to waste anesthetic gases (WAGs). This study assessed 8-oxoguanine DNA glycosylase 1 (OGG1) and superoxide dismutase 2 (SOD2) gene expression, which are related to oxidized DNA repair and antioxidant capacity, respectively, and the influence of their polymorphisms (OGG1 rs1052133 and SOD2 rs4880) in 100 professionals highly exposed to WAGs and 93 unexposed volunteers (control group). Additionally, X-ray repair cross complementing 1 (XRCC1 rs25487 and rs1799782) and ataxia telangiectasia mutated (ATM rs600931) gene polymorphisms as well as genetic instability (micronucleus-MN and nuclear bud-NBUD) and oxidative stress (malondialdehyde-MDA and ferric reducing antioxidant power-FRAP) biomarkers were assessed in the groups (control and exposed) and in the subgroups of the exposed group according to job occupation (anesthesiologists versus surgeons/technicians). Except for the ATM TT controls (associated with increased FRAP), there were no influences of OGG1, XRCC1, ATM, and SOD2 polymorphisms on MN, NBUD, MDA, and FRAP values in exposed or control subjects. No significant difference in the expression of either gene evaluated (OGG1 and SOD2) was found between the exposed and control groups. Increased OGG1 expression was observed among OGG1 -/Cys individuals only in the control group. Among the exposed group, anesthesiologists had a greater duration of WAG exposure (both h/week and years) than surgeons/technicians, which was associated with increased MDA and decreased antioxidant capacity (FRAP) and SOD2 expression (redox status). Higher expression of OGG1 was found in -/Cys surgeons/technicians than in anesthesiologists with the same genotype. Increased antioxidant capacity was noted in the surgeons/technicians carrying the ATM T allele and in those carrying XRCC1 -/Gln. Increased MN was influenced by OGG1 -/Cys in surgeons/technicians. Anesthesiologists with ATM CC exhibited increased MN, and those carrying the C allele (CC/CT genotype) exhibited increased NBUD. SOD2 polymorphism did not seem to be relevant for WAG exposure. These findings contribute to advancing the knowledge on genetic susceptibility/gene expression/genetic instability/oxidative stress, including differences in job occupation considering the workload, in response to occupational exposure to WAGs.

Veterinarians exposed to inhaled anesthetic present chromosome damage, apoptosis and cell cycle changes.

This cross-sectional study evaluated, for the first time, DNA damage, viability, and cell death of lymphocytes and cell cycle phases of mononuclear and polymorphonuclear cells in veterinarians exposed to the volatile anesthetic isoflurane. Veterinarians who were occupationally exposed to isoflurane (exposed group; n = 20) and matched-unexposed individuals (volunteers without occupational exposure; n = 20) were enrolled in the study. DNA damage was assessed in lymphocytes by micronucleus (MN) and phosphorylated histone gamma-H2AX (γ-H2AX). Cell viability, cytotoxicity, and the cell cycle were evaluated by flow cytometry. Isoflurane was detected in urine samples by headspace gas chromatography-mass spectrometry. Compared with unexposed subjects, veterinarians occupationally exposed to isoflurane (25.7 ± 23.7 µg/L urine) presented statistically higher MN frequencies, lymphocytic apoptosis rates, and numbers of polymorphonuclear cells in the G0/G1 stage. Additionally, the exposed group presented statistically lower proportions of viable lymphocytes and G2/M polymorphonuclear cells. Our findings indicate that veterinarians who are frequently exposed to inhaled anesthetic exhibit chromosomal and cell damage in addition to changes in peripheral blood cell proliferation.

Comparison between inhalational anesthetics in terms of DNA damage and immunological markers.

This study compared genetic damage and immunological markers between surgical patients who underwent inhalational anesthesia with isoflurane or sevoflurane. Blood samples were collected from surgical patients (n = 18 in the isoflurane group and n = 17 in the sevoflurane group) at baseline (before the anesthesia procedure) and the day after anesthesia. DNA damage was detected using an alkaline comet assay; proinflammatory interleukin (IL)-6 was detected by flow cytometry, and white blood cells were detected via an automatic hematology analyzer. The characteristics of both groups were similar, and neither of the two anesthetics induced DNA damage. Similarly, mild neutrophilia was observed after anesthesia in both groups. Increased IL-6 levels were observed 1 day after anesthesia regardless of the type of anesthetic, but this increase was greater in the isoflurane group. Our study suggested that isoflurane and sevoflurane administration may contribute to changes in the immune parameters measured, though no genotoxic hazard was identified, in healthy adult patients who undergo low-stress surgery.

Global neonatal perioperative mortality: A systematic review and meta-analysis.

STUDY OBJECTIVE: There are large differences in health care among countries. A higher perioperative mortality rate (POMR) in neonates than in older children and adults has been recognized worldwide. The aim of this study was to provide a systematic review of published 24-h and 30-day POMRs in neonates from 2011 to 2022 in countries with different Human Development Index (HDI) levels. DESIGN AND SETTING: A systematic review with a meta-analysis of studies that reported 24-h and 30-day POMRs in neonates was performed. We searched the databases from January 2011 to July 30, 2022. MEASUREMENTS: The POMRs (per 10,000 procedures under anesthesia) were analyzed according to country HDI. The HDI levels ranged from 0 to 1, representing the lowest and highest levels, respectively (very-high-HDI: ≥ 0.800, high-HDI: 0.700-0.799, medium-HDI: 0.550-0.699, and low-HDI: < 0.550). The magnitude of the POMRs by country HDI was studied using meta-analysis. MAIN RESULTS: Eighteen studies from 45 countries were included. The 24-h (n = 96 deaths) and 30-day (n = 459 deaths) POMRs were analyzed from 33,729 anesthetic procedures. The odds ratios (ORs) of the 24-h POMR in low-HDI countries were higher than those in very-high- (OR 8.4, 95% CI 1.7-40.4; p = 0.008), high- (OR 7.3, 95% CI 2.2-24.4; p = 0.001) and medium-HDI countries (OR 7.7, 95% CI 3.1-18.7; p < 0.0001) but with no odds differences between very-high- and high-HDI countries (p = 0.879), very-high- and medium-HDI countries (p = 0.915) and high- and medium-HDI countries (p = 0.689). The odds of a 30-day POMR in low-HDI countries were higher than those in very-high-HDI countries (OR 6.9, 95% CI 1.9-24.6; p = 0.002) but not in high-HDI countries (OR 1.4, 95% CI 0.6-3.0; p = 0.396). CONCLUSIONS: The review demonstrated very high global POMRs in a surgical population of neonates independent of the country HDI level. We identified differences in 24-h and 30-day POMRs between low-HDI countries and other countries with higher HDI levels.

Modulation of gene expression and inflammation but not DNA damage after sevoflurane anesthesia.

This study assessed, for the first time, the expression of the genes hOGG1, TP53, and IL-6 in leukocytes by real-time quantitative polymerase chain reaction in surgical patients before (baseline), during (2 h of anesthesia) and 1 day after sevoflurane anesthesia. Additionally, DNA damage was detected by the comet assay, serum interleukin (IL)-6 was detected by flow cytometry, and differential leukocyte counting was also performed. TP53 and hOGG1 expression was downregulated on the day after anesthesia compared to before anesthesia. However, IL-6 expression did not change, and no DNA damage induction was observed during or after anesthesia. At the systemic level, mild neutrophilia and an increase in IL-6 levels occurred after anesthesia. Our findings suggest that sevoflurane anesthesia downregulates gene expression (hOGG1 and TP53) and contributes to an inflammatory status (increased systemic IL-6 and mild neutrophilia) but is not associated with DNA damage in patients without comorbidities who undergo minor elective surgery.

Evaluation of genetic instability, oxidative stress, and metabolism-related gene polymorphisms in workers exposed to waste anesthetic gases.

Professionals who work in operating rooms (ORs) may be exposed daily to waste anesthetic gases (WAGs) due to the use of inhalational anesthetics. Considering the controversial findings related to genetic damage and redox status in addition to a lack of knowledge about the effect of polymorphisms in genes related to phase I and II detoxification upon occupational exposure to WAGs, this cross-sectional study is the first to jointly evaluate biomarkers of genetic instability, oxidative stress, and susceptibility genes in professionals occupationally exposed to high trace amounts of halogenated (≥ 7 ppm) and nitrous oxide (165 ppm) anesthetics in ORs and in individuals not exposed to WAGs (control group). Elevated rates of buccal micronucleus (MN) and nuclear bud (NBUD) were observed in the exposure group and in professionals exposed aged more than 30 years. Exposed males showed a higher antioxidant capacity, as determined by the ferric reducing antioxidant power (FRAP), than exposed females; exposed females had higher frequencies of MN and NBUD than nonexposed females. Genetic instability (MN) was observed in professionals with greater weekly WAG exposure, and those exposed for longer durations (years) exhibited oxidative stress (increased lipid peroxidation and decreased FRAP). Polymorphisms in metabolic genes (cytochrome P450 2E1 (CYP2E1) and glutathione S-transferases (GSTs)) did not exert an effect, except for the effects of the GSTP1 (rs1695) AG/GG polymorphism on FRAP (both groups) and GSTP1 AG/GG and GSTT1 null polymorphisms, which were associated with greater FRAP values in exposed males. Minimizing WAG exposure is necessary to reduce impacts on healthcare workers.