Perioperative cardiac arrest and mortality in trauma patients: A systematic review of observational studies.

STUDY OBJECTIVE: Factors that influence the occurrence of perioperative cardiac arrest (CA) and its outcomes in trauma patients are not well known. The novelty of our study lies in the performance of a systematic review conducted worldwide on the occurrence of perioperative CA and/or mortality in trauma patients. DESIGN: A systematic review was performed to identify observational studies that reported the occurrence of CA and/or mortality due to trauma and CA and/or mortality rates in trauma patients up to 24 h postoperatively. We searched the MEDLINE, EMBASE, LILACS and SciELO databases through January 29, 2020. SETTING: Perioperative period. MEASUREMENTS: The primary outcomes evaluated were data on the epidemiology of perioperative CA and/or mortality in trauma patients. MAIN RESULTS: Nine studies were selected, with the first study being published in 1994 and the most recent being published in 2019. Trauma was an important factor in perioperative CA and mortality, with rates of 168 and 74 per 10,000 anesthetic procedures, respectively. The studies reported a higher proportion of perioperative CA and mortality in trauma patients who were males, young adults and adults, patients with American Society of Anesthesiologists (ASA) physical status ≥ III, patients undergoing general anesthesia, and in abdominal or neurological surgeries. Uncontrolled hemorrhage was the main cause of perioperative CA and mortality after trauma. Survival rates after perioperative CA were low. CONCLUSIONS: Trauma is an important factor in perioperative CA and mortality, especially in young adult and adult males and in patients classified as having an ASA physical status ≥ III mainly due to uncontrollable bleeding after blunt and perforating injuries. Trauma is a global public health problem and has a strong impact on perioperative morbidity and mortality.

Psychological preparation reduces preoperative anxiety in children. Randomized and double-blind trial / Preparação psicológica reduz ansiedade pré-operatória de crianças. Ensaio randomizado e duplamente encoberto

Abstract Objective: To verify the effect of psychological preparation on the relief of preoperative anxiety in children and to correlate parents' and children's levels of anxiety. Method: After the approval of the institutional Research Ethics Committee and written consent of the children's parents or guardians, 118 children of both genders were prospectively selected, aged between 2 and 8 years, physical condition classification ASA I, who were treated in the pre-anesthetic evaluation ambulatory of the University Hospital and who underwent ambulatory surgeries at the same hospital. Two controlled groups of 59 children were randomized: control group basic preparation and psychological preparation group. On the day of surgery, all selected children were evaluated regarding their level of anxiety using the modified Yale Preoperative Anxiety Scale and their parents were evaluated regarding their level of anxiety through the Visual Analog Scale. The evaluator was blinded to which study group the child and family member belonged to. Results: Nine children and their family members were excluded per group when the results were analyzed. Children from the prepared group showed significant reductions in their level of anxiety in relation to the control group (p = 0.04). There was no correlation between the level of anxiety of children and their parents' levels (p = 0.78). Conclusion: The psychological preparation was effective in reducing the level of anxiety of children. However, there was no relation between the level of anxiety of children and their parents' level.

Resumo: Objetivos: Verificar o efeito da preparação psicológica no alívio da ansiedade pré-operatória de crianças e avaliar se há correlação com a ansiedade dos pais. Método: Após a aprovação do Comitê de Ética e Pesquisa da Faculdade de Medicina e obtenção do consentimento pelos responsáveis dos pacientes, foram selecionadas prospectivamente 118 crianças, de ambos os sexos, entre dois e oito anos, classificação de estado físico ASA I, atendidas no ambulatório de avaliação pré-anestésica do Hospital Universitário e submetidas a cirurgias ambulatoriais. Foram randomizados dois grupos controlados de 59 crianças: grupo de preparação básica e grupo de preparação psicológica. No dia da cirurgia, todas as crianças foram avaliadas em relação ao seu grau de ansiedade através da Escala de Ansiedade Pré-operatória de Yale Modificada e seus pais, avaliados quanto ao seu nível de ansiedade pela Escala Visual Analógica. O avaliador era cego sobre qual grupo do estudo a criança e seu familiar pertenciam. Resultados: Na análise dos resultados, foram excluídas nove crianças e familiares de cada grupo. As crianças do grupo preparado tiveram reduções significativas no grau de ansiedade em relação ao grupo controle, (p = 0,04). Não houve correlação entre os graus de ansiedade das crianças e seus pais (p = 0,78). Conclusão: A preparação psicológica foi eficaz na redução do grau de ansiedade das crianças no momento da cirurgia. Não houve, entretanto, relação entre os graus de ansiedade dos pais e seus filhos.

Psychological preparation reduces preoperative anxiety in children. Randomized and double-blind trial.

OBJECTIVE: To verify the effect of psychological preparation on the relief of preoperative anxiety in children and to correlate parents' and children's levels of anxiety. METHOD: After the approval of the institutional Research Ethics Committee and written consent of the children's parents or guardians, 118 children of both genders were prospectively selected, aged between 2 and 8 years, physical condition classification ASA I, who were treated in the pre-anesthetic evaluation ambulatory of the University Hospital and who underwent ambulatory surgeries at the same hospital. Two controlled groups of 59 children were randomized: control group basic preparation and psychological preparation group. On the day of surgery, all selected children were evaluated regarding their level of anxiety using the modified Yale Preoperative Anxiety Scale and their parents were evaluated regarding their level of anxiety through the Visual Analog Scale. The evaluator was blinded to which study group the child and family member belonged to. RESULTS: Nine children and their family members were excluded per group when the results were analyzed. Children from the prepared group showed significant reductions in their level of anxiety in relation to the control group (p=0.04). There was no correlation between the level of anxiety of children and their parents' levels (p=0.78). CONCLUSION: The psychological preparation was effective in reducing the level of anxiety of children. However, there was no relation between the level of anxiety of children and their parents' level.

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.

The Humidity in a Low-Flow Dräger Fabius Anesthesia Workstation with or without Thermal Insulation or a Heat and Moisture Exchanger: A Prospective Randomized Clinical Trial.

BACKGROUND: During anesthesia, as compared with intensive care, the time of the tracheal intubation is much shorter. An inhaled gas minimum humidity of 20 mgH2O.L-1 is recommended to reduce the deleterious effects of dry gas on the airways during anesthesia with tracheal intubation. The Fabius GS Premium® anesthesia workstation (Dräger Medical, Lübeck, Germany) has a built-in hotplate to heat gases in the breathing circuit. A heat and moisture exchanger (HME) is used to further heat and humidify the inhaled gas. The humidity of the gases in the breathing circuit is influenced by the ambient temperature. We compared the humidity of the inhaled gases from a low-flow Fabius anesthesia workstation with or without thermal insulation (TI) of the breathing circuit and with or without an HME. METHODS: We conducted a prospective randomized trial in 41 adult female patients who underwent elective abdominal surgery. The patients were allocated into four groups according to the devices used to ventilate their lungs using a Dräger Fabius anesthesia workstation with a low gas flow (1 L.min-1): control, with TI, with an HME or with TI and an HME (TIHME). The mean temperature and humidity of the inhaled gases were measured during 2-h after connecting the patients to the breathing circuit. RESULTS: The mean inhaled gas temperature and absolute humidity were higher in the HME (29.2±1.3°C; 28.1±2.3 mgH2O·L-1) and TIHME (30.1±1.2°C; 29.4±2.0 mgH2O·L-1) groups compared with the control (27.5±1.0°C; 25.0±1.8 mgH2O·L-1) and TI (27.2±1.1°C; 24.9±1.8 mgH2O·L-1) groups (P = 0.003 and P<0.001, respectively). CONCLUSIONS: The low-flow Fabius GS Premium breathing circuit provides the minimum humidity level of inhaled gases to avoid damage to the tracheobronchial epithelia during anesthesia. TI of the breathing circuit does not increase the humidity of the inhaled gases, whereas inserting an HME increases the moisture of the inhaled gases closer to physiological values.

Association of increased morbidity with the occurrence of hyperglycemia in the immediate postoperative period after elective pediatric neurosurgery.

OBJECTIVE The acute elevation of blood glucose in perioperative pediatric patients subjected to cardiac surgery and in victims of head trauma is associated with higher rates of postoperative complications. Data on the occurrence of hyperglycemia and its association with unfavorable outcomes among patients who have undergone elective neurosurgery are scarce in the literature. This study aimed to determine whether the occurrence of hyperglycemia during the perioperative period of elective neurosurgery for the resection of tumors of the CNS in children is associated with increased morbidity. METHODS This retrospective cohort analysis included 105 children up to 12 years of age who underwent elective neurosurgery for resection of supratentorial and infratentorial CNS tumors between January 2005 and December 2010 at the São Rafael Hospital, a tertiary care medical center in Salvador, Brazil. Demographic data and intraoperative and postoperative information were collected from the medical records. Differences in blood glucose levels during the perioperative period were evaluated with nonparametric tests. RESULTS The patients who developed postoperative complications exhibited higher blood glucose levels on admission to the intensive care unit (ICU) (162.0 ± 35.8 mg/dl vs 146.3 ± 43.3 mg/dl; p = 0.016) and peak blood glucose levels on postoperative Day 1 (171.9 ± 30.2 mg/dl vs 156.1 ± 43.2 mg/dl; p = 0.008). Multivariate analysis showed that peak blood glucose levels on postoperative Day 1 were independently associated with a higher odds ratio for postoperative complication (OR 1.05). The occurrence of hyperglycemia (>150 mg/dl) upon admission to the ICU was associated with longer ICU (p = 0.003) and hospital (p = 0.001) stays. CONCLUSIONS The occurrence of hyperglycemia during the postoperative period after elective pediatric neurosurgery for the resection of CNS tumors was associated with longer hospital and ICU stays. Postoperative complications were associated with higher blood glucose levels upon admission to the ICU and higher peak blood glucose on the first postoperative day.

Ischemic Postconditioning and Subanesthetic S(+)-Ketamine Infusion: Effects on Renal Function and Histology in Rats.

BACKGROUND: Ischemic postconditioning (IP) in renal Ischemia reperfusion injury (IRI) models improves renal function after IRI. Ketamine affords significant benefits against IRI-induced acute kidney injury (AKI). The present study investigated the effects of IP and IP associated with subanesthetic S(+)-ketamine in ischemia-reperfusion-induced AKI. METHODS: Forty-one Wistar rats were randomized into four groups: CG (10), control; KG (10), S(+)-ketamine infusion; IPG (10), IP; and KIPG (11), S(+)-ketamine infusion + IP. All rats underwent right nephrectomy. IRI and IP were induced only in IPG and KIPG by left kidney arterial occlusion for 30 min followed by reperfusion for 24 h. Complete reperfusion was preceded by three cycles of 2 min of reocclusion followed by 2 min of reperfusion. Renal function was assessed by measuring serum neutrophil gelatinase-associated lipocalin (NGAL), creatinine, and blood urea nitrogen (BUN). Tubular damage was evaluated by renal histology. RESULTS: Creatinine and BUN were significantly increased. Severe tubular injury was only observed in the groups with IRI (IPG and KIPG), whereas no injury was observed in CG or KG. No significant differences were detected between IPG and KIPG. CONCLUSIONS: No synergic effect of the use of subanesthetic S(+)-ketamine and IP on AKI was observed in this rat model.

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.

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.

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. 

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.

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.

Intravenous versus inhalation anaesthesia for one-lung ventilation.

BACKGROUND: This is an update of a Cochrane Review first published in The Cochrane Library, Issue 2, 2008.The technique called one-lung ventilation can confine bleeding or infection to one lung, prevent rupture of a lung cyst or, more commonly, facilitate surgical exposure of the unventilated lung. During one-lung ventilation, anaesthesia is maintained either by delivering an inhalation anaesthetic to the ventilated lung or by infusing an intravenous anaesthetic. It is possible that the method chosen to maintain anaesthesia may affect patient outcomes. Inhalation anaesthetics may impair hypoxic pulmonary vasoconstriction (HPV) and increase intrapulmonary shunt and hypoxaemia. OBJECTIVES: The objective of this review was to evaluate the effectiveness and safety of intravenous versus inhalation anaesthesia for one-lung ventilation. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL); The Cochrane Library (2012, Issue 11); MEDLINE (1966 to November 2012); EMBASE (1980 to November 2012); Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS, 1982 to November 2012) and ISI web of Science (1945 to November 2012), reference lists of identified trials and bibliographies of published reviews. We also contacted researchers in the field. No language restrictions were applied. The date of the most recent search was 19 November 2012. The original search was performed in June 2006. SELECTION CRITERIA: We included randomized controlled trials and quasi-randomized controlled trials of intravenous (e.g. propofol) versus inhalation (e.g. isoflurane, sevoflurane, desflurane) anaesthesia for one-lung ventilation in both surgical and intensive care participants. We excluded studies of participants who had only one lung (i.e. pneumonectomy or congenital absence of one lung). DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. MAIN RESULTS: We included in this updated review 20 studies that enrolled 850 participants, all of which assessed surgical participants－no studies investigated one-lung ventilation performed outside the operating theatre. No evidence indicated that the drug used to maintain anaesthesia during one-lung ventilation affected participant outcomes. The methodological quality of the included studies was difficult to assess as it was reported poorly, so the predominant classification of bias was 'unclear'. AUTHORS' CONCLUSIONS: Very little evidence from randomized controlled trials suggests differences in participant outcomes with anaesthesia maintained by intravenous versus inhalational anaesthesia during one-lung ventilation. If researchers believe that the type of drug used to maintain anaesthesia during one-lung ventilation is important, they should design randomized controlled trials with appropriate participant outcomes, rather than report temporary fluctuations in physiological variables.

Titulaçäo do sevoflurano utilizando o índice bispectral em anestesia pediátrica: influência da medicaçäo pré-anestesia no tempo de despertar e no consumo de anestésico inalatório / Titration of sevoflurane using the bispectral index in pediatric anesthesia: premedication effects on emergence time and consumption of inhalational anesthesic

Justificativa e objetivos: o suvoflurano é agente inalatório que apresenta baixa solubilidade sanguínea/gás, o que permite rápida induçäo e emergência da anestesia. Sua propriedade de manter a estabilidade cardiovascular o torna ideal para seu uso em anestesia pediátrica. O objetivo desta pesquisa foi avaliar a estabilidade hemodinâmica, o consumo de anestésico inalatório e o tempo de despertar em crianças sem medicaçäo pré-anestésica (MPA) e com MPA (midazolam ou clonidina), anestesiadas com sevoflurano, cujas doses foram tituladas de acordo com monitorizaçäo pelo BIS. Método: foram estudados 30 pacientes com idade entre 2 e 12 anos, estado físico ASA I, submetidos a cirurgias eletivas, divididos em 3 grupos: G1 - sem MPA, G2 - midazolam (0,5mg.kg(elevado a menos 1) e G3 - clonidina (4µg.kg(elevado a menos 1) ambos por via oral 60 minutos antes de serem encaminhados ao centro cirúrgico. Todos os pacientes receberam alfentanil (30µg.kg(elevado a menos 1), propofol (3mg.kg(elevado a menos 1), atracúrio (0,5mg.kg(elevado a menos 1) e sevoflurano em concentraçöes variáveis, monitorizadas pelo BIS (valores próximos a 60) e N2O em sistema sem reinalaçäo. Foram avaliadas as PAS, PAD FC, a concentraçäo expirada (CE) o consumo de sevoflurano (ml.min.(elevado a menos 1), o tempo de despertar - tempo decorrido entre o término da anestesia e a movimentaçäo espontânea do paciente procurando se exturbar, esboçando choro, abrindo olhos e boca. Resultados: os três grupos tiveram o mesmo comportamento com relaçäo à PAS, PAD, CE, ao consumo de sevoflurano e tempo de despertar. A FC foi menor no grupo G3. Conclusöes: o sevoflurano determinou estabilidade hemodinâmica. A MPA com clonidina ou midazolam näo influenciou o tempo de despertar, consumo e a manutençäo da anestesia com sevoflurano. A duraçäo da anestesia também näo influenciou o tempo de despertar. A monitorizaçäo da hipnose foi importante na adequaçäo dos níveis anestésicos, o que pode ter sido fator determinante na homogeneidade do tempo de despertar dos pacientes nos três grupos estudados

Efeitos do sulfato de magnésio na hemodinâmica e funçåo renal de cåes anestesiados com pentobarbital sódico / Effects of magnesium suplhate on the renal hemodynamics and function of dogs anesthezied with pentobarbitone

Background and objectives - The use of magnesium sulphate for the prevention of seizures in pre-eclampsia may induce hypermagnesemia. Clinical and experimental studies are not in agreement about the effects of magnesium on the renal hemodynamics and function. We therefore studied the effects of hypermagnesemia on the renal hemodynamics and function of dogs anesthetized with pentobarbitone. Methods - Sisteen mongrel dogs were anesthetized with pentobarbitone 30mg.Kg-1 and submited to extracellular volume expansion with Ringer's solution (0.4 ml.Kg-1.min-1) and mechanical ventilation with room air. The dogs were allocated into two groups of 8 animals, for the study of renal hemodynamics and following the administration of 5mg.Kg-1 of pentobarbitone (Group 1 - control) or pentobarbitone associated with magnesium selphate in the dose of 140mg.Kg-1, administered in 15 minutes, followed by 80mg.Kg-1.h-1 (Group 2). The parameters studied were: PAH clearance, creatinine clearance, osmolar clearance, free water clearance, renal blood flow, renal vascular resistance, filtration fraction, urinary volume, plasmatic and urinary osmolarity, urinary and fractionary excretion of sodium and potassium, measured at five moments: 15 (M1), 30 (M2), 60 (M3) and 75 (M4) minutes after the first supplementary dose of pentobarbitone and 15 minutes (M5) after second supplementary dose in Group 1. In Group 2, the moments M3, M4, M5 were 15. 30, and 60 minutes after the priming dose of magnesium sulphate and during the maintenance dose. Results - In Group 1 no significant changes were observed in renal hemodynamic parameters and creatinine clearance. The extracellular volume expansion increased urinary volume and decreased urinary osmolarity as a consequence of sodium, potassium and free water clearance. The fractionary excretion of sodium was maintained. The plasmatic osmolarity increased. In Group 2, renal hemodynamic parameters and creatinine clearance were also maintained. There was an increased in renal sodium clearance, as detected by the increased in the fractionary excretion of sodium. Conslusions - Magnesium sulphate did not produce significant changes in renal hemodynamics and facilitated the renal excretion of sodium in dogs anesthetized with pentobarbitone

Efeitos do sulfato de magnésio na hemodinâmica cardiovascular de cåes anestesiados com pentobarbital sódico / Effects of magnesium sulphate on the cardiovascular hemodynamics of dogs anesthetized pentobarbitone

Background and Objectives - A controversy exists in the literature regarding the effects of the acute administration of magnesium on the cardiovascular system of animals and humans. The purpose of this study was to evaluate the effects of hypermagnesemia on the cardiovascular hemodynamics of dogs. Methods - Sixteen mongrel dogs were anesthtized with pentobarbitone 30mg.kg-1 and submitted to volume expansion with Ringer's solution (0.4ml.kg-1.min-1) and mechanical ventilation with room air. In this model, the hemodynamic repercussions of the following drugs and doses were studied: pentobarbitone 5mg,kg-1 - Group 1, control - and the association of pentobarbitone and magnesium sulphate (MS), at the dose of 140 mg.kg-1, injected in 15 minutes, followed by an infusion of 80 mg.kg-1.h-1 - Group 2. The parameters studied were: heart rate, blood pressure, inferior vena cava pressure, cardiac index, systolic index and peripheral resistance index, evaluated at 5 different moments: 15(M1), 30(M2), 60(M3) and 75(M4) minutes after the first supplementary dose of pentobarbitone and 15 minutes (M5) after the second supplementary dose. In group 2, the moments M3, M4, M5 corresponded to 15, 30 and 60 minutes after the priming dose of magnesium sulphate. Results - Group 1 animals exhibited tachycardia since the beginning of the experiment. There was a decrease in the cardiac index, in the systolic index and an increase in the inferior vena cava pressure. group 2 animals also exhibited tachycardia, but heart rate decreased after MS infusion. The blood pressure and the peripheralresitance index decreased. The systolic index increased and the cardiac index decresead only at he end of the experiment. Conclusions - The antiadrenergic effects of Ms could have been responsible for the decrease in heart rate. The vasodilating effects of the magnesium induced the decrease in the peripheral resistance index. The vasodilating effects of the magnesium induced the decrease in the peripheral resistance index. The systolic index increased, showing that myocardial depression did not occur.