Effects of L-carnitine on treatment outcomes of COVID-19 patients hospitalized in intensive care units:A double-blind randomized clinical trial

Objective:To assess the effects of L-carnitine on the outcomes of patients with moderate to severe coronavirus disease 2019(COVID-19)in intensive care unit(ICU).Methods:This double-blind clinical trial was carried out in 2022-2023.64 Patients with COVID-19 were selected from Amiralmomenin and Khansari hospitals in Arak,Iran.They were randomly assigned to the control and the L-carnitine treatment group via block randomization.Venous blood gases,disease severity,and levels of D-dimer,lactate dehydrogenase,ferritin,and C-reactive protein were daily assessed during the seven days of the intervention,and the length of ICU stay,the need for endotracheal intubation,and mortality rate were documented.Results:There were significant differences in length of ICU stay,the need for endotracheal intubation,and levels of D-dimer,lactate dehydrogenase,ferritin,APACHE栻score,and C-reactive protein between the two groups(P<0.05).However,the groups did not significantly differ in mortality rate and venous blood gas indexes(P>0.05).Conclusions:L-carnitine can improve outcomes of patients with COVID-19.Therefore,it can be used as an adjuvant therapy for these patients.

Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study

Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases.

Effective data sampling strategies and boundary condition constraints of physics-informed neural networks for identifying material properties in solid mechanics

Material identification is critical for understanding the relationship between mechanical properties and the associated mechanical functions.However,material identification is a challenging task,especially when the characteristic of the material is highly nonlinear in nature,as is common in biological tissue.In this work,we identify unknown material properties in continuum solid mechanics via physics-informed neural networks(PINNs).To improve the accuracy and efficiency of PINNs,we develop efficient strategies to nonuniformly sample observational data.We also investigate different approaches to enforce Dirichlet-type boundary conditions(BCs)as soft or hard constraints.Finally,we apply the proposed methods to a diverse set of time-dependent and time-independent solid mechanic examples that span linear elastic and hyperelastic material space.The estimated material parameters achieve relative errors of less than 1%.As such,this work is relevant to diverse applications,including optimizing structural integrity and developing novel materials.

A Comparative Study between Landmark Based and Real Time Ultrasound Guided Sub Arachnoid Block

Background: Sub arachnoid block (SAB) performed by traditional landmark palpation technique can be inaccurate. This problem is exacerbated by altered patient anatomy due to obesity and age-related changes. A pre-procedural ultrasound scan of the lumbar spine has been shown to be of benefit in guiding lumbar epidural insertion in obstetric patients. Information on the use of real-time ultrasound (RUS) guided SAB, to date, been limited. This study compared RUS guided SAB to traditional landmark guided technique in patients undergoing spinal anesthesia for different surgical procedures. Methods: This was a prospective, single center, comparative observational study conducted in the department of anesthesiology at our center. 560 patients who underwent spinal anesthesia either by landmark based technique or real-time ultrasound-guided methods. The primary outcome was the first attempt success rate of dural puncture when employing the two methods. Results: Baseline characteristics were similar in the two study groups. The first attempt success rate of dural puncture in landmark guided group was 64.3% compared to 72.6% in the ultrasound guided group. This difference was not statistically significant. The procedure performance time was significantly shorter with landmark palpation compared to use of real-time ultrasound guided method. Conclusion: Use of RUS-guided technique does not significantly improve the first attempt success rate of SAB dural puncture during spinal anesthesia compared to the traditional landmark-guided technique.

Invasive candidiasis in critical care setting, updated recommendations from “Invasive Fungal Infections-Clinical Forum”, Iran

Invasive candidiasis(IC) bears a high risk of morbidity and mortality in the intensive care units(ICU). With the current advances in critical care and the use of widespectrum antibiotics, invasive fungal infections(IFIs) and IC in particular, have turned into a growing concern in the ICU. Further to blood cultures, some auxil-iary laboratory tests and biomarkers are developed to enable an earlier detection of infection, however these test are neither consistently available nor validated in our setting. On the other hand, patients' clinical status and local epidemiology data may justify the empiric antifungal approach using the proper antifungal option. The clinical approach to the management of IC in febrile, non-neutropenic critically ill patients has been defined in available international guidelines; nevertheless such recommendations need to be customized when applied to our local practice. Over the past three years, Iranian experts from intensive care and infectious diseases disciplines have tried to draw a consensus on the management of IFI with a particular focus on IC in the ICU. The established IFI-clinical forum(IFI-CF), comprising the scientific leaders in the field, has recently come up with and updated recommendation on the same(June 2014). The purpose of this review is to put together literature insights and Iranian experts' opinion at the IFI-CF, to propose an updated practical overview on recommended approaches for the management of IC in the ICU.

Effect of High Frequency Oscillatory Ventilation on EVLW and Lung Capillary Permeability of Piglets with Acute Respiratory Distress Syndrome Caused by Pulmonary and Extrapulmonary Insults

The effect of high frequency oscillatory ventilation（HFOV） at early stage on hemodynamic parameters, extravascular lung water（EVLW）, lung capillary permeability, CC16 and s ICAM-1 in piglets with pulmonary or extrapulmonary acute respiratory distress syndrome（ARDS） was explored. Central vein pressure（CVP） and pulse indicator continuous cardiac output（Pi CCO） were monitored in 12 anesthetized and intubated healthy piglets. Pulmonary ARDS（ARDSp） and extrapulmonary ARDS（ARDSexp） models were respectively established by lung lavage of saline solution and intravenous injection of oleic acid. Then the piglets received HFOV for 4 h. EVLW index（EVLWI）, EVLW/intratroracic blood volume（ITBV） and pulmonary vascular permeability index（PVPI） were measured before and after modeling（T0 and T1）, and T2（1 h）, T3（2 h）, T4（3 h） and T5（4 h） after HFOV. CC16 and s ICAM-1 were also detected at T1 and T5. Results showed at T1, T3, T4 and T5, EVLWI was increased more significantly in ARDSp group than in ARDSexp group（P〈0.05）. The EVLWI in ARDSp group was increased at T1（P=0.008）, and sustained continuously within 2 h（P=0.679, P=0.216）, but decreased at T4（P=0.007） and T5（P=0.037）. The EVLWI in ARDSexp group was also increased at T1（P=0.003）, but significantly decreased at T3（P=0.002） and T4（P=0.019）. PVPI was increased after modeling in both two groups（P=0.004, P=0.012）, but there was no significant change within 4 h（T5） under HFOV in ARDSp group, while PVPI showed the increasing trends at first, then decreased in ARDSexp group after HFOV. The changes of EVLW/ITBV were similar to those of PVPI. No significant differences were found in ΔEVLWI（P=0.13）, ΔPVPI（P=0.28） and ΔEVLW/ITBV between the two groups（P=0.63）. The significant decreases in both CC16 and s ICAM-1 were found in both two groups 4 h after HFOV, but there was no significant difference between the two groups. It was concluded that EVLWI and lung capillary permeability were markedly increased in ARDSp and ARDSexp groups. EVLW could be decreased 4 h after the HFOV treatment. HFOV, EVLW/ITBV and PVPI were increased slightly at first, and then decreased in ARDSexp group, while in ARDSp group no significant difference was found after modeling. No significant differences were found in the decreases in EVLW and lung capillary permeability 4 h after HFOV.

Brain-lung crosstalk: Implications for neurocritical care patients

Major pulmonary disorders may occur after brain injuries as ventilator-associated pneumonia, acute respiratory distress syndrome or neurogenic pulmonary edema. They are key points for the management of brain-injured patients because respiratory failure and mechanical ventilation seem to be a risk factor for increased mortality, poor neurological outcome and longer intensive care unit or hospital length of stay. Brain and lung strongly interact via complex pathways from the brain to the lung but also from the lung to the brain. Several hypotheses have been proposed with a particular interest for the recently described "double hit" model. Ventilator setting in brain-injured patients with lung injuries has been poorly studied and intensivists are often fearful to use some parts of protective ventilation in patients with brain injury. This review aims to describe the epidemiology and pathophysiology of lung injuries in brain-injured patients, but also the impact of different modalities of mechanical ventilation on the brain in the context of acute brain injury.

Effect of acetyl-L-carnitine on hypersensitivity in acute recurrent caerulein-induced pancreatitis and microglial activation along the brain’s pain circuitry

BACKGROUND Acute pancreatitis(AP)and recurring AP are serious health care problems causing excruciating pain and potentially lethal outcomes due to sepsis.The validated caerulein-(CAE)induced mouse model of acute/recurring AP produces secondary persistent hypersensitivity and anxiety-like behavioral changes for study.AIM To determine efficacy of acetyl-L-carnitine(ALC)to reduce pain-related behaviors and brain microglial activation along the pain circuitry in CAE-pancreatitis.METHODS Pancreatitis was induced with 6 hly intraperitoneal(i.p.)injections of CAE(50μg/kg),3 d a week for 6 wk in male C57BL/6J mice.Starting in week 4,mice received either vehicle or ALC until experiment’s end.Mechanical hypersensitivity was assessed with von Frey filaments.Heat hypersensitivity was determined with the hotplate test.Anxiety-like behavior was tested in week 6 using elevated plus maze and open field tests.Microglial activation in brain was quantified histologically by immunostaining for ionized calcium-binding adaptor molecule 1(Iba1).RESULTS Mice with CAE-induced pancreatitis had significantly reduced mechanical withdrawal thresholds and heat response latencies,indicating ongoing pain.Treatment with ALC attenuated inflammation-induced hypersensitivity,but hypersensitivity due to abdominal wall injury caused by repeated intraperitoneal injections persisted.Animals with pancreatitis displayed spontaneous anxiety-like behavior in the elevated plus maze compared to controls.Treatment with ALC resulted in increased numbers of rearing activity events,but time spent in“safety”was not changed.After all the abdominal injections,pancreata were translucent if excised at experiment’s end and opaque if excised on the subsequent day,indicative of spontaneous healing.Post mortem histopathological analysis performed on pancreas sections stained with Sirius Red and Fast Green identified wide-spread fibrosis and acinar cell atrophy in sections from mice with CAE-induced pancreatitis that was not rescued by treatment with ALC.Microglial Iba1 immunostaining was significantly increased in hippocampus,thalamus(intralaminar nuclei),hypothalamus,and amygdala of mice with CAE-induced pancreatitis compared to naïve controls but unchanged in the primary somatosensory cortex compared to naïves.CONCLUSION CAE-induced pancreatitis caused increased pain-related behaviors,pancreatic fibrosis,and brain microglial changes.ALC alleviated CAE-induced mechanical and heat hypersensitivity but not abdominal wall injury-induced hypersensitivity caused by the repeated injections.

Supraglottic jet oxygenation and ventilation(SJOV) for resuscitation of injured soldiers and people in war field

Dear Editor,Soldiers or people in battlefield settings are frequently injured with acute trauma, resulting in respiratory depression, hypoxia and associated morbidity and mortality. Traumatic brain injury(TBI) is with as much as 80%–90% of mild to moderate in combat casualties and contributed significantly to morbidity and mortality in battlefield settings. Correction of hypoxia at as capable as possible is expected to reduce or minimize the morbidity/mortality due to acute brain injury. An easy, quick and safe setup to promote oxygenation/ventilation of injured military personnel or peoples by non-medical personnel in battlefield settings immediately after acute injury before transfer to hospital is expected to reduce the morbidity/mortality due to injury mediated respiratory depression.

Does Checklist Implementation Improve Quantity of Data Transfer: An Observation in Postanesthesia Care Unit (PACU)

Background: Omission of patient information in perioperative communication is closely linked to adverse events. Use of checklists to standardize the handoff in the post anesthesia care unit (PACU) has been shown to effectively reduce medical errors. Objective: Our study investigates the use of a checklist to improve quantity of data transfer during handoffs in the PACU. Design: A cross-sectional observational study. Setting: PACU at Memorial Sloan Kettering Cancer Center (MSKCC);June 13, 2016 through July 15, 2016. Patients, other participants: We observed the handoff reports between the nurses, PACU midlevel providers, anesthesia staff, and surgical staff. Intervention: A physical checklist was provided to all anesthesia staff and recommended to adhere to the list at all observed PACU handoffs. Main outcome measure: Quantity of reported handoff items during 60 pre- and 60 post-implementation of a checklist. Results: Composite value from both surgical and anesthesia reports showed an increase in the mean report of 8.7 items from pre-implementation period to 10.9 post-implementation. Given that surgical staff reported the mean of 5.9 items pre-implementation and 5.5 items post-implementation without intervention, improvements in anesthesia staff report with intervention improved the overall handoff data transfer. Conclusions: Using a physical 12-item checklist for PACU handoff increased overall data transfer.

Intraoperative glycemic control procedures and the use of an artificial pancreas

Strict intraoperative glycemic control can significantly decrease the incidence of postoperative infection; however, anesthesiologists must carefully control blood glucose levels as well as properly manage the respiratory and cardiovascular systems. However, standard blood glucose measurement systems and insulin dosing algorithms, which are necessary for achieving strict glycemic control, have not yet been developed. An artificial pancreas (STG-22TM; Nikkiso Co., Tokyo, Japan) is considered a highly accurate blood glucose monitoring system capable of closed-loop control of blood glucose. The device has, however, many problems to be addressed since it is a large and expensive system with little versatility, and it requires a large amount of blood to be collected. Therefore, the development of less invasive and inexpensive systems with future technological progress is greatly anticipated.

Comparative effect of intrathecal meperidine,tramadol,magnesium sulfate,and dexmedetomidine on preventing post-spinal anesthesia shivering and adverse events in hip fracture repair patients:A randomized clinical trial

Objective:To compare effect of intrathecal meperidine,tramadol,magnesium sulfate,and dexmedetomidine on the prevention of post-spinal anesthesia shivering and adverse events in hip fracture repair patients.Methods:In a randomized,double-blind trial,132 patients with American Society of Anesthesiology(ASA)ⅠandⅡspinal anesthesia who needed hip fracture surgery were enrolled.Patients were stratified into 4 intervention groups based on a randomized block pattern:meperidine,tramadol,magnesium sulfate,and dexmedetomidine.Hemodynamic parameters including blood pressure,heart rate,and oxygen saturation,as well as the severity of shivering,core body temperature,Ramsay sedation score,adverse events,meperidine consumption were recorded and compared.Results:There was no statistically significant difference in the normal hemodynamic parameters,temperature,duration of surgery,meperidine consumption,and adverse events such as dizziness,hypotension,nausea,and bradycardia among groups(P>0.05).Compared to other groups,severity of shivering was the lower in the dexmedetomidine group 6 and 8 h after surgery.The Ramsay sedation scores were higher in the dexmedetomidine and meperidine groups 4 h after surgery(P=0.020).Conclusion:Dexmedetomidine acts better than the other three adjuvants in reducing complications such as shivering.Overall,these four adjuvants are helpful to prevent postoperative shivering and could be put forward as promising local anesthetics in spinal anesthesia,based on anesthesiologists’discretion and patients’general conditions.Clinical registration:The study was approved by the Research and Ethics Committee at the Valiasr Hospital(Arak,Iran)with the clinical trial code of IRCT20141209020258N153.

Electrical stimulation of cortical neurons promotes oligodendrocyte development and remyelination in the injured spinal cord

Background and early studies： Endogenous tri-potential neural stem cells （NSCs） exist in the adult mammalian central nervous system （CNS）. In the spinal cord, NSCs distribute throughout the entire cord, but exist predominately in white matter tracts. The phenotypic fate of these cells in white matter is glial, largely oligodendrocyte, but not neuronal.

The Effects of Glucose Load on Catabolism during Remifentanil-Based Anesthesia in Patients with Diabetes Mellitus: A Prospective Randomized Trial

Background: General anesthesia using remifentanil may suppress the unwanted metabolic changes caused by surgical stress including hyperglycemia and ketogenesis. Surgery-related changes in catabolism can be attenuated with low-dose glucose load, without causing hyperglycemia. However, the impact of glucose load in diabetic patients during surgery is unknown. In this study, we investigated the effect of glucose load on catabolism during remifentanil-based anesthesia in patients with diabetes mellitus. Methods: Twenty-nine patients with diabetes mellitus undergoing elective surgery were randomly assigned to receive a glucose load (1.5 mg/kg/min) or not. Plasma levels of glucose, insulin, cortisol, dopamine, adrenaline, noradrenaline, acetoacetic acid, free fatty acid, ketone bodies, 3-hydroxybutyric acid, and 3-methylhistidine/creatinine, a marker of protein catabolism were measured at the start of surgery and 3 h after the start of surgery. Results: Glucose and insulin levels were significantly higher in patients who received a glucose load than in those who did not. Cortisol levels decreased at 3 h after the start of surgery in both groups whereas the levels of catecholamines were unchanged. Acetoacetic acid and total ketone body levels were significantly lower in patients given a glucose load than in those who were not 3 h after the start of surgery. The difference in the 3 methylhistidine/creatinine ratio between the two groups was not significant. Conclusions: The infusion of glucose suppressed lipid catabolism in diabetic patients under remifentanil-based anesthesia during surgery. Our study also suggests that in patients with diabetes mellitus, protein sparing is inhibited by remifentanil-based anesthesia, regardless of the glucose load. Trial registration: the University Hospital Medical Information Network identifier: UMIN000010914.

Intraoperative Gastric Tube Intubation: A Summary of Case Studies and Review of the Literature

Study Objective: Establish complications and risk factors that are associated with blind tube insertion, evaluate the validity of correct placement verification methods, establish the rationales supporting its employment by anesthesia providers, and describe various deployment facilitators described in current literature. Measurements: An exhaustive literature review of the databases Medline, CINAHL, Cochrane Collaboration, Scopus, and Google Scholar was performed applying the search terms “gastric tube”, “complications”, “decompression”, “blind insertion”, “perioperative”, “intraoperative” in various order sequences. A five-year limit was applied to limit the number and timeliness of articles selected. Main Results: Patients are exposed to potentially serious morbidity and mortality from blindly inserted gastric tubes. Risk factors associated with malposition include blind insertion, the presence of endotracheal tubes, altered sensorium, and previous tube misplacements. Pulmonary aspiration risk prevention remains the only indication for anesthesia-related intraoperative use. There are no singularly effective tools that predict or verify the proper placement of blindly inserted gastric tubes. Current placement facilitation techniques are perpetuated through anecdotal experience and technique variability warrants further study. Conclusion: In the absence of aspiration risk factors or the need for surgical decompression in ASA classification I & II patients, a moratorium should be instituted on the elective use of gastric tubes.

Effects of Glucose Load on Catabolism during Propofol-Based Anesthesia with Remifentanil in Patients with Diabetes Mellitus: A Prospective Randomized Trial

Background: Perioperative exacerbation of hyperglycemia and insulin resistance is associated with increased complications in patients with diabetes mellitus. We recently reported that glucose load during anesthesia with sevoflurane suppressed lipid catabolism in diabetic patients. In contrast to inhaled anesthetics, propofol solution contains triglycerides, which can be an energy source during surgery. However, the clinical relevance of glucose load under propofol-based anesthesia in diabetic patients is unknown. Therefore, we investigated the effect of intraoperative glucose load on catabolism during propofol-based anesthesia in patients with diabetes mellitus. Methods: Twenty-three patients with diabetes mellitus undergoing elective surgery with propofol-remifentanil-based anesthesia were randomly assigned to receive a glucose load (1.5 mg/kg/ min) or not. Plasma levels of glucose, insulin, cortisol, catecholamines, acetoacetic acid, free fatty acids, ketone bodies, 3-hydroxybutyric acid, and 3-methylhistidine/creatinine, used as a marker for protein catabolism, were measured at the start of surgery and 3 h later. Results: Glucose and insulin levels were significantly higher in patients who received a glucose load than in those who did not. Nonetheless, the levels of cortisol and catecholamines were unchanged during surgery. Similarly, the difference in the levels of markers for lipid as well as protein catabolism was not significant between the groups at 3 h after the start of surgery. Conclusions: Changes in lipid as well as protein catabolism were not altered by glucose load in diabetic patients under propofol-based anesthesia with remifentanil. Our study suggested that continuous infusion of propofol at a clinical dose is sufficient to reduce the requirement for glucose infusion during surgery in patients with diabetes.

Heart‘omicsin’AGEing (HOMAGE):design,research objectives and characteristics of the common database

Heart failure is common in older people and its prevalence is increasing.The Heart ＇omics＇ in AGEing（HOMAGE） project aims to provide a biomarker approach that will improve the early diagnosis of heart failure.A large clinical database,based on（1） prospective population studies or（2） cross-sectional,prospective studies or randomized controlled trials（RCTs） of patients at risk for or with overt cardiovascular disease will be constructed to determine most promising ＇omics＇-based biomarkers to identify the risk of developing heart failure and/or comorbidities.Population studies,patient cohorts and RCTs are eligible for inclusion in the common database,if they received ethical approval to obtain and share data and have baseline information on cardiovascular risk factors.Currently,the HOMAGE database includes 43,065 subjects,from 20 studies in eight European countries,including healthy subjects from three population studies in France,Belgium and Italy（n = 7,124）,patients with heart failure（n = 4,312） from four cohorts in the UK,Spain and Switzerland and patients at high risk for cardiovascular disease（n = 31,629） in 13 cohorts.It is anticipated that more partners will join the consortium and enlarge the pooled data.This large merged database will be a useful resource with which to identify candidate biomarkers that play a role in the mechanism underlying the onset and progression of heart failure.

Remifentanil Has Sufficient Hypnotic and Amnesic Effect for Induction of Anesthesia by Itself

With a small-dose remifentanil, some patients showed no reaction and did not remember it postoperatively. We, therefore, hypothesized that remifentanil may decrease the level of consciousness and/or exhibit amnesic effect when stimulations are avoided. Thirty-patients were divided into two groups: non-stimulation group and stimulation group. Anesthesia was induced with 1 micro-g·kg?1·min?1 of remifentanil using no additional hypnotic agent. In the non-stimulation group, patients were left free from any stimulation except non-invasive blood pressure monitoring. In the stimulation group, patients were asked to follow verbal commands. The level of consciousness was evaluated with electroencephalogram and BIS-value derived from it. In the non-stimulation group, all patients reached the decreased level of consciousness in 5 minutes. In the stimulation group, however, 14 patients were judged to be still conscious. 10 patients could open their mouth at the 5th minute, but 9 of these 10 patients did not remember it postoperatively. In conclusion, remifentanil, with no additional anesthetics, exhibited hypnotic and amnesic effects when stimulations were kept minimal.

Comparison of Acoustic Respiration Rate, Impedance Pneumography and Capnometry Monitors for Respiration Rate Accuracy and Apnea Detection during GI Endoscopy Anesthesia

Study Objective: To assess the accuracy of respiration rate measurements and the ability to detect apnea by capnometry, impedance pneumography and a new method, acoustic respiration rate monitoring, in anesthetized patients undergoing gastrointestinal endoscopy procedures. Design: Prospective observational study. Setting: Endoscopy procedures laboratory. Patients: 98 patients scheduled for upper gastrointestinal endoscopy with propofol-based anesthesia. Interventions: Patients were monitored for respiration rate with acoustic respiration rate monitoring, capnometry and impedance pneumography and values were compared to the manual counting of breaths by observation of chest wall movements. Additionally, when any respiration rate monitor indicated a cessation of breathing for 30 seconds or greater, the presumed apnea was confirmed by direct observation of the patient for absence of chest wall movements. Measurements and Main Results: Bias and precision for respiration rate measurement was 0 ± 1.0 bpm for acoustic monitoring, 4.8 ± 15.1 bpm for capnometry and 0.4 ± 5.9 bpm for impedance pneumography. Sensitivity and specificity for detection of apnea was 73% and 93% for acoustic monitoring, 73% and 12% for capnometry and 45% and 93% for impedance pneumography. Conclusions: Acoustic respiration rate monitoring was found to be accurate for assessment of respiration rate and to have similar or better sensitivity and specificity for detection of apnea compared to capnometry and impedance pneumography in the setting of upper GI endoscopy.

Perioperative care and cancer recurrence: Is there a connection?

Cancer is the second most common cause of death in the United States. Metastatic disease is a more important cause of cancer-related death relative to primary tumor progression. Surgical excision is the primary treatment for most malignant tumors. However, surgery itself can inhibit important host defenses and promote the development of metastases. An altered balance between the metastatic potential of the tumor and the anti-metastatic host defenses, including cellmediated immunity and natural killer cell function, is a plausible mechanism of increased cancer metastasis. This article reviews the increasingly recognized concept of anesthetic technique along with perioperative factors and their potential to affect long-term outcome after cancer surgery. The potential effect of intravenous anesthetics, volatile agents, local anesthetic drugs, opiates, and non-steroidal anti-inflammatory drugs are reviewed along with recent literature and ongoing clinical trials in this area. Regional anesthesia is increasingly emerging as a safer option with less cancer recurrence potential as compared to general anesthesia. Blood transfusion, pain, stress, use of beta-blockers, and hypothermia are other potentially important perioperative factors to consider.