Benefits and harms of perioperative high fraction inspired oxygen for surgical site infection prevention: a protocol for a systematic review and meta-analysis of individual patient data of randomised controlled trials.

INTRODUCTION: The use of high fraction of inspired oxygen (FiO2) intraoperatively for the prevention of surgical site infection (SSI) remains controversial. Promising results of early randomised controlled trials (RCT) have been replicated with varying success and subsequent meta-analysis are equivocal. Recent advancements in perioperative care, including the increased use of laparoscopic surgery and pneumoperitoneum and shifts in fluid and temperature management, can affect peripheral oxygen delivery and may explain the inconsistency in reproducibility. However, the published data provides insufficient detail on the participant level to test these hypotheses. The purpose of this individual participant data meta-analysis is to assess the described benefits and harms of intraoperative high FiO2compared with regular (0.21-0.40) FiO2 and its potential effect modifiers. METHODS AND ANALYSIS: Two reviewers will search medical databases and online trial registries, including MEDLINE, Embase, CENTRAL, CINAHL, ClinicalTrials.gov and WHO regional databases, for randomised and quasi-RCT comparing the effect of intraoperative high FiO2 (0.60-1.00) to regular FiO2 (0.21-0.40) on SSI within 90 days after surgery in adult patients. Secondary outcome will be all-cause mortality within the longest available follow-up. Investigators of the identified trials will be invited to collaborate. Data will be analysed with the one-step approach using the generalised linear mixed model framework and the statistical model appropriate for the type of outcome being analysed (logistic and cox regression, respectively), with a random treatment effect term to account for the clustering of patients within studies. The bias will be assessed using the Cochrane risk-of-bias tool for randomised trials V.2 and the certainty of evidence using Grading of Recommendations, Assessment, Development and Evaluation methodology. Prespecified subgroup analyses include use of mechanical ventilation, nitrous oxide, preoperative antibiotic prophylaxis, temperature (<35°C), fluid supplementation (<15 mL/kg/hour) and procedure duration (>2.5 hour). ETHICS AND DISSEMINATION: Ethics approval is not required. Investigators will deidentify individual participant data before it is shared. The results will be submitted to a peer-review journal. PROSPERO REGISTRATION NUMBER: CRD42018090261.

Optimization of Endotracheal Tube Cuff Pressure by Monitoring CO2 Levels in the Subglottic Space in Mechanically Ventilated Patients: A Randomized Controlled Trial.

BACKGROUND: Many of the complications of mechanical ventilation are related to inappropriate endotracheal tube (ETT) cuff pressure. The aim of the current study was to evaluate the effectiveness of automatic cuff pressure closed-loop control in patients under prolonged intubation, where presence of carbon dioxide (CO2) in the subglottic space is used as an indicator for leaks. The primary outcome of the study is leakage around the cuff quantified using the area under the curve (AUC) of CO2 leakage over time. METHODS: This was a multicenter, prospective, randomized controlled, noninferiority trial including intensive care unit patients. All patients were intubated with the AnapnoGuard ETT, which has an extra lumen used to monitor CO2 levels in the subglottic space.The study group was connected to the AnapnoGuard system operating with cuff control adjusted automatically based on subglottic CO2 (automatic group). The control group was connected to the AnapnoGuard system, while cuff pressure was managed manually using a manometer 3 times/d (manual group). The system recorded around cuff CO2 leakage in both groups. RESULTS: Seventy-two patients were recruited and 64 included in the final analysis. The mean hourly around cuff CO2 leak (mm Hg AUC/h) was 0.22 ± 0.32 in the manual group and 0.09 ± 0.04 in the automatic group (P = .01) where the lower bound of the 1-sided 95% confidence interval was 0.05, demonstrating noninferiority (>-0.033). Additionally, the 2-sided 95% confidence interval was 0.010 to 0.196, showing superiority (>0.0) as well. Significant CO2 leakage (CO2 >2 mm Hg) was 0.027 ± 0.057 (mm Hg AUC/h) in the automatic group versus 0.296 ± 0.784 (mm Hg AUC/h) in the manual group (P = .025). In addition, cuff pressures were in the predefined safety range 97.6% of the time in the automatic group compared to 48.2% in the automatic group (P < .001). CONCLUSIONS: This study shows that the automatic cuff pressure group is not only noninferior but also superior compared to the manual cuff pressure group. Thus, the use of automatic cuff pressure control based on subglottic measurements of CO2 levels is an effective method for ETT cuff pressure optimization. The method is safe and can be easily utilized with any intubated patient.

Basic Features and Clinical Applicability of 'Preliminary Universal Surgical Invasiveness Score' (pUSIS): A Multi-Centre Pilot Study.

OBJECTIVE: There is still a lack of a universally applicable and comprehensive scoring system for documenting the invasiveness of surgical procedures. The proposed preliminary 'Universal Surgical Invasiveness Score' (pUSIS) is intended to fill this gap. METHODS: We used the recently developed pUSIS to obtain values from 8 types of surgery and 80 individual interventions. The results were analysed using descriptive statistical methods. The degree of difficulty on a scale from 0 (very easy) to 10 (extremely difficult) and time expenditures for assessing pUSIS were documented. RESULTS: Individual pUSIS values ranged from 8 in a laparoscopic cholecystectomy case to 36 in a total hip replacement case. The lowest median pUSIS value of 11.5 was found for laparoscopic cholecystectomy and the highest value of 24.5 was found for open thoracic surgery. The correlation between pUSIS values and the duration of surgery resulted in a tight linear regression (R2=0.6419). The lowest mean (±SD) difficulty level to obtain pUSIS values was 1.6±0.6 for sleeve gastrectomy and the highest one was 2.9±0.6 for knee replacement. The duration to finalise the calculations was 4.1±1.1 min for video-assisted thoracoscopy (VATS) and 9.4±1.3 min for sleeve gastrectomy. CONCLUSION: We concluded that pUSIS has the potential to be a useful, simply obtainable and universal assessment tool for quantification of the magnitude and invasiveness of individual surgical operations and can serve as a means to quantify surgical interventions for outcome research and evaluate surgical performance.

Management of the hopelessly ill patient: to stop or not to start?

The paper discusses the subject of futile treatment in the case of a hopelessly ill patient. The topic has many facets, among them the ethical precepts of preventing futile treatment, but also the economic and logistic impact of treating patients who do not have a fair chance of benefitting from managing their medical condition. A 75-year old patient, suffering from an advanced stage of Alzheimer's disease and a clinical picture of acute surgical abdomen, is presented and two approaches are discussed. The first scenario is the aggressive management, including immediate laparotomy and admission to an intensive care unit, a solution without a fair chance of saving the patient's life. The most favorable, but theoretical, output in this case would be the patient's return to his previous mental condition, without any connection with the reality and surroundings and in permanent need for help, supervision and assistance. The second option is letting the patient die in dignity, alleviating pain and surrounded by family. The role of the primary care physician and family is discussed and some ethical principles are presented in order to emphasize the importance of preventing futile treatment in a case of a terminally ill patient.

Detection of endobronchial intubation by monitoring the CO2 level above the endotracheal cuff.

Early detection of accidental endobronchial intubation (EBI) is still an unsolved problem in anesthesia and critical care daily practice. The aim of this study was to evaluate the ability of monitoring above cuff CO2 to detect EBI (the working hypothesis was that the origin of CO2 is from the unventilated, but still perfused, lung). Six goats were intubated under general anesthesia and the ETT positioning was verified by a flexible bronchoscope. The AnapnoGuard system, already successfully used to detect air leak around the ETT cuff, was used for continuous monitoring of above-the-cuff CO2 level. When the ETT distal tip was located in the trachea, with an average cuff pressure of 15 mmHg, absence of CO2 above the cuff was observed. The ETT was then deliberately advanced into one of the main bronchi under flexible bronchoscopic vision. In all six cases the immediate presence of CO2 above the cuff was identified. Further automatic inflation of the cuff, up to a level of 27 mmHg, did not affect the above-the-cuff measured CO2 level. Withdrawal of the ETT and repositioning of its distal tip in mid-trachea caused the disappearance of CO2 above the cuff in a maximum of 3 min, confirming the absence of air leak and the correct positioning of the ETT. Our results suggest that measurement of the above-the-cuff CO2 level could offer a reliable, on-line solution for early identification of accidental EBI. Further studies are planned to validate the efficacy of the method in a clinical setup.

Factors encouraging and inhibiting organ donation in Israel: the public view and the contribution of legislation and public policy.

Although transplantation surgeries are relatively successful and save the lives of many, only few are willing to donate organs. In order to better understand the reasons for donation or refusing donation and their implications on and influence by public policy, we conducted a survey examining public views on this issue in Israel. Between January and June 2010, an anonymous questionnaire based on published literature was distributed among random and selected parts of Israeli society and included organ recipients, organ donors, soldiers, university and high school students, and the general population. The analysis of 799 questionnaires revealed that, although 74.7 percent have not signed a donor card, 60.8 percent of participants consider doing so. Additionally, 54.3 percent of respondents objected to giving or receiving compensation for donation, and, if at all, priority in transplantation care is the most desired form of such compensation. The health status of the donor and knowing that donation saves lives or that there exists a shortage of organs for transplantation are the two factors most affecting motivation to donate. Lack of information, relatives' views on donation, and type of organ involved in donation are factors most inhibiting donation. Willingness to donate is significantly affected by the proximity of the recipient to the donor. With regard to most organs, their contribution to one's sense of "self" and its symbolic role strongly affects motivation to donate, except for donation to relatives. Compensation for organ donation has little effect on motivation to donate during life and after death. Our findings suggest new ways to construct a more effective public policy on this issue.

Do waking salivary cortisol levels correlate with anesthesiologist's job involvement?

Anesthetists' work carries great responsibility and can be very stressful. Cognitive appraisal plays a central role in stress responses; however, little is known about the relationship between stress appraisal and biological markers of stress, particularly among anesthesiologists. Stress response may be associated with increased levels of systemic cortisol, which can be conveniently measured in saliva and used as a marker for the extent of stress. The objective of this study was to examine the correlation between work-related cognitive variables and waking salivary cortisol, a possible stress marker, in anesthesiologists. Thirty-eight anesthesiologists were assessed for work-related thought intrusions and perceived "mental distance" between themselves and their work, using the pictorial representation of illness self-measure (PRISM), and underwent an implicit association test reflecting implicit job-stress associations. Salivary cortisol was measured twice upon awakening and an hour later, in saliva samples, using a kit based on chemoluminescence competition assay. Only implicit job-stress associations were correlated with waking cortisol (r = 0.35, p < 0.05). Furthermore, high implicit job-stress was related to elevated cortisol only among anesthesiologists reporting large "mental distance" from work, which may represent limited job involvement related to burnout. Anesthesiologists with a low degree of job involvement who have high implicit job-stress associations have higher levels of waking salivary cortisol. Further studies are necessary to assess the impact of stress management techniques on anesthesiologists' personal and professional behavior as well as on the quality of medical care.

Endotracheal tube cuff--small important part of a big issue.

Many of the complications related to prolonged ventilation are related to inappropriate handling of endotracheal tube (ETT) cuff. This article reviews the possible complications associated with the ETT cuff, and the landmark development made in that field. The article challenges the present paradigm of cuff use and reviews the current clinical practice in that area.

Professional stress in anesthesiology: a review.

Anesthesiology is a stressful medical profession. While anesthesia in particular has become safer for the patient in the last decades, anesthesiology as a profession represents a medical field in which the professionals are permanently tense. The various reasons for this situation include the fact that anesthesiology is a team profession that requires perfect cooperation with other specialists. It also entails great responsibility for the patient's life, the daily use of "blind" invasive techniques, and last but not least the production pressure that characterizes the activity in the operating room. There are various methods to quantify professional stress and this article emphasizes the place of measurement of salivary cortisol in order to identify those stressful moments that are part of the anesthesiologist's routine activity, in addition to those individuals who are more prone to develop negative aspects of stress. It seems that there is a strong correlation between the high level of salivary cortisol and stressful events during patient management and also a correlation between this level and a high score of implicit job-stress. This reality created the need to look for remedies; some authors recommend a long list of measures to be taken in order to prevent or reduce the magnitude of professional stress. This list includes a continuous self-care attitude, consisting of having a balanced professional and personal life; adequate sleep; avoiding drugs, obesity, and "workaholic" behavior; as well as better use of leisure. Finally, more studies are needed to find out which preventive means may potentially reduce the risk of professional stress among anesthesiologists.

The Eldicus prospective, observational study of triage decision making in European intensive care units. Part II: intensive care benefit for the elderly.

RATIONALE: Life and death triage decisions are made daily by intensive care unit physicians. Admission to an intensive care unit is denied when intensive care unit resources are constrained, especially for the elderly. OBJECTIVE: To determine the effect of intensive care unit triage decisions on mortality and intensive care unit benefit, specifically for elderly patients. DESIGN: Prospective, observational study of triage decisions from September 2003 until March 2005. SETTING: Eleven intensive care units in seven European countries. PATIENTS: All patients >18 yrs with an explicit request for intensive care unit admission. INTERVENTIONS: Admission or rejection to intensive care unit. MEASUREMENTS AND MAIN RESULTS: Demographic, clinical, hospital, physiologic variables, and 28-day mortality were obtained on consecutive patients. There were 8,472 triages in 6,796 patients, 5,602 (82%) were accepted to the intensive care unit, 1,194 (18%) rejected; 3,795 (49%) were ≥ 65 yrs. Refusal rate increased with increasing patient age (18-44: 11%; 45-64: 15%; 65-74: 18%; 75-84: 23%; >84: 36%). Mortality was higher for older patients (18-44: 11%; 45-64: 21%; 65-74: 29%; 75-84: 37%; >84: 48%). Differences between mortalities of accepted vs. rejected patients, however, were greatest for older patients (18-44: 10.2% vs. 12.5%; 45-64: 21.2% vs. 22.3%; 65-74: 27.9% vs. 34.6%; 75-84: 35.5% vs. 40.4%; >84: 41.5% vs. 58.5%). Logistic regression showed a greater mortality reduction for accepted vs. rejected patients corrected for disease severity for elderly patients (age >65 [odds ratio 0.65, 95% confidence interval 0.55-0.78, p < .0001]) than younger patients (age <65 [odds ratio 0.74, 95% confidence interval 0.57-0.97, p = .01]). CONCLUSIONS: Despite the fact that elderly patients have more intensive care unit rejections than younger patients and have a higher mortality when admitted, the mortality benefit appears greater for the elderly. Physicians should consider changing their intensive care unit triage practices for the elderly.

The Eldicus prospective, observational study of triage decision making in European intensive care units: part I--European Intensive Care Admission Triage Scores.

OBJECTIVE: Life and death triage decisions are made daily by intensive care unit physicians. Scoring systems have been developed for prognosticating intensive care unit mortality but none for intensive care unit triage. The objective of this study was to develop an intensive care unit triage decision rule based on 28-day mortality rates of admitted and refused patients. DESIGN: Prospective, observational study of triage decisions from September 2003 until March 2005. SETTING: Eleven intensive care units in seven European countries. PATIENTS: All patients >18 yrs with a request for intensive care unit admission. INTERVENTIONS: Admission or rejection to an intensive care unit. MEASUREMENTS AND MAIN RESULTS: Clinical, laboratory, and physiological variables and data from severity scores were collected. Separate scores for accepted and rejected patients with 28-day mortality end point were built. Values for variables were grouped into categories determined by the locally weighted least squares graphical method applied to the logit of the mortality and by univariate logistic regressions for reducing candidates for the score. Multivariate logistic regression was used to construct the final score. Cutoff values for 99.5% specificity were determined. Of 6796 patients, 5602 were admitted and 1194 rejected. The initial refusal score included age, diagnosis, systolic blood pressure, pulse, respirations, creatinine, bilirubin, PaO2, bicarbonate, albumin, use of vasopressors, Glasgow Coma Scale score, Karnofsky Scale, operative status and chronic disorder, and the initial refusal receiver operating characteristics were area under the curve 0.77 (95% confidence interval 0.76-0.79). The final triage score included age, diagnosis, creatinine, white blood cells, platelets, albumin, use of vasopressors, Glasgow Coma Scale score, Karnofsky Scale, operative status and chronic disorder, and the final score receiver operating characteristics were area under the curve 0.83 (95% confidence interval 0.80-0.86). Patients with initial refusal scores >173.5 or final triage scores = 0 should be rejected. CONCLUSIONS: The initial refusal score and final triage score provide objective data for rejecting patients that will die even if admitted to the intensive care unit and survive if refused intensive care unit admission.

Implications of ICU triage decisions on patient mortality: a cost-effectiveness analysis.

INTRODUCTION: Intensive care is generally regarded as expensive, and as a result beds are limited. This has raised serious questions about rationing when there are insufficient beds for all those referred. However, the evidence for the cost effectiveness of intensive care is weak and the work that does exist usually assumes that those who are not admitted do not survive, which is not always the case. Randomised studies of the effectiveness of intensive care are difficult to justify on ethical grounds; therefore, this observational study examined the cost effectiveness of ICU admission by comparing patients who were accepted into ICU after ICU triage to those who were not accepted, while attempting to adjust such comparison for confounding factors. METHODS: This multi-centre observational cohort study involved 11 hospitals in 7 EU countries and was designed to assess the cost effectiveness of admission to intensive care after ICU triage. A total of 7,659 consecutive patients referred to the intensive care unit (ICU) were divided into those accepted for admission and those not accepted. The two groups were compared in terms of cost and mortality using multilevel regression models to account for differences across centres, and after adjusting for age, Karnofsky score and indication for ICU admission. The analyses were also stratified by categories of Simplified Acute Physiology Score (SAPS) II predicted mortality (< 5%, 5% to 40% and >40%). Cost effectiveness was evaluated as cost per life saved and cost per life-year saved. RESULTS: Admission to ICU produced a relative reduction in mortality risk, expressed as odds ratio, of 0.70 (0.52 to 0.94) at 28 days. When stratified by predicted mortality, the odds ratio was 1.49 (0.79 to 2.81), 0.7 (0.51 to 0.97) and 0.55 (0.37 to 0.83) for <5%, 5% to 40% and >40% predicted mortality, respectively. Average cost per life saved for all patients was $103,771 (€82,358) and cost per life-year saved was $7,065 (€5,607). These figures decreased substantially for patients with predicted mortality higher than 40%, $60,046 (€47,656) and $4,088 (€3,244), respectively. Results were very similar when considering three-month mortality. Sensitivity analyses performed to assess the robustness of the results provided findings similar to the main analyses. CONCLUSIONS: Not only does ICU appear to produce an improvement in survival, but the cost per life saved falls for patients with greater severity of illness. This suggests that intensive care is similarly cost effective to other therapies that are generally regarded as essential.

Tracheal pressure and endotracheal tube obstruction can be detected by continuous cuff pressure monitoring: in vitro pilot study.

PURPOSE: To evaluate whether the degree of endotracheal tube (ETT) obstruction can be predicted by changes of ETT cuff pressure (P (c)) as a function of peak inspiratory pressure. METHODS: The study was conducted in three phases: phase I evaluated the correlation between peak tracheal pressure (P (tr)) and P (c); phase II evaluated the relation between P (c) versus ventilator pressure (P (v)) and ETT obstruction (range of obstruction 0-58%). In phase III the analytical model developed in phase II was used to predict the degree of obstruction of five ETTs removed from intensive care unit (ICU) patients. All measurements were conducted on a tracheal-lung simulator. RESULTS: In phases I and II it was found that P (c) correlates significantly with P (tr). The gradient (dP (c)/dP (v)) reflects the degree of ETT obstruction according to the formula: obstruction (%) = -553 x (dP (c)/dP (v))(2) + 672.5 x (dP (c)/dP (v)) - 142.81. Using this formula, the degree of obstruction of the ETTs could be predicted in ICU patients during controlled mechanical ventilation (r (2) = 0.98, p < 0.001). CONCLUSIONS: This study proposes a new method to predict the degree of ETT obstruction based on differences between P (c) and P (v). The method was proved accurate on simulator, and further studies are needed on intubated patients.

Ventilator-associated pneumonia: current status and future recommendations.

OBJECTIVE: Ventilator-associated pneumonia (VAP) is a common hazardous complication in ICU patients. The aim of the current review is to give an update on the current status and future recommendations for VAP prevention. METHODS: This article gives an updated review of the current literature on VAP. The first part briefly reviews pathogenesis and epidemiology while the second includes an in-depth review of evidence-based practice guidelines (EBPG) and new technologies developed for prevention of VAP. RESULTS: VAP remains a frequent and costly complication of critical illness with a pooled relative risk of 9-27% and mortality of 25-50%. Strikingly, VAP adds an estimated cost of more than $40,000 to a typical hospital admission. An important aetiological mechanism of VAP is gross or micro-aspiration of oropharyngeal organisms around the cuff of the endotracheal tube (ETT) into the distal bronchi. Prevention of VAP is preferable. Preventative measures can be divided into two main groups: the implemen- tation of EBPGs and use of device-based technologies. EBPGs have been authored jointly by the American Thoracic Society and the Infectious Diseases Society of America. The Canadian Critical Care Trials group also published VAP Guidelines in 2008. Their recommendations are detailed in this review. The current device-based technologies include drainage of subglottic secretions, silver coated ETTs aiming to influence the internal bio-layer of the ETT, better sealing of the lower airways with ultrathin cuffs and loops for optimal cuff pressure control. CONCLUSIONS: EBPG consensus includes: elevation of the head of the bed, use of daily "sedation vacations" and decontamination of the oropharynx. Technological solutions should aim to use the most comprehensive combination of subglottic suction of secretions, optimization of ETT cuff pressure and ultrathin cuffs. VAP is a type of hospital-acquired pneumonia that develops more than 48 h after endotracheal intubation. Its incidence is estimated to be 9-27%, with a mortality of 25-50% [Am J Respir Crit Care Med 171:388-416 (2005), Am J Med 85:499-506 (1988), Chest 122:2115-2121 (2002), Intensive Care Med 35:9-29 (2009)]. The most important target in VAP handling is its prevention. The aim of this article is to review the pathogenesis, epidemiology and the different strategies/technologies for prevention of VAP.

[Organ transplantation in Israel of 2007--reality and vision].

The situation of organ transplantation in Israel has currently reached a crossroad. The number of patients on the waiting list increases from one year to another, but the availability of organs remains, more or less, the same as in the last decade. As a result, the medical condition of the patients on the waiting list deteriorates and each year some 7% of these patients died before an organ could be procured for saving their lives. Since 1994 the organ transplantation system in Israel is nationally controlled by the Israel Transplant Center (ITC) which employs transplantation teams (a physician and at least one registered nurse) acting in each general hospital. ITC and the teams proceed in the direction of identification of potential donors after brain death, hemodynamic stabilization, talks with the patient's family aiming to obtain acceptance for donating the deceased person's organs and the logistic aspects of organ harvesting and transplantation. This review presents the up to date parameters of organ transplantation in Israel and compares this information with some data from other countries. The data from last year placed Israel on the lower part of the list of developed countries regarding the availability of organs for transplantation: 9 donors per million inhabitants (in comparison to 35 in Spain or 25 in the USA). Furthermore, a lower percentage of the Israeli adult population (9.4% as per March 2008) signed a donor card, thereby expressing the intention to donate organs after death. Finally, some ideas for improving the situation of organ donation in this country are proposed, among them a continuous campaign for increasing population awareness regarding organ donation, the use of non-heart beating donor organs, the use of expanded criteria for donated organs, development of a system of pair exchange in case of immunologic incompatibility between the donor and the recipient or the use of solutions and machines for organ perfusion in order to increase the viability time of the harvested organ.

Acoustic monitoring of double-lumen ventilated lungs for the detection of selective unilateral lung ventilation.

One-lung intubation (OLI) is among the most common complications of endotracheal intubation. None of the monitoring tools now available has proved effective for its early detection. In this study we investigated the efficacy of acoustic analysis for the detection of OLI. We collected lung sounds from 11 patients undergoing thoracic surgery requiring the placement of a double-lumen tube. Recordings of separate lung ventilation were performed after induction and confirmation of adequate tube positioning, before surgery. Samples of lung sounds were collected by three piezoelectric microphones, one on each side of the chest and one on the right forearm, for background noise sampling. The samples were filtered, the signals' energy envelopes were calculated, and segmentation to breath and rest periods was performed. Each respiration was classified into one of the three categories: bilateral ventilation, selective right-lung ventilation, or selective left-lung ventilation, on the basis of the ratio between the energy signals of each lung. OLI was accurately identified in 10 of the 11 patients during right OLI and in all 11 patients during left OLI. This study suggests that acoustic monitoring is effective for the detection of selective lung ventilation and may be useful for early diagnosis of OLI.