Armagan Dagal

Cerebral autoregulation and anesthesia.

Purpose of review This review will examine the recent literature on anesthesia and monitoring techniques in relation to cerebral autoregulation. We will discuss the effect of physiologic and pharmacological factors on cerebral autoregulation alongside its clinical relevance with the help of new evidence. Recent findings Intravenous anesthesia, such as combination of propofol and remifentanil, provides best preservation of autoregulation. Among inhaled agents sevoflurane appears to preserve autoregulation at all doses, whereas with other agents autoregulation is impaired in a dose-related manner. Summary Intraoperative cerebral autoregulation monitoring is an important consideration for the patients with neurologic disease. Transcranial Doppler based static autoregulation measurements appears to be the most robust bedside method for this purpose.

Cerebral blood flow and the injured brain: how should we monitor and manipulate it?

Purpose of review Cerebral ischemia plays a major role in the pathophysiology of the injured brain, including traumatic brain injury and subarachnoid hemorrhage, thus improvement in outcome may necessitate monitoring and optimization of cerebral blood flow (CBF). To interpret CBF results in a meaningful way, it may be necessary to quantify cerebral autoregulation as well as cerebral metabolism. This review addresses the recent evidence related to the changes in CBF and its monitoring/management in traumatic brain injury. Recent findings Recent evidence on the management of patients with traumatic brain injury have focused on the importance of cerebral autoregulation in maintaining perfusion, which necessitates the measurement of CBF. However, adequate CBF measurements alone would not indicate the amount of oxygen delivered to neuronal tissues. Technologic advancements in measurement devices have enabled the assessment of the metabolic state of the cerebral tissue for the purpose of guiding therapy, progress as well as prognostification. Summary Current neurocritical care management strategies are focused on the prevention and limitation of secondary brain injury where neuronal insult continues to evolve during the hours and days after the primary injury. Appropriately chosen multimodal monitoring including CBF and management measures can result in reduction in mortality and morbidity.

Occurrence and complications of tracheal reintubation in critically ill adults.

BACKGROUND: Timing and preparation for tracheal extubation are as critical as the initial intubation. There are limited data on specific strategies for a planned extubation. The extent to which the difficult airway at reintubation contributes to patient morbidity is unknown. The aim of the present study was to describe the occurrence and complications of failed extubation and associated risk factors, and to estimate the mortality and morbidity associated with reintubation attempts. METHODS: Cohort study of 2,007 critically ill adult patients admitted to the ICU with an ETT. Patients were classified in 2 groups, based on the requirement for reintubation: “never reintubated” versus “≥ 1 reintubations.” Baseline characteristics, ICU and hospital stay, hospital mortality, and in-patient costs were compared between patients successfully extubated and those with reintubation outside the operating room, using regression techniques. Reasons, airway management techniques, and complications of intubation and reintubation were summarized descriptively. RESULTS: 376 patients (19%) required reintubation, and 230 (11%) were reintubated within 48 hours, primarily due to respiratory failure. Patients requiring reintubation were older, more likely to be male, and had higher admission severity score. Difficult intubation and complications were similar for initial and subsequent intubation. Reintubation was associated with a 5-fold increase in the relative odds of death (adjusted odds ratio 5.86, 95% CI 3.87–8.89, P < .01), and a 2-fold increase in median ICU and hospital stay, and institutional costs. Difficult airway at reintubation was associated with higher mortality (adjusted odds ratio 2.23, 95% CI 1.01–4.93, P = .05). CONCLUSIONS: Nearly 20% of critically ill patients required out of operating room reintubation. Reintubation was associated with higher mortality, stay, and cost. Moreover, a difficult airway at reintubation was associated with higher mortality.

Predictors of Reintubation in Critically Ill Patients

BACKGROUND: Assessment of a patients readiness for removal of the endotracheal tube in the ICU is based on respiratory, airway, and neurological measures. However, nearly 20% of patients require reintubation. We created a prediction model for the need for reintubation, which incorporates variables importantly contributing to extubation failure. METHODS: This was a cohort study of 2,007 endotracheally intubated subjects who required ICU admission at a tertiary care center. Data collection included demographic, hemodynamic, respiratory, and neurological variables preceding extubation. Data were compared between subjects extubated successfully and those who required reintubation, using bivariate logistic regression models, with the binary outcome reintubation and the baseline characteristics as predictors. Multivariable logistic regression analysis with robust variance was used to build the prediction model. RESULTS: Of the 2,007 subjects analyzed, 376 (19%) required reintubation. In the bivariate analysis, admission Simplified Acute Physiology Score II, minute ventilation, breathing frequency, oxygenation, number of prior SBTs, rapid shallow breathing index, airway-secretions suctioning frequency and quantity, heart rate, and diastolic blood pressure differed significantly between the extubation success and failure groups. In the multivariable analysis, higher Simplified Acute Physiology Score II and suctioning frequency were associated with failed extubation. The area under the receiver operating characteristic curve was 0.68 for failure at any time, and 0.71 for failure within 24 hours. However, prior failed SBT, minute ventilation, and diastolic blood pressure were additional independent predictors of failure at any time, whereas oxygenation predicted extubation failure within 24 hours. CONCLUSIONS: A small number of independent variables explains a substantial portion of the variability of extubation failure, and can help identify patients at high risk of needing reintubation. These characteristics should be incorporated in the decision-making process of ICU extubation.

Radiation safety for anesthesiologists.

Purpose of review To review the recent literature on the implications of occupational radiation exposure in anesthesia practice. Recent findings Wide variation and lack of reduction in operator doses of medical radiation strongly suggests that more attention must be paid to the factors influencing radiation dose exposure. The eye is likely the most sensitive organ for radiation injury. Radiation-related cataract formation might be a stochastic effect. Operators are strongly advised to use eye protection at all times. Safe medical radiation ophthalmic dose limits are currently under review and are likely to be lowered. Current data do not suggest a significant risk to the fetus for pregnant women working in the interventional radiology suite as long as proper monitoring and radiation safety measures are implemented. Summary Radiation is increasingly utilized in medicine for diagnostic and therapeutic procedures. Anesthesia providers may become exposed to unsafe doses while providing high-quality patient care. Understanding of the physical principles, the sources of radiation exposure, the potential risks, and safe practices helps to minimize the exposure risk and its potential deleterious effects to the anesthesia team.

A National Survey of Airway Management Training in United States Internal Medicine-Based Critical Care Fellowship Programs

BACKGROUND: Intensivists may be primarily responsible for airway management in non-operating room locations. Little is known of airway management training provided during fellowship. Our primary aim was to describe the current state of airway education in internal medicine-based critical care fellowship programs. METHODS: Between February 1 and April 30, 2011, program directors of all 3-year combined pulmonary/critical care and 2-year multidisciplinary critical care medicine programs in the United States were invited to complete an online survey. Contact information was obtained via FRIEDA Online (https://freida.ama-assn.org). Non-responders were sent automated reminders, were contacted by e-mail, or by telephone. RESULTS: The overall response proportion was 66% (111/168 programs). Sixty-four (58%) programs reported a designated airway rotation, chiefly occurring for 1 month during the first year of training. Thirty-five programs (32%) reported having a director of airway education and 78 (70%) reported incorporating simulation-based airway education. Nearly all programs (95%) reported provision of supervised airway experience during fellowship. Commonly used airway management devices, including video laryngoscopes, intubating stylets, supraglottic airway devices, and fiberoptic bronchoscopes, were reportedly available to trainees. However, 73% reported ≤ 10 uses of a supraglottic airway device, 60% ≤ 25 uses of intubating stylets, 73% ≤ 30 uses of a video laryngoscope, and 65% reported ≤ 10 flexible fiberoptic intubations. Estimates of the required number of procedures to ensure competence varied widely. CONCLUSIONS: The majority of programs have a formal airway management program incorporating a variety of intubation techniques. Overall experience varies widely, however.

International disparities in trauma care

Purpose of review Trauma care has been a low priority topic in the global health agenda until recently, despite its social and economic impact. Although prevention is the key, provision and quality of trauma care has been the weakest link in the survival chain. We aim to summarize the differences in global trauma care to propose solutions in this article. Recent findings Patients with life-threatening injuries are six times more likely to die following a trauma in a low-income country than in a high-income country. Unintentional injuries currently rank fourth in the global causes of death, resulting in 5.8 million premature deaths and millions more with disability. The WHO member countries started the first global Decade of Action for Road Safety 2011–2020 initiative in May 2011. Governments across the world agreed to take steps to improve the safety of roads and vehicles, enhance the behavior of all road users and strengthen post-trauma care. Summary Several core strategies have been identified: human resource planning; physical resources (equipment and supplies); and administration (quality improvement and data collection) need to be developed for effective and adaptable prehospital care, patient transfer, in-hospital care and rehabilitation systems for injured persons worldwide. Clear definition of the problem to propose solutions is critical.

Anesthetic considerations in acute spinal cord trauma

Patients with actual or potential spinal cord injury (SCI) are frequently seen at adult trauma centers, and a large number of these patients require operative intervention. All polytrauma patients should be assumed to have an SCI until proven otherwise. Pre-hospital providers should take adequate measures to immobilize the spine for all trauma patients at the site of the accident. Stabilization of the spine facilitates the treatment of other major injuries both in and outside the hospital. The presiding goal of perioperative management is to prevent iatrogenic deterioration of existing injury and limit the development of secondary injury whilst providing overall organ support, which may be adversely affected by the injury. This review article explores the anesthetic implications of the patient with acute SCI. A comprehensive literature search of Medline, Embase, Cochrane database of systematic reviews, conference proceedings and internet sites for relevant literature was performed. Reference lists of relevant published articles were also examined. Searches were carried out in October 2010 and there were no restrictions by study design or country of origin. Publication date of included studies was limited to 1990–2010.

Development and Validation of a Prediction Model for Pain and Functional Outcomes After Lumbar Spine Surgery

Importance Functional impairment and pain are common indications for the initiation of lumbar spine surgery, but information about expected improvement in these patient-reported outcome (PRO) domains is not readily available to most patients and clinicians considering this type of surgery. Objective To assess population-level PRO response after lumbar spine surgery, and develop/validate a prediction tool for PRO improvement. Design, Setting, and Participants This statewide multicenter cohort was based at 15 Washington state hospitals representing approximately 75% of the state’s spine fusion procedures. The Spine Surgical Care and Outcomes Assessment Program and the survey center at the Comparative Effectiveness Translational Network prospectively collected clinical and PRO data from adult candidates for lumbar surgery, preoperatively and postoperatively, between 2012 and 2016. Prediction models were derived for PRO improvement 1 year after lumbar fusion surgeries on a random sample of 85% of the data and were validated in the remaining 15%. Surgical candidates from 2012 through 2015 were included; follow-up surveying continued until December 31, 2016, and data analysis was completed from July 2016 to April 2017. Main Outcomes and Measures Functional improvement, defined as a reduction in Oswestry Disability Index score of 15 points or more; and back pain and leg pain improvement, defined a reduction in Numeric Rating Scale score of 2 points or more. Results A total of 1965 adult lumbar surgical candidates (mean [SD] age, 61.3 [12.5] years; 944 [59.6%] female) completed baseline surveys before surgery and at least 1 postoperative follow-up survey within 3 years. Of these, 1583 (80.6%) underwent elective lumbar fusion procedures; 1223 (77.3%) had stenosis, and 1033 (65.3%) had spondylolisthesis. Twelve-month follow-up participation rates for each outcome were between 66% and 70%. Improvements were reported in function, back pain, and leg pain at 12 months by 306 of 528 surgical patients (58.0%), 616 of 899 patients (68.5%), and 355 of 464 patients (76.5%), respectively, whose baseline scores indicated moderate to severe symptoms. Among nonoperative patients, 35 (43.8%), 47 (53.4%), and 53 (63.9%) reported improvements in function, back pain, and leg pain, respectively. Demographic and clinical characteristics included in the final prediction models were age, sex, race, insurance status, American Society of Anesthesiologists score, smoking status, diagnoses, prior surgery, prescription opioid use, asthma, and baseline PRO scores. The models had good predictive performance in the validation cohort (concordance statistic, 0.66-0.79) and were incorporated into a patient-facing, web-based interactive tool (https://becertain.shinyapps.io/lumbar_fusion_calculator). Conclusions and Relevance The PRO response prediction tool, informed by population-level data, explained most of the variability in pain reduction and functional improvement after surgery. Giving patients accurate information about their likelihood of outcomes may be a helpful component in surgery decision making.

A Technique to Allow Prone Positioning in the Spine Surgery Patient With Unstable Spine Fracture and Flail Segment Rib Fractures.

Two patients with unstable thoracic spine and flail segment rib fractures initially failed prone positioning on a Jackson spinal table used for posterior spinal instrumentation and fusion surgery. Both patients experienced rapid hemodynamic collapse. We developed a solution using the anterior portions of a thoracolumbosacral orthosis brace as chest supports to use during prone positioning, allowing both patients to undergo uncomplicated posterior spinal instrumentation and fusion surgeries with greater hemodynamic stability.