Invasive Monitoring In Patients Research Articles

AI-produced certainties in health care: current and future challenges

AbstractSince uncertainty is a major challenge in medicine and bears the risk of causing incorrect diagnoses and harmful treatment, there are many efforts to tackle it. For some time, AI technologies have been increasingly implemented in medicine and used to reduce medical uncertainties. What initially seems desirable, however, poses challenges. We use a multimethod approach that combines philosophical inquiry, conceptual analysis, and ethical considerations to identify key challenges that arise when AI is used for medical certainty purposes. We identify several challenges. Where AI is used to reduce medical uncertainties, it is likely to result in (a) patients being stripped down to their measurable data points, and being made disambiguous. Additionally, the widespread use of AI technologies in health care bears the risk of (b) human physicians being pushed out of the medical decision-making process, and patient participation being more and more limited. Further, the successful use of AI requires extensive and invasive monitoring of patients, which raises (c) questions about surveillance as well as privacy and security issues. We outline these several challenges and show that they are immediate consequences of AI-driven security efforts. If not addressed, they could entail unfavorable consequences. We contend that diminishing medical uncertainties through AI involves a tradeoff. The advantages, including enhanced precision, personalization, and overall improvement in medicine, are accompanied by several novel challenges. This paper addresses them and gives suggestions about how to use AI for certainty purposes without causing harm to patients.

P58 SCREENING FOR SUBCLINICAL ATRIAL FIBRILLATION AFTER EMBOLIC STROKE OF UNDETERMINED SOURCE: A SINGLE CENTRE EXPERIENCE

Abstract Introduction Embolic stroke of undetermined source (ESUS) describes a stroke for which no cause has been found, which implicates embolism as a cause of stroke. There are several mechanisms of cryptogenic ischemic stroke including a covert structural cardiac lesion, paroxysmal atrial fibrillation (AF), hypercoagulable state or undiagnosed malignancy. As ESUS is associated with a significant stroke recurrence, a clear risk prediction and management is of utmost importance to improve prognosis. In ESUS, the options for further investigation include long–term cardiac monitoring, transesophageal echocardiography, investigation for occult malignancy or arterial hypercoagulability. Implantable cardiac monitors offer the capability to maximize the chances to detect AF and should be considered after non–invasive monitoring in patients with previous stroke at higher probability of having AF. Current guidelines do not suggest a specified approach (ie, blood, echocardiographic, ECG or brain imaging biomarkers) to screen AF in ESUS patients. Methods We enrolled consecutive patients with ESUS admitted to our Stroke Unit from January 2021 to October 2022. Results In the study period, 509 patients with acute ischemic stroke were admitted in our Stroke Unit. ESUS was diagnosed in 10.6% of patients (54/509). Only 12 of these patients underwent loop recorder implantation (mean age 76.5 y, 75% male), according to clinician judgment. AF was detected in 16.6% of these patients (2/12). Conclusions AF is one of the causes of ESUS; a recognition of AF in these patients is important, because its treatment can modify the risk of recurrence. A tailored diagnostic pathway, including clinical and echocardiographic parameters, is advisable to improve the recognition of this arrhythmia in ESUS patients.

Trans-Interhemispheric Stereoelectroencephalography Depth Electrode Placement for Mesial Frontal Lobe Explorations in Medically Refractory Epilepsy: A Technical Note and Case Series.

Stereoelectroencephalography (SEEG) is an established and safe methodology for extra-operative invasive monitoring in patients with medical refractory epilepsy. SEEG has several advantages such as the ability to record deep cortical structures, mapping the epileptogenic zone in a three-dimensional manner, and analyze bihemispheric regions without the need for bilateral craniotomies. In patients with bilateral hemispheric hypotheses, especially the mesial surface of frontal lobes, bilateral lead placement is compulsory to further define and localize the epileptogenic zone. In this particular cohort of patients, bilateral monitoring may be accomplished from a single entry point using trans-interhemispheric placement of the electrodes. The use of trans-interhemispheric monitoring offers several advantages including sparing the need for additional leads. To test the hypothesis that, given the lack of the falx as a limiting structure in the ventral and mesial frontal lobe regions, trans-interhemispheric SEEG placement is feasible and a potential benefit for the SEEG method. We report on 6 patients who underwent bilateral monitoring using trans-interhemispheric SEEG lead placement and discuss the operative technique. Six patients underwent trans-interhemispheric monitoring, with a median of 3 leads per patient (19 total). Trajectory error was minimal (<0.3 mm), and operating room time was comparable with that in previous reports. All leads were placed without adverse events, mislocalization, electrode hemorrhages, or any other complications. All patients had successful localization of the epileptogenic zone. Trans-interhemispheric SEEG to monitor the mesial wall of frontal lobe regions is technically feasible. No adverse events were observed, suggesting a favorable safety profile.

A hierarchical anatomical framework and workflow for organizing stereotactic encephalography in epilepsy.

Stereotactic electroencephalography (SEEG) is an increasingly utilized method for invasive monitoring in patients with medically intractable epilepsy. Yet, the lack of standardization for labeling electrodes hinders communication among clinicians. A rational clustering of contacts based on anatomy rather than arbitrary physical leads may help clinical neurophysiologists interpret seizure networks. We identified SEEG electrodes on post‐implant CTs and registered them to preoperative MRIs segmented according to an anatomical atlas. Individual contacts were automatically assigned to anatomical areas independent of lead. These contacts were then organized using a hierarchical anatomical schema for display and interpretation. Bipolar‐referenced signal cross‐correlations were used to compare the similarity of grouped signals within a conventional montage versus this anatomical montage. As a result, we developed a hierarchical organization for SEEG contacts using well‐accepted, free software that is based solely on their post‐implant anatomical location. When applied to three example SEEG cases for epilepsy, clusters of contacts that were anatomically related collapsed into standardized groups. Qualitatively, seizure events organized using this framework were better visually clustered compared to conventional schemes. Quantitatively, signals grouped by anatomical region were more similar to each other than electrode‐based groups as measured by Pearson correlation. Further, we uploaded visualizations of SEEG reconstructions into the electronic medical record, rendering them durably useful given the interpretable electrode labels. In conclusion, we demonstrate a standardized, anatomically grounded approach to the organization of SEEG neuroimaging and electrophysiology data that may enable improved communication among and across surgical epilepsy teams and promote a clearer view of individual seizure networks.

Attitudes of Clinicians in Using Invasive Monitoring in Patients With Heart Failure

Attitudes of Clinicians in Using Invasive Monitoring in Patients With Heart Failure

Temporal lobe surgery for intractable epilepsy in children: What to do with the hippocampus?

PurposeResection of the hippocampus can cause verbal memory decline, especially in the pediatric population. Thus, preservation of the hippocampus can be crucial for the quality of life of children with intractable temporal lobe epilepsy (TLE) who are candidates for epilepsy surgery. We investigated techniques that determine whether the hippocampus is part of the epileptogenic zone and the outcomes of pediatric surgery aimed to spare the hippocampus. MethodsWe accessed data of children with normal hippocampus on MRI, who underwent surgery for medically refractory TLE. To identify epileptogenic areas, electrocorticography was performed in patients with space occupying lesions adjacent to the hippocampus, and long term invasive monitoring in patients with nonlesional TLE. Postoperative seizure control was classified according to Engel I-IV; Class I indicates seizure-free. ResultsEleven females and 11 males met study inclusion criteria; the mean age at surgery was 11.3 years. Cortical and hippocampal electrocorticography was performed in 15 patients and long term invasive hippocampal monitoring in seven. The hippocampus was preserved in 16 patients (73%) while hippocampectomy was performed in 6 (27%). At the end of a mean follow-up of 3.5 years, 94% (15/16) of the patients who did not undergo hippocampectomy were classified as Engel I, compared to 50% (3/6) who underwent hippocampectomy. ConclusionSparing the hippocampus in temporal lobe epilepsy surgery is possible with excellent seizure outcome, while using the proper intraoperative technique.

Stereoelectroencephalography in the “difficult to localize” refractory focal epilepsy: Early experience from a North American epilepsy center

Stereo-electroencephalography (SEEG) enables precise recordings from deep cortical structures, multiple noncontiguous lobes, as well as bilateral explorations while avoiding large craniotomies. Despite a long reported successful record, its application in the United States has not been widely adopted. We report on our initial experience with the SEEG methodology in the extraoperative mapping of refractory focal epilepsy in patients who were not considered optimal surgical candidates for other methods of invasive monitoring. We focused on the applied surgical technique and its utility and efficacy in this subgroup of patients. Between March 2009 and May 2011, 100 patients with the diagnosis of medically refractory focal epilepsy who were not considered optimal candidates for subdural grids and strips placement underwent SEEG implantation at Cleveland Clinic Epilepsy Center. Demographics, noninvasive clinical data, number and location of implanted electrodes, electrophysiologic localization of the epileptic zone, complications, and short-term seizure outcome after resection were prospectively collected and analyzed. Mean age was 32 years (range 5-68 years); 54 were male and 46 female. The mean follow-up after resection was 15 months. In total, 1,310 electrodes were implanted. Analyses of the SEEG recordings resulted in the electrographic localization of the epileptogenic focus in 96 patients. In the group of 75 patients who underwent resection, only 53 had at least 12 months follow-up. From this group, 33 patients (62.3%) were seizure-free at the end of the follow-up period. The presence of abnormal pathologic finding was strongly associated with postoperative seizure control (p = 0.005). The risk of hemorrhagic complications per electrode was 0.2%. In patients who are not considered to be ideal candidates for subdural grids and strips implantation, the SEEG methodology is a safe, useful and reliable alternative option for invasive monitoring in patients with refractory focal epilepsy, providing an additional mean for seizure localization and control in a "difficult to localize" subgroup of patients.

Tu1802 Laparoscopic Bariatric Surgery is Safe in Patients With Mild to Moderate Pulmonary Hypertension

Background: Pulmonary hypertension (PH) has significant perioperative risks that may outweigh the benefit of elective surgery. There is very little data on laprascopic surgery in the setting of PH. Our objective was to look at our outcomes of bariatric surgery in patients with PH. Methods: A retrospective review of a prospectively gathered database of all bariatric procedures was conducted for patients treated from 2007-2011. All patients with PH who underwent a bariatric procedure were reviewed for their preoperative evaluation, intraoperative monitoring and management, post-operative care, and clinic follow up. Results: 809 bariatric procedures were performed from 2007-2011, 5 patients (0.6%), 3 males and 2 females, had PH. 2 patients had Type 1 PH, 2 had Type III PH, and the final patient did not have information on the etiology. The mean PAP of the 5 patients was 40 mmHG (range 25-60). The mean age of the patients was 58 years of age, and the mean BMI was 52. 3 laparoscopic Roux-N-Y, 1 laparoscopic sleeve gastrectomy, and 1 laparoscopic band were performed. Invasive monitoring, arterial line and/or pulmonary catheter, was used in 2 patients with mean PAP ≥ 40. There were no intra-operative complications and only one patient had a long term complication; band slipped and underwent removal. The mean length of stay was 2 days and mean follow up was 8 months. Mean excess body weight loss (EBL) at 3 months was 29% (N=5), at 6 months was 42% (N=4), and at 1 year 35% (N=2). Over an average of 6 months, exercise tolerance in all 3 Roux-N-Y patients was doubled in terms of length of exercise time and distance walking, and remained the same in the other two. Postoperative pulmonary hypertension follow up with 2d echo was only performed in one patient. A decrease of mean PAP from 39 to 26, 1 year after surgery, without concomitant change in medical therapy was demonstrated. Conclusions: Laparoscopic surgery seems safe in patients with pulmonary hypertension without significant morbidity, mortality or increased length of stay. Invasive monitoring in patients with mean PAP > 25mmHG<40mmHG may not be necessary. Exercise tolerance improves in most patients. EBL was modest but few patients had 1 year follow up. Further research is needed to determine long term weight loss, improvement in comorbidities and improvement in PH.

Invasive monitoring in patients with heart failure

The syndrome of heart failure is characterized by symptoms that are relatively insensitive and nonspecific. Physical diagnosis may be unreliable even in the hands of experienced clinicians, despite the presence of significantly elevated filling pressures or a significantly depressed cardiac output. Instrumentation and devices such as the insertion of a pulmonary artery catheter and the implantable hemodynamic monitor have a major role in the diagnosis and management of cardiovascular disease. They provide a means of measuring intracardiac pressures for point-in-time measurements (cardiac catheterization), short term in an acute situation (insertion of a pulmonary arterial catheter), and, more recently, a long-term assessment increasing our understanding of the nuances of the hemodynamic derangements associated with heart failure and other conditions. With improved ability to accurately assess and monitor filling pressures, clinicians can more precisely adjust therapy with the goal of improving patient symptoms and possibly outcomes.

Nonhabitual Seizures in Patients with Implanted Subdural Electrodes

The implantation of subdural electrodes has been widely employed in the invasive monitoring of patients with medically refractory epilepsy. The use of subdural electrodes, though, has been associated with rare but occasionally troublesome complications. We report the occurrence of nonhabitual seizures after implanting subdural grid electrodes. Among 57 patients diagnosed with medically refractory epilepsy who were evaluated in our department over a 12-month period, 21 patients underwent craniotomy for subdural grid/strip electrode implantation. Subdural grids and strips (AdTech, Racine, Wisc., USA) were used for continuous video EEG monitoring. In 3 patients, during subdural monitoring, consistent nonhabitual seizure activity was recorded. This was both clinically and electrographically different than the patients’ habitual seizures. The patients’ nonhabitual seizures disappeared postoperatively after removing the implanted electrodes. The occurrence of nonhabitual seizures, though quite rare, could lead to mislocalization of an epileptogenic focus. This complication might be the result of direct mechanical cortical irritation or chemical irritation caused by blood breakdown products. The occurrence of nonhabitual seizures comes to add itself to the existing list of complications associated with employment of subdural electrodes for invasive monitoring.

Paradigms for subdural grids' implantation in patients with refractory epilepsy.

The need for invasive monitoring in patients with refractory epilepsy has been greatly reduced by the introduction of new technologies such as PET, SPECT and MRI in the clinical practice. On the other hand, 10 to 30% of the patients with refractory epilepsy have non-localizatory non-invasive preoperative work-up results. This paper reports on the paradigms for subdural electrodes implantation in patients with different refractory epileptic syndromes. Twenty-nine adult refractory epileptic patients were studied. Patients were divided into five different epileptic syndromes that represented the majority of the patients who needed invasive recordings: bitemporal (Group I; n=16 ), bi-frontal-mesial (Group II, n=5), hemispheric (Group III; n=2), anterior quadrant (Group IV; n=3) and posterior quadrant (Group V; n=3). All of them were submitted to extensive subdural electrodes' implantation (from 64 to 160 contacts) covering all the cortical surface potentially involved in epileptogenesis under general anesthesia. All patients tolerated well the procedure. There was no sign or symptom of intracranial hypertension except for headache in 22 patients. In all except one Group II patient, prolonged electrocorticographic monitoring using the described subdural cortical coverage patterns was able to define a focal area amenable for resection. In all Groups II-V patients cortical stimulation was able to adequately map the rolandic and speach areas as necessary. Despite recent technological advances invasive neurophysiological studies are still necessary in some patients with refractory epilepsy. The standardization of the paradigms for subdural implantation coupled to the study of homogeneous patients' populations as defined by MRI will certainly lead to a better understanding of the pathophysiology involved in such cases and an improved surgical outcome.

Epilepsy surgery.

Only 15% of patients with severe epilepsy with frequent partial seizures achieve any improvement in their seizure frequency by further drug treatment. As we know that epileptic seizures result in neuron loss with early development of mental deterioration, that the mortality rate of patients with epilepsy is increased and that an exact localization of the epileptogenic area which can be resected offers the possibility of curative treatment, we have a moral obligation to make this treatment available to people disabled with epilepsy. Surgery for mesial temporal sclerosis and lesional cortical partial epilepsy offers freedom from seizures in 70-80% of the patients, whereas non-lesional, cortical, partial epilepsy is more problematic, as only 30-40% of the patients will be seizure-free. Volumetric MRI, MR spectroscopy, SPECT and PET reduce the need for invasive monitoring in patients with temporal lobe epilepsy. Invasive recordings should be used when scalp-EEG, MRI, SPECT and PET cannot identify the epileptic focus; 50% of the patients who cannot be diagnosed by non-invasive recordings, can be diagnosed by invasive methods. When operated on 70% become seizure free, and a further 10% achieve a significant improvement. As age at surgery influences vocational outcome, surgical therapy should be considered in children. This will prevent their development into chronically ill patients, with all the known accompanying psychic handicaps this involves.