Major cardiorespiratory events do not increase after immunizations, eye exams, and other stressors in most very low birth weight infants

BACKGROUND: Increased cardiorespiratory events with bradycardia and oxygen desaturation have been reported in very low birthweight (VLBW) infants following stressors such as immunizations. These events are difficult to quantify and may be mild. Our group developed an automated algorithm to analyze bedside monitor data from NICU patients for events with bradycardia and prolonged oxygen desaturation (BDs) and used this to compare BDs 24 hours before and after potentially stressful interventions. METHODS: We included VLBW infants from 2012–2017 with data available around at least one of four interventions: two-month immunizations, retinopathy of prematurity (ROP) examinations, ROP therapy, and inguinal hernia surgery. We used a validated algorithm to analyze electrocardiogram heart rate and pulse oximeter saturation data (HR, SpO2) to quantify BD events of HR < 100 beats/minute for≥4 seconds with oxygen desaturation < 80%SpO2 for≥10 seconds. BDs were analyzed 24 hours before and after interventions using Wilcoxon rank-sum tests. RESULTS: In 354 of 493 (72%) interventions, BD frequency stayed the same or decreased in the 24 hours after the event. An increase of at least five BD’s occurred in 17/146 (12%) after immunizations, 85/290 (29%) after ROP examinations, 4/33 (12%) after ROP therapy, and 3/25 (12%) after hernia surgery. Infants with an increase in BDs after interventions had similar demographics compared to those without. More infants with an increase in BDs following immunizations were on CPAP or caffeine than those without. CONCLUSIONS: Most VLBW infants in our cohort had no increase in significant cardiorespiratory events in the 24 hours following potentially stressful interventions.

Hardware challenges with an anticoagulation strategy guided by detection of atrial fibrillation by an implantable loop recorder

Background A “pill-in-the-pocket” anticoagulation strategy, guided by ECG data from an implantable loop recorder (ILR), has been advocated as a clinical strategy. However, a fundamental requirement is the ability to reliably obtain daily ECG data from patients. Objective To determine the reliability of daily ECG data transfer from ILRs. Methods We evaluated patients implanted with an ILR in whom we sought to withhold oral anticoagulation (OAC) unless atrial fibrillation (AF) was detected. The ILR transmits data nightly to a bedside monitor. Once received, the data are sent to a central server. Over the course of a month, we tracked for each patient whether ECG data were received by the server. Results The study included 170 AF patients with an ILR where we planned to withhold OAC unless AF was documented. Daily ECG data were automatically transmitted and retrievable in only 36 (21%) patients. Two (1%) pts had not a single day of connectivity, 6 (4%) pts were connected &lt;7 days, and 16 (9%) pts were connected &lt;14 days. Wireless connectivity was lost for &gt;48 hours in 89 (52%) patients (Figure). Most patients experienced multiple reasons for data transmission failure within the month. Conclusions To determine whether an ILR guided OAC strategy is feasible, reliable daily transmission of ECG data is a fundamental prerequisite. Current technology facilitated daily ECG data transfer in only 1/5 of patients. In the remaining, there was either extended loss of connectivity or no connectivity at all. A “pill-in-the-pocket” anticoagulation approach is currently difficult given existing hardware limitations. Funding Acknowledgement Type of funding source: None

Orthostatic circulatory disturbances during verticalization in post-comatose patients after severe brain damages

Objectives: Patients in the post-comatose period after critical brain damages and long-term treatment in intensive care units require special approaches to verticalization due to the risk of orthostatic circulatory disorders and deepening of ischemic processes in the brain. Aim: to study orthostatic disorders occurring during verticalization in patients with and without chronic consciousness disorders, after severe brain damages. Material and methods: 72 patients were examined during the post-comatose period, including 49 (68%) after severe stroke, 17 after severe brain injury, 3 patients with posthypoxic encephalopathy and 3 after brain tumor removal. Non-invasive registration of blood pressure (BP) in the brachial artery and monitoring beat to beat of BP was performed using Drager's bedside monitor complete with a finger sensor. Heart rate monitoring was performed automatically by computer-controlled R to R intervals in real time. The results: Orthostatic circulatory disorders were detected in the majority (19 out of 24) of patients with chronic consciousness impairments and in 12 out of 48 patients who were conscious. The most frequent disorder in group 1 was postural tachycardia syndrome, which was not revealed in patients of group 2. Orthostatic hypotension was observed in 25% of group 1 patients and in 20,8% of group 2 patients. Orthostatic hypertension in both groups did not exceed 10%. Conclusion: orthostatic circulatory disorders were revealed in 19 out of 24 patients in group 1 (79,2%) and in 25% in group 2. Application of the new protocol with real-time monitoring of BP and HR allowed to perform verticalization in all patients without complications. The structure of orthostatic circulatory disorders was established, which should be considered at the beginning of the process of verticalization of patients in the post-comatose period after severe brain damages.

Central Apnea of Prematurity: Does Sex Matter?

Objective Apnea is common among infants in the neonatal intensive care unit (NICU). Our group previously developed an automated algorithm to quantitate central apneas with associated bradycardia and desaturation (ABDs). Sex differences in lung disease are well described in preterm infants, but the influence of sex on apnea has not been established. Study Design This study includes infants < 34 weeks' gestation admitted to the University of Virginia NICU from 2009 to 2014 with at least 1 day of bedside monitor data available when not on mechanical ventilation. Waveform and vital sign data were analyzed using a validated algorithm to detect ABD events of low variance in chest impedance signal lasting at least 10 seconds with associated drop in heart rate to < 100 beats/minute and drop in oxygen saturation to < 80%. Male and female infants were compared for prevalence of at least one ABD event during the NICU stay, treatment with caffeine, occurrence of ABDs at each week of postmenstrual age, and number of events per day. Results Of 926 infants studied (median gestational age 30 weeks, 53% male), median days of data analyzed were 19 and 22 for males and females, respectively. There was no sex difference in prevalence of at least one ABD event during the NICU stay (males 62%, females 64%, p = 0.47) or in the percentage of infants treated with caffeine (males 64%, females 67%, p = 0.40). Cumulative prevalence of ABDs from postmenstrual ages 24 to 36 weeks was comparable between sexes. Males had 18% more ABDs per day of data, but this difference was not statistically significant (p = 0.16). Conclusion In this large cohort of infants < 34 weeks' gestation, we did not detect a sex difference in prevalence of central ABD events. There was a nonsignificant trend toward a greater number of ABDs per day in male infants. Key Points

Radiofrequency Monitoring of Intracranial Hemorrhage in the Neurological Intensive Care Unit: A Pilot Trial of the SENSE Device

Intracerebral hemorrhage (ICH) is a devastating form of stroke, with substantial mortality and morbidity. Hemorrhage expansion (HE) occurs in ~40% of patients and portends worse neurologic outcome and mortality. Currently, ICH patients are admitted to the intensive care unit (ICU) and monitored for HE with neurologic exam and neuroimaging. By the time a change is detected, it may be too late to mitigate HE. There is a clinical need for a non-invasive bedside monitor of ICH.The SENSE consists of a 9-antenna array mounted around the head with driving electronics. A 913 MHz signal is transmitted by a given antenna, crosses the intracranial region, and received by the remaining 8 antennae. A complete measurement consists of one cycle with each antenna serving as the transmitting antenna. It was hypothesized that HE of 3 ml would be detected by the device.Ten ICH subjects admitted within 24 hours of stroke onset were enrolled. All patients received a diagnostic head CT (baseline), and a repeat head CT at 12 (+/-6) hours. ICH volumes were determined by blinded neuroradiologist reading, and a significant HE from baseline was considered ≥ 3 ml. Subjects were scanned with the device every 10 minutes for up to 72 hours.Data from one subject was lost from operator error. Among the remaining nine, two experienced HE of ≥ 3ml (3 and 8.2 ml respectively). SENSE device readings were 100% concordant with the CT scan results.

Abstract WMP102: Pilot Study of a Non-invasive Radiofrequency Method to Monitor Intracranial Hemorrhage: A First-in-Human Study

Introduction: Intracerebral hemorrhage (ICH) is a devastating form of stroke. Hemorrhage expansion after ICH occurs in ~40% of patients and leads to worse outcomes. Currently, ICH patients are monitored for hemorrhage expansion by neurologic exam and head CT. CT studies are a source of radiation exposure and can require transporting the patient out of the ICU. There is a clinical need for a non-invasive bedside monitor of ICH. Methods: A radiofrequency based monitor (RFM) was developed as a non-invasive method to monitor ICH at the bedside. The RFM consists of a 9-antenna array mounted around the head, cables, and driving electronics. A 913 MHz signal is transmitted from a given antenna, crosses the brain, and is received by the remaining 8 antennae. A complete measurement consists of one cycle with all antenna serving as the transmitting antenna. As the signal traverses the brain, it is partially scattered and absorbed by the ICH, thus changing the signal at the receiving antennae. The altered signal can be compared to signals at earlier times to detect changes induced by ICH expansion. Based upon pre-clinical work it was hypothesized that ICH expansion of ≥3 ml would be detected by the RFM. The RFM device was approved for human study under an IDE from the FDA. The device was tested on 10 ICH subjects admitted within 24 hours of stroke onset. All subjects received a baseline head CT and a repeat head CT at 12 (+/- 6) hours. ICH volumes were determined by a blinded neuroradiologist. Subjects were scanned with the device every 10 minutes. Results: Data from one subject was lost due to user error. Among the remaining nine, two experienced hemorrhage expansion of ≥ 3ml (3 and 8.2 ml respectively). The RFM readings were 100% concordant with CT scans in identifying presence and absence of hemorrhage expansion. The figure shows monitor readings from a subject with expansion. Conclusion: The RFM may be useful in detection of real-time hemorrhage expansion in ICH patients. A pivotal clinical study is planned.

Design Of Bedside Monitor Based On Microcontroller

A Bedside monitor is the equipment used to monitor patient condition through some parameters that need sustainable monitoring so that the patient condition is always monitored. This research is monitored by 5 parameters namely heart signal, heart rate, temperature, respiration and SPO2. This research applies quasi experimental design. The free variable is an ECG phantom or human, and the dependent variable is a bedside monitor. The research instruments are a calibration equipment of ECG signal, temperature, and respiration. The result of the heart signal lead 2 is not different from the standard and the result of the heart rate lead has uncertainty (probability) 0 for Lead 2; which is still under the tolerance number (0.5). The results of the temperature measurement of 5 samples with 5 measurements show that there are 3 samples which have standard deviation and 0 (zero) uncertainty, whereas 2 samples have 0.76 (higher than 0.5) uncertainty. This condition is influenced by the patient movements, so the sensor attached on the patient-body does not fit with the standard installation. The respiration measurement results have an accuracy of 98%, while the SPO2 results have a standard deviation and uncertainty below 5% after being compared with the standard calculations. Here are the details: standard deviation 0.894427; 0.547723; 0.44; Probability 0.4; 0.244949; 0.2 and 0.2. Overall, it can be concluded that The Design of Bedside Monitor Based on Microcontroller is feasible and the measurement result of heart signal Lead 2, heart rate, temperature, respiration, SPO2 can be presented on a PC.

Analysis of ECG Signals Recorded Using Different Stimuli from Patients in Intensive Care Unit: A Case Study

Intensive Care Units (ICUs) are more difficult and complex areas of hospital as treatment and care. In these units, the patients are monitored continuously with a bedside monitor for respiration, O2 saturation and pulse information. However, this information, which is periodically noted on the patient observation papers, may not represent a definite diagnose/follow up about the patient&apos;s health condition in all times. Therefore, in order to assist the physician in these units where the diagnosis/follow up is important, attributes are extracted from ECG signals easy-to-obtain by using signal processing methods. ECG signals were obtained from 3 patients at different days. Attributes were analyzed statistically to see if the patient reacted to oral/touch stimuli and to monitor his / her health condition. As a result, it was possible to evaluate the coma patients&apos; response to stimuli and to follow-up for improving physiological well-being using ECG signals.