Geometrical and Hemodynamic Variables for Thrombotic Risk Stratification in Kawasaki Disease

Objectives Thrombosis is a major adverse outcome for coronary artery aneurysms (CAA) in Kawasaki disease (KD). We investigated the geometric and hemodynamic abnormalities in patients with CAA and identified the risk factors for thrombosis by computational fluid dynamics (CFD) simulation. Methods We retrospectively studied 27 KD patients with 77 CAAs, including 20 CAAs with thrombosis in 12 patients. Patient-specific anatomic models obtained from cardiac magnetic resonance imaging (CMRI) were constructed to perform a CFD simulation. From the simulation results, we produced local hemodynamic parameters comprising of time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI) and relative resident time (RRT). The CAA’s maximum diameter (Dmax) and Z-score were measured on CMRI. Results Giant CAAs tended to present with more severe hemodynamic abnormalities. Thrombosed CAAs exhibited lower TAWSS (1.551 ± 1.535 vs. 4.235 ± 4.640dynes/cm2, p = 0.002), higher Dmax (10.905 ± 4.125 vs. 5.791 ± 2.826mm, p = 0.008), Z-score (28.301 ± 13.558 vs. 13.045 ± 8.394, p = 0.002), OSI (0.129 ± 0.132 vs. 0.046 ± 0.080, p = 0.01), and RRT (16.780 ± 11.982s vs. 9.123 ± 11.770s, p = 0.399) than the non-thrombosed group. An ROC analysis for thrombotic risk proved that all of the five parameters had area under the ROC curves (AUC) above 0.7, with Dmax delineating the highest AUC (AUCDmax = 0.871) and a 90% sensitivity, followed by Z-score (AUCZ−score = 0.849). Conclusions It is reasonable to combine the geometric index with hemodynamic information to establish a severity classification for KD cases.

Comparison of two-lung and one-lung ventilation in bilateral video-assisted thoracoscopic extended thymectomy in myasthenia gravis: a retrospective study

Background: Myasthenia gravis (MG) is an autoimmune disease, and early thymectomy is recommended. Since the introduction of video-assisted thoracoscopic surgery, the safety and effectiveness of carbon dioxide insufflation in the thoracic cavity (capnothorax) has been controversial. This study aimed to compare the safety and effectiveness of ventilation methods in bilateral video-assisted thoracoscopic extended thymectomy (BVET) with capnothorax.Methods: We retrospectively investigated the medical records of patients with MG who underwent BVET between August 2016 and January 2018. Patients were divided into two groups: group D (n = 26) for one-lung ventilation and group S (n = 28) for two-lung ventilation. We set nine anesthesia time points (T0–T8) and collected respiratory and hemodynamic variables, including arterial O2 index (PaO2/FiO2).Results: SpO2 at T1–T3 and T8 was significantly lower in group D than in group S. The FiO2 in group S was lower than that in group D at all time points. The number of PaO2/FiO2 ≤ 300 and PaO2/FiO2 ≤ 200 events was significantly higher in group D than in group S. Hemodynamic variables were not significantly different between the two groups at any time point. The duration of surgery and anesthesia was shorter in group S than in group D. Conclusions: This retrospective study suggests that anesthesia using two-lung ventilation during BVET with capnothorax is a safe and effective method to improve lung oxygenation and reduce anesthesia time.

Impact of Maternal Lateral Tilt On Cardiac Output During Caesarean Section Under Spinal Anaesthesia: A Prospective Observational Study

Background: Left uterine displacement (LUD) has been questioned as an effective strategy to prevent aortocaval compression after spinal anesthesia (SA) for cesarean delivery (CD). We tested if LUD has a significant impact on cardiac output (CO) in patients undergoing CD under SA during continuous non-invasive hemodynamic monitoring.Methods: Forty-six patients were included in the final analysis. We considered 4 timepoints of 5 minutes each: T1=baseline with LUD; T2=baseline without LUD; T3=after SA with LUD; T4=after SA without LUD. LUD was then repositioned for CD. Primary outcome was to test if CO decreased from T3 to T4. We also compared CO between T1 and T2 and other hemodynamic variables: mean, systolic and diastolic blood pressure (respectively MAP, SAP and DAP), heart rate (HR), stroke volume (SV), stroke volume variation (SVV), pulse pressure variation (PPV), contractility (dP/dt), dynamic arterial elastance (Eadyn) at the different timepoints. Data on fetal Apgar scores and umbilical arterial and venous pH were collected.Results: CO did not vary from T3 to T4 [CO mean difference -0.02 L/min [95% CI -0.88 to 0.82; p=1]. No significant variation was registered for any variable at any timepoint. Conclusions: LUD did not show a significant impact on CO during continuous hemodynamic monitoring after SA for CD.Trial registration: (retrospectively registered on 03/12/2021) NCT05143684.

Choosing the Best Method for Hemodynamic Monitoring

Optimizing hemodynamics improves patient outcomes in critically ill patients. There are many types of hemodynamic monitoring. When choosing the monitoring type, factors include accuracy, invasiveness, the desired hemodynamic variables, and potential complications. For example, the Pulmonary Artery Catheter is invasive and can be associated with catheter-related complications. Still, the values it provides have been validated and may be more useful when treating patients with heart problems. New minimally invasive and noninvasive hemodynamic monitoring systems, such as the Flo Trac and the ClearSight, deliver functional hemodynamic values that can be used to evaluate the real-time response to fluid administration. Minimally invasive and noninvasive devices’ ease of use, availability, and relative lack of patient complications make them appealing. However, they may lack accuracy in some situations.

Immediate Hemodynamic Responses to Transcutaneous Electrical Diaphragmatic Stimulation in Critically Ill Elderly Patients

Background. Critically ill patients admitted to intensive care units (ICUs) may develop diaphragmatic dysfunction, especially when artificial airways are used. Positive effects have been observed when using the transcutaneous electrical diaphragmatic stimulation (TEDS) technique in different clinical conditions. However, no study has evaluated the safety of TEDS in patients admitted to ICUs. This study is aimed at evaluating the influence of TEDS on the hemodynamic and vital parameters of critically ill elderly patients under invasive mechanical ventilation (IMV). Methods. Forty-seven patients aged >60 years under IMV were evaluated for hemodynamic variables before and after TEDS. The procedure lasted 30 minutes and was performed once. Results. The sample consisted of 33 men and 14 women with a mean age of 69.9 ± 7.64 years. The mean systolic blood pressures pre-TEDS and post-TEDS were 126.6 ± 23.7 and 122.9 ± 25.9 , respectively ( p = 0.467 ). The mean diastolic blood pressures pre-TEDS and post-TEDS were 71.1 ± 12.2 and 67.7 ± 14.2 , respectively ( p = 0.223 ). No significant differences in the mean arterial pressure or heart rate were found between the pre-TEDS and post-TEDS time points ( p = 0.335 and p = 0.846 , respectively). Conclusion. Our findings suggest that TEDS does not have clinically relevant impacts on hemodynamic or vital parameters in critically ill elderly patients. These findings point to the possible safety of TEDS application in this population.

Comparative Study of Safety and Efficacy of Three Different Doses of Fentanyl on Hemodynamic Response to Laryngoscopy and Tracheal Intubation in Patients under General Anaesthesia

Aim of Study: Laryngoscopy and endotracheal intubation are the commonest method for securing a definitive airway for general anaesthesia. It is one of the most invasive and painful stimuli in anaesthesia producing clinically relevant changes in the hemodynamic variables. This study has been designed to compare the safety and efficacy of three different doses of fentanyl (2µg/kg, 3µg/kg and 4µg/kg) in attenuating hemodynamic response, following laryngoscopy and endotracheal intubation. Materials and Methods: In this observational study, three groups of 90 patients belonging to ASA grade I and II, aged between 18 to 65 years, including either gender, posted for elective surgery under GA with informed consent. Baseline vital hemodynamic parameters and the serial heart rate, arterial pressures, SpO2 and respiratory rate were noted at five minutes after intravenous fentanyl administration, during laryngoscopy & intubation and at 1-, 3-, 5-, 10- and 20-minutes after laryngoscopy. Ramsay sedation scores were also noted at five minutes after intravenous fentanyl administration, during extubation and at 10-, 20- and 30-minutes after extubation. Results: There was substantial difference in mean HR, SBP, DBP & MAP values post 5 minutes after intravenous fentanyl administration, during laryngoscopy, at 1, 3-, 5-, 10- and 20-minutes following laryngoscopy and intubation between the three groups. Patients’ behaviour belonging to group C (IV fentanyl 4µg/kg), followed by the patients of group B (IV fentanyl 3µg/kg) presented considerable amount of attenuation of all the hemodynamic stress parameters effectively, with statistically significant results when compared to group A (IV fentanyl 2µg/kg). Conclusion: Intravenous fentanyl 4µg/kg and 3µg/kg are better at attenuating the laryngo-tracheal stress response, in comparison to intravenous fentanyl 2µg/kg.

Comparison of the Effect of Propofol and Dexmedetomidine on Hemodynamic Parameters and Stress Response Hormones During Laparoscopic Cholecystectomy Surgery

Background: General anesthesia induces endocrine, immunologic, and metabolic responses. Anesthetic drugs affect the endocrine system by changing the level of stress hormones and hemodynamic variables of the patient. Objectives: The purpose of this study was to compare the effects of propofol and dexmedetomidine on hemodynamic parameters and stress-induced hormones in laparoscopic cholecystectomy (LC) surgery. Methods: Seventy patients of elective LC were included in this study. The patients were randomly assigned into two equal groups of propofol (75 µg/kg/min) and dexmedetomidine (0.5 µg/kg/hour) as anesthesia maintenance. Hemodynamic parameters (heart rate and mean atrial pressure), blood sugar, and serum epinephrine level were monitored and recorded from pre-anesthesia period to 10 min after entry to post-anesthesia care unit (PACU) according to a planned method. Results: Heart rate and mean atrial pressure changes were significantly lower in dexmedetomidine group in all stages compared to propofol group (P < 0.001). Also, the rises in blood glucose and serum epinephrine levels in the dexmedetomidine group were significantly higher than in the propofol group (P < 0.001). Conclusions: Anesthesia maintenance by dexmedetomidine showed a significant difference in hemodynamic parameters in comparison with propofol. While dexmedetomidine had better effects on controlling hemodynamic parameters, propofol showed better effects on decreasing stress hormones, and it can be suggested for LC surgery.

Hemodynamics Challenges for the Navigation of Medical Microbots for the Treatment of CVDs

Microbots have been considered powerful tools in minimally invasive medicine. In the last few years, the topic has been highly studied by researchers across the globe to further develop the capabilities of microbots in medicine. One of many applications of these devices is performing surgical procedures inside the human circulatory system. It is expected that these microdevices traveling along the microvascular system can remove clots, deliver drugs, or even look for specific cells or regions to diagnose and treat. Although many studies have been published about this subject, the experimental influence of microbot morphology in hemodynamics of specific sites of the human circulatory system is yet to be explored. There are numerical studies already considering some of human physiological conditions, however, experimental validation is vital and demands further investigations. The roles of specific hemodynamic variables, the non-Newtonian behavior of blood and its particulate nature at small scales, the flow disturbances caused by the heart cycle, and the anatomy of certain arteries (i.e., bifurcations and tortuosity of vessels of some regions) in the determination of the dynamic performance of microbots are of paramount importance. This paper presents a critical analysis of the state-of-the-art literature related to pulsatile blood flow around microbots.

Timing Assessment of Response to Fluid Challenge in Patients with Septic Shock

Objectives: Fluid challenge (FC) is most commonly used for fluid responsiveness (FR) evaluation, with a wide divergence in assessment time choices. Therefore, we aimed to explore the optimal assessment time for FC in patients with septic shock. Methods: A prospective cohort study was conducted. Septic shock patients who had experienced initial resuscitation and required an FC with 500 mL 4% gelatin or normal saline (NS) over 5-10 min were included. FR was defined by an increase in cardiac index (CI) >10%. FR and other predefined variables were recorded at baseline (Tb), immediately (T0), and at 10 (T1), 30 (T2), 45 (T3), 60 (T4), 90 (T5), and 120 (T6) min after FC. The incidence of FR and hemodynamic variables at predefined time points were recorded. Data were analyzed by repeated measures of analysis of variance. Results: 63 patients were enrolled, with 43 in the gelatin group and 20 in the NS group. Among the 45/63 (71%) responders, 31 were responded at T0 (ER), while 14 responded at T1 or later (LR). The proportion of NR, ER and LR was comparable between gelatin and NS groups. After FC, the time course of FR status was slightly different between gelatin and NS groups. In the gelatin group, FC induced most responders (69%, 31/45) and frequency of CI maximum (35%, 11/31) at T2 and sustained a positive FR status until T4; while in the NS group, FC induced most responders (55%, 11/20) and frequency of CI maximum (64%, 9/14) at T1, and sustained FR status until T1. Conclusions: Different time courses of FR were found between gelatin and NS group patients undergoing FC. Thus, when NS is used, FR should be performed within 10 min, while it is better to extend the assessment time to 30 min after FC when gelatin is used.