Use of Pleth Variability Index as a Non-invasive, Dynamic Indicator of Left Atrial Pressure Change During MitraClip: Transcatheter Mitral Valve Repair.

BACKGROUND: Transcatheter edge-to-edge repair (TEER) with MitraClip is a safe and effective alternative to surgical mitral valve repair/replacement in patients with high operative risk. Pleth Variability Index (PVI) is a non-invasive, dynamic index based on analysis of the respiratory variations in the plethysmographic waveform recorded transcutaneously by the pulse oximeter. OBJECTIVES: The objective of the study was to evaluate if the hemodynamic effect of improved left-sided output after successful transcatheter mitral valve repair would lead to a significant change in PVI, and if it would correlate with the decrease in left atrial pressure (LAP). DESIGN: Prospective, observational cohort study (ClinicalTrials.gov NCT03993938). SETTING: Single academic hospital in Detroit, Michigan (USA), from October 2019 to February 2021. PARTICIPANTS: The authors included adult patients with severe mitral regurgitation who underwent successful MitraClip placement. MEASUREMENTS AND MAIN RESULTS: Of 30 patients, all components of the LAP (a wave, v wave, and mean) decreased significantly after successful MitraClip placement (P < .01). The median (IQR) PVI increased from 21 (11-35) to 23 (13-38) after clip placement; however, this change was not statistically significant (P = .275). No significant correlation between change in PVI and change in LAP was observed (P = .235). CONCLUSIONS: In patients with severe mitral regurgitation, successful MitraClip resulted in a significant reduction in LAP without a significant change in PVI. A larger sample size may provide more insight on the utility of using PVI as an indicator of LAP change in patients with mitral regurgitation.

The Effect of Sedation on Diagnostic Lumbar Medial Branch Blocks for Facetogenic Low Back Pain: An Observational Study.

BACKGROUND: Lumbar medial branch blocks (MBB) are some of the most commonly performed pain procedures in the United States. Diagnostic MBBs are performed to confirm if the generator of low back pain is the facet joint. However, with diagnostic injections, false positive blocks may occur. OBJECTIVES:   Our prospective observational study aims to investigate the effects of midazolam sedation on patients' perceived intensity of pain relief following lumbar MBB. STUDY DESIGN: This is a single-center multi-site prospective observational study registered on clinicaltrials.gov (NCT04453449). SETTING: The study was approved by the Henry Ford Health System Institutional Review Board (IRB) in June 2020 (IRB# 14010) and registered on clinicaltrials.gov in July 2020 (NCT04453449). This manuscript adheres to the applicable EQUATOR STROBE guidelines for an observational cohort study. METHODS: Patients that underwent MBB without sedation were compared to sedated patients. Patients were asked to complete the Numeric Rating Scale (NRS) at baseline, one day after their diagnostic blocks, as well as 4 weeks and 8 weeks after their lumbar radiofrequency ablation (RFA). The primary outcome is the difference between baseline NRS pain scores and the lowest reported score in the 8 hours following MBB. For patients who proceed to RFA, the frequency of false positive blocks was evaluated. A patient was considered to have a false positive block when they failed to achieve 50% pain relief from RFA after 2 successful sequential MBBs. RESULTS: There was no significant difference in the NRS pain score change between the sedated and non-sedated groups for diagnostic block one (P = 0.167) and diagnostic block 2 (P = 0.6145). There was no significant difference of false positive rates between non-sedation and sedation patients at 4-weeks post-RFA (P = 0.7178) and at 8-weeks post-RFA (P = 1.000). LIMITATIONS: Some of the limitations of this study include its nonrandomized design, patient self-reported pain scores, as well as the small variability in the injection technique of proceduralists and in the anatomical location of the injection site. CONCLUSIONS: This study showed that midazolam did not change patients' perceived intensity of pain following MBB, as well as false positive rates after RFA. Larger studies are required to draw definitive conclusions.

CON: Pulmonary artery catheter use should be forgone in modern clinical practice.

The pulmonary artery catheter (PAC) and its role in the practice of modern medicine remains to be questioned and has experienced a substantial decline in its use in the most recent decades. The complications associated to its use, the lack of consistency of the interpretation provided by the PAC among clinicians, the development of new hemodynamic methods, and the deleterious cost profile associated to the PAC are some of the reasons behind the decrease in its use. Since its introduction into clinical practice, the PAC and the data obtained from its use became paramount in the management of critically ill patients as well as for the high-risk/invasive procedures. Initially, many clinicians were under the impression that regardless the clinical setting, acquiring the information provided by the PAC justified its use, until a growing body of evidence demonstrated its lack of mortality and morbidity improvement, as well as several reports of the presence of difficulties-some of them fatal-during its insertion. The authors present an updated review discussing the futility of the PAC in current clinical practice, the complications associated to its insertion, the lack of mortality benefit in critically ill patients and cardiac surgery, as well as present alternative hemodynamic methods to the PAC.

Comparison of Deep Sedation and General Anesthesia With an Endotracheal Tube for Transcaval Transcatheter Aortic Valve Replacement: A Pioneering Institution's Experience.

OBJECTIVES: Transcaval transcatheter aortic valve replacement (TC-TAVR) is an alternative approach to transcatheter aortic valve replacement involving deployment of the bioprosthetic valve via a conduit created from the inferior vena cava to the descending aorta in patients for whom the traditional transfemoral approach is not feasible. By analyzing the largest known cohort of TC-TAVR patients, the authors wished to compare hospital length of stay and post-procedure outcomes between patients who underwent the procedure under deep sedation (DS) and patients who underwent general anesthesia with an endotracheal tube. DESIGN: Retrospective, single-center study. SETTING: Henry Ford Hospital in Detroit, MI. PARTICIPANTS: Patients undergoing TC-TAVR from 2015 to 2018. MEASUREMENTS AND MAIN RESULTS: Seventy-nine patients were included in the analysis, which consisted of 38 under general anesthesia with an endotracheal tube and 41 under DS. The sample was divided into a general anesthesia (GA) group and DS group. There were no significant differences in implant success rate or post-procedure outcomes, including in-hospital mortality (p = 0.999) and major vascular complication rate (p = 0.481), between the two groups. Patients in the GA group stayed a median of 24 hours longer in the intensive care unit (ICU) (p < 0.001) and one day longer in the hospital (p = 0.046) after the procedure compared to patients in the DS group. The median procedure time was significantly lower (135 minutes) in the DS group compared to the GA group (167 minutes, p < 0.001). CONCLUSIONS: Patients undergoing TC-TAVR under DS had similar postoperative outcomes and shorter post-procedure hospital and ICU lengths of stay compared to general anesthesia. In the authors' experience, DS is the preferred anesthetic technique for TC-TAVR.

Increased metabolic activity of neutrophils in patients with chronic obstructive pulmonary disease.

AIMS: To compare the metabolic activity of peripheral neutrophils in patients diagnosed with chronic obstructive pulmonary disease (COPD) with that of healthy, nonsmoking volunteers. MATERIALS AND METHODS: Venous blood samples were taken from patients diagnosed with COPD as well as from healthy nonsmokers. Each sample was subjected to the nitro blue tetrazolium (NBT) test in which neutrophils exhibiting elevated metabolic activity were detected by light microscopy. The test was repeated after stimulation with Escherichia coli (E. coli) endotoxin with fresh samples. Neutrophils showing dye uptake were then counted in each case. RESULTS: We found that the mean numbers of activated neutrophils without and with the addition of endotoxin were 19% and 23%, respectively, in the control group and 56% and 62%, respectively, in the test group. Two-sample t-test statistic revealed that there was a significant (P < 0.01) increase in neutrophilic metabolic activity in patients with COPD as compared to that in healthy volunteers. This significance remained even after stimulation using E. coli endotoxin. CONCLUSION: The results hint at a potentially relevant pathogenic mechanism in COPD related to the metabolic activity of neutrophils. By exhibiting enhanced metabolic activity, neutrophils in the COPD patients are more likely to be involved in damaging lung tissues.