ABSTRACT
BACKGROUND: Severe lung disease frequently presents with both refractory hypoxemia and right ventricular (RV) failure. Right ventricular assist device with an oxygenator (OxyRVAD) is an extracorporeal membrane oxygenation (ECMO) configuration of RV bypass that also supplements gas exchange. This systematic review summarises the available literature regarding the use of OxyRVAD in the setting of severe lung disease with associated RV failure. METHODS: PubMed, Embase, and Google Scholar were queried on September 27, 2023, for articles describing the use of an OxyRVAD configuration. The main outcome of interest was survival to intensive care unit (ICU) discharge. Data on the duration of OxyRVAD support and device-related complications were also recorded. RESULTS: Out of 475 identified articles, 33 were retained for analysis. Twenty-one articles were case reports, and 12 were case series, representing a total of 103 patients. No article provided a comparison group. Most patients (76.4%) were moved to OxyRVAD from another type of mechanical support. OxyRVAD was used as a bridge to transplant or curative surgery in 37.4% and as a bridge to recovery or decision in 62.6%. Thirty-one patients (30.1%) were managed with the dedicated single-access dual-lumen ProtekDuo cannula. Median time on OxyRVAD was 12 days (interquartile range 8-23 days), and survival to ICU discharge was 63.9%. Device-related complications were infrequently reported. CONCLUSION: OxyRVAD support is a promising alternative for RV support when gas exchange is compromised, with good ICU survival in selected cases. Comparative analyses in patients with RV failure with and without severe lung disease are needed.
ABSTRACT
BACKGROUND: In patient requiring vasopressors, the radial artery pressure may underestimate the true central aortic pressure leading to unnecessary interventions. When using a femoral and a radial arterial line, this femoral-to-radial arterial pressure gradient (FR-APG) can be detected. Our main objective was to assess the accuracy of non-invasive blood pressure (NIBP) measures; specifically, measuring the gradient between the NIBP obtained at the brachial artery and the radial artery pressure and calculating the non-invasive brachial-to-radial arterial pressure gradient (NIBR-APG) to detect an FR-APG. The secondary objective was to assess the prevalence of the FR-APG in a targeted sample of critically ill patients. METHODS: Adult patients in an intensive care unit requiring vasopressors and instrumented with a femoral and a radial artery line were selected. We recorded invasive radial and femoral arterial pressure, and brachial NIBP. Measurements were repeated each hour for 2 h. A significant FR-APG (our reference standard) was defined by either a mean arterial pressure (MAP) difference of more than 10 mmHg or a systolic arterial pressure (SAP) difference of more than 25 mmHg. The diagnostic accuracy of the NIBR-APG (our index test) to detect a significant FR-APG was estimated and the prevalence of an FR-APG was measured and correlated with the NIBR-APG. RESULTS: Eighty-one patients aged 68 [IQR 58-75] years and an SAPS2 score of 35 (SD 7) were included from which 228 measurements were obtained. A significant FR-APG occurred in 15 patients with a prevalence of 18.5% [95%CI 10.8-28.7%]. Diabetes was significantly associated with a significant FR-APG. The use of a 11 mmHg difference in MAP between the NIBP at the brachial artery and the MAP of the radial artery led to a specificity of 92% [67; 100], a sensitivity of 100% [95%CI 83; 100] and an AUC ROC of 0.93 [95%CI 0.81-0.99] to detect a significant FR-APG. SAP and MAP FR-APG correlated with SAP (r2 = 0.36; p < 0.001) and MAP (r2 = 0.34; p < 0.001) NIBR-APG. CONCLUSION: NIBR-APG assessment can be used to detect a significant FR-APG which occur in one in every five critically ill patients requiring vasoactive agents.
ABSTRACT
BACKGROUND: Little is known about the potentiating effect of propofol on neuromuscular blocking drugs. However, some animal studies indicate a dose-dependent increase of the potency of neuromuscular blocking drugs by propofol. This study compared mivacurium potency after five minutes and after 20 min of total intravenous anesthesia with propofol (TIVA propofol). METHODS: Twenty-eight patients were randomized into two groups, after approval of the Ethics Committee and written consent. Anesthesia was induced, in all patients, using remifentanil 0.5 microg.kg(-1).min(-1) for two minutes, after which: 3 mg.kg(-1) of propofol was injected; a laryngeal mask airway was inserted; and intermittent, positive pressure ventilation was initiated. Anesthesia was maintained using TIVA propofol (titrated using bispectral index monitoring to 40-45). Neuromuscular monitoring consisted of phonomyography at the adductor pollicis muscle. In Groups 5 min and 20 min, a tetanic stimulation of the ulnar nerve commenced after four minutes and after 19 min of TIVA, respectively, followed by controlled, single twitch stimulation at 1 Hz for one minute. Boli of 60, 30, 30, and 30 microg.kg(-1) mivacurium, respectively, were administered (each drug increment was administered after the effect of the previous dose had caused a stable response), and single twitch stimulation continued at 0.1 Hz. The dose-response curve was determined for both groups; potency was calculated using log-probit analysis. Data were presented as mean (SD) and were compared using two-sided analysis of variance, P < 0.05. RESULTS: Patient characteristics were similar in the two groups. The corresponding ED(50) and ED(95) values were greater, at 76.7 +/- 12.4 microg.kg(-1) and 146.6 +/- 27.6 microg.kg(-1) for Group 5 min, vs 46.7 +/- 12.2 microg.kg(-1) and 101.1 +/- 20.2 microg.kg(-1) for Group 20 min, respectively. CONCLUSIONS: After 20 min of TIVA propofol, the potency of mivacurium is approximately 50% greater than after five minutes of TIVA propofol. For clinical purposes, it is important, therefore, to consider the duration of TIVA propofol before determining the dose of neuromuscular blocking drug.
