Extracorporeal Membrane Oxygenation with Right Ventricular Assist Device for COVID-19 ARDS.

BACKGROUND: Right ventricular failure is an underrecognized consequence of COVID-19 pneumonia. Those with severe disease are treated with extracorporeal membrane oxygenation (ECMO) but with poor outcomes. Concomitant right ventricular assist device (RVAD) may be beneficial. METHODS: A retrospective analysis of intensive care unit patients admitted with COVID-19 ARDS (Acute Respiratory Distress Syndrome) was performed. Nonintubated patients, those with acute kidney injury, and age > 75 were excluded. Patients who underwent RVAD/ECMO support were compared with those managed via invasive mechanical ventilation (IMV) alone. The primary outcome was in-hospital mortality. Secondary outcomes included 30-d mortality, acute kidney injury, length of ICU stay, and duration of mechanical ventilation. RESULTS: A total of 145 patients were admitted to the ICU with COVID-19. Thirty-nine patients met inclusion criteria. Of these, 21 received IMV, and 18 received RVAD/ECMO. In-hospital (52.4 versus 11.1%, P = 0.008) and 30-d mortality (42.9 versus 5.6%, P= 0.011) were significantly lower in patients treated with RVAD/ECMO. Acute kidney injury occurred in 15 (71.4%) patients in the IMV group and zero RVAD/ECMO patients (P< 0.001). ICU (11.5 versus 21 d, P= 0.067) and hospital (14 versus 25.5 d, P = 0.054) length of stay were not significantly different. There were no RVAD/ECMO device complications. The duration of mechanical ventilation was not significantly different (10 versus 5 d, P = 0.44). CONCLUSIONS: RVAD support at the time of ECMO initiation resulted in the no secondary end-organ damage and higher in-hospital and 30-d survival versus IMV in specially selected patients with severe COVID-19 ARDS. Management of severe COVID-19 ARDS should prioritize right ventricular support.

A comparison between the Supreme laryngeal mask airway and the laryngeal tube suction during spontaneous ventilation: A randomized prospective study.

BACKGROUND AND AIMS: The Supreme laryngeal mask airway (SLMA) and the laryngeal tube suction-disposable (LTS-D), both second-generation supraglottic airway devices, have a record of efficiency when used for airway management in mechanically ventilated patients, during general anesthesia. There is no published data comparing these two devices in patients breathing spontaneously during general anesthesia. MATERIAL AND METHODS: Eighty patients with normal airways undergoing elective general anesthesia with spontaneous ventilation were randomized to airway management with a SLMA or LTS-D. Efficacy and adequacy of oxygenation and ventilation were compared. RESULTS: No cases of desaturation of oxygen saturation (SpO2) values of less than 95% occurred with either device. The mean difference for SpO2 between the two devices (0.7%) has no clinical significance. Slight hypercapnia was noted with both devices to acceptable values during spontaneous ventilation. CONCLUSIONS: Both SLMA and LTS-D are suitable and effective for airway management in patients breathing spontaneously during general anesthesia for minor surgery of short duration.

The prediction of difficult intubation in obese patients using mirror indirect laryngoscopy: A prospective pilot study.

BACKGROUND: The incidence of difficult laryngoscopy and intubation in obese patients is higher than in the general population. Classical predictors of difficult laryngoscopy and intubation have been shown to be unreliable. We prospectively evaluated indirect mirror laryngoscopy as a predictor of difficult laryngoscopy in obese patients. MATERIALS AND METHODS: 60 patients with a body mass index (BMI) greater than 30, scheduled to undergo general anesthesia, were enrolled. Indirect mirror laryngoscopy was performed and was graded 1-4 according to Cormack and Lehane. A view of grade 3-4 was classified as predicting difficult laryngoscopy. Additional assessments for comparison were the Samsoon and Young modification of the Mallampati airway classification, Wilson Risk Sum Score, neck circumference, and BMI. The view obtained upon direct laryngoscopy after induction of general anesthesia was classified according to Cormack and Lehane as grade 1-4. RESULTS: Sixty patients met the inclusion criteria; however, 8 (13.3%) patients had an excessive gag reflex, and examination of the larynx was not possible. 15.4% of patients who underwent direct laryngoscopy had a Cormack and Lehane grade 3 or 4 view and were classified as difficult. Mirror laryngoscopy had a tendency toward statistical significance in predicting difficult laryngoscopy in these patients. CONCLUSIONS: This study is consistent with previous studies, which have demonstrated that no one individual traditional test has proven to be adequate in predicting difficult airways in the obese population. However, the new application of an old test - indirect mirror laryngoscopy - could be a useful additional test to predict difficult laryngoscopy in obese patients.

Use of a third-generation perfluorocarbon for preservation of rat DCD liver grafts.

BACKGROUND: Cold storage in any of the commonly used preservation solutions is not always adequate for donation after cardiac death (DCD) liver grafts due to prolonged warm ischemic time. In this study, we used a third-generation perfluorocarbon (PFC), Oxycyte, for DCD liver graft preservation in a rat model. MATERIALS AND METHODS: Twenty-eight rats (14 in each group) were used. Thirty minutes after cardiopulmonary arrest, livers were harvested and flushed with a cold and pre-oxygenated solution of either University of Wisconsin (UW) or UW + 20% PFC. After 8 h of cold preservation in either of the investigated solutions, liver graft specimens were analyzed for evidence of ischemic injury. Hemotoxylin and eosin staining (H and E), as well as immunohistochemical analysis with anti-cleaved caspase 3 antibody, was performed. Levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the preservation solution were analyzed at 1 and 8 h during preservation. RESULTS: In the PFC group, the degree of cell congestion, vacuolization and necrosis were all significantly less than in the UW group (P = 0.002-0.004). The number of cells with a positive cleaved caspase 3 antibody reaction was reduced by about 50% in comparison with the UW group (P < 0.006). The AST level in the PFC group was significantly less than in the UW group after 8 h of preservation (P < 0.048). CONCLUSION: The addition of PFC to UW solution significantly decreases the degree of histologic damage in rat DCD liver grafts. This preservation strategy can be potentially helpful for organ preservation after prolonged warm ischemia.

Transesophageal echocardiographic and oxymetric evidence of intraoperative reversal of flow through a patent foramen ovale during an off-pump coronary artery bypass grafting.

Mechanical stabilization of target coronary arteries in the beating heart has facilitated the practice of "off-pump" coronary artery bypass grafting. Exposing the target coronary artery for stabilization involves maneuvers that frequently cause hemodynamic alterations including decreased cardiac output and increased pulmonary artery and/or central venous pressures (CVP). The presence of a patent foramen ovale (PFO) in the setting of increased CVP may produce a right-to-left shunt through the PFO. We report a case of a patient undergoing off-pump coronary artery bypass grafting with a PFO with a left to right atrium shunt flow of 307 mL/min. During manipulation and elevation of the heart to expose the target vessel, the CVP increased from 15 to 30 mm Hg and the shunt through the PFO reversed direction, going from right to left atrium with a flow of 161 mL/min. Mixed venous oxygen saturation and the calculated shunt fraction decreased from 84% to 78% and 14% to 10%, respectively. All parameters returned to normal after the heart was lowered back inside the chest.

Central neuraxial analgesia in cardiac surgery.

An ideal anesthetic for cardiac surgery should provide intraoperative cardiovascular stability and a stable and pain-free recovery. High-dose narcotics, whether given as an initial bolus or by the continuous infusion method, certainly have brought current practice closer to this ideal. Central neuraxial analgesia is an alternative to high-dose narcotics, but its use has long been an issue of debate and concern in cardiac surgery. The need for full heparinization for cardiopulmonary bypass has curtailed the use of central neuraxial blocks. Until fairly recently, very few centers dared to attempt this kind of effective analgesia in cardiac surgery. However, during the last few years more and more reports have been published on the efficacy and safety of this type of analgesia when appropriate precautions are taken. The objective of this report is to examine some of these issues.

Comparison of arterial systolic pressure variation with other clinical parameters to predict the response to fluid challenges during cardiac surgery.

Prophylactic optimization of stroke volume during surgery has been thought by some to reduce complications following surgery. Mechanical ventilation has been shown to induce variations in systolic systemic arterial blood pressure. Measuring such variations in systolic pressure (SPV) might serve as an attractive method for guiding fluid therapy intraoperatively. It is unknown if variations in systolic pressure following the rapid intravenous administration of a specific volume of fluid would lead to changes in pressure measurements obtained from a pulmonary artery with sufficient sensitivity to predict or guide the need for expansion of the intravascular volume to optimize stroke volume as an index of cardiac function. The purpose of this study was to determine if such measurements of changes in systolic pressures would be useful in optimizing stroke volume. Nineteen patients undergoing cardiac surgery were enrolled in a prospective cohort study. Following induction of general anesthesia, one or more 250 mL boluses of 6% hetastarch were administered. Stroke volume was calculated from the cardiac output obtained by thermodilution using a pulmonary artery catheter. If the patient s stroke volume increased by less than 10% as a result of a given fluid challenge, the patient was classified as a non-responder. However, if the stroke volume increased by more than 10%, the patient was classified as a responder. The variations in systolic pressure and echocardiographic indices were simultaneously measured before and after the administration of each 250 mL fluid bolus. Pulmonary artery occlusion pressure (PAOP) values were significantly lower in patients who responded to fluid boluses (p=0.0085) than in those who did not. Similarly SPV and SPVdown values (defined as the decrease in systolic pressure with ventilation) were significantly greater in the responders (p<0.05). No significant intergroup differences were observed in SPVup (increase in systolic pressure with ventilation) or echocardiographic-derived left ventricular end diastolic area. A PAOP value less than 10 mm Hg predicted a response (sensitivity 68%, specificity 79%). Although significant intergroup differences in the extent of systolic pressure variations were observed, no appropriate threshold values could be determined that would accurately predict the response to a fluid bolus. There is a relationship between SPV and SPVdown values and intravascular volume status. SPV and echocardiographic-derived values did not predict the response to a fluid bolus as well as values obtained from the pulmonary artery catheter.

Bloqueos del neuroeje en cirugía cardíaca / Central neuroaxial blocks in cardiac surgery

El anestésico ideal para la cirugía cardíaca debe ofrecer, además de estabilidad hemodinámica intraoperatoria, una recuperación postanestésica libre de dolor. La utilización de narcóticos en altas dosis se acerca a este ideal. Los bloqueos del neuroeje son una alternativa a los narcóticos en altas dosis. La efectividad de la morfina por vía intratecal o de la analgesia epidural torácica para controlar el dolor postoperatorio está demostrada más allá de toda duda. Esta analgesia es muy necesaria no sólo para confort del paciente sino por una multitud de factores; entre ellos, para disminuir la frecuencia y la severidad de episodios isquémicos postoperatorios así como la cantidad de complicaciones pulmonares y la utilización de drogas vasodilatadoras en el postoperatorio inmediato. El principal problema asociado al uso de morfina por vía intratecal es la depresión respiratoria, que tiene una incidencia de entre el 0.36 y el 1.9 por ciento. Esta depresión está relacionada con la dosis y es fácilmente tratada con naloxona sin abolir el efecto analgésico. Administrar morfina por vía intratecal es técnicamente más fácil y menos costoso, pero la analgesia epidural torácica se puede usar por varios días, no se necesita utilizar opioides, y, al emplearse anestésicos locales, tiene efectos muy beneficiosos sobre la circulación coronaria. La posibilidad de hematoma espinal es cierta y ha impedido la utilización de estos bloqueos, pero ha habido numerosos reportes acerca del uso de morfina por vía intratecal o analgesia epidural torácica involucrando miles de pacientes sin consecuencias adversas. Algunas precauciones son necesarias: agujas ultrafinas, no más de dos intentos para la morfina por vía intratecal y colocación del catéter epidural 20 horas antes de la operación. La utilización de morfina por vía intratecal o analgesia epidural torácica le da grandes beneficios a los pacientes en términos de disminución de complicaciones cardíacas y pulmonares. El riesgo potencial de un hematoma espinal es real, pero probablemente muy sobreestimado, y requiere más estudio.

Bloqueos del neuroeje en cirugía cardíaca / Central neuroaxial blocks in cardiac surgery

El anestésico ideal para la cirugía cardíaca debe ofrecer, además de estabilidad hemodinámica intraoperatoria, una recuperación postanestésica libre de dolor. La utilización de narcóticos en altas dosis se acerca a este ideal. Los bloqueos del neuroeje son una alternativa a los narcóticos en altas dosis. La efectividad de la morfina por vía intratecal o de la analgesia epidural torácica para controlar el dolor postoperatorio está demostrada más allá de toda duda. Esta analgesia es muy necesaria no sólo para confort del paciente sino por una multitud de factores; entre ellos, para disminuir la frecuencia y la severidad de episodios isquémicos postoperatorios así como la cantidad de complicaciones pulmonares y la utilización de drogas vasodilatadoras en el postoperatorio inmediato. El principal problema asociado al uso de morfina por vía intratecal es la depresión respiratoria, que tiene una incidencia de entre el 0.36 y el 1.9 por ciento. Esta depresión está relacionada con la dosis y es fácilmente tratada con naloxona sin abolir el efecto analgésico. Administrar morfina por vía intratecal es técnicamente más fácil y menos costoso, pero la analgesia epidural torácica se puede usar por varios días, no se necesita utilizar opioides, y, al emplearse anestésicos locales, tiene efectos muy beneficiosos sobre la circulación coronaria. La posibilidad de hematoma espinal es cierta y ha impedido la utilización de estos bloqueos, pero ha habido numerosos reportes acerca del uso de morfina por vía intratecal o analgesia epidural torácica involucrando miles de pacientes sin consecuencias adversas. Algunas precauciones son necesarias: agujas ultrafinas, no más de dos intentos para la morfina por vía intratecal y colocación del catéter epidural 20 horas antes de la operación. La utilización de morfina por vía intratecal o analgesia epidural torácica le da grandes beneficios a los pacientes en términos de disminución de complicaciones cardíacas y pulmonares. El riesgo potencial de un hematoma espinal es real, pero probablemente muy sobreestimado, y requiere más estudio. (AU)