Efficacy and safety of endotracheal instillation of iloprost for persistent pulmonary hypertension of the newborn

Objective: To determine the efficacy and safety of endotracheal instillation of iloprost as a rescue therapy for persistent pulmonary hypertension of the newborn. Methods: Neonates diagnosed with persistent pulmonary hypertension who were unresponsive to standard treatment protocol applied for persistent pulmonary hypertension in our unit, and who were being followed up with mechanical ventilation, were included in the study. Iloprost was instilled endotracheally as a rescue treatment. Systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, fraction of inspired oxygen, preductal and postductal venous oxygen saturation, heart rate, and blood pressure were recorded before and after 30 minutes of endotracheal iloprost instillation. Adverse events after endotracheal iloprost were recorded. Results: Twenty neonates were included. The median gestational age and birth weight were found to be 37 (30.5-38) weeks and 2975 (2125-3437.5) grams, respectively. When compared to the period before endotracheal iloprost instillation, systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, and fraction of inspired oxygen values significantly decreased (p < 0.001, p < 0.001, p = 0.021, p = 0.001, respectively), whereas preductal and postductal oxygen saturation values significantly increased 30 minutes after the endotracheal iloprost instillation (p = 0.002, p < 0.001, respectively). There were no significant differences in heart rate and blood pressure values before and after the iloprost administration. No adverse events were observed. Conclusion: Endotracheal instillation of iloprost was found to be an effective and safe therapy for persistent pulmonary hypertension unresponsive to conventional treatment.

Heart-Protective Mechanical Ventilation in Postoperative Cardiosurgical Patients

Background. This study compared the hemodynamic effects and gas exchange under several different ventilator settings—with regard to tidal volume, respiratory rate, and end-expiratory pressure—in patients after coronary artery bypass grafting (CABG). Methods. Prospective interventional cohort study with a controlled group in a single cardiosurgical ICU involving 119 patients following on-pump CABG surgery. During the 1st postoperative hour, the intervention group patients were ventilated with Vt 10 ml × kg−1, RR 14/min, PEEP 5 cmH2O (“conventional ventilation”). During the 2nd hour, RR was reduced to 8/min (“reduced RR ventilation”). At 3 hrs, Vt was decreased to 6 ml × kg−1, RR returned to 14/min, and PEEP increased to 10 cmH2O (“low Vt-high PEEP ventilation”). Results. Patients in the “low Vt-high PEEP” ventilation period showed significantly lower alveolar ventilation and thoraco-pulmonary compliance than during “reduced RR” ventilation. Mean airway pressure and Vds/Vt peaked during low Vt-high PEEP ventilation; however, driving pressure was lower. Vt decrease and PEEP increase did not lead to oxygenation improvement and worsened CO2 elimination. Hemodynamically, the study revealed significant cardiac output decrease during low Vt-high PEEP ventilation. In 23.2% of patients, catecholamine therapy was initiated. Conclusions. In postoperative cardiosurgical patients, MV with Vt 6 ml × kg−1 and PEEP 10 cm H2O is characterized by worsened oxygenation and elimination of CO2 and a less favorable hemodynamic profile than ventilation with Vt 10 ml × kg−1 and PEEP 5 cmH2O. New and Noteworthy. (i) Patients after CABG may be especially sensitive to low tidal volume and increased PEEP as it negatively affects hemodynamic profile by means of the right heart preload decrease and afterload increase. (ii) Mechanical ventilation settings aiming to minimize mean airway pressure reduce the negative effects of positive inspiratory pressure and are favorable for hemodynamics.

Effects of Inhaled Iloprost for the Management of Persistent Pulmonary Hypertension of the Newborn

Objective The study aimed to evaluate the effects of inhaled iloprost on oxygenation indices in neonates with persistent pulmonary hypertension of the newborn (PPHN). Study Design We conducted a retrospective chart review of 30 patients with PPHN from January 2014 to November 2018, who did not respond to inhaled nitric oxide (iNO) alone and received inhaled iloprost. Twenty-two patients met the inclusion criteria and eight patients were excluded from the study (complex cardiac disease and extreme prematurity). Patients were categorized as responders or nonresponders (patients who required extracorporeal membrane oxygenation or died). Oxygenation index, mean airway pressure (MAP), and arterial partial pressure of oxygen (PaO2) were recorded. Results Among a total of 22 patients who were included in the study, 10 were classified as nonresponders as they required either extracorporeal membrane oxygenation or died. Gestational age and gender did not differ between responders and nonresponders. The median PaO2 was lower (37 vs. 42 mm Hg; p < 0.05) and median MAP was higher (20 vs. 17 cm H2O; p < 0.02) in nonresponders compared with responders just prior to initiating iloprost. Iloprost responders had a significant increase in median PaO2 and decrease in median oxygenation index in the 24 hours after initiating treatment (p < 0.05), with no significant change in required mean airway pressure over that same period. There was no change in vasopressor use or clinically significant worsening of platelets count, liver, and kidney functions after initiating iloprost. Conclusion Inhaled iloprost is well tolerated and seems to have beneficial effects in improving oxygenation indices in neonates with PPHN who do not respond to iNO. There is a need of well-designed prospective trials to further ascertain the benefits of using inhaled iloprost as an adjunct treatment in neonates with PPHN who do not respond to iNO alone. Key Points

Lung Protective Ventilation in Brain-Injured Patients: Low Tidal Volumes or Airway Pressure Release Ventilation?

The optimal mode of mechanical ventilation for lung protection is unknown in brain-injured patients as this population is excluded from large studies of lung protective mechanical ventilation. Survey results suggest that low tidal volume (LTV) ventilation is the favored mode likely due to the success of LTV in other patient populations. Airway pressure release ventilation (APRV) is an alternative mode of mechanical ventilation that may offer several benefits over LTV in this patient population. APRV is an inverse-ratio, pressure-controlled mode of mechanical ventilation that utilizes a higher mean airway pressure compared with LTV. This narrative review compares both modes of mechanical ventilation and their consequences in brain-injured patients. Fears that APRV may raise intracranial pressure by virtue of a higher mean airway pressure are not substantiated by the available evidence. Primarily by virtue of spontaneous breathing, APRV often results in improvement in systemic hemodynamics and thereby improvement in cerebral perfusion pressure. Compared with LTV, sedation requirements are lessened by APRV allowing for more accurate neuromonitoring. APRV also uses an open loop system supporting clearance of secretions throughout the respiratory cycle. Additionally, APRV avoids hypercapnic acidosis and oxygen toxicity that may be especially deleterious to the injured brain. Although high-level evidence is lacking that one mode of mechanical ventilation is superior to another in brain-injured patients, several aspects of APRV make it an appealing mode for select brain-injured patients.

Airway Pressure and Respiratory Mechanics Variability with Different Body Positions in Mechanically Ventilated Critical Care Patients: A Prospective Comparative Clinical Study

Aim: This prospective comparative study aimed to investigate the effect of various body positions on changes of respiratory parameters mostly; the TV, oxygen saturation, airway pressure, and endotracheal tube cuff pressure in mechanically ventilated critical care patients. Background: Many patients who are admitted to the critical care unit require intubation and invasive mechanical ventilation for many reasons such as major trauma, medical causes, or post-operative major surgeries. Changing a patient’s position in the critical care unit is very important for the following benefits; to break through the routine monotonic delivery of mechanical ventilation, to favor the clearance of respiratory secretions, the prevention of pressure sores and ventilator acquired pneumonia, and finally the improvement in lung volume and oxygenation. Methods: A prospective, comparative study was carried out on 210 patients of both gender, aged between 21-70 years old admitted to ICU due to many reasons. After stabilization of patient condition and connection of monitors’ cables, supine position or semi setting position was chosen and this was documented in the patient’s chart. All patients were sedated to prevent them from breathing against the machine which causes the ETT cuff pressure and mean airway pressure to rise. Fentanyl sedation drug (Loading dose: 1–2 mic/kg/hour infused gradually. Maintenance dose: 1-4 mic/kg/hour) using continuous intravenous infusion typically in combination with Midazolam sedation (0.05-0.2 mg/kg/hour). The following parameters were recorded; tidal volume, mean airway pressure, PO2 /FIO2 , and ETT cuff pressure. Results: Our results show that about (58.1%) were male and (41.9%) were female. Concerning age, their mean was between (40.6 ± 8.9) years. Regarding diagnosis (50.5%) of patients were admitted with major trauma, (31.9%) due to medical causes, and (17.6%) admitted due to major chest and abdominal surgeries. The patient’s mean heart rate was (93.6 ± 7.5) b/m and the Mean Arterial Pressure was (67.7 ± 0.6)°C. Tables the Description, SOP2, Mean airway, and ETT cuff pressure of each body position in the study with the highest SPO2 98% and cuff pressure 19.2+41 in the prone position. The position checklist is illustrated in Table and Figure. The highest TV (520 ml) and PO2 /FIO2 ratio (410) were in prone poison and the lowest was in Lower Fowler position (460 ml and 320) respectively. Regarding outcome and ICU stay which were the best in both semi setting and prone position. Conclusion: Supine position (lying flat) or lateral position do not seem beneficial for critically ill patients in terms of respiratory mechanics. The semi-sitting position (with thorax angulation=30° from the horizontal plane) is associated with improvement of PO2/FIO2 , oxygenation, and tidal volume, and the effects of prone position on respiratory mechanics are very beneficial and this reflected on patient outcome and short ICU length of stay.

Bronchial blocker versus double-lumen endobronchial tube in minimally invasive cardiac surgery

Background To compare the therapeutic value of a bronchial blocker (BB) with a double-lumen tube (DLT) in minimally invasive cardiac surgery (MICS). Methods Sixty patients who underwent MICS were randomized to use either a DLT (Group D, n = 30) or a BB (Group B, n = 29; one failed was omitted). The following data were collected: time of intubation and tube localization; incidence of tube displacement; postoperative sore throat and hoarseness; time of cardiopulmonary bypass; maintenance time for SpO2 < 90% (PaCO2 < 60 mmHg); mean arterial pressure and heart rate; SpO2, PaO2, PaCO2, EtCO2, mean airway pressure, and airway peak pressure; surgeons’ satisfaction with anesthesia; and short-term complications. Results The times of intubation and tube localization were significantly longer in Group B than in Group D (P < 0.05). Patients in Group B exhibited significantly lower incidence of tube displacement, postoperative sore throat, and hoarseness when compared with patients in Group D (P < 0.05). Mean arterial pressure and heart rate were significantly lower in Group B than in Group D after tracheal intubation (P < 0.05). The mean airway pressure and airway peak pressure were significantly lower in Group B than in Group D after one-lung ventilation (P < 0.05). SpO2 and PaO2 in Group B were significantly higher than in group D after cardiopulmonary bypass (P < 0.05). No short-term postoperative complications were observed in patients of Groups B and D during 3 month follow-up. Conclusion BB can be a potential alternative to the conventional DLT for lung isolation in MICS. Trial registration: ChiCTR1900024250, July 2, 2019.