Pasquale Raimondo

Physiological Effects of the Open Lung Approach in Patients with Early, Mild, Diffuse Acute Respiratory Distress Syndrome: An Electrical Impedance Tomography Study.

Background: To test the hypothesis that in early, mild, acute respiratory distress syndrome (ARDS) patients with diffuse loss of aeration, the application of the open lung approach (OLA) would improve homogeneity in lung aeration and lung mechanics, without affecting hemodynamics. Methods: Patients were ventilated according to the ARDS Network protocol at baseline (pre-OLA). OLA consisted in a recruitment maneuver followed by a decremental positive end-expiratory pressure trial. Respiratory mechanics, gas exchange, electrical impedance tomography (EIT), cardiac index, and stroke volume variation were measured at baseline and 20 min after OLA implementation (post-OLA). Esophageal pressure was used for lung and chest wall elastance partitioning. The tomographic lung image obtained at the fifth intercostal space by EIT was divided in two ventral and two dorsal regions of interest (ROIventral and ROIDorsal). Results: Fifteen consecutive patients were studied. The OLA increased arterial oxygen partial pressure/inspired oxygen fraction from 216 ± 13 to 311 ± 19 mmHg (P < 0.001) and decreased elastance of the respiratory system from 29.4 ± 3 cm H2O/l to 23.6 ± 1.7 cm H2O/l (P < 0.01). The driving pressure (airway opening plateau pressure − total positive end-expiratory pressure) decreased from 17.9 ± 1.5 cm H2O pre-OLA to 15.4 ± 2.1 post-OLA (P < 0.05). The tidal volume fraction reaching the dorsal ROIs increased, and consequently the ROIVentral/Dorsal impedance tidal variation decreased from 2.01 ± 0.36 to 1.19 ± 0.1 (P < 0.01). Conclusions: The OLA decreases the driving pressure and improves the oxygenation and lung mechanics in patients with early, mild, diffuse ARDS. EIT is useful to assess the impact of OLA on regional tidal volume distribution.

Effect of age on the performance of bispectral and entropy indices during sevoflurane pediatric anesthesia: a pharmacometric study.

Bispectral index (BIS) and entropy monitors have been proposed for use in children, but research has not supported their validity for infants. However, effective monitoring of young children may be even more important than for adults, to aid appropriate anesthetic dosing and reduce the chance of adverse consequences. This prospective study aimed to investigate the relationships between age and the predictive performance of BIS and entropy monitors in measuring the anesthetic drug effects within a pediatric surgery setting.

Effects of Nebulizer Position, Gas Flow, and CPAP on Aerosol Bronchodilator Delivery: An In Vitro Study

BACKGROUND: The aim of this study was to investigate the effects of different delivery circuit configurations, nebulizer positions, CPAP levels, and gas flow on the amount of aerosol bronchodilator delivered during simulated spontaneous breathing in an in vitro model. METHODS: A pneumatic lung simulator was connected to 5 different circuits for aerosol delivery, 2 delivering CPAP through a high-flow generator tested at 30, 60, and 90 L/min supplementary flow and 5, 10, and 15 cm H2O CPAP and 3 with no CPAP: a T-piece configuration with one extremity closed with a cap, a T-piece configuration without cap and nebulizer positioned proximally, and a T-piece configuration without cap and nebulizer positioned distally. Albuterol was collected with a filter, and the percentage amount delivered was measured by infrared spectrophotometry. RESULTS: Configurations with continuous high-flow CPAP delivered higher percentage amounts of albuterol compared with the configurations without CPAP (9.1 ± 6.0% vs 6.2 ± 2.8%, P = .03). Among configurations without CPAP, the best performance was obtained with a T-piece with one extremity closed with a cap. In CPAP configurations, the highest delivery (13.8 ± 4.4%) was obtained with the nebulizer placed proximal to the lung simulator, independent of flow. CPAP at 15 cm H2O resulted in the highest albuterol delivery (P = .02). CONCLUSIONS: Based on our in vitro study, without CPAP, a T-piece with a cap at one extremity maximizes albuterol delivery. During high-flow CPAP, the nebulizer should always be placed proximal to the patient, after the T-piece, using the highest CPAP clinically indicated.

Respiratory System Mechanics During Low Versus High Positive End-Expiratory Pressure in Open Abdominal Surgery: A Substudy of PROVHILO Randomized Controlled Trial.

BACKGROUND: In the 2014 PROtective Ventilation using HIgh versus LOw positive end-expiratory pressure (PROVHILO) trial, intraoperative low tidal volume ventilation with high positive end-expiratory pressure (PEEP = 12 cm H2O) and lung recruitment maneuvers did not decrease postoperative pulmonary complications when compared to low PEEP (0–2 cm H2O) approach without recruitment breaths. However, effects of intraoperative PEEP on lung compliance remain poorly understood. We hypothesized that higher PEEP leads to a dominance of intratidal overdistension, whereas lower PEEP results in intratidal recruitment/derecruitment (R/D). To test our hypothesis, we used the volume-dependent elastance index %E2, a respiratory parameter that allows for noninvasive and radiation-free assessment of dominant overdistension and intratidal R/D. We compared the incidence of intratidal R/D, linear expansion, and overdistension by means of %E2 in a subset of the PROVHILO cohort. METHODS: In 36 patients from 2 participating centers of the PROVHILO trial, we calculated respiratory system elastance (E), resistance (R), and %E2, a surrogate parameter for intratidal overdistension (%E2 > 30%) and R/D (%E2 < 0%). To test the main hypothesis, we compared the incidence of intratidal overdistension (primary end point) and R/D in higher and lower PEEP groups, as measured by %E2. RESULTS: E was increased in the lower compared to higher PEEP group (18.6 [16…22] vs 13.4 [11.0…17.0] cm H2O·L−1; P < .01). %E2 was reduced in the lower PEEP group compared to higher PEEP (−15.4 [−28.0…6.5] vs 6.2 [−0.8…14.0] %; P < .05). Intratidal R/D was increased in the lower PEEP group (61% vs 22%; P = .037). The incidence of intratidal overdistension did not differ significantly between groups (6%). CONCLUSIONS: During mechanical ventilation with protective tidal volumes in patients undergoing open abdominal surgery, lung recruitment followed by PEEP of 12 cm H2O decreased the incidence of intratidal R/D and did not worsen overdistension, when compared to PEEP ⩽2 cm H2O.

Acute abdomen as a consequence of an unusual suicide attempt: intra-abdominal injection of sulfuric acid

Caustic ingestion is a common cause of life-threatening upper gastrointestinal tract injuries. It mostly happens in children as accidental exposure, but may occur in adults as a result of suicide attempt. We present a case of an acute abdomen that occurred after a peculiar way of self-administration of sulfuric acid as a suicide attempt in an adult psychiatric male patient, already known for self-harm with caustic agents in the previous years. In a few hours, the patient developed diffuse peritonitis, pneumoperitoneum, and a rapid hemodynamic deterioration, as a consequence of ileum and sigmoid necrosis, requiring an emergency surgery with the application of a damage control strategy. The patient was then transferred to intensive care unit for hemodynamic stabilization, and definitive surgical correction of the abdominal lesions was performed after 3 days with Hartmann procedure. Thirty-nine days after hospital admission, the patient was discharged. In conclusion, to our knowledge, never has been reported in the literature a case of intra-abdominal self-administration of caustic substance causing a rapid evolution of clinical conditions and requiring the application of damage control strategy.

Ventilation and gas exchange management after cardiac arrest

For several decades, physicians had integrated several interventions aiming to improve the outcomes in post-cardiac arrest patients. However, the mortality rate after cardiac arrest is still as high as 50%. Post-cardiac arrest syndrome is associated with high morbidity and mortality due to not only poor neurological outcome and cardiovascular failure but also respiratory dysfunction. To minimize ventilator-associated lung injury, protective mechanical ventilation by using low tidal volume ventilation and driving pressure may decrease pulmonary complications and improve survival. Low level of positive end-expiratory pressure (PEEP) can be initiated and titrated with careful cardiac output and respiratory mechanics monitoring. Furthermore, optimizing gas exchange by avoiding hypoxia and hyperoxia as well as maintaining normocarbia may improve neurological and survival outcome. Early multidisciplinary cardiac rehabilitation intervention is recommended. Minimally invasive monitoring techniques, that is, echocardiography, transpulmonary thermodilution method measuring extravascular lung water, as well as transcranial Doppler ultrasound, might be useful to improve appropriate management of post-cardiac arrest patients.

Complications of Regional Anesthesia

Obstetric anesthesia care is generally considered to be one of the higher risk areas of regional and general anesthetic techniques, although it is extremely safe and widely used. It is reassuring that serious complications related to central neuraxial block are uncommon, and they have to grapple with issues related to anatomic-physiologic changes in pregnancy and various other factors, including increasing trend of cesarean section, advanced maternal age, obesity, and other concomitant medical diseases. This chapter highlights the management and therapy of following regional anesthesia-related complications encountered during the obstetric regional anesthesia practice: cardiovascular, infective, hematologic, post-dural puncture headache, and neurologic complications.