Effect of positive expiratory pressure and type of tracheal cuff on the incidence of aspiration in mechanically ventilated patients in an intensive care unit.

OBJECTIVE: To test the effects of positive expiratory pressure on the leakage of fluid around cuffs of different tracheal tubes, in mechanically ventilated patients and in a benchtop model. DESIGN: Randomized clinical trial and experimental in vitro study. SETTING: Intensive care unit of a university hospital. PATIENTS: Forty patients recovering in the intensive care unit were ventilated in volume-controlled mode. Twenty patients were randomly intubated with Hi-Lo tubes (HL group), whereas the remaining 20 subjects were intubated with SealGuard tubes (SG group). INTERVENTIONS: Immediately after intubation and cuff inflation with 30 cm H2O, Evans blue was applied onto the cephalic surface of the tracheal tube cuff. A 5-cm H2O positive expiratory pressure was used during the first 5 hrs of stay, and thereafter it was removed. Bronchoscopy verified whether the dye leaked around the cuff. The experiment lasted 12 hrs. Leakage was also tested in vitro with the same tracheal tubes with incremental level of positive expiratory pressure. MEASUREMENTS AND MAIN RESULTS: At 1 hr, 5 hrs, and thereafter hourly until 12 hrs, bronchoscopy was used to test the presence of dye on the trachea caudal to the cuff. At the fifth hour, two patients of the HL group failed the test. One hour after positive expiratory pressure removal, all subjects in group HL exhibited a dyed lower trachea. On the other hand, one patient in group SG presented a leak at the eighth hour, and at the 12th hour three of them were still sealed. In vitro, the same level of positive expiratory pressure delayed the passage of dye around the cuff; after 30 mins positive expiratory pressure was removed, and in 10 mins all dye leaked only in the Hi-Lo tube. CONCLUSIONS: We found that 5 cm H2O positive expiratory pressure was effective in delaying the passage of fluid around the cuffs of tracheal tubes both in vivo and in vitro. The SealGuard tube proved to be more resistant to leakage than Hi-Lo.

Venovenous ECMO for Congenital Diaphragmatic Hernia: Role of Ductal Patency and Lung Recruitment.

We report a case of antenatally diagnosed left-sided congenital diaphragmatic hernia, managed on venovenous extracorporeal membrane oxygenation with an hemodynamic and ventilation strategy aimed at preventing left and right ventricular dysfunction. Keeping the ductus arteriosus open with prostaglandin infusion and optimizing lung recruitment were effective in achieving hemodynamic stabilization and an ideal systemic oxygen delivery. The patient was discharged from the hospital and had normal development at 1 year of age. The combination of ductal patency and lung recruitment has not been previously reported as a strategy to stabilize congenital diaphragmatic hernia patients undergoing venovenous extracorporeal membrane oxygenation. We believe that this approach may deserve further evaluation in prospective studies.

Anticipating events of in-hospital cardiac arrest.

STUDY OBJECTIVES: To determine whether in-hospital cardiac arrests occurring in regular wards are preceded by some event(s), and the diagnostic and therapeutic measures adopted. METHODS: From 1 May 1999 to 31 December 2001, events occurring in the 6 h preceding cardiac arrest were reviewed by checking the medical and nurse records and interviewing the attending staff. Exclusion criteria were (a) location in the Coronary Care Unit, the Intensive Care Unit, the Emergency Department and the operating rooms; (b) the presence of rapidly fatal disease; (c) the lack of adequate documentation. RESULTS: Overall, 263 cardiac arrests occurred in the period under consideration. A total of 148 patients (61 women, 87 men, aged 74.3+/-1.2 years) fulfilled the entry criteria. Anticipating events were reported in 128 patients (86.4%). These included alterations in consciousness, cardiac arrhythmias, dyspnoea and chest pain. The restoration of cardiac rhythm was obtained in 23 patients (15.5%). Eight (5.4%) survived without major neurological sequelae. Survivors were significantly younger than non-survivors (survivors 44.3+/-6.8 years; non-survivors 76.7+/-2.1 years; P<0.005). In a substantial number of cases, ranging from 23 to 81%, according to the anticipating event, no diagnostic investigations were performed. CONCLUSION: Most in-hospital cardiac arrests are preceded by events that often go overlooked and whose correct interpretation could be associated with a reduced mortality rate.

Beneficial effect of fenoldopam mesylate in preventing peak blood lactate level during cardiopulmonary bypass for paediatric cardiac surgery.

OBJECTIVES: To evaluate the efficacy of fenoldopam mesylate (dose 0.2 µg/kg/min) in reducing the occurrence of hyperlactataemia (i.e. peak level of blood lactate >2.0 mM/l) during cardiopulmonary bypass (CPB) in paediatric cardiac surgery. Hyperlactataemia occurring during CPB for paediatric cardiac surgery is considered an early biomarker of an increased risk of poor outcome. METHODS: This was a dose/effectiveness clinical study applying Simon's two-stage optimal design with 5% type I error rate and 90% statistical power. Following parents' written informed consent, 53 children undergoing elective cardiac surgery with CPB between March 2009 and February 2012 were enrolled. Inclusion criteria were children weighing 3-15 kg scheduled for elective cardiac surgery and with expected CPB time of 60-180 min. Patients requiring surgery with total circulatory arrest were excluded. All patients received fenoldopam infusion at a dose of 0.2 µg/kg/min from the beginning of surgery until the end of CPB. RESULTS: The primary end-point was the evaluation of response to fenoldopam, i.e., blood lactate levels ≤2.0 mM/l. A total of 53 children, median age 5.7 months (range 11 days to 48 months) were enrolled. In the first stage, 18 of 19 (95%) children achieved normalization of lactate values. Then the study was continued to stage II by enrolling an additional 34 patients. At study conclusion, 96.2% of patients showed normalized lactate values. Fenoldopam infusion was well tolerated in all patients. No adverse events were observed. CONCLUSIONS: In this study, fenoldopam at a dose of 0.2 µg/kg/min was well tolerated in paediatric patients undergoing elective cardiac surgery with CPB. In 96.2% of patients, infusion of fenoldopam was associated with intraoperative blood lactate <2.0 mM/l.