Biomedical subjects

Ard Struijs

Publications and source records attributed to Ard Struijs.

4 recordsLinked to original sources

PubMed2006

Open lung ventilation does not increase right ventricular outflow impedance: An echo-Doppler study.

OBJECTIVE: Ventilation according to the open lung concept (OLC) consists of recruitment maneuvers, followed by low tidal volume and elevated positive end-expiratory pressure (PEEP). Elevated PEEP is associated with an increased right ventricular afterload. We investigated the effect of OLC ventilation on right ventricular outflow impedance during inspiration and expiration in patients after cardiac surgery using transesophageal echo-Doppler. DESIGN: A prospective, single-center, crossover, randomized, controlled clinical study. SETTING: Cardiothoracic intensive care unit of a university hospital. PATIENTS: Twenty-eight patients scheduled for elective cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: In the intensive care unit, each patient was ventilated for approximately 30 mins according to both OLC and conventional ventilation. During OLC ventilation, recruitment maneuvers were applied until PaO2/FiO2 was >375 torr (50 kPa); during conventional ventilation no recruitment maneuvers were performed. MEASUREMENTS AND MAIN RESULTS: Transesophageal echo-Doppler measurements were performed at end-inspiration and end-expiration in a steady-state condition, 20 mins after initiation of a ventilation strategy. Mean acceleration of flow was determined in the long axis of the pulmonary artery in a transverse axis view. During OLC ventilation, a total PEEP of 14 +/- 4 cm H2O was applied vs. 5 cm H2O during conventional ventilation. Mean acceleration during expiration was comparable between groups. During inspiration, OLC ventilation did not cause a decrease of mean acceleration compared with expiration, whereas this did occur during conventional ventilation. CONCLUSIONS: Despite the use of elevated PEEP levels, ventilation according to OLC does not change right ventricular outflow impedance during expiration and decreases right ventricular outflow impedance during inspiration.

Blood Flow Velocity↗

PubMed2005

Ventilation according to the open lung concept attenuates pulmonary inflammatory response in cardiac surgery.

OBJECTIVE: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response, which is correlated with outcome. We hypothesized that ventilation according to the open lung concept (OLC) attenuates cytokine release. METHODS: A prospective, single center randomized controlled clinical study containing 62 patients scheduled for elective coronary artery bypass graft and/or valve surgery with cardiopulmonary bypass. Before surgery, patients were randomly assigned to three groups: (1) conventional mechanical ventilation (CV), (2) OLC started after arrival on the ICU (late open lung, LOL), and (3) OLC started directly after intubation (early open lung, EOL). In both OLC groups, recruitment maneuvers were applied until PaO(2)/FiO(2)>50. The CV group received no recruitment maneuvers. Interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma were measured preoperatively, immediately after cessation of CPB, and 3h, 5h, 24h, 2, and 3 days after cessation of CPB. RESULTS: CPB caused a significant increase of IL-6, IL-8, and IL-10 in all groups. Thereafter, IL-8 decreased significantly more rapidly in both OLC groups compared to CV. IL-10 decreased significantly more rapidly after CPB only in the EOL group, compared with CV. Three hours after cessation of the CPB, IL-10 was already comparable with preoperative levels in the EOL group, but not in the LOL or CV group. IL-6, TNF-alpha, and IFN-gamma did not differ significantly between groups. CONCLUSIONS: OLC ventilation leads to an attenuated inflammatory response, presumably by reducing additional lung injury after cardiac surgery. Studies on cytokines after cardiac surgery should take these findings into account.

Aged↗

PubMed2005

Open lung ventilation improves functional residual capacity after extubation in cardiac surgery.

OBJECTIVE: After cardiac surgery, functional residual capacity (FRC) after extubation is reduced significantly. We hypothesized that ventilation according to the open lung concept (OLC) attenuates FRC reduction after extubation. DESIGN: A prospective, single-center, randomized, controlled clinical study. SETTING: Cardiothoracic operating room and intensive care unit of a university hospital. PATIENTS: Sixty-nine patients scheduled for elective coronary artery bypass graft and/or valve surgery with cardiopulmonary bypass. INTERVENTIONS: Before surgery, patients were randomly assigned to three groups: (1) conventional ventilation (CV); (2) OLC, started after arrival in the intensive care unit (late open lung); and (3) OLC, started directly after intubation (early open lung). In both OLC groups, recruitment maneuvers were applied until Pao2/Fio2 was >375 Torr (50 kPa). No recruitment maneuvers were applied in the CV group. MEASUREMENTS AND MAIN RESULTS: FRC was measured preoperatively and 1, 3, and 5 days after extubation. Peripheral hemoglobin saturation (Spo2) was measured daily till the third day after extubation while the patient was breathing room air. Hypoxemia was defined by an Spo2 value < or =90%. Averaged over the 5 postoperative days, FRC was significantly higher in the early open lung group and tended to be higher in the late open lung group, in comparison with the CV group (mean +/- sem: CV, 1.8 +/- 0.1; late open lung,1.9 +/- 0.1; and early open lung, 2.2 +/- 0.1l). In the CV group, 37% of the patients were hypoxic on the third day after extubation, compared with none of the patients in both OLC groups. CONCLUSIONS: After cardiac surgery, earlier application of OLC resulted in a significantly higher FRC and fewer episodes of hypoxemia than with CV after extubation.

Adult↗

PubMed2004

Single-stage surgical repair of benign laryngotracheal stenosis in adults.

BACKGROUND: Benign laryngotracheal stenosis causes considerable morbidity. In a retrospective study, we describe the results of our surgical treatment. METHODS: Between June 1999 and June 2002, 14 adults with laryngotracheal stenosis were referred to our hospital. Stenosis resulted from mechanical ventilation in 11 patients, from Wegener's granulomatosis in 2 patients, and from strangulation in 1 patient. Eleven patients had a tracheotomy. One patient was found unfit for surgery. Nine patients underwent cricotracheal resection (CTR) with end-to-end anastomosis, and four patients underwent single-stage laryngotracheoplasty (SS-LTP) without stenting. RESULTS: There were no perioperative deaths. Patients were extubated after mean of 3 days (range, 0-10 days; CTR 2.3 days vs SS-LTP 3.5 days, p=.45). There were in-hospital complications in five patients. Mean hospital stay was 19 days (range, 8-53 days; after CTR 24 days vs SS-LTP 9 days, p=.015). With regard to airway patency and voice recovery, 10 patients (77%) had good results, including 1 patient with two readmissions, and 3 (23%) had satisfactory results, including 1 patient with 11 additional nonsurgical interventions. CONCLUSIONS: Benign laryngotracheal stenosis in the adult patient can be repaired successfully using a strategy of two single-stage surgical procedures. All patients had good or satisfactory functional results. A multidisciplinary approach was essential to achieve these good results.

Adult↗