Effects of PEEP on Parameters of Tissue Perfusion in Patients Post Cardiac Surgery

NCT ID: NCT03753022

Last Updated: 2018-11-29

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 125 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-01-31
• Study Completion Date: 2019-12-31

Brief Summary

Pulmonary dysfunction is a condition inherent in cardiac surgery because of various interventions, such as general anesthesia, a median sternotomy, cardiopulmonary bypass and establishment of internal thoracic artery dissection.

In situations when there is a deterioration in oxygenation, increased positive pressure on the airways end pressure (PEEP) can be used as therapeutic mode by reversing severe hypoxemia resulting pulmonary shunt. But the use of PEEP has been associated to reduced cardiac output, due mainly to decrease systemic venous return consequent to increased intrathoracic pressure, and thus might reduce tissue oxygenation. Moreover, the increased transpulmonary gradient may also impair right ventricular ejection exacerbating the hemodynamic consequences in some patients, which in clinical practice this diagnosis may be difficult to perform.

In hypovolemic patients or those with cardiac changes may become even more pronounced, resulting in accentuation of low flow and systemic hypotension entailing changes in markers of tissue perfusion commonly measured by venous saturation central difference venoarterial carbon dioxide and lactate. The hypothesis of the investigators is that PEEP of 10 cmH2O and 15 cmH2O can be applied to reverse lung damage in patients in the immediate postoperative myocardial revascularization without repercussion tissue importantly in markers of tissue perfusion.

The objective is to evaluate the effects of different optimization levels of PEEP on gas exchange and influences the tissue perfusion after coronary artery bypass graft surgery.

Detailed Description

This is a prospective, randomized study and will be performed on patients who accept coronary artery bypass grafting with cardiopulmonary bypass, the conscious openness to participate in the study. Age, sex, body mass index (BMI), smoking habits, diagnosis, additional diseases, drugs used, surgery, intervention, peroperative supportive treatments, left ventricular ejection fraction, post operative blood and cardiopulmonary bypass (CPB) time (min), cross clamp time (min), duration of operation, postoperative extubation period, intensive care day of hospitalization, day of hospitalization will be recorded.The study was planned in 3 groups. Group G5 (control group: no changes will be made to the value of PEEP). Group G10 [after 30 minutes of admission (time 0) the PEEP will be raised to 10 cmH2O (time1) for 30 minutes and then returned to 5 cmH2O (time 2)]. Group G15 [after 30 minutes of admission (time 0) the PEEP will be raised to 15 cmH2O (time 1) for 30 minutes and then returned to 5 cm H2O (time 2)]. At each time of protocol (0, 1 and 2) will be collected: arterial blood gas measurements (partial pressure of arterial oxygen [PaO2] and partial pressure of carbon dioxide ([PaCO2]), the ratio between the partial oxygen pressure, inspired oxygen fraction (PaO2/FiO2) and pH. Also, will be performed parameters of tissue perfusion: central venous oxygen saturation ([SVO2]), arterial blood lactate, venoarterial CO2 difference ([Dif VA CO2]) and vital signs. In all other respects, treatment will follow the standard of care.

Conditions

Coronary Artery Disease; Coronary Artery Bypass Grafting; Acute Lung Injury

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: SEQUENTIAL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

Group G5

Patients submitted to CABG and peep 5

Group Type: SHAM_COMPARATOR

Group G5

Intervention Type: OTHER

Submitted to peep 5

Group G10

Patients submitted to CABG and peep 10

Group Type: EXPERIMENTAL

Group G10

Intervention Type: OTHER

Submitted to peep 10

Group G15

Patients submitted to CABG and peep 15

Group Type: EXPERIMENTAL

Group G15

Intervention Type: OTHER

Submitted to peep 15

Interventions

Group G5

Submitted to peep 5

Intervention Type: OTHER

Group G10

Submitted to peep 10

Intervention Type: OTHER

Group G15

Submitted to peep 15

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• elective and isolated CABG, ejection fraction greater than 40%

Exclusion Criteria

• patients with a diagnosis of pulmonary disease, emergency surgery and mechanical ventilation prior to surgery.

Postoperative patients who had radiological abnormalities suggestive of pneumothorax, atrial or ventricular arrhythmias, electrical ischemic changes on ECG, pulse pressure variation of more than 13, hemodynamic instability characterized by mean arterial pressure less than 60 mmHg, nor epinephrine greater than 0.5 mcg/Kg/ min and the presence of increased bleeding through the drains (greater than 2 ml \ kg \ h) the protocol was discontinued and the patient excluded from the study.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Vanessa Marques Ferreira

UNKNOWN

Sponsor Role: collaborator

Federal University of São Paulo

OTHER

Sponsor Role: lead

Responsible Party

Solange Guizilini

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Other Identifiers

89704818.6.0000.5505

Identifier Type: -

Identifier Source: org_study_id