Hemodynamic Variable, Laparoscopic Bariatric Surgery, Positive End-expiratory Pressure, Postoperative Atelectasis
Conditions
Brief summary
The aim of this study is to evaluate the effectiveness of intraoperative individualized positive end-expiratory pressure (PEEPIND) titration, compared to fixed positive end-expiratory pressure of 5 cmH2O, on oxygenation, hemodynamic variables, and early postoperative complications in obese patients undergoing laparoscopic bariatric surgery.
Detailed description
Obesity is a major health problem, and the incidence is increasing worldwide. So far, the only treatment for morbid obesity with good long-term results is bariatric surgery. Obese patients have unique respiratory physiology and ventilatory mechanics characteristics. Their lung function is impaired due to the reduction of oxygen reserve, functional residual capacity, and lung compliance. In addition, they frequently present with respiratory comorbidities, which increases the risk of developing postoperative pulmonary complications (PPCs) such as atelectasis especially after procedures under general anesthesia. Atelectasis has been hypothesized as a main cause of postoperative hypoxemia. To reduce the incidence of atelectasis, positive end-expiratory pressure (PEEP) and recruitment maneuvers are used as a protective lung strategy to improve gas exchange and lung mechanics through reopening collapsed alveoli and maintaining the aeration of lungs. Application of PEEP may also eliminate auto-PEEP without increasing plateau pressure.
Interventions
OTHERPositive end-expiratory pressure 5 (PEEP 5)
Fixed positive end-expiratory pressure of 5 cmH2O will be maintained throughout the duration of surgery
OTHERIndividualized positive end-expiratory pressure (PEEPIND)
Patients will receive the individualized positive end-expiratory pressure. Titration process will be started after establishment of pneumoperitoneum: setting the initial PEEP to 5 cmH2O, then increasing positive end-expiratory pressure (PEEP)according to the gradient of 2 cmH2O every 3 min, calculating static compliance (Cstat) according to the formula: \[Cstat = VT/Pplat - PEEP\] (Pplat = plateau pressure), then gradually increasing positive end-expiratory pressure , until the calculated Cstat shows a downward trend, set its previous PEEP (corresponding to PEEP for high Cstat) as the optimal PEEPIND for this patient. The highest PEEP is limited to 20 cmH2O
Sponsors
Tanta University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* Age from 21 to 60 years. * Both sexes. * American Society of Anesthesiologists (ASA) physical status class I-III * Patients who are scheduled for elective laparoscopic bariatric surgery under general anesthesia.
Exclusion criteria
* Patients who are unwilling to participate in the study * Actively smokers. * Patients who had a history of Chronic obstructive pulmonary disease or bronchial asthma. * Patients who are receiving renal replacement therapy prior to surgery. * Patients who had a history of heart failure. * Pregnant. * Patients who have allergies to any drug used in the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intraoperative oxygenation | One hour after extubation | Intraoperative oxygenation which will be assessed by P/F ratio (the ratio of arterial oxygen partial pressure (PaO2 in mmHg) to fractional inspired oxygen (FiO2 expressed as a fraction, not a percentage). PaO2/FiO2: will be measured at before induction of anesthesia, immediately after intubation, after PEEP titration, one hour after pneumoperitoneum, before extubation, one hour after extubation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate(HR) | One hour after extubation | Heart rate will be measured before induction of anesthesia, immediately after intubation, after positive End-Expiratory Pressure titration, one hour after pneumoperitoneum, before extubation, and one hour after extubation. |
| Volume of total fluid infusion | Till the end of surgery | The total volume of the administered fluids will be recorded. |
| Dosage of vasopressors | Till the end of surgery | The total volume of the administered vasopressors will be recorded. |
| Mean arterial pressure(MAP) | One hour after extubation | Mean arterial pressure will be measured before induction of anesthesia, immediately after intubation, after positive End-Expiratory Pressure titration, one hour after pneumoperitoneum, before extubation, and one hour after extubation. |
| Early postoperative pulmonary complication | First 24 hours postoperatively | Any early postoperative pulmonary complication in the first postoperative 24 hours will be recorded. |
| Length of hospital stay | 28 days postoperatively | Time from admission till hospital discharge |
| Lung ultrasound scores | 12 hours postoperatively | Lung ultrasound scans will be performed 3 times for each patient, before induction of anesthesia, one hour after extubation and 12 hours postoperatively. Patients will be scanned in the supine position as follows: Each hemithorax will be divided into 6 regions using 3 longitudinal lines (parasternal, anterior, and posterior axillary) and 2 axial lines (one above the diaphragm and the other 1 cm above the nipples). The 12-lung regions will be scanned sequentially from right to left, cranial to caudal and anterior to posterior. Each region will be assessed using a 2-dimensional view with the probe placed parallel to the ribs. The degree of B-lines will be divided into 4 grades according to lung ultrasound score for consolidation and aeration and scored between 0 and 3: (0) fewer than 3 isolated B-lines. 1. multiple well-defined B-lines. 2. multiple coalescent B-lines. 3. white lung. |
Countries
Egypt
Contacts
Primary ContactHeba Z Khattab, Master
Outcome results
None listed