Effects of Different Ventilation Patterns on Lung Injury

Not Applicable

• Conditions: Lung Injury
• Interventions: Procedure: volume controlled ventilation; Procedure: pressure-controlled ventilation-volume guaranteed

• Registration Number: NCT03960853
• Lead Sponsor: Sixth Affiliated Hospital, Sun Yat-sen University

Brief Summary

In 1967, the term "respirator lung" was coined to describe the diffuse alveolar infiltrates and hyaline membranes that were found on postmortem examination of patients who had undergone mechanical ventilation.This mechanical ventilation can aggravate damaged lungs and damage normal lungs. In recent years, Various ventilation strategies have been used to minimize lung injury, including low tide volume, higher PEEPs, recruitment maneuvers and high-frequency oscillatory ventilation. which have been proved to reduce the occurrence of lung injury.

In 2012,Needham et al. proposed a kind of lung protective mechanical ventilation, and their study showed that limited volume and pressure ventilation could significantly improve the 2-year survival rate of patients with acute lung injury.Volume controlled ventilation is the most commonly used method in clinical surgery at present.Volume controlled ventilation(VCV) is a time-cycled, volume targeted ventilation mode, ensures adequate gas exchange. Nevertheless, during VCV, airway pressure is not controlled.Pressure controlled ventilation（PCV） can ensure airway pressure,however minute ventilation is not guaranteed.Pressure controlled ventilation-volume guarantee(PCV-VG) is an innovative mode of ventilation utilizes a decelerating flow and constant pressure. Ventilator parameters are automatically changed with each patient breath to offer the target VT without increasing airway pressures. So PCV-VG has the advantages of both VCV and PCV to preserve the target minute ventilation whilst producing a low incidence of barotrauma pressure-targeted ventilation.

Current studies on PCV-VG mainly focus on thoracic surgery, bariatric surgery and urological surgery, and the research indicators mainly focus on changes in airway pressure and intraoperative oxygenation index.The age of patients undergoing laparoscopic colorectal cancer resection is generally higher, the cardiopulmonary reserve function is decreased, and the influence of intraoperative pneumoperitoneum pressure and low head position increases the incidence of intraoperative and postoperative pulmonary complications.Whether PCV-VG can reduce the incidence of intraoperative lung injury and postoperative pulmonary complications in elderly patients undergoing laparoscopic colorectal cancer resection, and thereby improve postoperative recovery of these patients is still unclear.

Detailed Description

One hundred patients undergoing elective laparoscopic colorectal cancer resection (age \> 65 years old, body mass index(BMI）18-30 kg/m2, American society of anesthesiologists(ASA )grading Ⅰ - Ⅲ ) will be randomly assigned to volume control ventilation(VCV)group and pressure controlled ventilation-volume guarantee(PCV-VG)group.General anesthesia combined with epidural anesthesia will be used to both groups.

Ventilation settings in both groups are VT 8 mL/kg,inspiratory/expiratory (I/E) ratio 1:2,inspired oxygen concentration (FIO2) 0.5 with air,2.0 L/min of inspiratory fresh gas flow,positive end-expiratory pressure (PEEP) 0 millimeter of mercury （mmHg）,respiratory rate (RR) was adjusted to maintain an end tidal CO2 pressure (ETCO2) of 35 -45 mmHg.

In operation dates will be collected at the following time points: preanesthesia, 1 hour after pneumoperitoneum,2 hours after pneumoperitoneum ,30 minutes after admission to post-anaesthesia care unit (PACU) .The dates collected or calculated are the following:1)peak airway pressure,plate airway pressure, mean inspiratory pressure, dynamic compliance, RR,Exhaled VT andETCO2，2) Arterial blood gas analysis: arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2),power of hydrogen（PH）, and oxygen saturation (SaO2)，3) Oxygenation index (OI) calculation; PaO2/FIO2, 4) Ratio of physiologic dead-space over tidal volume(Vd/VT) (expressed in %) was calculated with Bohr's formula ; Vd/VT = (PaCO2 - ETCO2)/PaCO2,5) Hemodynamics: heart rate, mean arterial pressure (MAP),and central venous pressure （CVP），6) lung injury markers ：Interleukin 6(IL6）,Interleukin 8（IL8）,Clara cell protein 16（CC16）,Solution advanced glycation end products receptor（SRAGE）,tumor necrosis factor α(TNFα) .

Investigators will collect the following dates according to following-up after surgery: the incidence of postoperation pulmonary complications(PPC) based on PPC scale within seven days , incidence of pneumonia within seven days after surgery,incidence of atelectasis within seven days after surgery,length of hospital days after surgery, the incidence of postoperative unplanned admission to ICU, the incidence of operation complications within 7 days after surgery, the incidence of postoperative systematic complications within 7 days after surgery.

Study Timeline

• Study First Submitted: 2019-05-19
• Study First Submitted QC: 2019-05-21
• Study First Posted: 2019-05-23
• Status Verified: 2019-06
• Study Start: 2019-08-01
• Last Update Submitted: 2020-01-05
• Last Update Posted: 2020-01-07
• Primary Completion: 2021-12-31
• Study Completion: 2021-12-31

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

1. scheduled for Laparoscopic colorectal cancer resection
2. age >65 years
3. body mass index(BMI) 18-30kg / m2
4. ASA gradingⅠ-Ⅲ

Exclusion Criteria

1. history of lung surgery
2. severe restrictive or obstructive pulmonary disease (preoperative lung function test: forced vital capacity(FVC)< 50% predictive value of FVC,forced expiratory volume at one second(FEV1)< 50% predictive value of FEV1
3. Acute respiratory failure, pulmonary infection, ALI/ARDS, and acute stage of asthmaAcute respiratory failure, pulmonary infection, acute lung injury(ALI),acute respiratory distress syndrome(ARDS), and acute stage of asthma (bronchodilators were needed for treatment) were found within 1 month before surgery
4. Patients at risk of preoperative reflux aspiration
5. Preoperative positive pressure ventilation (as obstructive sleep apnea hypopnea syndrome patients) or long-term home oxygen therapy were performed
6. Serious heart, liver and kidney diseases: heart function class more than 3, severe arrhythmia (sinus bradycardia (ventricular rate < 60 times/min), atrial fibrillation, atrial flutter, atrioventricular block, frequent premature ventricular and polyphyly ventricular early, early to R on T, ventricular fibrillation and ventricular flutter), acute coronary syndrome, liver failure, kidney failure
7. Neuromuscular diseases affect respiratory function, such as Parkinson's disease, myasthenia gravis and cerebral infarction affect normal breathing
8. Mental illness, speech impairment, hearing impairment
9. Contraindications for spinal anesthesia puncture
10. Refuse to participate in this study or participate in other studies -

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
volume controlled ventilation	volume controlled ventilation	patients will be allocated to volume controlled ventilation in operation
pressure-controlled ventilation-volume guaranteed	pressure-controlled ventilation-volume guaranteed	patients will be allocated to pressure-controlled ventilation volume guaranteed in operation

Primary Outcome Measures

Name	Time	Method
occurrence rate of Oxygenation index≤300mmHg	10minutes before anesthesia,1 hour after pneumoperitoneum,2 hour after pneumoperitoneum,30 minutes after after extubation	Oxygenation index(OI)=PaO2/FiO2

Secondary Outcome Measures

Name	Time	Method
Plateau airway pressure	through mechanical ventilation,average of 3 hours	Plateau airway pressure（Pplat, cm H2O）
assessing change of Alveolar-arterial oxygen tension difference	10 minutes before anesthesia, 1 hour after pneumoperitoneum, 2 hours after pneumoperitoneum, 30 minutes after extubation	Alveolar-arterial oxygen tension difference (mmHg）
incidence of pneumonia	Day 0 to 7 after surgery	record the occurrence rate of pneumonia after surgery
peak airway pressure	through mechanical ventilation,average of 3 hours	Peak airway Pressure（Ppeak, cm H2O)
assessing change of Respiratory index	10 minutes before anesthesia, 1 hour after pneumoperitoneum, 2 hours after pneumoperitoneum, 30 minutes after extubation	Fraction of inspired oxygen (FiO2); Respiratory index (RI) =Ratio of alveolar-arterial oxygen tension difference to FiO2
assessing change of Alveolar dead space fraction	10 minutes before anesthesia, 1 hour after pneumoperitoneum, 2 hours after pneumoperitoneum,30 minutes after extubation	Arterial carbon dioxide partial pressure (PaCO2); partial pressure of carbon dioxide in endexpiratory gas (PetCO2); Alveolar dead space fraction (Vd/Vt）=(PaCO2-PetCO2)/ PaCO2;
assessing change of Tumor Necrosis Factor alpha	10 minutes before anesthesia,30 minutes after extubation	Tumor Necrosis Factor alpha (TNF-α, pg/ml)
Occurrence rate of operation complications	within 7 days after operation	abdominal abscess, anastomotic fistula, bleeding and the incidence of reoperation within 7 days
incidence of pulmonary atelectasis	Day 0 to 7 after surgery	record the occurrence rate of pulmonary atelectasis after surgery
Dynamic lung compliance	through mechanical ventilation,average of 3 hours	Dynamic lung compliance (Cdyn , ml/cm H2O)= Vt/ (Ppeak-PEEP)
assessing change of Interleukin 6	10 minutes before anesthesia,30 minutes after extubation	Interleukin 6 (IL-6, pg/ml)
Antibiotic dosages	within 7 days after surgery	record the Antibiotic dosages within 7 days after surgery
Length of ICU stay within 30 days after surgery	within 30 days after surgery	Length of ICU stay within 30 days after surgery
Occurrence rate of pulmonary complications	Day 0 to 7 after surgery	Pulmonary complications were assessed using the Postoperation Pulmonary complication ( PPC) scale,The scale is divided into four grades, with 0 indicating no pulmonary complications and 1 to 4 indicating increasingly severe pulmonary complications.
Arterial partial pressure of oxygen	10 minutes before anesthesia, 1 hour after pneumoperitoneum, 2 hours after pneumoperitoneum, 30 minutes after extubation	Arterial partial pressure of oxygen (PaO2, mmHg）
assessing change of Advanced glycation end products receptor	10 minutes before anesthesia,30 minutes after extubation	Advanced glycation end products receptor (RAGE, pg/ml)
assessing change of Interleukin 8	10 minutes before anesthesia,30 minutes after extubation	Interleukin 8 (IL-8, pg/ml)
Occurrence rate of Systemic complications	within 7 days after surgery	Systemic complications including sepsis and septic shock
Death from any cause	within 30 days after surgery	Death from any cause 30 days after surgery
Static lung compliance	through mechanical ventilation,average of 3 hours	Static lung compliance (Csta, ml/cm H2O) = Vt/ (Pplat-PEEP)
The occurrence rate of hypoxemia after surgery	within 7 days after surgery	The occurrence rate of hypoxemia (SPO2\<90% or PaO2\<60 mmHg) after surgery
assessing change of lactic acid	10 minutes before anesthesia, 1 hour after pneumoperitoneum, 2 hours after pneumoperitoneum, 30 minutes after extubation	lactate ( LAC), mmol/L
assessing change of Clara cell protein 16,	10 minutes before anesthesia,30 minutes after extubation	Clara cell protein 16,
The occurrence rate of hypoxemia in PACU	30 minutes after extubation	The occurrence rate of hypoxemia (SPO2\<90% or PaO2\<60 mmHg) in PACU
incidence of Unplanned admission to ICU	within 30 days after surgery	Unplanned admission to ICU within 30 days after surgery
Length of hospital stay within 30 days after surgery	within 30 days after surgery	Length of hospital stay within 30 days after surgery

Trial Locations

Locations (1)

Six Affiliated Hospital, Sun Yat-sen University; 🇨🇳 Guangzhou, Guangdong, China