The Use of ExPreS in the Weaning of Patients in Invasive Mechanical Ventilation: a Multicenter Randomized Clinical Trial

The Use of ExPreS in the Weaning of Patients in Invasive Mechanical Ventilation: a Multicenter Randomized Clinical Trial

The Use of ExPreS - Extubation Predictive Score - in the Weaning of Patients in Invasive Mechanical Ventilation: a Multicenter Randomized Clinical Trial

Pacients who use mechanical ventilation (MV) need to pass weaning, a interruption process of ventilatory support. To predict this outcome, several scores have been developed, however, fail index in weaning and extubation remains high. The objective of this study is to evaluate the effect of ExPreS - Extubation Predictive Score - on rates of successful extubation. By a randomized clinical trial, this reseach will take place in ICUs of several hospitals. Therefore, it is expected that a difference between devices to predict extubation sucess exists and, because ExPreS is a protocol that evaluates different parameters related to many organs and systems, it presents a better capacity of predicting extubation sucess in MV patients.

1. OBJECTIVES 1 General To evaluate the effect of ExPreS - Extubation Predictive Score - on rates of successful extubation. 1.2 Specific To compare sucess predctive capacity of ExPreS over standard protocol of the place of study. To identify sucess and failure rate of extubation in 48 hours according applied protocols. To compare MV time and extubation sucess rate between patients who perform spontaneous breathing trial (SBT) in T-ayre and the ones with PSV mode. PARTICIPANTS SELECTION The sample will be formed by admitted pacients in ICUs of participating institutions, on MV for more than 24 hours. The inclusion criteria are pacients admitted in ICU that are more than 18 years and in MV for more than 24 hours. The assignature of the free and informed consent form by a family member or responsable adult is necessary. The exclusion criteria are death before SBT, tracheostomy, self-extubation, accidental extubation and absence of signature of informed consent. The pacient who fails extubation and needs reintubation will not be randomized. RANDOMIZATION Pacients that meet criteria for initiation of MV weaning - improvement in the condition that caused the respiratory failure; a partial pressure of arterial oxygen higher than 60mmHg, with fraction of inspired oxygen lower than 0.4, and positive end-expiratory pressure of 5 cm of water or less; hemodynamically stable (without or low dose of vasopressors, absence of decompensated coronary insufficiency or arrhythmias with hemodynamic repercussion); patient's ability to initiate an inspiratory effort; absence of a significant acid-base imbalance, tolerate PSV mode with PEEP of 3-5 and pressure over the PEEP of 7 cmH2O with adequate ventilation (volume of 6 ml/kg and RR ˃ 35/min) - will fit the conditions and be randomized and submitted to SBT. The randomization will be executed in the program www.random.org and, for allocation concealment, generated numbers will be placed in seald and opaque envelopes with the previously defined nomenclature for each group: group I (T-ayre and standard protocol) and group II (T-ayre and ExPreS protocol). The envelopes will be numbered and placed in sequence. Therefore, evaluator and researchers are prevented from choosing the group to witch the individual will be assigned. Only one person will be responsible for opening the envelope and informing in witch group he or she was assigned to. INTERVENTION Pacients will be assigned to different interventions according to each group. The failure criteria on SBT will be the same for all groups: agitation, anxiety, decreased level of consciousness, respiratory rate higher than 35/min and/or acessory muscle use, oxygen saturation measured by pulse oxymetry lower than 90% with fraction of inspired oxygen lower than 0.4 more than 0.5, heart rate higher than 140 bpm or an increase higher than 20% of the basal, systolic blood pressure (SBP) lower than 90 mmHg or higher than 180 mmHg or presenting arrhythmia after the intiation of SBT. On gruop I (T-ayre and standard protocol), SBT must begin with the pacient in T-ayre, oxygen support that is proprotional to the fraction of inspired oxygen in invasive mechanical ventilation (IMV), during 30 minutes. If the pacient does not show any sign of SBT failure, the rapid shallow beathing index (RSBI) will be calculated and pacients with RSBI lower than 105 L/min will be extubated, meanwhile pacients with RSBI higher than 105 L/min will return to MV for at least 24 hours until the perfomance of a new SBT. On group II (T-ayre and ExPreS protocol), the pacient will be submitted to the SBT with T-ayre, with oxygen support that is proprotional to the fraction of inspired oxygen in IMV, during 30 minutes. If the pacient does not show any sign of SBT failure, ExPreS will be calculated. If punctuation is lower than or equal to 44, it indicates weaning failure and the pacient mjust return to MV for 24 hours at least. Punctuation between 45 and 58 must be evaluated if the pacient presents chronic obstructive pulmonary desease (COPD), obesity or heart desease. In this case, non invasive ventilation (NIV) should be scheduled or the weaning must be continued if there isn't any risck factors. Punctuation higher than or equal 59 indicates that the pacient can be extubated. Pacients of both groups will be submitted to evaluation of ariway permability by the cuff leak teste. Pacients with a difference higher than 10% between the inspiratory and expiratory tidal volume are able to extubation. OUTCOMES The primary outcome in both groups is extubation success in 48 hours. To be considered positive, the pacient must remain without the need of returning to MV for 48 hours at least and can't deppend on NIV on the next 48 hours after the extubation. The secondary outcomes are reintubation, IMV length of stay, ICU length of stay, hospital length of stay and in hospital mortality. RESEARCH INTRUMENTS The instruments for data collection are forms elaborated by the researchers. The form choice will be made by randomization, that will happen after 24 hours of MV with endotracheal tube, following inclusion and exclusion criteria. DATA ANALYSIS Collected data will be tabulated on Microsoft Excel program and the statistic analysis will be made on IBM SPSS statistics, v25 and GraphPad Prism 6 programs. ETHICAL ASPECTS This project was forwarded to the research comission of hospital institution of interest for authorization of research performance and to the Research Ethics Comittee of Unoesc and it was approved by number 4.524.592 (CAAE 39925920.0.0000.5367). It will follow ethical principles of the Resolution number 466/2021, of the Nacional Health Council. The research will have commitment wih data' privacy and confidentiality, by preserving the anonymity of the participants. This research is classified as low risk for research participants, causing little discomfort for the pacient, that is justified by the benefit expected. None intervention or intentional modification on physiological or psychological and socials variables of individuals that joined the study will be performed. The benefits of participating are indirect for pacients, although, by the evidence of better outcome, the study proposes better testing of protocols, witch will contribute for the elaboration of strategies to reach a better extubation sucess. The consent to join the study will be formalized by the signature of free and informed consent form, that will be given in two copies, one for the familiar member or responsible individual and one for the researchers, according to Resolution 466/2021, of the Nacional Health Council To keep all individuals' safety, precautionary measures for COVID-19 transmission will be adopted. Hands will be sanitized with alcohol 70% as enterring the institution, before and after enterring the ICU and before document manipulation. Masks will be used all the time.

Participant will not know if the ExPreS or just RSBI were calculated before extubation. The SBT will be the same for both groups. Investigator and outcomes assessor will not have access to whole patients' data, just the primary and secundary outcomes to perform the statistical analysis.

On group I (T-ayre and standard protocol), SBT must begin with the pacient in T-ayre, oxygen support that is proprotional to the fraction of inspired oxygen in invasive mechanical ventilation (IMV), during 30 minutes. If the pacient does not show any sign of SBT failure, the rapid shallow beathing index (RSBI) will be calculated and pacients with RSBI lower than 105 L/min will be extubated, meanwhile pacients with RSBI higher than 105 L/min will return to MV for at least 24 hours until the perfomance of a new SBT.

On group II (T-ayre and ExPreS protocol), the pacient will be submitted to the SBT with T-ayre, with oxygen support that is proprotional to the fraction of inspired oxygen in IMV, during 30 minutes. If the pacient does not show any sign of SBT failure, ExPreS will be calculated. If punctuation is lower than or equal to 44, it indicates weaning failure and the pacient mjust return to MV for 24 hours at least. Punctuation between 45 and 58 must be evaluated if the pacient presents chronic obstructive pulmonary desease (COPD), obesity or heart desease. In this case, non invasive ventilation (NIV) should be scheduled or the weaning must be continued if there isn't any risck factors. Punctuation higher than or equal 59 indicates that the pacient can be extubated.

Inclusion Criteria: Pacients admitted in ICU that are more than 18 years; MV for more than 24 hours; Assignature of the free and informed consent form by a family member or responsable adult. Exclusion Criteria: Death before SBT; Tracheostomy; Self-extubation; Accidental extubation; Absence of signature of informed consent.