Evaluation of the spontaneous breathing trial in burn intensive care patients

Weaning-associated interventions for ventilated intensive care patients: A scoping review

BACKGROUND

Mechanical ventilation is a core intervention in critical care, but may also lead to negative consequences. Therefore, ventilator weaning is crucial for patient recovery. Numerous weaning interventions have been investigated, but an overview of interventions to evaluate different foci on weaning research is still missing.

AIM

To provide an overview of interventions associated with ventilator weaning.

STUDY DESIGN

We conducted a scoping review. A systematic search of the Medline, CINAHL and Cochrane Library databases was carried out in May 2023. Interventions from studies or reviews that aimed to extubate or decannulate mechanically ventilated patients in intensive care units were included. Studies concerning children, outpatients or non-invasive ventilation were excluded. Screening and data extraction were conducted independently by three reviewers. Identified interventions were thematically analysed and clustered.

RESULTS

Of the 7175 records identified, 193 studies were included. A total of six clusters were formed: entitled enteral nutrition (three studies), tracheostomy (17 studies), physical treatment (13 studies), ventilation modes and settings (47 studies), intervention bundles (42 studies), and pharmacological interventions including analgesic agents (8 studies), sedative agents (53 studies) and other agents (15 studies).

CONCLUSIONS

Ventilator weaning is widely researched with a special focus on ventilation modes and pharmacological agents. Some aspects remain poorly researched or unaddressed (e.g. nutrition, delirium treatment, sleep promotion).

RELEVANCE TO CLINICAL PRACTICE

This review compiles studies on ventilator weaning interventions in thematic clusters, highlighting the need for multidisciplinary care and consideration of various interventions. Future research should combine different interventions and investigate their interconnection.

Critical Care of the Burn Patient

Care of the critically ill burned patient must integrate a multidisciplinary care team composed of burn care specialists. As resuscitative mortality decreases more patients are surviving to experience multisystem organ failure relating to complications of their injuries. Clinicians must be aware of physiologic changes following burn injury and the implicated impacts on management strategy. Promoting wound closure and rehabilitation should be the backdrop for which management decisions are made.

Care of the Critically Injured Burn Patient

Care of the critically injured burn patient presents unique challenges to the intensivist. Certified burn centers are rare and geographically sparse, necessitating that much of the initial management of patients with severe burn injuries must happen in the pre-burn center setting.1 Severe burn injuries often lead to a wide range of complications that extend beyond the loss of skin integrity and require specialized care. As such, medical intensivists are often called upon to stabilize these critically injured patients. This focused review outlines the clinical care of these medically complex patients, including airway management, post-burn complications, volume resuscitation, nutrition, and end-of-life care.

Extubation Failure in a Burn Intensive Care Unit: Examination of Contributing Factors

Extubation failure is associated with negative outcomes making the identification of risk factors for failure paramount. Burn patients experience a high incidence of respiratory failure requiring mechanical ventilation. There is no consensus on the acceptable rate of extubation failure and many conventional indices do not accurately predict extubation outcomes in burn patients. The purpose of this study was to examine the rate of extubation failure in the burned population and to examine the impact of factors on extubation outcomes. Burn patients from a single center over 9 years were examined and included if they were intubated prior to arrival or within 48 hours of admission and underwent a planned extubation. From this cohort, a matched case-control analysis based on age, TBSA, and sex was performed of patients who succeeded after extubation, defined as not requiring reintubation within 72 hours, to those who failed. Characteristics and clinical parameters were compared to determine whether any factors could predict extubation failure. There was a 12.3% incidence of extubation failure. In the matched case-control analysis, the presence of inhalation injury was associated with extubation success. Higher heart rate and lower serum pH were associated with extubation failure. ANCOVA analysis demonstrated that a sodium trending higher before extubation was associated with more successes, possibly indicative of a lower volume status. Classic extubation criteria do not accurately predict extubation outcomes in burn patients; analysis of other parameters may be able to provide better predictions. A constellation of these parameters needs to be studied prospectively.

Achieving Quality Health Outcomes Through the Implementation of a Spontaneous Awakening and Spontaneous Breathing Trial Protocol

Background:

Continuous sedation infusions can lead to prolonged treatment with mechanical ventilation (MV), resulting in serious complications. Spontaneous awakening trials (SATs) and spontaneous breathing trials (SBTs) are strategies that limit the amount of sedative agents a patient receives and promote extubation.

Objective:

The objective of this performance improvement project was to evaluate the outcomes of an evidence-based practice protocol that included SATs and SBTs on the duration of treatment with MV, ventilator utilization ratio (VUR), intensive care unit (ICU) length of stay (LOS), and incidence of self-extubations and reintubations.

Methods:

A convenience sample of 112 discharged patients’ medical records was used for this descriptive, comparative secondary data analysis. An evidence-based SAT/SBT practice protocol was designed by a multidisciplinary team and implemented. Three months after the implementation, a retrospective medical record review was conducted to evaluate patient outcomes.

Results:

The median duration of treatment with MV was significantly lower in the postprotocol group (3.8 days vs 2.7 days, U = 1222, Z = −2.013, P = .04, r = 0.19). A significant decrease was found in the VUR (0.68 vs 0.52, U = 2.5, Z = −2.293, P = .02, r = 0.69). No difference was found in the ICU LOS and frequency of self-extubation or reintubation after a self-extubation between the preprotocol and postprotocol groups. Ten of 45 SAT opportunities (22%) and 67 of 130 SBT opportunities (52%) were missed by the nurse or the respiratory therapist.

Conclusion:

The duration of treatment with MV and the VUR were reduced in patients who received the SAT/SBT protocol. The incidence of self-extubation was not different when an SAT was implemented. The ICU LOS was not reduced in patients who received SATs and SBTs.

Cough strength, secretions and extubation outcome in burn patients who have passed a spontaneous breathing trial

The aim of this study was to develop a clinical prediction model to inform decisions about the timing of extubation in burn patients who have passed a spontaneous breathing trial (SBT). Rapid shallow breathing index, voluntary cough peak flow (CPF) and endotracheal secretions were measured after each patient had passed a SBT and just prior to extubation. We used multiple logistic regression analysis to identify variables that predict extubation outcome. Seventeen patients failed their first trials of extubation (14%). CPF and endotracheal secretions are strongly associated with extubation outcome (p<0.0001). Patients with CPF ≤60 L/min are 9 times as likely to fail extubation as those with CPF >60 L/min (risk ratio=9.1). Patients with abundant endotracheal secretions are 8 times as likely to fail extubation compared to those with no, mild and moderate endotracheal secretions (risk ratio=8). Our clinical prediction model combining CPF and endotracheal secretions has strong predictive capacity for extubation outcome (area under receiver operating characteristic curve=0.96, 95% confidence interval 0.91-0.99) and therefore may be useful to predict which patients will succeed or fail extubation after passing a SBT.