Attention-seeking actions by patients on mechanical ventilation in intensive care units: A phenomenological-hermeneutical study.

AIMS AND OBJECTIVES: The aim of this study was to explore the interaction between mechanically ventilated patients and healthcare personnel in intensive care units (ICUs), with a special emphasis on patients' initiative to communicate. BACKGROUND: Patients on mechanical ventilation in ICUs tend to be less sedated today compared to standard care in the past. Their experiences of being voiceless may cause emotional distress, and for many patients, communication is difficult. Healthcare personnel are reported to be the main initiators of the communication exchanges that occur. DESIGN: An observational study with a phenomenological-hermeneutical approach. METHODS: Video recording was used to collect data on the naturally occurring communication and interaction. Ten conscious and alert patients from two Norwegian ICUs were recruited. Two relatives and a total of sixty healthcare personnel participated. Content analysis was conducted, with focus on both the manifest and latent content meaning. RESULTS: We found a total of 66 situations in which patients attempted to attract the attention of others on their own initiative in order to express themselves. Attention-seeking actions, defined as the act of seeking attention and understanding without a voice, became an essential theme. Four patterns of interaction were identified: immediately responded to, delayed response or understanding, intensified attempts or giving up. Patients had a variety of reasons for seeking attention, which were classified into four domains: psychological expressions, physical expressions, social expressions and medical treatment. CONCLUSIONS: Patients' attention-seeking actions varied in content, form and the types of responses they elicited. The patients had to fight to first gain joint attention and then joint understanding. This was both energy-draining and time-consuming. RELEVANCE TO CLINICAL PRACTICE: Healthcare personnel need to spend more time for communication purposes, giving attention and being more alert to bodily or symbolic gestures to understand the patient's needs.

Patients' lived experience of intensive care when being on mechanical ventilation during the weaning process: A hermeneutic phenomenological study.

BACKGROUND: The medical and nursing care of the patient on mechanical ventilation has developed and proceeds in terms of ventilator functions, sedation strategies and patient participation. New data are needed to explore the weaning process from the patients' perspective. Therefore, the aim of this study was to explore the meaning of being a patient on mechanical ventilation during the weaning process in the intensive care unit. METHODS: This study used van Manen's hermeneutic phenomenological approach. Interviews were conducted, including twenty former intensive care patients from three different hospitals in Sweden. FINDINGS: Five themes emerged including thirteen related themes; Maintaining human dignity, Accepting the situation, Enduring the difficulties, Inadequate interaction and A sense of unreality. The experiences differed from each other and varied over time, and the same patient expressed both pleasant and unpleasant experiences. Weaning was not a separate experience but intertwined with that of being on mechanical ventilation in the intensive care unit. CONCLUSIONS: The patient's experiences differ and vary over time, with the same patient expressing various experiences. The favourable experiences were more clearly described, compared to previous research, this might depend on factors related to communication, participation and proximity to healthcare professionals and next-of-kin.

Terminal weaning or immediate extubation for withdrawing mechanical ventilation in critically ill patients (the ARREVE observational study).

PURPOSE: The relative merits of immediate extubation versus terminal weaning for mechanical ventilation withdrawal are controversial, particularly regarding the experience of patients and relatives. METHODS: This prospective observational multicentre study (ARREVE) was done in 43 French ICUs to compare terminal weaning and immediate extubation, as chosen by the ICU team. Terminal weaning was a gradual decrease in the amount of ventilatory assistance and immediate extubation was extubation without any previous decrease in ventilatory assistance. The primary outcome was posttraumatic stress symptoms (Impact of Event Scale Revised, IES-R) in relatives 3 months after the death. Secondary outcomes were complicated grief, anxiety, and depression symptoms in relatives; comfort of patients during the dying process; and job strain in staff. RESULTS: We enrolled 212 (85.5%) relatives of 248 patients with terminal weaning and 190 relatives (90.5%) of 210 patients with immediate extubation. Immediate extubation was associated with airway obstruction and a higher mean Behavioural Pain Scale score compared to terminal weaning. In relatives, IES-R scores after 3 months were not significantly different between groups (31.9 ± 18.1 versus 30.5 ± 16.2, respectively; adjusted difference, -1.9; 95% confidence interval, -5.9 to 2.1; p = 0.36); neither were there any differences in complicated grief, anxiety, or depression scores. Assistant nurses had lower job strain scores in the immediate extubation group. CONCLUSIONS: Compared to terminal weaning, immediate extubation was not associated with differences in psychological welfare of relatives when each method constituted standard practice in the ICU where it was applied. Patients had more airway obstruction and gasps with immediate extubation. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01818895.

Predictive Associations of Music, Anxiety, and Sedative Exposure on Mechanical Ventilation Weaning Trials.

BACKGROUND: Weaning from mechanical ventilation requires increased respiratory effort, which can heighten anxiety and later prolong the need for mechanical ventilation. OBJECTIVES: To examine the predictive associations of music intervention, anxiety, sedative exposure, and patients' characteristics on time to initiation and duration of weaning trials of patients receiving mechanical ventilation. METHODS: A descriptive, correlational design was used for a secondary analysis of data from a randomized trial. Music listening was defined as self-initiated, patient-directed music via headphones. Anxiety was measured daily with a visual analog scale. Sedative exposure was operationalized as a daily sedation intensity score and a sedative dose frequency. Analyses consisted of descriptive statistics, graphing, survival analysis, Cox proportional hazards regression, and linear regression. RESULTS: Of 307 patients, 52% were women and 86% were white. Mean age was 59.3 (SD, 14.4) years, mean Acute Physiology and Chronic Health Evaluation III score was 62.9 (SD, 21.6), mean duration of ventilatory support was 8 (range, 1-52) days, and mean stay in the intensive care unit was 18 (range, 2-71) days. Music listening, anxiety levels, and sedative exposure did not influence time to initial weaning trial or duration of trials. Clinical factors of illness severity, days of weaning trials, and tracheostomy placement influenced weaning patterns in this sample. CONCLUSIONS: Prospective studies of music intervention and other psychophysiological factors during weaning from mechanical ventilation are needed to better understand factors that promote successful weaning.

The breath of life. Patients' experiences of breathing during and after mechanical ventilation.

INTRODUCTION: Breathlessness is a prevalent and distressing symptom in intensive care, underestimated by nurses and physicians. Therefore, to develop a more comprehensive understanding of this problem, the study had two aims: to compare patients' self-reported scores of breathlessness obtained during mechanical ventilation (MV) with experiences of breathlessness later recalled by patients and: to explore the lived experience of breathing during and after MV. METHOD: A qualitatively driven sequential mixed method design combining prospective observational breathlessness data at the end of a spontaneous breathing trial (SBT) and follow up data from 11 post-discharge interviews. FINDINGS: Four out of six patients who reported breathlessness at the end of an SBT did not remember being breathless in retrospect. Experiences of breathing intertwined with the whole illness experience and were described in four themes: existential threat; the tough time; an amorphous and boundless body and getting through. CONCLUSION: Breathing was not always a clearly separate experience, but intertwined with the whole illness experience. This may explain the poor correspondence between patients' and clinicians assessments of breathlessness. The results suggest patients' own reports of breathing should form part of nursing interventions and follow-up to support patients' quest for meaning.

Patients' experience during weaning of invasive mechanical ventilation: A review of the literature. / Experiencias del paciente durante la retirada de la ventilación mecánica invasiva: una revisión de la literatura.

OBJECTIVE: Weaning from invasive mechanical ventilation (IMV) is influenced by physiological and psychological factors, the latter being the least studied. The aim was to identify, through the literature, patients' experiences during weaning from IMV and report its influencing factors. METHOD: The literature search was conducted using the Pubmed, CINAHL and PsycINFO databases. The search terms were: "patient", "experience" and "ventilator weaning". The research limits were: age (>19years) and language (English, Spanish and Finnish). RESULTS: Fifteen publications were analysed. The main results were grouped into three main categories according to patient's perceptions, feelings and experiences, influence of professionals' attention and determinants for successful weaning. Patients remember IMV weaning as a stressful process where they experience anxiety, frustration, despair or uncertainty. Nurses have a key role in improving communication with patients and foreseeing their needs. Family support and the care provided by the caregivers were shown as essential during the process. The patient's self-determination, self-motivation and confidence are identified as important factors to achieve successful IMV weaning. CONCLUSIONS: Psychological care, in addition to physical and technical care, is important at providing holistic care. Interventional studies are needed to improve the care during the weaning experience.

Music therapy, a review of the potential therapeutic benefits for the critically ill.

Intensive care units are a stressful milieu for patients, particularly when under mechanical ventilation which they refer to as inhumane and anxiety producing. Anxiety can impose harmful effects on the course of recovery and overall well-being of the patient. Resulting adverse effects may prolong weaning and recovery time. Music listening, widely used for stress release in all areas of medicine, tends to be a reliable and efficacious treatment for those critically ill patients. It can abate the stress response, decrease anxiety during mechanical ventilation, and induce an overall relaxation response without the use of medication. This relaxation response can lower cardiac workload and oxygen consumption resulting in more effective ventilation. Music may also improve sleep quality and reduce patient's pain with a subsequent decrease in sedative exposure leading to an accelerated ventilator weaning process and a speedier recovery.

Clinical study of midazolam sequential with dexmedetomidine for agitated patients undergoing weaning to implement light sedation in intensive care unit.

PURPOSE: To evaluate midazolam sequential with dexmedetomidine for agitated patients undergoing weaning to implement light sedation in ICU. METHODS: This randomized, prospective study was conducted in Tianjin Third Central Hospital, China. Using a sealed-envelope method, the patients were randomly divided into 2 groups (40 patients per group). Each patient of group A received an initial loading dose of midazolam at 0.3-3mg/kg·h 24 h before extubation, followed by an infusion of dexmedetomidine at a rate of 0.2-1 µg/kg·h until extubation. Each patient of group B received midazolam at a dose of 0.3-3 mg/kg·h until extubation. The dose of sedation was regulated according to RASS sedative scores maintaining in the range of -2-1. All patients were continuously monitored for 60 min after extubation. During the course, heart rate (HR), mean artery pressure (MAP), extubation time, adverse reactions, ICU stay, and hospital stay were observed and recorded continuously at the following time points: 24 h before extubation (T1), 12 h before extubation (T2), extubation (T3), 30 min after extubation (T4), 60 min after extubation (T5). RESULTS: Both groups reached the goal of sedation needed for ICU patients. Dexmedetomidine was associated with a significant increase in extubation quality compared with midazolam, reflected in the prevalence of delirium after extubation (20% (8/40) vs 45% (18/40)), respectively (p= 0.017). There were no clinically significant decreases in HR and MAP after infusing dexmedetomidine or midazolam. In the group A, HR was not significantly increased after extubation; however, in the group B, HR was significantly increased compared with the preextubation values (p < 0.05). HR was significantly higher in the group B compared with the group A at 30 and 60 min after extubation (both, p <0.05). Compared with preextubation values, MAP was significantly increased at extubation in the group B (p < 0.05) and MAP was significantly higher at T3, T4, T5 in the group B than group A (p < 0.05). There was a significant difference in extubation time ((3.0 ± 1.5) d vs (4.3 ± 2.2) d, p < 0.05), ICU stay ((5.4 ± 2.1) d vs (8.0 ± 1.4) d, p < 0.05), hospital stay ((10.1 ± 3.0) d vs (15.3 ± 2.6) d, p <0.05) between group A and B. CONCLUSION: Midazolam sequential with dexmedetomidine can reach the goal of sedation for ICU agitated patients, meanwhile it can maintain the respiratory and circulation parameters and reduce adverse reactions.

The influence of music during mechanical ventilation and weaning from mechanical ventilation: A review.

Mechanical ventilation (MV) causes many distressing symptoms. Weaning, the gradual decrease in ventilator assistance leading to termination of MV, increases respiratory effort, which may exacerbate symptoms and prolong MV. Music, a non-pharmacological intervention without side effects may benefit patients during weaning from mechanical ventilatory support. A narrative review of OVID Medline, PsychINFO, and CINAHL databases was conducted to examine the evidence for the use of music intervention in MV and MV weaning. Music intervention had a positive impact on ventilated patients; 16 quantitative and 2 qualitative studies were identified. Quantitative studies included randomized clinical trials (10), case controls (3), pilot studies (2) and a feasibility study. Evidence supports music as an effective intervention that can lesson symptoms related to MV and promote effective weaning. It has potential to reduce costs and increase patient satisfaction. However, more studies are needed to establish its use during MV weaning.

Weaning from mechanical ventilation: a scoping review of qualitative studies.

BACKGROUND: Weaning from mechanical ventilation is influenced by patient, clinician, and organizational factors. OBJECTIVE: To identify factors that may influence weaning and adoption of weaning strategies and tools, clinicians' perceptions of weaning strategies, and weaning experiences of patients and patients' families. METHOD: A scoping review of indexed and nonindexed publications (1990-2012) was done. Qualitative studies of health care providers, patients, and patients' families involved in weaning were included. Two investigators independently screened 8350 publications and extracted data from 43 studies. Study themes were content analyzed to identify common categories and themes within the categories. RESULTS: The study sample consisted of nurses in 15 studies, nurses and patients in 1 study, various health care providers in 11, patients in 10, and physicians in 4. Categories identified were as follows: for nurses, role or scope of practice, informing decision making, and influence on weaning outcome; for health care providers, factors influencing weaning decisions or use of protocols, role or scope of practice related to weaning, and organizational structure or practice environment; for patients, experience of mechanical ventilation and weaning, experience of the intensive care environment, psychological phenomena, and enabling success in weaning; and for physicians, tools or factors to facilitate weaning decisions and perceptions of nurses' role and scope of practice. CONCLUSIONS: Important issues identified were perceived importance of interprofessional collaboration and communication, need to combine subjective knowledge of the patient with objective clinical data, balancing of weaning systematization with individual needs, and appreciation of the physical and psychological work of weaning.

Perceived decisional responsibility for mechanical ventilation and weaning: a Norwegian survey.

AIM: To explore variability in perceptions of nurse managers and physician directors regarding roles, responsibilities and clinical-decision making related to mechanical ventilator weaning in Norwegian intensive care units (ICUs). BACKGROUND: Effective teamwork is crucial for providing optimal patient care in ICU. More knowledge on nurses' and physicians' perceptions of responsibility in clinical decision-making for mechanical ventilation is needed. METHODS: Self-administered survey of mechanical ventilation and weaning responsibilities was sent to nurse managers and physician directors of Norwegian adult ICUs. Nurses' decisional influence and autonomy were estimated on a numeric rating scale (NRS) from 0 to 10 (least to most). RESULTS: Response rate was 38/60 (63%) nurses and 38/52 (73%) physicians. On the NRS nurse managers perceived the autonomy and influence of nurses' ventilator decisions higher than physician directors: median of 7 (IQR 5-8) (nurses) versus 5 (3-6) (physicians), (p < 0·01), and 8 (7-9) (nurses) versus 7 (5-8) (physicians), (p < 0·01) respectively. Respondents agreed that nurses collaborated in assessment of patient response to ventilator changes and titrating ventilator settings: 92% of nurses and 87% of physicians, (p = 0·46), and recognizing weaning failure 84% of nurses and 84% of physicians, (p = 0·96). Physician directors perceived significantly less collaborative decision-making on weaning method (p = 0·01), weaning readiness (p = 0·04) and readiness to extubate (p < 0·01) than nurse managers. Both groups acknowledged the importance of 'knowing the patient' for weaning success, and agreed that the assessment of work of breathing, well-being, and clinical deterioration were important for determining weaning tolerance. CONCLUSIONS: Nurse managers perceived nurses to have greater autonomy, influence and collaborative interaction regarding decisions on mechanical ventilation than physician directors. Greater awareness and acknowledgment of nurses' role may promote interprofessional collaboration and improve patient care.

The experiences of adult ventilator-dependent patients: a meta-synthesis review.

Studies exploring the perceptions of patients whose lives are maintained by mechanical ventilation highlight the stressful nature of this type of experience. The objective of this meta-synthesis study was to describe the nature of the experience of adult ventilator-dependent patients. A systematic literature search of English and Chinese databases was undertaken, covering the period between 1970 and 2012. Qualitative research findings were extracted and pooled using the Joanna Briggs Institute Qualitative Assessment and Review Instrument. A total of 1004 papers were identified from various database and hand searches. Nineteen papers were critically appraised and 16 met inclusion criteria. Five meta-synthesis themes emerged from the analysis: (1) the feelings of fear due to being dependent on a ventilator and the loss of control of life; (2) disconnection with reality; (3) impaired embodiment; (4) construction of coping patterns; (5) trust and caring relationship. Suggested implications for practice include enhancing the trust relationship with health professionals, as well as nursing actions throughout the suction procedure relating to release of patient's psychological distress and empowering their resilience factors.

Anaesthetists' perceptions of facilitative weaning strategies from mechanical ventilator in the intensive care unit (ICU): a qualitative interview study.

AIM: This study aimed to examine anaesthetists' perceptions of facilitative weaning from the mechanical ventilator in the intensive care unit (ICU). METHODS: Explorative qualitative interviews in a phenomenographic reference frame with a purposive sample of 14 eligible anaesthetists from four different ICUs with at least one year of clinical experience of ICU and of ventilator weaning. FINDINGS: Four categories of anaesthetists' perceptions of facilitative decision-making strategies for ventilator weaning were identified. These were the instrumental, the interacting, the process-oriented and the structural strategies" for ventilator weaning. The findings refer to a supportive multidisciplinary holistic ICU quality of care. Choice of strategy for ventilator weaning was flexible and individually tailored to the patients'. CONCLUSIONS: Choice of strategy was flexible and individually adjustable. Introduction of evidence-based guidelines from ventilator weaning is necessary in the ICU. The guidelines should also cover the responsibilities of various professional groups. Regular evaluations of methods and strategies used in practice need to be implemented. This may facilitate decision-making strategies for ventilator weaning in practice at the ICU. Greater attention needs to focus on family members' experiences. The strategies should be an integral part of continuous staff training.

Anxiety and agitation in mechanically ventilated patients.

During an ethnography conducted in an intensive care unit (ICU), we found that anxiety and agitation occurred frequently and were important considerations in the care of 30 patients weaning from prolonged mechanical ventilation. We conducted a secondary analysis to (a) describe characteristics of anxiety and agitation experienced by mechanically ventilated patients, (b) explore how clinicians recognized and interpreted anxiety and agitation, and (c) describe strategies and interventions used to manage anxiety and agitation with mechanically ventilated patients. We constructed the Anxiety/Agitation in Mechanical Ventilation Model to illustrate the multidimensional features of symptom recognition and management. Patients' ability to interact with the environment served as a basis for identification and management of anxiety or agitation. Clinicians' attributions about anxiety or agitation, and "knowing the patient," contributed to their assessment of patient responses. Clinicians chose strategies to overcome either the stimulus or the patient's appraisal of risk of the stimulus. This article contributes to the body of knowledge about symptom recognition and management in the ICU by providing a comprehensive model to guide future research and practice.

Psychophysiological determinants of repeated ventilator weaning failure: an explanatory model.

BACKGROUND: The adverse effects of a failed ventilator weaning trial on the subsequent weaning attempts are not well understood. OBJECTIVES: To examine physiological and psychological factors that may be predictive of risk for repeated weaning failures and prolonged mechanical ventilation. METHODS: A prospective predictive study of 102 subjects, age 34 to 91 years, whose first ventilator weaning trial was unsuccessful but who were physiologically ready for another weaning attempt. Subjects were recruited from intensive care units and a respiratory care center of a tertiary medical center. Validated self-report scales and a Bicore monitoring system were used to measure ventilator patients' psychophysiological performance during the second weaning trial. Structural equation modeling was used to analyze the data and test the model. RESULTS: Significant causal pathways were found between fear and anxiety (r = 0.77; P < .001), anxiety and respiratory function (r = 0.24; P < .05), and respiratory function and weaning outcomes (r = 0.42; P < .001). The overall model predicted that both physiological and psychological factors were important in determining repeated failure of ventilator weaning, and the data were in support of the model (χ(2) = 29.49, P > .05). CONCLUSIONS: Patients whose first ventilator weaning trial is unsuccessful may be markedly fearful. Left unaddressed, these fears cause high anxiety levels that significantly compromise respiratory function and contribute to subsequent weaning failures. Thus begins a vicious cycle of repeated failure of ventilator weaning and prolonged mechanical ventilation.

Wash and wean: bathing patients undergoing weaning trials during prolonged mechanical ventilation.

BACKGROUND: Bathing is a fundamental nursing care activity performed for or with the self-assistance of critically ill patients. Few studies address caregiver or patient-family perspectives about bathing activity during weaning from prolonged mechanical ventilation (PMV). OBJECTIVE: To describe practices and beliefs about bathing patients during weaning from PMV. METHODS: Secondary analysis of qualitative data (observational field notes, interviews, and clinical record review) from a larger ethnographic study involving 30 patients weaning from PMV and the clinicians who cared for them using basic qualitative description. RESULTS: Bathing, hygiene, and personal care were highly valued and equated with "good" nursing care by families and nurses. Nurses and respiratory therapists reported "working around" bath time and promoted conducting weaning trials before or after bathing. Patients were nevertheless bathed during weaning trials despite clinicians' expressed concerns for energy conservation. Clinicians recognized individual patient response to bathing during PMV weaning trials. CONCLUSION: Bathing is a central care activity for patients on PMV and a component of daily work processes in the intensive care unit. Bathing requires assessment of patient condition and activity tolerance and nurse-respiratory therapist negotiation and accommodation with respect to the initiation or continuation of PMV weaning trials during bathing. Further study is needed to validate the impact (or lack of impact) of various timing strategies for bathing patients who are on PMV.

Beneficial effects of loxapine on agitation and breathing patterns during weaning from mechanical ventilation.

INTRODUCTION: Interruption of sedation during weaning from mechanical ventilation often leads to patient agitation because of withdrawal syndrome. We tested the short-term efficacy and tolerance of loxapine in this situation. METHODS: Nineteen mechanically ventilated patients with marked agitation after sedation withdrawal were included. Three agitation scales, the Richmond Agitation Sedation Scale (RASS), the Motor Activity Assessment Scale (MAAS), and the Ramsay and physiological variables (respiratory rate, airway occlusion pressure during the first 0.1 second of inspiration (P0.1), heart rate and systolic arterial blood pressure) were recorded before and after loxapine administration. RESULTS: Loxapine dramatically improved all agitation scores (RASS and MASS decreased from 2 +/- 0 to -1.1 +/- 2.3, and 5.4 +/- 0.5 to 2.7 +/- 1.6, respectively; Ramsay increased from 1.0 +/- 0 to 3.5 +/- 1.5, 60 minutes after loxapine administration, P < 0.05 for all scores) as well as P0.1 (6 +/- 4.2 to 1.8 +/- 1.8 cm H2O; P < 0.05) and respiratory rate (from 31.2 +/- 7.2 to 23.4 +/- 7.8; P < 0.05) without hemodynamic adverse events. No side effects occurred. Sixteen (84%) patients were successfully managed with loxapine, sedation was resumed in two others, and one patient self-extubated without having to be reintubated. CONCLUSIONS: Loxapine was safe and effective in treating agitation in a small group of mechanically ventilated patients and improved respiratory physiologic parameters, enabling the weaning process to be pursued. A multicenter trial is under way to confirm these promising results.

Depressive disorders during weaning from prolonged mechanical ventilation.

PURPOSE: Patients who require mechanical ventilation are at risk of emotional stress because of total dependence on a machine for breathing. The stress may negatively impact ventilator weaning and survival. The purpose of this study was to determine whether depressive disorders in patients being weaned from prolonged mechanical ventilation are linked to weaning failure and decreased survival. METHODS: A prospective study of 478 consecutive patients transferred to a long-term acute care hospital for weaning from prolonged ventilation was undertaken. A clinical psychologist conducted a psychiatric interview to assess for the presence of depressive disorders. RESULTS: Of the 478 patients, 142 had persistent coma or delirium and were unable to be evaluated for depressive disorders. Of the remaining 336 patients, 142 (42%) were diagnosed with depressive disorders. In multivariate analysis, co-morbidity score [odds ratio (OR), 1.23; P = 0.007], functional dependence before the acute illness (OR, 1.70, P = 0.03) and history of psychiatric disorders (OR, 3.04, P = 0.0001) were independent predictors of depressive disorders. The rate of weaning failure was higher in patients with depressive disorders than in those without such disorders (61 vs. 33%, P = 0.0001), as was mortality (24 vs. 10%, P = 0.0008). The presence of depressive disorders was independently associated with mortality (OR, 4.3; P = 0.0002); age (OR, 1.06; P = 0.001) and co-morbidity score (OR, 1.24; P = 0.02) also predicted mortality. CONCLUSION: Depressive disorders were diagnosed in 42% of patients who were being weaned from prolonged ventilation. Patients with depressive disorders were more likely to experience weaning failure and death.