Sedation in mechanically ventilated patients-time to stay awake?

Delirium screening tools in the post-anaesthetic care unit: a systematic review and meta-analysis

BACKGROUND

Delirium is a serious neurocognitive disorder among surgical patients in the post-anaesthetic care unit (PACU). Despite the development of screening tools to identify delirium, it is not clear which tool is the most accurate and reliable in assessing delirium in the PACU.

AIM

To examine the diagnostic accuracy of delirium screening tools used in the PACU.

METHODS

A systematic literature search of CINAHL, MEDLINE, Embase, PsycINFO and Scopus was conducted, using MeSH terms and relevant keywords, from databases establishment to 23 April 2021. Studies were assessed for methodological quality using the Standards for Reporting of Diagnostic Accuracy Studies (STARD) tool.

RESULTS

A total of 1503 studies were screened from the database search, four studies met the inclusion criteria for this review. Six delirium screening tools used in the PACU were identified in the selected studies. Three studies evaluated screening tools in adult surgical patients without cognitive impairment and dementia. Two studies evaluated screening tools among patients who were scheduled for elective surgery. Review results indicated that two tools, the 4A's test (4AT; sensitivity 96%; specificity 99%) and the 3 min diagnostic interview for the Confusion Assessment Method (3D-CAM; sensitivity 100%; specificity 88%), had greatest validity and reliability as a screening tool for detecting delirium in the PACU.

CONCLUSION

Results indicate the 4AT and the 3D-CAM are most accurate screening tools to detect delirium in the PACU. Further research is required to validate those tools among a broader surgical population, including patients with cognitive impairment, dementia and those undergoing emergency surgical procedures.

The Susceptibility of MDR-K. Pneumoniae To Polymyxin B Plus Its Nebulised Form Versus Polymyxin B Alone in Critically Ill South Asian Patients

Introduction

Critically ill patients in intensive care units are at high risk of dying not only from the severity of their illness but also from secondary causes such as hospital-acquired infections. USA national medical record-data show that approximately 10% of patients on mechanical ventilation in an intensive care unit developed ventilator-associated pneumonia. Polymyxin B has been used intravenously in the treatment of multi-drug resistant gram-negative infections, either as a monotherapy or with other potentially effective antibiotics, and the recent international guidelines have emphasised the use of nebulised polymyxin B together with intravenous polymyxin B to gain the optimum clinical outcome in ventilator-associated pneumonia cases caused by multi-drug resistant gram-negative infections.

Methods

One hundred and seventy-eight patients with ventilator-associated pneumonia due to multi-drug resistant K. pneumoniae were identified during the study period. Following the inclusion and exclusion criteria, 121 patients were enrolled in the study and randomly allocated to two study groups. Group 1 patients were treated with intravenous Polymyxin B plus nebulised polymyxin B (n=64) and Group 2 patients with intravenous Polymyxin B alone (n=57). The study aimed to compare the use of Polymyxin B plus its nebulised form to polymyxin B alone, in the treatment of MDR-K. pneumoniae associated ventilator-associated pneumonia in critically ill patients.

Results

In Group 1, a complete clearance of K. pneumoniae was found in fifty-nine patients (92.1%; n=64) compared to forty patients (70.1%, n=57) in the Group 2 (P<0.003). The average time till extubation was significantly higher in Group 2 compared to Group 1 (P<0.05). The total length-of-stay in the ICU was significantly higher in Group 2 compared to Group 1. (P<0.05). These results support the view that the Polymyxin B dual-route regime may be considered as an appropriate antibiotic therapy, in critically ill South Asian patients with ventilator-associated pneumonia.

Neurologic Assessment of the Neurocritical Care Patient

Sedation is a ubiquitous practice in ICUs and NCCUs. It has the benefit of reducing cerebral energy demands, but also precludes an accurate neurologic assessment. Because of this, sedation is intermittently stopped for the purposes of a neurologic assessment, which is termed a neurologic wake-up test (NWT). NWTs are considered to be the gold-standard in continued assessment of brain-injured patients under sedation. NWTs also produce an acute stress response that is accompanied by elevations in blood pressure, respiratory rate, heart rate, and ICP. Utilization of cerebral microdialysis and brain tissue oxygen monitoring in small cohorts of brain-injured patients suggests that this is not mirrored by alterations in cerebral metabolism, and seldom affects oxygenation. The hard contraindications for the NWT are preexisting intracranial hypertension, barbiturate treatment, status epilepticus, and hyperthermia. However, hemodynamic instability, sedative use for primary ICP control, and sedative use for severe agitation or respiratory distress are considered significant safety concerns. Despite ubiquitous recommendation, it is not clear if additional clinically relevant information is gleaned through its use, especially with the contemporaneous utilization of multimodality monitoring. Various monitoring modalities provide unique and pertinent information about neurologic function, however, their role in improving patient outcomes and guiding treatment plans has not been fully elucidated. There is a paucity of information pertaining to the optimal frequency of NWTs, and if it differs based on type of injury. Only one concrete recommendation was found in the literature, exemplifying the uncertainty surrounding its utility. The most common sedative used and recommended is propofol because of its rapid onset, short duration, and reduction of cerebral energy requirements. Dexmedetomidine may be employed to facilitate serial NWTs, and should always be used in the non-intubated patient or if propofol infusion syndrome (PRIS) develops. Midazolam is not recommended due to tissue accumulation and residual sedation confounding a reliable NWT. Thus, NWTs are well-tolerated in selected patients and remain recommended as the gold-standard for continued neuromonitoring. Predicated upon one expert panel, they should be performed at least one time per day. Propofol or dexmedetomidine are the main sedative choices, both enabling a rapid awakening and consistent NWT.

Understanding patients' experiences of being mechanically ventilated in the Intensive Care Unit: Findings from a meta-synthesis and meta-summary

AIMS AND OBJECTIVES

To synthesise the evidence reported in qualitative studies concerning the lived experiences of adult patients receiving mechanical ventilation in Intensive Care Unit (ICU).

BACKGROUND

Critically ill patients receiving mechanical ventilation in the ICU have been reported to suffer from severe physical and emotional responses such as hopelessness, anxiety, high levels of frustration and stress. Recent improvements in the field of mechanical ventilation and sedative medications as experienced by patients that can inform nursing care have not been summarised to date.

DESIGN

A systematic review of qualitative studies followed by a meta-synthesis and a meta-summary was performed.

METHODS

Four electronic databases were searched by two authors in June 2019. A total of nine studies were included and evaluated based on their methodological quality using the Critical Appraisal Skills Programme checklist.

RESULTS

A total of 24 codes emerged from the abstraction process, which were categorised into 11 categories and four themes: (a) "The effect of the intense stress on the body's systems," (b) "The induced negative emotional situations," (c) "The feeling of being cared for in a hospital setting" and (d) "The perceived support from the family and loved ones." Furthermore, the most frequent codes across studies were "Being afraid," "Feeling supervised," "Feeling comforted," "Failing to communicate," and "Experiencing difficulties in breathing," with an intensity of 66.6%.

CONCLUSION

Patients receiving mechanical ventilation have expressed a general sense of vulnerability, of which critical care nurses need to be aware.

RELEVANCE TO CLINICAL PRACTICE

Findings suggest the need for improvements at the nursing, unit, educational and policy levels; furthermore, more research is also required at the international levels given the current trends towards no sedation protocols for the management of ICU patients: listening to their experiences becomes imperative, in order to ensure an awake, comfortable and ventilator-tolerant patient.

Negotiated mobilisation: An ethnographic exploration of nurse-patient interactions in an intensive care unit

AIMS AND OBJECTIVES

To explore nurse-patient interactions in relation to the mobilisation of nonsedated and awake, mechanically ventilated patients in the intensive care unit.

BACKGROUND

Lighter sedation has enabled the early mobilisation of mechanically ventilated patients, but little is known about the nurses' role and interaction with critically ill patients in relation to mobilisation.

DESIGN AND METHODS

The study had a qualitative design using an ethnographic approach within the methodology of interpretive description. Data were generated in two intensive care units in Denmark, where a strategy of no sedation was applied. Participant observation was conducted during 58 nurse-patient interactions in relation to mobilisation between nurses (n = 44) and mechanically ventilated patients (n = 25). We conducted interviews with nurses (n = 16) and patients (n = 13) who had been mechanically ventilated for at least 3 days. The data were analysed using inductive, thematic analysis. The report of the study adhered to the COREQ checklist.

FINDING

We identified three themes: "Diverging perspectives on mobilisation" showed that nurses had a long-term and treatment-oriented perspective on mobilisation, while patients had a short-term perspective and regarded mobilisation as overwhelming in their present situation. "Negotiation about mobilisation" demonstrated how patients actively negotiated the terms of mobilisation with the nurse. "Inducing hope through mobilisation" captured how nurses encouraged mobilisation by integrating aspects of the patient's daily life as a way to instil hope for the future.

CONCLUSIONS

Exploring the nurse-patient interactions illustrated that mobilisation is more than physical activity. Mobilisation is accomplished through nurse-patient collaborations as a negotiated, complex and meaningful achievement, which is driven by the logic of care, leading to hope for the future.

RELEVANCE TO CLINICAL PRACTICE

The study demonstrated the important role of nurses in achieving mobilisation in collaboration and through negotiation with mechanically ventilated patients in the intensive care unit.