Long-term survival and functional outcomes of critically ill patients with hematologic malignancies: a Canadian multicenter prospective study

PURPOSE

Patients with hematologic malignancy (HM) commonly develop critical illness. Their long-term survival and functional outcomes have not been well described.

METHODS

We conducted a prospective, observational study of HM patients admitted to seven Canadian intensive care units (ICUs) (2018-2020). We followed survivors at 7 days, 6 months and 12 months following ICU discharge. The primary outcome was 12-month survival. We evaluated functional outcomes at 6 and 12 months using the functional independent measure (FIM) and short form (SF)-36 as well as variables associated with 12-month survival.

RESULTS

We enrolled 414 patients including 35% women. The median age was 61 (interquartile range, IQR: 52-69), median Sequential Organ Failure Assessment (SOFA) score was 9 (IQR: 6-12), and 22% had moderate-severe frailty (clinical frailty scale [CFS] ≥ 6). 51% had acute leukemia, 38% lymphoma/multiple myeloma, and 40% had received a hematopoietic stem cell transplant (HCT). The most common reasons for ICU admission were acute respiratory failure (50%) and sepsis (40%). Overall, 203 (49%) were alive 7 days post-ICU discharge (ICU survivors). Twelve-month survival of the entire cohort was 21% (43% across ICU survivors). The proportion of survivors with moderate-severe frailty was 42% (at 7 days), 14% (6 months), and 8% (12 months). Median FIM at 7 days was 80 (IQR: 50-109). Physical function, pain, social function, mental health, and emotional well-being were below age- and sex-matched population scores at 6 and 12 months. Frailty, allogeneic HCT, kidney injury, and cardiac complications during ICU were associated with lower 12- month survival.

CONCLUSIONS

49% of all HM patients were alive at 7 days post-ICU discharge, and 21% at 12 months. Survival varied based upon hematologic diagnosis and frailty status. Survivors had important functional disability and impairment in emotional, physical, and general well-being.

Clinical diagnostic accuracy of respiratory failure in critically ill hematopoietic stem cell transplant patients

RATIONALE

Acute respiratory failure (ARF) is a frequent complication following hematopoietic cell transplantation (HCT). We aimed to characterize the etiologies of ARF in patients who died in the intensive care unit following HCT based on autopsy findings. We then evaluated agreement between the clinical and pathologic diagnosis.

METHODS

We performed a chart review of all HCT patients who died and underwent autopsy in our ICU between 2006-2016. We evaluated the presumed clinical diagnosis and confidence in the diagnosis by chart review, the pathologic diagnosis on autopsy, and whether the clinical-pathologic diagnoses were concordant. When there was discordance, we evaluated whether knowledge of the pathology could have changed management.

RESULTS

Thirteen patients underwent autopsy after dying. Infection was the presumed cause in 11/13 cases. The clinical and pathologic diagnoses were concordant in 6/13(46%). In the seven discordant cases (all clinically diagnosed as infection), autopsy revealed two non-infectious inflammatory causes, one post-transplant lymphoproliferative disorder, and three non-bacterial infectious etiology. Pathologic findings may have changed management in 7/13(54%) cases.

CONCLUSIONS

In a subset of HCT-recipients who died from respiratory failure, discordance was frequent between clinical and pathologic diagnoses. The risks and benefits of obtaining tissue to improve our diagnostic accuracy requires further evaluation.

Severe Hyponatremia and Seizure From Peripheral Infusion of Norepinephrine Diluted in Dextrose 5% in Water: A Case Report

Recent studies have demonstrated that vasopressors can be delivered safely through peripheral intravenous lines. While norepinephrine is usually delivered at a concentration of 16 to 32 μg/mL, out of concern for extravasation and interstitial necrosis, some patients receive more dilute norepinephrine solutions through peripheral intravenous catheters. We describe a case of severe hyponatremia and seizure resulting from administration of norepinephrine concentrated at 4 μg/mL in dextrose 5% in water. After the incident, the institutional policy changed to recommend normal saline as the default diluent for peripheral norepinephrine, with a more concentrated option available. The incident also informed similar guidelines at other hospitals.

Feasibility of melatonin for prevention of delirium in critically ill patients: a protocol for a multicentre, randomised, placebo-controlled study

INTRODUCTION

Delirium is highly prevalent in the intensive care unit (ICU) and is associated with adverse clinical outcomes. At this time, there is no drug that effectively prevents delirium in critically ill patients. Alterations in melatonin secretion and metabolism may contribute to the development of delirium. Administration of exogenous melatonin has been shown to prevent delirium in non-critically ill surgical and medical patients. This trial will demonstrate the feasibility of a planned multicentre, randomised controlled trial to test the hypothesis that melatonin can prevent delirium in critically ill patients compared with placebo.

METHODS AND ANALYSIS

This feasibility trial is a randomised, 3-arm, placebo-controlled study of melatonin (2 vs 0.5 mg vs placebo, administered for a maximum of 14 days) for the prevention of delirium in critically ill patients. A total of 69 patients aged 18 years and older with an expected ICU length of stay >48 hours will be recruited from 3 Canadian ICUs. The primary outcome is protocol adherence (ie, overall proportion of study drug doses administered in the prescribed administration window). Secondary outcomes include pharmacokinetic parameters, incidence, time to onset, duration of delirium, number of delirium-free days, adverse events, self-reported sleep quality, rest-activity cycles measured by wrist actigraphy, duration of mechanical ventilation, ICU length of stay and mortality. Data will be analysed using an intention-to-treat approach.

ETHICS AND DISSEMINATION

The study has been approved by Health Canada and the research ethics board of each study site. Trial results will be presented at international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT02615340: Pre-results.

Mechanical ventilation during extracorporeal life support (ECLS): a systematic review

PURPOSE

In patients with acute respiratory distress syndrome (ARDS), extracorporeal life support (ECLS) has been utilized to support gas exchange and mitigate ventilator-induced lung injury (VILI). The optimal ventilation settings while on ECLS are unknown. The purpose of this systematic review is to describe the ventilation practices in patients with ARDS who require ECLS.

METHODS

We electronically searched MEDLINE, EMBASE, CENTRAL, AMED, and HAPI (inception to January 2015). Studies included were randomized controlled trials, observational studies, or case series (≥4 patients) of ARDS patients undergoing ECLS. Our review focused on studies describing ventilation practices employed during ECLS for ARDS.

RESULTS

Forty-nine studies (2,042 patients) met our inclusion criteria. Prior to initiation of ECLS, at least one parameter consistent with injurious ventilation [tidal volume >8 mL/kg predicted body weight (PBW), peak pressure >35 cmH2O (or plateau pressure >30 cmH2O), or FiO2 ≥0.8] was noted in 90% of studies. After initiation of ECLS, studies reported median [interquartile range (IQR)] reductions in: tidal volume [2.4 mL/kg PBW (2.2-2.9)], plateau pressure [4.3 cmH2O (3.5-5.8)], positive end-expiratory pressure (PEEP) [0.20 cmH2O (0-3.0)], and FiO2 [0.40 (0.30-0.60)]. Median (IQR) overall mortality was 41 % (31-51%).

CONCLUSIONS

Reduction in the intensity of mechanical ventilation in patients with ARDS supported by ECLS is common, suggesting that clinicians may be focused on reducing VILI after ECLS initiation. Future investigations should focus on establishing the optimal ventilatory strategy for patients with ARDS who require ECLS.