Interfacility transfer of the critically ill: Transfer status does not influence survival

PURPOSE

To estimate differences in case-mix adjusted hospital mortality between adult ICU patients who are transferred during their ICU-stay and those who are not.

METHODS

19,260 visits to 12 ICUs in Nova Scotia (NS), Canada April 2018-September 2023 were analyzed. Data were obtained from the NS Provincial ICU database. Generalized additive models (GAMs) were used to estimate differences in case-mix adjusted hospital mortality between patients who underwent transfer and those who did not.

RESULTS

1040/19,260 (5%) ICU visits involved interfacility-transfer. No difference in hospital mortality was identified between transferred and non-transferred patients by GAM (OR, 0.99, 95% CI, 0.82 to 1.19; p = 0.91). No mortality difference was observed between patients undergoing a single transfer versus multiple (OR, 0.87; 95% CI, 0.45 to -1.69; p = 0.68). A GAM including the categories no transfer, one transfer, and multiple transfers identified a difference in hospital mortality for patients that underwent multiple transfers compared to non-transferred patients (OR, 0.68; 95% CI, 0.46 to 1.00, p = 0.05), but no difference was identified in a post-hoc matched cohort sensitivity analysis (OR, 0.68; 95% CI, 0.46 to 1.01, p = 0.05).

CONCLUSION

The transfer of critically ill patients between ICUs in Nova Scotia did not impact case-mix adjusted hospital mortality.

Intensive Care Unit Without Walls

Critical illness is a continuum with different phases and trajectories. The "Intensive Care Unit (ICU) without walls" concept refers to a model whereby care is adjusted in response to the patient's needs, priorities, and preferences at each stage from detection, escalation, early decision making, treatment and organ support, followed by recovery and rehabilitation, within which all healthcare staff, and the patient are equal partners. The rapid response system incorporates monitoring and alerting tools, a multidisciplinary critical care outreach team and care bundles, supported with education and training, analytical and governance functions, which combine to optimise outcomes of critically ill patients, independent of location.

Comparison of venovenous extracorporeal membrane oxygenation, prone position and supine mechanical ventilation for severely hypoxemic acute respiratory distress syndrome: a network meta-analysis

PURPOSE

Severe acute respiratory distress syndrome (ARDS) with PaO2/FiO2 < 80 mmHg is a life-threatening condition. The optimal management strategy is unclear. The aim of this meta-analysis was to compare the effects of low tidal volumes (Vt), moderate Vt, prone ventilation, and venovenous extracorporeal membrane oxygenation (VV-ECMO) on mortality in severe ARDS.

METHODS

We performed a frequentist network meta-analysis of randomised controlled trials (RCTs) with participants who had severe ARDS and met eligibility criteria for VV-ECMO or had PaO2/FiO2 < 80 mmHg. We applied the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology to discern the relative effect of interventions on mortality and the certainty of the evidence.

RESULTS

Ten RCTs including 812 participants with severe ARDS were eligible. VV-ECMO reduces mortality compared to low Vt (risk ratio [RR] 0.77, 95% confidence interval [CI] 0.59-0.99, moderate certainty) and compared to moderate Vt (RR 0.75, 95% CI 0.57-0.98, low certainty). Prone ventilation reduces mortality compared to moderate Vt (RR 0.78, 95% CI 0.66-0.93, high certainty) and compared to low Vt (RR 0.81, 95% CI 0.63-1.02, moderate certainty). We found no difference in the network comparison of VV-ECMO compared to prone ventilation (RR 0.95, 95% CI 0.72-1.26), but inferences were based solely on indirect comparisons with very low certainty due to very wide confidence intervals.

CONCLUSIONS

In adults with ARDS and severe hypoxia, both VV-ECMO (low to moderate certainty evidence) and prone ventilation (moderate to high certainty evidence) improve mortality relative to low and moderate Vt strategies. The impact of VV-ECMO versus prone ventilation remains uncertain.

Metabolic support for patients on extra-corporeal membrane oxygenation

PURPOSE OF REVIEW

The purpose of the review is to summarize recent research on metabolic support during extracorporeal membrane oxygenation. In this review, we cover the evidence on nutritional supplementation, both the route of supplementation, timing of initiation of supplementation as well as quantities of supplementation needed. In addition, we discuss the recent trend in awake extracorporeal membrane oxygenation (ECMO) and its benefits to patients.

RECENT FINDINGS

As ECMO use continues to increase over the last few years, for both cardiovascular as well as respiratory failure, the need to optimize the metabolic states of patients has arisen. Increasing evidence has pointed towards this hitherto unexplored domain of patient care having a large impact on outcomes. Additionally, strategies such as awake ECMO for select patients has allowed them to preserve muscle mass which could aid in a faster recovery.

SUMMARY

There is a role of optimal metabolic support in the early recovery of patients on ECMO that is currently under-recognized. Future directions of research that aim to improve post ECMO outcomes must focus on this area.

Targeting Hypercapnia in Chronic Lung Disease and Obesity Hypoventilation: Benefits and Challenges

Hypoventilation is a complication that is not uncommon in chronic obstructive pulmonary disease and calls for both medical treatment of the underlying disease and, frequently, noninvasive ventilation either during exacerbations requiring hospitalization or in a chronic state in the patient at home. Obesity hypoventilation syndrome by definition is associated with ventilatory failure and hypercapnia. It may or may not be accompanied by obstructive sleep apnea, which when detected becomes an additional target for positive airway pressure treatment. Intensive research has not completely resolved the best choice of treatment, and the simplest modality, continuous positive airway pressure, may still be entertained.

Review article: The epidemiology and management of Clostridioides difficile infection-A clinical update

BACKGROUND

Clostridioides difficile is the most common cause of healthcare-associated infection, and severe cases can result in significant complications. While anti-microbial therapy is central to infection management, adjunctive therapies may be utilised as preventative strategies.

AIM

This article aims to review updates in the epidemiology, diagnosis, and management, including treatment and prevention, of C. difficile infections.

METHODS

A narrative review was performed to evaluate the current literature between 1986 and 2023.

RESULTS

The incidence of C. difficile infection remains significantly high in both hospital and community settings, though with an overall decline in recent years and similar surveillance estimates globally. Vancomycin and fidaxomicin remain the first line antibiotics for treatment of non-severe C. difficile infection, though due to lower recurrence rates, infectious disease society guidelines now favour use of fidaxomicin. Faecal microbiota transplantation should still be considered to prevent recurrent C. difficile infection. However, in the past year the field has had a significant advancement with the approval of the first two live biotherapeutic products-faecal microbiota spores-live brpk, an oral capsule preparation, and faecal microbiota live-jslm-both indicated for the prevention of recurrent C. difficile infection, with additional therapies on the horizon.

CONCLUSION

Although the prevalence of C. difficile infection remains high, there have been significant advances in the development of novel therapeutics and preventative measures following changes in recent practice guidelines, and will continue to evolve in the future.

A randomised clinical trial of awake prone positioning in COVID-19 suspects with acute hypoxemic respiratory failure

Background

Awake prone position (APP) has been reported to improve oxygenation in patients with COVID-19 disease and to reduce the requirement for invasive mechanical ventilation for patients requiring support with high flow nasal cannula. There is conflicting data for patients requiring lower-level oxygen support.

Research question

Does APP reduce escalation of oxygen support in COVID-19 patients requiring supplementary oxygen?The primary outcome was defined as an escalation of oxygen support from simple supplementary oxygen (NP, HM, NRB) to NIV (CPAP or BiPAP), HFNC or IMV; OR from NIV (CPAP or BiPAP) or HFNC to IMV by day30.

Study design

Two center, prospective, non-blind, randomised controlled trial. Patients with confirmed or suspected COVID-19 pneumonia requiring ≥ 5 liters/min oxygen to maintain saturations ≥ 94 % were randomised to either APP or control group. The APP group received a 3-h APP session three times per day for three days.

Results

Between 9 May and July 13, 2021, 89 adults were screened and 61 enrolled, 31 to awake prone position and 30 controls. There was no difference in the primary outcome, 7 (22.6 %) patients randomised to APP and 9 (30.0 %) controls required escalation of oxygen support (OR 0.68 (0.22-2.14), P = 0.51). There were no differences in any secondary outcomes, in APP did not improve oxygenation.

Interpretation

In COVID-19 patients, the use of APP did not prevent escalation of oxygen support from supplementary to invasive or non-invasive ventilation or improve patient respiratory physiology.

Trial registration

NCT04853979 (clinicaltrials.gov).

Analytical Review of Unplanned Extubation in Intensive Care Units and Recommendation on Multidisciplinary Preventive Approaches

Unplanned extubations (UE) frequently occur in critical care units. These events are precipitated by many risk factors and are associated with adverse outcomes for patients. We reviewed the current literature to examine factors related to UE and presented the analysis of 41 articles critical to the topic. Our review has identified specific risk factors that we discuss in this review, such as sedation strategies, physical restraints, endotracheal tube position, and specific nursing care aspects associated with an increased incidence of UE. We recommend interventions to reduce the risk of UE. However, we recommend that bundled rather than a single intervention is likely to yield higher success, given the heterogeneity of factors contributing to increasing the risk of UE.

Extracorporeal Versus Conventional Cardiopulmonary Resuscitation for In-Hospital Cardiac Arrest: A Propensity Score Matching Cohort Study

OBJECTIVE

Comparing the effects of extracorporeal cardiopulmonary resuscitation (ECPR) and conventional cardiopulmonary resuscitation (CCPR) on outcomes in patients with in-hospital cardiac arrest (IHCA) in China. The benefits of ECPR over CCPR in patients with IHCA remain controversial.

DESIGN

This article analyzed data from the BASeline Investigation of In-hospital Cardiac Arrest (BASIC-IHCA) study, which consecutively enrolled patients with IHCA from July 1, 2019, to December 31, 2020. Patients who received ECPR were selected as the case group and matched with patients who received CCPR as the control group by propensity score at a ratio of 1:4. A parallel questionnaire survey of participating hospitals was conducted, to collect data on ECPR cases from January 1, 2021 to November 30, 2021. The primary outcome was survival to discharge or 30-day survival.

SETTING

We included 39 hospitals across 31 provinces in China.

PATIENTS

Patients receiving cardiopulmonary resuscitation and without contraindications to ECPR were selected from the BASIC-IHCA database. Patients older than 75 years, not witnessed, or with cardiopulmonary resuscitation duration less than 10 min were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 4853 patients met the inclusion criteria before matching, with 34 undergoing ECPR (median age, 56.5 yr; 67.65% male) and 4819 underwent CCPR (median age, 59 yr; 64.52% male). There were 132 patients receiving CCPR and 33 patients receiving ECPR who were eventually matched. The ECPR group had significantly higher survival rates at discharge or 30-day survival (21.21% vs. 7.58%, p = 0.048). The ECPR group had significantly lower mortality rates (hazard ratio 0.57; 95% CI, 0.38-0.91) than the CCPR group at discharge or 30 days. Besides the BASIC-IHCA study, the volume of ECPR implementations and the survival rate of patients with ECPR (29.4% vs. 10.4%. p = 0.004) in participating hospitals significantly improved.

CONCLUSIONS

ECPR may be beneficial compared with CCPR for patient survival after IHCA and should be considered for eligible patients with IHCA.

Return to work after out of hospital cardiac arrest, insights from a prospective multicentric French cohort

RATIONALE

About 60 to 70% of out-of-hospital cardiac arrest (OHCA) survivors who worked before cardiac arrest return to work within one year but the precise conditions for this resumption of professional activity remain little known. The objective of this study was to assess components of return to work among OHCA survivors.

PATIENTS AND METHODS

We used the French national multicentric cohort AfterRosc to include OHCA survivors admitted between April 1st 2021 and March 31st 2022, discharged alive from the Intensive Care Unit (ICU), and who were less than 65 years old. A phone-call interview was performed one year after OHCA to assess return to work, level of education, former level of occupation as well as neurological recovery. Geographic and socio-economic data from the patient's residential neighborhoods were also collected. Comparisons were performed between patients who returned to work and those who did not, using non-parametric tests.

RESULTS

Of the 251 patients included in the registry, 86 were alive at ICU discharge and 31 patients that worked prior to the OHCA were included for analysis. Seventeen survivors returned to work after a median delay of 112 days [92-157] Among them, nine (53%) had required initial work adjustments. Overall, only 6 patients (19%) had returned to work ad integrum. Higher educational level, work which required higher competence-level, higher income, living in a better socio-economical neighborhood, as well as better scores on all three standardized MPAI-4 score components (abilities, adjustment and participation) were significantly associated with return to work. Participants that had not returned to work had a significant drop of income (p = 0.0025).

CONCLUSION

In this prospective study regarding French OHCA survivors, return to work is associated with better socio-economical individual and environmental status, as well as better scores on all MPAI-4 components.

[Management of Constrictive Pericarditis : A study of 43 operated cases]

Chronic constrictive pericarditis is a rare condition characterized by clinical signs of right heart failure, due to the symphysis of the two pericardial leaflets. Our study focused on a retrospective analysis of 43 CCP surgery observations collected over an 11-year period (2003-2013). The mean age of the patients was 32 years; 65% were male; exercise dyspnea (95%) was the most frequent sign. Two main etiologies were observed: tuberculosis 58% and idiopathic causes 42%. All of our patients received a subtotal pericardectomy per median sternotomy, of which 95% had no cardiopulmonary bypass.

Acute kidney injury events in patients with diabetes using sodium glucose transporter 2 inhibitors: a meta-analysis of cohort studies

AIMS

To conduct a meta-analysis of cohort studies to explore the association between acute kidney injury (AKI) and the effect of sodium glucose transporter 2 inhibitors (SGLT2 inhibitors) in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

PubMed, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were comprehensively searched for eligible studies until April 4, 2023 on the association between AKI and use of SGLT2 inhibitors in T2DM patients. Odds ratios (ORs) and their 95% confidence intervals (CIs) were pooled using the Mantel-Haenszel method.

RESULTS

A total of 10 cohort studies (20 cohorts) and 526,863 participants were included in the meta-analysis. Compared with other glucose-lowering drugs (oGLDs), SGLT2 inhibitors were associated with a decreased risk of AKI (OR = 0.50, 95% CI 0.38-0.66, I2 = 96%). Meanwhile, SGLT2 inhibitors demonstrated a significant reduction in the incidence of AKI hospitalization compared with oGLDs (OR = 0.54, 95% CI 0.43-0.68, I2 = 92.0%). The result was consistent across different subgroups, and was robust to sensitivity analysis.

CONCLUSIONS

Compared with oGLDs, SGLT2 inhibitors reduced the risk of suffering AKI and AKI hospitalization in the real-world setting. Vigilance to the occurrence of AKI should not be an obstacle to discourage clinicians from prescribing SGLT2 inhibitors.

Can admission Braden skin score predict delirium in older adults in the intensive care unit? Results from a multicenter study

AIMS AND OBJECTIVES

To investigate whether a low Braden Skin Score (BSS), reflecting an increased risk of pressure injury, could predict the risk of delirium in older patients in the intensive care unit (ICU).

BACKGROUND

Delirium, a common acute encephalopathy syndrome in older ICU patients, is associated with prolonged hospital stay, long-term cognitive impairment and increased mortality. However, few studies have explored the relationship between BSS and delirium.

DESIGN

Multicenter cohort study.

METHODS

The study included 24,123 older adults from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and 1090 older adults from the eICU Collaborative Research Database (eICU-CRD), all of whom had a record of BSS on admission to the ICU. We used structured query language to extract relevant data from the electronic health records. Delirium, the primary outcome, was primarily diagnosed by the Confusion Assessment Method for the ICU or the Intensive Care Delirium Screening Checklist. Logistic regression models were used to validate the association between BSS and outcome. A STROBE checklist was the reporting guide for this study.

RESULTS

The median age within the MIMIC-IV and eICU-CRD databases was approximately 77 and 75 years, respectively, with 11,195 (46.4%) and 524 (48.1%) being female. The median BSS at enrollment in both databases was 15 (interquartile range: 13, 17). Multivariate logistic regression showed a negative association between BSS on ICU admission and the prevalence of delirium. Similar patterns were found in the eICU-CRD database.

CONCLUSIONS

This study found a significant negative relationship between ICU admission BSS and the prevalence of delirium in older patients.

RELEVANCE TO CLINICAL PRACTICE

The BSS, which is simple and accessible, may reflect the health and frailty of older patients. It is recommended that BSS assessment be included as an essential component of delirium management strategies for older patients in the ICU.

NO PATIENT OR PUBLIC CONTRIBUTION

This is a retrospective cohort study, and no patients or the public were involved in the design and conduct of the study.

Antibiotic-associated vanishing bile duct syndrome: a real-world retrospective and pharmacovigilance database analysis

PURPOSE

Vanishing bile duct syndrome (VBDS) is a rare, but potentially fatal adverse reaction triggered by certain medications. Few real-world studies have shown association between antibiotics and VBDS. We sought to quantify the risk and evaluate the clinical features of VBDS associated with antibiotics.

METHODS

Data from 2004 to 2022 on VBDS events induced by antibiotics were retrieved from the FDA Adverse Event Reporting System (FAERS) database and disproportionality analyses were conducted. Furthermore, case reports from 2000 to 31 December 2022 on antibiotics-induced VBDS were retrieved for retrospective analysis.

RESULTS

We collected 132 VBDS reports from the FAERS database. Fluoroquinolones had the greatest proportion and highest positive signal values of VBDS. The RORs (95% CIs) for antibiotics were fluoroquinolones 23.68 (18.12-30.95), macrolides 19.37 (13.58-27.62), carbapenems 17.39 (7.77-38.96), beta-lactam 13.28 (9.69-18.20), trimethoprim/sulfamethoxazole 9.05 (5.57-14.7), and tetracycline 4.02 (1.50-10.77). Twenty-three cases from 22 studies showed evidence of VBDS, beta-lactam (52.2%) was the most frequently reported agent. The median age was 45 years, the typical initial symptoms included rash (30.4%), fatigue/asthenia (26.1%), dark urine (21.7%) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) (21.7%). The median time to onset of VBDS was 2 weeks. All cases had abnormal liver function test, and the median level of total bilirubin was 23.6 mg/dl (range 3.2-80 mg/dl). Cessation of culprit drugs and treatment with ursodeoxycholic acid (83.3%) were not associated with improved outcomes (57.1%).

CONCLUSION

This study identified thirteen antibacterial agents with significant reporting associations with VBDS. Fluoroquinolones may be a neglected agent of inducing VBDS.

The Effect of Extracorporeal Membrane Oxygenation in Patients With Multiple Orthopaedic Injuries

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) plays a vital role in providing life support for patients with reversible cardiac or respiratory failure. Given the high rate of complications and difficulties associated with caring for ECMO patients, the goal of this study was to compare outcomes of orthopaedic surgery in polytrauma patients who received ECMO with similar patients who have not. This will help elucidate the timing and type of fixation that should be considered in patients on ECMO.

METHODS

A retrospective cohort was collected from the electronic medical record of two level I trauma centers over an 8-year period (2015 to 2022) using Current Procedural Terminology codes. Patients were matched with a similar counterpart not requiring ECMO based on sex, age, American Society of Anesthesiologists score, body mass index, injury severity score, and fracture characteristics. Outcomes measured included length of stay, number of revisions, time to definitive fixation, infection, amputation, revision surgery to promote bone healing, implant failure, bleeding requiring return to the operating room, and mortality.

RESULTS

Thirty-two patients comprised our ECMO cohort with a patient-matched control group. The ECMO cohort had an increased length of stay (40 versus 17.5 days, P = 0.001), number of amputations (7 versus 0, P = 0.011), and mortality rate (19% versus 0%, P = 0.024). When comparing patients placed on ECMO before definitive fixation and after definitive fixation, the group placed on ECMO before definitive fixation had significantly longer time to definitive fixation than the group placed on ECMO after fixation (14 versus 2.0 days, P < 0.001).

CONCLUSION

ECMO is a lifesaving measure for trauma patients with cardiopulmonary issues but can complicate fracture care. Although it is not associated with an increase in revision surgery rates, ECMO was associated with prolonged hospital stay and delays in definitive fracture surgery when initiated before definitive fixation.

LEVEL OF EVIDENCE

III.

Clinical Outcomes With Extracorporeal Membrane Oxygenation for Interstitial Lung Disease: Systematic Review and Meta-Analysis

The evidence on indications, outcomes, and complications with the use of extracorporeal membrane oxygenation (ECMO) in the setting of interstitial lung disease (ILD) is limited in the existing literature. We performed a systematic review and meta-analysis for the use of ECMO in the setting of ILD to study the prognostic factors associated with in-hospital mortality. Eighteen unique studies with a total of 1,356 patients on ECMO for ILD were identified out of which 76.5% were on ECMO as a bridge to transplant (BTT) and the rest as a bridge to recovery (BTR). The overall in-hospital mortality was 45.76%, with 71.3% and 37.8% for BTR and BTT, respectively. Among the various prognostic factors, mortality was lower with younger age (mean difference = 3.15, 95% confidence interval [CI] = 0.82-5.49), use of awake veno-arterial (VA)-ECMO compared to veno-venous (VV)-ECMO (unadjusted odds ratio [OR] = 0.22, 95% CI = 0.13-0.37) in the overall cohort. In the setting of BTT, the use of VA-ECMO had a decreased hazard ratio (HR) compared to VV-ECMO (adjusted HR = 0.34, 95% CI = 0.15-0.81, p = 0.015). The findings of our meta-analysis are critical but are derived from retrospective studies with small sample sizes and thus are of low to very low-GRADE certainty.

What is the weakest point of a secured aortic cannula in central extracorporeal membrane oxygenation?

PURPOSE

The purpose of this study was to compare techniques for securing the aortic extracorporeal membrane oxygenation (ECMO) cannula, using in vitro models.

METHODS

Two models were studied: a tissue model using porcine aortas and a stand model replacing the aorta with a metal stand to study the system independent of the tissue. Interventions in each model were divided into three experimental groups: Group 1 (3-0 Prolene® + 20-French Medtronic Arterial Cannula EOPA™), Group 2 (4-0 Prolene® + 16-French Medtronic Arterial Cannula DLP Pediatric), and Group 3 (5-0 Prolene® + 8-French Medtronic Arterial Cannula DLP Pediatric). In separate experiments, both gradual and rapid forces were applied to the cannulas, starting with 9.8 Newtons and increasing exponentially if the cannula remained secured. Additionally, the method of securing the tourniquet and the number of ties securing the tourniquet to the cannula were evaluated.

RESULTS

In the tissue model, even with a minimum force of 9.8 Newtons, the suture pulled through the aortic tissue, leaving sutures and ties intact. In the stand model, two purse-string sutures secured by two ligaclips held the cannula reliably and withstood higher total force. Dislodgement was prevented at forces close to 60 Newtons with only two hemostatic clips included in cannulation.

CONCLUSIONS

The weakest part of the aortic ECMO cannulation system using in vitro experiments was the tissue. Assuming that these experiments translate in vivo, it is therefore critical to prevent any pull on the cannulas by securing ECMO cannulas and ECMO tubing to both the patient and the patient's bed. Sutures with a larger diameter withstand more force. Two medium hemostatic clips can secure Prolene® sutures within snares as safely as a mosquito hemostat. Two polypropylene purse-string sutures secured by two hemostatic clips were most reliable at greater forces. The rationale for publishing our experiments in this manuscript is to (1) communicate our quantification of possible contributing factors to this rare and likely catastrophic complication of unintended decannulation, (2) increase awareness about this potential complication, and (3) increase vigilance to assure prevention of this dreaded complication.

Development and validation of a nomogram for oral mucosal membrane pressure injuries in ICU patients: A prospective cohort study

AIMS

Establishing a nomogram to estimate the probability of oral mucosal membrane pressure injury of endotracheal tube-intubated hospitalized patients in intensive care unit.

DESIGN

Multicentre prospective cohort study.

METHODS

Using Lasso regression and COX regression, variable selection was performed on demographic, clinical and laboratory data of 1037 ICU endotracheal tube-intubated hospitalized patients from West China Hospital, to construct a nomogram. External validation was conducted on 484 ICU endotracheal tube-intubated patients from People's Hospital of Zhongjiang County.

RESULTS

Among 38 potential predictors, five variables emerged as independent predictors, integrated into the nomogram: administration of antibiotics, nutritional therapy duration, agitation, hypotension and albumin levels.

CONCLUSIONS

We established a nomogram based on the hospital characteristics of ICU endotracheal tube-intubated patients, aiding in the prediction of the occurrence of oral mucosal membrane pressure injury.

REPORTING METHOD

The study followed TRIPOD guidelines.

RELEVANCE TO CLINICAL PRACTICE

The nomogram we developed can assist clinical worker in better identifying at-risk patients and risk factors. It enables the implementation of evidence-based nursing interventions in care to prevent the development of oral mucosal membrane pressure injury.

TRIAL REGISTRATION

The study has been registered with the Chinese Clinical Trial Registry (http://www.chictr.org.cn) under registration number ChiCTR2200056615.

Assessing Right Ventricle Over Time in Patients on Veno-Venous Extracorporeal Membrane Oxygenation: Insights From Serial Echocardiography

Extracorporeal membrane oxygenation (ECMO) is often used in acute respiratory distress syndrome (ARDS) with refractory hypoxemia. There is limited literature highlighting the development of right ventricular (RV) failure while on ECMO. We conducted a retrospective multicenter observational study including 70 patients who were placed on veno-venous (VV)-ECMO for respiratory failure at Mayo Clinic, Jacksonville, and Mayo Clinic, Rochester, between January 2018 and June 2022 and had at least two post-ECMO transthoracic echoes. The primary outcomes were the incidence and progression of RV dysfunction and dilatation. The secondary outcome was in-patient mortality. Among 70 patients in our cohort, 60.6% had a normal RV function at the time of ECMO placement, whereas only 42% had a normal RV function at the second post-ECMO echo. On multinomial regression, a moderate decrease in RV function was associated with ECMO flow (odds ratio [OR] = 2.32, p = 0.001) and ECMO duration (OR = 1.01, p = 0.01). A moderately dilated RV size was also associated with ECMO flow (OR = 2.62, p < 0.001) and ECMO duration (OR = 1.02, p = 0.02). An increasing degree of RV dysfunction was associated with worse outcomes. Our study showed that the increasing duration and flow of VV-ECMO correlated with progressive RV dilatation and dysfunction, which were associated with poor survival.

Outcomes following additional drainage during veno-venous extracorporeal membrane oxygenation: A single-center retrospective study

Refractory hypoxemia during veno-venous (V-V) extracorporeal membrane oxygenation (ECMO) may require an additional cannula (VV-V ECMO) to improve oxygenation. This intervention includes risk of recirculation and other various adverse events (AEs) such as injury to the lung, cannula malpositioning, bleeding, circuit or cannula thrombosis requiring intervention (i.e., clot), or cerebral injury. During the study period, 23 of 142 V-V ECMO patients were converted to VV-V utilizing two separate cannulas for bi-caval drainage with an additional upper extremity cannula placed for return. Of those, 21 had COVID-19. In the first 24 h after conversion, ECMO flow rates were higher (5.96 vs 5.24 L/min, p = .002) with no significant change in pump speed (3764 vs 3630 revolutions per minute [RPMs], p = .42). Arterial oxygenation (PaO2) increased (87 vs 64 mmHg, p < .0001) with comparable pre-oxygenator venous saturation (61 vs 53.3, p = .12). By day 5, flows were similar to pre-conversion values at lower pump speed but with improved PaO2. Unadjusted survival was similar in those converted to VV-V ECMO compared to V-V ECMO alone (70% [16/23] vs 66.4% [79/119], p = .77). In a mixed effect regression model, any incidence of AEs, demonstrated a negative impact on PaO2 in the first 48 h but not at day 5. VV-V ECMO improved oxygenation with increasing flows without a significant difference in AEs or pump speed. AEs transiently impacted oxygenation. VV-V ECMO is effective and feasible strategy for refractory hypoxemia on VV-ECMO allowing for higher flow rate and unchanged pump speed.

Predictors associated with successful weaning of veno-venous extracorporeal membrane oxygenation and mortality in adult patients with severe acute lung failure: Protocol of a pooled data analysis of cohort studies

BACKGROUND

Severe acute lung failure (ALF) often necessitates veno-venous extracorporeal membrane oxygenation (VV-ECMO), where identifying predictors of weaning success and mortality remains crucial yet challenging. The study aims to identify predictors of weaning success and mortality in adults undergoing VV-ECMO for severe ALF, a gap in current clinical knowledge.

METHODS AND ANALYSIS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials will be searched for cohort studies examining the predictive factors of successful weaning and mortality in adult patients on VV-ECMO due to severe ALF. Risk of bias assessment will be conducted using the Newcastle-Ottawa scale for each included study. The primary outcomes will be successful weaning from VV-ECMO and all-cause mortality. Between-study heterogeneity will be evaluated using the I2 statistic. Sensitivity, subgroup, and meta-regression analyses will be performed to ascertain potential sources of heterogeneity and assess the robustness of our results. We will use the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) tool to recommend the level of evidence.

DISCUSSION

This study seeks to provide clinically significant insights into predictors for weaning and mortality during VV-ECMO treatment for ALF, aiming to support clinical decisions and potentially influence health policy, thereby improving patient outcomes.

ETHICS AND DISSEMINATION

Given the absence of direct engagement with human subjects or access to personal medical records, ethical approval for this study is deemed unnecessary. The study findings will be shared at a scientific conference either at the global or national level. Alternatively, the results will be presented for publication in a rigorously peer-reviewed journal regarding critical care medicine.

Interpretable machine learning model for early prediction of delirium in elderly patients following intensive care unit admission: a derivation and validation study

Background and objective

Delirium is the most common neuropsychological complication among older adults admitted to the intensive care unit (ICU) and is often associated with a poor prognosis. This study aimed to construct and validate an interpretable machine learning (ML) for early delirium prediction in older ICU patients.

Methods

This was a retrospective observational cohort study and patient data were extracted from the Medical Information Mart for Intensive Care-IV database. Feature variables associated with delirium, including predisposing factors, disease-related factors, and iatrogenic and environmental factors, were selected using least absolute shrinkage and selection operator regression, and prediction models were built using logistic regression, decision trees, support vector machines, extreme gradient boosting (XGBoost), k-nearest neighbors and naive Bayes methods. Multiple metrics were used for evaluation of performance of the models, including the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, recall, F1 score, calibration plot, and decision curve analysis. SHapley Additive exPlanations (SHAP) were used to improve the interpretability of the final model.

Results

Nine thousand seven hundred forty-eight adults aged 65 years or older were included for analysis. Twenty-six features were selected to construct ML prediction models. Among the models compared, the XGBoost model demonstrated the best performance including the highest AUC (0.836), accuracy (0.765), sensitivity (0.713), recall (0.713), and F1 score (0.725) in the training set. It also exhibited excellent discrimination with AUC of 0.810, good calibration, and had the highest net benefit in the validation cohort. The SHAP summary analysis showed that Glasgow Coma Scale, mechanical ventilation, and sedation were the top three risk features for outcome prediction. The SHAP dependency plot and SHAP force analysis interpreted the model at both the factor level and individual level, respectively.

Conclusion

ML is a reliable tool for predicting the risk of critical delirium in elderly patients. By combining XGBoost and SHAP, it can provide clear explanations for personalized risk prediction and more intuitive understanding of the effect of key features in the model. The establishment of such a model would facilitate the early risk assessment and prompt intervention for delirium.

Development of clinical tools to estimate the breathing effort during high-flow oxygen therapy: A multicenter cohort study

INTRODUCTION AND OBJECTIVES

Quantifying breathing effort in non-intubated patients is important but difficult. We aimed to develop two models to estimate it in patients treated with high-flow oxygen therapy.

PATIENTS AND METHODS

We analyzed the data of 260 patients from previous studies who received high-flow oxygen therapy. Their breathing effort was measured as the maximal deflection of esophageal pressure (ΔPes). We developed a multivariable linear regression model to estimate ΔPes (in cmH2O) and a multivariable logistic regression model to predict the risk of ΔPes being >10 cmH2O. Candidate predictors included age, sex, diagnosis of the coronavirus disease 2019 (COVID-19), respiratory rate, heart rate, mean arterial pressure, the results of arterial blood gas analysis, including base excess concentration (BEa) and the ratio of arterial tension to the inspiratory fraction of oxygen (PaO2:FiO2), and the product term between COVID-19 and PaO2:FiO2.

RESULTS

We found that ΔPes can be estimated from the presence or absence of COVID-19, BEa, respiratory rate, PaO2:FiO2, and the product term between COVID-19 and PaO2:FiO2. The adjusted R2 was 0.39. The risk of ΔPes being >10 cmH2O can be predicted from BEa, respiratory rate, and PaO2:FiO2. The area under the receiver operating characteristic curve was 0.79 (0.73-0.85). We called these two models BREF, where BREF stands for BReathing EFfort and the three common predictors: BEa (B), respiratory rate (RE), and PaO2:FiO2 (F).

CONCLUSIONS

We developed two models to estimate the breathing effort of patients on high-flow oxygen therapy. Our initial findings are promising and suggest that these models merit further evaluation.

External Validation of the PREdiction of Survival on Extracorporeal Membrane Oxygenation Therapy (PRESET) Score: A Single Center Cohort Experience

Acute respiratory distress syndrome (ARDS) is a life-threatening condition affecting >10% of intensive care unit (ICU) patients worldwide with a mortality of up to 59% depending on severity. Extracorporeal membrane oxygenation (ECMO) is a potentially life-saving procedure in severe ARDS but is technically and financially challenging. In recent years, various scoring systems have been proposed to select patients most likely to benefit from ECMO, with the PREdiction of Survival on ECMO Therapy (PRESET) score being one of the most used. We collected data from 283 patients with ARDS of various etiology who underwent veno-venous (V-V) ECMO therapy at a German tertiary care ICU from January 2012 to December 2022. Median age in the cohort was 56 years, and 64.31% were males. The in-hospital mortality rate was 50.88% (n = 144). The median (25%; 75% quartile) severity scores were 38 (31; 49) for Simplified Acute Physiology Score (SAPS) II, 12 (10; 13) for Sequential Organ Failure Assessment (SOFA) and 7 (5; 8) for PRESET. Simplified Acute Physiology Score-II displayed the best prognostic value (area under the receiver operating characteristic [AUROC]: 0.665 [confidence interval (CI): 0.574-0.756; p = 0.046]). Prediction performance was weak in all analyzed scores despite good calibration. Simplified Acute Physiology Score-II had the best discrimination after adjustment of our original cohort. The use of scores explored in this study for patient selection for eligibility for V-V ECMO is not recommendable.

Indications and Outcomes for Adult Extracorporeal Membrane Oxygenation at a Military Referral Facility

INTRODUCTION

Extracorporeal life support, including extracorporeal membrane oxygenation (ECMO), is a potentially life-saving adjunct to therapy in patients experiencing pulmonary and/or cardiac failure. The U.S. DoD has only one ECMO center, in San Antonio, Texas. In this study, we aimed to analyze outcomes at this center in order to determine whether they are on par with those reported elsewhere in the literature.

MATERIALS AND METHODS

In this observational study, we analyzed data from patients treated with ECMO at the only DoD ECMO center between September 2012 and April 2020. The primary outcome was survival to discharge, and secondary outcomes were discharge disposition and incidence of complications.

RESULTS

One hundred and forty-three patients were studied, with a 70.6% rate of survival to discharge. Of the patients who survived, 32.7% were discharged home; 32.7% were discharged to a rehabilitation facility; and 33.7% were transferred to another hospital, 29.4% of whom were transferred to lung transplant centers. One patient left against medical advice. Incidence of ECMO-related complications were as follows: 64 patients (44.7%) experienced hemorrhagic complications, 80 (55.9%) had renal complications, 61 (42.6%) experienced cardiac complications, 39 (27.3%) had pulmonary complications, and 5 patients (3.5%) experienced limb ischemia. We found that these outcomes were comparable to those reported in the literature.

CONCLUSIONS

Extracorporeal membrane oxygenation can be an efficacious adjunct in management of critically ill patients who require pulmonary and/or cardiac support. This single-center observational study demonstrated that the DoD's only ECMO center has outcomes comparable with the reported data in Extracorporeal Life Support Organization's registry.

Web-based Dashboard on ECMO Utilization in Germany: An Interactive Visualization, Analyses, and Prediction Based on Real-life Data

In Germany, a comprehensive reimbursement policy for extracorporeal membrane oxygenation (ECMO) results in the highest per capita use worldwide, although benefits remain controversial. Public ECMO data is unstructured and poorly accessible to healthcare professionals, researchers, and policymakers. In addition, there are no uniform policies for ECMO allocation which confronts medical personnel with ethical considerations during health crises such as respiratory virus outbreaks.Retrospective information on adult and pediatric ECMO support performed in German hospitals was extracted from publicly available reimbursement data and hospital quality reports and processed to create the web-based ECMO Dashboard built on Open-Source software. Patient-level and hospital-level data were merged resulting in a solid base for ECMO use analysis and ECMO demand forecasting with high spatial granularity at the level of 413 county and city districts in Germany.The ECMO Dashboard ( https://www.ecmo-dash.de/ ), an innovative visual platform, presents the retrospective utilization patterns of ECMO support in Germany. It features interactive maps, comprehensive charts, and tables, providing insights at the hospital, district, and national levels. This tool also highlights the high prevalence of ECMO support in Germany and emphasizes districts with ECMO surplus - where patients from other regions are treated, or deficit - origins from which ECMO patients are transferred to other regions. The dashboard will evolve iteratively to provide stakeholders with vital information for informed and transparent resource allocation and decision-making.Accessible public routine data could support evidence-informed, forward-looking resource management policies, which are urgently needed to increase the quality and prepare the critical care infrastructure for future pandemics.

Hemorrhage and thrombosis in COVID-19-patients supported with extracorporeal membrane oxygenation: an international study based on the COVID-19 critical care consortium

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a rescue therapy in patients with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19. While bleeding and thrombosis complicate ECMO, these events may also occur secondary to COVID-19. Data regarding bleeding and thrombotic events in COVID-19 patients on ECMO are sparse.

METHODS

Using the COVID-19 Critical Care Consortium database, we conducted a retrospective analysis on adult patients with severe COVID-19 requiring ECMO, including centers globally from 01/2020 to 06/2022, to determine the risk of ICU mortality associated with the occurrence of bleeding and clotting disorders.

RESULTS

Among 1,248 COVID-19 patients receiving ECMO support in the registry, coagulation complications were reported in 469 cases (38%), among whom 252 (54%) experienced hemorrhagic complications, 165 (35%) thrombotic complications, and 52 (11%) both. The hazard ratio (HR) for Intensive Care Unit mortality was higher in those with hemorrhagic-only complications than those with neither complication (adjusted HR = 1.60, 95% CI 1.28-1.99, p < 0.001). Death was reported in 617 of the 1248 (49.4%) with multiorgan failure (n = 257 of 617 [42%]), followed by respiratory failure (n = 130 of 617 [21%]) and septic shock [n = 55 of 617 (8.9%)] the leading causes.

CONCLUSIONS

Coagulation disorders are frequent in COVID-19 ARDS patients receiving ECMO. Bleeding events contribute substantially to mortality in this cohort. However, this risk may be lower than previously reported in single-nation studies or early case reports. Trial registration ACTRN12620000421932 ( https://covid19.cochrane.org/studies/crs-13513201 ).

Partial pressure of carbon dioxide/pH interaction and its association with mortality among patients mechanically ventilated in the emergency department

OBJECTIVES

There is currently conflicting data as to the effects of hypercapnia on clinical outcomes among mechanically ventilated patients in the emergency department (ED). These conflicting results may be explained by the degree of acidosis. We sought to test the hypothesis that hypercapnia is associated with increased in-hospital mortality and decreased ventilator-free days at lower pH, but associated with decreased in-hospital mortality and increased ventilator-free days at higher pH, among patients requiring mechanical ventilation in the emergency department (ED).

METHODS

Secondary analysis of patient level data from prior clinical trials and cohort studies that enrolled adult patients who required mechanical ventilation in the ED. Patients who had a documented blood gas while on mechanical ventilation in the ED were included in these analyses. The primary outcome was in-hospital mortality, and secondary outcome was ventilator-free days. Mixed-effects logistic, linear, and survival-time regression models were used to test if pH modified the association between partial pressure of carbon dioxide (pCO2) and outcome measures.

RESULTS

Of the 2348 subjects included, the median [interquartile range (IQR)] pCO2 was 43 (35-54) and pH was 7.31 (7.22-7.39). Overall, in-hospital mortality was 27%. We found pH modified the association between pCO2 and outcomes, with higher pCO2 associated with increased probability of in-hospital mortality when pH is below 7.00, and decreased probability of in-hospital mortality when pH is above 7.10. These results remained consistent across multiple sensitivity and subgroup analyses. A similar relationship was found with ventilator-free days.

CONCLUSIONS

Higher pCO2 is associated with decreased mortality and greater ventilator-free days when pH is >7.10; however, it is associated with increased mortality and fewer ventilator-free days when the pH is below 7.00. Targeting pCO2 based on pH in the ED may be a potential intervention target for future clinical trials to improve clinical outcomes.

Multidisciplinary Consensus on the Management of Non-Invasive Respiratory Support in the COVID-19 Patient

Acute respiratory failure due to COVID-19 pneumonia often requires a comprehensive approach that includes non-pharmacological strategies such as non-invasive support (including positive pressure modes, high flow therapy or awake proning) in addition to oxygen therapy, with the primary goal of avoiding endotracheal intubation. Clinical issues such as determining the optimal time to initiate non-invasive support, choosing the most appropriate modality (based not only on the acute clinical picture but also on comorbidities), establishing criteria for recognition of treatment failure and strategies to follow in this setting (including palliative care), or implementing de-escalation procedures when improvement occurs are of paramount importance in the ongoing management of severe COVID-19 cases. Organizational issues, such as the most appropriate setting for management and monitoring of the severe COVID-19 patient or protective measures to prevent virus spread to healthcare workers in the presence of aerosol-generating procedures, should also be considered. While many early clinical guidelines during the pandemic were based on previous experience with acute respiratory distress syndrome, the landscape has evolved since then. Today, we have a wealth of high-quality studies that support evidence-based recommendations to address these complex issues. This document, the result of a collaborative effort between four leading scientific societies (SEDAR, SEMES, SEMICYUC, SEPAR), draws on the experience of 25 experts in the field to synthesize knowledge to address pertinent clinical questions and refine the approach to patient care in the face of the challenges posed by severe COVID-19 infection.

Effect of decreasing PEEP on hyperinflation and collapse in COVID-19: A computed tomography study

BACKGROUND

High positive end-expiratory pressure (PEEP>10 cmH2O) is commonly used in mechanically ventilated hypoxemic patients with COVID-19. However, some epidemiological and physiological studies indirectly suggest that using a lower PEEP may primarily and beneficially decrease lung hyperinflation in this population. Herein we directly quantified the effect of decreasing PEEP from 15 to 10 cmH2O on lung hyperinflation and collapse in mechanically ventilated patients with COVID-19.

METHODS

Twenty mechanically ventilated patients with COVID-19 underwent a lung computed tomography (CT) at PEEP of 15 and 10 cmH2O. The effect of decreasing PEEP on lung hyperinflation and collapse was directly quantified as the change in the over-aerated (density below -900 HU) and non-aerated (density above -100 HU) lung volumes. The net response to decreasing PEEP was computed as the sum of the change in those two compartments and expressed as the change in the "pathologic" lung volume. If the pathologic lung volume decreased (i.e., hyperinflation decreased more than collapse increased) when PEEP was decreased, the net response was considered positive; otherwise, it was considered negative.

RESULTS

On average, the ratio of arterial tension to inspiratory fraction of oxygen (PaO2:FiO2) in the overall study population was 137 (119-162) mmHg. In 11 (55%) patients, the net response to decreasing PEEP was positive. Their over-aerated lung volume decreased by 159 (98-186) mL, while the non-aerated lung volume increased by only 58 (31-91) mL. In nine (45%) patients, the net response was negative. Their over-aerated lung volume decreased by 46 (18-72) mL, but their non-aerated lung volume increased by 107 (44-121) mL.

CONCLUSION

In 20 patients with COVID-19 the net response to decreasing PEEP, as assessed with lung CT, was variable. In approximately half of them it was positive (and possibly beneficial), with a decrease in hyperinflation larger than the increase in collapse.

Calcium Channel Blocker Overdose: What Role Does Extracorporeal Membrane Oxygenation Have in Support? A Systematic Review of the Literature

Extracorporeal membrane oxygenation (ECMO) has had increasing prevalence and indications in the last decade. Calcium channel blocker overdose (CCBOD) can lead to significant cardiopulmonary dysfunction and has also increased in recent years. CCBOD results in cardiac depression, vasoplegia, and hyperglycemia. Expert consensus recommends treatment with calcium, high-dose insulin, inotropes, and vasopressors. Our systematic review evaluated when to initiate ECMO in the CCBOD population and the mortality rate associated with use. Electronic literature review identified all relevant studies for CCBOD and ECMO. PRISMA guidelines for systematic review were followed. Three independent authors reviewed abstracts and full texts, and only CCB ingestion without polypharmacy was included. Two authors independently collected data, which included demographics, current medical treatments, ECMO type, and survival. From 314 abstracts, 25 papers were included with a median publication year of 2019. Twenty-six patients were included with an average age of 32.7 years and 42%/58% male/female. Average time on ECMO 4.3 days. VA and VV ECMO use were 92.3% and 7.7%, respectively, and 84.6% of patients survived to hospital discharge. Before ECMO, most patients received 4-5 medical treatments (53.8%). Our systematic review demonstrates ECMO is a newly used, yet valuable therapy for CCBOD when medical treatment fails. Survival to discharge after ECMO for CCBOD is substantially higher than standard VV or VA ECMO. Medical management is still the mainstay therapy for CCBOD, but we show that a persistently unstable patient may benefit from prompt evaluation at an ECMO center for treatment.

Prognostic of red blood cell transfusion during extracorporeal membrane oxygenation therapy on mortality: A meta-analysis

BACKGROUND

This meta-analysis aimed to explore the impact of red blood cell (RBC) transfusion on mortality during extracorporeal membrane oxygenation (ECMO). Previous studies investigated the prognostic impact of RBC transfusion during ECMO on the risk of mortality, but no meta-analysis has been published before.

METHODS

The PubMed, Embase, and the Cochrane library were systematically searched for papers published up to 13 December 2021, using the MeSH terms "ECMO", "'Erythrocytes", and "Mortality" to identify meta-analyses. Total or daily RBC transfusion during ECMO and mortality were examined.

RESULTS

The random-effect model was used. Eight studies (794 patients, including 354 dead) were included. The total volume of RBC was associated with higher mortality standardized weighted difference (SWD = -0.62, 95% CI: -1.06,-0.18, p = .006; I2 = 79.7%, Pheterogeneity = 0.001). The daily volume of RBC was associated with higher mortality (SWD = -0.77, 95% CI: -1.11,-0.42, p < .001; I2 = 65.7%, Pheterogeneity = 0.020). The total volume of RBC was associated with mortality for venovenous (VV) (SWD = -0.72, 95% CI: -1.23, -0.20, p = .006) but not venoarterial ECMO (p = .126) or when reported together (p = .089). The daily volume of RBC was associated with mortality for VV (SWD = -0.72, 95% CI: -1.18, -0.26, p = 0.002; I2 = 0.0%, Pheterogeneity = 0.642) and venoarterial (SWD = -0.95, 95% CI: -1.32, -0.57, p < .001) ECMO, but not when reported together (p = .067). The sensitivity analysis suggested the robustness of the results.

CONCLUSION

When considering the total and daily volumes of RBC transfusion during ECMO, the patients who survived received smaller total and daily volumes of RBC transfusion. This meta-analysis suggests that RBC transfusion might be associated with a higher risk of mortality during ECMO.

Extracorporeal Life Support Organization Center of Excellence recognition is associated with improved failure to rescue after cardiac arrest

OBJECTIVE

The influence of Extracorporeal Life Support Organization (ELSO) center of excellence (CoE) recognition on failure to rescue after cardiac surgery is unknown. We hypothesized that ELSO CoE would be associated with improved failure to rescue.

METHODS

Patients undergoing a Society of Thoracic Surgeons index operation in a regional collaborative (2011-2021) were included. Patients were stratified by whether or not their operation was performed at an ELSO CoE. Hierarchical logistic regression analyzed the association between ELSO CoE recognition and failure to rescue.

RESULTS

A total of 43,641 patients were included across 17 centers. In total, 807 developed cardiac arrest with 444 (55%) experiencing failure to rescue after cardiac arrest. Three centers received ELSO CoE recognition, and accounted for 4238 patients (9.71%). Before adjustment, operative mortality was equivalent between ELSO CoE and non-ELSO CoE centers (2.08% vs 2.36%; P = .25), as was the rate of any complication (34.5% vs 33.8%; P = .35) and cardiac arrest (1.49% vs 1.89%; P = .07). After adjustment, patients undergoing surgery at an ELSO CoE facility were observed to have 44% decreased odds of failure to rescue after cardiac arrest, relative to patients at non-ELSO CoE facility (odds ratio, 0.56; 95% CI, 0.316-0.993; P = .047).

CONCLUSIONS

ELSO CoE status is associated with improved failure to rescue following cardiac arrest for patients undergoing cardiac surgery. These findings highlight the important role that comprehensive quality programs serve in improving perioperative outcomes in cardiac surgery.

Pregnancy-Associated Extracorporeal Membrane Oxygenation in the United States

OBJECTIVE

 The use of extracorporeal membrane oxygenation (ECMO) therapy has increased in the adult population. Studies from the H1N1 influenza pandemic suggest that ECMO deployment in pregnancy is associated with favorable outcomes. With increasing numbers of pregnant women affected by COVID-19 (coronavirus disease 2019) and potentially requiring this life-saving therapy, we sought to compare comorbidities, costs, and outcomes between pregnancy- and nonpregnancy-associated ECMO therapy among reproductive-aged female patients.

STUDY DESIGN

 We used the 2013 to 2019 National Readmissions Database. Diagnosis and procedural coding were used to identify ECMO deployment, potential indications, comorbid conditions, and pregnancy outcomes. The primary outcome was in-hospital mortality during the patient's initial ECMO stay. Secondary outcomes included length of stay and hospital charges/costs, occurrence of thromboembolic or bleeding complications during ECMO hospitalization, and mortality and readmissions up to 330 days following ECMO stay. Univariate and multivariate regression models were used to model the associations between pregnancy status and outcomes.

RESULTS

 The sample included 324 pregnancy-associated hospitalizations and 3,805 nonpregnancy-associated hospitalizations, corresponding to national estimates of 665 and 7,653 over the study period, respectively. Pregnancy-associated ECMO had lower incidence of in-hospital death (adjusted odds ratio [aOR]: 0.56, 95% confidence interval [CI]: 0.41-0.75) and bleeding complications (aOR: 0.67, 95% CI: 0.49-0.93). Length of stay was significantly shorter (adjusted rate ratio (aRR): 0.86, 95% CI: 0.77-0.96) and total hospital costs were less (aRR: 0.83, 95% CI: 0.75-0.93). Differences in the incidence of thromboembolic events (aOR: 1.04, 95% CI: 0.78-1.38) were not statistically significant.

CONCLUSION

 Pregnancy-associated ECMO therapy had lower incidence of in-hospital death, bleeding complications, total inpatient cost, and length of stay when compared with nonpregnancy-associated ECMO therapy without increased thromboembolic complications. Pregnancy-associated ECMO therapy should be offered to eligible patients.

KEY POINTS

· Pregnancy-related ECMO use was compared with nonpregnant use.. · Outcomes were equal or favored pregnancy-related deployment.. · These data may be useful when considering ECMO use in pregnancy..

Effects of gabapentin on slow-wave sleep period in critically ill adult patients: A randomized controlled trial

Sleep deprivation is a prevalent problem in critically ill patients, which leads to delayed recovery and delirium. Slow-wave sleep (SWS) is essential to energy restoration, tissue repair, and immune system strengthening. This study aimed to investigate the effects of gabapentin on SWS in critically ill patients. We performed a prospective open-label randomized controlled study to compare SWS and the clinical outcomes of gabapentin versus a control intervention in critically ill adult patients admitted to the intensive care unit (ICU) within 24 h. The patients' characteristics and sleep-related outcomes were recorded. The sleep-related outcomes, namely, bispectral analysis (BIS), the Richards-Campbell Sleep Questionnaire (RCSQ), and insulin-like growth factor-1 (IGF-1) levels, were evaluated. Furthermore, clinical outcomes and safety were assessed. Sixty patients from 348 cases were eligible for randomization. On day 3 of the study, patients in the gabapentin group had significantly increased SWS (66.79 vs. 0.00 min; p < 0.001), total sleep time (TST) (331.39 vs. 46.16 min; p = 0.001), RCSQ score (55.05 ± 20.18 vs. 32.80 ± 15.31; p < 0.001), and IGF-1 concentrations (84.33 ± 12.40 vs. 44.00 ± 10.20 ng/mL, p < 0.001) compared with the control group. Improvements in clinical outcomes, such as delirium, ICU-free days, and mechanical ventilator-free days, were observed; however, these differences did not reach statistically significant. Gabapentin at bedtime increased SWS, TST, and IGF-1 concentrations in critically ill patients. This regimen might be beneficial to critically ill patients for improving their sleep quality.

Morbid obesity's impact on COVID-19 patients requiring venovenous extracorporeal membrane oxygenation: The covid-19 critical care consortium database review

Introduction: Obesity is associated with a worse prognosis in COVID-19 patients with acute respiratory distress syndrome (ARDS). Veno-venous (V-V) Extracorporeal Membrane Oxygenation (ECMO) can be a rescue option, however, the direct impact of morbid obesity in this select group of patients remains unclear.Methods: This is an observational study of critically ill adults with COVID-19 and ARDS supported by V-V ECMO. Data are from 82 institutions participating in the COVID-19 Critical Care Consortium international registry. Patients were admitted between 12 January 2020 to 27 April 2021. They were stratified based on Body Mass Index (BMI) at 40 kg/m2. The endpoint was survival to hospital discharge.Results: Complete data available on 354 of 401 patients supported on V-V ECMO. The characteristics of the high BMI (>40 kg/m2) and lower BMI (≤40 kg/m2) groups were statistically similar. However, the 'high BMI' group were comparatively younger and had a lower APACHE II score. Using survival analysis, older age (Hazard Ratio, HR 1.49 per-10-years, CI 1.25-1.79) and higher BMI (HR 1.15 per-5 kg/m2 increase, CI 1.03-1.28) were associated with a decreased patient survival. A safe BMI threshold above which V-V ECMO would be prohibitive was not apparent and instead, the risk of an adverse outcome increased linearly with BMI.Conclusion: In COVID-19 patients with severe ARDS who require V-V ECMO, there is an increased risk of death associated with age and BMI. The risk is linear and there is no BMI threshold beyond which the risk for death greatly increases.

Epidemiology of Intensive Care Patients Classified as a Third Sex in Australia and New Zealand

BACKGROUND

Patient sex affects treatment and outcomes in critical illness. Previous studies of sex differences in critical illness compared female and male patients. In this study, we describe the group of patients classified as a third sex admitted to ICUs in Australia and New Zealand.

RESEARCH QUESTION

What are the admission characteristics and outcomes of ICU patients classified as belonging to a third sex group compared with patients classified as female or male?

STUDY DESIGN AND METHODS

Retrospective observational study of admissions to 200 ICUs, recorded in the Australian and New Zealand Intensive Care Society's Adult Patient Database from 2018 to 2022. We undertook mixed effect logistic regression to compare hospital mortality across the sex groups, adjusted for illness severity, diagnosis, treatment limitation, year, and hospital.

RESULTS

We examined 892,161 admissions, of whom 525 (0.06%) were classified as third sex. Patients classified as third sex were represented across all diagnostic categories, jurisdictions, and hospital types. On average, they were younger than the groups classified as female (59.2 ± 20.0 vs 61.3 ± 18.4 years; P = .02) or male (63.2 ± 16.7 years; P < .001), respectively. Patients classified as third sex were more likely to be admitted after orthopedic surgery (10.1% third sex admissions [95% CI, 7.7%-13.0%]; 6.2% female [95% CI, 6.1%-6.3%]; 4.8% male [95% CI, 4.7%-4.9%]) and drug overdose (8.8% third sex admissions [95% CI, 6.5%-11.5%]; 4.2% female [95% CI, 4.1%-4.2%]; 3.1% male [95% CI, 3.0%-3.1%]). There was no difference in the adjusted hospital mortality of patients classified as third sex compared with the other groups.

INTERPRETATION

Patients classified as third sex composed a small minority group of adult ICU patients. This group had a different diagnostic case mix but similar outcomes to the groups classified as female or male. Further characterizing a third sex group will require improved processes for recording sex and gender in health records.

Venopulmonary Artery Extracorporeal Life Support (VPa ECMO): A Novel Strategy for Refractory Hypoxemia Complicating VV ECMO

Refractory hypoxemia (RH) during venovenous extracorporeal membrane oxygenation (VV ECMO) support is a complex problem that limits the benefit of this therapy. The need for sustained deep sedation and delays in active rehabilitation are considered as a direct consequence of RH. Changing from VV ECMO to a configuration that returns the flow to pulmonary artery, such as venopulmonary extracorporeal membrane oxygenation (VPa ECMO) may decrease recirculation and improve systemic oxygen delivery. We present a retrospective report that describes the impact of VPa ECMO on oxygenation during sedation withdrawal in 41 patients who received VV ECMO for coronavirus disease 2019 (COVID-19). We evidenced that arterial oxygen pressure (PaO 2 ) increased from 68 to 112.3 mm Hg ( p = 0.001) with a reduction of ECMO flow (5.7-4.8 L/m; p = 0.001). Other findings included lower rates of depth sedation (Richmond Agitation Sedation Scale [RASS] ≤3, 37-63%; p = 0.007) and lower requirement inotropic support assessed by LVIS score (4.7-1.1; p = 0.005). Discharge survival was 54% with a sustained benefit until day 79. This cannulation strategy improved effectively PaO 2 in this cohort, it may be an alternative in patients with RH in VV ECMO.

Efficacy of a Single Day Extracorporeal Membrane Oxygenation Training Course for Critical Care Air Transport Team Eligible Personnel

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is an advanced medical technology that is used to treat respiratory and heart failure. The U.S. military has used ECMO in the care of combat casualties during Operation Enduring Freedom and Operation Iraqi Freedom as well as in the treatment of patients during the recent Coronavirus Disease 2019 pandemic. However, few Military Health System personnel have training and experience in the use of ECMO therapy. To address this dearth of expertise, we developed and evaluated an accelerated ECMO course for military medical personnel.

OBJECTIVES

To compare the efficacy of an accelerated ECMO course for Military Health System critical care teams.

METHODS

Seventeen teams, each consisting of a physician and nurse, underwent a 5-h accelerated ECMO course. Similar to our previous live-tissue ECMO training program (phases I and II), each team watched prerecorded ECMO training lectures. Subjects then practiced priming the ECMO circuit, cannulating ECMO, initiating ECMO, and correcting common complications on an ECMO simulation model. An added component to this phase III project included transportation and telemedicine consultation availability. Training success was evaluated via knowledge and confidence assessments, and observation of each team attempting to initiate ECMO on a Yorkshire swine patient model, transport the patient model, and troubleshoot complications with the support of telemedicine consultation when desired.

RESULTS

Seventeen teams successfully completed the course. All seventeen teams (100%) successfully placed the swine on veno-arterial ECMO. Of those, 15 teams successfully transitioned to veno-arterial-venous ECMO. The knowledge assessments of physicians and nurses increased by 12.2% from pretest (mean of 62.1%, SD 10.4%) to posttest (mean of 74.4%, SD 8.2%), P < .0001; their confidence assessments increased by 41.1% from pretest (mean of 20.1%, SD 11.8%) to posttest (mean of 61.2%, SD 18.6%).

CONCLUSIONS

An abbreviated 1-day lecture and hands-on task-trainer-based ECMO course resulted in a high rate of successful skill demonstration and improvement of physicians' and nurses' knowledge assessments and confidence levels, similar to our previous live-tissue training program. When compared to our previous studies, the addition of telemedicine and patient transportation to this study did not affect the duration or performance of procedures.

Association of stress hyperglycemia ratio and mortality in patients with sepsis: results from 13,199 patients

BACKGROUND

The stress hyperglycemia ratio (SHR), adjusted for average glycemic status, is suggested for assessing actual blood glucose levels. Its link with adverse outcomes is known in certain populations, yet its impact on sepsis patients' prognosis is unclear. This study explores the association between SHR and mortality in sepsis.

METHODS

We included 13,199 sepsis patients in this study and categorized SHR into distinct groups. Additionally, we utilized restricted cubic spline analysis to evaluate the correlation between SHR as a continuous variable and mortality. The primary outcome was 1-year all-cause mortality. Logistic regression and Cox proportional hazards models were employed to assess the associations between the SHR and both in-hospital mortality and 1-year mortality, respectively.

RESULTS

Among the study participants, 4,690 (35.5%) patients died during the 1-year follow-up. After adjusting for confounding variables, we identified a U-shaped correlation between SHR and 1-year mortality. Using an SHR of 0.99 as the reference point, the hazard ratio for predicted 1-year mortality increased by 1.17 (95% CI 1.08 to 1.27) per standard deviation above 0.99, whereas each standard deviation increase predicted the hazard ratio of 0.52 (95% CI 0.39 to 0.69) below 0.99. Furthermore, we found that SHR could enhance the predictive performance of conventional severity scores.

CONCLUSION

There exists a U shaped association between SHR and mortality in sepsis patients, where both low and high SHR values are associated with an increased risk of poor outcomes.

Advanced Respiratory Monitoring during Extracorporeal Membrane Oxygenation

Advanced respiratory monitoring encompasses a diverse range of mini- or noninvasive tools used to evaluate various aspects of respiratory function in patients experiencing acute respiratory failure, including those requiring extracorporeal membrane oxygenation (ECMO) support. Among these techniques, key modalities include esophageal pressure measurement (including derived pressures), lung and respiratory muscle ultrasounds, electrical impedance tomography, the monitoring of diaphragm electrical activity, and assessment of flow index. These tools play a critical role in assessing essential parameters such as lung recruitment and overdistention, lung aeration and morphology, ventilation/perfusion distribution, inspiratory effort, respiratory drive, respiratory muscle contraction, and patient-ventilator synchrony. In contrast to conventional methods, advanced respiratory monitoring offers a deeper understanding of pathological changes in lung aeration caused by underlying diseases. Moreover, it allows for meticulous tracking of responses to therapeutic interventions, aiding in the development of personalized respiratory support strategies aimed at preserving lung function and respiratory muscle integrity. The integration of advanced respiratory monitoring represents a significant advancement in the clinical management of acute respiratory failure. It serves as a cornerstone in scenarios where treatment strategies rely on tailored approaches, empowering clinicians to make informed decisions about intervention selection and adjustment. By enabling real-time assessment and modification of respiratory support, advanced monitoring not only optimizes care for patients with acute respiratory distress syndrome but also contributes to improved outcomes and enhanced patient safety.

Acute Lung Injury after Cardiopulmonary Resuscitation: A Narrative Review

Although cardiopulmonary resuscitation (CPR) includes lifesaving maneuvers, it might be associated with a wide spectrum of iatrogenic injuries. Among these, acute lung injury (ALI) is frequent and yields significant challenges to post-cardiac arrest recovery. Understanding the relationship between CPR and ALI is determinant for refining resuscitation techniques and improving patient outcomes. This review aims to analyze the existing literature on ALI following CPR, emphasizing prevalence, clinical implications, and contributing factors. The review seeks to elucidate the pathogenesis of ALI in the context of CPR, assess the efficacy of CPR techniques and ventilation strategies, and explore their impact on post-cardiac arrest outcomes. CPR-related injuries, ranging from skeletal fractures to severe internal organ damage, underscore the complexity of managing post-cardiac arrest patients. Chest compression, particularly when prolonged and vigorous, i.e., mechanical compression, appears to be a crucial factor contributing to ALI, with the concept of cardiopulmonary resuscitation-associated lung edema (CRALE) gaining prominence. Ventilation strategies during CPR and post-cardiac arrest syndrome also play pivotal roles in ALI development. The recognition of CPR-related lung injuries, especially CRALE and ALI, highlights the need for research on optimizing CPR techniques and tailoring ventilation strategies during and after resuscitation.

Extracorporeal membrane oxygenation technology for adults: an evidence mapping based on systematic reviews

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a cutting-edge life-support measure for patients with severe cardiac and pulmonary illnesses. Although there are several systematic reviews (SRs) about ECMO, it remains to be seen how quality they are and how efficacy and safe the information about ECMO they describe is in these SRs. Therefore, performing an overview of available SRs concerning ECMO is crucial.

METHODS

We searched four electronic databases from inception to January 2023 to identify SRs with or without meta-analyses. The Assessment of Multiple Systematic Reviews 2 (AMSTAR-2) tool, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system were used to assess the methodological quality, and evidence quality for SRs, respectively. A bubble plot was used to visually display clinical topics, literature size, number of SRs, evidence quality, and an overall estimate of efficacy.

RESULTS

A total of 17 SRs met eligibility criteria, which were combined into 9 different clinical topics. The methodological quality of the included SRs in this mapping was "Critically low" to "Moderate". One of the SRs was high-quality evidence, three on moderate, three on low, and two on very low-quality evidence. The most prevalent study used to evaluate ECMO technology was observational or cohort study with frequently small sample sizes. ECMO has been proven beneficial for severe ARDS and ALI due to the H1N1 influenza infection. For ARDS, ALF or ACLF, and cardiac arrest were concluded to be probably beneficial. For dependent ARDS, ARF, ARF due to the H1N1 influenza pandemic, and cardiac arrest of cardiac origin came to an inconclusive conclusion. There was no evidence for a harmful association between ECMO and the range of clinical topics.

CONCLUSIONS

There is limited available evidence for ECMO that large sample, multi-center, and multinational RCTs are needed. Most clinical topics are reported as beneficial or probably beneficial of SRs for ECMO. Evidence mapping is a valuable and reliable methodology to identify and present the existing evidence about therapeutic interventions.

Review article: Telehealth in Emergency Medicine in Australasia: Advantages and barriers

The COVID-19 pandemic catapulted Telehealth to the forefront of Emergency Medicine (EM) as an alternative way of assessing and managing patients. This challenged the traditional idea that EM can only be practised within brick-and-mortar EDs. Many Emergency Physicians may find the idea of practising Telehealth in Emergency Medicine (TEM) confronting, particularly in the absence of training and clear practice guidelines. The purpose of the present paper is to describe the current use of TEM in Australasia, and outline the advantages and barriers in adopting this practice domain.

Multidrug-resistant pathogens and ventilator-associated pneumonia in critically ill COVID-19 and non-COVID-19 patients: a prospective observational monocentric comparative study

BACKGROUND

The COVID-19 pandemic has increased the incidence of ventilator-associated pneumonia (VAP) among critically ill patients. However, a comparison of VAP incidence in COVID-19 and non-COVID-19 cohorts, particularly in a context with a high prevalence of multidrug-resistant (MDR) organisms, is lacking.

MATERIAL AND METHODS

We conducted a single-center, mixed prospective and retrospective cohort study comparing COVID-19 patients admitted to the intensive care unit (ICU) of the "Città della Salute e della Scienza" University Hospital in Turin, Italy, between March 2020 and December 2021 (COVID-19 group), with a historical cohort of ICU patients admitted between June 2016 and March 2018 (NON-COVID-19 group). The primary objective was to define the incidence of VAP in both cohorts. Secondary objectives were to evaluate the microbial cause, resistance patters, risk factors and impact on 28 days, ICU and in-hospital mortality, duration of ICU stay, and duration of hospitalization).

RESULTS

We found a significantly higher incidence of VAP (51.9% - n = 125) among the 241 COVID-19 patients compared to that observed (31.2% - n = 78) among the 252 NON-COVID-19 patients. The median SOFA score was significantly lower in the COVID-19 group (9, Interquartile range, IQR: 7-11 vs. 10, IQR: 8-13, p < 0.001). The COVID-19 group had a higher prevalence of Gram-positive bacteria-related VAP (30% vs. 9%, p < 0.001), but no significant difference was observed in the prevalence of difficult-to-treat (DTR) or MDR bacteria. ICU and in-hospital mortality in the COVID-19 and NON-COVID-19 groups were 71% and 74%, vs. 33% and 43%, respectively. The presence of COVID-19 was significantly associated with an increased risk of 28-day all-cause hospital mortality (Hazard ratio, HR: 7.95, 95% Confidence Intervals, 95% CI: 3.10-20.36, p < 0.001). Tracheostomy and a shorter duration of mechanical ventilation were protective against 28-day mortality, while dialysis and a high SOFA score were associated with a higher risk of 28-day mortality.

CONCLUSION

COVID-19 patients with VAP appear to have a significantly higher ICU and in-hospital mortality risk regardless of the presence of MDR and DTR pathogens. Tracheostomy and a shorter duration of mechanical ventilation appear to be associated with better outcomes.

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

Extracorporeal life support (ECLS) serves as a rescue therapy for patients with congenital diaphragmatic hernia (CDH) and severe cardiopulmonary failure, and only half of these patients survive to discharge. This costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary support. Some contraindications to ECLS do exist such as coagulopathy, lethal chromosomal or congenital anomaly, very preterm birth, or very low birth weight, but many of these limits are being evaluated through further research. Consensus guidelines from the past decade vary in recommendations for ECLS use in patients with CDH but this therapy appears to have a survival benefit in the most severe subset of patients. Improved outcomes have been observed for patients treated at high-volume centers. This review details the evolving literature surrounding management paradigms for timing of CDH repair for patients receiving preoperative ECLS. Most recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this population. Longer ECLS runs are associated with decreased survival, and patient physiology should guide ECLS weaning and eventual decannulation rather than limiting patients to arbitrary run lengths. Standardization of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

The microbiological profile of necrotising fasciitis at a secondary level hospital in Gauteng

Background

Necrotising fasciitis (NF) is a fulminant soft tissue infection that requires timely diagnosis, urgent surgical debridement, and appropriate antimicrobial therapy. The choice of empiric antimicrobial therapy depends on the microorganisms cultured and the antimicrobial resistance profile of the institution. Necrotising fasciitis has not been studied in our setting.

Objectives

The aim of the study was to audit the microbiological profile of NF and antimicrobial susceptibility profile.

Method

This was a retrospective study in a secondary level hospital from the period of 2014-2020. The patients' demographic data, clinical features, location of infection, comorbidities, laboratory and microbiological profiles were analysed.

Results

There were 53 patients during 2014-2020 with median age of 45.5 (38.5-56.0) years. The majority of the patients were males (35 [66.04%]), had no comorbidities (25 [47.17%]), and the lower limb was the most common anatomic site (17 [32.08%]). Type II (monomicrobial) NF was the predominant type (31 [58.49%]). Staphylococcus aureus was the most prevalent Gram-positive bacteria (18 [38%]) and Escherichia coli, the main species isolated in the Gram-negative bacteria (14 [36%]) with susceptibility to cloxacillin (94%) and amoxicillin and/or clavulanic acid (92%), respectively.

Conclusion

Staphylococcus aureus and Escherichia coli were the most common bacteria with low rate of antimicrobial resistance. Amoxicillin and/or clavulanic acid and an adjunctive clindamycin are appropriate antimicrobial therapy for empiric treatment for NF in our setting.

Contribution

Amoxicillin and/or clavulanic acid and an adjunctive clindamycin can be used as an empiric treatment for NF.

Hypocapnia is associated with increased in-hospital mortality and 1 year mortality in acute heart failure patients

AIMS

Both hypercapnia and hypocapnia are common in patients with acute heart failure (AHF), but the association between partial pressure of arterial carbon dioxide (PaCO2) and AHF prognosis remains unclear. The objective of this study was to investigate the connection between PaCO2 within 24 h after admission to the intensive care unit (ICU) and mortality during hospitalization and at 1 year in AHF patients.

METHODS AND RESULTS

AHF patients were enrolled from the Medical Information Mart for Intensive Care IV database. The patients were divided into three groups by PaCO2 values of <35, 35-45, and >45 mmHg. The primary outcome was to investigate the connection between PaCO2 and in-hospital mortality and 1 year mortality in AHF patients. The secondary outcome was to assess the prediction value of PaCO2 in predicting in-hospital mortality and 1 year mortality in AHF patients. A total of 2374 patients were included in this study, including 457 patients in the PaCO2 < 35 mmHg group, 1072 patients in the PaCO2 = 35-45 mmHg group, and 845 patients in the PaCO2 > 45 mmHg group. The in-hospital mortality was 19.5%, and the 1 year mortality was 23.9% in the PaCO2 < 35 mmHg group. Multivariate logistic regression analysis showed that the PaCO2 < 35 mmHg group was associated with an increased risk of in-hospital mortality [hazard ratio (HR) 1.398, 95% confidence interval (CI) 1.039-1.882, P = 0.027] and 1 year mortality (HR 1.327, 95% CI 1.020-1.728, P = 0.035) than the PaCO2 = 35-45 mmHg group. The PaCO2 > 45 mmHg group was associated with an increased risk of in-hospital mortality (HR 1.387, 95% CI 1.050-1.832, P = 0.021); the 1 year mortality showed no significant difference (HR 1.286, 95% CI 0.995-1.662, P = 0.055) compared with the PaCO2 = 35-45 mmHg group. The Kaplan-Meier survival curves showed that the PaCO2 < 35 mmHg group had a significantly lower 1 year survival rate. The area under the receiver operating characteristic curve for predicting in-hospital mortality was 0.591 (95% CI 0.526-0.656), and the 1 year mortality was 0.566 (95% CI 0.505-0.627) in the PaCO2 < 35 mmHg group.

CONCLUSIONS

In AHF patients, hypocapnia within 24 h after admission to the ICU was associated with increased in-hospital mortality and 1 year mortality. However, the increase in 1 year mortality may be influenced by hospitalization mortality. Hypercapnia was associated with increased in-hospital mortality.