Prediction of Long-Term Physical, Mental, and Cognitive Problems Following Critical Illness: Development and External Validation of the PROSPECT Prediction Model

OBJECTIVES

ICU survivors often suffer from long-lasting physical, mental, and cognitive health problems after hospital discharge. As several interventions that treat or prevent these problems already start during ICU stay, patients at high risk should be identified early. This study aimed to develop a model for early prediction of post-ICU health problems within 48 hours after ICU admission.

DESIGN

Prospective cohort study in seven Dutch ICUs.

SETTING/PATIENTS

ICU patients older than 16 years and admitted for greater than or equal to 12 hours between July 2016 and March 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Outcomes were physical problems (fatigue or ≥ 3 new physical symptoms), mental problems (anxiety, depression, or post-traumatic stress disorder), and cognitive impairment. Patient record data and questionnaire data were collected at ICU admission, and after 3 and 12 months, of 2,476 patients. Several models predicting physical, mental, or cognitive problems and a composite score at 3 and 12 months were developed using variables collected within 48 hours after ICU admission. Based on performance and clinical feasibility, a model, PROSPECT, predicting post-ICU health problems at 3 months was chosen, including the predictors of chronic obstructive pulmonary disease, admission type, expected length of ICU stay greater than or equal to 2 days, and preadmission anxiety and fatigue. Internal validation using bootstrapping on data of the largest hospital ( n = 1,244) yielded a C -statistic of 0.73 (95% CI, 0.70-0.76). External validation was performed on data ( n = 864) from the other six hospitals with a C -statistic of 0.77 (95% CI, 0.73-0.80).

CONCLUSIONS

The developed and externally validated PROSPECT model can be used within 48 hours after ICU admission for identifying patients with an increased risk of post-ICU problems 3 months after ICU admission. Timely preventive interventions starting during ICU admission and follow-up care can prevent or mitigate post-ICU problems in these high-risk patients.

MiCare study, an evaluation of structured, multidisciplinary and personalised post-ICU care on physical and psychological functioning, and quality of life of former ICU patients: a study protocol of a stepped-wedge cluster randomised controlled trial

INTRODUCTION

Over 70% of the intensive care unit (ICU) survivors suffer from long-lasting physical, mental and cognitive problems after hospital discharge. Post-ICU care is recommended by international guidelines, but evidence for cost-effectiveness lacks. The aim of this study is to evaluate the clinical effectiveness and cost-effectiveness of structured, multidisciplinary and personalised post-ICU care versus usual care on physical and psychological functioning and health-related quality of life (HRQoL) of ICU survivors, 1- and 2-year post-ICU discharge.

METHODS AND ANALYSIS

The MONITOR-IC post-ICU care study (MiCare study) is a multicentre stepped-wedge randomised controlled trial conducted in five hospitals. Adult patients at high risk for critical illness-associated morbidity post-ICU will be selected and receive post-ICU care, including an invitation to the post-ICU clinic 3 months after ICU discharge. A personalised long-term recovery plan tailored to patients' reported outcome measures will be made. 770 (intervention) and 1480 (control) patients will be included. Outcomes are 1- and 2-year HRQoL (EuroQol Instrument (EQ-5D-5L)), physical (fatigue and new physical problems), mental (anxiety, depression and post-traumatic stress disorder), and cognitive symptoms and cost-effectiveness. Medical data will be retrieved from patient records and cost data from health insurance companies.

ETHICS AND DISSEMINATION

Due to the lack of evidence, Dutch healthcare insurers do not reimburse post-ICU care. Therefore, evaluation of cost-effectiveness and integration in guidelines supports the evidence. Participation of several societies for physicians, nurses, paramedics, and patients and relatives in the project team increases the support for implementation of the intervention in clinical practice. Patients and relatives will be informed by the patient associations, hospitals and professional associations. Informing healthcare insurers about this project's results is important for the consideration for inclusion of post-ICU care in Dutch standard health insurance. The study is approved by the Radboud University Medical Centre research ethics committee (2021-13125).

TRIAL REGISTRATION NUMBER

NCT05066984.

Development of a practically usable prediction model for quality of life of ICU survivors: A sub-analysis of the MONITOR-IC prospective cohort study

PURPOSE

As the goal of ICU treatment is survival in good health, we aimed to develop a prediction model for ICU survivors' change in quality of life (QoL) one year after ICU admission.

MATERIALS & METHODS

This is a sub-study of the prospective cohort MONITOR-IC study. Adults admitted ≥12 h to the ICU of a university hospital between July 2016-January 2019 were included. Moribund patients were excluded. Change in QoL one year after ICU admission was quantified using the EuroQol five-dimensional (EQ-5D-5L) questionnaire, and Short-Form 36 (SF-36). Multivariable linear regression analysis and best subsets regression analysis (SRA) were used. Models were internally validated by bootstrapping.

RESULTS

The PREdicting PAtients' long-term outcome for Recovery (PREPARE) model was developed (n = 1308 ICU survivors). The EQ-5D-models had better predictive performance than the SF-36-models. Explained variance (adjusted R²) of the best model (33 predictors) was 58.0%. SRA reduced the number of predictors to 5 (adjusted R² = 55.3%, SE = 0.3), including QoL, diagnosis of a Cardiovascular Incident and frailty before admission, sex, and ICU-admission following planned surgery.

CONCLUSIONS

Though more long-term data are needed to ascertain model accuracy, in future, the PREPARE model may be used to better inform and prepare patients and their families for ICU recovery.

[Autointoxication with 'suicide powder']

We present two patients who were treated for an intentional overdose of sodium nitrite. When ingested sodium nitrite leads to severe methaemoglobinaemia, resulting in severe hypoxia (as methaemoglobin does not transport oxygen), vasodilation and hypotension. Symptoms include cyanosis, headache, nausea, convulsions, coma and death. When measured by pulse oximetry, patients with a sodium nitrite intoxication and severe methaemoglobinaemia generally have an oxygen saturation of around 85%. This value is unreliable as the oxygen content of the blood is often extremely low - this can be confirmed by arterial blood gas analysis. Treatment of sodium nitrite intoxication consists of intravenous administration of methylthioninium chloride 1-2 mg/kg. Methylthioninium chloride converts the methaemoglobin back to haemoglobin. Due to the pharmacokinetics of methylthioninium chloride and sodium nitrite, a rebound effect is not to be expected. The only contra-indication for methylthioninium chloride is glucose-6-phosphate dehydrogenase deficiency, which is extremely rare in the Netherlands.

On-line blood viscosity monitoring in vivo with a central venous catheter, using electrical impedance technique

Blood viscosity is an important determinant of microvascular hemodynamics and also reflects systemic inflammation. Viscosity of blood strongly depends on the shear rate and can be characterized by a two parameter power-law model. Other major determinants of blood viscosity are hematocrit, level of inflammatory proteins and temperature. In-vitro studies have shown that these major parameters are related to the electrical impedance of blood. A special central venous catheter was developed to measure electrical impedance of blood in-vivo in the right atrium. Considering that blood viscosity plays an important role in cerebral blood flow, we investigated the feasibility to monitor blood viscosity by electrical bioimpedance in 10 patients during the first 3 days after successful resuscitation from a cardiac arrest. The blood viscosity-shear rate relationship was obtained from arterial blood samples analyzed using a standard viscosity meter. Non-linear regression analysis resulted in the following equation to estimate in-vivo blood viscosity (Viscosity(imp)) from plasma resistance (R(p)), intracellular resistance (R(i)) and blood temperature (T) as obtained from right atrium impedance measurements: Viscosity(imp)=(-15.574+15.576R(p)T)SR ((-.138RpT-.290Ri)). This model explains 89.2% (R(2)=.892) of the blood viscosity-shear rate relationship. The explained variance was similar for the non-linear regression model estimating blood viscosity from its major determinants hematocrit and the level of fibrinogen and C-reactive protein (R(2)=.884). Bland-Altman analysis showed a bias between the in-vitro viscosity measurement and the in-vivo impedance model of .04 mPa s at a shear rate of 5.5s(-1) with limits of agreement between -1.69 mPa s and 1.78 mPa s. In conclusion, this study demonstrates the proof of principle to monitor blood viscosity continuously in the human right atrium by a dedicated central venous catheter equipped with an impedance measuring device. No safety problems occurred and there was good agreement with in-vitro measurements of blood viscosity.

Predictors of poor neurologic outcome in patients after cardiac arrest treated with hypothermia: a retrospective study

INTRODUCTION

Outcome studies in patients with anoxic-ischemic encephalopathy focus on the early and reliable prediction of an outcome no better than a vegetative state or severe disability. We determined the effect of mild therapeutic hypothermia on the validity of the currently used clinical practice parameters.

METHODS

We conducted a retrospective cohort study of adult comatose patients after cardiac arrest treated with hypothermia. All data were collected from medical charts and laboratory files and analyzed from the day of admission to the intensive care unit until day 7, discharge from the intensive care unit or death using the Utstein definitions for the registration of the data.

RESULTS

We analyzed the data of 103 patients. The combination of an M1 or M2 on the Glasgow Coma Scale or absent pupillary reactions or absent corneal reflexes on day 3 was present in 80.6% of patients with an unfavourable and 11.1% of patients with a favourable outcome. The combination of M1 or M2 and absent pupillary reactions to light and absent corneal reflexes on day 3 was present in 14.9% of patients with an unfavourable and none of the patients with a favourable outcome. None of the patients with a favourable outcome had a bilaterally absent somatosensory evoked potential of the median nerve. The value of electroencephalogram patterns in predicting outcome was low, except for reactivity to noxious stimuli.

CONCLUSIONS

No single clinical or electrophysiological parameter has sufficient accuracy to determine prognosis and decision making in patients after cardiac arrest, treated with hypothermia.