Do-Not-Attempt-Cardiopulmonary-Resuscitation decisions in the hospital setting

Abstract

Background: A Do-Not-Attempt-Cardiopulmonary-Resuscitation (DNACPR) order can be placed when CPR is not in accordance with the patient’s will, when CPR is considered not to benefit the patient, or when CPR is very unlikely to be successful because the patient is dying from an irreversible condition. The decision to withhold CPR involves assessment of the predictors for favourable outcome, in compound with the patient’s values and goals of care to make a decision that is of benefit to the patient. Throughout this process there are ethical directives and legislations to relate to. Previous studies have shown that it is difficult for medical personnel to accurately predict outcome after cardiac arrest, but there is no supportive prediction model established in clinical practice. There are indications of shortages in adherence to legislation regarding DNACPR orders in our setting, but clinical practice has not been evaluated on a larger scale. Further, there is scarce knowledge about the grounds for DNACPR decisions based on the clinical practice, about the use of DNACPR orders, and the characteristics of those receiving them.

Aims: The overall aim of this thesis was to facilitate and investigate the decision process for DNACPR order placement in the hospital setting and fill knowledge gaps in the epidemiology of DNACPR orders. More specifically, the aim was external validation of the pre-arrest prediction model the Good Outcome Following Attempted Resuscitation (GOFAR) score (study I), model update of the GO-FAR score with development of a prediction model for the Swedish setting (study II), evaluation of adherence to the Swedish legislation regarding documentation of DNACPR order placement, exploration of the decision process in clinical practice (study III), and assessment of the use of DNACPR orders, characteristics and outcome for the patients (study IV).

Methods: Study I and II included adult in-hospital cardiac arrests (IHCA) in the Swedish Registry for Cardiopulmonary Resuscitation (SRCR) from 2013 to 2104 in the Stockholm region. Outcome in study I was neurologically intact survival defined as Cerebral Performance Category score (CPC) 1 and in study II outcome was favourable neurological survival defined as CPC 1–2. Outcome and patient characteristics were retrieved from SRCR, predictor variables from manual review of electronic patient records and from the National patient registry (NPR). External validation of the GO-FAR score was based on assessment of the discrimination with area under the receiver operating characteristics (AUROC) curve, calibration and risk group categorisation. Model update was based on the results in study I and included change of outcome and addition of the predictor chronic comorbidity. The study population and variables in III and IV was obtained from Karolinska University Hospital’s local administrative database and NPR and included adult admissions through the Emergency Department (ED) from 1 January to 31 October 2015. Study III included only patients with DNACPR orders issued during hospitalisation. In study III the DNACPR form in the electronic patient record was used to evaluate adherence to legislation regarding documentation of DNACPR orders and to explore aspects of the decision process in clinical practice through qualitative content analysis.

Results: Study I and II included 717 IHCA. In study I the GO-FAR score showed good discrimination with AUROC of 0.82 (95% CI 0.78–0.86), but risk group categorisation and calibration showed an underestimation of the probability of neurologically intact survival. Study II provided the updated prediction model the Prediction of outcome for In-Hospital Cardiac Arrest (PIHCA) score. The AUROC for the PIHCA score was 0.81 (95% CI 0.807– 0.810). With a cut-off of 3% likelihood of favourable neurological survival the PIHCA score could classify patients with favourable neurological outcome correctly (99% sensitivity), but for patients with poor outcome (death or CPC >2) the PIHCA score’s correct classification was limited (8% specificity). This was outweighed by a high negative predictive value (97%) for classification into low likelihood of favourable neurological survival (≤ 3%). Study III included 3,583 DNACPR forms. Mainly due to impaired cognition, it was not possible to consult with the patient 40% of cases. For these patients, a relative was consulted in 46%. For competent patients, consultation took place in 28% and the most common patient attitude was that the DNACPR order adhered with their preferences. Severe chronic comorbidity, malignancy or multimorbidity alone or in combination with acute illness was most common as grounds for DNACPR orders. All requirements in the legislation regarding documentation of DNACPR orders were fulfilled in 10%. Study IV included 25,646 adult admissions to Karolinska University Hospital of whom 11% received a DNACPR order during the hospitalisation. Patients with DNACPR orders were older, with higher burden of chronic comorbidities and more severe acute illness, hospital mortality and one-year mortality compared to those without. Characteristics of patients with DNACPR orders were similar regardless of hospital mortality, however, patients who died in-hospital presented more acutely unwell in the ED. Change in CPR status during hospitalisation was 5% and upon subsequent admission 14%. For patients discharged with DNACPR orders, reversal of DNACPR status upon subsequent admission was 32%, with uncertainty as to whether this reversal was active or a consequence of a lack of consideration.

Conclusions: The GO-FAR score should only with caution be taken into clinical practice in our setting without update. The updated PIHCA score has a potential to be used in our setting, but external validation and further exploration of clinical use is warranted before implementation. There are shortcomings in the decision process regarding documentation of DNACPR orders and further research is warranted to establish the most effective interventions to strengthen clinical practice. For most patients DNACPR order placement was in line with their preferences, but for a substantial proportion of patients impaired cognition made shared decision impossible. The perspective of risk for cessation of circulation for patients with severe comorbidity can lay in the present situation, but also with the perspective of the near future. One out of ten adult patients received a DNACPR order after emergency admission to a Swedish University hospital. Upon subsequent admissions, for patients with a DNACPR order on previous hospitalisation, reversal of DNACPR status occurred for onethird. This should merit attention as it was uncertain if this reversal was active or represented a lack of consideration.