Contribution of information about acute and geriatric characteristics to decisions about life-sustaining treatment for old patients in intensive care.

BACKGROUND: Life-sustaining treatment (LST) in the intensive care unit (ICU) is withheld or withdrawn when there is no reasonable expectation of beneficial outcome. This is especially relevant in old patients where further functional decline might be detrimental for the self-perceived quality of life. However, there still is substantial uncertainty involved in decisions about LST. We used the framework of information theory to assess that uncertainty by measuring information processed during decision-making. METHODS: Datasets from two multicentre studies (VIP1, VIP2) with a total of 7488 ICU patients aged 80 years or older were analysed concerning the contribution of information about the acute illness, age, gender, frailty and other geriatric characteristics to decisions about LST. The role of these characteristics in the decision-making process was quantified by the entropy of likelihood distributions and the Kullback-Leibler divergence with regard to withholding or withdrawing decisions. RESULTS: Decisions to withhold or withdraw LST were made in 2186 and 1110 patients, respectively. Both in VIP1 and VIP2, information about the acute illness had the lowest entropy and largest Kullback-Leibler divergence with respect to decisions about withdrawing LST. Age, gender and geriatric characteristics contributed to that decision only to a smaller degree. CONCLUSIONS: Information about the severity of the acute illness and, thereby, short-term prognosis dominated decisions about LST in old ICU patients. The smaller contribution of geriatric features suggests persistent uncertainty about the importance of functional outcome. There still remains a gap to fully explain decision-making about LST and further research involving contextual information is required. TRIAL REGISTRATION: VIP1 study: NCT03134807 (1 May 2017), VIP2 study: NCT03370692 (12 December 2017).

Outcome predictors and patient progress following delivery in pregnant and postpartum patients with severe COVID-19 pneumonitis in intensive care units in Israel (OB-COVICU): a nationwide cohort study.

BACKGROUND: A key unresolved controversy in severe COVID-19 pneumonitis in pregnancy is the optimum timing of delivery and whether delivery improves or worsens maternal outcomes. We aimed to assess clinical data on every intensive care unit (ICU) day for pregnant and postpartum women admitted to the ICU with COVID-19, with a particular focus on the days preceding and following delivery. METHODS: In this multicentre, nationwide, prospective and retrospective cohort study, we evaluated all pregnant women who were admitted to an ICU in Israel with severe COVID-19 pneumonitis from the 13th week of gestation to the 1st week postpartum. We excluded pregnant patients in which the ICU admission was unrelated to severe COVID-19 pneumonitis. We assessed maternal and neonatal outcomes and longitudinal clinical and laboratory ICU data. The primary overall outcome was maternal outcome (worst of the following: no invasive positive pressure ventilation [IPPV], use of IPPV, use of extracorporeal membrane oxygenation [ECMO], or death). The primary longitudinal outcome was Sequential Organ Failure Assessment (SOFA) score, and the secondary longitudinal outcome was the novel PORCH (positive end-expiratory pressure [PEEP], oxygenation, respiratory support, chest x-ray, haemodynamic support) score. Patients were classified into four groups: no-delivery (pregnant at admission and no delivery during the ICU stay), postpartum (ICU admission ≥1 day after delivery), delivery-critical (pregnant at admission and receiving or at high risk of requiring IPPV at the time of delivery), or delivery-non-critical (pregnant at admission and not critically ill at the time of delivery). FINDINGS: From Feb 1, 2020, to Jan 31, 2022, 84 patients were analysed: 34 patients in the no-delivery group, four in postpartum, 32 in delivery-critical, and 14 in delivery-non-critical. The delivery-critical and postpartum groups had worse outcomes than the other groups: 26 (81%) of 32 patients in the delivery-critical group and four (100%) of four patients in the postpartum group required IPPV; 12 (38%) and three (75%) patients required ECMO, and one (3%) and two (50%) patients died, respectively. The delivery-non-critical and no-delivery groups had far better outcomes than other groups: six (18%) of 34 patients and two (14%) of 14 patients required IPPV, respectively; no patients required ECMO or died. Oxygen saturation (SpO2), SpO2 to fraction of inspired oxygen (FiO2) ratio (S/F ratio), partial pressure of arterial oxygen to FiO2 ratio (P/F ratio), ROX index (S/F ratio divided by respiratory rate), and SOFA and PORCH scores were all highly predictive for adverse maternal outcome (p<0·0001). The delivery-critical group deteriorated on the day of delivery, continued to deteriorate throughout the ICU stay, and took longer to recover (ICU duration, Mantel-Cox p<0·0001), whereas the delivery-non-critical group improved rapidly following delivery. The day of delivery was a significant covariate for PORCH (p<0·0001) but not SOFA (p=0·09) scores. INTERPRETATION: In patients who underwent delivery during their ICU stay, maternal outcome deteriorated following delivery among those defined as critical compared with non-critical patients, who improved following delivery. Interventional delivery should be considered for maternal indications before patients deteriorate and require mechanical ventilation. FUNDING: None.

On predictions in critical care: The individual prognostication fallacy in elderly patients.

Predicting the future course of critical conditions involves personal experience, heuristics and statistical models. Although these methods may perform well for some cases and population averages, they suffer from substantial shortcomings when applied to individual patients. The reasons include methodological problems of statistical modeling as well as limitations of cross-sectional data sampling. Accurate predictions for individual patients become crucial when they have to guide irreversible decision-making. This notably applies to triage situations in response to a lack of healthcare resources. We will discuss these issues and argue that analysing longitudinal data obtained from time-limited trials in intensive care can provide a more robust approach to individual prognostication.

The selective pulmonary vasodilatory effect of inhaled DETA/NO, a novel nitric oxide donor, in ARDS-a pilot human trial.

OBJECTIVES: To examine the effects of inhaled NONOates in patients with acute respiratory distress syndrome (ARDS). DESIGN: Case-series, phase I clinical trial. SETTING: A multidisciplinary intensive care unit in a tertiary teaching hospital. PATIENTS: Five consecutive patients with ARDS (men; age range, 47-76 years). MEASUREMENTS: DETA/NO (150 micromol) was aerosolized into the lungs of patients on mechanical ventilation via the endotracheal tube over 20 minutes. Hemodynamic parameters were measured and blood samples were taken before, during, and after inhalation. RESULTS: Compared to baseline values, pulmonary vascular resistance decreased until the end of the study period (180 minutes) while intrapulmonary shunting decreased significantly up to 45 min after DETA/NO aerosol administration. Inhaled DETA/NO had no effect on the systemic circulation (systemic blood pressure or cardiac output). CONCLUSIONS: Inhaled DETA/NO is a selective pulmonary vasodilator in patients with ARDS. However, a larger number of patients is required to confirm the findings of this pilot study.

Closed-loop glucose control in critically ill patients using continuous glucose monitoring system (CGMS) in real time.

A study was conducted to determine if continuous subcutaneous glucose monitoring (from MiniMed CGMS) could be used in real-time to control blood sugar level (BSL) in patients with critical illness. A closed-loop control system was constructed to use CGMS in a real-time manner, coupled with a proportional integral (PI) control algorithm based on a sliding scale approach, for automatic intravenous infusion of insulin to patients. A total of five subjects with high BSL (> 10 mmol/L) participated in formal studies of the closed-loop control system. Subjects were recruited from critically ill patients in the intensive care unit (ICU) after informed consent was obtained. Error grid analysis showed that 64.6% of the BSL readings as determined in real time using CGMS sensor, when compared to conventional BSL measurements on blood drawn from an arterial line, was clinically accurate (i.e., < 20% deviation from glucometer value). In the five patients who underwent closed-loop control, the controller managed to control only one patient's glycaemia without any manual intervention. Manual intervention was required due to the real-time sensor reading deviating more than 20% from the glucometer value, and also as a safety mechanism. Test on equality of mean and variance for BSL attained prior to, during, and post trial showed that the controller's performance was comparable to manual control. We conclude that the automatic sliding scale approach of closed-loop BSL control is feasible in patients in intensive care. More work is needed in the refinement of the algorithm and the improvement of real-time sensor accuracy.

Brain death determination in Australia and New Zealand: a survey of intensive care units.

BACKGROUND: The Australian and New Zealand Intensive Care Society (ANZICS) guidelines for the determination of brain death involve clinical testing and/or the use of brain blood flow analysis techniques. Recently, there has been professional and lay discussion regarding the role of brain blood flow analysis in the determination of brain death. OBJECTIVE: To determine the current practices in Australian and New Zealand intensive care units for the determination of brain death. METHODS: All adult ICUs in Australia and New Zealand accredited for training in intensive care by the College of Intensive Care Medicine of Australia and New Zealand were surveyed to determine the unit size, whether certification of brain death occurs in that unit, and the method routinely used to determine brain death if there were no contraindications to clinical testing. RESULTS: There were 47 responses (53% response rate). Of the surveyed units, 89% of units used two sets of clinical tests for brain death determination; 9% used one set of clinical testing and one imaging technique; and 2% of units used one imaging technique only. When an imaging technique was used, four units used radionuclide imaging, one unit used magnetic resonance imaging and one unit used computed tomography angiography. CONCLUSIONS: Two sets of clinical testing is the most common method for determining brain death in Australian and New Zealand ICUs. A minority of units used some form of brain blood flow imaging. Based on these findings, all brain death certification is in accordance with ANZICS guidelines.

Extracorporeal membrane oxygenation for critically ill patients with influenza A (H1N1) 2009: a case series.

In this case series, we report on five patients with influenza A (H1N1) who received extracorporeal membrane oxygenation (ECMO) treatment between July and December 2009 in the intensive care unit of Sir Charles Gairdner Hospital in Perth, Western Australia. In considering these cases, we highlight the indications, risks and potential benefits associated with ECMO, whose role remains, as yet, largely undefined in the setting of H1N1 critical illness.

Equitable resource allocation in the intensive care unit: a descriptive ethical case.

A patient with respiratory failure due to undiagnosed tuberculosis in the presence of HIV infection presents to the ICU in a foreign country. This raises many ethical questions, quite apart from the medical management issues raised by the patient's serious condition. Six of these ethical questions have been presented to leading physicians and an ethicist, from a range of national, cultural and religious backgrounds, for their comment.