A practical approach to evidence-based medicine: lessons learned from developing ventilator management protocols

Computerized Decision Support Systems for Mechanical Ventilation in Children

Mechanical ventilation is an effective treatment in the ICU but can have significant adverse effects. Approaches from adult research have been adopted in pediatric critical care despite known differences in respiratory physiology and ICU processes. There continues to be considerable variation in how ventilators are managed. Computerized decision support systems implement explicit protocols, and are designed to make mechanical ventilation management safer, more consistent, and more lung protective. Variable results and low or unknown compliance with protocols and CDSS tools have been reported. To date, there has been limited research regarding CDSS for mechanical ventilation in children.

Pitfalls of counterfactual thinking in medical practice: preventing errors by using more functional reference points

Background

Counterfactual thinking involves mentally simulating alternatives to reality. The current article reviews literature pertaining to the relevance counterfactual thinking has for the quality of medical decision making. Although earlier counterfactual thought research concluded that counterfactuals have important benefits for the individual, there are reasons to believe that counterfactual thinking is also associated with dysfunctional consequences. Of particular focus is whether or not medical experience, and its influence on counterfactual thinking, actually informs or improves medical practice. It is hypothesized that relatively more probable decision alternatives, followed by undesirable outcomes and counterfactual thought responses, can be abandoned for relatively less probable decision alternatives.

Design and Methods

Building on earlier research demonstrating that counterfactual thinking can impede memory and learning in a decision paradigm with undergraduate students, the current study examines the extent to which earlier findings can be generalized to practicing physicians (N=10). Participants were asked to complete 60 trials of a computerized Monty Hall Problem simulation. Learning by experience was operationalized as the frequency of switch-decisions.

Results

Although some learning was evidenced by a general increase in switch-decision frequency across block trials, the extent of learning demonstrated was not ideal, nor practical.

Conclusions

A simple, multiple-trial, decision paradigm demonstrated that doctors fail to learn basic decision-outcome associations through experience. An agenda for future research, which tests the functionality of reference points (other than counterfactual alternatives) for the purposes of medical decision making, is proposed.

Improving Adherence to a Mechanical Ventilation Weaning Protocol for Critically Ill Adults: Outcomes After an Implementation Program

• Background Despite multiple reminders, education sessions, and multidisciplinary team involvement, adherence to an evidence-based mechanical ventilation weaning protocol had been less than 1% in a general systems intensive care unit since implementation.

• Objective To assess the effectiveness of using an implementation program, the Model for Accelerating Improvement, to improve adherence and clinical outcomes after restarting a mechanical ventilation weaning protocol in an adult general systems intensive care unit.

• Methods A prospective comparative design, before and after implementation of the Model for Accelerating Improvement, was used with a consecutive sample of 129 patients and 112 multidisciplinary team members. Clinical outcomes were rate of unsuccessful extubations, rate of ventilator-associated pneumonia, and duration of mechanical ventilation; practice outcomes were staff’s understanding of the mechanical ventilation weaning protocol, perceptions of the practice safety climate, and adherence to the weaning protocol.

• Results After the intervention, the rate of unsuccessful extubations decreased, and staff’s understanding of and adherence to the weaning protocol increased significantly. The rate of ventilator-associated pneumonia, duration of mechanical ventilation, and staff’s perceptions of the practice safety climate did not change significantly.

• Conclusion Implementing the Model for Accelerating Improvement improved understanding of and adherence to protocol-directed weaning and reduced the rate of unsuccessful extubations.

Protocol-driven vs. physician-driven electrolyte replacement in adult critically ill patients

BACKGROUND

The intensive care unit is a dynamic environment, where high numbers of patients cared for by health care workers of different experiences and backgrounds might result in great variability in patient care. Protocol-driven interventions may facilitate timely and uniform care of common problems, like electrolyte disturbances. We prospectively compared protocol-driven (PRD) vs. physician-driven (PHD) electrolyte replacement in adult critically ill patients.

PATIENTS AND METHODS

In the first month of the two-month study, potassium, magnesium, and phosphate levels were checked by a physician before ordering replacement (PHD replacement period). Over the second month, ICU nurses proceeded with replacement according to the protocol (PRD replacement period). We collected demographic data, admission diagnosis, number of potassium, magnesium, and phosphate levels done per day, number of low levels per day, number of replacements per day, time between availability of results to ordering replacement, time to starting replacement, post-replacement levels, serum creatinine, replacement dose, arrhythmias and replacement route.

RESULTS

During the PHD replacement period, 43 patients meeting the inclusion criteria were admitted to the ICU, while 44 were admitted during the PRD month. The mean time (minutes) from identifying results to replacement of potassium, phosphate and magnesium was significantly longer with PHD replacement compared with PRD replacement (161, 187, and 189 minutes vs. 19, 26, and 19 minutes) (P<0.0001). The number of replacements needed and not given was also significantly lower in the PRD replacement period compared with the PHD replacement period (2, 4, and 0 compared with 9, 6 and 0) (P<0.05). No patients had high post-replacement serum concentrations of potassium, phosphate or magnesium.

CONCLUSIONS

This study shows that a protocol-driven replacement strategy for potassium, magnesium and phosphate is more efficient and as safe as a physician-driven replacement strategy.

Protocols for lung protective ventilation

Protocols have a well-established role in clinical research and are increasingly being used to direct routine clinical care. In this article, we review the differing goals of research and clinical protocols and outline the similar process for their development. We use the mechanical ventilation protocol of the ARDS Network trial comparing small with traditional tidal volumes as an example. As a starting point for debate, we also suggest guiding principles and specific components of a protocol for high-frequency oscillatory ventilation.