By Mike Lauria, Cliff Reid, and Scott Weingart
It is even better to act quickly and err than to hesitate until the time of action is past. –Carl von Clausewitz, Vom Kriege
In the special operations community we accepted that certain dangerous situations develop at a speed that exceeds our analytical capability. This understanding came to be by many hard-learned lessons, paid for in blood by our predecessors. As a result, our training evolved to incorporate Immediate Actions Drills (IADs).
These IADs were trained, habitual reflex action patterns to various potentially lethal, time-sensitive situations. For example, if a team was on patrol and someone started shooting at them from the team’s right flank, the immediate response was to call out “contact right”. The team would quickly lay down suppressive fire in the direction of the threat and rapidly execute a standard tactical maneuver (rehearsed dozens of times in training). This maneuver might be to break into smaller units and bound back to safe location or even bound forward and attack the assailant. Regardless of the particular tactical maneuver, the strategy represents sound tactics and is widely accepted. The key is that we know the stress of a sudden attack can be overwhelming and chaos can ensue unless the team has a well-rehearsed, high fidelity psychomotor program that can reliably be executed.
Another example is the instance of a weapon malfunction. When you’re engaged in a fight and you pull the trigger on a weapon system, you expect the weapon to fire. If you pull the trigger and all you hear is a soft “click”, you’re in trouble. At this point, you don’t have time to carefully examine the weapon system and diagnose the precise problem. We train people to execute a precise motor sequence aimed at empirically addressing the very common causes of a weapon to malfunction. The mantra we teach is “SLAP, RACK, BANG!” First, “slap” the bottom of the magazine (loosely or improperly seated magazines), then “rack” the slide or charging handle (removing any faulty or jammed rounds), and finally pull the trigger (“bang”).
There are certain situations in resuscitation that are very time-sensitive and require immediate action. Often, the challenge is that we train people to diagnose critical, life-threatening problems the same way we teach them to diagnose routine ones. The fact is that in very stressful situations, our brains don’t function the same way they do normally. As a result, it may be worthwhile to think through these particular clinical circumstances in advance, consider the very likely causes of the situation, and train people to empirically address these issues using a fixed, reflexive action pattern.
Critical Effects of Stress Response
The justification for simple, hard-wired fixed motor response patterns is largely based on the functional deterioration of numerous faculties during stressful situations.
During stressful situations humans experience attentional narrowing. In the world of engineering psychology, this is referred to as “increased selectivity.”1 People have a tendency to lose global situational awareness and focus on particular tasks. Evidence demonstrates this can be a result of numerous stressors including noise, visual distractions, or time pressure.2,3 Under these circumstances, study participants have shown decreases in detection of objects in the peripheral vision.4 Furthermore, the problem is more than just a decrease in visual field or breadth of what an individual’s mind can attend to, it is also a failure to focus on the most appropriate information. As it turns out, we seem to focus on what we perceive to be the most important information5 (an adaptive cognitive triage mechanism of sorts), but this could be dangerous if the stimulus that grabs our attention is not the most critical to actually solving the clinical puzzle presented.6 Not surprisingly, the fewer pieces of information we have to process, the lower the cognitive load, and the lesser the tunneling effect.7
This attentional narrowing is further complicated by increased perseveration: continuing or repeating a given action or plan that one has recently used or regularly applies. As stress increases and cognitive faculties deteriorate, people are more likely to continue trying the same unsuccessful solution despite clear evidence of its failure.8,9 Cognitive psychologists have suggested this aligns with current understanding of human behavior: people tend to default to what is known or familiar in times of stress. Thus, in a problem solving situation, the range of options is not only narrow, but we fail to explore other solutions even if the narrow range of options are failing.10,11 The result is a potentially dangerous enhanced effect of confirmation bias.12
Stress also decreases information processing and working memory.13,14,15 It affects both internal dialogue16 (keeping information at hand) and also causes increased distraction of attention.17 The compromise to working memory is more pronounced the more complex the task. Researchers have demonstrated marked effects on complex problem solving18 and decision problems that involve special visualization for successful resolution.19 So, our ability to perform clinically important cognitive tasks (such as thinking about the underlying pathological process) is inhibited, to an extent, and takes more time.
Adapting to Stressful Situations
Human beings naturally develop strategies that will, consciously and unconsciously, allow them to cope with perceived stress. In the realm of Human Factors Engineering, this is referred to as strategic control.1 A number of mechanisms have been described by authors such as Hockey, Maule, and Svenson.
One method is called “Resource Recruitment.” This suboptimal adaptation entails working faster or harder (recruiting more cognitive or physical effort) to quickly achieve an outcome.15 While speed increases, accuracy suffers and techniques are often error-prone. Another strategy is removal of an offending stressor (such as silencing an alarm or asking a boisterous family member to leave). While this is very effective, it is not often feasible.
Finally, humans can employ strategic adaptation. These are cognitive or behavioral techniques that have been developed to cope with certain situations. In particular, developing heuristics or simplified decision making tools can, in some situations, be very effective at quickly and accurately completing a task.20,21,22 Over time, as individuals gain valuable experience and feedback, the repertoire of tools can be refined. With fine-tuning of these techniques, performance under stress can actually improve.
Observation of this adaptation has been applied to system design with success. Results of investigations from decision making in high stress situations have informed scientists in the field of human factors and ergonomics. Systems are designed to be simpler and more streamlined to facilitate recognition and processing. For example, decision trees and algorithms that are simplified to make cognitive processing easier are more effective in situations with time pressure.23,24 Digital displays that reduce visual clutter and only provide salient information seem to buffer the deteriorating effects of stress.25 Simplified displays that reduce the need to visually search for information and guide attention to key information are likewise effective.1,26
Emergency Reflex Action Drills: Designing the Human System
Emergency Reflex Action Drills (ERADs, pronounced ē – rads) are specifically designed action sequences intended to execute clinical interventions with minimal cognitive load in the setting of marked time pressure. These drills are tailored to respond to particular situations. They are carefully developed with thought, intention, and analysis of the available literature to consider the risks and benefits. In essence, the “thinking” is done in advance so that during a true emergency the programmed cognitive and action sequence can be applied.
ERADs take advantage of two critical aspects of behavior and cognition to mitigate the effects of workload and stress. First, by creating a reflexive, programmed motor response the cognitive load decreases in the moment. ERADs are relatively simple, and simplicity can be key to improving performance under stress.23,24 Less neurological energy and fewer cognitive resources are required27,28,29 which addresses the issue of low working memory under stress. Second, the routine action which follows a specific cue (loss of pulses, inability to visualize the glottis during laryngoscopy, etc.) circumvents the need to triage tasks and avoids perseveration on ineffective or incorrect tasks because the programmed response removes the necessity of these processes.
Finally, it is worth mentioning that Human Factors experts have highlighted the utility of “adaptive automation”30: technologies that adjust to decrease the cognitive load on humans during times when workload or psychological stresses are increased. These systems offload (largely surveillance and monitoring) processes to allow the human brain to focus on the most critical decisions. In a sense, ERADs are behavioral correlates of “adaptive automation.” They are automatic fixed action patterns employed to prevent or at least stave off catastrophic results.
Specific ERAD Examples
- Response to Grade III or IV Cormack-Lehane View During Intubation – George Kovacs (@kovacsgj) developed an excellent ERAD in response to Grade III/IV view on direct laryngoscopy in three steps: 1) lift the occiput beyond sniffing position and align axes, 2) use external laryngeal manipulation to optimize view, 3) Use Two Hand lifting if unable to manage with one hand. Or as Scott teaches this ERAD, HEAD-NECK-HANDS
- Response to Sudden and Profound Hypotension – Scott uses this immediate action in response to a patient whose hemodynamics suddenly deteriorate and is peri-arrest: 1) grab an amp of cardiac epinephrine (100 mcg/cc) from the code cart 2) push 0.5 cc to maintain hemodynamics while you determine the cause for acute decompensation and develop a plan for definitive fix. CART-EPI-HALF
- Response to Hypoxia in the Awake Patient – Rich Levitan (@airwaycam) teaches the OOPS mnemonic to address hypoxia: 1) OXYGEN ON via nasal cannula, 2) PULL the jaw forward/jaw thrust 3) SIT patient up.
- Response to Cardiovascular Collapse in Patient on ECMO – The @EDECMO team suggest the following as immediate response to blood spraying around the room with a patient on ECMO: 1) clamp the arterial cannula 2) clamp the venous cannula 3) Prepare Epinephrine & Change Vent Settings. CLAMP-CLAMP-RESUSCITATE
- Response to Profound Deterioration on a Ventilator – Scott teaches this 3 part ERAD to overcome vent manipulation fixation as the patient crashes: 1) Bag with BVM (ask for a PEEP valve as soon as possible) 2) Call for Help—often fixing this problem is a 2-person job 3) Troubleshoot with DOPES. BAG-HELP-DOPES
6. Response to Loss of Palpable Pulses in a Blunt Polytrauma Patient – The Sydney HEMS team will 1) Attempt to arrest massive haemorrhage, 2) Perform a ‘cold’ tracheal intubation, 3) Make bilateral open thoracostomy incisions, and 4) infuse packed red blood cells. STOP-TUBE-CUT-INFUSE
- Stress (threat mindset) results in decreased working memory (cognitive bandwidth), attentional narrowing, decreased information triage capability, and psychomotor perseveration.
- Strategic Adaptation is systematic cognitive behavioral modification to deal with stressful situations.
- Emergency Reflex Action Drills (ERADs) are automatic, habitual fixed action patterns designed to empirically address dangerous clinical situations.
We would love to hear what you guys think. What kind of ERADs do you use in different clinical situations? How do you teach them to your peers and trainees?
- Wickens CD, Hollands JG, Banbury S, Parasuraman R. Engineering Psychology and Human Performance. New York, NY: Taylor & Francis; 2015.
- Kahneman D. Attention and Effort. Englewood Cliffs, NJ: Prentice Hall; 1973.
- Hockey GR. Effect of loud noise on attentional selectivity. Quart J Exper Psychol. 1970;22(1):28-36.
- Weltman G, Smith JE, Egstrom GH. Perceptual narrowing during simulated pressure-chamber exposure. Hum Factors. 1971;13(2):99-107.
- Duggan GB, Payne SJ. Text skimming: The process and effectiveness of foraging through text under time pressure. J Exp Psychol Appl. 2009;15(3):228.
- Broadbent DE. Decision and Stress. New York, NY: Academic Press; 1971.
- Edland A. On Cognitive Processes Under Time Stress: A Selective Review of the Literature on Time Stress and Related Stress. Reports from the Department of Psychology. University of Stockholm, Sweden. 1989.
- Zakay D. The impact of time perception processes on decision making under time stress. In: Svenson O, Maule AJ, eds. Time pressure and stress in human judgment and decision making. Boston, MA: Springer; 1993: 59-72.
- Luchins AS. Mechanization in problem solving: The effect of Einstellung. Psychol Monographs. 1942;54(6): i-95.
- Shanteau J, Dino GA. Environmental stressor effects on creativity and decision making. In: Svenson O, Maule AJ, eds. Time pressure and stress in human judgment and decision making. Boston, MA: Springer; 1993: 293-308.
- Woods DD, Johannesen LJ, Cook RI, Sarter NB. Behind the human error: Cognitive systems, computers, and hindsight. State-of-the-Art Report Crew System Ergonomics Integration Analysis Center (CSERIAC). Wright-Patterson AFB, OH. 1994: 94-01
- Jensen RS. Pilot judgement: Training and evaluation. Hum Factors. 1982;19:535-547.
- Davies DR, Parasuraman R. The Psychology of Vigilance. London, UK: Academic Press; 1982.
- Wachtel PL. Anxiety, Attention, and Coping with Threat. J Abnorm Psychol. 1968; 73: 137-143.
- Hockey GRJ. Compensatory Control in the Regulation of Human Performance Under Stress and High Workload: A Cognitive-Energetical Framwork. Bio Psychol. 1997;45(1-3): 73-93.
- Poulton EC. Continuous noise interferes with work by masking auditory feedback and inner speech. Appl Ergo. 1976;7(2):79-84.
- Berkun MM. Performance decrement under psychological stress. Hum Factors. 1964;6:21-30.
- Wickens CD, Stokes AF, Barnett B, Hyman F. The effets of stress on pilot judgment in a MIDIS simulator. In: Svenson O, Maule AJ (Ed.). Time Pressure and Stress in Human Judgement and Decision Making. New York, NY: Plenum Press; 1993: 271-292.
- Stokes AF, Raby M. Stress and cognitive performance in trainee pilots. In: Proceedings of the 33rd Annual Meeting of the Human Factors Society. Santa Monica, CA: Human Factors Society; 1989: 883-887.
- Maule AJ, Hockey GR, Bdzola L. Effects of time-pressure on decision-making under uncertainty: changes in affective state and information processing strategy. Acta Psychol. 2000;104(3):283-301.
- Johnston JH, Driskell JE, Salas E. Vigilant and hypervigilant decision making. J App Psychol. 1997;82(4):614.
- Flin R, Salas E, Strub M, Martin L. Decision-Making Under Stress: Emerging Themes and Applications. Burlington, VT: Routledge; 2017.
- Driskell JE, Salas E, Hall JK. The effect of vigilant and hypervigilant decision training on performance. Paper presented at the Annual Meeting of the Society of Industrial and Organizational Psychology. Nashville, TN. 1994.
- Lusk CM. Assessing components of judgement in an operational setting: The effects of time pressure on aviation weather forecasting. In: Svenson O, Maule AJ (Ed.). Time Pressure and Stress in Human Judgement and Decision Making. New York, NY: Plenum Press; 1993: 271-292.
- Schwartz DR, Howell WC. Optional stopping performance under graphic and numeric CRT formatting. Hum Factors. 1985;27(4):433-44.
- Burns CM, Skraaning Jr G, Jamieson GA, Lau N, Kwok J, Welch R, Andresen G. Evaluation of ecological interface design for nuclear process control: situation awareness effects. Hum Factors. 2008;50(4):663-79.
- Graybiel AM. Building action repertoires: memory and learning functions of the basal ganglia. Curr Opin Neurobiol. 1995;5(6):733-741.
- Graybiel AM, Aosaki T, Flaherty AW, Kimura M. The basal ganglia and adaptive motor control. Science. 1994;265(5180):1826-1831.
- Graybiel AM. Habits, rituals, and the evaluative brain. Ann Rev Neurosci. 2008; 31: 359-387.
- Parasuraman R, Hancock PA. Mitigating the Adverse Effects of Workload, Stress, and Fatigue with Adaptive Automation. In: Hancock PA, Szalma JL, eds. Performance Under Stress. Burlington, VT: Ashgate Publishing Limited; 2008: 45-59.