Sleep Loss, Fatigue and Medical Training Susan M. Harding, MD Professor of Medicine Medical Director, Sleep-Wake Disorders Center University of Alabama at Birmingham University Hospital Housestaff 1982-83
Learning Objectives • List factors that put you at risk for sleepiness and fatigue. • Describe the impact of sleep loss on residents’ personal and professional lives. • Recognize signs of sleepiness and fatigue in yourself and others. Adapt alertness management tools and strategies for yourself and your program.
Residency Training Over Past 5 Decades • Call every other night • Call every 3rd night, then every 4th night • Work is more stressful • “Less sick” patients are out of the hospital • Heightened intensity of patient care • Lower margin for error • Constant paging interruptions disrupt work flow
State of Sleepiness Prior to ACGME Limiting Resident Work HoursRosen IM et al. Acad Med 2004; 79:407 • Survey of 79 Internal Medicine residents at the Univ of Pennsylvania, June 2001 • 34% experienced acute sleep deprivation • 64% experienced chronic sleep deprivation • Dozing while performing work-related tasks • 69% writing notes • 61% reviewing medication lists • 51% interpreting labs • 46% writing orders
ACGME Work Hour RulesEffective July 1, 2003 • Restricts work hours to < 80 hrs/week avg • < 30 hours of continuous coverage at any 1 time • Should have 10 hours off between shifts • Stimulus – quality of care, but minimal data was available linking fatigue to errors • Different people have different “inflection points” concerning sleep deprivation
ACGME Work Hour Rules • Made everyone re-examine their educational programs • Provided impetus to examine ways to improve the system • Emphasizes the need for more effective team work • Brought up continuity of care and transfer of care issues with frequent “hand offs” • What happens after training?
ACGME Work Hour Rules:Potential StressorsRyan J. Ann Intern Med 2005; 143:82 • Increased number of patient hand offs • Cross coverage • Communication and team work • Increasing paperwork • Pressure to get done and get out • Rushing from task to task w/out time to think and learn • Resident comraderie
“No, I’ve just come to start my overnight call. Why do you ask?” ACP Internist, Jan 2009
Institute of Medicine’s (IOM) Recommendations (at Congress’ Request)December 2008
Cost of Implementing IOM’s Recommendations • 1.7 billion per yr (1/4 of cost is bringing non-compliant programs into compliance – 8.8% of programs • Create and fill fulltime positions for: • 229 nursing aides • 45 laboratory technicians • 320 licensed vocational nurses • 5984 NPs or PAs • 5001 attending physicians OR… - 8247 additional residency positions
“There are fundamental effects from sleep loss which permeate performance on virtually all cognitive and sustained attention tasks” Courtesy of Journal for Respiratory Care Practitioners, Jun/Jul 1998
Regulation of Sleep and Wakefulness • Homeostatic drive for sleep (previous sleep amounts, duration of wakefulness) • Circadian influence (24 hour clock, alertness peaks and troughs) • Environmental factors: feedback, reinforcement, task nature/length/complexity • Individual variables: motivation, emotional context; physical activity; age, individual variation sleep needs and vulnerability
Effects of Sleep Deprivation: Experimental Settings • Neurobehavior impairment similar for short-term (24-48 hrs) total sleep deprivation and chronic partial sleep restriction (<6 hrs/night for > 1 week) • Sleep “debt”: Effects of chronic partial sleep loss are cumulative; not reversed in a single night • Perception of sleepiness is less affected than measured sleepiness • Circadian influence
Effects of Sleep Deprivation: Experimental Findings • Mood universally affected • Impairment in vigilance, delayed and immediate recall • Complex tasks and problem-solving affected; performance deteriorates with time-on-task; task duration; perseveration and poor prioritization • Maintenance of accuracy at the expense of speed
Effects of Sleep Deprivation: Experimental Findings • Learning of new tasks compromised • Motivation affected • “Lapsing”: variability in task performance related to interruption of sustained attention from “microsleeps” • Variability in performance may be more affected than average quality
Factors Increasing Fatigue • Prolonged wakefulness (>15 continuous hrs) • Reduced or disrupted sleep • Shift variability • Volume and intensity of work
Sleep Restriction Banks S, Dinges DF. J Clin Sleep Med 2007; 3:519 Inter-individual differences, BUT… • Sleepiness – dose response effect • Lapses of attention and vigilance on tasks • More errors on simulated driving • Response slowing • Spatial learning problems • Decrease in behavioral alertness with “microsleeps” • Psychomotor vigilance test performance impaired • Working memory performance impaired • Mood problems • Cognitive and executive function impairment
Sleep Restriction Banks S, Dinges DF. J Clin Sleep Med 2007;3:519 • Elevated BP • Reduced glucose tolerance • Sympathetic nervous system activation • Reduced leptin levels (appetite) • Increased inflammatory markers (IL-6, TNFα, CRP) • Obesity Physiological consequences…
Sleep Restriction Banks S, Dinges DF. J Clin Sleep Med 2007;3:519 • Obesity • Insulin resistance • Cardiovascular events (epidemiological studies) • Mortality • Common cold susceptibility (Cohen S et al. Arch Intern Med 2009;169:62)
Sleep Deprivation: Effects on Mood • Increased dysphoria/depression anger/hostility; decreased motivation • Correlation with sleep amounts • Effects last up to 48 hrs post-call • Independent association with night shift
Sleep Deprivation –Socioeconomic Consequences… • More than 1,000,000 motor vehicle accidents annually are sleep-related • Disasters such as Chernobyl, Three Mile Island, Challenger, Bhopal, and Exxon Valdez were officially attributed to errors in judgment induced by sleepiness or fatigue
Three Mile Island and Chernobyl Disasters 1. US Nuclear Regulatory Commission. Report on the Accident at Chernobyl Nuclear Power Station. Washington DC: US Government Printing Office; 1987. 2. Moss TH, Sills DL. The Three Mile Island nuclear accident: lessons and implications. Ann NY Acad Sci 1981; 365:1-341 • Early morning human error • Fatigue-related accidents Deserted city of Prypiyat with Chernobyl nuclear reactor in the background
Exxon Valdez GroundingNTSB. Marine Accident Report – Grounding of the US Tankership EXXON VALDEZ on Bligh Reef, Prince William Sound, Near Valdez, Alaska, March 24th, 1989. Washington DC: NTSB/March-90/04 “…probable cause of the grounding of the Exxon Valdez was the failure of the third mate to properly maneuver the vessel because of fatigue and excessive workload…”
Epworth Sleepiness ScaleJohns MW. Sleep 1994; 17:703-710 0 - WOULD NEVER DOZE 1 - SLIGHT CHANCE OF DOZING 2 - MODERATE CHANCE OF DOZING 3 - HIGH CHANCE OF DOZING Sitting reading (Range 0 – 24) Watching TV Sitting inactive in public Passenger in a car for 1 hour Sitting and talking Sitting quietly after lunch In a car, while stopped for a few minutes in traffic
Epworth Sleepiness Scale Scores (0-24 range)Papp KK, et al. Acad Med 2004; 79:394-402 : Sleepiness in residents is equivalent to that found in patients with serious sleep disorders (normal < 10)
Stanford Sleepiness Scale An introspective measure of sleepiness – The Stanford Sleepiness Scale (SSS)
Despite this, the problem of sleepiness and fatigue in residency is under-estimated.
MYTH: “It’s the really boring noon conferences that put me to sleep.” FACT: Environmental factors (passive learning situations, room temperature, low light levels, etc.) may unmask, but DO NOT CAUSE SLEEPINESS!
Conceptual Framework(in Residency) Insufficient Sleep (on call sleep loss/ inadequate recovery sleep) Fragmented Sleep (pager, phone calls) Excessive Daytime Sleepiness Circadian Rhythm Disruption (night float, rotating shifts) Primary Sleep Disorders (sleep apnea, etc)
Sleep Needed vs Sleep Obtained • Myth: “I’m one of those people who only needs 5 hours of sleep, so none of this applies to me.” • Fact:Individuals may vary somewhat in their tolerance to the effects of sleep loss, but are not able to accurately judge this themselves. • Fact: Human beings need 8 hours of sleep to perform at an optimal level. • Fact: Getting less than 8 hours of sleep starts to create a “sleep debt” which must be paid off.
Sleep Fragmentation Affects Sleep Quality NORMAL SLEEP = Paged MORNING ROUNDS ON CALL SLEEP
The Circadian Clock Impacts You • It is easier to stay up later than to try to fall asleep earlier. • It is easier to adapt to shifts in forward (clockwise) direction. (day evening night) • Night owls may find it easier to adapt to night shifts.
Interaction of Circadian Rhythms and Sleep Sleep Homeostatic drive (Sleep Load) Wake Sleep Alertness level Circadian alerting signal 3 pm 9 AM 3 AM 9 PM 9 AM Time
Sleep Disorders: Are you at Risk? • Physicians can have sleep disorders too! • Obstructive sleep apnea • Restless legs syndrome • Periodic limb movement disorder • Learned or “conditioned” insomnia • Medication-induced insomnia
Adaptation to Sleep Loss • Myth: “I’ve learned not to need as much sleep during my residency.” • Fact: Sleep needs are genetically determined and cannot be changed. • Fact: Human beings do not “adapt” to getting less sleep than they need. • Fact: Although performance of tasks may improve somewhat with effort, optimal performance and consistencyof performance do not!
Consequences of Chronic Sleep Deprivation Sleep is a vital and necessary function, and sleep needs (like hunger and thirst) must be met
Impairment Across Specialties • Surgery: 20% more errors and 14% more time requiredto perform simulated laparoscopy post-call (two studies) Taffinder NJ et al, Lancet 1998; 352:1191; Grantcharov TP et al. BMJ 2001; 323:1222 • Internal Medicine: efficiency and accuracy of ECG interpretation impaired in sleep-deprived interns Lingenfelser T et al. Med Education 1994;28:566 • Pediatrics:time required to place an intra-arterial line increased significantly in sleep-deprived residents Storer JS et al, Acad Med 1989; 64:291989
Surgery Residents:Laparoscopic Skills Suffer on the First Night Shift • Technical skills assessed on 2 tasks • Took longer (p=.002) and made more errors (p=.025) on their first night shift • Were less economical with movements on the first night shift • Some improvement noted during subsequent shifts Lesson: Prepare for night shift, realize your limitations Leff DR et al. Ann Surg 2008;247:530 21 residents trained on a virtual reality surgical simulator:
Across Tasks • Emergency Medicine: significant reductions in comprehensiveness of history & physical exam documentation in second-year residents Bertram DA. NY State J Med 1998; 88:10-15 • Family Medicine: scores achieved on the ABFM practice in-training examnegatively correlated with pre-test sleep amounts Jacques CJ et al. J Fam Pract 1990; 30:223-229
Impact on Professionalism “Your own patients have become the enemy…because they are the one thing that stands between you and a few hours of sleep.”
Work Hours, Medical Errors, and Workplace Conflicts by Average Daily Hours of Sleep* Percent % * Baldwin DJr et al. Acad Med 2003;78:1154 Hours of Sleep
Limiting Resident Work Hours:Impact on Patient SafetyFletcher KE, et al. Ann Intern Med 2004:141 • Insufficient evidence • 7 studies had an intervention to reduce work hours and assessed patient safety outcomes (4 retrospective, 3 prospective studies) • Limitations on study design, diversity of interventions and possibly publication bias
Do ACGME Duty Hour Rules Impact Hospital Mortality? No? Volpp KG et al. JAMA 2007;298:975 • Compared mortality rates for all Medicare pt admissions to teaching hospitals from 2000-2003 (pre duty hours reform) to 2003-2005 (after duty hour reform) • ACGME duty hours reform was not associated with either worsening or improvement in mortality during the first 2 years after implementation
Do ACGME Duty Hour Rules Impact Hospital Mortality? Yes? • Compared mortality rates for all VA Hospitals from 2000-2003 and 2003-2005 • Duty hour rules were associated with improvement in mortality for 4 common medical conditions (AMI, CVA, GI bleed, CHF)—but not for surgical conditions Volpp KG et al. JAMA 2007; 298:984
Serious Medical Errors in the ICULandrigan CP et al. N Engl J Med 2004; 351:1838 • Prospective randomized trial of interns • Traditional schedule with an extended (> 24 hr) work shift every 3rd night (3 interns) • 77 to 81 hrs/wk up to 34 hrs of continous work • Interventional schedule where one intern worked 7 am to 10 pm on call and another worked 9 pm to 1 pm (4 interns) • 60 to 63 hrs/wk with up to 16 continous working hours • Examined incidence of serious medical errors
Serious Medical Errors in the ICULandrigan CP et al. N Engl J Med 2004; 351:1838 • Interns on the traditional schedule • Made 36% more serious medical errors • Made 21% more serious medication errors • Made 5.6 times as many serious diagnostic errors • Eliminating extended work shift and reducing the number of work hours per week can reduce serious medication errors in the ICU