NEW TECHNOLOGIES
| ROBOTICS AND SIMULATION —Richard M. Satava, MD, Professor of Surgery, University of Washington, School of
Medicine, Program Manager, Advanced Biomedical Technologies Defense Advanced Research Projects Agency, and Special
Assistant, Advanced Medical Technologies, United States Army Medical Research and Materiel Command, Seattle,
WA
|
| Emerging technologies: fundamentally changing how surgery practiced, eg, laparoscopic surgery; information basis for
practice of surgery; why robots important—in industry, robots perform 12 to 15 times faster and with 8 to 12 times
greater precision than humans; health care only industry that does not have computer representation of product (patient);
“Virtual Soldier”—speaker’s program; building holographic electronic representation to replace medical record; 3-D image
based on total body scan from computed tomography (CT) and magnetic resonance imaging (MRI); incorporates physiology
and biochemistry of individual to create computerized representation; can practice surgical procedure on
representation rather than on individual; surgeons need to look at devices not as machines but as information systems, eg,
CT scanner not imaging device but information system with “eyes”; in essence, surgeon becomes information manager
|
| Surgical robotic system: able to perform open surgery, minimally invasive surgery, robotic surgery, remote telesurgery,
preoperative planning, and even surgical rehearsal; can use virtual representation in simulation training; speaker’s
view—robotic surgery inevitable; just question of time and size of market niche; will not replace everything (eg, open
surgery and laporoscopic surgery will never go away)
|
| Change in instrumentation: from mechanical to energy-directed; instead of scissors, scalpels, and clamps, will use
high-intensity focused ultrasonography (HIFU) and femtosecond lasers; with instruments— can combine therapy with
diagnostics; from minimally invasive to noninvasive; from macrosurgery (entire body or single organ) to microsurgery
(individual cells); with HIFU—able to stop internal bleeding without performing surgery; with femtosecond laser—
pulsing laser onto cell membrane opens ion channels without injuring cell; can go inside cell with tools and manipulate
individual organelles (eg, mitochondria) or inside nucleus and manipulate chromosomes (in future, may be able to manipulate
DNA and change genetic sequences)
|
| Transgastric or natural orifice surgery: may be practiced within decade; going back to flexible endoscopy; stomach
perforated purposely, and with multifunctional instruments at end of flexible endoscope, able to reach inside abdominal cavity;
also experimenting on suturing instruments with flexible endoscope
|
| Operating room (OR) of future: without lights, people, and anesthesia; ceiling as source of light—no longer passive
structure but “active participant”; will consist of one thousand light-emitting diodes (LEDs; controllable by computer)
placed on panels; voice commands to change direction of focus; Penelope—computer-aided design/computer-aided
manufacturing (CAD/CAM) prototype of surgical scrub nurse (robotic nurse); voice-activated; equipped with vision detection
(can find instruments and hand them to surgeon); procedures—in future, patient brought to holding area and put
to sleep in position for surgery; total body scan performed; patient then taken to OR in sterile condition; surgeon at surgical
work station can practice critical part before actual surgery, viewing exact anatomy that will be encountered; surgical
rehearsal errors made on image; at each step of way, accountability taking place; OR of future will be totally integrated
information system, controlled by surgeon from work station
|
| Military: interested in building robots for deployment in battlefield; future vision (based on systems/prototypes already
developed)—experimental evacuation vehicle would transport wounded soldier to armored ambulance; ambulance
houses intensive care unit equipped with robotics and mechanized systems; immediate surgical treatment of wounds, and
evacuation via unmanned air vehicles
|
| Control of robots: presently through hand manipulators; working on implanting chips in brain so that simply thinking of
action activates robot to perform it (thoughts-into-action program or brain-machine interface)
|
| Anesthesia: speakers’ view—within decade, anesthesia no longer used; will be replaced by hibernation or suspended
animation (no risk for death, no pain, no bleeding)
|
| Surgical simulation and training: better training practices, higher-fidelity images, and portable systems; able to
move from subjective analysis to objective analysis; can quantitatively measure ability of person to perform procedure; in
future—residents required to reach benchmark criteria before operating on patients; surgical simulator can be part of
surgical procedure by recording actions and continuously assessing them; can also add “intelligent” tutors, with experts
setting criteria and providing advice when error made; digital libraries will make it possible to perform multiple variations
of procedure and to import information into surgical rehearsal
|
| POSTOPERATIVE ANALGESIA —Daniel H. Burkhardt, MD, Assistant Professor, Department of Anesthesia and Preoperative
Care, and Medical Director, Inpatient Pain Services, University of California, San Francisco, School of Medicine
|
| Assessment of pain: pain fifth vital sign; pain scores highly variable; individual numbers meaningless, only trends useful;
better to look at pain with movement and functional outcomes (eg, ambulation, return of bowel function, readiness
for discharge); even better if mortality benefit present
|
| Opioids: long history of safety and efficacy; side effects can be anticipated (eg, constipation, somnolence, urinary retention);
new or novel pain therapies may have toxicities and not clearly benefit patient; side-effect spectrum (can move up
and down spectrum by adjusting dose of opiate or giving opiate antagonist); also depends on how much pain stimulus
present
|
| General principles of acute pain management: if patient in pain and has no opioid side effects, increase opioid
dose; if patient has opioid side effects and little pain, decrease dose (does not apply to chronic nonmalignant back pain;
when patients have pain and opioid side effects, change opioid or add nonopioid adjuncts (eg, acetaminophen, nonsteroidal
anti-inflammatory drugs [NSAIDs]); with adjuncts, can reduce pain level and improve functional outcome if opioid titration
not adequate
|
| Rational titration of opioids for acute surgical pain: nonopioid adjuncts given round the clock (RTC); short-acting
opioid administered on prn basis so nurse or patient can adjust opioid dose to match pain stimulus; with acute surgical
pain fluctuation, short-acting agent used to catch up rapidly if sudden pain crisis occurs and to disappear when pain relieved;
use long-acting opioid only if using short-acting opioid regularly; if possible, use oral opioids (superior to intravenous
[IV] opioids in every way, except for 20- to 30-min advantage in speed of onset)
|
| IV opioid patient-controlled analgesia (PCA) for acute pain: better patient satisfaction and more convenient
for staff; administration tips—make dose-per-injection large enough to make difference; keep lockout interval short
(speaker typically uses 6-min lockout); smaller dose at shorter interval allows patient to titrate dose more precisely to
pain level; do not use basal rate for acute pain; if patient has acute pain crisis, give bigger bolus; add basal rate for maintenance
of analgesia
|
| IV opioid choices: preferrable to use whichever agent most familiar to staff; hydromorphone (Dilaudid)—long-acting
metabolites; used in renal failure; observed (but not proven) association with delirium in elderly; fentanyl—better side-effect
profile; faster onset and offset (reasonable alternative for PCA)
|
| Long-acting opioids: 4 choices, but most familiar one best; oxycodone—easy to calculate dose; cannot be given
through feeding tube or IV; fentanyl transdermal system (patch)—12-hr onset; expensive (generic available this year);
methadone—takes 24 to 72 hr to take effect; takes several days to reach new steady state after dose increase; PCA
patch—basically same as fentanyl PCA set to 40 µg per injection, 10-min lockout, and no basal rate
|
| Nonopioid adjuncts: acetaminophen, NSAIDs, local anesthetics, and “exotics”; all have toxicities but all reliably reduce
opioid consumption by 20% to 40% in acute pain models; used when opioid already titrated to pain level, but side
effects present before pain relieved; Food and Drug Administration (FDA)—issued warning about thrombotic complications
for all NSAIDs and cyclooxygenase-2 (COX-2) agents; complications true for some but not all NSAIDs; speaker
recommends naproxen (fewer thrombotic complications and slightly protective effect, similar to aspirin)
|
| Epidural local anesthetic: “king” of nonopioid adjuncts; provides band of analgesia centered around dermatome in
which inserted; side effects include numbness, weakness, and hypotension (opioid side effects include itching, urinary retention,
respiratory depression, and ileus); opioid side effects dramatically less than with systemic opioids, except for itching;
urinary retention still fairly common with lumbar epidural (Foley catheterization not necessary with thoracic
epidural); epidurals do not cover opioid addiction and withdrawal, sources of pain outside dermatomal band, eg, nasogastric
tube, and some visceral pains (eg, peritonitis); can remain as long as necessary; catheter infection rare; only reason to
remove before discharge is if patient does not want to care for it at home or to prove that patient comfortable on oral opioids;
does not increase pain when removed (actually reduces pain and may reduce long-term pain); complication rate
0.03%; severe complications include paralysis and epidural hematoma requiring surgery; meta-analysis—neuraxial
blockade for major surgery reduces mortality by slightly >20%, myocardial infarctions by ≈30%, and pneumonia by
≈40%; in appendectomy in young healthy patient, perioperative mortality so low that epidural not worth it (at least from
mortality point of view)
|
| PERIOPERATIVE NUTRITIONAL INTERVENTIONS —Lygia Stewart, MD, Associate Clinical Professor of Surgery,
University of California, San Francisco, School of Medicine, and San Francisco Veterans Affairs Medical Center
|
| Nutritional status: difficult to quantitate completely; patient with 10% weight loss malnourished; with 50% weight
loss, decreased immune function documented; low albumin correlates directly with increased morbidity; albumin decreased
in inflammatory disorders, so difficult to use as measure; prealbumin better predictor and increases more reliably
as patient given nutrition
|
| NPO after midnight: American Society of Anesthesiologists task force on npo recommendations; need only 2-hr fasting
period for clear liquids (emptied rapidly) and 6-hr fasting for light solids low in fat, and 8 hr if upper gastrointestinal (GI)
obstruction with hiatal hernia present; consequences of individual npo after midnight (12-16 hr of fasting)—glycogen
stores depleted; in critically ill patients, insulin resistance correlates directly with mortality; increased free fatty acids (in
catabolic state); research shows postoperative state dictated directly by preoperative state; preoperative oral carbohydrate
drink—specially formulated so that gastric emptying same as with water; prospective randomized studies found decreased
insulin resistance (30%-60%), preservation of immunocompetence, improved well-being, less nausea, less pain,
reduced hospital stay (1-2 days), preservation of skeletal muscle mass, earlier return of muscle strength postoperatively,
and maintenance of muscle glycogen synthetase
|
| Total parenteral nutrition (TPN): associated with increased hyperglycemia, which directly impairs polymorphonuclear
leukocyte (PMN) function; proven to cause proliferation of tumor cells; direct alteration of cytokine production; induces
higher levels of tumor necrosis factor (TNF) and interleukin-6 in response to endotoxin; elevates free radicals;
causes increased IV line infections and costs more; meta-analysis of preoperative TPN—data show ≈10% risk reduction
in malnourished patients; meta-analysis of postoperative TPN—data show 10% increase in morbidity;
conclusion—electively giving TPN worse than giving nothing
|
| Enteral nutrition: keeps mucosal integrity intact; prevents bacterial translocation; studies show enteral feeding better
than standard nutrition (better than TPN); subgroup analysis— tube feeding still better than TPN in all patients; for standard
care, enteral feeding should be used in those with protein-energy malnutrition; postoperative enteral nutrition compared
to no feeding—meta-analysis shows decreased infections of any type when using enteral nutrition
postoperatively; preoperative nutrition (vs none)—study of malnourished patients; decreased overall infection rate and
mortality; length of stay decreased; nutrition more effective preoperatively than postoperatively
|
| Immunonutrition: formulas enhanced with substances thought to be immune enhancing (eg, glutamine, arginine, fish
oil); studies show surgical patients fared much better on immunoformula than with standard enteric formula (with decreased
incidence of infectious complications); also found length of stay decreased in surgical patients, compared to critically
ill patients
|
| Other diets: study of 35 coronary artery bypass graft (CABG) patients on low-glycemic index diet (4 wk); suppression of
nonesterified fatty acids, better glucose uptake in adipocytes, and significant decrease in length of stay
|
| Complications of tube feedings: case reports of intestinal necrosis associated with early use of fiber-containing formulas
and in patients who had some episodes of hypertension; key to stop tube feeding when abdominal distention occurs
and restart only when distention resolved
|
| Pearls: malnourished patients should receive preoperative nutritional support for 7 days; preoperative enteral nutrition for 5
days may be as effective as perioperative and postoperative nutrition; clear liquids should be allowed up to 3 hr preoperatively
in cases without obstruction or gastroesophageal reflux disease (GERD); if oral intake delayed for any reason up to
9 days, should insert feeding tube (superior to TPN); immunonutrition has clear benefits (decreased cost and length of stay)
in surgical patients
|
Educational Objectives
| The goal of this program is to educate the listener about new technologies in robotics and simulation, postoperative
analgesia, and perioperative nutritional interventions. After hearing and assimilating this program, the clinician will
be better able to:
|
 | 1. Discuss why information is critical to surgical innovation.
|
| 2. Describe the operating room of the future.
|
| 3. Apply the general principles of acute pain management.
|
| 4. Determine the appropriate opioid choice.
|
| 5. Evaluate the pros and cons of different perioperative nutritional interventions.
|
Suggested Reading
Adami C: Computer science. What do robots dream of?. Science 314:1093, 2006; Barrett AR et al: Preoperative
planning and intraoperative guidance for accurate computer-assisted minimally invasive hip resurfacing surgery.
Proc Inst Mech Eng [H] 220:759, 2006; Belard JL: Meeting medical challenges in a changing world: the international
program of the U.S. Army Telemedicine and Advanced Technology Research Center (TATRC). Telemed J E
Health 12:426, 2006; Belkhouche F et al: Line of sight robot navigation toward a moving goal. IEEE Trans Syst
Man Cybern B Cybern 36:255, 2006; Belkhouche F et al: Modeling and controlling a robotic convoy using guidance
laws strategies. IEEE Trans Syst Man Cybern B Cybern 35:813, 2005; Bongard J et al: Resilient machines
through continuous self-modeling. Science 314:1118, 2006; Buscarino A et al: Dynamical network interactions in
distributed control of robots. Chaos 16:015116, 2006; Chaitanya VS: Full-state tracking control of a mobile robot
using neural networks. Int J Neural Syst 15:403, 2005; Halvorsen FH et al: Virtual reality simulator training
equals mechanical robotic training in improving robot-assisted basic suturing skills. Surg Endosc 20:1565, 2006;
Heslin MJ, Brennan MF: Advances in perioperative nutrition: cancer. World J Surg. 2000 Dec;24(12):1477-85.
Review; Hollander KW et al: An efficient robotic tendon for gait assistance. J Biomech Eng 128:788, 2006; Nutrition
. 1997 Nov-Dec;13(11-12):996-8; Jude DC et al: Simulation training in the obstetrics and gynecology clerkship.
Am J Obstet Gynecol 195:1489, 2006; Epub 2006 Jul 17; Karaaslan D et al: Comparison of buccal and
intramuscular dexmedetomidine premedication for arthroscopic knee surgery. J Clin Anesth 18:589, 2006; Kim KJ
et al: A comprehensive overview of the applications of artificial life. Artif Life 12:153, 2006 ; Review. Koch S:
Meeting the challenges--the role of medical informatics in an ageing society. Stud Health Technol Inform 124:25,
2006; Kuchenbecker KJ et al: Improving contact realism through event-based haptic feedback. IEEE Trans Vis
Comput Graph 12:219, 2006; Laguna MP et al: Training in laparoscopic urology. Curr Opin Urol 16:65, 2006;
Morita A et al: Microsurgical robotic system for the deep surgical field: development of a prototype and feasibility
studies in animal and cadaveric models. J Neurosurg 103:320, 2005; Muggleton SH: 2020 computing: exceeding
human limits. Nature 440:409, 2006; Rassweiler et al: Robotics and telesurgery—an update on their position in
laparoscopic radical prostatectomy. Minim Invasive Ther Allied Technol 14:109, 2005; Rubin GJ, Hotopf M. Systematic
review and meta-analysis of interventions for postoperative fatigue. Br J Surg. 2002 Aug;89(8):971-84. Review;
Tablov B et al: Fentanyl HCl patient-controlled iontophoretic transdermal system for the management of
acute postoperative pain. Ann Pharmacother 40:2178, 2006; Wang CY et al: Dynamic motion planning for the design
of robotic gait rehabilitation. J Biomech Eng 127:672, 2005; Wang X et al: Improved postoperative analgesia
with coadministration of preoperative epidural ketamine and midazolam. J Clin Anesth 18:563, 2006; Wu CL et al:
Correlation of postoperative epidural analgesia on morbidity and mortality after colectomy in Medicare patients. J
Clin Anesth 18:594, 2006
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue,
the faculty reported nothing to disclose.
Editor’s Note: Dr. Satava’s lecture is the opinion of the author and does not reflect the views of the United States
Department of Defense. Also, his research was federally funded, and the contents therein are considered public domain.
Drs. Satava, Burkhardt, and Stewart were recorded March 23-25, 2006, at the Postgraduate Course in General Surgery
, in San Francisco, CA, and sponsored by the University of California, San Francisco, School of Medicine. The
Audio-Digest Foundation thanks the speakers and the sponsor for their cooperation in the production of this program.
|
