Myths about Perioperative Hypothermia Victoria M. Steelman, PhD, RN, CNOR, FAAN April 28, 2017 APIC Conference Chicago, IL
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Objectives Identify common myths about perioperative hypothermia; Describe the pathophysiology of perioperative hypothermia Identify evidence-based practices for prevention of perioperative hypothermia 3
Disclosures 3M Dr. Steelman is a paid consultant VitaHEAT The University of Iowa has received grant funding Dr. Steelman is a paid consultant 4
Perioperative Hypothermia Compelling evidence identifies what interventions are needed to prevent perioperative hypothermia. This evidence is inadequately infused into clinical practice. Myths or erroneous beliefs are common. Debunking these myths is necessary to provide excellent patient care and improve patient outcomes. This is the next frontier for perioperative patient safety. 5
Myth # 1. Perioperative hypothermia is not a significant issue. Rationale: I haven t seen a problem. No one has told me there has been a problem. We use therapeutic hypothermia for cardiac surgery. 6
Incidence of Perioperative Hypothermia 50-80% of all surgical patients Hypothermia Normothermia 7 Frank SM, ShirY, Raja SN, Fleisher LA, Beattie C. Core hypothermia and skin-surface temperature gradients: epidural versus general anesthesia Galvão CM, Marck PB, Sawada NO, Clark AM. A systematic review of the effectiveness of cutaneous warming systems to prevent hypothermia.j Clin Nurs. 2009;18(5):627-636. Dhar P. Managing perioperative hypothermia. J Anesth. 2000;14(2): 91-97. Fisher, RL. Perioperative hypothermia; Incidence and prevention. Thesis, Columbia University, 1990.
Surgical Site Infection Vasoconstriction Decreased oxygen in tissue Decreased neutrophil activity Decreased deposition of collagen Decreased immune function. Percent of Patients with Surgical site Infection 20% 15% 10% 5% 6% 19% 0% Normthermic Hypothermic Kurz A, Sessler DI, Lenhardt R. N Engl J Med. 1996;334:1209-1215. 8 2015 The University of Iowa. Used with permission.
Myocardial Events 10.0% Percent of Patients with Morbid Cardiac Events Thermoregulatory responses effect cold stress on the cardiovascular system Increases the risk of morbid cardiac event and ventricular tachycardia 8.0% 6.0% 4.0% 2.0% 0.0% 1.4% 6.3% Cardiac Events Normothermic 7.9% 2.4% V Tach Hypothermic 9 2015 The University of Iowa. Used with permission. Frank SM, Fleisher LA, Breslow MJ, et al. JAMA. 1997;277:1127-1134.
Blood Loss Platelet function & coagulation cascade are impaired Increased blood loss 2500 2000 1500 1000 500 0 Average Blood Loss (ml) 2200 1700 618 488 Study 1 Study 2 Normothermic Hypothermic 1. Winkler M, Akca O, Birkenberg B, et al. Anesth Analg. 2000;91:978-984. 2. Schmied H, Kurz A, Sessler DI, Kozek S, Reiter A. Lancet. 1996;347:289-292; 10 2015 The University of Iowa. Used with permission.
Drug Metabolism Hypothermia reduces drug metabolism More than doubles the duration of action of neuromuscular blocking agents Increased length of stay in postanesthesia recovery 100 90 80 70 60 50 40 30 20 10 0 Length of Postanesthesia Stay (min) 53 Normthermic 94 Hypothermic Lenhardt R, Marker E, Goll V, et al. Anesthesiology. 1997;87:1318-1323. 11 2015 The University of Iowa. Used with permission.
Myth # 2. Increasing the ambient temperature of the operating room will prevent perioperative hypothermia. Rationale: It s just logical. At home, if we get cold, we turn up the room temperature. 12
How does Hypothermia Happen? General Anesthesia Removes ability to employ behavioral responses Widens the interthreshold range 20-fold (0.2 o C to 4 o C) Diminishes the hypothalmic response Regional Anesthesia Response is similar to general anesthesia Prevents normal activation of regional responses (sweating, shivering) Impairs central control of thermoregulation Incorrectly judges skin temperature Patients often feel warm when they are not Interthreshold range is increased by 0.6 o C 13 Sessler DI. Perioperative thermoregulation and heat balance. Lancet. 2016;387(10038):2655-2664.
Heat Loss Heat is lost into the cool operating room environment Large areas of skin often exposed during prepping and draping Internal organs often exposed during surgery Cool intravenous or irrigation fluids increase heat loss 14
Redistribution Hypothermia Most patients undergoing surgery experience hypothermia unless effective prevention is used. Redistribution of heat from core to periphery occurs upon induction of general anesthesia/administration of a spinal anesthesia. Occurs in patients undergoing surgery >30 minutes duration. 15
Ineffective Prevention Increasing the room temperature in the OR Normal Core Temperature Room Temperature Gradient 98.6 o F 70 o F 28.6 o F 98.6 o F 75 o F 23.6 o F 98.6 o F 80 o F 18.6 o F 98.6 o F 85 o F 13.6 o F 16
Active Warming Is Needed Active warming is required to prevent perioperative hypothermia. Peripheral tissues are heated, decreasing the temperature gradient between the core and periphery. Types of Active Warming: Forced-air warming Radiant warming Circulating water garment Energy transfer pads Carbon fiber resistive technology Silver/carbon ink resistive technology Warmed IV fluids when >1 liter administered Adjunct; alone does not prevent hypothermia 17
Myth # 3. Turning on the forced air warming after anesthesia start is effective prevention. Rationale: I need to turn on the compression stockings before anesthesia starts, and I don t have time to do both. Documentation does not indicate when I turned it on. 18
Preoperative Warming Active warming is more effective when patients are warmed 30 minutes before surgery. 1-4 AORN Guideline 5 ASPAN Guideline 6 19 1. Andrzejowski J, et al. Br. J. Anaesth. 2008;101(5):627-631. 2. Horn EP, et al. Anesth. Analg. 2002;94(2):409-414. 4. Vanni SM, et al. J Clin Anesth. 2003;15(2):119-125. 4. Horn EP, et al. Eur. J. Anaesthesiol. 2016; 33:334-340. 5. Guideline for prevention of unplanned patient hypothermia. AORN, 2017. 6. Hooper VD, et al. Journal of Perianesthesia Nursing, 2010;25(6):346-365.
Myth # 4. Cotton blankets are adequate for preoperative warming. Rationale: Blankets feel good. Patients like them. Our documentation system includes this in the menu of interventions for prevention of hypothermia. It is less expensive than forced air warming. 20
Ineffective Prevention Passive warming retains heat only Cotton blankets Reduce heat loss by only 33% in non-anesthetized persons 1 Heated cotton blankets Effect lasts 10 minutes 1 In an RCT, resulted in core temperature of 35.5 o C 2 Reflective blankets 3 21 1. Sessler DI, Schroeder M. Anesth. Analg. 1993;77(1):73-77. 2. Fossum S, Hays J, Henson MM. Journal of Perianesthesia Nursing. 2001;16(3):187-194. 3. Ng et al. Anesth. Analg. 2003;96(1):171-176.
Cost of Using Warmed Cotton Blankets Supply/Labor Cost per Patient Laundering blankets $10.80 Labor: Nursing assistant stocking blankets (1.5 minutes) $ 0.30 Labor: RN applying cotton blankets (2 minutes/blanket) $ 6.60 Total cost supplies and labor $17.70 $17.70 per patient for an ineffective method of prevention of hypothermia. 22
Myth # 5. Warming intraperitoneal gases during laparoscopy is an effective intervention for preventing hypothermia. Rationale: It is logical. Most of our patients are laparoscopic and this is an easy intervention. Surgeon X wants this. It prevents lens fogging. 23
Heated CO 2 is Ineffective Heated CO 2 with or without humidification for minimally invasive abdominal surgery. 16 eligible studies for meta-analysis Heated gases with or without humidification Birch DW, Manouchehri N, Shi X, Hadi G, Karmali S. Cochrane Database Syst Rev. 2011 Jan 19;(1):CD007821. Results- No effect on: Core temperature Pain Morphine consumption LOS LOS in PACU Lens fogging Ineffective and costly. 24
Potential Cost Avoidance: CO(2) Insufflation Tubing # Laparoscopies Cost of tubing Weekly Cost Annual Cost Savings 50/wk $37 $1,850 $96,200 100/wk $37 $3,700 $192,400 25
Myth # 6. Compliance with the quality performance indicator means we are providing excellent patient care. Rationale: That is why they make quality performance indicators. It is evidence-based. Administration is happy with our results. 26
Quality Performance Measure Perioperative Temperature Management Written by the AMA Physician Consortium for Process Improvement (PCPI) Anesthesia and Critical Care Workgroup Endorsed by the National Quality Forum (NQF) 23 Used by The Joint Commission, Centers for Medicare and Medicaid Services 27
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Quality Performance Measure Process measure No evaluation of fidelity Compliance can be achieved without appropriately using active warming or achieving normothermia Inspires checklist mentality and complacency 29
The Gap The Gap between Compliance with the Quality Performance Measure "Perioperative Temperature Management" and Normothermia. Steelman VM, Perkhounkova YS, Lemke JH. J Healthc Qual. 2015 Nov-Dec;37(6):333-41. doi: 10.1111/jhq.12063. 5.8% of patients for whom the quality performance measure was met were hypothermic upon admission PACU. 30 30
Data Are Needed Preoperative warming adherence Preop area Later: ED, inpatient units Intraoperative warming adherence % use of active warming technology % started before induction of anesthesia Percent patients who are hypothermic =/> 30 minutes surgery duration Stratified by surgical service Later: Stratified by problem-prone areas 31
Summary Myths about perioperative hypothermia are a barrier to achieving full adoption of evidence-based practices and optimal patient outcomes. Understanding the pathophysiology of perioperative hypothermia is essential. Active warming preoperatively and intraoperatively is essential. Education is never enough. Measure patient outcomes, not quality performance measures. 32
33 Your Questions
References Andrzejowski J, Hoyle J, Eapen G, Turnbull D. Effect of prewarming on post-induction core temperature and the incidence of inadvertent perioperative hypothermia in patients undergoing general anaesthesia. Br. J. Anaesth. 2008;101(5):627-631. Andrzejowski JC, Turnbull D, Nandakumar A, Gowthaman S, Eapen G. A randomised single blinded study of the administration of pre-warmed fluid vs active fluid warming on the incidence of perioperative hypothermia in short surgical procedures. Anaesthesia. 2010;65(9):942-945. Birch DW, Manouchehri N, Shi X, Hadi G, Karmali S. Heated CO(2) with or without humidification for minimally invasive abdominal surgery. Cochrane database of systematic reviews (Online). 2011;(1)(1):CD007821. Dhar P. Managing perioperative hypothermia. J. Anesth. 2000;14(2):91-97. Fossum S, Hays J, Henson MM. A comparison study on the effects of prewarming patients in the outpatient surgery setting. J. Perianesth. Nurs. 2001;16(3):187-194. Frank SM, Fleisher LA, Breslow MJ, et al. Perioperative maintenance of normothermia reduces the incidence of morbid cardiac events. A randomized clinical trial. JAMA. 1997;277(14):1127-1134. Frank SM, ShirY, Raja SN, Fleisher LA, Beattie C. Core hypothermia and skin-surface temperature gradients. Epidural versus general anesthesia and the effects of age. Anesthesiology. 1994;80(3):502-508. Galvao CM, Marck PB, Sawada NO, Clark AM. A systematic review of the effectiveness of cutaneous warming systems to prevent hypothermia. J. Clin. Nurs. 2009;18(5):627-636. 34
35 Guideline for prevention of unplanned patient hypothermia. In: AORN, ed. 2017 Guidelines for Perioperative Practice.Vol 2017. Denver, CO: Association of perioperative Registered Nurses; 2017:567-590. Hooper VD, Chard R, Clifford T, et al. ASPAN's evidence-based clinical practice guideline for the promotion of perioperative normothermia: second edition. J. Perianesth. Nurs. 2010;25(6):346-365. Horn EP, Bein B, Broch O, et al. Warming before and after epidural block before general anaesthesia for major abdominal surgery prevents perioperative hypothermia: A randomised controlled trial. Eur. J. Anaesthesiol. 2016;33:334-340. Horn EP, Schroeder F, Gottschalk A, et al. Active warming during cesarean delivery. Anesth. Analg. 2002;94(2):409-414. Kurz A, Sessler DI, Christensen R, Clough D, Plattner O, Xiong J. Thermoregulatory vasoconstriction and perianesthetic heat transfer. ActaanaesthesiologicaScandinavica.Supplementum. 1996;109:30-33. Lenhardt R, Marker E, GollV, et al. Mild intraoperative hypothermia prolongs postanesthetic recovery. Anesthesiology. 1997;87(6):1318-1323. Ng SF, Oo CS, Loh KH, Lim PY, Chan YH, Ong BC. A comparative study of three warming interventions to determine the most effective in maintaining perioperative normothermia. Anesth. Analg. 2003;96(1):171-176. Sessler DI. Perioperative thermoregulation and heat balance. Lancet. 2016;387(10038):2655-2664. Sessler DI, Schroeder M. Heat loss in humans covered with cotton hospital blankets. Anesth. Analg. 1993;77(1):73-77.
Shaw CS, Steelman VM, DeBerg J, Schweizer M. Title:Effectiveness of active and passive warming for the prevention of inadvertent hypothermia in patients receiving neuraxial anesthesia: A systematic review and meta-analysis of randomized controlled trials. J Clin Anesth. 2017. Steelman VM, Perkhounkova YS, Lemke JH. The Gap between Compliance with the Quality Performance Measure "Perioperative Temperature Management" and Normothermia. J Healthc Qual. 2015;37(6):333-341. Vanni SM, Braz JR, Modolo NS, Amorim RB, Rodrigues GR, Jr. Preoperative combined with intraoperative skin-surface warming avoids hypothermia caused by general anesthesia and surgery. J Clin Anesth. 2003;15(2):119-125. 36