Operating Room Fires.

Operating room fires are rare but devastating events. Guidelines are available for the prevention and management of surgical fires; however, these recommendations are based on expert opinion and case series. The three components of an operating room fire are present in virtually all surgical procedures: an oxidizer (oxygen, nitrous oxide), an ignition source (i.e., laser, "Bovie"), and a fuel. This review analyzes each fire ingredient to determine the optimal clinical strategy to reduce the risk of fire. Surgical checklists, team training, and the specific management of an operating room fire are also reviewed.

Operating Room Management at the Edge of Order and Chaos.

The operating room (OR) management literature tends to view management problems as having finite solutions and assumes that equilibrium exists in the intricate encounters that occur every day. In this article, we review complexity theory and assess its applicability to the strategic, tactical, and operational issues facing OR managers. By building on complexity theory and its assumptions, we also show that as complex systems, ORs resemble high-reliability organizations more than they resemble ultra-safe organizations. This distinction and the limitations of the current, linear modeling may have potential implications for the future of OR management research and practice. Opening the door to complexity, understanding the underpinnings of high-reliability organizations, and admitting that OR systems are complex adaptive systems, will lead to self-governing, transparent processes that envision the OR as a living, growing, sustainable human endeavor.

Cognitive outcome after spinal anesthesia and surgery during infancy.

BACKGROUND: Observational studies on pediatric anesthesia neurotoxicity have been unable to distinguish long-term effects of general anesthesia (GA) from factors associated with the need for surgery. A recent study on elementary school children who had received a single GA during the first year of life demonstrated an association in otherwise healthy children between the duration of anesthesia and diminished test scores and also revealed a subgroup of children with "very poor academic achievement" (VPAA), scoring below the fifth percentile on standardized testing. Analysis of postoperative cognitive function in a similar cohort of children anesthetized with an alternative to GA may help to begin to separate the effects of anesthesia from other confounders. METHODS: We used a novel methodology to construct a combined medical and educational database to search for these effects in a similar cohort of children receiving spinal anesthesia (SA) for the same procedures. We compared former patients with a control population of students matched by grade, gender, year of testing, and socioeconomic status. RESULTS: Vermont Department of Education records were analyzed for 265 students who had a single exposure to SA during infancy for circumcision, pyloromyotomy, or inguinal hernia repair. Exposure to SA and surgery had no significant effect on the odds of children having VPAA. (mathematics: P = 0.18; odds ratio 1.50, confidence interval (CI), 0.83-2.68; reading: P = 0.55; odds ratio = 1.19, CI, 0.67-2.1). There was no relationship between duration of exposure to SA and surgery and performance on mathematics (P = 0.73) or reading (P = 0.57) standardized testing. There was a small but statistically significant decrease in reading and math scores in the exposed group (mathematics: P = 0.03; reading: P = 0.02). CONCLUSIONS: We found no link between duration of surgery with infant SA and scores on academic achievement testing in elementary school. We also found no relationship between infant SA and surgery with VPAA on elementary school testing, although the CIs were wide.

Pain management in current combat operations.

Pain management in the U.S. Military, particularly in combat, shares many of the same principles found in civilian heath care organizations and institutions. Pain is one of the most common reasons for which soldiers seek medical attention in the combat environment, which mirrors the civilian experience. However, the combat environment exacerbates the typical challenges found in treating acute pain and has the additional obstacles of a lack of supplies and equipment, delayed or prolonged evacuation times and distances, devastating injuries, provider inexperience, and dangerous tactical situations. These factors contribute to the difficulty in controlling a soldier's pain in combat. Furthermore, civilian health care providers have also learned the importance of practicing pain management principles in austere and tactical environments because of recent natural and man-made domestic disasters. Pain management research, education, and treatment strategies have been created to try to achieve adequate battlefield analgesia, and these lessons learned may aid civilian health care providers if the circumstances arise. This article presents a brief history and current overview of pain management for combat casualties on today's battlefield. Recent natural disasters and increased threats for terrorist acts have proven the need for civilian health care providers to be properly trained in pain management principles in an austere or tactical environment.

The relationship of intravenous midazolam and posttraumatic stress disorder development in burned soldiers.

BACKGROUND: Midazolam, a short-acting benzodiazepine, is administered preoperatively and intraoperatively for amnesia and anxiolysis. Subsequently, patients often do not recall events which occurred while they were sedated. Recent studies have also reported retrograde facilitation after midazolam exposure. Posttraumatic stress disorder PTSD is based on memory of a traumatic event. Because of the concern that midazolam may enhance memory of the traumatic event in which soldiers were injured, we investigated the prevalence of PTSD in those burned soldiers who received perioperative midazolam and those who did not. We also investigated the intensity of the memories related to the traumatic event. METHODS: After institutional review board approval, all charts of US soldiers who completed the PTSD Checklist-Military (PCL-M) screening tool (2004-2008) after admission to US Army Institute of Surgical Research were reviewed to determine the number of operations, the anesthetic regime, total body surface area (TBSA) burned, and Injury Severity Score (ISS). RESULTS: The PCL-M was completed by 370 burned soldiers from Operation Iraqi Freedom/Operation Enduring Freedom. During surgery, 142 received midazolam, whereas 69 did not. The prevalence of PTSD was higher in soldiers receiving midazolam as compared with those who did not (29% vs. 25%) (p = 0.481). Both groups had similar injuries based on TBSA and ISS. Patients who received midazolam also had similar scores on PCL-M questions related to memory of the event. CONCLUSIONS: Rates of PTSD are not statistically different in combat casualties receiving midazolam during intraoperative procedures. Intraoperative midazolam is not associated with increased PTSD development or with increased intensity of memory of the traumatic event. Patients receiving midazolam had similar injuries (TBSA and ISS) and underwent a similar number of operations as those not receiving midazolam.

The evolution of pain management in the critically ill trauma patient: Emerging concepts from the global war on terrorism.

BACKGROUND: The evolution of military medical care to manage polytrauma, critically ill-wounded warriors from the greater war on terrorism has been accompanied by significant changes in the diagnosis, management, and modulation of acute and chronic trauma-related pain. A paradigm shift in pain management includes early treatment of pain at the point of injury and throughout the continuum of care with a combination of standard and novel therapeutic interventions. These concepts are important for all critical care providers because they translate to most critically ill patients, including those resulting from natural disasters. Previous authors have reported a high incidence of moderate to severe pain and poor analgesia in intensive care units associated with sleep disturbances, tachycardia, pulmonary complications, increased stress response with thromboembolic incidents, and immunosuppression, increased intensive care unit and hospital stays, and needless suffering. Although opioids have traditionally been the cornerstone of acute pain management, they have potential negative effects ranging from sedation, confusion, respiratory depression, nausea, ileus, constipation, tolerance, opioid-induced hyperalgesia as well as potential for immunosuppression. Alternatively, multimodal therapy is increasingly recognized as a critical pain management approach, especially when combined with early nutrition and ambulation, designed to improve functional recovery and decrease chronic pain conditions. DISCUSSION: Multimodal therapy encompasses a wide range of procedures and medications, including regional analgesia with continuous epidural or peripheral nerve block infusions, judicious opioids, acetaminophen, anti-inflammatory agents, anticonvulsants, ketamine, clonidine, mexiletine, antidepressants, and anxiolytics as options to treat or modulate pain at various sites of action. SUMMARY: With a more aggressive acute pain management strategy, the military has decreased acute and chronic pain conditions, which may have application in the civilian sector as well.

Total intravenous anesthesia including ketamine versus volatile gas anesthesia for combat-related operative traumatic brain injury.

BACKGROUND: Traumatic brain injury is a leading cause of death and severe neurologic disability. The effect of anesthesia techniques on neurologic outcomes in traumatic brain injury and potential benefits of total intravenous anesthesia (TIVA) compared with volatile gas anesthesia (VGA), although proposed, has not been well evaluated. The purpose of this study was to compare TIVA versus VGA in patients with combat-related traumatic brain injury. METHODS: The authors retrospectively reviewed 252 patients who had traumatic brain injury and underwent operative neurosurgical intervention. Statistical analyses, including propensity score and matched analyses, were performed to assess differences between treatment groups (TIVA vs. VGA) and good neurologic outcome. RESULTS: Two hundred fourteen patients met inclusion criteria and were analyzed; 120 received VGA and 94 received TIVA. Good neurologic outcome (Glasgow Outcome Score 4-5) and decreased mortality were associated with TIVA compared with VGA (75% vs. 54%; P = 0.002 and 5% vs. 16%; P = 0.02, respectively). Multivariate logistic regression found admission Glasgow Coma Scale score of 8 or greater (odds ratio, 13.3; P < 0.001) and TIVA use (odds ratio, 2.3; P = 0.05) to be associated with good neurologic outcomes. After controlling for confounding factors using propensity analysis and repeated one-to-one matching of patients receiving TIVA with those receiving VGA with regard to Injury Severity Score, Glasgow Coma Scale score, base deficit, Head Abbreviated Injury Score, and craniectomy or craniotomy, the authors could not find an association between treatment and neurologic outcome. CONCLUSION: Total intravenous anesthesia often including ketamine was not associated with improved neurologic outcome compared with VGA. Multiple confounders limit conclusions that can be drawn from this retrospective study.

Novel use of a portable ventilation device with low-flow tracheal insufflation of oxygen in a Swine model.

INTRODUCTION: Mechanical ventilation of intubated patients is standard to meet oxygenation and ventilation goals. This can require significant energy and oxygen resources. In military operations and mass casualty disasters, oxygen conserving strategies may be important. Low flow tracheal insufflation of oxygen (TRIO) is a technique that provides adequate oxygenation while conserving oxygen during apnea. This technique, however, is limited by increases in carbon dioxide (CO2) when used for extended periods. The addition of passive pressure release ventilation could potentially improve CO2 elimination and the acceptance of this technique. The purpose of this study was to determine whether TRIO combined with the novel configuration of a portable ventilator used to provide passive pressure release ventilation improves CO2 levels during apneic oxygenation. METHODS: Animals (n = 7) were anesthetized, paralyzed, and intubated. Oxygen (O2) was insufflated through the capillary lumen of the Boussignac endotracheal tube at 2 L/min. The low flow O2 was the only source of power and gas for ventilation. A modified Oxylator EMX transport ventilator connected to the endotracheal tube was configured to release when pressure in the subjects lungs reached 30 cm H2O. No electrical or pneumatic sources were required. Hemodynamic measurements and arterial blood gases were taken at various intervals for 2 hours. RESULTS: All pigs remained adequately oxygenated with Pao2 >390 mm Hg in all subjects at every blood gas measurement and survived the 2-hour experiment. Baseline Paco2 (43 +/- 4 mm Hg) increased and pH (7.48 +/- 0.03) decreased to 72 +/- 5 mm Hg and 7.29 +/- 0.02 at 1 hour and 83 +/- 8, 7.24 +/- 0.03 at 2 hours. This is significantly less than would be expected during apnea over this time period. Hemodynamic measurements remained stable. CONCLUSION: The combination of low flow TRIO with a modified Oxylator in this novel configuration provides acceptable Pao2, Paco2, and hemodynamic parameters for 2 hours in apneic swine. This could be a valuable technique in situations where oxygen and power are limited.

The correlation between ketamine and posttraumatic stress disorder in burned service members.

BACKGROUND: Predisposing factors for posttraumatic stress disorder (PTSD) include experiencing a traumatic event, threat of injury or death, and untreated pain. Ketamine, an anesthetic, is used at low doses as part of a multimodal anesthetic regimen. However, since ketamine is associated with psychosomatic effects, there is a concern that ketamine may increase the risk of developing PTSD. This study investigated the prevalence of PTSD in Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) service members who were treated for burns in a military treatment center. METHODS: The PTSD Checklist-Military (PCL-M) is a 17-question screening tool for PTSD used by the military. A score of 44 or higher is a positive screen for PTSD. The charts of all OIF/OEF soldiers with burns who completed the PCL-M screening tool (2002-2007) were reviewed to determine the number of surgeries received, the anesthetic regime used, including amounts given, the total body surface area burned, and injury severity score. Morphine equivalent units were calculated using standard dosage conversion factors. RESULTS: The prevalence of PTSD in patients receiving ketamine during their operation(s) was compared with patients not receiving ketamine. Of the 25,000 soldiers injured in OIF/OEF, United States Army Institute of Surgical Research received 603 burned casualties, of which 241 completed the PCL-M. Of those, 147 soldiers underwent at least one operation. Among 119 patients who received ketamine during surgery and 28 who did not; the prevalence of PTSD was 27% (32 of 119) versus 46% (13 of 28), respectively (p = 0.044). CONCLUSIONS: Contrary to expectations, patients receiving perioperative ketamine had a lower prevalence of PTSD than soldiers receiving no ketamine during their surgeries despite having larger burns, higher injury severity score, undergoing more operations, and spending more time in the ICU.

A comparison of target-controlled infusion versus volatile inhalant anesthesia for heart rate, respiratory rate, and recovery time in a rat model.

We conducted this study to determine whether heart rate, respiratory rate, and recovery time differed significantly between rats receiving target-controlled infusion (TCI) and those under volatile inhalant anesthesia. TCI rats received intravenous propofol at an average effect site concentration of 11.3 microg/ml or propofol plus ketamine (5 mg/ml of propofol) at an average effect site concentration of 8.7 microg/ml. Inhalant anesthesia rats received isoflurane (average, 1.8%) delivered in medical-grade air. We used a tail-clamp response test to determine when a surgical plane of anesthesia was attained. Anesthesia was continued for 1 h from the first negative tail-clamp test. During this time the test was repeated every 10 min to confirm that a surgical plane of anesthesia was being maintained. Anesthesia then was discontinued, and the animals were monitored continuously until they recovered. Average heart rate was higher for rats during anesthesia with isoflurane compared with TCI propofol-ketamine (P =0.0053). Average respiratory rate was higher for TCI regimens compared with isoflurane anesthesia, with male rats having consistently faster respiratory rates than females (P <0.001). Recovery time was longer for both TCI regimens compared with isoflurane (P <0.001). Once venous access was accomplished, TCI anesthesia with propofol or propofol combined with a low dose of ketamine was comparable to an isoflurane inhalant regimen in ease of administration and control of the anesthetic event when used in rats for procedures of 1-h duration. Respiratory rate was increased and recovery time was longer for rats receiving the TCI regimens.

Observational study of Mallampati changes after prone spinal surgery.

STUDY OBJECTIVE: To evaluate airway changes in patients undergoing surgery in the prone position. DESIGN: Single-arm observational study. PATIENTS: Patients between 18 to 65 years old, scheduled for prone spinal surgery; 74 patients were enrolled and 54 patients were analyzed. INTERVENTION: The initial airway examination was graded according to the Samsoon and Young modification of the Mallampati classification (MMP). Airway photographs were obtained in a standardized manner and were repeated 20 minutes after extubation. The photographs were then randomized. MEASUREMENTS: Subjects' age, gender, race, weight, duration of surgery, amount of crystalloid fluid given, and estimated blood loss were recorded. Three senior anesthesiologists who were blinded to the origin of the photographs analyzed and graded the airways. MAIN RESULTS: All statistical tests showed significance between pre-MMP and post-MMP scores (P<0.001). There was no difference between pre and post interobserver MMP scores. The MMPs of 12 patients (22%) did not change and MMP scores were changed in 42 patients (78%): 30 (71%) patients by one class, 10 (24%) patients by two classes, and two patients (5%) by three classes. There was no correlation between patients whose MMP was changed and length of surgery or crystalloid administered. CONCLUSION: Modified Mallampati scores increased in the majority of patients after spinal surgery in the prone position.