The complexities of managing severe burns with associated trauma

A high incidence of severe inhalation injuries can be expected in the combined injury patient. The initial management remains attention to the ATLS priorities of airway, breathing, and circulation, with prompt and safe transfer to a regional center of excellence. The treatment of either the burn or the associated injuries may be compromised by their combined presence, and a team approach is essential to their optimal management. Circulatory management goals based on oxygen consumption and delivery allow greater understanding and control of the physiologic demands placed on the patient by the disease process. The management of inhalation injury and ARDS is at an exciting turning point in history, and we now have in hand and use many techniques that allow salvage of these mortal conditions. Pain management is essential to humane care and requires frequent assessment and patient control to be effective. Rehabilitation of the burn and trauma patient starts on the day of injury and requires team dedication to the areas of greatest morbidity early in the planning of surgical priorities and physical therapy.

Shock: ischemia, reperfusion, and inflammation

The pathophysiology of shock after trauma and hemorrhage has traditionally been viewed as a result of ischemic cellular damage. However, it is now clear that ischemia alone does not result in all cellular damage after shock. Rather, much of the cellular injury follows reperfusion and subsequent inflammation. Sublethal ischemia alters (primes) cells. This priming is mediated by second messengers, such as intracellular calcium, cyclic adenosine monophosphate, phosphatidic acids, and reactive oxygen species (ROS). Cells so primed by ischemia are both more susceptible to injury by subsequent reperfusion and inflammation, and may be primed to participate as effectors in the subsequent inflammatory response. Reperfusion of ischemic cells results in an oxygen radical burst. The resulting ROS are both directly cytotoxic and activate transcription factors for new protein synthesis. This activation of transcription factors results in activation of leukocytes, macrophages, and endothelial cells, initiating an inflammatory state which may result in organ failure and death. Monitoring to detect evidence of reperfusion and inflammation will be of value as new therapeutic approaches are developed. Antioxidant therapy has the potential to limit cellular and organ damage from reperfusion and inflammation after shock.

Increasing nitric oxide production improves survival in experimental hemorrhagic shock

The purpose of this study was to evaluate the importance of nitric oxide (NO) upon outcome following hemorrhagic shock. L-Arginine, an NO precursor, and L-NMMA, an inhibitor of NO synthesis, were added to resuscitation in a prospective, randomized, and double-blinded experimental model, and the effects upon blood pressure and survival were measured.

METHODS

60 Sprague-Dawley rats were anesthetized and subjected to phlebotomy to induce hemmorrhagic shock. After a 45 min shock period, animals were resuscitated with either lactated Ringer's alone (control), L-NMMA in lactated Ringer's or L-arginine in lactated Ringer's. Blood pressure was monitored, and animals were observed for survival. As an additional control experiment, 15 additional animals underwent the same protocol, but underwent sham shock, i.e. were not haemorrhaged.

RESULTS

L-NMMA increased blood pressure transiently following sham shock, but increased blood pressure to a greater extent and for a longer duration following hemorrhage. However, L-NMMA had no effect upon survival. L-Arginine had no measurable effect upon blood pressure, but significantly increased survival.

CONCLUSION

NO may play an important role following hemorrhage. The effectiveness of L-NMMA as a pressor suggests that NO contributes to hypotension following hemorrhage. However, reversing hypotension with L-NMMA did not improve survival in this model. In contrast, L-arginine did not further lower blood pressure, but had significant survival benefit. This suggests a possible protective effect of NO after hemorrhage, perhaps by improving the distribution of capillary blood flow and/or by decreasing platelet aggregation and leukocyte adhesion within the microcirculation.

Should Critical Care Medicine be a Formal Part of the Undergraduate Curriculum?

Medical students were surveyed shortly after completing the third year of medical school. The survey was designed to identify those areas of critical care medicine students had been exposed to and expressed interest in learning more about. In addition, the surveys sought to discern the level of confidence students felt with respect to different critical illnesses and intensive care unit (ICU) therapeutic modalities. Finally, the students were asked their opinion regarding the possibility or need for critical care medicine as part of their medical school curriculum. The three most common topics of interest among medical students who had recently finished their third year in medical school were shock, hemodynamic monitoring, and mechanical ventilation. Less than 30% of the students surveyed felt “better-than-average” confidence on any one of a number of critical care topics and treatment modalities. Of the 80% of students (n = 70) who completed the survey, 91% (n = 64) felt that critical care medicine should be made a part of the medical school curriculum, 6% (n = 4) felt it should not, and 3% (n = 2) were undecided. The survey results and the finding that most of the relevant literature acknowledges the need for critical care medicine in medical school has led us to conclude that a national core clerkship or a didactic lecture series in critical care medicine should be carefully designed and implemented into the undergraduate curriculum.

Splenic infarction from cholesterol embolization following cardiopulmonary bypass

The authors report a case of symptomatic splenic infarction secondary to cholesterol embolization after coronary artery bypass grafting in a 59-year-old woman. The patient was treated with urgent splenectomy, which was curative. The diagnosis, investigations and management of the condition are discussed.

Decreasing unplanned extubations in the surgical intensive care unit

BACKGROUND

Unplanned extubations are common, but can be life-threatening.

METHODS

We conducted a prospective evaluation of all intubated patients in our surgical intensive care unit to examine the effects of three parameters on the likelihood of accidental extubation. The parameters were the method of endotracheal tube fixation, the use of sedation/paralysis, and the use of hand restraints. During the baseline period, tubes were secured with cloth or velcro ties, sedation was used conservatively, and hand restraints were used routinely. A change in one study parameter was made prior to each period. Thus, in period II, tubes were secured using waterproof tape; in period III, tubes were secured with waterproof tape and sedation/paralysis was used liberally; and in period IV, tubes were secured with waterproof tape and limited use was made of hand restraints.

RESULTS

Accidental extubations were significantly less frequent when tubes were secured with waterproof tape (P < 0.0001). No difference was seen when sedation was instituted liberally. Restricted use of hand restraints was associated with significantly increased accidental extubations (P < 0.001).

CONCLUSIONS

Our data support the use of water resistant tape to secure endotracheal tubes and the routine use of hand restraints.

The effect of Polyethylene Glycol-Superoxide Dismutase on gastric mucosa and survival in shock with tissue injury

Oxygen-derived free radicals may play an important role in the pathogenesis of organ injury and death following hemorrhagic shock. This study was designed to test the effects of Polyethylene Glycol-Superoxide Dismutase (PEG-SOD) on gastric mucosal injury and survival in an animal model of hemorrhagic shock and tissue trauma. Reproducible tissue trauma was produced by IM injection of turpentine (1.4 microliters/g). A standardized hemorrhagic shock model with an LD 90 was employed. This model consisted of the following sequence of events: phlebotomy to 60 per cent blood volume, 45-minute shock period, resuscitation using Lactated Ringers (LR) at two times shed volume over 60 minutes. Twenty rats were randomly assigned to receive LR (control) or PEG-SOD (5.36 mg/kg). Immediately following the death or at 72 hours, the stomach was removed. Computer image analysis was used to determine the lesion area as a per cent of total gastric mucosal surface area. Our results show no statistical difference in gastric mucosal lesion area between groups (1.83% vs 1.75%, respectively). Survival at 72 hours was significantly higher for PEG-SOD animals vs controls (70% vs 10%, P = 0.0001). This data suggests that IV administration of PEG-SOD during resuscitation is a potentially effective means of improving survival following severe hemorrhagic shock and tissue injury.

Effects of trauma on leukocyte intercellular adhesion molecule-1, CD11b, and CD18 expressions

BACKGROUND

During traumatic injury, a multitude of events, including ischemia, may cause leukocyte adhesion and margination. In this study, alterations of surface receptors involved in leukocyte adhesion were studied in traumatized patients. In an attempt to discern the role of hypoxia, additional experiments were conducted in which normal human leukocytes were subjected to hypoxic stress in vitro.

METHODS

Venous blood was obtained from 10 trauma patients within 2 hours of blunt injury (mean Injury Severity Score of 17 +/- 8) and from 8 normal volunteers (controls). Leukocytes were isolated from patients and controls. To assess the effect of hypoxia, normal leukocytes were placed in hermetically sealed environments containing 100% nitrogen. All leukocytes were labeled with phycoerythrin- or fluorescein-bound monoclonal antibodies to intercellular adhesion molecule-1 (ICAM-1), or to integrins CD18 and CD11b. Receptor concentration was measured by flow cytometry. Results were expressed as percentage of receptor-positive cells (%) and mean fluorescence channel units, which directly correlate with monoclonal antibody cell surface density. Significance of differences was tested by analysis of variance/Kruskal-Wallis test.

RESULTS

Compared with the normal controls, circulating leukocytes obtained from traumatized patients showed decreased expression of ICAM-1, CD11b, and CD18 2 hours after injury. In contrast, normal leukocytes exposed to hypoxic stress in vitro exhibited a marked increase in CD11b and CD18 expression and no change in ICAM-1 expression.

CONCLUSIONS

Leukocytes obtained from traumatized patients showed a significant decrease in cell surface expression of adhesion receptors. This phenomenon is unlikely to be a direct consequence of hypoxia alone, because exposure to isolated hypoxia in vitro actually increased expression of CD11b and CD18.

Ethanol added to resuscitation improves survival in an experimental model of hemorrhagic shock

Ethyl alcohol induces systemic vasodilation, decreases platelet aggregation, and inhibits neutrophil activation in vivo. Alcohol may thus be of potential benefit in resuscitation from shock by improving microcirculation. The purpose of this study was to test the effects of ethanol (ETOH) in resuscitation from hemorrhagic shock. Blood pressure, tissue pO2, white blood cell (WBC) and platelet adhesiveness, and survival were measured for 60 male Sprague-Dawley rats in a blinded and randomized study. Anesthetized animals were phlebotomized to 60 per cent of their blood volume, and maintained in shock for 45 minutes. Resuscitation was by continuous infusion of Lactated Ringers (LR) at 2 x shed blood volume over 1 hour. The experimental group received LR and ETOH (1.25 mL/kg). Control rats received LR and placebo. Mean arterial pressure was not significantly different, nor was WBC adhesiveness index different. However, postresuscitation platelet adhesiveness index was significantly higher in control rats than in ETOH rats. Postresuscitation total platelet arterial-venous difference was also greater in controls than in ETOH rats. Average tissue pO2 for ETOH rats (47 +/- 8.2 mm Hg) was significantly higher than controls (39.0 +/- 9.8 mm Hg) during resuscitation (P = 0.0001). Survival for ETOH rats (70%) was significantly higher than controls (20%) (P = 0.003). Our data suggests that ETOH added to resuscitation from shock improves survival by inhibiting platelet activation and increasing tissue perfusion.

Soluble cytokine receptors and receptor antagonists are sequentially released after trauma

Cytokine receptors and receptor antagonists (RAs) have been identified in trauma patients. We hypothesized that after traumatic injury, a sequential release of soluble cytokine receptors and RAs may exist that mirrors the release of the primary cytokines themselves. Twenty-two patients were included in the study: 14 males and 8 females. The mean age was 30.1 +/- 12.5 (range, 19 to 71), and the mean Injury Severity Score was 28.7 +/- 12.6 (range, 4 to 57). There were 15 survivors and 7 nonsurvivors. Samples were collected on arrival to the emergency department and at serial intervals for up to 7 days. Monoclonal antibody enzyme-linked immunosorbent assay kits to tumor necrosis factor (TNF), soluble TNF-receptor (sTNF-R) 55 kd and 75 kd, interleukin (IL)-1 and IL-1 RA, and IL-2 and IL-2r were used. Sera from 22 healthy individuals were used as normal controls. No TNF, IL-1, or IL-2 could be detected in any patient sera after injury. Control levels for the soluble cytokine receptors and RAs were as follows: sTNF-R 55 kd, 607 +/- 89 pg/mL; sTNF-R 75 kd, 2,141 +/- 169 pg/mL; IL-1 RA, 291 +/- 35 pg/mL; and IL-2r, 426 +/- 53 U/mL. In trauma patients, both 55 kd and 75 kd sTNF-R were significantly elevated on arrival to the emergency department, with values of 2,441 +/- 506 pg/mL (p < 0.001) and 4,736 +/- 537 pg/mL (p < 0.001), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypoxia-induced alterations of neutrophil membrane receptors

Extravasation of leukocytes at sites of ischemia may mediate tissue injury. To determine how leukocyte accumulation may be induced by ischemia, effects of hypoxia on basal neutrophil expression of adhesion and activation receptors were examined. Effects of hypoxia upon preactivated cells were also studied. To determine whether regulation of expression is dependent on oxygen availability or on mitochondrial respiration, the effects of physical hypoxia (substitution of O2 by nitrogen) were compared with those of chemical hypoxia with sodium cyanide (NaCN). Leukocytes in whole blood (eight volunteers) were exposed either to hypoxia alone or to priming concentrations of lipopolysaccharide (LPS, 1 microgram/ml) followed by chemical hypoxia (NaCN, 1 mM) or physical hypoxia (PO2 of 1-10 torr) for various time intervals. Room air was controlled and hypoxic cells were labeled with fluorescent monoclonal antibodies to integrins CD18 and CD11b or to the 55-kDa TNF alpha cell surface receptor (TNFR). Receptor concentrations were measured by flow cytometry. Data were analyzed by ANOVA/Student's t test. Physical hypoxia increased expression of both CD11b and CD18 over time and augmented their LPS-induced up-regulation. Isolated chemical hypoxia did not change neutrophil expression of CD11b or CD18, but partially inhibited neutrophil CD11b and CD18 up-regulation by LPS. LPS-induced TNFR down-regulation was not affected by physical hypoxia, which failed to alter TNFR expression in this model.(ABSTRACT TRUNCATED AT 250 WORDS)

A technique for repair of traumatic parasternal lung herniation: case report

A case of traumatic lung herniation through an area of costalsternal separation in a 36-year-old male is presented. Persistent pain and the threat of strangulated lung tissue prompted repair that was accomplished with an expanded polytetrafluoroethylene Gortex tissue patch.

Respiratory distress in traumatized and burned children

Incidence and significance of respiratory failure after trauma in children was the subject of this study. One thousand nine hundred eighty-nine pediatric trauma patients (aged 18 years or less) were treated at the authors' level I trauma center between 1985 and 1993. Of these, 364 (18%) were intubated. Their mechanisms of injury were: motor vehicle accidents in 93 (25%), pedestrians struck by vehicles in 93 (25%), motorcycle or bicycle accidents in 55 (15%), gunshot and stab wounds in 43 (12%), major burns (> 20% BSA) in 31 (9%), 14 of whom also had smoke inhalation, falls in 25 (7%), sport-related injuries in 9 (2%), and child abuse in 8 (2%). Average injury severity score of intubated patients was 27.0 +/- 21.4. Average trauma score was 11.7 +/- 4.1. Of the intubated patients, 248 (68%) had head injuries, 153 (42%) chest injuries, and 114 (31%) abdominal and pelvic injuries. Ninety-three (25%) of intubated patients died within 5 days of injury: 70 of head injury, 23 of multiple major organ injury. Intubation was required for more than 5 days in 77 patients (21%); 50 (14%) of these patients met criteria for respiratory distress syndrome (RDS): 12 (24% of RDS patients) died. Two of the deaths were multiply traumatized patients, and 10 were patients with burns and smoke inhalation. The authors conclude that RDS is uncommonly the cause of death in pediatric trauma patients. Burned patients with RDS are an exceptional group, with significant mortality.

Diagnostic procedures for catheter malfunction in programmable implantable intraperitoneal insulin infusion devices

OBJECTIVE

To evaluate the roles of 1) abdominal radiography, 2) a pressure diagnostic procedure (PDP) using a standardized diluent infusion into the catheter sideport, and 3) radiocontrast imaging of the catheter lumen as procedures for diagnosing catheter malfunction in diabetic patients implanted with a programmable intraperitoneal infusion device.

RESEARCH DESIGN AND METHODS

Sixteen type I diabetic patients implanted with Infusaid programmable intraperitoneal insulin pumps were studied. The ability of the above three procedures to assist diagnosis of catheter malfunction and distinguish between occlusion and catheter breakage was retrospectively analyzed. Glycated hemoglobin was measured to determine the clinical importance of catheter malfunctions and decreases in pump flow due to insulin aggregation in the pump chamber.

RESULTS

Mean glycated hemoglobin levels increased significantly from 8.0 +/- 0.3 to 9.0 +/- 0.4% (P < 0.05) before and after catheter malfunction, but not during pump flow slowdowns. Mean peak pressure during PDP was 1.96 +/- 0.14 psi (P < 0.01 vs. normal) in reversibly occluded catheters and 1.86 +/- 0.35 psi (P < 0.05 vs. normal) in broken catheters, compared with 1.32 +/- 0.23 psi in normal catheters. Decay times during PDP were > 50 s for both reversibly occluded and broken catheters (P < 0.001 vs. normal of 3.6 +/- 0.82 s). Abdominal radiographs and sideport injections of contrast material were used to distinguish the types of broken catheters.

CONCLUSIONS

Catheter breakage and occlusion are complications in implantable insulin infusion systems and result in metabolic deterioration. The presence of a sideport allows pressure data and radiographic procedures to assist in determining the cause of catheter malfunction. A diagnostic algorithm was generated to improve efficiency in investigating catheter problems.

ATP-MgCl2 added to resuscitation improves survival in an experimental model of hemorrhagic shock

The administration of ATP-MgCl2 may be of benefit in the treatment of shock by improving cellular metabolic function during resuscitation. Prior studies have reported data from hemorrhage models in which heparinized shed blood is returned both during shock and in resuscitation. The purpose of this study was to test the effects of ATP-MgCl2 therapy upon blood pressure and survival in an animal model of hemorrhagic shock utilizing crystalloid (Lactated Ringer's) resuscitation. Adult male Sprague-Dawley rats (340-360 g) were bled 27 cc/kg and maintained in shock for 45 min. At the end of the shock period, animals were resuscitated with crystalloid at twice the original hemorrhage volume. A blinded three-arm study was conducted and animals were assigned to receive either Lactated Ringer's (LR) with placebo, LR with MgCl2, or LR with ATP-MgCl2. Blood pressure was monitored throughout the procedure and survival time was noted. Post-resuscitation MAP was increased in animals treated with ATP-MgCl2. ATP-MgCl2 added to resuscitation significantly improved 72-h survival over that of control (LR) animals, and animals treated with MgCl2 alone.

Trauma causes sustained elevation of soluble tumor necrosis factor receptors

BACKGROUND

Soluble tumor necrosis factor receptors (sTNF-R) are thought to modulate the systemic effects of tumor necrosis factor (TNF) by binding to serum TNF and preventing its interaction with target organs. Recently, it has been shown that traumatic injury causes the early release of the soluble forms of the 55 and 75 kDa membrane receptors for TNF. This study was done to determine the magnitude of TNF receptor elevation after trauma, to delineate the duration of this elevation, and to determine if sTNF-R levels correlate with severity of injury and outcome.

STUDY DESIGN

One hundred injured patients treated at a Level I Trauma Center were included in the study (74 males, 26 females, mean age of 29.4 years [range of ten to 72 years], mean injury severity score of 16.8 [range of zero to 75]). Serum samples were drawn from these patients beginning within one hour of injury and continuing for as many as 15 days. Samples were analyzed using polyclonal ELISA assays for TNF and sTNF 55 and 75 kDa receptor levels; control levels of receptor were determined from healthy volunteers.

RESULTS

Tumor necrosis factor was not measurable, but trauma caused immediate elevation of both receptor levels (within one hour of injury). Receptor levels remained elevated for as many as 15 days after injury. Late variations in levels were related to complications, that is, hypoxia, infection, and sepsis. Levels were significantly more elevated in critically ill patients and nonsurvivors.

CONCLUSIONS

We conclude that sTNF-R levels are significantly elevated after trauma, in the absence of measurable TNF. Levels are elevated for variable periods of time, which seem to depend on the severity of injury and complications.

Amrinone improves survival in hemorrhagic shock

Amrinone is a noncatecholamine inotropic agent used clinically in the management of heart failure. The purpose of this study was to determine if intravenous (i.v.) infusion of amrinone has beneficial effects during resuscitation from experimental hemorrhagic shock. Effectiveness was defined as significantly improved survival rate. Mean arterial pressure (MAP) and tissue oxygen tension (pO2) were measured to assess the physiologic effects of amrinone. Two separate randomized and blinded survival trials were conducted. In each trial, rats were randomly assigned to either a control group (n = 10) or an experimental group (n = 10). All animals were bled 27 ml/kg over 2 minutes and maintained in shock for 45 minutes before resuscitation. Resuscitation in placebo (control) animals was with 54 ml/kg (2 times the hemorrhage volume) Lactated Ringer's solution over 1 hour, whereas resuscitation in drug-treated animals was with a 0.75 mg/kg bolus amrinone over 3 minutes followed by 54 ml/kg Lactated Ringer's solution and 5 ug/kg/min infusion over 1 hour. Results were that resuscitation with amrinone significantly increased MAP, tissue pO2, and survival over resuscitation with Lactated Ringer's alone (P < 0.05). In both trials, survival rates increased by more than 66 per cent in the amrinone groups.

Clinical and laboratory evaluation of an electrosurgical laparoscopic trocar

Electrosurgical energy may be utilized as an adjunct to mechanical force for insertion of laparoscopic trocars. The advantage of this approach may be better operator control of insertion, with less risk of intraperitoneal and retroperitoneal injury. To assess the safety and efficacy of electrosurgical trocars, we compared them to mechanical trocars in clinical and animal trials. During 100 trocar introductions in 25 laparoscopic cholecystectomies, insertion force was measured. In contrast to mechanical trocars, which required progressively more force to insert as size increased, electrosurgical trocars required the same low insertion force regardless of size. No wound complications occurred. In animal experiments, wound healing (measured histologically and by bursting strength) was normal and equivalent for mechanical and electrosurgical insertions. We conclude that electrosurgical trocars require less force for insertion and do not impair wound healing. Electrosurgical trocars may thus offer important safety advantages over mechanical trocars.

A method to determine the adequacy of resuscitation using tissue oxygen monitoring

The change in tissue PO2 in response to an increased inspired O2 challenge may be related to the state of cellular oxygenation, and hence the adequacy of resuscitation. To test this hypothesis, we measured tissue PO2 during inspired O2 challenges in 29 injured patients during acute resuscitation or intensive care unit monitoring. The O2 challenge test had 100% sensitivity and specificity in detecting flow-dependent O2 consumption in invasively monitored patients in the intensive care unit. During acute resuscitation, 60% of patients had negative initial O2 challenge test results, indicating that flow-dependent O2 consumption might have been present. Of nine such patients, five had subsequent positive O2 challenge test results after fluid resuscitation, indicating successful resuscitation. Four patients (27% of acute resuscitations), however, had repeatedly negative findings, possibly indicating persistent inadequate cellular oxygenation despite fluid resuscitation. Other commonly measured variables did not differentiate these patients. Monitoring of tissue PO2 during an inspired O2 challenge may be a useful test for determining the adequacy of resuscitation from hypovolemic shock.

Insulin antibody responses after long-term intraperitoneal insulin administration via implantable programmable insulin delivery systems

OBJECTIVE

To determine whether insulin antibodies are generated in diabetic patients after short- and long-term intraperitoneal insulin use and, if so, whether they are of potential clinical interest. Insulin antibodies commonly develop in diabetic patients who use subcutaneous human insulin, although their clinical significance remains controversial. Few data are available regarding insulin antibody responses to intraperitoneal insulin.

RESEARCH DESIGN AND METHODS

We studied insulin antibody levels and clinical diabetes control in 25 type 1 diabetic patients treated for 3-6 years with intraperitoneal surfactant-stabilized porcine modified human insulin delivered by implantable programmable insulin delivery systems.

RESULTS

All patients had preimplantation insulin antibody levels < 20 microU/ml, with a mean value of 2 +/- 2 microU/ml (1 SD). Mean antibody levels increased throughout the study period to a mean maximum of 197 +/- 326 microU/ml (P < 0.02) with 11 of 25 (44%) patients' levels exceeding 20 microU/ml (insulin responders). The mean time to significant antibody development was 21.8 +/- 4.4 months. Of the 11 responder patients, 4 had clinical syndromes that consisted of increasing daily insulin requirements and/or nocturnal hypoglycemia despite minimal nighttime basal insulin infusion rates associated with peak antibody levels > 200 microU/ml. None of the nonresponder patients (antibody levels < 20 microU/ml) had these clinical findings.

CONCLUSIONS

Our results indicate that insulin antibody levels observed during intraperitoneal administration of human insulin are 1) similar to those reported during subcutaneous administration; although the rise in antibody level may be delayed compared with subcutaneous human insulin, 2) associated with a patient subset who are insulin antibody responders after switching from subcutaneous to intraperitoneal human insulin, 3) associated with a decrease in levels among responder patients regardless of whether they discontinue or continue pump use, and 4) associated with increased insulin needs and/or nocturnal hypoglycemia despite minimal basal rate insulin infusion at nighttime when antibody levels exceed 200 microU/ml.

Radiation exposure from cervical spine radiographs

Radiation exposure to hospital personnel during 41 cervical spine radiographs of 30 multiply injured patients was prospectively evaluated. A digital dosimeter was attached to the exposed torso of personnel applying upper extremity traction or managing the airway. Radiation exposure was measured during each radiograph. Any exposure of one or more milliroentgen was detectable. No radiograph resulted in a measurable radiation exposure. Multiple radiographs (up to five exposures) also did not register even the minimum recordable exposure, demonstrating that exposure is less than 1.0 mR per radiograph (P < .05). We conclude that hospital personnel, even those applying traction or managing the airway, are not at risk of significant radiation exposure at the time of cervical spine radiographs.