Kenneth Davis

Effects of inhaled nitric oxide in patients with acute respiratory distress syndrome : Results of a randomized phase II trial

OBJECTIVES To evaluate the safety and physiologic response of inhaled nitric oxide (NO) in patients with acute respiratory distress syndrome (ARDS). In addition, the effect of various doses of inhaled NO on clinical outcome parameters was assessed. DESIGN Prospective, multicenter, randomized, double-blind, placebo-controlled study. SETTING Intensive care units of 30 academic, teaching, and community hospitals in the United States. PATIENTS Patients with ARDS, as defined by the American-European Consensus Conference, were enrolled into the study if the onset of disease was within 72 hrs of randomization. INTERVENTIONS Patients were randomized to receive placebo (nitrogen gas) or inhaled NO at concentrations of 1.25, 5, 20, 40, or 80 ppm. MEASUREMENTS AND MAIN RESULTS Acute increases in PaO2, decreases in mean pulmonary arterial pressure, intensity of mechanical ventilation, and oxygenation index were examined. Clinical outcomes examined were the dose effects of inhaled NO on mortality, the number of days alive and off mechanical ventilation, and the number of days alive after meeting oxygenation criteria for extubation. A total of 177 patients were enrolled over a 14-month period. An acute response to treatment gas, defined as a PaO2 increase > or =20%, was seen in 60% of the patients receiving inhaled NO with no significant differences between dose groups. Twenty-four percent of placebo patients also had an acute response to treatment gas during the first 4 hrs. The initial increase in oxygenation translated into a reduction in the FIO2 over the first day and in the intensity of mechanical ventilation over the first 4 days of treatment, as measured by the oxygenation index. There were no differences among the pooled inhaled NO groups and placebo with respect to mortality rate, the number of days alive and off mechanical ventilation, or the number of days alive after meeting oxygenation criteria for extubation. However, patients receiving 5 ppm inhaled NO showed an improvement in these parameters. In this dose group, the percentage of patients alive and off mechanical ventilation at day 28 (a post hoc analysis) was higher (62% vs. 44%) than the placebo group. There was no apparent difference in the number or type of adverse events reported among those patients receiving inhaled NO compared with placebo. Four patients had methemoglobin concentrations >5%. The mean inspired nitrogen dioxide concentration in inhaled NO patients was 1.5 ppm. CONCLUSIONS From this placebo-controlled study, inhaled NO appears to be well tolerated in the population of ARDS patients studied. With mechanical ventilation held constant, inhaled NO is associated with a significant improvement in oxygenation compared with placebo over the first 4 hrs of treatment. An improvement in oxygenation index was observed over the first 4 days. Larger phase III studies are needed to ascertain if these acute physiologic improvements can lead to altered clinical outcome.

Prospective, Randomized Comparison of Epidural Versus Parenteral Opioid Analgesia in Thoracic Trauma

OBJECTIVE To evaluate systemic versus epidural opioid administration for analgesia in patients sustaining thoracic trauma. SUMMARY BACKGROUND DATA The authors have previously shown that epidural analgesia significantly reduces the pain associated with significant chest wall injury. Recent studies report that epidural analgesia is associated with a lower catecholamine and cytokine response in patients undergoing elective thoracotomy compared with patient-controlled analgesia (PCA). This study compares the effect of epidural analgesia and PCA on pain relief, pulmonary function, cathechol release, and immune response in patients sustaining significant thoracic trauma. METHODS Patients (ages 18 to 60 years) sustaining thoracic injury were prospectively randomized to receive epidural analgesia or PCA during an 18-month period. Levels of serum interleukin (IL)-1beta, IL-2, IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha) were measured every 12 hours for 3 days by enzyme-linked immunosorbent assay. Urinary catecholamine levels were measured every 24 hours. Independent observers assessed pulmonary function using standard techniques and analgesia using a verbal rating score. RESULTS Twenty-four patients of the 34 enrolled completed the study. Age, injury severity score, thoracic abbreviated injury score, and length of hospital stay did not differ between the two groups. There was no significant difference in plasma levels of IL-1beta, IL-2, IL-6, or TNF-alpha or urinary catecholamines between the two groups at any time point. Epidural analgesia was associated with significantly reduced plasma levels of IL-8 at days 2 and 3, verbal rating score of pain on days 1 and 3, and maximal inspiratory force and tidal volume on day 3 versus PCA. CONCLUSIONS Epidural analgesia significantly reduced pain with chest wall excursion compared with PCA. The route of analgesia did not affect the catecholamine response. However, serum levels of IL-8, a proinflammatory chemoattractant that has been implicated in acute lung injury, were significantly reduced in patients receiving epidural analgesia on days 2 and 3. This may have important clinical implications because lower levels of IL-8 may reduce infectious or inflammatory complications in the trauma patient. Also, tidal volume and maximal inspiratory force were improved with epidural analgesia by day 3. These results demonstrate that epidural analgesia is superior to PCA in providing analgesia, improving pulmonary function, and modifying the immune response in patients with severe chest injury.

Blunt carotid artery injuries

BACKGROUND Blunt carotid artery trauma remains a rare but potentially devastating injury. Early detection and treatment remain the goals of management. Our objective was to identify patients sustaining blunt carotid injuries at a regional trauma center and report on the incidence, demographics, diagnostic workup, management, and outcome. STUDY DESIGN A retrospective chart review was performed of patients sustaining blunt carotid artery injury between 1990 and 1996. RESULTS Twenty patients were identified during the 7-year period. All patients suffered blunt trauma, with motor vehicle accidents being the most common mechanism, and the internal carotid the most frequently injured vessel. Associated injuries were present in all patients, with head (65%) or chest (65%) injuries being the most common. The combination of head and chest trauma (45%) was found to be associated with a 14-fold increase in the likelihood of carotid injury. Cerebral angiography was diagnostic in all patients and the majority were treated nonoperatively with anticoagulation. Twenty percent of patients were discharged with a normal neurologic exam, while 45% left with a significant neurologic deficit. Overall mortality was 5%. CONCLUSIONS Blunt carotid injuries are rare but are associated with significant morbidity and mortality. The combination of craniofacial and chest wounds should raise the index of suspicion for blunt carotid injury. Anticoagulation was associated with the least morbidity.

Cost and complications during in-hospital transport of critically ill patients : a prospective cohort study

We prospectively studied transport of a group of 100 surgery/trauma patients and a matched control group in the ICU. APACHE II scores for the two groups were 23 +/- 6 and 20 +/- 8. During transport both groups had ECG, heart rate, blood pressure, and oxygen saturation continuously monitored. We also determined the cost and results of transport for those patients requiring diagnostic testing. There were six diagnostic tests performed: CT scan of the abdomen (39%), CT scan of the head (31%), CT scan of the chest (8%), CT scan of the cervical spine (4%), angiography (14%), and tomography (4%). Average transport time was 74 +/- 16 minutes with a range of 20-225 minutes. Physiologic changes defined as a BP +/- 20 mm Hg, heart rate +/- 20 beats/min, respiratory rate +/- 5 breaths/min, or oxygen saturation +/- 5% for 5 minutes duration occurred in 66% of transported patients and 60% of ICU patients. There were no differences in arterial blood gas levels before and during transport. In 39% of transports, the results of diagnostic testing produced a change in patient management within 48 hours. Abdominal CT scanning and angiography were associated with the highest percentage of tests leading to a management change (51% and 57%). The average charge to the patient was

Prolonged use of heat and moisture exchangers does not affect device efficiency or frequency rate of nosocomial pneumonia.

612.00 and the average cost to the hospital

Comparison of volume control and pressure control ventilation: is flow waveform the difference?

452.00. Our results suggest that while physiologic changes are frequent during transport, they are also frequent in ICU patients as a consequence of the severity of illness.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of conventional mechanical ventilation and high-frequency ventilation. A prospective, randomized trial in patients with respiratory failure.

Objective: To determine whether use of a single heat and moisture exchanger (HME) for ≤120 hrs affects efficiency, resistance, level of bacterial colonization, frequency rate of nosocomial pneumonia, and cost compared with changing the HME every 24 hrs. Design: Prospective, controlled, randomized, unblinded study. Setting: Surgical intensive care unit at a university teaching hospital. Patients: A total of 220 consecutive patients requiring mechanical ventilation for >48 hrs. Interventions: Patients were randomized to one of three groups: a) hygroscopic HME (Aqua+) changed every 24 hrs (HHME‐24); b) hydrophobic HME (Duration HME) changed every 120 hrs (HME‐120); and c) hygroscopic HME (Aqua+) changed every 120 hrs (HHME‐120). Devices in all groups could be changed at the discretion of the staff when signs of occlusion or increased resistance were identified. Measurements and Main Results: Daily measurements of inspired gas temperature, inspired relative humidity, and device resistance were made. Additionally, daily cultures of the patient side of the device were accomplished. The frequency rate of nosocomial pneumonia was made by using clinical criteria. Ventilatory support variables, airway care, device costs, and clinical indicators of humidification efficiency (sputum volume, sputum efficiency) were also recorded. Prolonged use of both hygroscopic and hydrophobic devices did not diminish efficiency or increase resistance. There was no difference in the number of colony‐forming units from device cultures over the 5‐day period and no difference between colony‐forming units in devices changed every 24 hrs compared with devices changed after 120 hrs. The average duration of use was 23 ± 4 hrs in the HHME‐24 group, 73 ± 13 hrs in the HME‐120 group, and 74 ± 9 hrs in the HHME‐120 group. Mean absolute humidity was greater for the hygroscopic devices (30.4 ± 1.1 mg of H2O/L) compared with the hydrophobic devices (27.8 ± 1.3 mg of H2O/L). The frequency rate of nosocomial pneumonia was 8% (8:100) in the HHME‐24 group, 8.3% (5:60) in the HME‐120 group, and 6.6% (4:60) in the HHME‐120 group. Pneumonia rates per 1000 ventilatory support days were 20:1000 in the HHME‐24 group, 20.8:1000 in the HME‐120 group, and 16.6:1000 in the HHME‐120 group. Costs per day were

Comparison of Blood Gases during Transport Using Two Methods of Ventilatory Support

3.24 for the HHME‐24 group,

Institutional and Individual Learning Curves for Focused Abdominal Ultrasound for Trauma: Cumulative Sum Analysis

2.98 for the HME‐120 group, and

Techniques of Emergency Ventilation: A Model to Evaluate Tidal Volume, Airway Pressure, and Gastric Insufflation

1.65 for the HHME‐120 group. Conclusions: Changing the hydrophobic or hygroscopic HME after 3 days does not diminish efficiency, increase resistance, or alter bacterial colonization. The frequency rate of nosocomial pneumonia was also unchanged. Use of HMEs for >24 hrs, up to 72 hrs, is safe and cost effective.