Biomedical subjects

Alan B Marr

Publications and source records attributed to Alan B Marr.

4 recordsLinked to original sources

PubMed2005

Unsafe at any age: a retrospective review of all-terrain vehicle injuries in two level I trauma centers from 1995 to 2003.

BACKGROUND: All-terrain vehicles (ATVs) are popular recreational and utility vehicles. In 1984, Cogbill published an article regarding three-wheelers. These are no longer manufactured, but the injury and death rate with four-wheeled ATVs is high and disproportionately affects young riders. METHODS: We conducted a retrospective review at two Level I trauma centers from January 1994 to April 2003. Statistical analysis was performed using the SAS V8.2 program. Values of p < 0.05 were significant. RESULTS: Two hundred eight patients were identified. There were no differences identified in demographics, mechanism, types of injury, Injury Severity Score (ISS), or Glasgow Coma Scale (GCS) score. Seventy-five percent were male and 84% were white. The mean age was 23 +/- 13 years. The average ISS was 12.3 +/- 9 and the mean GCS score was 13.1 +/- 3.7. Injury mechanisms were loss of stability (33%), separation of rider from ATV (32%), and ATV versus stationary object (27%). ISS for ages 12 to 15 years was significantly higher than for other ages (14.5 vs. 11.5, p = 0.04, Wilcoxon rank sum test) and included more major head injuries (40.4% vs. 21.8%, p = 0.09, Wilcoxon rank sum test). They experienced fewer spinal fractures (3.9% vs. 15.4%, p = 0.03) and pelvic injuries (0% vs. 9%, p = 0.02, Wilcoxon rank sum test). The GCS score in this group was lower (12.3 vs. 13.4, p = 0.03, Wilcoxon rank sum test). CONCLUSION: Adolescent ATV riders have more severe injuries and more head injuries than other age groups. Prevention efforts should target this group.

Abdominal Injuries↗

PubMed2004

Preload optimization using "starling curve" generation during shock resuscitation: can it be done?

Preload-directed resuscitation is the standard of care in U.S. trauma centers. As part of our standardized protocol for traumatic shock resuscitation, patients who do not respond to initial interventions of hemoglobin replacement and fluid volume loading have optimal preload determined using a standardized algorithm to generate a "Starling curve." We retrospectively analyzed data from 147 consecutive resuscitation protocol patients during the 24 months ending August 2002. Fifty (34%) of these patients required preload optimization, of which the optimization algorithm was completed in 36 (72%). The average age of those who required preload optimization was 44 +/- 3 years vs. 34 +/- 1 years for patients who did not. Execution of the algorithm caused PCWP to increase from 18 +/- 1 mmHg to a maximum of 25 +/- 2 mmHg and CI to increase from 3.2 +/- 0.1 L/min m(-2) to 4.5 +/- 0.4 L/min m(-2). Algorithm logic determined PCWP = 24 +/- 2 to be optimal preload at the maximum CI = 4.8 +/- 0.4, and as the volume loading threshold for the remaining time of the resuscitation process. Starling curve preload optimization was begun 6.5 +/- 0.8 h after start of the resuscitation protocol and required 36 +/- 5 min and 4 +/- 0.4 fluid boluses (1.6 +/- 0.2 L). Comparison of early response of those patients who required preload optimization and those who did not indicated hemodynamic compromise apparent in the 1st 4 h of standardized resuscitation. We conclude that preload optimization using sequential fluid bolus and PCWP-CI measurement to generate a Starling curve is feasible during ICU shock resuscitation, but that there is the disadvantage that increasing and maintaining high PCWP may contribute to problematic tissue edema.

Abdominal Injuries↗

PubMed2004

Gastric feeding as an extension of an established enteral nutrition protocol.

BACKGROUND: Indiscriminate gastric feeding in ICU patients imposes unacceptable risks of aspiration. Believing that a subset of ICU patients can be fed safely via the stomach, we have developed a protocol to identify appropriate patients and guide the bedside clinician in how to safely and effectively feed via the stomach. METHODS: A literature search was done to identify appropriate medical literature. High grade evidence along with local expert opinions were used to develop a protocol. This protocol has been refined and implemented. RESULTS: Based on perceived risk of aspiration, patients are assigned enteral access (ie, stomach vs. distal post-pyloric). Enteral formula is selected based on patient characteristics. It is then advanced by a standard protocol with specific precautions while monitoring for symptoms of intolerance. Management of intolerance is dictated by the type and severity of intolerance. CONCLUSION: We have implemented a gastric feeding into a subset of our ICU patients. Gastric feeding requires certain precautions but appears to be safe. With more experience and better understanding of the pathogenesis gastroparesis, we believe that most ICU patients should be able to safely feed into the stomach. This is logistically easier than post-pyloric feeding and offers physiologic advantages.

Journal Article↗

PubMed2002

An analysis of Eastern Association for the Surgery of Trauma practice guidelines for cervical spine evaluation in a series of patients with multiple imaging techniques.

We conducted a retrospective review of 124 consecutive patients who received all of the following studies between October 1998 and December 1999: three-view plain films (3VPF), full CT survey (CTS), and MRI of the cervical spine. We compared the EAST guidelines for 1) patients with persistent neck pain, 2) those with neurologic deficits (NDs), and 3) those who were obtunded in our study group to determine whether EAST recommendations would risk a significant missed injury rate. The average age was 28 years (range 5 months-78 years). There were 94 males and 30 females. The mean Injury Severity Score (ISS) was 16.8 and the mean Glasgow Coma Score (GCS) 10.87. The most common mechanism of injury was motor vehicle crash (58%) followed by falling (15%), auto versus pedestrian (9%), all-terrain vehicle accident (4%), assault (3%) and other (11%). For comparisons we identified a group of 33 patients with normal mental status and normal 3VPF. Twenty patients had MRI for persistent neck pain. Eleven of 20 had normal MRI. The nine abnormal MRIs showed: six ligamentous injuries, two cord compressions, and one nonligamentous soft-tissue injury. Thirteen of the 33 patients had MRI for ND. Six had normal MRI and all these NDs resolved. The remaining seven MRIs showed: two disc herniations, two cord contusions, one cord edema, one lumbar fracture, and one brachial plexus avulsion. We also examined a group of 51 obtunded patients with normal 3VPF. Thirty-six of 51 had normal CTS and MRI. Ten patients had an abnormal MRI, two an abnormal CTS, and three abnormal MRI and CTS. No obtunded patient with an adequate 3VPF had an injury identified below C2 using CTS and MRI. In the 10 patients with abnormal MRI the mean age was 28.4 years, the mean GCS 6.6 (P = 0.0025), and the mean ISS 24.3 (P = 0.03) (Wilcoxson two-sample test). The injuries identified by MRI were four disc herniations, two ligamentous injuries, two soft-tissue traumas, one meningeal tear, and one cord transection. Thirty per cent of patients with persistent neck pain had potentially unstable injuries not detected by 3VPF or CTS. Fifty-four per cent of patients with ND had abnormal MRI. Twenty-two per cent of obtunded patients with normal 3VPF and CTS had an abnormal MRI. These patients have a significantly lower GCS and a higher ISS. Six per cent of these injuries were potentially unstable. Our data support EAST guidelines for patients with persistent neck pain and ND. The guidelines for obtunded patients appear safe in detecting bony injury but may not be sensitive enough for unstable ligamentous injury and significant disc herniations.

Adolescent↗