In- and out-of-hospital outcomes following surgical stabilization of rib fractures in 80 years and older: A single-institution experience.

BACKGROUND: Surgical stabilization of rib fractures (SSRF) has demonstrated benefit in patients with flail chest and multiple displaced fractures. There is mounting evidence for SSRF following chest wall injury (CWI) for the geriatric trauma population. A recent multi-center retrospective study highlighted a mortality benefit even for those patients aged 80 years and older. The objective of this investigation was to review our institutional experience with both in- and out-of-hospital outcomes within this patient population following SSRF. METHODS: A retrospective review of patients 80 years and older was performed at a high-volume level 2 trauma center from 2017 to 2021. SSRF volume is routinely >60 cases per year. Perioperative, inpatient, and outpatient data were collected as available. Primary outcomes were inpatient and 90-day mortality. Secondary outcomes included discharge on narcotics and freedom from narcotics at 30 days. RESULTS: 50 patients were included for review. Mean age was 86 years and mechanism of injury was most often fall. 28 of 50 (56%) patients had flail chest (radiographic). Mean number of ribs fixated was 4.7 and time to surgery 2.5 days. Inpatient mortality was 3/50 (6%), 90-day mortality was 9/50 (18%) of which three were attributable primarily to CWI (6/50, 12%). Of patients with follow-up of 1 year and beyond, 27/28 were alive (96%). With respect to narcotic consumption, 45% (21/47) were discharged on narcotics with 90% (28/31; N limited by missing data) being narcotic-free at 30 days. CONCLUSION: In this high-risk patient population, inpatient mortality was comparably low to prior reports, though 90-day mortality was doubled when incorporating CWI-related deaths. Narcotic use was seen in the minority of patients upon discharge, and most progressed to being narcotic-free at 30 days post-hospitalization. Inpatient outcomes alone may not adequately define both the benefit and risk of SSRF performed in patients 80 years and older.

Surgical stabilization of severe chest wall injury following cardiopulmonary resuscitation.

BACKGROUND: Cardiopulmonary resuscitation (CPR) contributes to significant chest wall injury similar to blunt trauma. With benefits realized for surgical stabilization of rib fractures (SSRFs) for flail injuries and severely displaced fractures following trauma, SSRF for chest wall injury following CPR could be advantageous, provided good functional and neurologic outlook. Experience is limited. We present a review of patients treated with SSRF at our institution following CPR. METHODS: A retrospective analysis of patients undergoing SSRF following CPR was performed between 2019 and 2020. Perioperative inpatient data were collected with outpatient follow-up as able. RESULTS: Five patients underwent SSRF over the course of the 2-year interval. All patients required invasive ventilation preoperatively or had impending respiratory. Mean age was 59 ± 12 years, with all patients being male. Inciting events for cardiac arrest included respiratory, ventricular tachycardia, ventricular fibrillation, pulseless electrical activity, and anaphylaxis. Time to operation was 6.6 ± 3 days. Four patients demonstrated anterior flail injury pattern with or without sternal fracture, with one patient having multiple severely displaced fractures. Surgical stabilization of rib fracture was performed appropriately to restore chest wall stability. Mean intensive care unit length of stay was 9.8 ± 6.4 days and overall hospital length of stay 24.6 ± 13.2 days. Median postoperative ventilation was 2 days (range, 1-15 days) with two patients developing pneumonia and one requiring tracheostomy. There were no mortalities at 30 days. One patient expired in hospice after a prolonged hospitalization. Disposition destination was variable. No hardware complications were noted on outpatient follow-up, and all surviving patients were home. CONCLUSION: Chest wall injuries are incurred frequently following CPR. Surgical stabilization of these injuries can be considered to promote ventilator liberation and rehabilitation. Careful patient selection is paramount, with surgery offered to those with reversible causes of arrest and good functional and neurologic outcome. Experience is early, with further investigation needed. LEVEL OF EVIDENCE: Therapeutic, Level V.

Computed tomographic angiography versus conventional angiography for the diagnosis of blunt cerebrovascular injury in trauma patients.

BACKGROUND: Blunt cerebrovascular injuries (BCVI) in trauma patients are rare but potentially devastating injuries, particularly if the diagnosis is delayed. Conventional angiography (CA) has been the screening and diagnostic modality of choice for identifying BCVI. With the advent of high-resolution computed tomography (CT), CT angiography has become a common modality for the screening of BCVI. A liberalized screening approach has suggested that cerebrovascular injuries are missed in many patients; however, no standard BCVI screening protocol exists. Early diagnosis of the BCVI can prevent long-term sequelae. METHODS: In this prospective study, all patients received a CT angiogram (16-slice or 64-slice) at the time of injury assessment and followed 24 hours to 48 hours later with CA of the cerebrovasculature. RESULTS: A total of 158 patients were enrolled in the study. CA identified 32 injuries to the cerebrovasculature in 27 patients; CT detected only 13 true injuries (40.6%) in 12 patients. Of the 32 injuries, 11 were carotid artery injuries and 21 were of the vertebral artery. Seventy-four patients were screened with the 16-slice CT scanner with an overall sensitivity of 29%, and 84 patients were screened with the 64-slice CT scanner with an overall sensitivity of 54%. The combined specificity and sensitivity of 16- and 64-slice CT in detecting BCVI were 0.97 (95% confidence interval: 0.92-0.99) and 0.41 (95% confidence interval: 0.22-0.61), respectively. CONCLUSION: Neither 16- nor 64-slice CT angiography is as accurate as CA as a screening tool for BCVI.

Clinical detection of precataractous lens protein changes using dynamic light scattering.

OBJECTIVE: To use dynamic light scattering to clinically assess early precataractous lens protein changes. METHODS: We performed a cross-sectional study in 380 eyes of 235 patients aged 7 to 86 years with Age-Related Eye Disease Study clinical nuclear lens opacity grades 0 to 3.8. A dynamic light-scattering device was used to assess alpha-crystallin, a molecular chaperone protein shown to bind other damaged lens proteins, preventing their aggregation. The outcome measure was the alpha-crystallin index, a measure of unbound alpha-crystallin in each lens. The association of the alpha-crystallin index with increasing nuclear opacity and aging was determined. RESULTS: There was a significant decrease in the alpha-crystallin index associated with increasing nuclear lens opacity grades (P < .001). There were significant losses of alpha-crystallin even in clinically clear lenses associated with aging (P < .001). The standard error of measurement was 3%. CONCLUSIONS: Dynamic light scattering clinically detects alpha-crystallin protein loss even in clinically clear lenses. alpha-Crystallin index measurements may be useful in identifying patients at high risk for cataracts and as an outcome variable in clinical lens studies. CLINICAL RELEVANCE: The alpha-crystallin index may be a useful measure of the protective alpha-crystallin molecular chaperone reserve present in a lens, analogous to creatinine clearance in estimating renal function reserve.

Pharmacologic vitreolysis with microplasmin increases vitreous diffusion coefficients.

BACKGROUND: Pharmacologic vitreolysis is a new approach to improve vitreo-retinal surgery and ultimately to liquefy and detach the vitreous from the retina to eliminate the contribution of the vitreous to retinopathy. The mechanism of action of the agents being developed for pharmacologic vitreolysis remains unclear. The effect of microplasmin on vitreous diffusion coefficients was investigated using the non-invasive technique of dynamic light scattering (DLS). METHODS: Vitreous diffusion coefficients in 18 intact porcine eyes were measured in vitro with dynamic light scattering (DLS). DLS was performed on all specimens at 37 degrees C 30 min after injections of human recombinant microplasmin at doses ranging from 0.125 to 0.8 mg, with 20-nm tracer nanospheres. RESULTS: DLS findings in untreated porcine vitreous were similar to the previously described findings in bovine and human vitreous. Microplasmin increased porcine vitreous diffusion coefficients in a dose-dependent manner (correlation coefficient, r=0.93), with an 85% increase after a 30-min exposure to the maximum dose. CONCLUSIONS: Pharmacologic vitreolysis with human recombinant microplasmin increases vitreous diffusion coefficients in vitro. The results of these studies have implications for the dosing, route of administration, duration of action and methods of determining efficacy in future studies of pharmacologic vitreolysis to enhance vitreo-retinal surgery, as well as the design of clinical trials to induce prophylactic posterior vitreous detachment.

Particle-size and velocity measurements in flowing conditions using dynamic light scattering.

The noninvasive optical technique of dynamic light scattering (DLS) is routinely used to characterize dilute and transparent submicrometer particle dispersions in laboratory environments. A variety of industrial and biological applications would, however, greatly benefit from on-line monitoring of dispersions under flowing conditions. We present a model experiment to study flowing dispersions of polystyrene latex particles of varying sizes under varying flow conditions by using a newly developed fiber-optic DLS probe. A modified correlation function proposed in an earlier study is applied to the analysis of extracting the size and velocity of laminar flowing particulate dispersions. The complementary technique of laser Doppler velocimetry is also used to measure the speed of moving particles to confirm the DLS findings.

Aggregation of lens crystallins in an in vivo hyperbaric oxygen guinea pig model of nuclear cataract: dynamic light-scattering and HPLC analysis.

PURPOSE: The role of oxygen in the formation of lens high-molecular-weight (HMW) protein aggregates during the development of human nuclear cataract is not well understood. The purpose of this study was to investigate lens crystallin aggregate formation in hyperbaric oxygen (HBO)-treated guinea pigs by using in vivo and in vitro METHODS: methods. Guinea pigs were treated three times weekly for 7 months with HBO, and lens crystallin aggregation was investigated in vivo with the use of dynamic light-scattering (DLS) and in vitro by HPLC analysis of water-insoluble (WI) proteins. DLS measurements were made every 0.1 mm across the 4.5- to 5.0-mm optical axis of the guinea pig lens. RESULTS: The average apparent diameter of proteins in the nucleus (the central region) of lenses of HBO-treated animals was nearly twice that of the control animals (P < 0.001). Size distribution analysis conducted at one selected point in the nucleus and cortex (the outer periphery of the lens) after dividing the proteins into small-diameter and large-diameter groups, showed in the O2-treated nucleus a threefold increase in intensity (P < 0.001) and a doubling in apparent size (P = 0.03) of large-diameter aggregate proteins, compared with the same control group. No significant changes in apparent protein diameter were detected in the O2-treated cortex, compared with the control. The average diameter of protein aggregates at the single selected location in the O2-treated nucleus was estimated to be 150 nm, a size capable of scattering light and similar to the size of aggregates found in human nuclear cataracts. HPLC analysis indicated that one half of the experimental nuclear WI protein fraction (that had been dissolved in guanidine) consisted of disulfide cross-linked 150- to 1000-kDa aggregates, not present in the control. HPLC-isolated aggregates contained alphaA-, beta-, gamma-, and zeta-crystallins, but not alphaB-crystallin, which is devoid of -SH groups and thus does not participate in disulfide cross-linking. All zeta-crystallin present in the nuclear WI fraction appeared to be there as a result of disulfide cross-linking. CONCLUSIONS: The results indicate that molecular oxygen in vivo can induce the cross-linking of guinea pig lens nuclear crystallins into large disulfide-bonded aggregates capable of scattering light. A similar process may be involved in the formation of human nuclear cataract.