Heart rate variability predicts trauma patient outcome as early as 12 h: implications for military and civilian triage

BACKGROUND: Our previous work demonstrated dense physiological data capture in the intensive care unit (ICU), defined a new vital sign Cardiac Volatility Related Dysfunction (CVRD) reflecting reduced heart rate variability, and demonstrated CVRD predicts death during the hospital stay adjusting for age and injury severity score (ISS). We hypothesized a more precise definition of variability in integer heart rate improves predictive power earlier in ICU stay, without adjusting for covariates. METHODS: Approximately 120 million integer heart rate (HR) data points were prospectively collected and archived from 1316 trauma ICU patients, linked to outcome data, and de-identified. HR standard deviation was computed in each 5-min interval (HR(SD5)). HR(SD5) logistic regression identified ranges predictive of death. The study group was randomly divided. Integer heart rate variability (% time HR(SD5) in predictive distribution ranges) models were developed on the first set (N = 658) at 1, 2, 4, 6, 8, 12, and 24 h after ICU admission, and validated on the second set (N = 658). RESULTS: HR(SD5) is bimodal, predicts death at low (0.1-0.9 bpm) and survival at high (1.8-2.6 bpm) ranges. HRV predicts death as early as 12 h (ROC = 0.67). HRV in a moving 1-h window is a simple graphic display technique. CONCLUSIONS: Dense physiological data capture allows calculation of HRV, which: 1) Independently predicts hospital death in trauma patients at 12 h; 2) Shows early differences by mortality in groups of patients when viewed in a moving window; and 3) May have implications for military and civilian triage.     

Consensus guidelines on screening for hypopituitarism following traumatic brain injury

Primary objective: The goal of this consensus statement is to increase awareness among endocrinologists and physicians treating patients with traumatic brain injury (TBI) of the incidence and risks of hypopituitarism among patients with TBI.

Rationale: TBI poses significant risk to the pituitary gland, leading to elevated risks of diabetes, hypopituitarism and other endocrinopathies. Signs and symptoms associated with hypopituitarism often mimic the sequellae of TBI, although the severity of symptoms is not necessarily related to the severity of the injury. Patients with TBI-induced hypopituitarism may benefit both physically and psychologically from appropriate hormone replacement therapy (HRT). Participants at this unique consensus meeting attempted to define and spearhead an approach to increase awareness of the risks of TBI-induced endocrinopathies, in particular growth hormone deficiency (GHD), and to outline necessary and practical objectives for managing this condition.

Recommendations: Systematic screening of pituitary function is recommended for all patients with moderate-to-severe TBI at risk of developing pituitary deficits. Patients with hypopituitarism benefit from appropriate hormonal replacement and prospects for rehabilitation of patients with TBI-induced hypopituitarism may be enhanced by appropriate HRT. Further exploration of this possibility requires: (1) active collaboration between divisions of endocrinology and rehabilitation at the local level to perform a screening of pituitary function in patients after TBI, (2) creation of a consultancy service by endocrine societies for use by rehabilitation centres, (3) development of continuing medical education (CME) programmes that can be offered as crossover training to the physicians who manage the care of patients with TBIs, (4) targeting of patient organizations with educational information for dissemination to patients and their families, (5) continued efforts to more clearly define the population at greatest risk of TBI-induced hypopituitarism and (6) monitor results of efficacy studies as they become available to evaluate whether and how much replacement therapy can improve the symptoms of individuals with TBI-induced hypopituitarism.     

Gunshot wounds to the head: gang- and non-gang-related injuries and outcomes

Primary objective: This study examined the differences between gang and non-gang-related incidents of penetrative missile injuries in terms of demographics, motivation, intra-cranial pathology, transit time, injury time and clinical outcome. Research design: Retrospective and prospective chart review. Methods and procedures: Between 1985-1992, 349 patients with penetrating missile injuries to the brain presenting to LAC-USC were studied. Experimental interventions: Inclusion criteria were implemented to keep the cohort as homogenous as possible. Patients excluded were those with multiple gunshot wounds, non-penetrating gunshot wounds to the head, systemic injuries and cases in which the motivation for the incident was unknown. Main outcomes and results: Gang-related shooting slightly out-numbered non-gang-related incidents. Demographic analysis showed both a male and Hispanic predominance for both gang- and non-gang-related victims and significant differences in gender, race and age. Occipital entrance sites were more common in the gang-related vs temporal entrance sites in the non-gang-related. Mean transit time to the emergency department for gang-related shootings was less than non-gang-related shootings (24.4 vs 27.8 minutes). Most shooting incidents took place between 6 pm and 3 am. No difference between survival and outcome was noted between gang and non-gang victims. Conclusions: Significant differences were found between gang- and non-gang-related shooting victims in terms of demographics, entrance site and transit time. No difference was found between injury time, survival and outcome between gang and non-gang populations.     

Hydrophilic-coated catheters for intermittent catheterisation reduce urethral micro trauma: a prospective, randomised, participant-blinded, crossover study of three different types of catheters

OBJECTIVE: To compare two hydrophilic-coated (SpeediCath and LoFric and one uncoated gel-lubricated catheter (InCare Advance Plus) concerning withdrawal friction force and urethral micro trauma. METHODS: 49 healthy male volunteers participated in this prospective, randomised, blinded, crossover study of three different bladder catheters. The withdrawal friction force was measured, and urine analysis of blood, nitrite and leucocytes, microbiological analysis of urine cultures and subjective evaluation of the catheters were performed. RESULTS: 40 participants completed the study and were included in the analysis. SpeediCath exerted a significantly lower mean withdrawal friction force and work than the gel-lubricated uncoated catheter, whereas LoFric exerted a significantly higher mean friction force than both of the other catheters. The hydrophilic catheters caused less microscopic haematuria and less pain than the gel-lubricated uncoated catheter. Furthermore, 93% of the participants preferred the hydrophilic catheters. CONCLUSION: Hydrophilic-coated catheters perform better than uncoated catheters with regard to haematuria and preference. SpeediCath, but not LoFric, exerts less withdrawal friction force than InCare Advance Plus.     

Clinical applications of neuroimaging with susceptibility-weighted imaging

Susceptibility-weighted imaging (SWI) consists of using both magnitude and phase images from a high-resolution, three-dimensional, fully velocity compensated gradient-echo sequence. Postprocessing is applied to the magnitude image by means of a phase mask to increase the conspicuity of the veins and other sources of susceptibility effects. This article gives a background of the SWI technique and describes its role in clinical neuroimaging. SWI is currently being tested in a number of centers worldwide as an emerging technique to improve the diagnosis of neurological trauma, brain neoplasms, and neurovascular diseases because of its ability to reveal vascular abnormalities and microbleeds.     

Comparison of retrospectively ECG-gated and nongated MDCT of the chest in an emergency setting regarding workflow, image quality, and diagnostic certainty

Purpose This study aims to assess the influence of ECG-gated acquisition on workflow and to compare image quality and diagnostic certainty for retrospectively ECG-gated and nongated multidetector computed tomography of the chest in the emergency suite. Materials and methods Thirty-two consecutive patients were referred for both an ECG-gated and a nongated CT to rule out traumatic thoracic injury (n=15) or acute aortic dissection (n=17). The time from the start of the transportation from the emergency suite to the CT room until the start of the CT scan was recorded. Using a scoring system, the image quality of axial images and multiplanar reformats, the presence of disease, and the subjective diagnostic certainty were assessed with regard to the vascular structures, the bone structures, and the lung parenchyma. Results The time needed for transportation and patient preparation was 12.1±1.7 min (8.1–14.5 min). The motion artifacts of the thoracic aorta and the supra-aortic vessels were significantly reduced in the ECG-gated data acquisition compared with the nongated technique (P<0.001). Subjective diagnostic certainty for assessment of the aorta was significantly better using ECG gating. The image quality of the lung parenchyma (P<0.005), the spine (P<0.005), and the ribs (P<0.002) was inferior in the ECG-gated data sets but did not compromise the detection rate of traumatic lesions and fractures. Conclusion Performing ECG gating in the emergency room did not slow down the diagnostic workup. ECG-gated acquisition performed better in the assessment of the aorta, but image quality for lung and bone structures was slightly reduced. Further studies are required to assess the influence of the imaging technique on the diagnostic outcome.     

Thrombolytic therapy followed by stenting for renal artery dissection secondary to blunt trauma

A 18-year-old man presented at our clinic with pain in the right flank following a motorbike accident. The diagnosis of renal artery dissection followed by thrombosis was made by computed tomography and confirmed by angiography. Successful revascularization was performed by means of repeated transcatheter injection of small doses of thrombolytic agents within the vessel, followed by deployment of a self-expandable stent. There were no complications, and the patient recovered well. Six months after stent placement, a selective renal angiogram showed excellent flow through the stented portion of the artery and normal parenchyma enhancement in the right kidney.     

Analysis of multiple casualty incidents - a prospective cohort study

Background:  Our aim was to report the rate and causes for multiple casualty incidents (MCI) to analyse the prehospital part of responding to MCIs, report mortality and find areas for improvement.
Methods:  A prospective cohort study conducted in an urban emergency medical service (EMS) between 1.3.1998 and 28.2.2004.
Results:  Fifty-nine MCIs involving 263 patients (167 walking, 96 non-walking) occurred. The incidence of MCIs was 1.8/100,000 inhabitants year⁻¹. Traffic accidents were the most common cause followed by residential fires, intoxications and stabbings or shootings. Early MCI alarm by the dispatching centre was performed in 18 MCIs. Deviations from standard emergency medical care occurred in 12% of patients. Lack of immobilization of the neck or back in trauma patients and lack of administration of 100% oxygen in suspected carbon monoxide intoxication were the most common deviations. Deviations were related to the lack of presence of on-scene medical command ( P =  0.0013) and inadequate resources ( P =  0.0342). One hundred and ninety-two patients were transported to emergency departments. Mortality during the prehospital phase was 4.9% (13/263) and during the next 28 days 2.3% (6/263). Adequate resources for safe and effective management of a MCI were related to an early MCI alarm by the dispatching centre ( P =  0,022) and to the presence of on-scene medical command ( P <  0,001).
Conclusions:  Traffic accidents, residential fires and intoxications were the leading causes for MCIs. Emergency medical service could respond to most MCIs efficiently and safely. Majority of deviations from standard medical care seemed potentially preventable. Several areas for improvement were identified. From prehospital links, the dispatching centre and on-scene medical command had a vital role in the successful management of MCIs.     

Homeostatic synaptic plasticity can explain post-traumatic epileptogenesis in chronically isolated neocortex

Chronically isolated neocortex develops chronic hyperexcitability and focal epileptogenesis in a period of days to weeks. The mechanisms operating in this model of post-traumatic epileptogenesis are not well understood. We hypothesized that the spontaneous burst discharges recorded in chronically isolated neocortex result from homeostatic plasticity (a mechanism generally assumed to stabilize neuronal activity) induced by low neuronal activity after deafferentation. To test this hypothesis we constructed computer models of neocortex incorporating a biologically based homeostatic plasticity rule that operates to maintain firing rates. After deafferentation, homeostatic upregulation of excitatory synapses on pyramidal cells, either with or without concurrent downregulation of inhibitory synapses or upregulation of intrinsic excitability, initiated slowly repeating burst discharges that closely resembled the epileptiform burst discharges recorded in chronically isolated neocortex. These burst discharges lasted a few hundred ms, propagated at 1-3 cm/s and consisted of large (10-15 mV) intracellular depolarizations topped by a small number of action potentials. Our results support a role for homeostatic synaptic plasticity as a novel mechanism of post-traumatic epileptogenesis.     

Repair of injuries to the thoracic aorta and great vessels: Auckland, New Zealand 1995-2004

BACKGROUND: Traumatic injury to the aorta and great vessels is a surgical emergency with survivors who reach hospital typically having suffered multiple injuries. There are several diagnostic and treatment options available, with new modalities emerging to challenge the gold standards. A review of recent trends in management of these injuries in Auckland, New Zealand was carried out and patient outcomes assessed. METHODS: The charts of patients admitted to Auckland and Green Lane Hospital's cardiothoracic intensive care unit, with a diagnosis of injury to the thoracic aorta or great vessels since 1995 were retrospectively reviewed. Imaging techniques, injury types and treatment methods were analysed along with survival and neurological morbidity. RESULTS: In the study period our unit operated on 29 cases of traumatic rupture of the thoracic aorta or great vessels. Digital subtraction angiography and more recently, multidetector computed tomography scanning have been used to diagnose the injury. Twenty-seven injuries were to the aorta and two to the innominate artery. The 30-day survival rate of those reaching the operating theatre was 90%. There was one case of postoperative hemiparesis and five cases of recurrent laryngeal nerve injury, but none of spinal cord ischaemic injury. Endoluminal stent grafting was carried out for one patient, without complication. CONCLUSIONS: Good survival rates exist for those who reach surgery for traumatic rupture of the aorta or great vessels. Multidetector computed tomography scanning is an alternative to digital subtraction angiography, potentially reducing treatment delay. In addition endoluminal grafting as opposed to open repair has been reported as a safe technique. The injury remains a surgical emergency requiring urgent diagnosis and transfer to an equipped cardiothoracic unit for definitive treatment.