Ketamine-Xylazine Anesthesia in Rats: Intraperitoneal versus Intravenous Administration Using a Microsurgical Femoral Vein Access.

BACKGROUND: Ketamine-xylazine is a frequently used combination for anesthesia in microsurgically operated rats and can be administered by intraperitoneal (IP) or intravenous (IV) injection. Both methods are associated with relatively high misadministration rates. In the present study, we want to introduce a femoral vein access that requires microsurgical cannulation but enables a 100% administration rate. METHODS: In this study, the maximal time of anesthesia was analyzed, time to response, latency time, and the total need for anesthetic agents in IP (n = 200) and IV (n = 40) anesthesia in Wistar rats for the purpose of microvascular operations. IV injections were achieved with an inserted microcatheter that was applied via a microsurgical femoral vein access. RESULTS: The time needed for the placement of the microcatheter was 5.76 ± 0.89 minutes. Maximal time of anesthesia (IP vs. IV) was 7.02 ± 1.92 versus 21.78 ± 5.77 hours (p < 0.0001), time to response was 137.5 ± 3.91 versus 18 ± 2.18 seconds (p < 0.0001), latency time 35.53 ± 3.21 versus 27.8 ± 2.88 minutes (p < 0.0001), and total volume of anesthetic 1.42 ± 0.39 versus 2.78 ± 0.73 mL (p < 0.0001), respectively. CONCLUSION: IV administration using the microsurgical femoral vein access is a feasible method with a quicker response rate and a 100% administration rate. Furthermore, it enables longer anesthesia, for example, complex microsurgical or other experimental procedures in the rat.

Pronator quadratus repair after volar plating of distal radius fractures or not? Results of a prospective randomized trial.

BACKGROUND: The purpose of the present study was to investigate the influence of the pronator quadratus (PQ) muscle repair following volar plate fixation of distal radius fractures with special regards to the forearm pronation strength. During the early recovery period of 3 months, an improvement of pronation strength and functional scorings was hypothesized for the PQ repair when compared to no repair. METHODS: The inclusion criteria were (1) men or women between 18 and 80 years, (2) isolated, closed fractures of the distal radius, (3) A2 to B2 types of fracture according to the AO fracture classification system, (4) primary volar locking plate osteosynthesis. Patients were randomized to group A = PQ repair and group B = no repair. Follow-up examinations after 6 and 12 weeks included bilateral isometric pronation strength measurement, range of motion, the QuickDASH and the Mayo-Wrist-Score, and a visual analog scale (VAS). RESULTS: 60 patients (n = 31 in group A and n = 29 in group B) with an average age of 54 years (range 22-77 years) returned for both follow-up visits. The pronation strength measurements showed no significant differences between groups (PQ repair vs. no repair) neither at 6 weeks nor at 12 weeks. Additionally, no statistical significant differences were noted for ROM, QuickDASH-Score or Mayo-Wrist-Score. The VAS scoring revealed a significant decreased pain level after PQ repair at 6 weeks postoperatively (p = 0.017). CONCLUSION: An improved pronation strength after PQ repair in the early rehabilitation period could not be confirmed. However, the PQ repair might reduce pain in the early postoperative period. TRIAL REGISTRATION NUMBER: NCT02595229 (ClinicalTrials.gov, registered 02 November 2015).

Significance of Traumatic Macroamputation in Severely Injured Patients: An Analysis of the Traumaregister DGU®.

Treatment of patients with traumatic macroamputations is challenging. The aim of this study is to analyze the significance of this type of injury in TraumaRegister DGU® (TR-DGU) and to depict the rate of formal surgical ablation of the traumatically induced amputation, epidemiologic data, as well as outcome in severely injured patients with amputations. We acquired data from the TR-DGU of the German Trauma Society (DGU). The inclusion criteria for our study were Injury Severity Score (ISS) greater than 9, macroamputation, and available data about the Abbreviated Injury Scale (AIS) code. A total of 48,908 of 67,425 patients had an ISS greater than 9 and available data about the AIS code. In total, 926 (1.9%) of 48,908 patients had an immediate traumatic macroamputation on-scene. Thereof, 298 patients (32.2%) had a macroamputation of the arms, 605 patients (65.3%) had an amputation of the legs, and 23 patients (2.5%) had both. Among them, 457 patients (49.4%) with a macroamputation had monotrauma. In total, 126 patients (13.6%) underwent replantation and 800 patients (86.4%) underwent formal surgical ablation of the traumatically induced amputation. Seventy-six (23.7%) of 321 patients with upper-extremity amputations and 53 (8.4%) of 628 patients with lower-extremity amputations underwent replantation. Mortality in patients with replantation was lower (5.6% vs. 19.6%, P < 0.001). Standardized mortality rate was lower for patients with replantation (0.71, 95% confidence interval, 0.20-1.21 vs. 0.94, 95% confidence interval, 0.80-1.10; P = 0.26). Glasgow Outcome Scale (GOS) was significantly better for patients with replantation (34.0%; GOS score 5) as compared with patients without replantation (20.7%; GOS score 5; P < 0.001). In borderline patients (defined according to the orthopedic damage control principles), 91.5% received formal surgical ablation of the traumatically induced amputation and 8.5% underwent replantation. The rate of formal surgical ablation of the traumatically induced amputation is higher when principles of damage control surgery are applied. The replantation rate in the upper extremity is higher than in the lower extremity. The less ISS and base excess and the higher blood pressure, hemoglobin value, and thromboplastin time are, the safer the decision for replantation seems to be.

Spinal cord injury--incidence, prognosis, and outcome: an analysis of the TraumaRegister DGU.

BACKGROUND CONTEXT: Little is known about the incidence of spinal cord injury (SCI) in polytrauma patients. PURPOSE: The purpose of this study was to analyze incidence, prognosis, and outcome of SCI in polytrauma patients. STUDY DESIGN/SETTING: This is a retrospective multicenter cohort study. PATIENT SAMPLE: A total of 57,310 patients of TraumaRegister DGU (2002-2012) of the German Trauma Society were included. Aim of this large multicentre database is a standardized documentation of severely injured patients. OUTCOME MEASURES: Outcome measures were mortality and Glasgow Outcome 4Scale. METHODS: Inclusion criteria were adult blunt trauma patients (age greater than 16 years) and injury severity score (ISS) greater than 16. The severity of SCI was based on the Abbreviated Injury Scale (AIS), and the outcome of patients was assessed with the Glasgow Outcome Scale (GOS). Factors with an impact on the outcome were analyzed with a logistic regression model. RESULTS: Four thousand two hundred eighty five (7.5%) of 57,310 patients sustained SCI. Mean age was 48.9±20.7 years, ISS 28.0±12, and 72.7% were men. Two thousand two hundred twenty two (3.9%) SCIs involved the cervical, 1,388 (2.4%) the thoracic, and 791 (1.4%) the lumbar spine. One hundred fifty-nine (7.2%) cervical spine injuries were associated with transient neurologic deficit (TND) (AIS 3), 612 (27.5%) with an incomplete paraplegia (AIS 4), 1,101 (49.6%) with a complete paraplegia (AIS 5), and 350 (15.8%) with a complete lesion above C3 (AIS 6). Lesions of the thoracic spine showed in 93 (6.7%) of the 1,388 lesions a TND (AIS 3), in 332 (23.9%) an incomplete paraplegia (AIS 4), and in 963 (69.4%) a complete lesion (AIS 5). In the lumbar region, lesions were distributed as follows: TND (AIS 3) 145 (18.3%), incomplete paraplegia (AIS 4) 305 (38.6%), and complete lesion 341 (43.1%). Sepsis and multiorgan failure were found more often in patients with AIS 5/6 lesions (p<.001). The hospital length of stay in SCIs was significantly longer. Most of the patients (85.8%) with SCI were treated in Level I trauma centers. Spinal cord injuries had a minor impact in the mortality. Only AIS 6 injuries resulted in a significantly higher mortality (64.6%). Adjusted logistic regression analysis (target variable: GOS 4 or 5, good outcome) showed that the following factors were significantly associated with an unfavorable outcome (p≤.02): AIS greater than or equal to 4, age greater than or equal to 60 years, resuscitation, severe head injury, shock on scene, and severity of injury (ISS per point). CONCLUSIONS: Spinal cord injury with a neurologic deficit could be found in every 13th patient with polytrauma. Over half of the patients with SCI suffer from complete cord lesion. In polytrauma patients, SCI only has a limited influence on the mortality, with exception of AIS 6 lesions. Complications such as multiorgan failure or sepsis and extended hospital length of stay are more frequent in SCI.

Whole-body CT in haemodynamically unstable severely injured patients--a retrospective, multicentre study.

BACKGROUND: The current common and dogmatic opinion is that whole-body computed tomography (WBCT) should not be performed in major trauma patients in shock. We aimed to assess whether WBCT during trauma-room treatment has any effect on the mortality of severely injured patients in shock. METHODS: In a retrospective multicenter cohort study involving 16719 adult blunt major trauma patients we compared the survival of patients who were in moderate, severe or no shock (systolic blood pressure 90-110,<90 or >110 mmHg) at hospital admission and who received WBCT during resuscitation to those who did not. Using data derived from the 2002-2009 version of TraumaRegister®, we determined the observed and predicted mortality and calculated the standardized mortality ratio (SMR) as well as logistic regressions. FINDINGS: 9233 (55.2%) of the 16719 patients received WBCT. The mean injury severity score was 28.8±12.1. The overall mortality rate was 17.4% (SMR  = 0.85, 95%CI 0.81-0.89) for patients with WBCT and 21.4% (SMR = 0.98, 95%CI 0.94-1.02) for those without WBCT (p<0.001). 4280 (25.6%) patients were in moderate shock and 1821 (10.9%) in severe shock. The mortality rate for patients in moderate shock with WBCT was 18.1% (SMR 0.85, CI95% 0.78-0.93) compared to 22.6% (SMR 1.03, CI95% 0.94-1.12) to those without WBCT (p<0.001, p = 0.002 for the SMRs). The mortality rate for patients in severe shock with WBCT was 42.1% (SMR 0.99, CI95% 0.92-1.06) compared to 54.9% (SMR 1.10, CI95% 1.02-1.16) to those without WBCT (p<0.001, p = 0.049 for the SMRs). Adjusted logistic regression analyses showed that WBCT is an independent predictor for survival that significantly increases the chance of survival in patients in moderate shock (OR = 0.73; 95%CI 0.60-0.90, p = 0.002) as well as in severe shock (OR = 0.67; 95%CI 0.52-0.88, p = 0.004). The number needed to scan related to survival was 35 for all patients, 26 for those in moderate shock and 20 for those in severe shock. CONCLUSIONS: WBCT during trauma resuscitation significantly increased the survival in haemodynamically stable as well as in haemodynamically unstable major trauma patients. Thus, the application of WBCT in haemodynamically unstable severely injured patients seems to be safe, feasible and justified if performed quickly within a well-structured environment and by a well-organized trauma team.