Peter Hinz

The severity of trauma determines the immune response to PF4/heparin and the frequency of heparin-induced thrombocytopenia

Heparin can induce heparin-induced thrombocytopenia (HIT). The combined effect of type of surgery (major vs minor) and heparin on this prothrombotic immune reaction to platelet factor 4 (PF4)/heparin was analyzed. In a randomized, double-blind study, trauma patients receiving low-molecular-weight (LMWH) or unfractionated heparin (UFH) for thrombosis prophylaxis were assessed for PF4/heparin-antibody seroconversion, HIT, and thrombosis according to type of surgery. The risk for seroconversion was higher than major versus minor surgery odds ratio, 7.98 [95% confidence interval, 2.06-31.00], P = .003, controlled for potential confounders, as was the risk for HIT (2.2% [95% confidence interval, 0.3%-4.1%] vs 0.0%, P = .010). During LMWH compared with UFH thromboprophylaxis, HIT (1 of 298 vs 4 of 316; P = .370) and PF4/heparin seroconversion (1.7% vs 6.6%; P = .002) were less frequent, driven by differences in patients undergoing major surgery (incidence of HIT: LMWH 0.8% vs UFH 4.0%; P = .180; seroconversion rates: 4.0% vs 17.0%; P = .001). After minor surgery, no case of HIT occurred. The severity of trauma and the need for major surgery strongly influence the risk of an anti-PF4/heparin immune response, which is then increased by UFH. In major trauma certoparin may be safer than UFH because it induces HIT-antibody seroconversion, and the corresponding risk of HIT, less frequently.

Risk assessment of the application of a plasma jet in dermatology

Regardless of the fact that several highly efficient antiseptics are commercially available, the antiseptic treatment of chronic wounds remains a problem. In the past, electrical plasma discharges have been frequently used in biometrical science for disinfection and sterilization of material surfaces. Plasma systems usually have a temperature of several hundred degrees. Recently, it was reported that cold plasma can be applied onto living tissue. In in vitro studies on cell culture, it could be demonstrated that this new plasma possesses excellent antiseptic properties. We perform a risk assessment concerning the in vivo application of a cold plasma jet on patients and volunteers. Two potential risk factors, UV radiation and temperature, are evaluated. We show that the UV radiation of the plasma in the used system is an order of magnitude lower than the minimal erythema dose, necessary to produce sunburn on the skin in vivo. Additionally, thermal damage of the tissue by the plasma can be excluded. The results of the risk assessment stimulate the in vivo application of the investigated plasma jet in the treatment of chronic wounds.

Drug delivery through the skin barrier enhanced by treatment with tissue-tolerable plasma.

Abstract:u2002 Most treatments in dermatology and cosmetology are based on the penetration of topically applied drugs into the skin or through the skin barrier to the target structure in the living tissue. In the case of healthy skin, scarcely 1% of the applied drugs pass the skin barrier, depending on their chemical properties. Therefore, different physical and chemical methods have been developed to stimulate the penetration process. All these methods are based on the partial destruction of the barrier. In this study, an electrical tissue‐tolerable plasma (TTP) was used to increase the penetration of a topically applied model drug (fluorescent dye) through the skin barrier. Using laser scanning microscopy, the distribution of the model drug in different depths of the skin was investigated. It was found that the plasma treatment of the skin is a very efficient process to deliver topically applied substances into the living tissue. In the case of the non‐plasma‐treated skin, it was found that the fluorescent dye could be detected exclusively on the skin surface. If the dye was applied to the TTP‐treated skin, it could be observed in high concentration also in deeper parts of the skin extending down to the stratum basale and the papillary structure.

Accidental circular saw hand injuries: trauma mechanisms, injury patterns, and accident insurance.

INTRODUCTIONnHand injuries due to circular saws are a common reason for patients seeking medical care in emergency departments. With respect to cases of insurance fraud, these injuries are of medico-legal interest. It is the aim of this study to investigate the critical circumstances of the incidents, the accident mechanism, and the specific injury patterns of circular saw related hand injuries with regard to accident insurance coverage.nnnPATIENTS AND METHODSnCircular saw related hand injuries for the years 1999 through 2007 were followed-up and assessed in detail. Type, severity and pattern of the injury were assessed. An accident analysis investigated characteristic of the activities, of the saws, of the stock/cutting material, operational activities of the operators prior to/at the time of the incident, and detailed information on the insurance status.nnnRESULTSnThe follow-up study encompassed 114 patients. A majority of these were covered by private or statutory accident insurances. Compensation payments were made in all cases. All lesions involved one hand, mainly the left non-dominant hand. Thumb and index were at highest risk for injury. One-finger injuries occurred mainly at the middle or distal phalanx. With increasing number of affected fingers, the level of the injury moved closer to the proximal phalanx. A majority of injuries occurred during do-it-yourself activities. Among blade contact injuries, the so-called kickback-mechanism was at highest risk.nnnCONCLUSIONnPositive circumstantial indications of a self-inflicted injury, which are often cited in the literature are less conclusive for the medico-legal decision finding. The detailed anatomic description of any lesions and the alleged accident mechanism as initially described by the patients in the emergency setting is the basis for any later accident reconstruction.

Blunt Criterion trauma model for head and chest injury risk assessment of cal. 380 R and cal. 22 long blank cartridge actuated gundog retrieval devices

BACKGROUNDnBlunt ballistic impact trauma is a current research topic due to the widespread use of kinetic energy munitions in law enforcement. In the civilian setting, an automatic dummy launcher has recently been identified as source of blunt impact trauma. However, there is no data on the injury risk of conventional dummy launchers. It is the aim of this investigation to predict potential impact injury to the human head and chest on the basis of the Blunt Criterion which is an energy based blunt trauma model to assess vulnerability to blunt weapons, projectile impacts, and behind-armor-exposures.nnnMETHODSnBased on experimentally investigated kinetic parameters, the injury risk of two commercially available gundog retrieval devices (Waidwerk Telebock, Germany; Turner Richards, United Kingdom) was assessed using the Blunt Criterion trauma model for blunt ballistic impact trauma to the head and chest.nnnRESULTSnAssessing chest impact, the Blunt Criterion values for both shooting devices were higher than the critical Blunt Criterion value of 0.37, which represents a 50% risk of sustaining a thoracic skeletal injury of AIS 2 (moderate injury) or AIS 3 (serious injury). The maximum Blunt Criterion value (1.106) was higher than the Blunt Criterion value corresponding to AIS 4 (severe injury). With regard to the impact injury risk to the head, both devices surpass by far the critical Blunt Criterion value of 1.61, which represents a 50% risk of skull fracture. Highest Blunt Criterion values were measured for the Turner Richards Launcher (2.884) corresponding to a risk of skull fracture of higher than 80%.nnnCONCLUSIONnEven though the classification as non-guns by legal authorities might implicate harmlessness, the Blunt Criterion trauma model illustrates the hazardous potential of these shooting devices. The Blunt Criterion trauma model links the laboratory findings to the impact injury patterns of the head and chest that might be expected.

Humane killers, human injury: functional outcome of vole captive bolt injuries.

BACKGROUNDnHigh-pressure blast injuries to the hand due to vole captive bolt devices are serious injuries that are to a great extent unknown to emergency care operators and trauma surgeons. There is no study on the functional outcome of these patients.nnnMETHODSnWe assessed the functional outcome of patients with injuries inflicted by vole captive bolt devices. Therefore, a protocol consisting of a physical examination and an assessment of static muscle power (grip and pinch strength) was performed. To capture the subjective experience of patients regarding their injury related disability and impairment, the DASH follow-up questionnaire was used. Based on clinical/radiologic findings and outcome, a classification of this unique subgroup of blast injuries was developed.nnnRESULTSnThe functional outcome of 34 patients suffering hand injuries due to captive bolt devices between 2004 and 2007 was assessed. A significant reduction of static muscle testing parameters compared with the uninjured hand was revealed. Fourteen patients lost a digit. Average time lost from work was 5.4 weeks.nnnCONCLUSIONnVole captive bolt device-related hand injuries are followed by deterioration of hand function. The present observations alarmed national authorities. The manufacturers were required to take engineering and teaching measures to rule out handling errors that were identified as leading cause of injury.

Mind your hand during the energy crunch: Functional Outcome of Circular Saw Hand Injuries

BackgroundAlthough injuries due to circular saws are very common all over the world, there is surprisingly little information available about their functional outcomes. As the socioeconomic impact of these injuries is immense and determined by the casualties disability and impairment, it is the objective of this study to present data on the functional outcome, disability, and impairment of hand injuries due to electric circular saws.MethodsPatients treated from 1999 through 2007 for circular saw-related hand injuries were contacted and asked for clinical follow-up assessment. The clinical follow-up protocol consisted of a physical examination and an assessment of static muscle power (grip and pinch strength). For assessment of the subjective experience of the patients regarding their injury-related disability and impairment, the DASH follow-up questionnaire was used. The occupational impact of these injuries was measured by number of lost working days. Finally, safety-related behaviour of the patients was investigated.Results114 Patients were followed-up on average 52 months after the injury. Average in-house treatment was 8.8 days. Average time lost from work was 14.8 weeks. A significant reduction of static muscle testing parameters compared with the uninjured hand was revealed for grip strength, tip pinch, key pinch, and palmar pinch. Average DASH score was 17.4 (DASH work 15.8, DASH sports/music 17.7). Most patients had more than ten years experience in using these power tools.ConclusionThe everyday occurrence of circular saw-related hand injuries followed by relatively short periods of in-house treatment might distort the real dimension of the patients remaining disability and impairment. While the trauma surgeons view is generally confined to the patients clinical course, the outcome parameters in this follow-up investigation, with loss of working time as the key factor, confirm that the whole socioeconomic burden is much greater than the direct cost of treatment.

Viability of Lucilia sericata maggots after exposure to wound antiseptics.

After debridement and before dressing a wound with maggots of calliphorid flies, one frequently performed step is the application of antiseptics to the prepared wound bed. However, the concomitant application of antiseptic agents during maggot therapy is regarded controversial as antiseptics may interfere with maggots viability. In this experimental in vitro study, the viability of fly maggots was investigated after exposure to various antiseptics frequently used in wound care. Here, we show that Lucilia sericata fly maggots can survive up to an hours exposure to wound antiseptics such as octenidine, povidone‐iodine or polihexanide. Concomitant short‐term application of wound antiseptics together with maggots on wound beds is tolerated by larvae and does not impair their viability.

Antimicrobial efficacy of preoperative skin antisepsis and clonal relationship to postantiseptic skin-and-wound flora in patients undergoing clean orthopedic surgery.

Nosocomial surgical site infections (SSI) are still important complications in surgery. The underlying mechanisms are not fully understood. The aim of this study was to elucidate the possible role of skin flora surviving preoperative antisepsis as a possible cause of SSI. We conducted a two-phase prospective clinical trial in patients undergoing clean orthopedic surgery at a university trauma center in northern Germany. Quantitative swab samples were taken from pre- and postantiseptic skin and, additionally, from the wound base, wound margin, and the suture of 137 patients. Seventy-four patients during phase I and 63 during phase II were investigated. Microbial growth, species spectrum, and antibiotic susceptibility were analyzed. In phase two, the clonal relationship of strains was additionally analyzed. 18.0xa0% of the swab samples were positive for bacterial growth in the wound base, 24.5xa0% in the margin, and 27.3xa0% in the suture. Only 65.5xa0% of patients showed a 100xa0% reduction of the skin flora after antisepsis. The microbial spectrum in all postantiseptic samples was dominated by coagulase-negative staphylococci (CoNS). Clonally related staphylococci were detected in ten patients [nine CoNS, one methicillin-susceptible Staphylococcus aureus (MSSA)]. Six of ten patients were suspected of having transmitted identical clones from skin flora into the wound. Ethanol-based antisepsis results in unexpected high levels of skin flora, which can be transmitted into the wound during surgery causing yet unexplained SSI. Keeping with the concept of zero tolerance, further studies are needed in order to understand the origin of this flora to allow further reduction of SSI.

Corrigendum to: Drug delivery through the skin barrier enhanced by treatment with tissue‐tolerable plasma

by treatment with tissue-tolerable plasma Olaf Lademann, Heike Richter, Martina C. Meinke, Alexa Patzelt, Axel Kramer, Peter Hinz, Klaus-Dieter Weltmann, Bernd Hartmann and Stefan Koch Institute of Hygiene and Environmental Medicine, Ernst Moritz Arndt University of Greifswald, Greifswald, Germany; Department of Dermatology and Allergology, Center of Experimental and Cutaneous Physiology (CCP), Charite¢ – Universitätsmedizin, Berlin, Germany; Department of Emergency Surgery, Medical Faculty, Ernst Moritz Arndt University of Greifswald, Greifswald, Germany; Leibniz Institute for Plasma Science and Technology e. V. (INP), Greifswald, Germany; Burncenter, Unfallkrankenhaus Berlin (UKB), Berlin, Germany; Institute of Pathology, HELIOS Klinikum Bad Saarow, Germany