[Surgical treatment of bites]

Fifteen-minute consultation: Management of mammalian bites in children-from local wound care to prophylactic antibiotics

Animal and human bites are a common reason for emergency consultation, especially in children. The most common complication of bite wounds is local infection. Systemic infections are much rarer. The key in reducing the risk of infection after a mammalian bite is local wound management with either primary or delayed closure. The benefit of administering prophylactic antibiotics is controversial.In this review, we provide a summary of the current evidence for the management of mammalian bites in children, including recommendations for appropriate investigations, wound management, administration of prophylactic and therapeutic antibiotics and the prevention of systemic infections.

[Trauma surgical relevance of bite injuries by animals and humans]

Bite injuries require differentiated treatment due to the deeply inoculated polymicrobial pathogen spectrum, possible concomitant injuries and pronounced soft tissue damage. Dog bites are the most common bite injuries but are less complicated to heal than human and cat bites. The location of the bite greatly depends on the age and the size of the bite victim as well as the type of bite perpetrator. In every case detection of the pathogen should be carried out to provide the best possible adapted treatment in the event of an exacerbation. The primary antibiotic treatment should be empirical with amoxicillin + clavulanic acid or ampicillin + sulbactam and, if necessary, adjusted according to the antibiogram. Depending on the findings, surgical treatment includes excision of the bite canal and a customized wound debridement. It is important to check the vaccination status of those involved and if indicated, to carry out postexposure prophylaxis for tetanus and rabies.

[Caution: aggressive! Dog bite injuries in clinical forensic medicine]

Younger children in particular are at risk of becoming victims of dog attacks due to their small size. Such a biting incident can fulfil various criminal offences. In order to be able to satisfy possible legal claims, the injuries should be documented by forensic medicine and thus be legally binding. Therefore, close cooperation between the treating surgeons and forensic experts is recommended. A retrospective analysis of the cases of dog bite injuries in children and adults treated by clinical forensic medicine at the University Medical Center Rostock was carried out under various aspects. Adult casualties were predominantly injured on the lower extremities. The children examined were predominantly bitten on the head, neck and face region as well as the upper extremities. Injury severity ranged from skin redness to severe substance defects with loss of body structures. The biting dog was known in about half of the cases. In order to avoid dog bites in children, parents as well as children should be trained in dealing with dogs.

[Bite Wounds Should not be Irrigated by Syringe. An Anatomic Study]

In the literature about treatment of animal and human bite injuries, it is often recommended that bite wounds should be cleaned with a syringe and button cannula or plastic catheter. This is supposed to clean deeper wound sections and remove contamination and foreign bodies. Recent papers recommend cautious irrigation without high pressure.

MATERIAL AND METHOD

 In eight cadavers, artificial bite wounds were produced in typical locations. These wounds were irrigated by syringe and button cannula using diluted ink. The pressure of irrigation was limited to "no noticeable pressure".

RESULTS

 In all cases, more than half of the irrigation volume remained inside the victim´s organism, following anatomic structures and spreading over large areas.

CONCLUSION

Irrigation fails to clean the wound but increases the risk of contaminating the surrounding structures. Hence, the authors recommend that bite wounds should not be irrigated by syringe and button cannula.

[Infections of the Hand after Bite Injuries]

Bite injuries are common. Along with the resulting complications, they represent approximately 1-2 % of all emergency department visits. In over 75 %, the hands are affected. In Northern Europe, bites and subsequent infections are mainly caused by dogs and cats but also by humans.Up to 40 % of all hand infections are caused to bite injuries. Due to the multiple and complex compartments as well as the low soft tissue coverage of functionally relevant structures, even the smallest and most superficial bite injuries of the hand lead to infections. Any bite injury to the hand may subsequently may result in a fulminant infection and, rarely, even death.The spectrum of pathogens from the oral flora of the biting animal or person is diverse and includes aerobic and anaerobic bacterial strains. Bite injuries represent a major challenge for both the injured person and the attending physician. The rate of complications has been shown to increase with delayed medical consultation, lack of medical care and inadequate wound care. In this review, we discuss the types and complications of bite wounds, their potential risk of infection, their pathogen spectrum and appearance, and their effective treatment.

Risk factors for reoperation in primary hand infections: a multivariate analysis

INTRODUCTION

Severe hand infection might cause severe morbidity including stiffness, contracture and possibly amputation. The purpose of this study was to analyse the current epidemiology of adult acute hand infections in a European Hand Surgery Centre and to identify risk factors for secondary surgery.

MATERIALS AND METHODS

We retrospectively analyzed a cohort of 369 consecutive patients with primary infection of the hand that were admitted to our department and required operative treatment. The following variables were recorded: demographics, medical history, cause and location of infection, laboratory values, cultured microorganisms and reoperation rate. Univariate logistical regression was used to identify variables associated with reoperation and backward selection was applied to identify the final multiple variable model.

RESULTS

The mean age at the time of operation was 50.5 years (SD 16.1, range 19-91) and 65.6% of patients were male. Sharp cuts or lacerations were the most common cause (29.0%) for hand infections. 81 different species were cultivated and in 47 patients (12.7%), the cultures were positive for more than one organism. Staphylococcus aureus was the most common cultured organism (19.5%). There were relatively few cases of methicillin-resistant Staphylococcus aureus (2.2%). 80 patients (21.7%) needed more than one operation. We identified three risk factors for reoperation in a multivariate analysis: an elevated value of C-reactive protein at the time of admission, involvement of multiple sites and bacterial growth in culture.

CONCLUSION

The rate of infections with MRSA in this European cohort was lower compared to reports from the USA. Thus, hand surgeons should choose their empiric antibiotic therapy depending on their patient population. The knowledge of risk factors for severe hand infections might help surgeons to identify patients at risk for additional surgery early.