Treatment of common dog bites: Infection risk factors

ORIGINAL CONTRIBUTION

Treatment of Common Dog Bites: Infection Risk Factors Michael L. Callaham, MD . Fresno, California

In a retrospective study of 106 patients with complete follow-up of dog bites treated in the emergency department the following factors greatly increased the risk of infection: age greater than 50 years, delay in seeking treatment, location on an upper extremity, and puncture wounds. Debridement and irrigation decreased the incidence of infection, and sutured wounds were not more likely to become infected than those left open. Prophylactic antibiotics provided no benefit in this series. In the literature, overall infection rates varied widely according to the various patient populations. Up to 50% of infections from dog bites are caused by pasturella multocida, and the remainder by a wide range of organisms, including streptococcus. Ninety-five percent of these organisms will be sensitive to penicillin. Callaham ME: Treatment of common dog bites: Infection risk factors.

JACEP 7:83-87, March, 1978. bites, animal, dog.

I NTRODUCTION Dog bite is an e x t r e m e l y common problem in this country, r e p o r t e d as occ u r r i n g about 500/ to 700/100,000 population. 1 The incidence has been r i s i n g r e c e n t l y 2 , 2 About 500,000 to 1 million people a y e a r are b i t t e n by dogs in the U n i t e d States. 3-5 Despite the prevalence of this problem, few s y s t e m a t i c studies have been done. Of those done, m a n y have been preselected reports of severe cases by plastic surgeons, not r e p r e s e n t a t i v e of e i t h e r dog bites in g e n e r a l or typical e m e r g e n c y d e p a r t m e n t cases. Therefore, t h e r e is little objective information a v a i l a b l e to m a k e r a t i o n a l decisions r e g a r d i n g suturing, prophylactic antibiotics, and other forms of t r e a t m e n t . For this reason, we decided to review the l i t e r a t u r e and conduct a retrospective study of common dog bites seen in our e m e r g e n c y d e p a r t m e n t .

MATERIALS AND METHODS Valley Medical Center (VMC) is a large, active county t e a c h i n g hospital, one of three major hospitals in the area, and a r e a s o n a b l y r e p r e s e n t a t i v e crosssection of the c o m m u n i t y is seen in the e m e r g e n c y d e p a r t m e n t . The p a t i e n t c h a r t s on 432 cases of dog bites seen in the VMC E m e r g e n c y D e p a r t m e n t between J u l y 1974 and March 1977 were reviewed. Of these, 106 (24.5%) cases h a d a d e q u a t e follow-up in the e m e r g e n c y d e p a r t m e n t , (ie, a t least t h r e e days of follow-up after the bite), and a d e q u a t e information on the c h a r t for review. These c h a r t s were reviewed for age, race, sex, time between bite a n d i n i t i a l t r e a t m e n t , l e n g t h of follow-up, exact description of wound, w h e t h e r debrided, i r r i g a t e d , or sutured, use of antibiotics, a d m i n i s t r a t i o n of t e t a n u s toxoid, a n d results of follow-up, including hospitalization. W h e n specific i n f o r m a t i o n was l a c k i n g for some cases, eg, w h e t h e r the Presented a! Summer Emergencies: Focus on Controversy, Monterey, California, May, 1977. From the Department of Emergency Medicine, Valley Medical Center, Fresno, California. Address for reprints: Michael L. Callaham, MD, Assistant Chief, Department of Emergency Medicine, Valley Medical Center, 445 South Cedar Avenue, Fresno, California 93702.

7:3 (Mar) 1978

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wound was debrided or not, the case was excluded for the particular variable. Results were tested statistically by the chi-square method. 6 We a s s u m e d the p a t i e n t s who did not r e t u r n for follow-up had trivial bites, m a n y not even h a v i n g broken the skin. The trivial n a t u r e of many bites has been reported elsewhere.% s To test our assumption t h a t our follow-up cases represented t h o s e c a s e s a s s o c i a t e d w i t h some morbidity, a telephone survey was m a d e of 50 r a n d o m l y selected patients who did not r e t u r n after the i n i t i a l visit. All of these stated that t h e i r w o u n d s h a d h e a l e d to t h e i r satisfaction without further medical care. RESULTS Of our cases with follow-up, 18 (16.6%) were i n f e c t e d ( T a b l e 1). However, only 4.1% of all cases of dog bite p r e s e n t i n g to our emergency d e p a r t m e n t were infected. Results of the c h a r t r e v i e w are s u m m a r i z e d (Tables 1 to 7).

Table 1 WOUND LOCATION AND INFECTION RATE* n = 106

Location

Total No

Scalp Face Torso Leg Foot Arm Hand, All

8 23 4 34 1 18 20

% Infected (No) 12.5 4 0 15 0 27 30

(1) (1) (5) (5) (6)

readily available; dogmatic statem e n t s (no pun intended) r e g a r d i n g t r e a t m e n t are rife, b u t s u p p o r t i n g studies are scarce. Large studies~, 7 show t h a t 93% of patients visiting a n emergency dep a r t m e n t for a dog bite r e c e i v e t e t a n u s toxoid (TT), 10% r e q u i r e suturing, and 1% are hospitalized. Of people bitten by a dog, 77% had one or more medical visits and/or disability days as a result. 1 The a v e r a g e cost of such an episode in 1972 was $49, w h i c h did n o t i n c l u d e lost wages. 1 In this same study, 1 34% of patients with follow-up were sutured (7.8% of all dog bites seen). Of those followed, 4% were a d m i t t e d to the h o s p i t a l ( a p p r o x i m a t e l y 1% of all cases). Infection Rate Overall infection rates vary widely. I n one l a r g e study, s o n l y 3.4% were infected, and all on arrival. I n a n o t h e r s t u d y of t y p i c a l bites, 9 5.1% of dog bites were infected (with pasturella). In a small plastic surgery practice study ~ of dog bite victims, all on prophylactic antibiotics, 6% b e c a m e i n f e c t e d . I n the m u c h - q u o t e d s t u d y by Lee a n d Buhr, 1° 59 patients had a 29% infection rate, b u t these were all t h o u g h t to be c o n t a m i n a t e d w o u n d s w h e n first seen and only cases bacteriologically studied were included in this study. A retrospective study 1~ of 150 typical e m e r g e n c y d e p a r t m e n t dog bite cases had a 2% infection rate with good surgical t r e a t m e n t of the w o u n d s . I n a n o t h e r study, 7 a b o u t 25% of admitted patients developed infections, 6% of all dog bite cases seen. Our overall infection rate was

0 50 16.6

Total No

% Infected

(No)

% of all Infected Cases

Puncture

45

22

(10)

40

Laceration 1 layer

46

13

(6)

24

Laceration 2 layer

15

(1)

4

Laceration 2.5 cm

40

15

(6)

24

Laceration 2.5 cm

21

9

(2)

8

Type

The a v e r a g e follow-up for infected cases was 7.23 days; for noninfected cases, 6.57 days. The difference is not significant. DISCUSSION Useful information regarding t r e a t m e n t of typical dog bites seen in the e m e r g e n c y d e p a r t m e n t is n o t 12/84

Up to 50% of infections from dog bites are caused by p a s t u r e l l a multocida.% 13 T h e i n c i d e n c e is much greater with cat bites24 Fifty-four percent of dogs have been found to carry pasturella on their tonsils, 10% in their nostrils, and 14% on their g u m s 2 As a m a t t e r of fact, 3% of vete r i n a r y s t u d e n t s carried p a s t u r e l l a in their throats. ~ This organism causes a rapidly developing cellulitis; 70% of infections present w i t h i n one day of injury, a n d 90% by two days. ~4 I n f l a m m a t i o n , pain, and swelling are typical, with serosanguineous drainage in 20%. R e g i o n a l l y m p h a d e n o p a t h y develops i n one t h i r d , and low g r a d e s y s t e m i c s y m p t o m s in 14%2,13,14 The infection may be low grade a n d s m o l d e r i n g a n d the w o u n d is slow to heal even with proper therapy. S e p t i c e m i a or even osteomyelitis or t e n o s y n o v i t i s m a y develop, p a r t i c u l a r l y w i t h p u n c t u r e wounds of the h a n d . 9,1s F o r t u n a t e l y , this o r g a n i s m is very sensitive to penicillin, as well as most o t h e r antibiotics2 The rest of the i n f e c t i o n s are caused by a wide range of organisms, about 20 have been reported, with beta hemolytic streptococcus, streptococcus viridans, and staphylococcus aureus accounting for the vast major-

WOUND TYPE AND INFECTION RATE*

(2) (18)

*Significant at the 99% confidence level, except for scalp and leg, where the difference is not significant.

Organisms

Table 2

Punctures and wounds infected on arrival excluded Sutu red 3 Not sutured 4 All locations 108

4.1%; 16.6% of patients with emer. gency d e p a r t m e n t follow-up were infected, b u t most of those who failed to r e t u r n were believed to have no complications, based on a telephone survey. This rate compares favorably w i t h a 5% r a t e for l a c e r a t i o n s in general. 12

6.6

*Significant at the 99% confidence level.

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ity. U s u a l l y t h e s e will a p p e a r as mixed i n f e c t i o n s . ~° A n a v e r a g e of 32% of dogs studied are carriers of s t a p h l y c o c c u s ; w i t h 10% to 16% p e n i c i l l i n r e s i s t a n t . 17 O r g a n i s m s were c u l t u r e d from the majority of wounds (defined as contaminated) in the f o r m e r study, w h e t h e r or n o t they later became infected. No particular o r g a n i s m s were well correlated with s u b s e q u e n t infections, except pasturella, which u s u a l l y went on to cause clinical infection. P s e u d o m o n a s , b a c i l l u s species, p n e u mococci, diphtheroids, proteus species, a n d o t h e r s were g r o w n from wounds t h a t did not become infected. • Several c l i n i c a l l y infected wounds were s t e r i l e by b o t h a e r o b i c a n d anaerobic culture; this false negative culture p h e n o m e n o n has also been reported in other studies. 4

Table 3 INFECTION RATE AND TREATMENT DELAYS* Elapsed Time - - Bite to First Visit 0-24 Hrs Total No of Cases

24-48 Hrs

79

9

48 Hrs 10

8.8 (7)

66.6 (6)

40 (4)

Infected on arrival

0

22

30 (3)

Not infected on arrival

100

78

% Infected (No)

Developed infection Did not develop i nfectio n % Total infections

8.8 (7)

44

(2)

70 (4)

10 (1)

91.2

34

60

41

35

24

Pre-infection Many dog bite victims present a day or so after i n j u r y with wounds already infected. In our study, 27.7% of all wound infections were already present at the first visit. These all presented more t h a n 24 hours after the injury; more t h a n h a l f of t h e m presented more t h a n 48 hours after the bite (Table 3).

Age Other studies ~4 have reported an increased incidence of pasturella infection in patients u n d e r 4 years and over 55 years of age. In our study, patients aged 4 years or less had only a 6.25% infection rate; those older t h a n 50, 30%. The average age of the patient with a n infected bite was 33 years; w i t h a n u n i n f e c t e d bite, 24 years. Location Location of injury, with attenda n t differences in blood supply, is obviously important. In a study 13 of 31 b i t e s of the face t r e a t e d w i t h meticulous surgical wound care, no i n f e c t i o n s were found. I n a n o t h e r study, ~° 47% of s u t u r e d u p p e r extremity wounds became infected. In most studies, e x t r e m i t y bites have been in the majority;2,s, is this was the case i n 67% of o u r cases. Twenty-eight percent of these hand and a r m bites became infected, compared to only 4% of facial wounds, 12% of scalp wounds, and 16% of all wounds (Tablel). These differences were significant statistically at the 99% confidence level. Both lacerations and punctures considered separately followed these infection rate variations by anatomical region. 7:3 (M a r) 1978

*Significant at the 99% confidence level.

Type of Wound Other studies have reported t h a t the l a r g e r a n d more extensive the wound, the less the chance of infection, p r e s u m a b l y b e c a u s e s u r g i c a l wound care is better. For example, in one study, 7 48% of p u n c t u r e s became infected, compared to 29% of lacerations a n d no infection in avulsion defects. I n a n o t h e r , a l m o s t h a l f of wounds in p a t i e n t s admitted to the hospital were punctures of the hand. 4 In our study, 22% of p u n c t u r e s were infected, compared to 13% of lacerations r e q u i r i n g one-layer repair, and 6.6% of those r e q u i r i n g two-layer repair. P u n c t u r e s accounted for 40% of all i n f e c t i o n s seen, w h e r e a s deep two-layer lacerations only accounted for 4% (Table 2). Treatment Delays E i g h t y - o n e p e r c e n t of our patierits were seen w i t h i n 24 hours of injury; the infection rate was 8.8% (Table 3). However, patients presenting 24 to 48 hours after injury had an infection rate of 66.6%, 'and those p r e s e n t i n g 48 h o u r s a f t e r i n j u r y , 40%. Thus, 59% of all infections were in cases t h a t presented to the emerg e n c y d e p a r t m e n t m o r e t h a n 24 hours after injury. When cases with pre-existing infection were excluded, 8.8% of those seen w i t h i n 24 hours developed infection, 44% of those i n 24 to 48 hours, and only 10% of those greater t h a n 48 hours. Thus, it is the p a t i e n t p r e s e n t i n g at 24 to 48 hours after inj u r y who is at g r e a t e s t r i s k ' t o de-

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velop infection. This category alone accounted for a third of all infections t h a t developed (rather t h a n pre-existed). The p a t i e n t w i t h p r e - e x i s t i n g infection is a c t u a l l y more likely to present at greater t h a n 48 hours t h a n at 24 to 48 hours after injury. Irrigation Proper wound irrigation has repeatedly been shown to be one of the most effective forms of prophylaxis a g a i n s t infection in all lacerations, reducing infection ten-fold or more. TM In our study, 12% of irrigated wounds d e v e l o p e d i n f e c t i o n , c o m p a r e d to 69% of those not irrigated. The latter, however, were a l m o s t e x c l u s i v e l y p u n c t u r e wounds (Table 4). Debridement A dog's teeth exert up to 400 lbs sq in of force and actually represent more of a crush injury t h a n a clean l a c e r a t i o n . 17 Thus, d e b r i d e m e n t of devitalized tissue is important. This has not been specifically• studied in the l i t e r a t u r e . In our study, 7% of d e b r i d e d w o u n d s b e c a m e infected, c o m p a r e d to 17% of those n o t debrided (Table 5). Suturing The c o n s e n s u s on t h i s subject changes periodically. In recent years opinion has reversed itself and suturing of simple dog bites is considered acceptable.~,7,s, 11 Yet, some sources s t a t e t h a t s u t u r i n g i n c r e a s e s the c h a n c e s of i n f e c t i o n , p a r t i c u l a r l y , t h a t p u n c t u r e s wounds should never 85/13

Table 4 IRRIGATION AND INFECTION RATE* Total No

% Infected

(No)

% of all Infected Cases

All Cases Irrigated

57

12

(7)

46

Not irrigated

22

69

(15)

31

Information not available

23

15

(4)

23

(6)

100

Punctures and Wounds Infected on Arrival Excluded Irrigated

44

Not irrigated

13.6

1

0

0

*Significant at the 99% confidence level.

Table 5 WOUND DEBRIDEMENT AND INFECTION RATE *+

Total No

% Infected 7.1

(No)

% of all Infected Cases

Debrided

14

(1)

7.6

Not debrided

46

17

(8)

61

Not available

34

12

(4)

30

* Wounds infected on arrival excluded. +Significant at the 90% confidence level.

Table 6 SUTURING AND INFECTION RATE *+ Total No

% Infected

All Wounds Sutured

34

2.9

Left open

66

(No)

% of all Infected Cases

(1)

7.6

(17)

26

92

Punctures excluded Sutured

34

Left open

16

2.9 25

(1)

20

(4)

80

* Wounds infected on arrival excluded. +These differences are all significant at the 99% confidence level, 'but the small numbers involved under "punctures excluded" make interpretation hazardous.

be closed for this reason, regardless of l o c a t i o n . 5 I n one m u c h - q u o t e d study 1° 47% of s u t u r e d wounds (even t h o u g h properly excised) became infected. However, t h i s g r o u p of pat i e n t s were all selected on the basis of h a v i n g wounds %hought to be con14/86

t a m i n a t e d " from the first day, and t h e w o u n d i n f e c t i o n r a t e for all groups was much h i g h e r t h a n in the rest of the l i t e r a t u r e - - 29% overall, a n d 30% in f a c i a l w o u n d s in children. In a n o t h e r study, of all p a t i e n t s

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with upper extremity (high-risk) bites severe enough to r e q u i r e hospitalization and all clinically infected on admission, 80% closed p r i m a r i l y h a d positive c u l t u r e s , c o m p a r e d to 30% of those left open, which healed without further complication. 4 These wounds were c o n t a m i n a t e d crush inj u r i e s and punctures, not lacerations. Twenty-four other patients with s i m i l a r wounds were t r e a t e d as outp a t i e n t s with elevation, b u l k y dressings, no a n t i b i o t i c s , a n d no suturing. None developed infection. U n f o r t u n a t e l y , n e i t h e r of the above s t u d i e s , d e a l i n g solely with contaminated or grossly infected cases, helps clarify the optimal t r e a t m e n t of o r d i n a r y wounds. In our study, only 2.9% of s u t u r e d wounds became infected, compared to 25% of those left open (punctures excluded) (Table 6). P r e s u m a b l y , this reflects the b e t t e r surgical toilet of sutured wounds. Such was the a s s u m p t i o n of another study, 7 in which the larger wounds requiring suturing had a lower infection rate. Such a low infection r a t e in s u t u r e d dog bite lacerations is a c t u a l l y superior to that found for simple lacerations in general, s u p p o r t i n g such t r e a t m e n t . 12 Regarding puncture wounds, t h e r e is no study c o m p a r i n g closed and open t r e a t m e n t , except as previously mentioned, where the infection rate was g r e a t l y i n c r e a s e d by suturing. This is p a r t i c u l a r l y true in t h e h a n d , a h i g h - r i s k a r e a , where p u n c t u r e s a r e l i k e l y to p e n e t r a t e several layers of poorly vascularized tissue and tendon spaces. However, some studies have recommended t h a t not even clean lacerations of the h a n d be closed in dog bite.4,17 No good d a t a exist. To t r y to shed l i g h t on t h i s dilemma, our study looked at h a n d wounds excluding all p u n c t u r e s and pre-infected wounds. O n l y t h r e e such w o u n d s w e r e sutured; none b e c a m e infected. Four were not sutured; two of t h e s e bec a m e i n f e c t e d (Table 1). U n f o r t u n a t e l y , t h i s s a m p l e is too s m a l l to draw conclusions. Antibiotics

Prophylactic antibiotics are often r e c o m m e n d e d in p a t i e n t s w i t h dog bite wounds t h o u g h t to be in d a n g e r of infection:5, 2°-22 Yet no good studies exist. In Thomson et al, 7 11% of admitted p a t i e n t s on prophylactic antibiotics developed infections; 29% of such patients with r e p a i r e d l a c e r a t i o n s developed infection. This w a s a t t r i b uted to poor wound toilet. In fact, in t h e i r study, 7 p a t i e n t s w i t h punctures 7:3 (Mar) 1978

N Y A c a d Med 50:981-1000, 1974.

Table 7

3. Scarcella J: Management of bites: early definitive care of bite wounds. Ohio State M e d J 65:25-31, 1969.

INFECTION. RATE AND PROPHYLACTIC ANTIBIOTICS * +

Total No

% Infected

(No)

% of all Infections

Antibiotics

32

12.5

(4)

31

No Antibiotics

65

13.8

(9)

69

* Pre-infected wounds excluded. +The difference between these two groups is not statistically significant.

had 39% i n f e c t i o n w i t h a n t i b i o t i c s and 8% without, lacerations 29% and 0%, and avulsions 50% and 0%. They explained this on the basis of delays of up to 24 hours in both s u r g i c a l t r e a t m e n t and i n s t it u t io n of antibiotics. In a n o t h e r study, 116 patients, mostly with well-debrided facial wounds and all on prophylactic antibiotics, n o n et h el e s s d e m o n s t r a t e d a 6% infection rate. 5 In o u r s t u d y , 32 p a t i e n t s received p r o p h y l a c t i c a n t i b i o t i c s and 65 did not. There was essentially no difference in the infection r a t e between the two groups. All were on p e n i c i l l i n e x c e p t two on o x a c i l l i n : one p a t i e n t w i t h an a r m laceration and one w i t h p r e - i n f e c t e d hand puncture (Table 7). Review of these cases r e v e a l e d no significant difference of severity, type of wound, or other factors b et w e e n the two groups. Had a study been randomized, thus e l i m i n a t i n g any possible bias or sorting by the t r e a t i n g physician, the results m i g h t have been different. Summary On the basis of our study and a review of the literature, we came to the following conclusions 1) R i s k factors. An age of g r e a t e r t h a n 50 y e a r s , p u n c t u r e w o u n d s , hand or a r m wounds, and delay in seeking t r e a t m e n t of 24 to 48 hours all g r eat l y increase the risk of infection. F a c i a l w o u n d s a r e v e r y low risk. 2) W o u n d toilet. D e b r i d e m e n t and a d e q u a t e h i g h - p r e s s u r e i r r ig a tion (at least 150 ml of n o r m a l saline thr o u g h a 19-gauge needle) are crucial to good r e s u l t s . T h e m o r e thorough the preparation, the lower the p r o b a b i l i t y of w o u n d i n f e c t io n will be. 3) S u t u r i n g . Most l a c e r a t i o n s

7"3 (Mar) 1978

m a y be sutured, after good surgical toilet. P u n c t u r e wounds in most locations should not be closed unless they can be excised and thoroughly irrigated. Wounds of the h a n d p r e s e n t a special problem as they are very high r i s k . P u n c t u r e s s h o u l d n e v e r be closed, b u t should be t r e a t e d w i t h thorough cleansing, splinting, b u l k y i m m o b i l i z i n g dressings, and elevation for several days. No data exist on closing simple lacerations of the hand, but if done it should be borne in m i n d t h a t a m u l t i p l e - l a y e r puncture probably u n d er l i es the lacerations. 4) A n t i b i o t i c s . T h e r e is no evidence t h a t p r o p h y l a c t i c a n t i b i o t i c s are of any benefit, but no controlled studies have been done. W h e n infection becomes evident, about h a l f the t i m e it is caused by pasturella, which is very sensitive to p e n i c i l l i n . ' A m o n g the r e m a i n d e r of infections, about 3% to 5% can be expected to be caused by p e n i c i l l i n - r e s i s t a n t st ap h (based on a n i m a l c a r r i e r studies). Thus, over 95% of infecting o r g an i sm s will be sensitive to plain penicillin, but use of a p e n i ci l l i n ase- r esi st an t antibiotic is also logical. 5) C u l t u r e s . C u l t u r e s of u n i n fected wounds are not helpful, since o r g a n i s m s p r e s e n t do not c o r r e l a t e well to s u b s e q u e n t infection. Since penicillin an d staph-effective drugs will be effective on v i r t u a l l y all org a n i s m s , c u l t u r e s an d s e n s i t i v i t i e s should be necessary only in the most stubborn cases. REFERENCES 1. Berzon D, DeHoff J: Medical costs and other aspects of dog bites in Baltimore. Pub Health Rep 89:377-381, 1974. 2. Harris D, Imperata PJ, Oken B: Dog bites - - an unrecognized epidemic. Bull

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4. Chambers G, Payne J: Treatment of dog bite wounds. Minn Med, March 1969, pp 427-430. 5. Schultz R, McMaster W: The treatment of dog bite injuries, especially those of the face. P l a s t R e c o n s t r S u r g 49:494-500, 1972. 6. Harnett DL: Introduction to Statistical Methods. Reading, Massachusetts, Addison-Wesley Publishing Company, 1975. 7. Thomson HG, Svitek V: Small animal bites: the role of primary closure. J Trauma 13:20-23, 1973. 8. Douglas L: Bite wounds. A m F a m Physician 11:93-99, 1975. 9. Tindall J, Harrison C: Pasturella multocida infections following animal injuries, especially cat bites. Arch Dermatol 105:412-416, 1972. 10. Lee JLH, Buhr AJ: Dog bites and local infection with pasturella septica. B r Med J 2:169-171, 1977. 11. Graham W, Calabretta A, Miller S: Dog bites. A m F a m Physician 15:132-137, 1977. 12. Galvin RJ, DeSimon D: Infection rate of simple suturing. J A C E P 5:332-333, 1976. 13. Torphy DE, Ray CG: Pasturella multocida in dog and cat infections. Pediatrics 43:295-297, 1969. 14. Francis D, Holmes M, Brandon G: Pasturella multocida infections after domestic animal bites and scratches. J A M A 233:42-45, 1975. 15. Smith JE: Studies on pasturella septica: III, strains from human beings. J Comp Pathol 69:231-235, 1959. 16. Szalay G, Sommerstein A: Inoculation osteomyelitis secondary to animal bites. Clin Pediatr 11:687-689, 1972. 17. Parks B, Hawkins L, Horner P: Bites of the hand. Rocky M t Med J 71:85-88, 1974. 18. Mayers SP, Beachley RG: A survey of dog bites in Arlington. Va Med 82"317319, 1955. 19. Stevenson T, Thacker JG, Rodeheaver GT, et al: Cleansing the traumatic wound by high pressure irrigation. J A C E P 5:17-21, 1976. 20. Platt FW: Case Studies in Emergency Medicine. Boston, Little Brown & Co, 1974, p 82. 21. Hill G: Outpatient Surgery. Philadelphia, WB Saunders Co, 1973, p 201. 22. Grabb WC, Smith J (eds): Plastic Surgery: A Concise Guide to Clinical Practice. Boston, Little Brown & Co, 1973, p 261.

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