Indian Journal of Pharmacology Medknow Publications on behalf of Indian Pharmacological Society ISSN: 0253-7613 EISSN: 1998-3751 Vol. 39, Num. 2, 2007, pp. 121-122

Indian Journal of Pharmacology, Vol. 39, No. 2, March-April, 2007, pp. 121-122

Research Letter

Prophylactic role of netilmicin in genitourinary surgery

Bajaj Jagminder, Singh SatinderJit, Bedi ParamjitSingh

Sri Guru Ram Das Institute of Medical, Sciences and Research, Amritsar, Punjab
Correspondence Address:Sri Guru Ram Das Institute of Medical, Sciences and Research, Amritsar, Punjab jagminder1@rediffmail.com

Code Number: ph07030

Postoperative infections constitute the largest single group of complications after surgery. The incidence of postoperative wound and urinary tract infections is quite high in genitourinary surgery, primarily because of the contaminated nature of procedures (as many of them involve entry into genitourinary tract in he presence of infected urine) and placement of indwelling urinary catheters. ^[1],[2] This can be reduced by strict adherence to aseptic techniques, shortening of operative time and prophylactic use of antibiotics. Prophylactic antibiotic use has been hotly debated for the last four decades and the search for an ideal prophylactic antimicrobial agent is still in progress. Any prophylactic antimicrobial agent used presumptively should have a high degree of activity against the microbial flora likely to be encountered in a specific surgical procedure. The rationally used regimes for prophylaxis of postoperative infections commonly include ampicillin and gentamicin. With the advent of third generation aminoglycosides, ampicillin and gentamicin are being replaced by these agents, which are being used with increasing frequency as single broad-spectrum agents. Netilmicin, a third generation aminoglycoside, is reported to have a good clinical effect in the prevention of bacterial infections, when administered pre- or postoperatively ^[3] without significant adverse effects. ^[4] The objectives of the present work were (a) to evaluate netilmicin sulphate as a prophylactic antibiotic in genitourinary surgery and (b) to compare its clinical efficacy and safety with ampicillin sodium and gentamicin sulphate.

Fifty patients undergoing elective urinary or genital surgery in the Department of General Surgery, Guru Nanak Dev Hospital / Govt. Medical College, Amritsar (from July 2002 to February 2003, an eight month period) were included in the study. The institute's ethical committee approved the study and informed written consent of the patients was taken. Patients who were> 70 years, diabetic, having renal impairment, hypersensitivity to penicillins and/or aminoglycosides, receiving steroids and those receiving antibiotics one week preceding surgery were excluded. These 50 patients were divided randomly using the 'Random Number Method' into the following two groups (n = 25 for each group):

Group A (Study Group)-received single dose of netilmicin sulphate 300 mg intramuscularly (i.m.), one hour prior to surgery.

Group B (Control Group)-received the first dose of ampicillin sodium 500 mg and of gentamicin sulphate 80 mg i.m. one hour prior to surgery and then, ampicillin sodium 500 mg at 6 -hour intervals and gentamicin sulphate 80 mg i.m. twice a day for 5 days postoperatively. However, as soon as patients were able to take ampicillin sodium orally, injection ampicillin sodium was replaced by capsule ampicillin trihydrate 500 mg every 6 hours.

The wound was inspected on the third postoperative day, after which the wound was kept exposed and observed daily until the removal of stitches. Severity of the wound infection was graded according to Robertson classification, ^[5] i.e., Grade 0-no infection, Grade 1-redness about a stitch, Grade II-pustule about a stitch or minor infection of wound edges without separation, Grade III-frank infection of a relatively small portion of the wound with purulent discharge and some systemic infection and grade IV-frank infection of a large portion of wound with systemic infection. Any complaints of fever, rigors, chills, dysuria or increased frequency of micturition were recorded. Complete urine analysis was done in patients with such symptoms, which are suggestive of urinary tract infection. Urine culture sensitivity testing was done for patients who had a significant number of pus cells (> 5-6/HPF [high power field]). Spontaneously reported side effects were recorded and a checklist of side effects (diarrhea, tinnitus, hearing impairment, vertigo and allergic reactions) was filled.

The mean ages of patients (in years) were 41.40 ± 13.26 in group A and 41.04 ± 13.30 in group B. Student's t-test was used to compare the mean ages of patients in the two groups. It was not statistically significant ( P > 0.05). Incidence of postoperative infections was recorded in the two groups. Standard error of difference between two proportions (S.E.P.) was calculated and the significance of this difference was found by Normal deviate (Z) test. Overall incidence of wound infection in Group A patients, who received netilmicin preoperatively was two in comparison to six in Group B patients who received a combination of ampicillin and gentamicin preoperatively and for five days postoperatively [Table - 1]. This difference in the incidence of infection in the two groups was not statistically significant ( P < 0.10). However, the severity of wound infections was less in the netilmicin-treated group (group A).

In Group A, only two patients developed Grade 1 infection but none of the patients developed Grade II, III or IV infection. Whereas in group B, one patient had Grade I infection, three cases developed Grade II infection and two cases had Grade III infection although no patient developed grade IV infection [Table - 1]. The differences in incidence of Grade I and Grade III infection in Groups A and B were not statistically significant ( P > 0.05) whereas the differences in incidence of Grade II infection in Groups A and B were statistically significant ( P < 0.05). None of the patients receiving netilmicin suffered from urinary tract infection postoperatively in comparison to three patients receiving ampicillin and gentamicin. This difference in incidence of urinary tract infection in the two groups was statistically significant ( P < 0.05).

The occurrence of postoperative wound and urinary tract infections in different procedures is shown in [Table - 2]. The incidence of postoperative infections was observed to be greater in patients undergoing Freyers prostatectomy as compared to those undergoing total abdominal hysterectomy with bilateral salpingo-oopherectomy and pyelolithotomy in both the study and control groups. Only one patient in group B who underwent Hypospadias repair developed a postoperative infection. Thus, 100% incidence obtained is arbitrary. Variety of other genitourinary procedures like oopherectomy, excision of epididymal cyst, ureterolithotomy and Lord's plication were included in the study, but none of the patients in group A or group B undergoing these procedures developed any postoperative infection.

No adverse drug reaction occurred in any patient in group A. In group B, an adverse drug reaction occurred in the form of diarrhea only in one patient (4%). None of the patients in group A or group B developed any tinnitus, hearing impairment, vertigo or allergic reactions. In our study, none of the patients receiving netilmicin suffered from urinary tract infections postoperatively. This is consistent with findings of previous investigators ^[5],[6] who reported netilmicin to be an efficient antibiotic for treatment of UTI. The severity of postoperative wound infections was also found to be less in the netilmicin-treated group as reported by previous investigators. ^[1],[3] Netilmicin was well tolerated as out of 25 patients, none developed any adverse reaction to it, which is in accordance with the opinion of previous investigators. ^[5],[7] Thus, our study indicates that netilmicin given as a single preoperative dose, is a promising (safe and effective) prophylactic drug in genitourinary surgery.

Acknowledgements

References

Copyright 2007 - Indian Journal of Pharmacology

The following images related to this document are available:

Photo images