Management of necrotizing tracheostomy infections

Management of three patients with necrotizing tracheostomy infections resulting in tracheal dissolution was reviewed with respect to presentation, cause, and management. Loss of tracheal substance led to difficulty in ventilation because of a large air leak. The stomal area cavitated in two patients, denuding the right common carotid artery in one. Purulent peristomal drainage was present in all three patients. Common factors of possible etiologic significance included necrotizing polymicrobial gram-negative tracheobronchial infections caused by Pseudomonas, Enterobacter, and Klebsiella species. Also of possible importance were suture fixation of the appliance, history of neurologic injury, and closure of the incision. Immediate therapy consisted of oral intubation for ventilatory purposes and a regimen of hourly application of 1% neomycin dressings. Seven to 21 days were necessary to allow formation of sufficient granulation tissue to support replacement of the tracheostomy appliance for continued mechanical ventilation. Once spontaneous ventilation was possible, a Montgomery T-tube was inserted for long-term tracheal stenting prior to reconstruction. The two patients treated by tracheal stenting are long-term survivors. Avoidance of suture fixation of the appliance, aggressive treatment of bronchopulmonary infection, and adequate stomal toilet may help to avoid this devastating complication.

[Antibiotic preparation in operations on the large intestine. Experimental study]

A controlled study was mounted to assess the possible benefit of a single phlebo administration of 600 mg lincomycin 1 hr prior to colon surgery, in addition to the erythromycin + neomycin combination proposed by Nichols, as a means of constituting a further pharmacological barrier to the spread of anaerobic bacteria. The study currently comprises two groups of 15 patients fully comparable with regard to pathology distribution and randomly assigned to the E.N. and the E.N.L. protocol respectively. Six instances of septic complication have been observed, five in the group prepared with E.N. and 1 prepared with E.N.L. No significance can be attached to the different incidence of complications in the two arms of the study, owing to the small number of cases examined.

Bowel preparation and the safety of colonoscopic polypectomy

A fatal colonic explosion has been recorded during colonoscopic polypectomy after oral mannitol bowel preparation. It has been suggested that bacterial degradation of oral mannitol allows the production of hydrogen and methane which are potentially explosive. We have analyzed the gas composition of colonic aspirates in unprepared patients (n = 11), after orthograde saline lavage (n = 11), after oral mannitol alone (n = 11), and when oral mannitol was given with oral antibiotics (n = 11). After oral mannitol bowel preparation 7 patients had potentially explosive gas mixtures compared with 4 in the unprepared group, 1 after orthograde saline lavage, and none when oral antibiotics were used before mannitol. We believe, therefore, that if oral mannitol is used for bowel preparation before colonoscopic polypectomy oral antibiotics should also be administered or insufflation should be with carbon dioxide.

A comparative study of polyantibiotic and iodophor ointments in prevention of vascular catheter-related infection

Using a semiquantitative technique for culturing material from vascular catheters, we studied by random allocation the efficacy of three regimens for site care of 827 catheters used in adult patients: an iodophor ointment (PI2), ointment containing polymyxin, neomycin and bacitracin (PNB), and use of no topical agent whatsoever (control). Even though this is the largest study of this subject, there was not a sufficient number of catheter-related septicemias to permit valid comparisons (two in each group, 0.7 percent). However, the rate of local catheter-related infection (greater than or equal to 15 CFU on semiquantitative culture), the prelude to related septicemia, was significantly lower in the PNB group (2.2 percent, P = 0.02) as compared with controls (6.5 percent). Use of PI2-treated catheters resulted in one-half fewer infections (3.6 percent) than use of control catheters (P = NS). Staphylococcal infections occurred with 15 control catheters, eight treated with PI2 and two with PNB (P = 0.002). Infections by gram-negative bacilli occurred less frequently in both treatment groups than in controls, but three of four Candida infections, including one septicemia, occurred in the PNB group. Topical antimicrobial agents confer modest benefit in protection against catheter-related infection, primarily for peripheral venous catheters that must remain in place for more than four days. If an ointment is to be used, topical PNB may be preferable for peripheral venous catheters and PI2 ointment for central venous catheters used for parenteral nutrition and for arterial catheters.

Neomycin-induced neuromuscular blockade

The unusual complication of neuromuscular blockade secondary to neomycin absorption is described. The syndrome characterized by acute muscle flaccidity, diaphragmatic breathing, and central nervous system depression presents a potentially fatal situation. Appropriate treatment of this complication includes respiratory assistance and calcium gluconate administration (IV). A review of the pediatric literature reveals 12 previous cases, of which 2 were secondary to urologic procedures.

Prospective clinical trial of antibiotics for pulmonary resections

One hundred and seventy-one patients undergoing pulmonary resection were included in a prospective randomized clinical study evaluating the efficacy of prophylactic antibiotics. Eight-three patients randomly chosen received no parenteral antibiotics and 88 received a short course of cephalothin intravenously. Topical antibiotics were used in the pleural cavity and would of all patients. There were no statistically significant differences between the two groups in terms of days of postoperative fever, number of postoperative septic complications and length of postoperative stay. However, when postoperative infectious complications developed in the antibiotic group, they were often secondary to gram-negative organisms resistant to cephalothin.

Neomycin toxicosis in calves

Calves (n = 4) were given neomycin (2.25 or 4.5 mg/kg) twice daily IM and were compared with 2 calves given penicillin IM. The 2 hallmarks of aminoglycoside toxicosis, nephrotoxicosis and ototoxicosis, were seen with both dosages of parenterally administered neomycin. Nephrotoxicosis was confirmed by abnormal findings in urinalysis (granular casts, proteinuria, low specific gravity), renal biopsy results (tubular degeneration and necrosis), and increased 24-hour amounts of urinary enzymes (alanine aminopeptidase and gamma-glutamyltranspeptidase). Azotemia, decreased creatinine clearance, polyuria, and polydipsia also were documented in calves given neomycin. Clinically, deafness was suspected in 2 calves and was documented by electrical auditory-evoked response tests. Abnormalities in partial thromboplastin times and renal residues of neomycin were seen in all 4 calves that were given neomycin, but not in calves that were given penicillin.

Treatment of chronic portal-systemic encephalopathy with lactose in lactase-deficient patients

A controlled cross-over clinical comparison of lactose (50 g twice a day) versus neomycin (3 g/day) plus milk of magnesia, was carried out in ten cirrhotic patients with chronic portal-systemic encephalopathy and documented lactase deficiency. Serial semiquantitative assessments were done including: mental state, asterixis, number connection test, electroencephalogram, and blood ammonia levels. No patient developed deep coma while ingesting either lactose or neomycin plus milk of magnesia. However, a significant improvement of mental state, asterixis, number connection tests, and electroencephalograms was evident during lactose therapy. apart from mild diarrhea and bloating, no severe side effects were noticeable during lactose treatment. Based on these results, we propose lactose as a valuable alternate treatment of portal-systemic encephalopathy in lactase-deficient populations.

[Neomycin versus plus metronidazol for large bowel preparation in elective colon surgery]

Two series of 50 consecutive elective colonic resections with bowel preparation either with Neomycin (group A) or Neomycin combined with Metronidazole (group B) are presented. 17 bacterial inflammatory complications in group A versus 10 in group B were noted. It is concluded that the addition of an antianaerobic antibiotic agent in elective colonic surgery might be of beneficial effect.

Bacterial flora in relation to cataract extraction. V. Effects of topical antibiotics on the preoperative conjunctival flora

In a randomized study comprising 60 patients, six different prophylactic regimens were evaluated for their effectiveness in eradicating bacteria on the conjunctivas before surgery. Gentamicin sulfate ophthalmic solution was the only antibiotic able to eliminate bacteria in almost all of the examined patients. The other drugs (chloramphenicol solution, oxytetracycline-polymyxin B ointment, sulphamethizole, bacitracin-neomycin and ristocetin-polymyxin B solutions) were not effective, although most of the isolated strains were sensitive to the respective antibiotics, probably because of the short treatment period (18 h). The problem of prophylactic therapy of ophthalmology is discussed, and some guide lines are given.

Use of a topical triple-antibiotic spray to reduce morbidity from pelvic infection after gynecologic operations

To study the effect of a topical antibiotic spray in reducing postoperative morbidity when used during surgery, a randomized, double-blind study was done on 150 women who had a vaginal hysterectomy with or without colporrhaphy. The spray contained neomycin sulfate, polymyxin B sulfate and zinc bacitracin and was used in 75 patients; a placebo spray was used in the other 75 patients. The antibiotic spray significantly (P < 0.01) decreased the frequency of pelvic infections postoperatively--14.7% in the antibiotic group compared with 37.3% in the placebo group.

Topically administered corticosteroids: effect on antibiotic-treated bacterial keratitis

The effect of a topically administered corticosteroid, 1.0% prednisolone acetate, on bacterial replication in rabbit cornea receiving adequate antibiotic therapy was determined. Staphylococcus aureus keratitis was treated either with neomycin sulfate or gentamicin sulfate, while Pseudomonas aeruginosa keratitis was treated either with gentamicin or polymyxin B sulfate. Each antibiotic was administered topically at hourly intervals in both the commercially available concentration and as a formulation containing four times the quantity of drug found in the commercial preparations. In each instance, the antibiotic regimen sharply reduced the number of viable organisms in the cornea, although the concentrated preparations did so more rapidly and effectively. The addition of 1.0% prednisolone acetate had no measurable effect on outcome. In no instance was there a statistically significant difference between number of residual viable organisms in antibiotic-treated corneas and antibiotic/corticosteroid-treated corneas.

The dose at which neomycin and polymyxin B can be applied for selective decontamination of the digestive tract in mice

Oral treatment of mice with various doses of neomycin or polymyxin B was performed in order to determine which dose caused substantial suppression of aerobic gram-negative rods. In addition the effect of the various doses on Streptococcus faecalis and on other factors of the colonization resistance (CR) of the digestive tract were studied. It was found that polymyxin B was effective in suppressing sensitive gram-negative bacteria following daily doses of 3.2 mg/mouse, and that even extremely high daily doses of 9.7 mg/mouse did not affect the CR. Neomycin was effective in suppressing Enterobacteriaceae species following oral daily doses of 5.4 mg/mouse. With this dose, however, the CR was somewhat decreased which was also evidenced by the increased concentration of beta-aspartylglycine in the faeces and the increased size (weight) of the caecum in these animals. Suppression of Str. faecalis was seen from doses of 24 mg/mouse on.

Combined therapy of Salmonella infection in chickens by antimicrobial agents followed by cultured cecal bacteria

Week-old chickens infected with Salmonella infantis when one day old were treated with antimicrobial drugs either given alone or followed by peroral inoculation of bacterial culture. The bacteria were derived from the cecal contents of adult chickens. The antimicrobial drugs used were: neomycin, neomycin plus oxytetracycline, neomycin plus polymyxin, and sulfadiazine plus trimethoprim. The combined therapy with oxytetracycline plus neomycin and bacterial culture seemed to be the most effective, although the efficacy varied between the parallel trials. Sulfadiazine plus trimethoprim followed by treatment with the bacterial culture decreased the infection rate. The bacterial culture alone also had a slight anti-salmonella effect. When only antimicrobials were given, salmonellae rapidly reappeared in the intestines when the therapy was stopped.

[Therapeutic effectiveness of neomycin in staphylococcal and Pseudomonas aeruginosa corneal lesions]

Ophthalmic films (OPHF) with neomycin were used in treatment of 15 patients with staphylococcal infections of the cornea. OPHF were effective in treatment of 5 patients with affection of the cornea surface layers. These patients were discharged from the hospital on days 4-5 of the treatment. In the other 10 patients deeper layers of the cornea were affected by the infiltrates and their treatment with OPHF required longer periods (10-15 days). Another 5 patients developed severe keratitis caused by Ps. aeruginosa after removal of foreign bodies from the eyes. These patients were treated with neomycin injections, electrophoresis and OPHF. When the patients received such treatment within the first days of the disease (3 patients), the development of the cornea purulent infection ceased and a favourable therapeutic effect was attained. When neomycin was administered at later periods (2 patients), i.e. 3-4 days after the infection, the treatment was not efffective. It is recommended that broad spectrum antibiotics be used for prevention of the cornea staphylococcal infections after removal of foreign bodies from the cornea surface.

Contact allergy following administration of eyedrops and eye ointments

Thirty-five ophthalmological patients with symptoms of contact allergy due to external eye medication were examined with patch tests in the dermatological outpatient department. Attention is paid to sensitization due to antibiotics, in particular Neomycin.

[Nebacetin and taurolin as intraoperative disinfectant solutions in surgery of the locomotor system (author's transl)]

The anti-infective preventive action of intraoperative disinfection with physiological solution containing antibiotics, appears to be firmly established, judging from numerous publications. Since germs are showing a world-wide increasing resistance, the search for antibiotics which continue to be effective must be kept up, but alternative suggestions are equally necessary. Some publications have already been presented indicating that success similar to that previously obtained with antibiotics is possible by using disinfectants in the prophylaxis and treatment of infections. Hence, a comparative study was conducted using the non-absorbable broad-spectrum antibiotic Nebacetin and the disinfectant Taurolin in a 1% solution with a group of patients subjected to a total of 7699 major and minor surgical operations. Prospectively, early infections during the stay of the patient in the hospital, als well as disturbed wound healing, were included. No significant difference was found in the number of infections and the rate of disturbed wound healing. Indirectly, it is possible to conclude with the help of results from literature that the disinfectant Taurolin is suitable as an addition to intra-operative rinsing in the prophylaxis of infections.