Comparison of blood loss in total knee replacement surgery with and without tranexamic acid: a prospective, time framed and observational analytical study

Background: Total knee replacement is one of the common orthopaedic procedures performed worldwide. Blood transfusion is one of the major requirements in TKR procedure due to the amount of blood loss during and after the procedure. We carried out a prospective study to determine the efficacy of tranexamic acid in controlling blood loss during TKR procedure. Methods: Study was conducted at a tertiary care centre, involving cases operated by a single surgeon. Study included 140 patients undergoing primary TKR for advance degenerative disease of knee and were divided into two groups of 70 each, one group that received tranexamic acid before surgery and another group that did not receive tranexamic acid before surgery. Patient with allergy to the drug, hepato/renal dysfunction, DVT, abnormal PT and INR were not included. Tranexamic acid was given intravenously as well as intra-articular. Results: Pre-operative haemoglobin ranged from 10.2 gm% to 14.4 gm% in the group getting tranexamic acid and from 10% to 14 % in the group not getting tranexamic acid. Post operatively haemoglobin varied from 8.4 gm% to 12.8 gm% in Group 1 and from 7.8 gm% to 12 gm% in Group 2. Difference of mean post-operative Hb (p=0.0045) and PCV (p=0.0024) in two groups was statistically significant. Conclusions: We concluded that administration of tranexamic acid reduces the blood loss as well as need of blood transfusion in a patient undergoing total knee replacement.

A clinicobacteriological study on leucorrhoea.

The pathogens like Trichomonas vaginalis (4.5%), N gonorrhoeae (2.7%) and C albicans (6.7%) were exclusively present in leucorrhoea. The other potential agents with their respective percentages in normal women and cases of leucorrhoea were U urealyticum (21.2% and 50.2%), actinomyces (29.7% and 41.6%), Chlamydia trachomatis (17% and 48.8%), candida-like organisms (CLO) (1.2% and 9.5%) and non-group B streptococci (4.2% and 16.7%). The percentages of urethral syndrome (65.8%), vaginal irritation (63.4%), sore vulva (17%), cervicitis (13.4%), cervical erosion (11%) of the STD clinic were more than those of gynaecological cases. The latter group more often revealed infertility (15.8%) and pelvic inflammatory disease (13.6%). The exclusive isolation rate of N gonorrhoeae (7.3%) and prevalence of G vaginalis (19.5%) and Trichomonas vaginalis (8.5%) in the STD clinic were notable. The cases of gynaecological clinic more commonly showed C albicans (8%) and CLO (13.6%). Significant differences pertaining to U urealyticum (leucorrhoea and inapparent group p < 0.01; leucorrhoea and normal cases p < 0.01), M hominis (leucorrhoea and inapparent group p < 0.05; leucorrhoea and normal cases p < 0.01), Chlamydia trachomatis (leucorrhoea and normal cases p < 0.01) and also actinomyces (leucorrhoea and normal cases p < 0.01; inapparent and normal cases p < 0.05) were recorded. There was conspicuous association of U urealyticum, M hominis, G vaginalis, Chlamydia trachomatis, CLO and actinomyces with leucorrhoea. An almost exclusive presence of Staph aureus, Esch coli and Klebsiella in cases of leucorrhoea appeared meaningful.

Pathogenic potential of Gardnerella vaginalis on the female urogenital system.

The prevalence of certain characteristics of genital discharge like (a) watery variety in sexually transmitted disease (STD) clinic 34% and in gynaecology clinic 26.6%, (b) fishy odour in STD clinic 29.2% and in gynaecology clinic 12.2% and (c) pH > 4.5 in STD clinic 53.6% and in gynaecology clinic 43% was notable. On the other hand, occurrence of "clue cells" (in STD clinic 41.4% and in gynaecology clinic 39.5%) did not show difference in the aforesaid clinics. The preponderance of watery discharge in the STD clinic appears to be related to G vaginalis (in STD clinic 26.8% and in gynaecology clinic 9.3%). It is intriguing to note that G vaginalis was isolated from leucorrhoea (in STD clinic 19.5% and in gynaecology clinic 9.3%) and inapparent (in 10%) cases and normal (in 4.2%) cases. Single infection with G vaginalis in one particular case had profuse watery discharge, pH > 4.5 and there was occurrence of "clue cells". Likewise, in multiple infections revealing G vaginalis (29 cases) as one of the potential agents, 78.5% had profuse, 53.8% watery discharge of which 53.5% had "clue cells" and 81% had pH > 4.5. In mixed type of infections, the U urealyticum (53.8%) and M hominis (30.6%) were conspicuous in bacterial vaginosis. Cervicitis, erosion cervix or urethral syndrome were unrelated to G vaginalis. All cases of G vaginalis infection responded to metronidazole with remission of leucorrhoea in 25.9% cases.

Non-sporing anaerobes in certain surgical group of patients.

The magnitude of non-sparing anaerobic (NSA) infections has been defined in the postoperative wounds on colorectum in children (57.1%), general surgery (0%), abdominoperineal and uterocervical operations (11-45%) in gynaecologic and obstetrical cases and perforative peritonitis (25.8-32.3%). Children below the 6 months age group bear less risk of acquiring NSA infection. Under certain situations, metronidazole combats NSA infections in a better way than other antibacterials. The bacteriology of NSA infections has been probed at the species level in the gynaecologic and obstetrical patients. The species of normal cervix (44.6%) are represented in wounds involving abdominal wall (11%), perineum (22.8%) and uterocervix (45.6%) to suggest endogenous infection. Out of the 22 species of NSA isolated, Peptostreptococcus anaerobius, Acidaminococcus fermentans and Peptococcus prevotii are the commonest. Others were Peptococcus niger, Gaffkya anaerobia, Lactobacillus bulgaricus, Actinomyces bovis, Bacteroides oralis, Fusobacterium gonidiaformans and the different species of peptococcus, peptostreptococcus, eubacterium, propionibacterium and fusobacterium. The weight of evidence indicated a pathogenic role of Peptostreptococcus anaerobius and Ruminococcus flavefaciens, in view of their heavy growth. The umbrella of antibacterials reduced Gram-positive anaerobic cocci from 40% to 16%. The facultative anaerobes Staph aureus, Staph epidermidis, Kl pneumoniae and proteus appeared as the exogenous agents of nosocomial infections.

Bacteria in surface infections of neonates.

A bacteriological work on surface infections was done among live births (study group I) and neonates admitted in hospital (study group II). Out of 134 cases of conjunctivitis in group I Gram-negative bacilli predominated (48.5%) with Escherichia coli accounting for 29 (14.9%) cases, Klebsiella species 15 (11.2%) cases, Citrobacter freundii 3 (2.2%) cases, Pseudomons aeruginosa 18 (13.4%) cases and Aeromonas hydrophila 3 (2.2%) amongst pure isolates (73.9%). Gonococcus was noted in 2 (1.5%) cases. In group II, 41.7% were Staphylococcus aureus in pure growth (75%), compared to only 9.0% in group I. Skin infections were caused by both Staphylococcus aureus and Staphylococcus epidermidis. Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were the principal insolates from umbilical sepsis. Pseudomonas aeruginosa was isolated as pure growth from local site of noma neonatorum. Anaerobic cultures were negative in all except in 2 cases of umbilical sepsis with tetanus neonatorum revealing Clostridium tetani which however proved to be non-toxigenic. Blood cultures were positive in 4 out of 14 cases bearing 50% correlation with bacteria from surface infections. A source study established partial correlation with the cases of pseudomonas conjunctivitis. Phage typing of Staphylococcus aureus and biochemical typing failed to detect any definite marker of clinical entities, except that the skin infections were caused by group III phages predominantly (65.0%).

Rapid diagnosis of anaerobic gram-positive cocci by salt tolerance.

The maximum salt tolerance was 2.5% in cases of Peptostreptococcus anaerobius and Peptococcus prevotii, 3% in Ruminococcus albus, 4% in Acidaminococcus fermentans, Peptococcus niger and Megasphaera elsdenii and 5% in Peptococcus magnus. The biochemical tests being largely inactive and time consuming the findings of salt tolerance if combined with those of morphological data provide clue to the rapid identification of Gram-positive anaerobic cocci.

Microflora in postirradiated cancer cervix.

Cases of cancer cervix receiving radiation therapy revealed more anaerobes (50%) in comparison to normal controls (44.6%). The aerobic organisms were suppressed in the former cases (63.6%) in contrast to the latter group (90.7%). Of the anaerobes, the Gram-negative bacilli were more notable (18.1%) in cancer cervix than the normal controls (4.6%). The anaerobes like Peptococcus prevotii (18.1%) and Bacteroides oralis (9%) and the aerobes, Staph aureus (13.6%) and klebsiella (13.6%) were prevalent in cancer cervix. The higher incidence of aerobic and anaerobic organisms in stage III elderly (> 45 years) patients of cancer cervix may necessitate antibacterial therapy.

Numerical taxonomy of vibrio & allied organisms.

Forty four strains of Vibrio, Pasteurella, Yersinia, Aeromonas, Escherichia, Klebsiella and Enterobacter were tested for 44 characters and the overall results scored by the procedure of numerical taxonomy. The strains were clustered by the weighted pair group method with the arithmatic averaging. The V. cholerae 01 and the non-01 V. cholerae being interlinked at a very high level (86% to 97.5%) within a single cluster were considered under the same species. V.cholerae having Classic, E1 Tor and Gindha (Pfeiffer 1896, as per priority) biotypes respectively. The biotypes of V.parahaemolyticus remained clearly delineated from Vibrio and Aeromonas, and, belonged to a new separate genus. The V. parahaemolyticus biotypes were located more adjacent to Yersinia and Pasteurella than the V. cholerae cluster. V.fluvialis 1 appears as a biotype of V.parahaemolyticus, and, not a new species.

Non-sporing anaerobes in hospital sepsis.

In comparison to normal controls, the non-sporing anaerobes were often isolated from orodental sepsis (42% to 44.4%), chronic suppurative otitis media (40%), septic abortion (40.3%), uterocervical wound (45.4%), vaginitis (50%) and cancer cervix (50%). This was true (40%) in perforating ulcers of foot in leprosy. These organisms were less frequently noted in abdominal (11%) and episiotomy (22.8%) wounds and leucorrhoea (33.3%). The role of non-sporing anaerobes was also suggested by the high percentage ratio of number of isolates to number of cases and by its primary isolation in moderate to heavy number. Barring the cases of cancer cervix, the aerobic bacteria were the most common (78.8% to 100%) in all other conditions.

Antibacterial susceptibility of anaerobes by agar dilution method.

Of the 9 antibacterials, vancomycin alone at its break-point (optimum blood level) revealed highest (93.3%) efficacy on Gram-positive cocci. The remarkable activity of carbenicillin, chloramphenicol and vancomycin on Gram-positive cocci (95.4 to 96.9%), carbenicillin and chloramphenicol on Gram-positive bacilli (94.8% to 98.2%) and chloramphenicol on Gram-negative bacilli (95.4%) was noted by increasing their concentrations 1.5 to 2.5 times above their break-points. These (and even higher) concentration, however, showed relatively lower efficacy of metronidazole, rifampicin, penicillin, clindamycin and erythromycin on Gram-positive cocci (76 to 84.1%), rifampicin, tetracycline, erythromycin, clindamycin and vancomycin on Gram-positive bacilli (81 to 87.9%) and clindamycin, metronidazole, rifampicin and carbenicillin in Gram-negative bacilli (72.7 to 84%). By and large, rifampicin, chloramphenicol and carbenicillin are also quite effective (72.1 to 75.1%) at lower concentration.

Clinicobacteriological study of empyema thoracis in infants and children.

Forty-one cases of empyema thoracis admitted in hospital during April, 1985 to August, 1987 were studied. Majority were males (65.9%) and were of less than 2 years of age (70.7%). Right side (60.9%) was predominantly involved. Abdominal distension (43.9%) was very characteristic, with other usual features like fever, cough and respiratory distress. A large majority of them were victims of malnutrition (73.2%) and anaemia (53.7%) with haemoglobin level ranging from 5-9 g/dl. Mortality was high (17.1%). Therapy with parenteral cloxacillin and gentamicin and continuous intercostal tube drainage accounted for loss of 15.8 bed days (average period of hospitalisation). Staph aureus was the principal aetiopathogen (68.3%). No anaerobe could be isolated. Strains of staphylococci were mostly resistant to penicillin and ampicillin but sensitive to gentamicin, cloxacillin and erythromycin.

Sensitivity of the different tests of enterotoxigenicity of Escherichia coli and their correlation.

Enterotoxigenicity of E. coli isolates was tested in 136 cases of acute gastroenteritis. Heat labile toxin (LT) produced in-vitro was tested in rabbit ileal loop (RIL); vero cell line and Biktn plate. The results of live cultures were evaluated in RIL. The overall data of these four models were not statistically different. Elaboration of LT in these four models ranged from 14-21.4%. Out of the 20 LT producing strains 14 (70%) also revealed ST. Of the 6 positive reactors on vero cell line, appeared to produce vero toxin (VT) only. Out of 29 LT positive E. coli, 1 (3.45%) and 2 (6.89%) strains respectively revealed colonising factor antigen (CFA) I and II. The high incidence of ETEC showing both LT and ST has been highlighted in the age group 0-4 years, and its impact on nutritional status is discussed.

Etiology of acute childhood diarrhoea in Calcutta.

Of the 152 cases of acute diarrhoea, 124 (81.5%) revealed potential pathogens. Altogether 27 (21.2%) out of 127 strains of Escherichia coli, Klebsiella pneumoniae, Enterobacter, Proteus and Acinetobacter produced enterotoxin. Single pathogenic bacteria (40 cases 26.3%), parasite (6; 6%), rota virus (6; 6%), toxigenic bacteria (19; 12.5%) and mixed agents (37; 24.24.3%) were recorded in 108 cases (71.0%). Another 14 (9.2%) cases exclusively revealed moderate to heavy growth of suspected enteric pathogens like K. pneumoniae, Proteus, Enterobacter, Pseudomonas aeruginosa, anaerogenic E. coli and Citrobacter and 2 (1.3%) had high counts of T'. hominis. Of the known pathogens, the preponderance of A. hydrophila (24.4%), rota virus (15.7%) and Aeromonas hydrophila (14.0%) in 1-4 y, Vibrio cholerae (45.6%) and Trichuris trichiura (13.0%) in 4-14 y age group is highlighted. Other pathogenic bacteria were non-01 V. cholerae (3.2%), V. parahaemolyticus (2.6%), V. fluvialis (0.6), Plesiomonas shigelloides (3.9%), Salmonella (2.6%), Shigella (1.9%), EPEC (1.9%), EEC (5.2%) and Campylobacter jejuni (3.9%) and the parasites were Entamoeba histolytica (2.6%) and Giardia intestinalis (2.6). Comparative study of age matched controls with those of diarrhoea suggested the pathogenic role of E. histolytica and T. hominis.

Ischaemic mouse thigh model for evaluation of pathogenicity of non-clostridial anaerobes.

A mouse thigh model has been devised in which the growing culture of non-clostridial anaerobe in the ischaemic tissue produces inflammatory swelling and death. The swelling of the right thigh served as an index of pathogenicity of the test strain in comparison to the negatively reacting left thigh which received injection of the control strain of Bifidobacterium infantis. Actinomyces naeslundii exceptionally caused death in all animals within 24 h. Mortality and thigh swelling were pronounced (greater than 75%) in case of Fusobacterium gonidiaformans and Propionibacterium acnes but less (less than 50%) in Acidaminococcus fermentans. High (less than 75%) rate of thigh swelling was also encountered in case of Bacteroides oralis, Bacteroides corrodens, Fusobacterium necrophorum, Fusobacterium prausnitzii, Fusobacterium plauti, Peptococcus prevotii, Streptococcus intermedius, Eubacterium lentum and Propionibacterium freudenreichii ss. shermanii.