RISK FACTORS AND MICROBIOLOGICAL PATTERN OF POST CAESAREAN WOUND INFECTION IN FEDERAL MEDICAL CENTRE OWERRI

(17) risk factors studied were found to be independent variables for post caesarean wound infection. Conclusion: The study showed conclusively that prolonged rupture of membranes, post-operative anaemia and a midline sub-umbilical incision were independent risk factors contributing directly to a higher incidence of post-caesarean wound infection with Staphylococcus aureus being the single most common organism implicated.


INTRODUCTION
Post operative wound infections remains a significant cause of maternal morbidity and mortality Maternal mortality after caesarean section has been estimated to be between 5.8 to 6.1/100,000 procedures .About 20-50% of these death results from the anaesthetic complications of the caesarean section and the remaining being the result of the complications of the etiology for the procedure .In general, obstetric infections account for more than 12% cause of maternal death.
Caesarean section has similar complications to other cases involving laparotomy except for endomyometritis .Those complications include wound infection, thromboembolism, and damage to contiguous structures (Bladder 0.3%, Ureters 0.1%, and Bowel 0.1%) The rate of post caesarean wound infection  showed that post caesarean wound infection was not only the leading cause of prolonged hospital stay but also a major cause of widespread aversion to caesarean section in the region .In addition, obstetric infections result in increased health costs related to prolonged hospital stay, re-admission and the use of oral and parenteral antibiotics .
Recovery from caesarean section is more difficult for women who develop postoperative wound infection .Maternal morbidity related to infection after caesarean section was found to be higher than that of vaginal delivery .Developing infection at the surgical site depends on the interaction between different risk factors which include patient's characteristics like age, parity, maternal weight and gestational age, pre-operative conditions, intra-operative circumstances and post-operative wound management.Some medical conditions which are associated with increased risk of wound infection include diabetes mellitus, sickle cell anaemia, obesity and anaemia.
Other risk factors include patients on prolonged corticosteroid therapy, l o w s o c i o e c o n o m i c s t a t u s , immunosuppresion and abdominal wall haematoma .The preoperative conditions which could predispose to post caesarean wound infection include prolonged rupture of membranes, multiple vaginal examinations during labour, amnionitis, previous meconium passage and internal foetal monitoring during labour.
The intraoperative risk factors include inappropriate operating room environment (air, ventilation, sterilization of the surgical instruments), inadequate scrub, caps, shoe covers, masks,

AIMSAND OBJECTIVES
The specific objectives were:

STUDY DESIGN:
STUDY SETTING: The subjects of the study were recruited from pregnant women who had emergency caesarean section and an equal number of pregnant women who had elective caesarean section.

Inclusion criteria
All pregnant women in labour scheduled for emergency caesarean section or pregnant women for elective caesarean section without the exclusion criteria below.Pregnant women who consented to the study.

Exclusion criteria
The following pregnant women were excluded: a) Women who refused to give consent for the study.
b) Women who did not receive our routine antibiotics according to the protocol.
SURGICAL PROCEDURE: Immediately before the antiseptic preparation of the surgical site, the abdominal skins were shaved.Caesarean section was performed by senior obstetric residents or the consultant when necessary.A Pfannenstiel incision was used on the patients except for those with previous midline incisions in who repeat caesarean sections were indicated.The same scalpel was used for skin and subcutaneous tissue incision.
Transverse lower segment caesarean sections were performed according to standard approach.placenta was delivered by controlled cord traction, however manual removal was done when controlled cord The traction is not possible.The uterus was closed in two layers using polyglactin (Vicryl) suture size two, followed by polyglactin suture size 2-0 for peritoneal layers.The rectus sheet was closed continuously using Nylon suture size 2 and plain catgut suture size 2-0 was used for closure of the subcutaneous layer.Pfannenstiel skin incisions were closed with subcuticular stitches using vicryl 2-0 or interrupted stitches using Nylon 2-0, and the latter also for vertical skin incisions.All the patients received post operative antibiotics according to the departmental protocol viz; intravenous Metronidazole 500mg 8hourly and intravenous Ceftriaxone 1gram daily all for 48 hours.This was followed by tablets Metronidazole 400mg 8hourly and tablets Cefuroxime 500mg 12 hourly for five days.
Wounds were examined on the 3 postoperative day and 5 post-operative day for pfannenstiel incisions and on the 7 postoperative day for midline sub-umbilical incisions for any evidence of infection.Wound infection was diagnosed when a wound discharged purulent material or serosanguinous fluid, presence of induration, erythema, warmth and tenderness in the presence or absence of fever.Those with features of infection had wound swab taken.Inoculation of the culture plate was done on the patient's bedside immediately after collection.The wound swab specimen was coded and numbered consecutively by the researcher in such a way that the designated laboratory scientist (microbiologist) analyzing the specimen did not know at any time which of the specimen was from a patient that will have emergency or elective caesarean section.The test result was kept sealed and the codes broken by the researcher only after the samples have been analyzed by the laboratory scientist.The wound was dressed thereafter with Eusol once or twice daily till discharge depending on the degree of infection.
ANALYSIS OF DATA: At the end of the laboratory work, the data was processed and analyzed using the computer Software Caesarean sections continue to be a component part of achieving safe delivery of the fetus.It is however notoriously fraught with a lot of dangers.One of these is post operative wound infection.This study has critically taken a look at the incidence of this menace, the risk factors predisposing to post caesarean section wound infection and the microbiological pattern.A total of 276 cases were studied with 138 elective and 138 emergency cases.
The overall incidence of post caesarean wound infection was 13.4%.An incidence of 9.4% was found in the elective group and 17.4% in the emergency group.This result agrees with the findings of Hassan       The study highlights the possible aetiology of post-caesarean wound infection.It was evident that prolonged rupture of membranes, post operative anaemia and midline sub umbilical incision were independent variables contributing directly to a higher rate of post caesarean wound infection Staphylococcus aureus was found as the most common aerobe causing wound infection.
The major strengths of this study were the inclusion of a very large number of potential risk factors for post caesarean wound infection and the use of multivariate analysis.The use of microbiology to confirm wound infection in our patients was also remarkable.
Though surgical care is very important to prevent wound infection, some pre and post operative steps could reduce post operative wound infections.Avoidance of prolonged labour by public enlightenment, free antenatal and delivery services and the use of partograph and the use potent antibiotics in cases of rupture of membrane would reduce the incidence of post-caesarean wound infection in our environment.The use of Pfannenstiel incision instead of a midline sub umbilical incision will also reduce the infection rate.Optimizing the patient' haemoglobin concentration especially post operatively is also important.The ability to diagnose promptly wound infections and instituting appropriate intervention to control 30,,8

CONCLUSION AND RECOMMENDATIONS
the situation prevents further progression to overwhelming septicaemia which might have a fatal outcome.

Ibom
Medical Journal Vol.11 No.1 February, 2018 Science (SPSS) version 20. (IBM SPSS statistics 20) Pearson's Chi square test was used to compare the susceptibility of patients that had emergency or elective caesarean sections to wound infections.Multiple logistic regression was used to identify factors that are independently associated with an increased risk of post caesarean wound infection.P-value <0.05 at 95% confidence interval was considered statistically significant.

TABLE 4 : MICROBIOLOGICAL PATTERN OF POST CAESAREAN WOUND IN FEDERAL MEDICAL CENTRE OWERRI
The fact that one woman among the emergency group had clinical evidence of wound infection but negative culture might be attributed to the antibiotics they were 29 taking.Staphylococcus aureus was the predominant organism isolated and this finding was comparable with findings of Kaplan et al and Jido et al .This finding was in contrast with the finding of Vermillion et al where enterococcus species was the predominant organism.It has been postulated that post caesarean wound infection may be derived from the microbial flora of the lower genital tract and this may occur during manual extraction of the fetal presenting part from the lower uterine segment which further facilitates the contamination of uterine cavity by vaginal microorganisms