Role of Supplemental Oxygen in Perioperative Period for Reducing Surgical Site Infection: A Comparative Hospital Based Study

Azher Mushtaq, Department of Surgery, Government Medical College Srinagar, India, Email: azharmushtaq82@gmail.com

Received: 23-Nov-2020 Published: 14-Dec-2020

Introduction

Traditionally, Sepsis has been regarded as an insult to the surgeon and surgeons are always in search of methods of reducing and minimising the occurrence of post-surgical infection and sepsis. Still Infection forms a major complication of surgical procedures, and among surgical patients, surgical site infection (SSI) is the most common nosocomial infection reported [1]. SSIs prolong hospital stay, increase the cost of care, and are associated with increased mortality [1-3]. There are various factors, which predispose to SSI including host factors and environmental factors. The host-derived factors which contribute importantly to the risk of SSI, include, age, obesity, malnutrition, diabetes mellitus, hypocholesterolemia, immunocompromised states, hypoalbumenemia and several other factors not accounted for by National Nosocomial Infections Surveillance (NNIS) System [4-6]. Intraoperative hypothermia is also associated with an increased incidence of SSIs following many operations [7]. Determining the avoidable factors that affect SSI can therefore allow to improve the outcome after surgery [8]. The risk of infection at a surgical site is related to the number of bacteria that reach the surgical wound and the body’s ability to kill these bacteria within the first few hours of the woundhealing process [9]. Destruction by oxidation or oxidative killing is one of the most important defences against surgical pathogens and depends on the partial pressure of oxygen in contaminated tissues [10]. Although controversial whether perioperative oxygen administration is beneficial for the prevention of infection, Oxygen partial pressures and wound tissue oxygen tensions have been shown to correlate with oxidative killing and have been reported to predict SSI rates [11,12]. We therefore performed a study to evaluate the role of perioperative orthobaric supplemental oxygen therapy (high FIO2) in preventing the occurrence of surgical Site Infections (SSIs).

Materials and Methods

The study was a comparative study conducted in the Postgraduate Department of General Surgery, Government Medical College Srinagar at SMHS Hospital from August 2016 to March 2018. A total of 100 patients were included in the study. Patients were divided into two groups alternately with 50 patients in each group. Both the groups were matched in age, sex and type of surgery. One group (Study group) was subjected to peri-operative oxygen supplementation (high FIO2; 60% oxygen) and the other group (Control group) was subjected to (30% oxygen) perioperatively. The patients in the study group received 60% fraction of inspired oxygen intra-operatively and 2 hours post operatively, the other group received room air post operatively. During intra-operative period, the oxygen was delivered by Boyle’s apparatus 60% under general anaesthesia. Postoperatively oxygen was delivered through Poly mask at a rate of 6 lits/min in study group and 3 lits/min in other group. Operative wounds were examined on second, fifth and eighth postoperative days for the signs of SSI. Follow up was done for 30 days. Patients of both groups were observed for the occurrence of wound infection. The wound infection was diagnosed clinically by the presence of clinical signs including local induration, erythema, tenderness, warmth, wound discharge, crepitus etc. described by the Centers for Disease Control Recommendations to Prevent Surgical Site Infections [13].

Inclusion Criteria

All operated patients with clean (Class I) and clean contaminated (Class II) wounds between 15-60 years of age.

Exclusion Criteria

• Patients with contaminated (Class III) and dirtyinfected wounds (Class IV)

• American Society of Anesthesiology class 3 and above and moribund patient populations

• Purely laparoscopic (non–hand-assisted) procedures

• Minor outpatient (day-case) surgery cases

• Neonatal cases

Results and Observations

In our study, in a total of 100 patients, 50 belonged to control group and 50 to study group. The male female ratio was 26:24 in control group and 28:22 in study group respectively as shown in Figure 1 (p-value being)

Figure 1. Graph showing Gender distribution of patients in our study.

The mean age of patients in our study was 39.52 ± 11.55 years, while as the mean age in study group was 39.8 ± 11.18 years and in control group was 39.27 ± 12.02 years as shown in the Figure 2 (P-value being)

Figure 2. Graph showing Gender Difference of patients in between Age group and Mean age group.

In our study, the Mean BMI of patients in the Study Group was 21.7 ± 9.2 and the mean BMI of the Control Group was 23.7 ± 8.6. The difference was however statistically insignificant. P-Value being 0.78 shown in the Figure 3 (P-value being)

Figure 3. Graph showing Gender Difference of patients in between Body mass Index and Mean BMI.

The Various surgical procedures done in class-1 category patients are cholecystectomy, hernia repair, mastectomy, parathyroidectomy, thyroidectomy,and lipoma excision as shown in Table 1. Out of these proceduresCholecystectomy (open) was the major procedure.

The various class II surgical procedures (clean contaminated) done in the two groups in our study were shown Table 2.

In our study we observed that the infection rate in the study group who received 60% fraction of inspired oxygen perioperatively was 20%, i.e 10 out of 50 patients developed surgical site infections while as in control group who received 30% fractions of inspired oxygen perioperatively, 36% of patients i.e 18 out of 50 (control group) patients developed surgical site infections Table 3. The difference between the two groups was statistically significant with p value of 0.043676.

Discussion

Surgical site infection (SSI) is a major complication of surgery, associated withprolonged hospitalization, increased costs and increased morbidity and mortality. In recent years, randomized trials have identified a number of preventive measures that can substantially reduce the risk of SSI. These include appropriate perioperative antibiotic prophylaxis, maintenance of perioperative normothermia and control of hyperglycaemia. The effect of perioperative oxygen supplementation continues to be under debate with proponents and opponents firmly divided over the issue. Number of studies have been conducted to assess the benefits of such perioperative oxygen therapy in preventing SSIs which have however yielded mixed results [11,14]. While some have shown a considerable reduction in the incidence of SSI, others have found an increased risk of SSI in patients receiving supplemental oxygen [10,14]. While a higher concentration of oxygen supplementations (80%) has been found to reduce the SSIs by half, inspiring a higher concentration of oxygen is not devoid of complications [12,15]. It can induce lung injury and atelectasis in patients at risk [16,17]. Therefore, this study was performed to evaluate the role of perioperative supplemental oxygen therapy (high FIO2) in preventing the occurrence of surgical Site Infections (SSIs). In our study, we divided patients in two groups, 50 patients in control group and 50 in study group. The male female ratio was 26:24 in control group and 28:22 in study group respectively. In our study, the mean age of total study population (100) was 39.52 ± 11.55 years. The mean age in study group (50) was 39.8 ± 11.18 years and 39.27 ± 12.02 years in the control group respectively. Mean BMI of the Study group and control group in our study was 21.7 ± 9.2 and 23.7 ± 8.6 respectively. Mean BMI between the two groups was compared and there was no significant statistical differences observed in the BMI between the two groups (p value 0.78) which supports the findings of Pascal Thibon, et al, 2012 as they found in their study, the body mass index (27.1) of study group versus control group (26.5) was statically non-significant [18]. In our study, we observed that 10 out of 50 patients in study group who received 60% Fio2 perioperatively developed surgical site infection while as in control group that received Fio2 30%; 18 out of 50 patients developed wound infection. On comparing these results, we observed a statistically significant difference in the infection rates between the two groups (P value=0.043676). this is consistane with the findings of Tejaswini Vallabha, et al 2016; Belda FJ et al; Ahmad Al Niamiet al 2008 and Motaz Qadan et al 2009 who also have reported that oxygen supplementation in perioperative period resulted in a significant reduction in surgical site infection rates in clean and clean contaminated surgeries [19-22].

Conclusion

From this study, we concluded that the use of hyperoxygenation throughout the surgical interventions in different elective surgeries has a major effect on the frequency of SSI without an increase in the frequency of adverse effects. So, from the results of this study, we recommend the use of 60% supplemental perioperative oxygen in patients undergoing general surgical procedures as a cheap and safe method of reducing the risk of surgical site infections.

Conflict of Interest

The authors declare no conflict of interest.

References

1. Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvis WR. Guideline for prevention of surgical site infection, 1999. Centers for Disease Control and Prevention (CDC) hospital infection control practices advisory committee. Am J Infect Control 1999;27(1):97-132.
2. Nichols RL. Preventing surgical site infections: a surgeon's perspective. Emerg Infect Dis 2001;7(2):220-24.
3. McGarry SA, Engemann JJ, Schmader K, Sexton DJ, Kaye KS. Surgicalsite infection due to Staphylococcus aureus among elderly patients: mortality, duration of hospitalization, and cost. Infect Control and Hosp Epidemiol 2004;25(6):461-67.
4. Raymond DP, Pelletier S, Crabtree TD, Schulman AM, Pruett AM, Sawyer AM. Surgical infection and the aging population. Am Surg 2001;67(9):827-32.
5. Pomposelli JJ, Baxter JK, Babineau TJ, Pomfret EA, Driscoll  DF, Forse DF, et al. Early postoperative glucose control predicts Nosocomial infection rate in diabetic patients. J Parenter Enteral Nutr 1998;22(2):77-81.
6. Delgado-Rodriguez M, Medina-Cuadros M, Martinez-Gallego G, Sillero-Arenas M. Total cholesterol, HDL-cholesterol, and risk of Nosocomial infection: A prospective study in surgical patients. Infect Control Hosp Epidemiol 1997;18(1):9-18.
7. Kurz A, Sessler DI, Lenhardt R. Perioperative normothermia to reduce the incidence of surgical-wound infection and shorten hospitalisation. Study of wound infection and Temperature Group. N Engl J Med 1996;334(19):1209-15.
8. Flores-Maldonado A, Medina-Escobedo CE, Rios-Rodriguez HM, Fernández-Domí­nguez R. Mild perioperative hypothermia and the risk of wound infection. Arch Med Res 2001;32(3):227-31.
9. Hopf HW, Hunt TK, West JM, Blomquist P, Goodson WH, Jensen JA, et al. Wound tissue oxygen tension predicts the risk of wound infection in surgical patients. Arch Surg 1997;132(9):997-1004.
10. Pryor KO, Fahey TJ, Lien CA, Goldstein PA. Surgical site infection and the routine use of perioperative hyperoxia in a general surgical population: a randomized controlled trial. JAMA 2004;291(1):79-87.
11. Belda FJ, Aguilera L, Asuncion JGL, Alberti J, Vicente R, Ferrándiz L, et al. Supplemental perioperative oxygen and the risk of surgical wound infection: a randomized controlled trial. JAMA 2005;294(16):2035-42.
12. Al Naimai A, Safdar N. Supplemental perioperative oxygen for reducing surgical site infection: A meta analysis. J Eval Clin Pract 2009;15(2):360-65.
13. Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvis WR. Guideline for Prevention of Surgical Site Infection, 1999. Centers for Disease Control and Prevention (CDC) Hospital Infection Control Practices Advisory Committee. Am J Infect Control 1998;27(2):97.
14. Greif R, Akca O, Horn EP, Kurz A, Sessler DI. Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection. Outcomes Research Group. N Eng J Med 2000;342(3):161-7.
15. Belda FJ, Aguilera L, Jose Garcia DLA, Alberti J, Vincente R, Ferrandiz L, et al. Supplemental perioperative oxygen and risk of surgical wound infection. JAMA 2006;294(16):2035-48.
16. Meyhoff CS, Wetterslev J, Jorgansen LN, Henneberg SW, Hogdall C, Lundvall L, et al. Effect of high perioperative oxygen on surgical site infection and pulmonary complications after abdominal surgery. JAMA 2009;302(14):1543-50.
17. Gottrup F. Physiology and measurement of tissue perfusion. Ann ChirGynecol 1994;83(3):183-9.
18. Thibon P, Borgey F, Boutreux SE, Hanouz JL, Coutour XL, Parienti JJ. Effect of Perioperative Oxygen Supplementation on 30-day Surgical Site Infection Rate in Abdominal, Gynecologic, and Breast Surgery. The American Society of Anesthesiologists, Inc. Lippincott Williams and Wilkins. Anesthesiology 2012;117(3):504-11.
19. Vallabha T, Karjo U, Kalyanappago V, Sindgikar V,  Nidoni R,  Biradar H, et al.  Rational Hyperoxia in the Perioperative Period: A Safe and Effective Tool in the Reduction of SSI. Indian J Surg 2001;78(1):27-31.
20. Belda FJ1, Aguilera L, García de la Asunción J, Alberti J, Vicente R, Ferrándiz L, et al. Supplemental perioperative oxygen and the risk of surgical wound infection: A randomized controlled trial. Erratum in JAMA 2007;294(23):29-73.
21. Al-Niaimi A, Safdar N. Supplemental perioperative oxygen for reducing surgical site infection: A meta-analysis. Journal of Evaluation in Clinical Practice 2009;15(2):360-5.
22. Qadan M,Akça O,Mahid SS,Hornung CA,Polk Jr HC. Perioperative Supplemental Oxygen Therapy and Surgical Site Infection. A Meta-analysis of Randomized Controlled Trials. Arch Surg 2009;144(4):359-66.