Survey of Prophylactic use of Antibiotics among Indian Neurosurgeons
Correspondence Address: Source of Support: None, Conflict of Interest: None DOI: 10.4103/0028-3886.333485
Source of Support: None, Conflict of Interest: None
Keywords: Antibiotic prophylaxis, brain surgery, spine surgery, surgical site infections, survey
Use of prophylactic antibiotics for prevention of infection in elective neurosurgery has been a contentious issue but several published series have supported their use.,,,, The World Health Organization (WHO) provides recommendations on the administration of surgical antibiotic prophylaxis prior to surgical incision when indicated, depending on the type of operation and its timing and duration. WHO has also incorporated its use in the surgical safety checklist for all surgical cases.
Despite available guidelines there is a wide variation in the administration, use and duration of surgical antibiotic prophylaxis (SAP) in neurosurgery. To better understand the trends in the use of SAP across various practice models and institutions in India, we gathered information pertaining to their use in commonly performed clean, elective, non-trauma cranial and spinal procedures. To our knowledge, this is the first such survey conducted amongst Indian neurosurgeons.
A questionnaire [Supplementary file 1] was formulated on Survey Monkey™ (www.surverymonkey.com), which included 17 questions regarding the use of antibiotic prophylaxis in various neurosurgical procedures. The questionnaire was anonymous and included questions on if SAP was routinely used in their practice, the class and duration of antibiotics used for various brain and spine procedures and the employment of a regular audit on SSIs.
This questionnaire was first sent in April 2018, via e-mail to 2,175 neurosurgeons across India who had a registered email address with the Neurological society of India. Three reminders were sent at 3 monthly intervals, the final reminder being sent in April 2019. The survey was closed in July 2019. The responses were charted in an Excel database (Microsoft Inc, Seattle, USA) and analyzed.
Types of surgery
Surgical types were categorized as: cranial surgery, trans-sphenoidal surgery, spine surgery without instrumentation, spine surgery with instrumentation, and ventriculo-peritoneal (VP) shunt surgery.
Hospitals were categorized as teaching hospitals when they had a neurosurgical training program (M.Ch. or Diplomate of the National Board). Surgeons practice locations (hospitals) were categorized as following: government teaching, trust teaching, corporate teaching, corporate or trust non-teaching and other private practice. For comparison, government teaching and trust teaching hospitals were considered together and all other practice locations as the other group.
Significance in differences in proportions was calculated using Fisher's exact test or Chi-square test. A P value of < 0.05 was considered as significant.
Of the 2,175 e-mails sent, we received 103 (4.74%) responses after three reminders. Approximately 90% of the responses were obtained after the first mailing, 9% after the second mailing, and only 1% after the last mailing. Not all responders answered all questions and hence there were different denominators for the different questions.
Ninety-two responders mentioned the location of their practice. The regional distribution of the responders was as follows: south 55 (59.8%), north 12 (13%), west 12 (13%), east 6 (6%), central 6 (6%), and north-east 1 (1%).
Forty-three percent of the surgeons worked in a government or not-for-profit trust teaching hospital, 25.1% worked in a corporate for profit teaching hospital, 27.5% worked in a non-teaching corporate/private hospital, and the rest (3.9%) in a non-teaching government or not-for-profit trust hospital. The antibiotic policy was determined by the individual surgeon in 24.8% of the cases, by the surgical unit in in 32.7% and by the Institution's infection policy-making authority in 42.6%. So in most instances (>75%), it is either the unit or hospital policy that determines the SAP.
Annual number of surgeries
All the responders' departments performed substantial numbers of cranial and spinal surgeries. Fifty-one (50%) of the responders performed ≤ 500 surgeries in the last 1 year, 32 (31.4%) performed between 501 and 1,000 surgeries, while 6 (5.9%) performed 1,001 to 1,500 surgeries in the last 1 year. Thirteen (12.7%) responders belonged to institutes where > 1,500 surgeries were done in the last 1 year.
Surgical site cleaning solution
Out of 102 responders to the query on cleaning solution used, 46 (45.1%) surgeons preferred povidone iodine and 41 (40.2%) used a combination of povidone iodine and chlorhexidine. The remaining 15 (14.7%) surgeons used povidone, Sterillium (Hartmann AG, Germany), spirit, povidone scrub, tincture of iodine, alone or in combination.
Number of antibiotics used
An overwhelming number of neurosurgeons used a single antibiotic for cranial surgery (85%), spine surgery without instrumentation (82%) [Table 1], VP shunt surgery (72%), trans-sphenoidal surgery, (65%) and spine with instrumentation (64%) (Chi-square statistic 18.4496, P = 0.001). Around 30% of neurosurgeons preferred to use dual antibiotics in trans-sphenoidal, spinal instrumentation cases, and VP shunt surgery. Only 5–7% of responders preferred > 2 antibiotics and this preference was reserved for trans-sphenoidal and spinal instrumentation cases.
Family of antibiotics used
Considering all surgeries, cephalosporins (first to third generation) were the predominant antibiotic family that was used as SAP [Table 2]. Use of cephalosporins (of different generations), either alone or in combination with other antibiotics, ranged from 89.8% in spinal instrumentation surgeries to 97% in cranial surgeries. Of the cephalosporins, third-generation cephalosporins (cefotaxime, ceftriaxone, ceftazidime and cefixime) were the most commonly used antibiotics. Their use as monotherapy ranged from 33% for spinal instrumentation surgeries to 54.5% for cranial surgery. In combination with another antibiotic, third-generation cephalosporins use ranged from 13.1% in cranial surgeries to 27.8% in spinal instrumentation surgeries.
Specific antibiotics used [Supplementary file 1]
When monotherapy was used as SAP, ceftriaxone was the commonest antibiotic used (~50%), followed by cefuroxime and cefazoline, across the entire spectrum of cases.
Interestingly, three antibiotics were used as prophylaxis most often in patients undergoing trans-sphenoidal surgeries (6 responders) and spinal instrumentation surgeries (5 responders). Only one surgeon used three antibiotics for cranial cases and another for VP shunt surgery.
Four antibiotics were only used by one surgeon for trans-sphenoidal surgery.
Duration of antibiotic use
One dose or 1 day of SAP was used by the least number of responders (29%) for spinal instrumentation surgeries and the most responders for spinal surgery without instrumentation (66.7%) (Chi-square statistic 27.7672, P = .000014). For other surgeries, the number was within this range [Table 3].
Over 70% of surgeons use SAP for <3 days except for spinal instrumentation surgeries where slightly <65% used SAP for <3 days. SAP for >3 days was used by the most number of responders (36.1%) for spinal instrumentation surgeries followed by VP shunt surgeries (27.2% responders) and trans-sphenoidal surgeries (24.7% responders).
Only 2.3% of surgeons reported >7 days of prophylactic antibiotics use for spinal instrumentation cases.
Influence of practice setting
The proportion of surgeons using a single antibiotic for different surgical procedures was higher in the government/trust teaching hospital setting when compared to those working in corporate teaching/non-teaching hospitals. However, these differences were not statistically significant [Table 4].
A significantly higher proportion of surgeons working in corporate teaching/non-teaching hospitals used antibiotics for ≥1 day for cranial surgeries (P = 0.04), spinal surgeries without instrumentation (P = 0.006), and VP shunt surgery (P = 0.04). For trans-sphenoidal surgery also there was a similar trend but the difference did not reach statistical significance (P = 0.06).
There was no difference in the antibiotic policy between surgeons who practiced in centers where ≤ 500 cases were done per year and those who practiced in centers where > 500 cases were done per year.
Only 61 (59.8%) of the 102 responders reported that an infection audit is performed in their institute. Of these 61 responders, 57 reported a SSI rate in the range of 0.06–6% (mean, 2.5% in the last two years.
Infection related mortality
Out of 101 surgeons, only 16 (15.8%) reported deaths due to SSI in the last one year. Of them, 12 (11.8%) mentioned <5 deaths at their institute and one (0.9%) reported 6–10 deaths. Three surgeons (2.9%) reported deaths but could not provide a specific number.
Surgical site skin preparation
Based on several Randomized Control Trials (RCTs) the WHO recommends alcohol-based antiseptic solutions that are based on chlorhexidine gluconate for surgical site skin preparation. A significant reduction of the SSI risk was shown with the use of alcohol-based chlorhexidine gluconate compared with either aqueous povidone-iodine or povidone-iodine in alcohol-based solutions. In our survery, povidone iodine as a preoperative cleaning solution was used by 45% of surgeons, while a chlorhexidine based solution was used only by 9.8% and a combination of povidone and chlorhexidine based solution by 40.2%.
Recommended prophylactic antibiotics
The majority of studies on SAP report a protocol of a single dose of antimicrobials. Use of single-dose antimicrobial prophylaxis given within 60 mi before the surgical incision in patients undergoing neurosurgery is generally recommended. However, when deciding on the drug for SAP for an individual patient, the patient's comorbidities, allergies, length, and complexity of the procedure and issues of antibiotic resistance should also be considered., Our survey results revealed that <50% of surgeons used SAP for <1 day for cranial surgeries and only about 25% gave a single dose of antibiotics.
Currently, a single dose of cefazolin (not followed by further antibiotic administration) is recommended by the AAHP/IDSA/SIS/SHEA (American Society of Health System Pharmacists, the Infection Disease Society of America, Surgical Infection Society, the Society for Healthcare Epidemiology of America) for patients undergoing clean neurosurgical procedures. However in our survey, the use of a first-generation cephalosporin (either alone or in combination) was reported by only 5.2–11.1% of surgeons for different neurosurgical procedures.
Liu et al., studied the role of third-generation cephalosporins which included five randomized controlled trials (RCTs) enrolling a total of 2,209 patients. The study failed to show superiority of third-generation antibiotic prophylaxis over conventional regimens (broad spectrum penicillins, first/second-generation cephalosproins, aminoglycosides, and glycopeptides regarding both incisional and organ related SSI in neurosurgery. Interestingly, our survey showed that >60% of the responders used a third-generation cephalosporin, either alone or in combination, for different neurosurgical procedures.
The use of SAP should be weighed against the costs and potential side effects, including allergic reactions, Clostridium difficile enterocolitis, and spread of antimicrobial resistance. Hence, use of the lowest generation of antibiotics and for the shortest duration of time would be the ideal protocol for SAP.
Surveys for SAP in neurosurgery
Response to surveys in neurosurgery have generally been less than satisfactory.,, Web-based surveys in particular have a low response rate. Our response rate was 4.75%.
Matsuda et al. conducted a survey on SAP in Japan and concluded that several practices related to SAP were not in keeping with the WHO guidelines, especially with regard to the duration of antibiotic use. Their survey showed that 80% of Japanese neurosurgeons administered antibiotics beyond the recommended 24 h.
In another survey conducted by Little and White in the United States on the use of SAP in trans-sphenoidal surgeries for pituitary lesions, 76% used only one class of antibiotics, but 22% used two antibiotics and 2% used three antibiotics. We noted similar trends in our survey. In our survey, 35% of surgeons used >1 antibiotic and only 40.4% of surgeons used antibiotics for ≤1 day for trans-sphenoidal surgeries. Fang et al. surveyed the use of SAP for anterior skullbase surgery. Most surgeons (95%) gave SAP. Most used a first or second-generation cephalosporin (55.5%) while a third to fifth-generation cephalosporin was also used by a large number of surgeons (43.4%).
A recent international consensus document on spine surgery recommended that the optimal prophylactic antibiotic for uncomplicated spine surgery is a first-generation or second-generation cephalosporin given intravenously within 60 min of the initial incision, a single preoperative dose being sufficient. We noted that while 81.8% of surgeons administered only one antibiotic for spine surgeries without instrumentation, this percentage dropped to 64% for instrumented spine surgeries. Also the use of SAP beyond 1 day was reported by 71% of surgeons for instrumented spine surgeries as opposed to only 33.3% for non-instrumented spine surgeries.
SAP in different practice settings
Little and White found no significant relationship between antibiotic choice, duration, or incidence of meningitis and practice setting or duration of practice when they surveyed for the use of SAP for trans-sphenoidal surgery.
A study on SAP from Iran evaluated SAP policies in private and public hospital settings across various specialties including neurosurgery. They found that approximately 90% of patients received inappropriate surgical prophylaxis in private hospitals in the form of prolonged duration of antibiotics administration beyond that recommended by guidelines. Only 20% of patients in private hospitals received a single-dose antibiotic as SAP.
Indian publications on surgical antibiotic prophylaxis
Moorthy et al. from Vellore, used a conservative SAP regime of using either a 1-day course of intravenous chloramphenicol or a single dose of ceftriaxone for cranial cases that resulted in bacterial meningitis in 0.8% of their 3401 craniotomies restrospective analyzed. When they added a staphylococal decolonization regime to their protocol they found a reduction in both bacterial and aseptic meningitis rates, the latter being statistically significant. Sharma et al. from Delhi concluded that using a risk-stratified protocol of perioperative antibiotic prophylaxis helps to significantly decrease not only postoperative bacterial meningitis rates, but also infections at other systemic sites such as the respiratory and urinary tracts. Srinivas et al., from Bangalore reported an incidence of bacterial meningitis rate of 2.2%in 18,092 patients. Cefotaxime alone or in combination with amikacin and metronidazole were used for different categories of patients, the duration ranging from 24 h to 72 h.
Almost all our survey respondents had different SAP protocols for different surgeries. In other words, neurosurgeons in India use some form of risk stratification when deciding on the SAP for different surgeries.
The obvious limitation of our study is the poor response rate to the survey, which limits our ability to generalize the findings to the practice of neurosurgery in the country as a whole. Due to the anonymous nature of the survey, it was difficult to determine if more than one person from the same department replied which could result in a potential skewing of results. Questions on preoperative preparation of the patient, which may impact on SSI, such as hair removal, hair wash prior to surgery, staphylococcal decolonization, and nutritional optimization were not discussed in this study. The timing of antibiotic administration in relation to the incision was also not queried. Finally, we did not seek justification of the prophylactic antibiotic policy and are therefore unable to understand the policies for different surgeries in different centers. However, we wanted to keep the survey as brief as possible with a focus on the class and duration of antibiotics used in different types of neurosurgical cases.
Almost all neurosurgeons in India administer SAP. A significant proportion of surgeons prescribe SAP for more than 1 day. Surgeons perceive patients undergoing trans-sphenoidal surgeries, instrumented spine surgeries, and VP shunt surgeries to be most at risk for SSI. Hence, they tend to prescribe multiple antibiotics for longer duration to these patients. Surgeons practicing in corporate teaching and non-teaching hospitals are more likely to administer SAP for more than 1 day as compared to their peers practicing in government/trust teaching hospitals. The reasons for this are unclear.
We thank all the neurosurgeons who participated in the survey. We are grateful to Dr. Ranjith K Moorthy for his help with the questionnaire.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
Antibiotic prophylaxis in elective (non-trauma) neurosurgery (this survey applies to practices at least for the last 2 year)
1. Do you use antibiotic prophylaxis for elective surgery (cranial and spinal)?
If no, proceed to Question 9
2. If yes, is the selection of antibiotics based on a written protocol?
3. What dictates the antibiotic policy?
Decided by the institution's infection policy making authority.
3. Please specify the antibiotics used (generic name only) for the following cases:
Cranial (open/endoscopic/DBS) surgery
Spinal surgery without instrumentation
Spinal Surgery with instrumentation
4. What is the duration of prophylactic antibiotic therapy for cranial (open/endoscopic/DBS) surgery?
Single Dose only
More than 1 dose but less than a day
5. What is the duration of prophylactic antibiotic therapy for trans-sphenoidal surgery?
Single Dose only
More than 1 dose but less than a day
6. What is the duration of prophylactic antibiotic therapy for spinal surgery without instrumentation?
Single Dose only
More than 1 dose but less than a day
7. What is the duration of prophylactic antibiotic therapy for spinal surgery with instrumentation?
Single Dose only
More than 1 dose but less than a day
8. What is the duration of prophylactic antibiotic therapy VP shunts?
More than 1 dose but less than a day
9. Do you or your unit have an infection audit on a monthly or annual basis?
10. If yes, please mention the yearly surgical site infection (SSI) rate for the last 2 years. Do not include exclusive urinary, respiratory or other site infections. If patient has SSI along with other site infections, please include.
11. If no, then please provide an estimate of SSI for the last 2 years:
12. What solution do you use for pre-operative surgical site cleaning:
Povidone Iodine based solution
Chlorhexidine based solution
Combination of povidone and chlorhexidine based solution
13. In the last 1 year, has any patient died due to a Surgical Site Infection (SSI)?
14. If yes, how many patients have died?
15. Where do you primarily work?
Teaching hospital (government or trust not for profit)
Teaching hospital (corporate for profit)
Non-teaching government or trust not for profit
Non-teaching corporate/private hospital
16. How many elective cranial/spinal cases did you/your unit operate in the last 1 year.
17. Any other information with respect to SSI that you would like to provide?
[Table 1], [Table 2], [Table 3], [Table 4]