Role of Perioperative Antibiotics in Endoscopic Skull Base Surgery

Design

Retrospective, observational, database study

N= 90

Objective

Study Groups

Patients with intraoperative CSF leak (n=58)

Patients without intraoperative CSF leak (n=32)

Inclusion Criteria

Patients who had undergone endonasal skull base or pituitary surgery during the study period; were deemed to have adequate records

Exclusion Criteria

Incomplete data

Methods

This was a case series of 24-48 hours of single-agent perioperative antibiotics in patients who underwent endoscopic skull base surgery at a single tertiary-care center. Patient data was prospectively collected in a database that contained the office, hospital, and operative records of all patients that had undergone endoscopic skull base and pituitary surgery by the senior authors of this paper.

All of the patients underwent an endoscopic procedure and routinely received a single-agent IV antibiotic for 24 to 48 hours. Patients who had no known history of allergy received cefazolin 1 gram Q8H, while patients who had a known history of penicillin allergy received either vancomycin 1g Q12H or clindamycin 600mg IV Q8H. The choice between these two antibiotics was at the discretion of the surgeon.

The first dose of antibiotic was given at the time of induction with general anesthesia prior to the commencement of the procedure. Antibiotics were discontinued folowing nasal pack removal on postoperative day one or two. Once the patients were discharged, they underwent routine endoscopic examination and debridement of the sinonasal cavity.

Patients were then placed on gentamicin nasal spray (80 grams of gentamicin in 1 liter of normal saline) to start 2 weeks after surgery until the wound cavity was considered well healed, which was usually 2 to 3 months post-surgery. Those patients who were noted to have a clinical history and endoscopic findings consistent with sinusitis at follow-up received outpatient oral antibiotic therapy empirically in order to prevent more serious infections. 

Duration

Following discharge, patients were seen for an additional 2 to 3 months in order to ensure that their wound cavity had healed well. 

Outcome Measures

The main outcomes of this study were the occurrence of infectious complications and the need for additional antibiotics.

Baseline Characteristics

Results

Intraoperative CSF leak

(n=58)

No intraoperative CSF leak

(n=32)

p-value

Histologic diagnosis

Secreting pituitary adenoma

Nonsecreting pituitary adenoma

Meningioma

Craniopharyngioma

Encephalocele

Other

12 (21%)

17 (29%)

7 (12%)

7 (12%)

8 (14%)

7 (12%)

19 (59%)

8 (25%)

0

1 (3%)

0

4 (12%)

0.01

NS

NS

NS

NS

NS

Cefazolin was used in 79 (88%) patients, vancomycin was used in 8 (8%) patients, and clindamycin was used in 3 (3%) patients. There no cases of meningitis or intracranial infections found in either group. Moreover, no antibiotic-related complications occured during the study. 

The differences between the two groups, in terms of their need for antibiotics during hospitalization or at follow-up, did not reach statistical significance. Additional antibiotics that were given during hospitalization were used in patients with a CSF leak to treat two (3%) patients with urinary tract infections, one (2%) patient with sinusitis, two (3%) patients for lumbar drain prophylaxis, one (2%) patient for postoperative fever, and one (2%) patient with aspiration pneumonia. Only one (3%) patient without CSF leak was given additional antibiotics in order to treat a case of sinusitis. 

Thirteen (22%) patients with a CSF leak and six (19%) patients without a CSF leak were given antibiotics during the first three months of follow-up in order to treat sinusitis or a nasal cavity infection. All of these infections were limited to the intranasal space and were successfully treated on an outpatient basis. 

Adverse Events

None reported

Study Author Conclusions

A single-agent antibiotic covering Gram-positive organisms for 24 to 48 hours may be adequate in anterior endoscopic skull base surgery to prevent serious CNS infectious complications.

InpharmD Researcher Critique

While researchers may not have found a significant difference in postoperative infectious outcomes between patients with and without intraoperative CSF leak, this could have been due to the fact they had a sample size of only 90 people. Furthermore, there was some heterogeneity between patients, tumor, and surgical variables that may have precluded identification of a specific indication for broad-spectrum antibiotics. 

Antibiotic prophylaxis in endoscopic endonasal pituitary and skull base surgery

Design

Retrospective, cohort

N= 2,032

Objective

To assess the efficacy of our intraoperative antibiotic prophylaxis, analyzing the risk factors of postoperative meningitis

Inclusion Criteria

Patients who underwent endoscopic endonasal procedures at a single center in Italy; patients followed up for at least 30 days

Exclusion Criteria

Methods

Each endoscopic endonasal procedure performed since 1998 in patients with no preoperative infections and a follow-up longer than 30 days were included in this study. The antibiotic protocol consisted of single antibiotic administration of ampicillin/sulbactam 3 g or cefazolin 2 g on induction. No postoperative antibiotics were administrated after 2005. All cases of CSF leak, meningitis, and systemic infection were recorded.

Duration

1998 to 2016

Baseline Characteristics

All patients (N= 2,032)

Age, years

Female

Results

Meningitis incidence

p-value

Intraoperative CSF Leak

Yes

No

12/666 (1.8%)

2/1366 (0.2%)

Postoperative CSF Leak 

Yes

No

7/69 (10.1%) 

7/1963 (0.4%)

CSF Leak

Intraoperative only

Postoperative only

Intraoperative and Postoperative

6/449 (1.3%)

1/14 (7.1%)

6/45 (13.3%) 

Intraoperative CSF leak occurred in 32.8% of the cases and postoperative CSF leak in 3.4%. The overall rate of meningitis was 0.69%.

Meningitis was statistically associated with intra- and post-operative CSF leak (p< 0.001). Other risk factors were the intradural extension of the tumors and their malignant histology. Extended approaches producing wide osteo-dural defects were also correlated with a higher risk of meningitis (p< 0.001)

Adverse Events

N/A

Study Author Conclusions

All surgical maneuvers to prevent, detect, and quickly repair intra- and postoperative CSF leak are crucial to avoid postoperative meningitis. The proposed prophylaxis protocol is comparable in safety to those recommended in literature as assessed by the low rate of meningitis.

InpharmD Researcher Critique

This study was not randomized and was retrospective. The retrospective design relies on proper documentation of healthcare providers, which some may have omitted certain information. Although the rate of meningitis is low and in line with others reported in the literature, the change of antibiotic prophylaxis protocol in 2005 might be considered a limitation of this study.