About a two years ago an ENT surgeon I have never worked with requested that I use a TIVA for her patient who was having an endoscopic sinus surgery. I thought this an odd request. I did an initial literature search and indeed found a few studies supporting this concept. However, there were other studies that were not able to replicate this finding. Also, it was noted that remifentanil was alway included in the studies where TIVA was found to improve the visibility in the surgical field. Therefore, I came away from this review not fully convinced that propofol infusions could make a clinically relevant difference in the ability of the surgeon to see during sinus surgery. Furthermore, I could think of no biologic plausibility for this effect.
Today, I was completing my mandatory MOCA questions in the app that is provided. One of the questions asked what is the best choice of anesthesia to improve the visibility of the sugical field during endoscopic sinus surgery. The correct answer was a TIVA with remifentanil. This prompted me to once again do a literature reveiw to update my knowledge in this regard.
The main support for the idea that TIVA is ‘better’ than inhalational comes from a meta-analysis of over 500 [1] patients having endoscopic sinus surgery. In this meta analysis, the TIVA group, had better surgical field visibility. However, the real headline from the meta-analysis was probably that when you dive in, it appears that the benefit of TIVA is lost if you trade in fentanyl for remifentanil [2]. There is an RCT that does not support the findings of the meta analysis however [3]. This group had three arms, Desflurane only, Desflurane + remi, propofol + remi and found difference in FESS. It is important to note in this RCT, the MAP was carefully held at between 65 - 70 mmHg. Of note, in the propofol group, significantly larger remifentanil dosages were used to accomplish the same anesthetic end target. If remifentanil is important in improving the surgical field, then this may indicate why propofol in other studies might seem to produce better results when compared to inhalalational anesthetics.
Importantly, in this same literature search, I was able to identify several studies showing a benefit of lidocaine in improving surgical field visibility. In a 2024 systematic review, lidocaine was found to improve the surgical field in FESS surgery. In a RCT in 2022 [4], 1.5 mg/kg of lidocaine was given up front followed by a 1.5 mg/kg/hr infusion. This resulted in significantly reduced blood loss and improved surgical field visibility.
Other studies have also shown that controlled hypotension with either propofol or esmolol can reduce intraoperative blood loss in endoscopic sinus surgery and leads one to believe that the real culprit for the results seen in the above studies is more likely related to reduced sympathetic tone and blood pressure in the group that saw improved results.
Guven et al. [5] were able to show that dexmedetomidine was slightly better than remifentanil in improving the surgical field during FESS. Another group [6] in a RCT were able to demonstrated that adding an infusion of dexmedetomidine to a background anesthetic of propofol/remifentanil reduced blood loss and improved the visibility of the surgical field. Finally, in 2024, Warner et al. published a meta analysis [7] of 31 RCT with 935 patients. They were able to show that dexmedetomidine resulted in better surgical field visibility and reduced blood loss compared to placebo and compared to propofol.
Unfortonuately, our surgical colleagues, or more specifically, the ENT surgeons who may now request TIVA with propofol to improve visualization during endoscopic surgery may not be so nuanced. Therefore, it is likely that we are going be mandated in some cases to either spend effort attempting to explain the nuances of the studies, or simply add some propofol to our FESS anesthetics. Our friendly surgical colleagues will unfortunately be unaware that the most optimal surgical field visibility is likely going to result from optimal control of sympathetic outflow during surgery (i.e. avoiding elevated BP and HR). Currently, the evidence seems to suggest that using agents that lower blood pressure by inhibiting surges in sympathetic output can improve the surgical conditions during endoscopic sinus surgery. Given this information, I would opt for a propofol infusion if I was wanting to prevent PONV, but not if it was only for the improvement of the surgical field. It seems reasonable to add boluses of lidocaine in a dose that approximates 1.5 mg/kg iv bolus up front followed by doses that accumulate to 1.5 mg/kg/hr for the duration of the case. Additionally, I would strongly consider adding dexemedotimine given the evidence cited above. Furthermore, it is easier to use than remifentanil, tends to provide smoother emergence and has been linked to reduced post op delirium in the elderly and is very good at reducing emergence delerium in the younger ones.
1. Boezaart AP, Tighe PJ, Laur JJ, Yegiaian C, Bevensee AM.
Anesthesia Type and Surgical Field Visibility During Endoscopic Sinus Surgery: A Systematic Review and Meta-analysis.
JAMA Otolaryngol Head Neck Surg. 2021;147(1):23–32.
2. Kolia NR, Man LX. Total intravenous anaesthesia versus inhaled anaesthesia for endoscopic sinus surgery: a meta-analysis of randomized controlled trials. Rhinology. 2019 Dec 1;57(6):402-410. doi: 10.4193/Rhin19.171. PMID: 31329812.
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