One of the problems in controlled hypotension (CH) during surgery is the difficulty in determining patient characteristics and the advantages and disadvantages of the drugs used.
Controlled hypotension is defined as a reduction in systolic blood pressure to 80-90 mmHg and a reduction in mean arterial pressure (MAP) to 50-65 mmHg or a 30% reduction over baseline MAP. Controlled hypotension is often associated with the pharmacology of the drugs used. One of the drugs often used as a comparator for CH therapy is remifentanil and dexmedetomidine.
A meta-analysis study was conducted to compare the effectiveness and safety of remifentanil vs dexmedetomidine in controlling hypotension in patients undergoing general anesthesia. The method was to collect randomized controlled trial (RCT) studies that met the inclusion criteria from PubMed, EMBASE, Web of Science, CNKI, SinoMed, Wanfang, and VIP databases until August 2021. The primary parameters assessed were hemodynamic profile, operative visual field score, and blood loss. The secondary parameters were extubation time, sedation and pain scores in the post-anesthesia care unit (PACU), and perioperative side effects.
The results of 9 studies with 272 patients who received dexmedetomidine and 271 patients who received remifentanil showed that there was no difference between the administration of dexmedetomidine and remifentanil on the operative visual field score, blood loss, minimum MAP value, heart rate, sedation score in the PACU, and the incidence of bradycardia. Compared with remifentanil, dexmedetomidine as CH had lower VAS score in PACU (MD -1.01 [-1.25, -0.77], p<0.00001), lower incidence of chills (OR 0.22 [0.08, 0.60], p=0.003, nausea and vomiting (OR 0.34 [0.13, 0.89], p=0.03). Extubation time was shorter with remifentanil (MD 3.34 [0.75, 5.93], p=0.01).
Conclusion:
The meta-analysis showed that both dexmedetomidine and remifentanil are effective for controlled hypotension and surgery. Dexmedetomidine has a better effect on post-operative pain and can reduce the incidence of chills, nausea, and vomiting. Meanwhile, remifentanil provides a rapid anesthetic effect, resulting in a shorter extubation time.
Image: Illustration (Source: Envato element)
Reference:
Xu N, Chen L, Liu L, Rong W. Dexmedetomidine versus remifentanil for controlled hypotension under general anesthesia: A systematic review and meta-analysis. PloS ONE. 2023;18(1):e0278846.
