Comparison of effect of electroacupuncture and nefopam for prevention of postanesthetic shivering in patients undergoing urologic operation under spinal anesthesia

A Randomized Controlled Trial for Prevention of Postspinal Anesthesia Shivering in Gynecological Surgeries: Mirtazapine vs. Dexamethasone

Background

The frequency of shivering regarding regional anesthesia is 55%. Newer effective and tolerable options for postspinal anesthesia shivering (PSAS) prophylaxis are necessary to improve patients' quality of care. This research assessed the impact of preemptive mirtazapine versus preemptive dexamethasone to decrease frequency and severity of PSAS in gynecological procedures.

Methods

300 patients booked for gynecological procedures under spinal anesthesia (SA) were randomly apportioned into three groups (100 each) to get one preemptive dose of 30 mg mirtazapine tablet (M group), 8 mg dexamethasone diluted in 100 ml of saline infusion (D group) or placebo (C group) two hours before surgery. Incidence of clinically significant PSAS was the primary outcome. Core temperature, shivering score, hemodynamics changes, adverse events, and patient satisfaction score were documented as secondary outcomes.

Results

Compared with C group, mirtazapine and dexamethasone decreased incidence of clinically significant shivering (74% vs. 16% and 31%, respectively; P < 0.001). M and D groups had less hypotensive episodes during 5–25 min after intrathecal injection (P < 0.001). 90 min after SA, tympanic temperatures were lower than baseline values in the three groups (P < 0.001). Pruritus, nausea, and vomiting were more often in C group (P < 0.001), whereas sedation was more frequent in M group (P < 0.001). C group had the lowest satisfaction scores (P < 0.001).

Conclusion

Prophylactic administration of mirtazapine or dexamethasone attenuated shivering with minimal hazards in patients scheduled for gynecological surgeries under spinal anesthesia with priority to mirtazapine. The trial is registered with NCT03675555.

Postspinal anesthesia shivering in lower abdominal and lower limb surgeries: a randomized controlled comparison between paracetamol and dexamethasone

Background

Shivering is known to be a frequent complication in patients undergoing surgery under neuraxial anesthesia with incidence of 40–70%. Although many pharmacological agents have been used to treat or prevent postspinal anesthesia shivering (PSAS), the ideal treatment wasn’t found. This study evaluated the efficacy of paracetamol and dexamethasone to prevent PSAS in patients undergoing lower abdominal and lower limb surgeries.

Methods

Three hundred patients scheduled for surgeries under spinal anesthesia (SA) were allocated into three equal groups to receive a single preoperative dose of oral paracetamol 1 g (P group), dexamethasone 8 mg intravenous infusion (IVI) in 100 ml normal saline (D group) or placebo (C group), 2 h preoperatively, in a randomized, double-blind trial. The primary endpoint was the incidence of clinically significant PSAS. Secondary endpoints included shivering score, the change in hemodynamics, adverse events (e.g., nausea, vomiting and pruritis) and patients` satisfaction.

Results

Clinically significant PSAS was recorded as (15%) in P group, (40%) in D group and (77%) in C group (P < 0.001). The mean blood pressure values obtained over a 5-25 min observation period were significantly higher in the D group (P < 0.001). Core temperature 90 min after SA was significantly lower in the 3 groups compared to prespinal values (P < 0.001). Nausea, vomiting and pruritis were significantly higher in the C group (P < 0.001). P and D groups were superior to C group regarding the patients’ satisfaction score (P < 0.001).

Conclusion

Paracetamol and dexamethasone were effective in prevention of PSAS in patients undergoing lower abdominal and lower limb surgeries compared to placebo controls.

Trial registration

ClinicalTrials.gov Identifier: NCT03679065 / Registered 20 September 2018 - Retrospectively registered, http://www.ClinicalTrial.gov.