Endocrine Abstracts

Objectives

Impact of inhalation anaesthesia (IA) during thyroidectomy in the thyrotoxicosis syndrome (TTS) patients on the fluctuation the oxygen delivery (DO2).

Materials

90 TTS patients undergoing thyroidectomy. Depending on the type of anaesthesia, patients were divided into the «balanced analgesia-sevoflurane» group (BA-S) – 44 patients (where bilateral superficial cervical plexus blockade (BSCPB) was added to IA and was used IA in minimal flow scheme with FGF = 400 ml/min) and «control-sevoflurane» group(C-S) – 46 patients (monoanaetsthesia with FGF = 1000 ml/min). The anaesthetic depth control was performed by monitoring the bispectral index. The perioperative period was divided into the following stages: Stage 1 – primary examination by the anaesthesiologist; Stage 2 – the patient arrived at the operating room and connected to the monitoring; Stage 3 – immediately after anaesthesia induction and trachea intubation; Stage 4 – surgery start; Stage 5 – thyroid removal; Stage 6 – after wound suturing (end of surgery); Stage 7 – 24 hours after surgery. At all stages were assessed the hemodynamic parameters with measuring cardiac output (CO) by the estimated continuous cardiac output (esCCO) monitoring and oxygen delivery (DO2).

Results

The results indicate that IA with sevoflurane has an effect on hemodynamic parameters. The highest depression of DO2 has been noted at the stage 3 – after the IA induction and its initiation. Decreasing DO2 values was noted in both groups vs initial stages nr.1-2 (see Table.). It was found that in the next stages 4–6, the highest DO2 values were significantly noted in BA-S vs C-S, where use less aggressive scheme of IA due to better nociceptive control with BSCPB. The use of FGF = 2000 ml/min for IA induction and 400 ml/min for basic IA in BA-S reduces DO2 to a lesser extent compared to FGF = 4000 ml/min and 1000 ml/min in C-S respectively.

Conclusions

The study highlights the negative impact of both scheme general IA with sevoflurane on oxygen delivery in TTS patients, however use BSCPB affords reduced negative impact on oxygen delivery due to less doses IA.