Spinal anaesthesia at low and moderately high altitudes: A comparison of anaesthetic parameters and hemodynamic changes
Mehmet Aksoy1, Ilker Ince1, Ali Ahıskalıoglu1, Omer Karaca2, Fikret Bayar3, Ali Fuat Erdem3
1Department of Anaesthesiology and Reanimation, Faculty of Medicine, Ataturk University, Erzurum, Turkey
2Department of Anaesthesiology and Reanimation, Ordu State Hospital, Ordu, Turkey
3Department of Anaesthesiology and Reanimation, Faculty of Medicine, Sakarya University, Sakarya, Turkey
INTRODUCTION: It has been reported that the amount of cerebrospinal fluid (CSF) increases and acid-base balance of CSF changes because of hypoxemia at high altitude. AIM: We aimed to compare the anaesthetic characteristics and hemodynamic variations following a single-shot spinal anaesthesia in patients living at different altitudes. MATERIALS-METHODS: Consecutive patients living at moderately high altitude (Erzurum, 1890 metres above the sea level) and the sea level (Sakarya, 31 metres above the sea level) scheduled for elective lower extremity surgery with spinal anaesthesia were enrolled in this study (n=70, for each group). Spinal anaesthesia was provided with hyperbaric bupivacaine 0.5%, 9 mg (1.8 mL). Anaesthetic characteristics and hemodynamic parameters of patients were recorded. RESULTS: Duration of the block procedure (minutes) was significantly shorter at the sea level (14.34 ± 0.88) than at moderate altitude (20.38 ± 1.46) (P < 0.001). Motor block duration (minutes) was higher at the sea level compared to the moderate altitude (310.2 ± 104.2, 200.4 ± 103.2; respectively; P < 0.05). Also, the sensory block time (minutes) was higher at the sea level compared to moderate altitude (200.2 ± 50. minutes vs. 155.2 ± 60.7 minutes; respectively; P < 0.05) (Table 1). Moderate altitude group had significantly higher MABP values at baseline, during surgery and at postoperative 1st and 2nd hours than in the sea level group (P < 0.05) (Fig. 1). Moderately high altitude group had lower heart rate values at baseline, during surgery and postoperative 1st and 2nd hours compared with the sea level group (P < 0.05) (Fig. 2). CONCLUSION: Hemodynamic variations and more anaesthetic requirements following the spinal anaesthesia may be observed at moderately high altitudes compared to the sea level. These differences may be associated with a physiological adaptation to chronic hypoxia in individuals living at moderately high altitude.
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