Abstract：
The cold pressor test (CPT) involves cold water immersion of either the upper or lower limb(s) and elicits autonomic and hemodynamic increases via stimulation of pain and cutaneous thermoreceptors. It is unclear whether the choice of limb(s) in CPT studies differentially affects systemic and cerebral hemodynamic responses. Herein, we assessed systemic and cerebral hemodynamic and ventilatory responses to different CPT protocols of the hand (CPTH), foot (CPTF), or bilateral feet (CPTBF). We hypothesized CPTBF would elicit greatest physiological responses due to increased exposure area to the cold stimulus. Methods. Twenty-eight (14M;14F) healthy young adults [23.4 (SD: 2.4) years] participated in three 3-minute CPT protocols during a single visit. Mean arterial pressure (MAP), heart rate (HR), middle cerebral artery blood velocity (MCAv) and cerebrovascular conductance index, and end-tidal carbon dioxide (PETCO2), and pain perception were recorded throughout CPT protocols. Results. There was a time-CPT protocol interaction on systolic (p=0.02) and diastolic blood pressure (p<0.01), MAP (p<0.01), HR (p<0.001), presented as mean(SD). MCAv and cerebrovascular conductance index did not change with CPTs. Peak delta HR from baseline occurred in CPTBF (Δ13.6(15.5)BPM) compared to CPTH (Δ4.85(12.6)BPM; p=0.01) and CPTF (Δ4.04(13.3)BPM; p=0.02). Delta MAP was greater in CPTH (Δ12.3(7.95)mmHg) and CPTBF (Δ12.9(9.24)mmHg) compared to CPTF (Δ8.42(7.12)mmHg; p<0.01). Perceived pain was higher in CPTBF compared to single limb protocols (p≤0.01). Conclusion. Our findings suggest choice of limb(s) in CPT protocols affects systemic hemodynamic responses and should be considered when designing CPT studies.
摘要：
冷加压测试（CPT）涉及上肢或下肢的冷水浸泡，并通过刺激疼痛和皮肤热感受器引起自主神经和血液动力学增加。尚不清楚CPT研究中肢体的选择是否会差异影响全身和大脑的血流动力学反应。在这里，我们评估了不同CPT手（CPTH）的全身和脑血流动力学和通气反应，脚（CPTF），或双侧脚（CPTBF）。我们假设CPTBF会由于暴露于冷刺激的面积增加而引起最大的生理反应。方法。在一次访问中，有28名（14M;14F）健康的年轻人[23.4（SD：2.4）岁]参加了三个3分钟的CPT方案。平均动脉压(MAP),心率(HR),大脑中动脉血流速度（MCAv）和脑血管传导指数，和潮气末二氧化碳(PETCO2)，在整个CPT方案中记录疼痛感知。结果。收缩压（p=0.02）和舒张压（p<0.01）存在时间-CPT方案相互作用，MAP（p<0.01），HR（p<0.001），表示为平均值(SD)。MCAv和脑血管传导指数没有随CPT的变化。与CPTH(Δ4.85(12.6)BPM;p=0.01)和CPTF(Δ4.04(13.3)BPM;p=0.02)相比,来自基线的峰值ΔHR出现在CPTBF(Δ13.6(15.5)BPM)中。与CPTF(Δ8.42(7.12)mmHg;p<0.01)相比,在CPTH(Δ12.3(7.95)mmHg)和CPTBF(Δ12.9(9.24)mmHg)中的ΔMAP更大。与单肢方案相比，CPTBF中的感知疼痛更高（p≤0.01）。结论。我们的研究结果表明，CPT方案中肢体的选择会影响全身血液动力学反应，在设计CPT研究时应予以考虑。
