The effect of local cooling on digital systolic pressure in patients with Raynaud's syndrome

Abstract

The effect of local controlled cooling on the digital systolic blood pressure in the hand was studied in 25 In an effort to make objective measurements in patients with primary or secondary Raynaud's syndrome, several workers have studied blood flow in the hand ( I , 2) before and after local cooling, blood viscosity ( 3 ) changes at low temperatures and photoelectric measurement of pulse amplitude (4) during stepwise cooling. Nielsen ( 5 ) suggested that photoplethysmography was unsuitable for detecting pulsation when finger systolic pressure was less than 30-40mmHg. He described a method (5,6) of indirectly measuring finger systolic pressure at different temperatures using a proximal occluding cuff and a proximal cooling cuff, and strain gauge plethysmography to detect distal pulsation. However, although Nielsen achieved objective pressure measurements that separated normals from patients with primary Raynaud's disease (5,7), he found it necessary to use body cooling with a cooling blanket at an ambient room temperature of 22°C to achieve this separation. We have adopted his method of local finger cooling, using photoplethysmography instead of strain gauge plethysmography to detect distal pulsation. and a lower ambient room temperature of 17.5-18 "C instead of total body cooling. The aim of our study was to measure and attempt to identify any difference in the response to cooling in controls and patients with Raynaud's syndrome. Patients and methodsTwenty-five normal volunteers (21 women, 4 men: age 20-40 years) acting as controls and 25 patients (20 women, 5 men: age 22-67 years) with Raynaud's syndrome were studied. Seven patients had systemic sclerosis. 2 had Buerger's disease and in 14 the diagnosis was unknown. In each subject the brachial systolic blood pressure and the systolic blood pressure of the cooled middle finger and of the noncooled (reference) index finger were measured. This was achieved using a thermostatically controlled culT, which could be pressurized and simultaneously perfused with water at 30°C or 10°C. on the middle digit. a non-cooled cuff pressurized by air at ambient room temperature on the index finger and photoplethysmographic (PPG) probes to detect the distal pulse on the tip of each finger. A commercially available digit cooling machine (Medimatic, Copenhagen, Denmark) was used. Both cuffs were capable of being pressurized and deflated simultaneously; cuff pressure was monitored via an Akers transducer (AE 840) and amplifier and recorded on a pen recorder (Watanabe MC611). The PPG probes (Medasonics PH77). placed on the pulp of each digit, were connected via a Photo Pulse Adaptor (Medasonics PA13) and the tracings were recorded on the same pen recorder. Thus, there were simultaneous recordings of cuff pressure and distal pulses.The pre-test conditions for all subjects involved no tobacco or alcohol (in the preceding 2 hours) and a light meal only, and for the test all were rested for 20 minutes in light clothing at a room temperature maintained at 17.5-18 "C. Cuffs on both fing...

Effect of prior exposure to hand-transmitted vibration on cold response of digital arteries

“…This finding is consistent with the results of other studies of the repeatability of FSBP measurements in which the coefficient of variation for repeated determinations of FSBP% at 6 or 10°C was found to average between 5 and 13% in either normal individuals or vibration-exposed workers [8,16,23].…”

A longitudinal study of finger systolic blood pressure and exposure to hand-transmitted vibration

“…These discriminating thresholds between normal and pathological responses of the digital arteries to cold provocation are broadly consistent with those suggested by other authors who reported lower normal limits of 58-66% at 6 or 10°C in smaller samples of male controls (Bovenzi 2002;Ekenvall and Lindblad 1986;Hoare et al 1982;Nielsen et al 1980;Olsen et al 1982). It is worth noting that the lower normal limits for FSBP% 10°i n the asymptomatic HTV workers of this study were 63% at the basal testing and 55% at the follow-up, after excluding the subjects who showed the closing phenomenon of digital arteries after cold provocation.…”

“…Previous studies of cold provocation in normal men were of cross-sectional type (Bovenzi et al 1998;Carnicelli et al 1993;Ekenvall and Lindblad 1986;Olsen et al 1982). In these studies, the reproducibility or repeatability of FSBP indices after cooling varied from 5 to 13% in either normal individuals or HTV workers (Carnicelli et al 1993;Hoare et al 1982;Olsen et al 1982). This range of values is consistent with the results of our previous investigation on the repeatability of FSBP measurements in which the coefficient of variation for repeated measures of FSBP% 10°i n five healthy men average 6% (range 3.8-9.2%) (Bovenzi 2002).…”

Quantifying digital vascular disease in patients with primary Raynaud's phenomenon and systemic sclerosis

“…62-65 67 68Methodological and patient population differences between studies may be relevant. In a large and detailed study including controls, “cold sensitive” subjects, patients with PRP, and patients with SSc spectrum disorders, Maricq et al have shown that digital blood pressure responses to temperature change have high sensitivity and specificity in distinguishing between patients with SSc spectrum disorders and PRP, and between patients with PRP and cold sensitive individuals 60…”