Interarm blood pressure difference in acute hemiplegia

Is the blood pressure different between the paralyzed and unaffected arms or legs?

OBJECTIVES

To investigate whether the blood pressure (BP) levels are similar between the paralyzed and unaffected arms or legs.

METHODS

This study enrolled 236 post-stroke patients with hemiplegic paralysis. Simultaneous four-limb BP was measured using four automatic BP devices for three times, and the average was used as final value. The inter-arm difference (IAD) and inter-ankle difference (IAND) were the BP difference between the arms or ankles, respectively. The difference between maximal BP reading and minimal BP reading was calculated as △BP to reflect the variation of three BP readings.

RESULTS

The paralyzed arm had similar mean SBP (134.8 ± 18.7 vs. 135.1 ± 19.0 mmHg, NS) and DBP (79.5 ± 11.3 vs 78.1 ± 10.4 mmHg, NS) levels as compared with the unaffected arm. Similarly, the mean ankle SBP (143.6 ± 19.1 vs. 143.7 ± 18.6 mmHg, NS) and DBP (77.9 ± 17.7 vs. 75.8 ± 11.1 mmHg, NS) in the paralyzed legs were also similar to those in the unaffected legs. The detection rate of systolic IAD ≥10 mmHg was 5.9% and that for systolic IAND ≥15 mmHg was 20.3%. Meanwhile, △SBP levels were similar between two arms or ankles.

CONCLUSION

In the post-stroke patients with hemiplegic paralysis, the SBP and DBP levels of the paralyzed and unaffected arms or ankles were similar.

Prevalence and clinical implications of the inter-arm blood pressure difference: a systematic review

A blood pressure (BP) difference between arms was first reported over 100 years ago. Knowledge of its prevalence and relevance to the accurate measurement of BP remains poor. Current hypertension guidelines do not emphasise it. The objectives of this study were to establish the best estimate of prevalence of the inter-arm difference (IAD) in the population, to consider its implications for accurate BP measurement and treatment, and to discuss its aetiology and potential as a risk marker for cardiovascular disease. Systematic literature review was carried out. The data sources were Medline EMBASE and CINAHL databases, and Index of Theses. Studies reporting prevalence rates of IAD were retrieved and considered for inclusion against explicit methodological criteria. Point prevalence rates were extracted and weighted mean prevalence rates calculated. The main outcome measures were weighted mean prevalences of systolic IAD > or =10 and > or =20 mm Hg and of diastolic IAD > or =10 mm Hg. Thirty-one studies were identified. Most had methodological weaknesses; only four met the inclusion criteria. Pooled prevalences of the IAD from these four studies were 19.6% systolic > or =10 mm Hg (95% CI 18.0-21.3%), 4.2% systolic > or =20 mm Hg (95% CI 3.4-5.1%) and 8.1% diastolic > or =10 mm Hg (95%CI 6.9-9.2%). In conclusion, an IAD is present in a substantial number of patients and should be looked for whenever diagnosis and treatment depend on accurate measurements of BP. The importance of an IAD should be better emphasised in current hypertension management guidelines. There is evidence associating an IAD with peripheral vascular disease, raising the possibility that its presence may predict cardiovascular events.

The cold hemiplegic arm

BACKGROUND AND PURPOSE

Vasomotor changes occur in the arm after hemiplegic stroke. Previous studies have provided conflicting results, with most showing an increase in skin temperature of the hemiplegic arm. However, a number of patients complain of distressing coldness of the hemiplegic arm.

METHODS

Eleven patients with symptomatic coldness and 10 patients with hemiplegia but no coldness were recruited. The severity of the symptom of coldness was compared by questionnaire with other common symptoms after stroke. A thermographic camera was used to record the finger skin temperature response to cold stress. Blood flow to both hands was also measured simultaneously by means of two plethysmographs. In all patients there were no symptoms in the unaffected arm, and this was used as a control.

RESULTS

The symptom of coldness rated highly compared with other symptoms. In the symptomatic group the finger temperature on the hemiplegic side was lower at rest (median difference at rest, 0.65 degrees C; P < .0001) and at all times after cold stress. In the asymptomatic group the fingers on the hemiplegic side were colder at rest and after initial cooling (median temperature difference, 0.2 degrees C) but at no other time. Hand blood flow on the hemiplegic side was also decreased in the symptomatic group by 35%. This was not seen in the asymptomatic group.

CONCLUSIONS

Coldness of the hand may be a severe and distressing symptom in some patients after hemiplegia. Symptomatic patients have lower finger skin temperatures at rest and after standard cold stress. These symptomatic patients also had reduced blood flow to the hemiplegic hand.