Capillary blood collection in haematology

Abstract

SYNOPSIS A capillary blood collection technique which facilitates the estimation of routine haematological parameters, including platelet count and sedimentation rate, is described. The technique requires 05 ml of blood, allows closer reproducibility than pipette collection methods, is suitable for monitoring blood counts in patients receiving cytotoxic agents, and can be integrated with semiand fully-automated production lines.The ability to collect capillary blood from thumb or heel is essential in paediatric haematology. Capillary blood specimens for routine blood tests are usually collected into several individual pipettes and the appropriate dilutions made at the bedside (Brecher, Schneiderman, and Cronkite, 1953;Lewis and Benjamin, 1965;Dacie and Lewis, 1968;Brecher, 1971). This is time consuming and can be technically difficult, particularly when the child is in an incubator. When the specimens reach the laboratory they may require to be processed separately from the semi-and fully-automated production lines used for venous blood. A major disadvantage of pipette collection and dilution at the bedside is that additional tests cannot be performed, or an abnormal test result repeated, without a return visit to the patient.A simplified collection technique in which 0 5 ml of capillary blood is taken directly into a single plastic container is described. A micro-method for estimation of the erythrocyte sedimentation rate (ESR) on the same blood sample has been developed simultaneously.

Lack of prominent compensatory polycythemia in traditional native andeans living at 4,200 meters

“…Venipuncture was not used as there was strong reluctance and fear on the part of the Quechua to having blood drawn. However, no significant differences in the results from the two methods (finger puncture and venipuncture) have been reported (Fahey et al, 1977;Moe, 1970;Stuart et al, 1974).…”

Blood Coagulation Measurements Using Dynamic Speckle Technique

“…This experimental set-up is an improvement of the former one employed in a previous paper [15]. Samples corresponding to 14 volunteers were extracted under general biosecurity protocols [17] and according to standards of protection of human patients [18] they were assigned a code and analyzed. Each sample consists of 50 microliters of blood which were extracted from the pad of the middle finger of the left hand.…”

Comparison of venous and capillary blood sampling for the clinical determination of tobramycin serum concentrations.

“…The advent of microvolume analytical techniques makes it possible to assay small volume capillary samples, collected by a finger lancet puncture. Capillary sampling has been used interchangeably with venous sampling for the determination of theophylline (Frazer et al, 1983), phenytoin (Umstead & McKernon, 1981), and various biochemical and haematological parameters (Blumenfield et al, 1977;Stuart et al, 1974). However, significant venous-arterial concentration differences have been identified with a number of other drugs (Chiou & Lam, 1982) (Schentag et al, 1978), studies in rabbits have demonstrated that tobramycin distributes slowly into interstitial fluid with peak concentrations attained 34 h after peak concentrations in serum (Gerding et al, 1976;Carbon et al, 1978).…”