Length-based body weight estimation in paediatric patients: The impact of habitus-A clinical observational trial

Paediatric emergency tapes provide drug dosing based on the patient's estimated body weight. Unfortunately, published data revealed an unsatisfactory accuracy. A newly developed digital algorithm for weight estimation (CLAWAR) allowing a three-staged habitus adaptation (normal, obese, or cachectic; CLAWAR-3) demonstrated a higher accuracy for weight estimation compared to paediatric emergency tapes. However, the incidence of incorrectly evaluated habitus was 27%. A five-staged habitus adaptation with figural images was suggested by Wells et al to improve habitus and weight estimation. Therefore, CLAWAR was modified with five habitus stages including figural images (CLAWAR-5). We hypothized CLAWAR-5 improves the accuracy of weight estimation.

After obtaining informed written parental consent patients were included in this single centre, prospective clinical observation trial. Body weight estimations by CLAWAR-3 and CLAWAR-5 within ±10% of the actual body weight were compared. Furthermore, the incidence of correct evaluated habitus was calculated. McNemar Tests were used for statistical analysis. Results presented as median (interquartiles), P < .003 considered significant.

In total, 312 patients aged 3.3 years (0.7-6.6), with a body length of 95.9 cm (70.0-121.2), weighing 14.8 kg (8.1-22.5), were included. Both CLAWAR-3 and CLAWAR-5 showed equivalent accuracy for weight estimation within the ±10% interval (62.2% vs 60.6%, P = .609). Despite adding figural images, the incidence of correct evaluated habitus with CLAWAR-5 (46.8%) was worse than with CLAWAR-3 (66.7%).

The five-staged habitus-adapted method could not improve the accuracy of weight estimation. Furthermore, the error rate of habitus classification was not reduced by the implementation of figural images.