Serum electrolytes and capillary blood gases in the management of hypertrophic pyloric stenosis

Abstract

The purpose of this study was to assess whether the concentration of serum chloride and other variables, namely serum sodium, potassium and bicarbonate, can be used to predict metabolic acid-base status in infants with hypertrophic pyloric stenosis (HPS) and to assess whether such a prediction is influenced by the state of hydration. One hundred and sixty-three infants with HPS who had at least one set of serum electrolyte and capillary blood gas estimations performed after admission were studied retrospectively. A further 25 infants who had their electrolyte and blood gases measured after at least 12 h of rehydration and correction of the serum sodium and chloride abnormalities were studied prospectively. Stepwise multiple regression analysis, using standard bicarbonate as the dependent variable, revealed serum chloride concentration to be the most powerful independent predictor of standard bicarbonate level (r = -0.69, P less than 0.0001). Other variables did not improve the correlation significantly. In the retrospective study of untreated patients, the calculation of a 90 per cent prediction interval for the model indicated that if the serum chloride level is less than 96 mmol/l, one could be 95 per cent confident (one tail) that the patient was alkalaemic. To be 95 per cent confident that the patient was not alkalaemic, the serum chloride level would have to be greater than 121 mmol/l. The prospective study found that following rehydration a serum chloride level greater than or equal to 106 mmol/l more accurately predicted absence of alkalaemia. We conclude that predictability of acid-base status from measurement of serum chloride depends on the state of hydration of the patient.

Pathophysiology of Hypertrophic Pyloric Stenosis Revisited: The Use of Isotonic Fluid for Preoperative Infusion Therapy Is Supported

“…These results correspond to those of a previous study [16]. Others described a slow decline in Na + concentration as the symptoms persisted [13] and a negative correlation between the Na + and 3 HCO − levels [15]. In a recent Chinese study, hyponatremia was found in 54% of infants with IHPS [8].…”

“…However, these mechanisms appear to be less important in infants [24]. In concordance with the results of a previous study [15], a correlation analysis confirmed a strong negative correlation between st 3 HCO − and K + (p = 0.001, Table 4). In our cohort, we predominantly found a highly normal serum K + concentration, and less than 10% of the infants had values below 3.5 mmol/l.…”

“…The OSM calculated using the standard formula was 280 ± 9.19 mmol/l (280; 269 -290). Using the improved formula, which is described elsewhere [15], we found 283 ± 10.4 mosm/kg.…”

Implementation of a care pathway for infantile hypertrophic pyloric stenosis reduces length of stay and increases parent satisfaction

“…12 Additionally, 12-hourly blood sampling was thought to be the most appropriate by the parents within the consensus committee. Previous authors have described reductions in duration of hospitalization by using standardized post-pyloromyotomy feeding regimens.…”

A Delphi Analysis to Reach Consensus on Preoperative Care in Infants with Hypertrophic Pyloric Stenosis

“…2,6,8,13 Adequate resuscitation is reported as plasma chloride concentration >106 mmol/L in some studies, while others suggest chloride >100 mmol/L or even >97 mmol/L as sufficient prior to surgery. 4,[13][14][15][16] These variabilities in cutoff values also exist for other laboratory variables. To correct metabolic alkalosis and electrolyte disturbances, fluid resuscitation is needed.…”