Electrolyte profile of pediatric patients with hypertrophic pyloric stenosis

Optimizing throughput of babies with infantile hypertrophic pyloric stenosis

BACKGROUND

Definitive surgical care is often delayed in hypertrophic pyloric stenosis (HPS). Our aim is to evaluate the effect modifiable factors in preoperative HPS management have on efficiency of care.

METHODS

A retrospective review of all patients undergoing pyloromyotomy for HPS at two US children's hospitals between 2008 and 2018 was performed.

RESULTS

406 patients were included in the study. The majority (310, 76 ​%) were adequately resuscitated and ready for surgery upon diagnosis in the ER. However, only 133 patients (43 ​%) had surgery on the day of admission. Patients diagnosed between 12pm and 6pm were more likely to have surgery the next day than those diagnosed before noon (67 ​% vs 33 ​%, p ​< ​.001), which correlated with a longer length of stay (32 vs 47 ​h, p ​< ​.001).

CONCLUSION

The majority of patients presenting with HPS can safely undergo same day surgery. Delaying surgery due to an afternoon diagnosis is common, and leads to a modifiable increased total length of stay.

Perioperative Hypoxemia and Postoperative Respiratory Events in Infants with Hypertrophic Pyloric Stenosis

BACKGROUND

 Normalization of metabolic alkalosis is an important pillar in the treatment of infantile hypertrophic pyloric stenosis (IHPS) because uncorrected metabolic alkalosis may lead to perioperative respiratory events. However, the evidence on the incidence of respiratory events is limited. We aimed to study the incidence of peroperative hypoxemia and postoperative respiratory events in infants undergoing pyloromyotomy and the potential role of metabolic alkalosis.

MATERIALS AND METHODS

 We retrospectively reviewed all patients undergoing pyloromyotomy between 2007 and 2017. All infants received intravenous fluids preoperatively to correct metabolic abnormalities close to normal. We assessed the incidence of perioperative hypoxemia (defined as oxygen saturation [SpO2] < 90% for > 1min) and postoperative respiratory events. Additionally, the incidence of difficult intubations was evaluated. We performed a multivariate logistic regression analysis to evaluate the association between admission or preoperative serum pH values, bicarbonate or chloride, and peri- and postoperative hypoxemia or respiratory events.

RESULTS

 Of 406 included infants, 208 (51%) developed 1 or more episodes of hypoxemia during the perioperative period, of whom 130 (32%) experienced it during induction, 43 (11%) intraoperatively, and 112 (28%) during emergence. About 7.5% of the infants had a difficult intubation and 17 required more than 3 attempts by a pediatric anesthesiologist. Three patients developed respiratory insufficiency and 95 postoperative respiratory events were noticed. We did not find a clinically meaningful association between laboratory values reflecting metabolic alkalosis and respiratory events.

CONCLUSIONS

 IHPS frequently leads to peri- and postoperative hypoxemia or respiratory events and high incidence of difficult tracheal intubations. Preoperative pH, bicarbonate, and chloride were bad predictors of respiratory events.

Does Presenting Facility and Race Impact Outcomes and Management of Pyloric Stenosis?

Hypertrophic Pyloric Stenosis (HPS) is a common surgical disease in infants. Traditionally, patients present with projectile emesis and severe dehydration with metabolic alkalosis. We looked to assess if patients presenting as a transfer vs directly to our facility as well as race affected patients' initial presentation and outcomes. We performed a retrospective analysis of 131 patients who presented to with a diagnosis of HPS from 2015 to 2021 assessing how transfer status and patient race affected presenting electrolyte levels and length of stay (LOS). We found no statistically significant difference in patients' presenting electrolyte levels and hospital LOS based on transfer status or patient race. We believe this reflects availability and widespread utility of ultrasound. We suggest that this could be used as a model for standardizing care to equalize outcomes in other pediatric diseases which currently show large disparities in care based on race and geographical location.

Diagnostic Accuracy of Acid-Base Status in Infants with Hypertrophic Pyloric Stenosis

Background: Hypertrophic pyloric stenosis is a condition in newborns in which the hypertrophic pyloric muscle causes gastric obstructive symptoms of progressive vomiting leading to hypochloremic hypokalemic metabolic alkalosis. The main aim of the research was to assess whether, based on the acid-base status, we can distinguish newborns who vomit due to pylorostenosis, compared with newborns who vomit for other unspecific reasons. Methods: The electronic records of patients in the hospital information system treated under the diagnosis Q40.0 (Congenital hypertrophic pyloric stenosis) (n = 69/included in the study = 53) in the period from 1 January 2014 to 1 January 2022 were reviewed retrospectively. For the purposes of the control group, the electronic records of patients treated in the emergency department with a diagnosis of R11.0 (Nausea and vomiting) (n = 53) without an established cause were randomly reviewed. In addition to the main aim, other research outcomes were to determine differences between groups in the following variables: duration of symptoms, family history, birth (preterm, term, post-term), birth weight, weight during examination, difference between birth weight and weight during an examination, type of vomiting, the thickness of the muscle wall and its length, and to calculate whether there is a correlation between the thickness and length of the pylorus muscle and the duration of vomiting in relation to variables from acid-base status. Results: In relation to the variables of interest between the groups, statistically significant differences were observed in the duration of symptoms (Mdn 4 vs. 2 days, p = 0.002), weight at examination (Mean 3880 vs. 4439 g, p = 0.001), difference in weight between birth and examination (Mean 374 vs. 1010 g, p < 0.0001), and type of vomiting (explosive 45 vs. 22, p = 0.023). In the acid-base status between the groups, a statistically significant difference was recorded for pH (Mdn 7.457 vs. 7.422, p < 0.0001), bicarbonate (Mdn 25 vs. 23 mmol/L, p = 0.000), total carbon dioxide (Mdn 25 vs. 24 mmol/L, p = 0.011), base excess (Mdn 0.8 vs. −1.3 mmol/L, p = 0.000), potassium (Mdn 5 vs. 5.3 mmol/L, p = 0.006), ionized calcium (Mdn 1.28 vs. 1.31 mmol/L, p = 0.011), and glucose (Mdn 4.5 vs. 4.9 mmol/L, p = 0.007). Regardless of the group, the correlations between the duration of vomiting (r = 0.316, p = 0.021 vs. r = 0.148, p = 0.290) and the thickness (r = 0.190, p = 0.172) and length (r = 0.142, p = 0.311) of the pylorus muscle in relation to pH did not exist or were weak. Conclusions: In a world where radiological methods are not equally available everywhere, with promising acid-base indicators, prospective multicenter studies and meta-analyses must be pursued in the future in order not to miss the possible much greater diagnostic potential of acid-base status.

Evaluation of a fluid resuscitation protocol for patients with hypertrophic pyloric stenosis

INTRODUCTION

We previously developed an institutional, evidence-based fluid resuscitation protocol for neonates with infantile hypertrophic pyloric stenosis (HPS) based on the severity of electrolyte derangement on presentation. We aim to evaluate this protocol to determine its efficacy in reducing the number of preoperative lab draws, time to electrolyte correction, and overall length of stay.

METHODS

A single center, retrospective review of 319 infants with HPS presenting with electrolyte derangement from 2008 to 2020 was performed; 202 patients managed pre-protocol (2008-2014) and 117 patients managed per our institutional fluid resuscitation algorithm (2016-2020). The number of preoperative lab draws, time to electrolyte correction, and length of stay before and after protocol implementation was recorded.

RESULTS

Use of a fluid resuscitation algorithm decreased the number of infants who required four or more preoperative lab draws (20% vs. 6%) (p < .01), decreased median time to electrolyte correction between the pre and post protocol cohorts (15.1 h [10.6, 22.3] vs. 11.9 h [8.5, 17.9]) (p < .01), and decreased total length of hospital stay (49.0 h [40.3, 70.7] vs. 45.7 h [34.3, 65.9]) (p < .05).

CONCLUSION

Implementation of a fluid resuscitation algorithm for patients presenting with hypertrophic pyloric stenosis decreases the frequency of preoperative lab draws, time to electrolyte correction, and total length of hospital stay. Use of a fluid resuscitation protocol may decrease discomfort through fewer preoperative lab draws and shorter length of stay while setting clear expectations and planned intervention for parents.

LEVEL OF EVIDENCE

III - Retrospective comparative study.

Postoperative apnea after pyloromyotomy for infantile hypertrophic pyloric stenosis

Objective

Infantile hypertrophic pyloric stenosis (IHPS), which causes gastric outlet obstruction and hypochloremic hypokalemic metabolic alkalosis, could pose a risk of postoperative apnea in patients. The aim of this study is to evaluate the incidence of postoperative apnea in babies admitted to a tertiary-level pediatric surgical center in Milano, Italy with diagnosis of IHPS in 2010–2019. The secondary objective is to evaluate the risk factors for postoperative apnea.

Methods

This is a single-center, retrospective, observational cohort study. All patients admitted to our institution with diagnosis of IHPS during the study period were enrolled. Demographic and surgical variables, along with blood gas parameters, were obtained from the population. Postoperative apnea was defined as a respiratory pause longer than 15 s or a respiratory pause lasting less than 15 s, but associated with either bradycardia (heart rate <120 per minute), desaturation (SatO2 <90%), cyanosis, or hypotonia. Occurrence was obtained from nursing charts and was recorded as a no/yes dichotomous variable.

Results

Of 122 patients, 12 (9.84%) experienced apnea and 110 (90.16%) did not. Using univariate analysis, we found that only postoperative hemoglobin was significantly different between the groups (p=0.03). No significant multivariable model was better than this univariate model for prediction of apnea.

Conclusions

Postoperative anemia, possibly due to hemodilution, increased the risk of postoperative apnea. It could be hypothesized that anemia can be added as another apnea-contributing factor in a population at risk due to metabolic changes.

Laparoscopic versus open pyloromyotomies: Outcomes and disparities in pyloric stenosis

PURPOSE

Pyloromyotomy for hypertrophic pyloric stenosis (HPS) is one of the most common non-elective operations performed in the neonatal period. This project aims to explore outcomes of pyloromyotomy and compare differences between laparoscopic versus open pyloromyotomies in newborns diagnosed with HPS.

METHODS

The Nationwide Readmissions Database (NRD) from 2010 to 2014 was queried to identify patients diagnosed with HPS that underwent repair.

RESULTS

In total, 30,915 children (18% female) underwent pyloromyotomy for HPS. Median length of stay for index admission was 2 days. A total of 212 (0.7%) patients required a redo pyloromyotomy. 127 (60%) were performed during index admission. Readmission rate at 30 days was 3% and 5% at one year, and 22% presented to a different hospital. The most common indications for readmission were feeding intolerance (24%), dehydration (10%), and malnutrition (10%). Patients from low-income households were more likely to present with malnutrition and weight loss (9% vs 4%, p<0.001) and had higher readmission rates (8% vs 4%, p<0.001). Laparoscopic pyloromyotomies accounted for 10% (n = 2951) of cases. Those undergoing laparoscopy were less likely to have electrolyte disturbances (41% vs 54%, p<0.001) or weight loss (2% vs 11%, p<0.001) on admission. The rate of open conversion was 1%. Intraoperative perforation was not more common in laparoscopic than open cases. Open pyloromyotomies had higher 30-day readmission rates and more surgical site infections.

CONCLUSION

Complications from pyloromyotomies are rare. Although infrequent, the incidence of incomplete pyloromyotomy is higher than previously reported and more common with open approaches. Newborns from low-income households are more likely to present with advanced symptoms and have disproportionately higher rates of readmission.

LEVEL OF EVIDENCE

Level III TYPE OF STUDY: Treatment Study, retrospective.

Neonatal Community-acquired Raoultella Ornithinolytica Septicemia: A Case Report and Review of the Literature

Raoultella ornithinolytica is an opportunistic, aquaphilic and Gram-negative bacterium. Immune deficiency states and indwelling catheters provide a basis for most of the infections arising. R. ornithinolytica septicemia (ROS) is extremely rare in neonates but can be life threatening. Community-acquired ROS has not been described in neonates before. The diagnosis of neonatal septicemia is occasionally complicated by unusual clinical presentations. Pyloric stenosis is manifested by projectile, nonbilious vomiting and late findings, including weight loss, dehydration and electrolyte abnormalities beyond 4-6 weeks old. Community-acquired neonatal septicemia symptoms can sometimes be confused with symptoms of gastrointestinal obstructions in patients without risk factors for sepsis. Early diagnosis and appropriate antibiotics are essentials for a good prognosis in neonatal septicemia. Herein, we present a novel case of community-acquired ROS with an unusual presentation in a term infant and a review of the literature about ROS in the neonatal period.

The Safety and Effectiveness of Laparoscopic Pyloromyotomy Using 3-mm Electrocautery Hook versus Open Surgery for Treatment of Hypertrophic Pyloric Stenosis in Infants

BACKGROUND

The standard of treatment for infants with hypertrophic pyloric stenosis is still pyloromyotomy. Recently, in most of the pediatric surgery centers laparoscopic pyloromyotomy has become popular. The aim of the present study is to compare the outcomes of treatment in infants with hypertrophic pyloric stenosis between traditional open approach and laparoscopic pyloromyotomy using 3-mm electrocautery hook.

METHODS

A total of 125 infants, 104 (83.2%) males, with median age 33 (interquartile range, IQR 24, 40) days, who underwent pyloromyotomy because of hypertrophic pyloric stenosis, between 2005 and 2021, were included in the retrospective study. Of that number 61 (48.8%) infants were allocated to the open group and 64 (51.2%) to the laparoscopic group. The groups were compared in regards to time to oral intake, duration of surgery, the type and rate of complications, rate of reoperations, frequency of vomiting after surgery, and the length of hospital stay.

RESULTS

No differences were found with regards to baseline characteristics between two investigated groups. Laparoscopic approach was associated with significantly better outcomes compared to open approach: shorter duration of surgery (35 min (IQR 30, 45) vs. 45 min (40, 57.5); p = 0.00008), shorter time to oral intake (6 h (IQR 4, 8) vs. 22 h (13.5, 24); p < 0.00001), lower frequency of postoperative vomiting (n = 10 (15.6%) vs. n = 19 (31.1%)), and shorter length of postoperative hospital stay (3 days (IQR 2, 3) vs. 6 days (4.5, 8); p < 0.00001). In regards to complications and reoperation rates, both were lower in the laparoscopic pyloromyotomy group but the differences were not statistically significant (p = 0.157 and p = 0.113, respectively). The most common complication in both groups was mucosal perforation (open group, n = 3 (4.9%); laparoscopic group, n = 2 (3.1%)) followed by wound infection in open group, n = 3 (4.9%). No cases of wound infection were recorded in the laparoscopic group.

CONCLUSION

Open and laparoscopic pyloromyotomy are equally safe and effective in treatment of hypertrophic pyloric stenosis. Laparoscopic technique is associated with faster recovery, shorter duration of surgery and shorter duration of hospital stay.

Open versus laparoscopic pyloromyotomy for pyloric stenosis

BACKGROUND

Infantile hypertrophic pyloric stenosis (IHPS) is a disorder of young children (aged one year or less) and can be treated by laparoscopic (LP) or open (OP) longitudinal myotomy of the pylorus. Since the first description in 1990, LP is being performed more often worldwide.

OBJECTIVES

To compare the efficacy and safety of open versus laparoscopic pyloromyotomy for IHPS.

SEARCH METHODS

We conducted a literature search on 04 February 2021 to identify all randomised controlled trials (RCTs), without any language restrictions. We searched the following electronic databases: MEDLINE (1990 to February 2021), Embase (1990 to February 2021), and the Cochrane Central Register of Controlled Trials (CENTRAL). We also searched the Internet using the Google Search engine (www.google.com) and Google Scholar (scholar.google.com) to identify grey literature not indexed in databases.

SELECTION CRITERIA

We included RCTs and quasi-randomised trials comparing LP with OP for hypertrophic pyloric stenosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references and extracted data from trial reports. Where outcomes or study details were not reported, we requested missing data from the corresponding authors of the primary RCTs. We used a random-effects model to calculate risk ratios (RRs) for binary outcomes, and mean differences (MDs) for continuous outcomes. Two review authors independently assessed risks of bias. We used GRADE to assess the certainty of the evidence for all outcomes.

MAIN RESULTS

The electronic database search resulted in a total of 434 records. After de-duplication, we screened 410 independent publications, and ultimately included seven RCTs (reported in 8 reports) in quantitative analysis. The seven included RCTs enrolled 720 participants (357 with open pyloromyotomy and 363 with laparoscopic pyloromyotomy). One study was a multi-country trial, three were carried out in the USA, and one study each was carried out in France, Japan, and Bangladesh. The evidence suggests that LP may result in a small increase in mucosal perforation compared with OP (RR 1.60, 95% CI 0.49 to 5.26; 7 studies, 720 participants; low-certainty evidence). LP may result in up to 5 extra instances of mucosal perforation per 1,000 participants; however, the confidence interval ranges from 4 fewer to 44 more per 1,000 participants. Four RCTs with 502 participants reported on incomplete pyloromyotomy. They indicate that LP may increase the risk of incomplete pyloromyotomy compared with OP, but the confidence interval crosses the line of no effect (RR 7.37, 95% CI 0.92 to 59.11; 4 studies, 502 participants; low-certainty evidence). In the LP groups, 6 cases of incomplete pyloromyotomy were reported in 247 participants while no cases of incomplete pyloromyotomy were reported in the OP groups (from 255 participants). All included studies (720 participants) reported on postoperative wound infections or abscess formations. The evidence is very uncertain about the effect of LP on postoperative wound infection or abscess formation compared with OP (RR 0.59, 95% CI 0.24 to 1.45; 7 studies, 720 participants; very low-certainty evidence). The evidence is also very uncertain about the effect of LP on postoperative incisional hernia compared with OP (RR 1.01, 95% CI 0.11 to 9.53; 4 studies, 382 participants; very low-certainty evidence). Length of hospital stay was assessed by five RCTs, including 562 participants. The evidence is very uncertain about the effect of LP compared to OP (mean difference -3.01 hours, 95% CI -8.39 to 2.37 hours; very low-certainty evidence). Time to full feeds was assessed by six studies, including 622 participants. The evidence is very uncertain about the effect of LP on time to full feeds compared with OP (mean difference -5.86 hours, 95% CI -15.95 to 4.24 hours; very low-certainty evidence). The evidence is also very uncertain about the effect of LP on operating time compared with OP (mean difference 0.53 minutes, 95% CI -3.53 to 4.59 minutes; 6 studies, 622 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Laparoscopic pyloromyotomy may result in a small increase in mucosal perforation when compared with open pyloromyotomy for IHPS. There may be an increased risk of incomplete pyloromyotomy following LP compared with OP, but the effect estimate is imprecise and includes the possibility of no difference. We do not know about the effect of LP compared with OP on the need for re-operation, postoperative wound infections or abscess formation, postoperative haematoma or seroma formation, incisional hernia occurrence, length of postoperative stay, time to full feeds, or operating time because the certainty of the evidence was very low for these outcomes. We downgraded the certainty of the evidence for most outcomes due to limitations in the study design (most outcomes were susceptible to detection bias) and imprecision. There is limited evidence available comparing LP with OP for IHPS. The included studies did not provide sufficient information to determine the effect of training, experience, or surgeon preferences on the outcomes assessed.

Respiratory problems owing to severe metabolic alkalosis in infants presenting with hypertrophic pyloric stenosis

OBJECTIVE

Uncorrected metabolic alkalosis in infantile hypertrophic pyloric stenosis (IHPS) could lead to perioperative apnea. However, the precise incidence of preoperative respiratory problems and the association with metabolic alkalosis are unknown. Therefore, we aimed to determine the incidence of preoperative respiratory problems in IHPS and to assess the association with metabolic alkalosis.

METHODS

We retrospectively reviewed all patients diagnosed with IHPS during 2007-2017. Respiratory problems were classified as present or absent. With multivariate logistic regression we analyzed the association between bicarbonate and respiratory problems, corrected for gestational age and birth weight.

RESULTS

We included 459 infants, of whom 23 developed preoperative respiratory problems (5.0%). Infants with preoperative respiratory problems were more often female (43.5% vs. 13.3% p = 0.001) and had significantly higher median serum levels of bicarbonate (32.0 mmol/L vs. 30.0 mmol/L), base excess (6.5 mmol/L vs. 5.3 mmol/L) and pCO2 (6.4 kPa vs. 5.9 kPa), compared to infants without respiratory problems. Multivariate analysis of serum bicarbonate and presence of respiratory problems showed an OR of 2.18 per 10 mmol/L (95% CI 1.21-4.71) (p = 0.009). The optimal bicarbonate cutoff point was 25.7 mmol/L (sensitivity 100%, specificity 13.4%).

CONCLUSION

IHPS with metabolic alkalosis potentially results in preoperative respiratory problems. A lower bicarbonate target before surgery might be recommended and respiratory monitoring should be considered.

LEVEL OF EVIDENCE

Level IV.

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

INTRODUCTION

 Infantile hypertrophic pyloric stenosis (IHPS) is a common gastrointestinal condition that can lead to metabolic alkalosis and, if uncorrected, to respiratory complications. A standardized approach to correct metabolic derangements and dehydration may reduce time until pyloromyotomy while preventing potential respiratory complications. Such an evidence-based policy regarding preoperative care is absent. We aim to formulate a recommendation about preoperative care for infants with IHPS using the Delphi technique.

MATERIALS AND METHODS

 The RAND/UCLA appropriateness method was used to reach international consensus in a panel of pediatric surgeons, pediatric anesthetists, and pediatricians. Statements on type and frequency of blood sampling, required serum concentrations before pyloromyotomy and intravenous fluid therapy, were rated online using a 9-point Likert scale. Consensus was present if the panel rated the statement appropriate/obligatory (panel median: 7-9) or inappropriate/unnecessary (panel median: 1-3) without disagreement according to the interpercentile range adjusted for symmetry formula.

RESULTS

 Thirty-three and twenty-nine panel members completed the first and second round, respectively. Consensus was reached in 54/74 statements (73%). The panel recommended the following laboratory tests and corresponding cutoff values prior to pyloromyotomy: pH ≤7.45, base excess ≤3.5, bicarbonate <26 mmol/L, sodium ≥132 mmol/L, potassium ≥3.5 mmol/L, chloride ≥100 mmol/L, and glucose ≥4.0 mmol/L. Isotonic crystalloid with 5% dextrose and 10 to 20 mEq/L potassium should be used for fluid resuscitation.

CONCLUSION

 Consensus is reached in an expert panel about assessment of metabolic derangements at admission, cutoff serum concentrations to be achieved prior to pyloromyotomy, and appropriate intravenous fluid regime for the correction of dehydration and metabolic derangements in infants with IHPS.

Metabolic profile and outcome of pre- and post-ampullary gastrointestinal obstruction in children: Conventional or unconventional wisdom

BACKGROUND

Conventionally, it is well accepted that the intestinal obstructions in children, especially gastric outlet obstruction are associated with significant metabolic derangement which has impact on its outcome. The study aimed to compare the metabolic profile and treatment outcome of pre- and post-ampullary gastrointestinal obstruction in children at a tertiary care setting.

MATERIALS AND METHODS

A prospective observational study was conducted on 30 children with intestinal obstruction and categorised into Group 1 (pre-ampullary, n = 11) and Group 2 (post-ampullary, n = 19) as per their anatomical site of pathology. Patients were evaluated at both pre- and post-operative period (Day 1 and 10) with haematological, biochemical and blood gas. The pre- and post-operative metabolic profile, resuscitative time and outcome were compared in two groups.

RESULTS

Except mild leucocytosis (Group II > I), rest of the pre-operative and post-operative haematological parameters were within normal range and statistically comparable among groups. Although the pre-operative sodium values were within the normal limit in both groups, it was relatively higher in Group I (Group I = 137.82 ± 4.238 vs. Group II = 134.26 ± 4.653), (P = 0.04). The mean bicarbonate values were within the normal limit in both groups (22.49 and 19.34), but the difference was statistically significant (P = 0.031). Mean partial pressure of carbon dioxide level was higher than normal range in Group I (38.464 ± 20.6493) but was comparable with Group II (P = 0.15). The time required for pre-operative resuscitation was 16.6 versus 24.87 h in Group I versus Group II (P = 0.02). In Group I, all children were improved, whereas four children expired in Group II.

CONCLUSION

Metabolic profile in both pre- and post-ampullary intestinal obstruction was found to be normal in majority of the scenario. Children with post-ampullary obstruction need extensive pre-operative resuscitation and have relatively poor outcome.

Venous Physiology Predicts Dehydration in the Pediatric Population

BACKGROUND

No standard dehydration monitor exists for children. This study attempts to determine the utility of Fast Fourier Transform (FFT) of a peripheral venous pressure (PVP) waveform to predict dehydration.

MATERIALS AND METHODS

PVP waveforms were collected from 18 patients. Groups were defined as resuscitated (serum chloride ≥ 100 mmol/L) and hypovolemic (serum chloride < 100 mmol/L). Data were collected on emergency department admission and after a 20 cc/kg fluid bolus. The MATLAB (MathWorks) software analyzed nonoverlapping 10-s window signals; 2.4 Hz (144 bps) was the most demonstrative frequency to compare the PVP signal power (mmHg).

RESULTS

Admission FFTs were compared between 10 (56%) resuscitated and 8 (44%) hypovolemic patients. The PVP signal power was higher in resuscitated patients (median 0.174 mmHg, IQR: 0.079-0.374 mmHg) than in hypovolemic patients (median 0.026 mmHg, IQR: 0.001-0.057 mmHg), (P < 0.001). Fourteen patients received a bolus regardless of laboratory values: 6 (43%) resuscitated and 8 (57%) hypovolemic. In resuscitated patients, the signal power did not change significantly after the fluid bolus (median 0.142 mmHg, IQR: 0.032-0.383 mmHg) (P = 0.019), whereas significantly increased signal power (median 0.0474 mmHg, IQR: 0.019-0.110 mmHg) was observed in the hypovolemic patients after a fluid bolus at 2.4 Hz (P < 0.001). The algorithm predicted dehydration for window-level analysis (sensitivity 97.95%, specificity 93.07%). The algorithm predicted dehydration for patient-level analysis (sensitivity 100%, specificity 100%).

CONCLUSIONS

FFT of PVP waveforms can predict dehydration in hypertrophic pyloric stenosis. Further work is needed to determine the utility of PVP analysis to guide fluid resuscitation status in other pediatric populations.

Infantile hypertrophic pyloric stenosis - Our experience and challenges in a developing country

BACKGROUND

This study aims to evaluate the experience and challenges in managing patients with infantile hypertrophic pyloric stenosis (IHPS).

PATIENTS AND METHODS

From January 2007 to December 2015, data from patients with IHPS were retrospectively acquired and analyzed using SPSS version 15. Pearson correlation used to assess linear relationships and Student t-test to compare means. P < 0.05 was taken as statistically significant. Results were expressed as percentages, means ± standard deviation and illustrated in tables and graphs.

RESULTS

Twenty-six cases were managed with the mean age at diagnosis of 49.16 ± 21.4 days. Mean birth weight was 3.7 kg and mean weight at presentation was 3.3 kg. Firstborn was affected in 29%; 91% were term deliveries; 9% were post-term; none was preterm; and 36% were exclusively breastfed. Mean duration of symptoms was 25.6 ± 18.9 days. Hyponatraemia was seen in 36%, hypokalaemia 37.5%, alkalosis 35% and hypochloraemia 62%. Mean pyloric tumour length was 22.85 ± 6.56 mm and pyloric wall thickness 5.51 ± 1.36 mm. There was a significant correlation between duration of symptoms and serum potassium level (R = -0.6326, P = 0.002). Mean symptom duration in patients with hypokalaemia was 39.88 ± 23.41 days and without hypokalaemia 17.15 ± 9.78 days (P = 0.006). Mean hospital stay was 9.45 ± 3.27 days. Four patients developed four complications and three patients died (11.5%). Mean age at presentation for pre-operative mortalities was 84 ± 39 days and 46 ± 17.98 days for others (P = 0.015).

CONCLUSIONS

IHPS presents late in our environment and occurs mainly in term males. There is a significant positive relationship between duration of symptoms and serum potassium level and the mean duration of symptoms was significantly longer in those with hypokalaemia. Pre-operative mortality was significantly associated with longer duration of symptoms.

Corrected to uncorrected? The metabolic conundrum of hypertrophic pyloric stenosis

OBJECTIVES

The purpose of this study was to evaluate factors associated with repeat blood testing after establishment of normal metabolic parameters and factors associated with reversal of metabolic correction back an uncorrected form in preoperative management of infants with Hypertrophic Pyloric Stenosis (HSP).

METHODS

A retrospective review of infants with HSP undergoing repeat serum chemistries after already having normal labs were identified. Variables associated with repeating normal bloodwork and reversion of normal to abnormal labs were identified. Associations between reversion to abnormal and ordering of repeat labs were determined.

RESULTS

255 cases were studied with a median of 2 lab tests drawn per patient (range 1-9). Of 142 serum chemistry tests repeated after a normal test, 27% became abnormal, most commonly hyperkalemia. 61% of these went to surgery. No variables were associated with a normal test becoming abnormal. However, a time lapse of >12h was associated with the reordering of bloodwork despite it already being normal.

CONCLUSIONS

There is little evidence to support need for repeat serum chemistry testing in cases of HPS once normality has been established. Development of clinical pathways to reduce the use of unnecessary serum testing may improve efficiency of patient care and limit unnecessary resource utilization.

LEVEL OF EVIDENCE

Retrospective Case control: 3b.

Pediatric Abdominal Pain: An Emergency Medicine Perspective

Abdominal pain is a common complaint that leads to pediatric patients seeking emergency care. The emergency care provider has the arduous task of determining which child likely has a benign cause and not missing the devastating condition that needs emergent attention. This article reviews common benign causes of abdominal pain as well as some of the cannot-miss emergent causes.

Contemporary management of pyloric stenosis

Hypertrophic pyloric stenosis is a common surgical cause of vomiting in infants. Following appropriate fluid resuscitation, the mainstay of treatment is pyloromyotomy. This article reviews the aetiology and pathophysiology of hypertrophic pyloric stenosis, its clinical presentation, the role of imaging, the preoperative and postoperative management, current surgical approaches and non-surgical treatment options. Contemporary postoperative feeding regimens, outcomes and complications are also discussed.

Advances in infantile hypertrophic pyloric stenosis

Infantile hypertrophic pyloric stenosis (IHPS) is a common condition in infancy, characterized by an acquired narrowing of the pylorus, which requires surgery. These infants usually present with projectile, nonbilious vomiting, with a palpable 'olive' in the abdomen and sometimes a 'peristaltic wave' after being fed with formula or breast milk. Although IHPS is a common disorder, its etiology is largely unknown. Surgical intervention is the standard treatment, preoperative preparation, however is essential to optimal outcome. In this review, the latest advances in IHPS regarding epidemiology, etiology, diagnostics and treatment will be discussed.