Association of Wearable Derived Pulse Rate Variability With Pediatric Appendectomy Complications.

INTRODUCTION: Postoperative recovery of children is difficult to gauge by parents after hospital discharge. Consumer wearable devices (CWD) generate valid and near real-time pulse rate data, integer pulse rate variability (PRVi), that can serve as digital biomarkers for the onset of complications during post-discharge recovery. This study sought to explore whether pediatric patients with surgical complications after appendectomy exhibited a CWD-derived PRVi trajectory that differs from the normative PRVi recovery trajectory. METHODS: In this retrospective analysis, children aged 3-17 undergoing appendectomy for complicated appendicitis was invited to participate. Participants wore a Fitbit device for 21 days postoperatively. PRVi was calculated as the variance, defined as the sum of the squared differences of each value from the mean, of the heart rate in beats per minute measured over 5 consecutive minutes. The mean daily PRVi was calculated for patients recovering with and without complications. RESULTS: Ninety-eight patients were enrolled in the study; 60 (61 %) were ages 3-11, 54 (55 %) were female, and 57 (58 %) were Caucasian. Eleven (11 %) developed surgical complications. Those with complications experienced a slower increase in the mean PRVi over the 21-day period. CONCLUSIONS: In this prospective observational study, it was demonstrated that PRVi derived from CWD data can be used as an objective digital biomarker to profile surgical complications. This finding provides clinicians with an additional tool for monitoring children during the postoperative period, enhancing their ability to proactively detect and address complications. LEVEL OF EVIDENCE: IV.

Step cadence as a novel objective postoperative recovery metric in children who undergo laparoscopic appendectomy.

BACKGROUND: Daily step counts from consumer wearable devices have been used to objectively assess postsurgical recovery in children. However, step cadence, defined as steps taken per minute, may be a more specific measure of physiologic status. The purpose of this study is to define objective normative physical activity recovery trajectories after laparoscopic appendectomy using this novel metric. We hypothesized that patients would have a progressive increase in peak cadence until reaching a plateau representing baseline status, and this would occur earlier for simple compared with complicated appendicitis. METHODS: Children aged 3 to 18 years were enrolled after laparoscopic appendectomy for simple or complicated appendicitis between March 2019 and December 2022 at a tertiary children's hospital. Participants wore a Fitbit for 21 postoperative days. The peak 1-minute cadence and peak 30-minute cadence were determined each postoperative day. Piecewise linear regression was conducted to generate normative peak step cadence recovery trajectories for simple and complicated appendicitis. RESULTS: A total of 147 children met criteria (53.7% complicated appendicitis). Patients with simple appendicitis reached plateau postoperative day 10 at a mean peak 1-minute cadence of 111 steps/minute and a mean peak 30-minute cadence of 77 steps/minute. The complicated appendicitis recovery trajectory reached a plateau postoperative day 13 at a mean peak 1-minute cadence of 106 steps/minute and postoperative day 15 at a mean peak 30-minute cadence of 75 steps/minute. CONCLUSION: Using step cadence, we defined procedure-specific normative peak cadence recovery trajectories after laparoscopic appendectomy. This can empower clinicians to set data-driven expectations for recovery after surgery and establish the groundwork for consumer wearable devices as a post-discharge remote monitoring tool.

Soybean-derived recombinant human epidermal growth factor protects against experimental necrotizing enterocolitis.

BACKGROUND: Epidermal Growth Factor (EGF) reduces necrotizing enterocolitis (NEC). However, its high cost virtually prohibits clinical use. To reduce cost, soybean expressing human EGF was developed. Here we report effectiveness of soybean-derived EGF in experimental NEC. METHODS: Newborn rats were subjected to the NEC-inducing regimen of formula feeding and hypoxia. Formula was supplemented with extract from EGF-expressing or empty soybeans. NEC pathology was determined microscopically. Localization of tight junction proteins JAM-A and ZO-1 was examined by immunofluorescence and levels of mucosal COX-2 and iNOS mRNAs by real time PCR. RESULTS: Soybean extract amounts corresponding to 150µg/kg/day EGF caused considerable mortality, whereas those corresponding to 75µg/kg/day EGF were well tolerated. There was no significant difference in NEC scores between animals fed plain formula and formula supplemented with empty soybean extract. Soybean-EGF-supplemented formula at 75µg/kg/day EGF significantly decreased NEC, attenuated dissociation of JAM-A and ZO-1 proteins from tight junctions, and reduced intestinal expression of COX-2 and iNOS mRNAs. CONCLUSION: Supplementation with soybean-expressed EGF significantly decreased NEC in the rat model. Soybean-expressed EGF may provide an economical solution for EGF administration and prophylaxis of clinical NEC.