Risk factors associated with unplanned ICU admissions following paediatric surgery: A systematic review

Background. Unplanned admissions to the intensive care unit (ICU) have important implications in the general management of patients. Research in this area has been conducted in the adult and non-surgical population. To date, there is no systematic review addressing risk factors in the paediatric surgical population. Objective. To synthesise the information from studies that explore the risk factors associated with unplanned ICU admissions following surgery in children through a systematic review process. Method. We conducted a systematic review of published literature (PROSPERO registration CRD42020163766), adhering to the Preferred Reporting of Observational Studies and Meta-Analysis (PRISMA) statement. The Population, Exposure, Comparator, Outcome (PECO) strategy used was based on: population – paediatric population, exposure – risk factors, comparator – other, and outcome – unplanned ICU admission. Data that reported on unplanned ICU admissions following paediatric surgery were extracted and analysed. Quality of the studies was assessed using the Newcastle-Ottawa Scale. Results. Seven studies were included in the data synthesis. Four studies were of good quality with the Newcastle-Ottawa Scale score ≥7 points. The pooled prevalence (95% confidence interval) estimate of unplanned ICU stay was 2.69% (0.05 - 8.6%) and ranged between 0.06% and 8.3%. Significant risk factors included abnormal sleep studies and the presence of comorbidities in adenotonsillectomy surgery. In the general surgical population, younger age, comorbidities and general anaesthesia were significant. Abdominal surgery and ear, nose and throat (ENT) surgery resulted in a higher risk of unplanned ICU admission. Owing to the heterogeneity of the data, a meta-analysis with risk prediction could not be performed. Conclusion. Significant patient, surgical and anaesthetic risk factors associated with unplanned ICU admission in children following surgery are described in this systematic review. A combination of these factors may direct planning toward anticipation of the need for a higher level of postoperative care. Further work to develop a predictive score for unplanned ICU stay is desirable

Porous silicon gas sensing

In this chapter, the state of the art on porous silicon gas sensors, both electrical and optical, is reviewed by paying special emphasis on the advancement of gas sensor architectures that has occurred over the two last decades, as well as on the different functionalization approaches implemented in and chemical species sensed with such architectures. Ten main architectures, five for the electrical domain (capacitor, Schottky-like diode, resistor, FET-like transistor, and junction-like diode) and five for the optical domain (single layer, waveguide, Bragg mirror, resonant cavity, and rugate filter), have been proposed so far for improving gas sensor features. Several functionalization schemes have been integrated in such architectures to improve sensor performance, and more than 50 different chemical species have been sensed using porous silicon gas sensors. The latest trends on multiparametric sensing on single devices as well as on multisensor integration in a single chip, for both optical and electrical domains, are also discussed

Porous Silicon Micromachining Technology

In this chapter, silicon electrochemical micromachining (ECM) technology is reviewed with particular emphasis to the fabrication of complex microstructures and microsystems, as well as to their applications in optofluidics, biosensing, photonics, and medical fields. ECM, which is based on the controlled electrochemical dissolution of n-type silicon under backside illumination in acidic (HF-based) electrolytes, enables microstructuring of silicon wafers to be controlled up to the higher aspect ratios (over 100) with sub-micrometer accuracy, thus pushing silicon micromachining well beyond up-to-date both wet and dry microstructuring technologies. Both basic and advanced features of ECM technology are described and discussed by taking the fabrication of a silicon microgripper as case study