Predicting Covid-19 pandemic waves with biologically and behaviorally informed universal differential equations

During the COVID-19 pandemic, it became clear that pandemic waves and population responses were locked in a mutual feedback loop in a classic example of a coupled behavior-disease system. We demonstrate for the first time that universal differential equation (UDE) models are able to extract this interplay from data. We develop a UDE model for COVID-19 and test its ability to make predictions of second pandemic waves. We find that UDEs are capable of learning coupled behavior-disease dynamics and predicting second waves in a variety of populations, provided they are supplied with learning biases describing simple assumptions about disease transmission and population response. Though not yet suitable for deployment as a policy-guiding tool, our results demonstrate potential benefits, drawbacks, and useful techniques when applying universal differential equations to coupled systems.

Complications of continuous epidural infusions for postoperative analgesia in children

To determine the incidences of side effects and complications associated with the use of epidural analgesia for infants and children at the Alberta Children's Hospital, we reviewed our experience over a two-year period. A database was established for recording management, side effects and complications of each epidural, and this is a retrospective review of that database. Problems were identified as complications if there was a need for medical intervention related to the patient complaint, and if the intervention was documented in the patient record. Continuous epidural analgesia with bupivacaine 0.125% or bupivacaine 0.1% with epinephrine was used for managing postoperative pain in 190 children with mean age 5.6 yr (range 1 mo to 18 yr) and the mean weight 22 kg (range 4-88 kg). Mean duration of the epidural infusions was 4.7 days (range 1-16 d). In 127 patients, 203 complications were recorded. Complications, in order of frequency, were nausea and vomiting (23% of patients), motor blockade (15.8% of patients), over-sedation (6.3% of patients), and pruritus (5.2% of patients). Four patients had complications which were potentially related to toxic effects of, or resistance to, bupivacaine, and serum levels of bupivacaine were measured at 3.86, 5.5, 2.1 and 2.34 micrograms.ml(-1). Early discontinuation of the epidural occurred in 41 cases, technical problems with the epidural catheter being the commonest reason (21 cases). Although three potentially serious complications were identified (one catheter site infection, one seizure, one respiratory depression) none was associated with lasting consequences. The majority of complications associated with the use of epidurals were minor and easily remedied.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaesthetic management of an asthmatic child for appendicectomy

A 13-yr-old boy was scheduled for emergency appendicectomy because of abdominal pain. His preoperative medical history was complicated by a recent hospital admission for management of asthma. He had presented to hospital seven days earlier because of dyspnoea, tachypnoea and oxygen desaturation to 77% on room air. Following admission, he required intensive nonventilatory management of his asthma, including intravenous salbutamol, methylprednisolone, and aminophylline, as well as use of an ipratroprium bromide inhaler and 100% oxygen by mask. He was discharged to the ward, and continued on prednisone (delta-cortisone), beclomethasone inhaler, ipratroprium inhaler, and salbutamol inhaler. During his ICU stay, he complained of nonspecific abdominal pain, interpreted as gastro-oesophageal reflux. After four days, he was discharged to the ward. On his sixth hospital day, he began to experience right-sided lower abdominal pain and right shoulder pain. A surgeon was consulted, and the patient was found to have a very tender right lower quadrant with guarding and rebound pain. He was therefore scheduled for appendicectomy; antibiotic therapy with ampicillin, gentamicin, and metronidazole was initiated.