Читать книгу Practical Pediatric Gastrointestinal Endoscopy - Группа авторов - Страница 42

Before the administration of medications, a baseline set of vital signs should be documented. The name, route, site, time, and dosage of all drugs administered should be recorded. Once medication administration has begun, level of consciousness and vital signs should be documented on a time‐based flow sheet every five minutes. The vital signs documented should include heart and respiratory rate, oxygen saturation, and blood pressure. Once the procedure is complete and no more medications are to be administered, vital signs should be documented every 15 minutes until the child awakens.

Whether administration of medications is performed by the gastroenterologist or the sedation practitioner, good communication is crucial in order to provide optimal procedural sedation. It is important in order to anticipate physiologic changes or the conclusion of the procedure, which could affect a decision to administer a dose of medication or not. Timing of medication administration should be predicated on anticipating patient responses, which is best performed by maintaining an awareness of the procedure through observation and communication. It is the responsibility of the individual monitoring the patient to alert the gastroenterologist to physiologic deterioration, and to temporarily stop the procedure if rescue measures are required.

The nature of gastrointestinal endoscopy mandates a discussion of the specific physiological considerations inherent to the procedure. For example, esophageal intubation can induce apnea and bradycardia due to stimulation of the laryngeal branch of the vagus nerve. Infants or children with spastic neuromuscular disorders are especially prone to this, due to their small size and high cricopharyngeal tone, respectively. When air is insufflated into the gastrointestinal tract, it has the potential to cause respiratory insufficiency. Excess air in the stomach can elevate the left hemidiaphragm, impeding respiratory excursion and subsequently tidal volumes, which can be deleterious for ventilation and oxygenation. The loss of functional residual capacity can subsequently cause hypoxemia from loss of alveolar recruitment, and positive pressure ventilation, along with gastric decompression, may be necessary to recover adequate oxygen saturation.

Mesenteric stretch can cause various degrees of abdominal discomfort in some individuals, and adequate analgesia is needed to blunt this response. Intense pain during a colonoscopy, for example, is a sign of excessive mesenteric stretching and requires not only adequate analgesia but immediate adjustment of endoscopic technique. This situation highlights the need for constant communication between the gastroenterologist and monitor, as adjustments must be made by both individuals for the best procedural conditions.

The issue of standard supplemental oxygen use is controversial. Due to the nature of the procedure, supplemental oxygen is often needed to maintain adequate oxygen saturations. It must be kept in mind that failure in ventilation may be masked by supplemental oxygen, due to the law of partial pressures in the alveoli.