The development of an opioid sparing anesthesia protocol for pediatric ambulatory tonsillectomy and adenotonsillectomy surgery-A quality improvement project.

Pain management following pediatric tonsillectomy and adenotonsillectomy surgery is challenging and traditionally involves perioperative opioids. However, the recent national opioid shortage compelled anesthesiologists at Bellevue Surgery Center to identify an alternative perioperative analgesic regimen that minimizes opioids yet provides effective pain relief. We assembled an interdisciplinary quality improvement team to trial a series of analgesic protocols using the Plan-Do-Study-Act cycle. Initially, we replaced intraoperative morphine and acetaminophen (M/A protocol) with intraoperative dexmedetomidine and preoperative ibuprofen (D/I protocol). However, when results were not favorable, we rapidly transitioned to intraoperative ketorolac and dexmedetomidine (D/K protocol). The following measures were evaluated using statistical process control chart methodology and interpreted using Shewhart's theory of variation: maximum pain score in the postanesthesia care unit, postoperative morphine rescue rate, postanesthesia care unit length of stay, total anesthesia time, postoperative nausea and vomiting rescue rate, and reoperation rate within 30 days of surgery. There were 333 patients in the M/A protocol, 211 patients in the D/I protocol, and 196 patients in the D/K protocol. With the D/I protocol, there were small increases in maximum pain score and postanesthesia care unit length of stay, but no difference in morphine rescue rate or total anesthesia time compared to the M/A protocol. With the D/K protocol, postoperative pain control and postanesthesia care unit length of stay were similar compared to the M/A protocol. Both the D/I and D/K protocols had reduced nausea and vomiting rescue rates. Reoperation rates were similar between groups. In summary, we identified an intraoperative anesthesia protocol for pediatric tonsillectomy and adenotonsillectomy surgery utilizing dexmedetomidine and ketorolac that provides effective analgesia without increasing recovery times or reoperation rates.

Increased nitrite reductase activity of fetal versus adult ovine hemoglobin.

Growing evidence indicates that nitrite, NO2-, serves as a circulating reservoir of nitric oxide (NO) bioactivity that is activated during physiological and pathological hypoxia. One of the intravascular mechanisms for nitrite conversion to NO is a chemical nitrite reductase activity of deoxyhemoglobin. The rate of NO production from this reaction is increased when hemoglobin is in the R conformation. Because the mammalian fetus exists in a low-oxygen environment compared with the adult and is exposed to episodes of severe ischemia during the normal birthing process, and because fetal hemoglobin assumes the R conformation more readily than adult hemoglobin, we hypothesized that nitrite reduction to NO may be enhanced in the fetal circulation. We found that the reaction was faster for fetal than maternal hemoglobin or blood and that the reactions were fastest at 50-80% oxygen saturation, consistent with an R-state catalysis that is predominant for fetal hemoglobin. Nitrite concentrations were similar in blood taken from chronically instrumented normoxic ewes and their fetuses but were elevated in response to chronic hypoxia. The findings suggest an augmented nitrite reductase activity of fetal hemoglobin and that the production of nitrite may participate in the regulation of vascular NO homeostasis in the fetus.