Hypercarbia and high-flow nasal oxygen use during anaesthesia - risking a failure to thrive?

Prevention of arterial oxygen desaturation during anaesthesia with high-flow nasal oxygen (HFNO) has gained greater acceptance for a widening range of procedures. However, during HFNO use there remains the potential for development of significant anaesthesia-associated apnoea or hypoventilation and the possibility of hypercarbia, with harmful cardiovascular or neurological sequelae. The aim of this study was to determine whether any HFNO-related hypercarbia adverse incidents had been reported on webAIRS, an online database of adverse anaesthesia-related incidents. Two relevant reports were identified of complications due to marked hypercarbia during HFNO use to maintain oxygenation. In both reports, HFNO and total intravenous anaesthesia were used during endoscopic procedures through the upper airway. In both, the extent of hypoventilation went undetected during HFNO use. An ensuing cardiac arrest was reported in one report, ascribed to acute hypercarbia-induced exacerbation of the patient's pre-existing pulmonary hypertension. In the other report, hypercarbia led to a prolonged duration of decreased level of consciousness post procedure, requiring ventilatory support. During the search, an additional 11 reports of postoperative hypercarbia-associated sedation were identified, unrelated to HFNO. In these additional reports an extended duration of severe acute hypercarbia led to sedation or loss of consciousness, consistent with the known effects of hypercarbia on consciousness. These 13 reports highlight the potential dangers of unrecognised and untreated hypercarbia, even if adequate oxygenation is maintained.

Patient-controlled analgesia and oral mucositis pain in hematological malignancies.

Oral mucositis (OM) pain is an anticipated complication of immunosuppressive therapies for hematological malignancies. Opioids are effective for OM-associated pain and dysfunction that is refractory to simple measures. At the study institution, parenteral opioids are preferentially prescribed for the treatment of complicated OM. This audit explores the efficacy of opioids for the management of OM pain using morphine, oxycodone, and fentanyl patient-controlled analgesia (PCA). Pain scores, opioid consumption, resumption of oral intake, and the duration of admission were retrospectively analyzed from patient records over an 18-month period. Two-thirds of included patients had ceased PCA therapy by day 6, by which time there was a meaningful 35.4 percent reduction in pain scores, with very few side effects reported. Interagent comparison demonstrated no significant differences in mean daily pain scores; however, a larger sample size would facilitate an investigation of clinically significant nuances in treatment differences, if they exist.

Opioids in acute pain: Towards getting the right balance.

Misuse of prescription opioids forced an inevitable response from authorities to intervene with consequences felt by all.In the Australian community one person will die for approximately every 3600 adults prescribed opioids, while in the hospital setting a postoperative patient managed primarily with opioids, as opposed to epidural analgesia, has an additional risk of death as high as between one in 56 to 477.Opioids maintain a valid role in acute pain management when use is reasoned and with full awareness of the harms and how they are to be avoided, such as in those at risk of ongoing use, the opioid naïve, and when opioid-induced ventilatory impairment may occur.Clinicians managing acute pain can focus on assessing pain versus nociception, strategically apply antinociceptive medications and neural blockade when indicated, assess pain with an emphasis on the degree of bothersomeness and functional impairment and, finally, optimise the use of framing and placebo-enhancing communication to minimise reliance on medications.

Clinical implications of opioid-induced ventilatory impairment.

Opioid-induced ventilatory impairment is the primary mechanism of harm from opioid use. Opioids suppress the activity of the central respiratory centres and are sedating, leading to impairment of alveolar ventilation.Respiratory physiological changes induced with acute opioid use include depression of the hypercapnic ventilatory response and hypoxic ventilatory response. In chronic opioid use a compensatory increase in hypoxic ventilatory response maintains ventilation and contributes to the onset of sleep-disordered breathing patterns of central sleep apnoea and ataxic breathing. Supplemental oxygen use in those at risk of opioid-induced ventilatory impairment requires careful consideration by the clinician to prevent failure to detect hypoventilation, if oximetry is being relied on, and the overriding of hypoxic ventilatory drive. Obstructive sleep apnoea and opioid-induced ventilatory impairment are frequently associated, with this interrelationship being complex and often unpredictable. Monitoring the patient for opioid-induced ventilatory impairment poses challenges in the areas of reliability, avoidance of alarm fatigue, cost, and personnel demands. Many situations remain in which patients cannot be provided effective analgesia without opioids, and for these the clinician requires a comprehensive knowledge of opioid-induced ventilatory impairment.

Management of postsurgical pain in the community.

Following surgery there is often a need for ongoing pain management after the patient is discharged from hospital. This can be made easier if the patient has an appropriate discussion before leaving hospital about what pain they can expect, and they are given a management plan Paracetamol and non-steroidal anti-inflammatory drugs are suitable for most patients. Drugs with a short half-life, such as ibuprofen, may need to be taken regularly Short-acting opioids can have a short-term role, providing guidelines are followed. There is a predictable period of time after surgery when the benefit of an opioid is expected to be maximised before harmful adverse effects will dominate Gabapentinoids are useful for neuropathic pain, but have a limited role in nociceptive pain. Like opioids, they have a risk of misuse The surgeon should be consulted if the patient develops new pain or the postoperative pain becomes more severe Most postsurgical pain will resolve within three months. If not, it is deemed persistent pain that may warrant specialist assessment

Is femoral nerve block necessary during total knee arthroplasty?: a randomized controlled trial.

There remains a lack of randomized controlled trials comparing methods of perioperative analgesia for total knee arthroplasty. To address this deficiency, a blinded, randomized controlled trial was conducted to compare the use of femoral nerve block (group F) and local anesthetic (group L). A sample of 55 patients who met the inclusion criteria were randomized to either group. No significant differences in the most severe pain score or 36-Item Short Form Health Survey, The Western Ontario and McMaster Universities Arthritis Index (WOMAC), or Oxford scores were observed between groups. However, the Knee Society score was significantly higher in group F. In addition, group F used significantly fewer micrograms of intravenous fentanyl in the first 24 hours. Balancing the risks of femoral nerve block with those of increased systemic narcotic delivery should be performed on a case-by-case basis.