Letters to the Editor: Letters & Announcements
To the Editor
We applaud Hua et al.1 for their use of a quality registry to generate the unplanned intubation risk index (UIRI), because postoperative tracheal reintubation carries a 20-fold increase in hospital mortality. However, the value of clinical outcome registries lies not solely in identifying the sickest patients as anesthesiologists readily appreciate the risk of tracheal reintubation in septic, elderly, ASA physical status III/IV, and/or patients undergoing prolonged surgery. Of greater importance, however, is that whereas prospective studies are typically underpowered to detect infrequent events because of insufficient sample size, clinical registries can identify covariates influencing risk in patients considered “low risk” for adverse events. Unexpected deaths during hospitalization of “low risk” patients disproportionately involve patient safety incidents that are potentially preventable and amenable to continuous process improvement.2 Reintubation in a low-risk patient may be attributed to potentially preventable causes, such as incomplete or omitted antagonism of prolonged neuromuscular blockade, negative pressure pulmonary edema, opioid administration, hyperventilation, overhydration, or tracheal extubation, before the patient attains a sustainable patent airway or adequate minute ventilation.
We applied the UIRI of Hua et al. to 368,785 adult patients receiving general anesthesia in our North American Partners in Anesthesia registry (January 2010–May 2012). Three hundred sixty-eight patients (0.1%) required tracheal reintubation within 48 hours of surgery, 143 of whom (39%) were deemed low risk by UIRI. This group disproportionately accounted for 68% of patients for whom “naloxone use,” “negative pressure pulmonary edema,” “aspiration,” or “prolonged neuromuscular blockade” were listed as the likely cause for tracheal reintubation, all amenable to continuous process improvement, unlike the UIRI main risk factors of sepsis, ASA physical status, age, or surgery duration. With the current focus on reducing preventable morbidity and mortality, clinical registries will increase the likelihood of exposing risk and reducing preventable adverse events in low-risk patients.
Frank J. Overdyk, MSEE, MD
Department of Anesthesiology
Hofstra North Shore-LIJ School of Medicine
New Hyde Park, NY
Peter F. R. Walker, MD
North American Partners in Anesthesia (NAPA)
Melville, New York
1. Hua M, Brady JE, Li G. A scoring system to predict unplanned intubation in patients having undergone major surgical procedures. Anesth Analg. 2012;115:88–94