Despite becoming a widespread practice, routine use of video laryngoscopy in the ICU is not supported by the evidence. This is the argument made in a recent editorial in JAMA, titled “Video Laryngoscopy in the Intensive Care Unit: Seeing Is Believing, but That Does Not Mean It’s True.”
The editorial, by Brian O’Gara, MD, et al (JAMA 2017 Jan 24. [Epub ahead of print]), comments on the results of a multicenter trial conducted at seven hospitals in France, which was published by Lascarrou et al in the same issue. The trial randomly assigned 371 patients to intubation using either a video laryngoscope (n=186) or direct laryngoscopy (n=185), with all patients receiving general anesthesia.
The trial found no improvement in first-pass intubation rates using video laryngoscopy (67.7%) compared with direct laryngoscopy (70.3%) (absolute difference, <2212>2.5%; 95% CI, <2212>11.9% to 6.9%; P=0.60). Moreover, a post hoc analysis found that video laryngoscopy was associated with more severe life-threatening complications (17 of 179 [9.5%]) compared with direct laryngoscopy (five of 179 [2.8%]) (absolute difference, 6.7%; 95% CI, 1.8%-11.6%; P=0.01). The editorial did stress, however, that the trial was underpowered to definitively demonstrate this association.
Nevertheless, O’Gara et al described the study as “a well-designed and generalizable trial in a complex and clinically important setting—emergency or urgent intubation” and noted that “[more than] 80% of the initial attempts at intubation in the trial were performed by trainees with limited expertise in laryngoscopy, which reflects practice in most academic centers.”
Regarding the association between video laryngoscopy and severe life-threatening complications, the authors of the editorial wrote that “this possible finding should give some pause and mandate inclusion of such complications as prespecified outcomes in future studies of video laryngoscopy.”
Beware of Blind Spots
The editorial authors wrote that the results “illustrate the fundamental problem with video laryngoscopy: it generates excellent views of the larynx but may not facilitate tracheal intubation,” adding that its use “can lead to the creation of blind spots, both visual and cognitive.”
Regarding visual blind spots, the editorial writers noted that the pharynx and hypopharynx are not visualized during video laryngoscopy, since the lens is located on the tip of the device. “Manipulating the endotracheal tube into view therefore occurs within this blind spot, and this can be difficult depending on the patient’s pharyngeal anatomy,” the authors noted. “This phenomenon has been linked to higher rates of pharyngeal soft tissue injury and longer intubation times in patients undergoing video laryngoscopy as compared with direct laryngoscopy.”
Regarding cognitive blind spots, the authors warn that the clear view presented by the video laryngoscope may tempt laryngoscopists in the ICU to continue a laryngoscopy attempt too long, precluding or delaying attempts to reoxygenate or seek other methods of intubation. This, in turn, could result in prolonged apnea time and lead to severe hypoxemia, a finding supported by the results from Lascarrou et al, they wrote.
Daniel Talmor, MD, MPH, Edward Lowenstein Professor and chair in the Department of Anesthesia, Critical Care and Pain Medicine at Beth Israel Deaconess Medical Center and Harvard Medical School, both in Boston, who co-wrote the editorial, said the findings were in line with his expectations.
“Video laryngoscopy was originally designed to assist in difficult intubations, and there is no strong evidence supporting its use in routine intubation, which is what this trial tested,” Dr. Talmor said. “This trial showed no benefit and I was not surprised.
“It’s a good example of how a new and seemingly attractive technology is widely adopted with minimal evidence,” he added, and offered the cautionary tale of the widespread adoption of the pulmonary artery catheter.
The pulmonary artery catheter, Dr. Talmor said, “became almost a symbol of critical care medicine but was, in later studies, shown to not only not benefit, but perhaps increase harm.” Routine use of video laryngoscopy in the ICU may be a “very similar scenario,” he pointed out.