Surgery at Night Twice as Deadly as During the Day

A new five-year study shows that patients who have surgery during the night are twice as likely to die as patients operated on during regular working hours.

Researchers at McGill University Health Centre (MUHC, Montreal, Canada) and the Jewish General Hospital (Montreal, Canada) conducted a retrospective review of all surgical procedures from April 1, 2010, to March 31, 2015, at JGH. The researchers constructed a database of variables about surgical interventions and 30-day postoperative in-hospital mortality, evaluating all elective and emergent surgical cases, except ophthalmic and local anesthesia cases. The working day was divided into three time blocks; daytime (07:30-15:29), evening (15:30-23:29), and night time (23:30-07:29).

In all 41,716 elective and emergency surgeries were performed on 33,942 patients, of which 10,480 were emergency procedures. In all, there were 226, 97, and 29 deaths of all cases during day, evening and night surgery. After adjustment, the patients operated in the night were 2.17 times more likely to die than those operating on during regular daytime working hours, and patients operated on in the late day were 1.43 times more likely to die than those operated on during daytime working hours. The study was presented at the annual World Congress of Anesthesiologists (WCA), held September-October 2016 in Hong Kong (China).

“Postoperative 30-day in-hospital mortality rate should include start time of anesthesia, along with other known variables, as a risk factor,” concluded study lead author Michael Tessler, MD, and colleagues of the department of anesthesia, “Theoretical possible causes include, but are not limited to, provider fatigue during anesthesia and surgery, overnight hospital staffing issues, delays in treatment, or the patient being too sick to be postponed prior to treatment.”

The results are supported in part by a 2014 study conducted by researchers from Tohoku University (Japan), who reviewed data from 72 different studies covering more than 55 million patients worldwide, which concluded that the so-called “weekend effect” on hospital death rates is international, and the most likely explanation for the results was poorer quality care at weekends.

Related Links:
McGill University Health Centre
Jewish General Hospital
Tohoku University