In patients undergoing primary posterior spinal decompression and fusion up to three levels for degenerative lumbar disorders, the use of postoperative drains is not recommended. This is according to a recent multicentre, prospective, randomised controlled clinical trial, the results of which were published online in The Spine Journal by Marcelo Molina (Clínica Las Condes, Santiago, Chile) et al.
The trial found that non-drain patients presented shorter length of stay (LOS), and better outcomes, with similar complication rates, and that there was no difference between body mass index (BMI) and complications.
The researchers note that drains for surgical wound management are frequently used in spine surgery and are often used to decrease both the incidence of postoperative hematoma and wound tension. However, “no conclusive evidence in the literature supports using drains to avoid complications in degenerative lumbar spine surgery”, they add.
The trial aimed to evaluate wound drains in patients with lumbar arthrodesis for degenerative disorders based on clinical outcomes, complications, hematocrit, and LOS.
Surgical candidates for posterior lumbar decompression and fusion surgery for degenerative disorders between October 2019 and August 2021 were enrolled. These patients were then randomised into the drain or non-drain group at nine hospitals.
The inclusion criteria were patients aged 40 to 80 years with lumbar and radicular pain, lumbar degenerative disorder, and primary surgery up to three levels. The exclusion criteria were bleeding abnormalities, bleeding >2500 ml and dural tears.
Preoperative data including Oswestry Disability Index (ODI), SF-36, lumbar and lower extremity Visual Analogue Scale (VAS), BMI, hematocrit and temperature were recorded. Surgical parameters, including surgical time, complications, estimated blood loss (EBL), postoperative temperature and hematocrit (days one and four), dressing saturation, and length of hospital stay, were registered. The two groups were assessed preoperatively, perioperatively and at one-month follow-up.
In total, 101 patients were enrolled using the REDcap database, and 93 patients were evaluated at final follow-up. Forty-five patients were randomised to the drain group, and 48 were randomised to the non-drain group.
The preoperative characteristics were equivalent in both groups: demographic aspects, pain, ODI, SF-36, BMI, hematocrit, and spine pathology. Surgical time, EBL and complications were similar, with no difference between the groups. No difference was found between BMI and complications and no difference was observed in dressing saturation or postoperative temperature between the groups.
The study found that the postoperative day four hematocrit was higher in the non-drain group (36.4% [32–39]) than in the drain group (34% [29.7–37.6]), without statistical difference (p=0.054). The LOS was higher in the drain group (four [three to five] days) than in the non-drain group (three [two to four] days), p=0.007. The quality-of-life score, SF-36, was also found to be higher in the non-drain group (67.9 [53.6–79.2]) than in the drain group (56.7 [49.1–66]), p=0.043.
Speaking to Spinal News International, Molina said: “This is a multicentre, prospective and randomised study with a homogenous population of degenerative lumbar spinal stenosis patients not only in terms of diagnoses, but also in terms of surgical treatment. The inclusion and exclusion criteria in our study were very strict and we tried to answer the research question with a well-designed study with strong evidence.
“We decided to undertake this study because there was not enough evidence in the current literature on this topic. We have seen that in Chile, some doctors use drains and others do not, but nobody has strong evidence to support either choice, even though both groups are able to explain the reasoning behind their choice.”