Spinal Anesthesia Leads to Fewer Post-operative Complications, Small Study Suggests

Spinal anesthesia may be safer than general anesthesia for people with Parkinson’s disease undergoing surgery, causing fewer post-operative complications, including a risk of death, a small study suggests.

The study, “Spinal versus General Anesthesia for Patients with Parkinson’s Disease,” was published in the International Journal of General Medicine.

Anesthesia temporarily blocks nerve sensation, making it indispensable for many surgeries although its use carries known risks. For people with nervous system damage or impairment, as occurs in Parkinson’s, these known risks are greater.

Few studies, however, have looked at the safety of different types of anesthesia used in surgeries for people with Parkinson’s.

Researchers at the Jordan University of Science and Technology addressed this knowledge gap by analyzing hip surgeries given to 10 Parkinson’s patients at their care center between 2015 and 2018. They evaluated each person’s medical history, the type of anesthesia used, and post-surgical complications.

“Anesthesiologists prefer using general anesthesia (GA) given that PD [Parkinson’s] is a neurological disease,” the team wrote. “However, GA may mask neurological symptoms in the intraoperative period and exacerbate them postoperatively. Furthermore, the anesthetics used in GA have clear interactions with the drugs used to control PD.”

These eight men and two women had an average age of 73.2 (range, 57–90 years old) with disease stages of 3 or 4 on the Modified Hoehn and Yahr Scale, meaning mild-to-moderate (stage 3) and severe disability.

Nine had a history of previous falls, and all were undergoing surgery for a broken hip (neck-of-femur fractures). Two of these 10 patients had evidence of neurological symptoms like psychosis (“mental illness,” according to the study), and hypertension was  the most common comorbidity (co-existing illness). All but one had normal blood pressure at the time of surgery.

Six were given spinal anesthesia (SA) and the other four received general anesthesia. Spinal anesthesia involves injecting medicines into the spinal canal to numb the body from the waist down; general anesthesia can either be delivered as an intravenous injection (directly into the vein) or as a gas, and results in a state of controlled unconsciousness.

No postoperative complications were reported in the six people given  spinal anesthesia while two of the four on general anesthesia were later admitted to the intensive care unit for collapsed lungs, and a third developed a urinary tract infection.

On average, patients who received spinal anesthesia were discharged after 5.8 days. Those given general anesthesia remained in the hospital for an average of nine days, as they required more monitoring.

Pneumonia was reported after discharge by one spinal anesthesia patient, but the researchers noted this person had a history of swallowing problems at the time of admission. Three out of the four people on general anesthesia had post-discharge complications, including deep vein thrombosis (DVT), stroke, pneumonia (largely, aspiration pneumonia), low blood cell counts, and seizures. One, who had both pneumonia and seizures after surgery, died after leaving the hospital.

“Our results revealed that SA poses less risk on such patients compared with GA,” the researchers concluded. “This was mainly demonstrated in the postoperative course since both groups had similar preoperative baseline characteristics and no intraoperative complications were detected.”

Their study also noted that harmful interactions between the levodopa Parkinson’s patients use to treat motor symptoms, and anesthetic medicines can be difficult to avoid. This is particularly true of general anesthesia, where certain medicines like thiopental can lower dopamine release. A case report documents a patient experiencing severe and prolonged dystonic muscle rigidity after surgery using thiopental.

A major concern with using general anesthesia is that it can mask certain Parkinson’s symptoms such as tremors and rigidity, of which the surgeon needs to be aware.

Regional anesthesia, such as spinal anesthesia, carries fewer postoperative side effects and requires less time off of levodopa, the study noted. Spinal anesthesia also lowers the probability of experiencing aspiration pneumonia, respiratory weakness, urinary tract infection, DVT, postural hypotension, and psychiatric crises.

Regional anesthesia, however, may not be the option in all cases, they added. Compared to general anesthesia, patient positioning can be more complicated, and tremors may interfere with aspects of the surgery. Because spinal anesthesia leaves the patient awake during surgery, special attention must be given to the airways, to ensure ease of communication in the event of a sudden onset of Parkinson’s symptoms.

Still, their findings suggests that spinal anesthesia may be the safer option to general anesthesia, causing fewer serious post-operative complications. Further and larger studies, however, are necessary.