Testing the Feasibility of Using Ropivacaine in Spinal Anesthesia for Patients With Lower Back Surgery

Number of patients contacted who accepted or declined to participate in the study, with the acceptance rate calculated as the percentage of contacted patients who agreed to participate in the study

Number of patients who complete the study after randomization, with the completion rate calculated as the percentage of randomized patients in whom we were able to collect the Quality of Recovery-15 survey results

Reasons why the patient, neurosurgeon and/or anesthesiologist refused to proceed with the patient's pilot study participation

Number of participants who actually get the intervention assigned to them, calculated as the percentage of randomized patients who receive the anesthetic protocol assigned to them

Similarity of the groups on their baseline characteristics based on the demographic information

Assessing for dermatome level at which the patient has normal sensation to ice and pinprick, at specific intervals (every 2 minutes after spinal anesthesia up to 10 minutes or until thoracic level between T10 and T6 is achieved (whichever is later); on arrival to PACU; every 30 minutes after arrival to PACU until discharge to the ward or home).

whether the patient is able to sense nothing, touch, or pain at time of first incision

assess for muscle strength at specific intervals (every 5 minutes up to 10 to 20 minutes after spinal anesthesia, on arrival to PACU (postanesthetic recovery unit), and every 30 minutes after arrival to PACU until discharge to the ward or home).

preoperatively; intraoperatively; on arrival to PACU (postanesthetic recovery unit); at discharge from PACU to the ward or home; 24 hours after surgery. Measure: numerical rating scale (0 to 10, with 10 being excruciating pain)

Total dosage of opioids and other analgesics (i.e., acetaminophen, NSAIDs) administered to the participant during surgery, and over 24 hours after surgery, as measured using milligrams

total duration of time (in minutes) with mean arterial pressure (MAP) below 65

total duration of time (in minutes) with heart rate below 55

total dose of vasopressors used intraoperatively, as measured in milligrams

Percentage of participants in the spinal anesthesia group who successfully complete their lower back surgery without additional interventions (including conversion from spinal anesthesia to general anesthesia, additional analgesics through the intravenous line, additional spinal anesthesia medication dose given by the neurosurgeon, additional numbing medication infiltrated in the surgical incision by the neurosurgeon)

by the number of patients who had spinal anesthesia who then had to be converted to general anesthesia or not complete surgery

As measured in minutes, the time it takes to: from entering the operating room to the receiving the general anesthesia or spinal anesthesia medication, to the participant being in surgical position (lying on his/her stomach), to achieve sensory level of dermatomal level between T10 and T6 (numbness to ice and pinprick)

Whether the neurosurgeon found operating on the spine to be more or less challenging under spinal anesthesia, in comparison to his or her previous experience with general anesthesia. This will be measured on a 5-point Likert scale, from "significantly less challenging" to "significantly more challenging".

Whether the neurosurgeons would recommend doing lumbar spine surgery under spinal anesthesia as a feasible anesthetic option, measured on a 5-point Likert scale (from "very likely" to "very unlikely")

Whether the operating room nurses would recommend doing lumbar spine surgery under spinal anesthesia as a feasible anesthetic option, measured on a 5-point Likert scale (from "very likely" to "very unlikely")

Operating room nurses' workload when helping with a spine surgery conducted under spinal anesthesia, compare to when helping with a spine surgery done under general anesthesia. . This would be measured on a 5-point Likert scale, from "significantly less work (compared to GA)" to "significantly more work (compared to GA)"

Whether the PACU nurses would recommend having lumbar spine surgery done under spinal anesthesia as a feasible anesthetic option, measured on a 5-point Likert scale (from "very likely" to "very unlikely")

Postanesthetic care unit nurse (PACU) nurses' workload when taking care of a patient post-operatively from a spine surgery done under spinal anesthesia, compared to if the spine surgery had been done under general anesthesia. This would be measured on a 5-point Likert scale, from "significantly less work (compared to GA)" to "significantly more work (compared to GA)".

Graded as 1 attempt, 2 attempts, ≥3 attempts, abandoned attempt, or no attempt made (i.e. general anesthesia).

Anesthesiologists' workload when doing the spine surgery under spinal anesthesia, in comparison to general anesthesia. This would be measured on a 5-point Likert scale, from "significantly less work (compared to GA)" to "significantly more work (compared to GA)".

Patients' experience during the administration of spinal anesthesia (inserting a needle into the back) in terms of pain tolerability. This will be assessed using the numerical rating scale (NRS). The NRS is a clinically used, validated scoring system ranging from 0 (no pain) to 10 (severe, excruciating pain

Patients' comfort during the surgery if they received a spinal anesthetic. This will be assessed using the NRS (described above). There will also be 2 other options to choose from in case the patient is unable to report the pain level using the numerical rating scale (NRS), including "Patient does not remember", and "N/A (patient was in general anesthesia group)".

Whether patients who had spinal anesthesia remembered what happened during surgery. There will be 2 options: "Yes, I remember", and "No, I do not remember".

For patients who had spinal anesthesia, they are asked whether they were bothered by the weakness and/or numbness in the legs in the PACU

The patients are asked if, prior to surgery, they had a preference for general anesthesia or spinal anesthesia. There will be three options: "I would prefer general anesthesia", "I would prefer spinal anesthesia", and "I have no preference".

QoR-15 (Quality of Recovery) score, done 24 hours after surgery, covers a range of items including ease of breathing, enjoyment of food, feeling rested, sleep quality, able to do personal hygiene unaided, communication with friends and family, able to return to work and usual home activities, feeling of being in control, overall general well-being, pain levels, nausea or vomiting, anxiety, and depression. It is scored out of 150, with a higher score signifying better quality of recovery.

Whether assessing the sensory and motor blocks by 10 to 20 minutes after spinal anesthesia is long enough to determine whether the spinal anesthesia dose has achieved a minimum sensory level to dermatomal level between T10 and T6 to ice and pinprick. We will thus be monitoring the time it takes to achieve this level (measured in minutes) as noted above.

Drop in hemoglobin will be measured as a percentage in hemoglobin drop, as calculated by the preoperative hemoglobin minus the postoperative hemoglobin on postoperative day 1, then divided by the preoperative hemoglobin

Aggregate of complications (percentage of patients) who had issues during surgery (estimated blood loss (millilitres), incidence of low blood pressure (mean arterial pressure less than 65), incidence of low heart rate (less than 55), incidence of interventions to treat low blood pressure and/or low heart rate)

Incidence of common side effects at 24 hours after surgery from spinal anesthesia or general anesthesia, including headache, nausea, vomiting, pruritus, dizziness, blurred vision, urinary retention, numbness or tingling in the upper extremities, sore throat, as well as any other side effects not mentioned

Incidence of complications after surgery and up to discharge from hospital (headache after surgery, delirium or confusion, urinary retention requiring a Foley bladder catheter, need to return to the operating room for emergency re-operation, spinal hematoma, worsening nerve injury).

Worsening in neurological symptoms at 24 hours after surgery