Comparison of Intravenous Ondansetron and Low Dose Ketamine in Preventing Post Spinal Shivering

NCT07334223 | Completed

• 1 other identifier: Mayo1
• Study Type: interventional
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized controlled trial assessed whether intravenous ondansetron is more effective than low dose ketamine in preventing shivering after spinal anesthesia in adults undergoing elective surgery. Post spinal shivering is a frequent and uncomfortable complication of spinal anesthesia and may increase oxygen demand and interfere with routine monitoring. Adults aged 20 to 70 years (body weight 50 to 80 kg; American Society of Anesthesiologists class I to II) scheduled for elective procedures under standardized spinal anesthesia were randomly allocated in equal numbers to receive either ondansetron 8 mg intravenously or ketamine 0.25 mg/kg intravenously, administered 5 minutes after the spinal injection. Perioperative temperature management was standardized for all participants. The primary outcome was the occurrence of post spinal shivering during intraoperative monitoring. Among 180 participants, shivering occurred in 30.0% of those receiving ondansetron and 44.4% of those receiving ketamine, showing a statistically significant reduction with ondansetron.

Conditions

Postoperative Shivering; Postspinal Shivering

Keywords

Spinal anesthesia; Postoperative shivering; Shivering prophylaxis; Ondansetron; Ketamine

Outcome Measures

Primary Outcomes (1)

• Frequency of Post Spinal Shivering

  Occurrence of post spinal shivering following administration of study medication, assessed clinically by the anesthesiology team and recorded as present or absent during intraoperative monitoring after spinal anesthesia.

  From 5 minutes after administration of study drug until transfer of the patient to the post-anesthesia care unit

Study Arms (2)

Group Ondansetron

EXPERIMENTAL

Received 8 mg of ondansetron administered intravenously five minutes after spinal anesthesia for prophylaxis of post spinal shivering.

Drug: ondansetron

Group Low Dose Ketamine

ACTIVE COMPARATOR

Received ketamine 0.25 mg per kilogram administered intravenously five minutes after spinal anesthesia for prophylaxis of post spinal shivering.

Drug: Ketamine (0.25 mg/kg)

Interventions

ondansetron DRUG

8 mg ondansetron administered intravenously as a single dose five minutes after spinal anesthesia.

Also known as: Serotonin type 3 receptor antagonist

Group Ondansetron

Ketamine (0.25 mg/kg) DRUG

0.25 mg per kilogram ketamine administered intravenously as a single dose five minutes after spinal anesthesia.

Also known as: N-methyl-D-aspartate receptor antagonist

Group Low Dose Ketamine

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients of either gender aged 20-60 years with ideal body
• weight of 50 to 80 kg.
• Patients meeting ASA classification I and II determined by
• anesthesiologist.
• Patients undergoing elective surgeries under spinal anesthesia.
• Duration of surgery should not be more than 3 hours.

You may not qualify if:

• Patients having a documented history of severe adverse reactions to ketamine or ondansetron.
• Patients with cardiovascular disease documented in history.
• Patients with hepatic disease documented in history and supported by lab results (AST 32-40U/L), ALT(10-40U/L).
• Patients with renal disease documented in history and supported by lab results. Urea (10-50mg/dl) S/Creatinine (0.3-1.5mg/dl).
• Patients with hyperthyroidism documented in history and supported by lab results.
• Patients with history of mental illness, seizures and glaucoma.
• Patients with known hypertension (BP greater than 140/90).
• Haemodynamically unstable patients (BP\<100mmHg).
• Patients with coagulopathy or other bleeding diathesis documented in history and supported by lab results.
• Complicated prolonged surgeries in spinal anesthesia.

Sponsors & Collaborators

• Mayo Hospital Lahore: lead

Study Sites (1)

Mayo Hospital, Lahore

Lahore, Punjab Province, 54000, Pakistan

Location

MeSH Terms

Interventions

Ondansetron; Ketamine; N-methyl-d-aspartate receptor antagonist MN-08

Intervention Hierarchy (Ancestors)

Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Carbazoles; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds, 3-Ring; Cyclohexanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals

Study Officials

• Adeel Ahmed

  Mayo Hospital Lahore

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 3, 2026
• First Posted: January 12, 2026
• Study Start: January 1, 2020
• Primary Completion: June 30, 2020
• Study Completion: June 30, 2020
• Last Updated: January 12, 2026

Record last verified: 2026-01

Locations

PA (1)