Ketamine is often be used for sedation and analgesic purpose. It has side effects but often not serious. The following case demonstrated patient who had paralytic ileus post ketamine administration.
A 2-year-old girl with no known comorbid was involved in a motorvehicle accident where she was a pillion rider without helmet; hit by a car. On arrival, primary survery was normal. It was noted her GCS was E4V4M6, pupils 3 mm reactive bilateral with some abrasion wound over left side of the face. Blood pressure 79/50mmHg with pulse rate 154bpm. At same time noted clotted blood at external genitalia. Otherwise abdomen was soft and non tender at this time. Patient was given intravenous ketamine 10mg on titrated dose each time with a total of 100mg over 45mins for gynaecological examination. Gynaecology team review noted there is was right labia minora haematoma but not expanding. Three and half hour later, the mom noted that the patient abdomen becoming more distended. Serial FAST scan noted no free fluid. Chest xray was normal but abdominal xray noted dilated bowel. Patient regained full consciousness later and was admitted for cerebral concussion. She was put on nasogastric tube, kept nil by mouth with intravenous drip. Abdomen distension resolved by itself throughout hospital
stay. Child was discharged well on day 3 post trauma.
Ketamine is the preffered drugs for analgesia as it is considered relatively safe. Beside its analgesic properties, it creates a trance-like state and provides sedation with amnesia, while preserving upper airway and spontaneous breathing. Opiod based drugs when used for analgesic cause more respiratory depression than ketamine. Ketamine is a NMDA receptor antagonist, and also acts on opiod receptors and monoamine transporters. μ-opioid receptor have constipating effects by increasing the tone of intestinal smooth muscle, and reducing propulsion and the strength on contraction. Common complications of ketamine will be emergence reaction, hypersalivation and nausea and vomiting. Rarely paralytic ileus occur post ketamine administration.