الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
LC is a minimally invasive procedure and one of the most common operations that has gained worldwide acceptance as standard surgery for gallstones disease. It is usually performed under general anaesthesia. It does not require cutting of abdominal muscles, resulting in less pain, quicker healing, improved cosmetic results, and fewer complications such as infection and adhesions. Most patients can be discharged on the same or the following day of surgery and can return to any type of occupation in about a week. It can be done by multiple incisions or by single incision through the umbilicus. These patients often recover faster than traditional methods, and have an almost invisible scar.
Spinal anaesthesia is a less invasive technique and has less complications and mortality rates compared with general anaesthesia. It provides intraoperative analgesia and muscle relaxation in conscious and compliant patients without any systemic drugs that makes it preferred in patients with liver or kidney diseases. It avoids the risks of hypoxia or hypercapnia accompanied with general anaethesia. It also provides potent postoperative analgesia with a lesser consumption of systemic opioid than general anaesthesia.
At the same time, spinal anaesthesia may be associated with complications. The most common complications are hypotension and bradycardia. Hypotension after spinal anaesthesia is initially due to a blockade of sympathetic fibers leading to a DROP in systemic vascular resistance. Spinal-induced bradycardia is multifactorial but is in part due to the Bezold-Jarisch Reflex. This reflex is mediated by serotonin receptors within the wall of the ventricle in response to systemic hypotension. These receptors, the 5HT3 subtype, cause an increase efferent vagal signaling when bound by serotonin released during hypovolemic states, clinically leading to bradycardia and further hypotension.
Ondansetron is a serotonin 5-HT3 receptor antagonist used to prevent nausea and vomiting caused by cancer chemotherapy, radiation therapy and surgery. It also has off-label use for treatment of hyperemesis gravidarum. It has been safely used to blunt the Bezold-Jarisch Reflex, resulting in less bradycardia and hypotension first in animals and later in humans undergoing spinal anesthesia.
The aim of this work was studying the effects of ondansetrone for reduction of spinal analgesia induced hypotension in LC.
Patients and Methods:
After approval of the local ethics committee and an informed written consent from each patient, the current study was carried out in Alexandria Main University Hospital on 40 patients undergoing LC under spinal anaesthesia; in a prospective, randomized study. The sample size was determined by High Institute of Public Health, Biostatistics Department. Inclusion criteria: Patient of American Society of Anesthetists (ASA) physical status I or II, operations lasting from one to two hours. Exclusion criteria: Patients with contraindications to spinal anaesthesia, (Patient refusal, low fixed cardiac output states, infection at or near site of injection and neurological deficit), history of hypersensitivity to ondansetron or local anaesthetic agents, patients receiving selective serotonin reuptake inhibitors or migraine medications and those who were converted to general anaesthesia.
Patients were divided randomly into two groups:
Group I: patients received intravenous ondansetron 4 mg diluted in 10 mL of normal saline over 1 min, 5 min before spinal anaesthesia.
Group II: patients received intravenous normal saline 10 mL over 1 min, 5 min before spinal anaesthesia.
Preoperative evaluation of the patients was carried out through proper history taking and clinical examination routine laboratory investigations. A peripheral 18-gauge i.v. cannula was inserted. All patients received Ringer’s solution 10 mL/kg given over 30 min as a preload. They were divided into two groups as mentioned before. Standard monitoring was established using a multichannel monitor Drager infinity vista xl, Germany. After injection of the studied solution by five minutes, patients were placed in the sitting position and skin was prepared with betadine 10%. At the puncture site, 2 ml of 2% lidocaine were injected subcutaneously. The puncture was performed at L2-3 interspace using a 25 gauge Quinke spinal needle and injection of 3ml of 0.5% hyperbaric bupivacaine plus 0.5 ml fentanyl (25µg). After injection, patients were in the supine position till the level of sensory block reached T4. When the sensory block reached T4 dermatome and Bromage score 3 ( patient can not flex ankles, knees or hips ) surgery was allowed to start. Sedation was given in the form of 4 – 6 mg nalbuphine. Oxygen by face mask was given at 6 L/min throughout the procedure. Intraoperative fluid infusions were calculated and given according to body weight. Surgery was started by small incision at the umbilicus through which abdominal cavity was entered. The surgeon inflated the abdominal cavity by low pressure pneumoperitoneum (<12 mmHg) with carbon dioxide to create a working space. The camera was placed through the umbilical port and the abdominal cavity was inspected. Additional ports were opened inferior to the ribs at the epigastric, midclavicular, anterior, axillary positions through which surgery was done.
Measurements:
The following demographic data were measured for each patient: age (years), sex (male / female), weight (kg) and duration of the operation (minutes). Haemodynamic measurements included; heart rate, mean arterial blood pressure and arterial oxygen saturation. These parameters were measured before and immediately after intrathecal injection and then at 5, 10, 15 minutes, and then every 15 minutes till the end of the procedure, then hourly for six hours postoperatively. End tidal carbondioxide was measured by a capnomask before intrathecal injection, immediately after injection and then every 15 minutes till the end of the procedure. Nausea and vomiting score was assessed every 15 minutes till the end of the procedure and then hourly for six hours postoperatively. Sedation was estimated using Ramsey sedation scale every 15 minutes till the end of the procedure and then hourly for six hours postoperatively. Patient and surgeon satisfaction were assessed at the end of the procedure at the recovery room using patient and surgeon satisfaction scores. Complications for example: respiratory depression, shoulder pain, PDPH, nausea and vomiting, chest pain, pruritis and hypersensitivity reaction were reported and properly treated.
Results:
As regard demographic data: There were no significant differences between the two groups as regards age (P=0.644), sex (P = 0.749), weight (P = 0.629) and duration of the operation (P = 0.852).
As regard heart rate changes; in group I it decreased insignificantly at 10, 15, 30, 45, 60, 75, 90, 105 and 120 minutes after intrathecal injection and after 1, 2, 3 and 6 hours postoperatively. In group II, it decreased significantly at 30, 45, 60, 75 and 90 minutes after intrathecal injection. It decreased insignificantly immediately and at 5, 10, 15, 105 and 120 minutes after intrathecal injection and at 1, 2, 3 and 6 hours postoperatively.
Comparison between the two studied groups revealed that heart rate was significantly lower in group II than in group I at 5, 10, 15, 30, 45, 60, 75, 90, 105 and 120 minutes after intrathecal injection and at one hour postoperatively. There were no other significant differences between the two groups.
As regard mean arterial blood pressure (MABP); in group I, it decreased insignificantly immediately and 5 minutes after intrathecal injection. It decreased significantly after 10, 15 and 30 minutes after intrathecal injection. There were no other significant changes throughout the times of measurement intra or postoperatively. In group II, it decreased insignificantly immediately and 5 minutes after intrathecal injection. It decreased significantly after 10, 15, 30, 45, 60 and 75 minutes after intrathecal injection. There were no other significant changes throughout the times of measurement intra or postoperatively. Comparison between the two studied groups revealed that; there were no significant differences between the two groups immediately and at 5 minutes after intrathecal injection. It was significantly lower in group II than in group I at 10, 15, 30, 45, 60, 75, 90, 105 and 120 minutes after intrathecal injection. There were no significant differences in the postoperative period.
As regard arterial oxygen saturation, in group I and II there was no significant change in intraoperative or postoperative periods compared to preoperative readings. Comparison between the two studied groups revealed that; there was no significant difference through intraoperative and postoperative periods.
As regard end tidal carbondioxide (etco2), in group I it increased significantly at 15, 30, 45, 60, 75, 90, 105 and 120 minutes after intrathecal injection. In group II it increased significantly at 15, 30, 45, 60, 75, 90, 105 and 120 minutes after intrathecal injection. Comparison between the two studied groups revealed that; there was no significant difference between the two groups throughout the whole intraoperative period.
As regard incidence of nausea and vomiting, in group I, there were no significant changes intra and postoperatively. In group II it increased significantly at 15, 30, 45 and 75 minutes after intrathecal injection. It also increased significantly at 1, 2, 3 and 4 hours postoperatively. Comparison between the two studied groups revealed that nausea and vomiting score was significantly higher in group II than in group I at 15, 45 and 75 minutes after inrtathecal injection intraoperatively and at 5 hours postoperatively. There were no other significant differences between the two groups intra and postoperatively.
As regard sedation score, in group I, It decreased significantly at 45, 60, 90, 105 and 120 minutes after intrathecal injection. It also decreased significantly at 1, 2, 3, 4, 5 and 6 hours postoperatively. In group II, It decreased significantly at 60, 75, 90, 105 and 120 minutes after intrathecal injection. It also decreased significantly at 1, 2, 3, 4, 5 and 6 hours postoperatively. Comparison between the two studied groups revealed that, there was no significant difference in the whole period of operation and in the postoperative period.
As regard patient satisfaction score, in group I, 45% of patients were extremely satisfied, 40% were satisfied and 15% were neither satisfied nor dissatisfied. In group II, 20% were extremely satisfied, 30% were satisfied, 30% were neither satisfied nor dissatisfied and 20% were dissatisfied. Comparison of the two studied groups revealed that it was significantly higher in group I than in group II.
As regard surgeon satisfaction score, in group I, 50% of surgeons were extremely satisfied, 40% were satisfied and 10% were neither satisfied nor dissatisfied. In group II, 15% were extremely satisfied, 35% were satisfied, 45% were neither satisfied nor dissatisfied and 5% were dissatisfied. Comparison of the two studied groups revealed that, it was significantly higher in group I than in group II.
As regard complications, in group I 10% of patients had shoulder pain and there was no incidence of respiratory depression, chest pain, postdural puncture headache (PDPH), pruritis or urine retention. In group II 5% had shoulder pain, 5% had PDPH and there was no incidence of respiratory depression, chest pain, pruritis or urine retention. Comparison of the two studied groups revealed that; there were no significant differences in incidence of complications.
Conclusions:
LC can be performed under spinal anaesthesia, whenever indicated, without significant side effects. Intravenous ondansetron (4mg) decreases the incidence of spinal induced hypotension and bradycardia. Premedication with intravenous ondansetron (4mg) decreases the incidence of nausea and vomiting significantly intra and postoperatively.