Impact evaluation of two different general anesthesia protocols (TIVA with propofol vs isoflurane) on the total number of interventions to treat cardiovascular depression or arousal/movement episodes in dogs undergoing orthopedic surgery receiving an intrathecal anesthesia

Abstract

The aim of this prospective, randomized clinical trial was to compare the total number of anesthetic interventions (TNAI) performed by the anesthetist to treat cardiovascular depression or arousal/movement episodes in dogs receiving intrathecal and general anesthesia (GA), maintained using propofol-based TIVA (group P) or isoflurane (group I). Mean arterial pressure (MAP) before (T0) and 12 min after intrathecal anesthesia (T1) and intraoperative vasoactive consumption were also compared. The TNAI to deepen the anesthetic plane or to treat hemodynamic depression in the pre-surgical and intra-surgical period was calculated in forty-two client-owned dogs randomly assigned to group P or I. Ten dogs for each group complied with the inclusion criteria and were analyzed. In pre-surgical period, the TNAI was higher in Group I [2 (0–5)] than Group P [0 (0–2)] (P=0.022), and ephedrine consumption was also higher in Group I [75 (0–200) µg/kg)] than Group P [(0 (0–50)] (P=0.016). MAP (mmHg) in Group P was 79 (66–95) at T0 and 65 (59–86) at T1 and 67.5 (50–73) and 57 (53–66) in Group I, respectively. At T0 and T1, MAP was higher in Group P (P=0.005 and P=0.006, respectively). No differences were found between the two groups in the intrasurgical period (P>0.05). This study shows that the GA protocol can have a relevant impact on the TNAI performed by the anesthetist in the pre-surgical period of anesthesia, to treat cardiovascular depression or arousal/movement episodes in dogs receving intrathecal anesthesia.

Thoracic epidural anaesthesia vs intrathecal morphine in dogs undergoing major thoracic and abdominal surgery: clinical study

“…The prolonged permanence of hydrophilic morphine in the CSF allows it to spread cranially to the cerebrum and cause sedation. The morphine dosage we administered has been used in previous studies for many various surgical procedures, mainly for controlling perioperative orthopaedic pain [30][31][32] which reported no postoperative sedation. It is difficult to explain why postoperative prolonged sedation occurred in about 10% of cases.…”

“…One dog received 25 μg/kg of fentanyl during prolonged surgery (140 min), which may have resulted in a certain degree of accumulation, given that intrathecal morphine has been reported to reduce the need for fentanyl [25]. Nevertheless, more data on spinal analgesia in dogs are needed, considering that postoperative monitoring in previous studies was short and that the dogs were adult animals undergoing orthopaedic surgery [30][31][32]. Ours is the first study to report on the use of intrathecal morphine in old dogs with cancer.…”

Effect of fentanyl constant-rate infusions with or without medetomidine on the minimum infusion rate of propofol required to prevent motor movement in dogs

“…Propofol provides a rapid onset and a short duration of anesthetic effect, which are desirable qualities of an injectable anesthetic agent for use in total intravenous anesthesia (TIVA) in dogs [ 9 ]. Compared with inhalational anesthetic agents such as isoflurane, propofol has been reported to maintain a higher mean arterial pressure and minimize the incidence of hypotension in dogs during general anesthesia [ 2 , 11 , 26 ]. Propofol-based TIVA has been investigated extensively and is used clinically in canine practice [ 1 , 2 , 3 , 5 , 26 , 28 , 29 ].…”

“…Compared with inhalational anesthetic agents such as isoflurane, propofol has been reported to maintain a higher mean arterial pressure and minimize the incidence of hypotension in dogs during general anesthesia [ 2 , 11 , 26 ]. Propofol-based TIVA has been investigated extensively and is used clinically in canine practice [ 1 , 2 , 3 , 5 , 26 , 28 , 29 ]. However, TIVA with propofol alone cannot provide analgesic effect or achieve suitable general anesthesia for surgery in humans [ 7 ].…”