Ketamine analgesia produces intense analgesia at sub anesthetic doses and prompt induction of anesthesia when administered IV at higher doses. Ketamine analgesia has an analgesic action at many sites both centrally and peripherally. These actions are mediated via multiple receptor subtypes, including opioid, NMDA, kainate, and GABAA receptors. Ketamine also inhibits serotonin and dopamine reuptake. […]
Ketamine is associated with psychedelic effects and dependence. Well the question here arises is that Is Ketamine addictive ? These effects are dose-related and comprised of multimodal hallucinatory experiences, a sense of slowing, paranoid ideation and enhancement of sexual, musical and sensory enjoyment. The mechanisms of these phenomena are largely due to its complex multi-receptors
One may ask what is methylene blue ? Methylene blue is a water-soluble blue thiazine dye used most commonly as a treatment for methemoglobinemia or as an indicator dye. Its utility as an indicator dye has been applied to several clinical situations including identification of aspiration or placement of nasogastric tubes in critically ill patients;
The exact site of mechanisms of action of inhalation anesthetics is not certain but possible sites are macroscopic (CNS-brain), microscopic (axons and synapses) and molecular (pre- and postsynaptic membranes). Hence, the possible mechanisms of action of inhalation anesthetics is varied: a) Multiple receptor sites b) Motor inhibition at spinal cord level c) Many neurotransmitters are
The effect of Ketamine on brain the Ketamine is traditionally considered to increase cerebral blood flow and CMRO2 however, positron emission tomography shows that subanesthetic doses of racemic ketamine increase cerebral blood flow with a minor increase in regional CBV but do not affect oxygen consumption significantly. The most profound changes in regional CBF with Ketamine on
For premedication, the recommended midazolam dosage is 0.07 to 0.08 mg/kg IM (usual dose is about 5 mg IM for an average adult) administered 30 to 60 minutes preoperatively. Lower doses should be used in elderly or debilitated patients. In a study of patients 60 years or older who did not receive concomitant narcotics, 2
Nitroprusside Cyanide Toxicity is due to the cyanide groups released from metabolism of the nitroprusside molecule. After gaining an electron from the iron moiety of hemoglobin, the sodium nitroprusside produces an unstable radical and methemoglobin. Hypertension is commonly seen in the perioperative setting as well as the intensive care unit (ICU). There are many agents
Some barbiturates effects are explained here. The thiopental sodium causes profound fall in cerebral blood flow (35 to 40%) and thus ICP. Thiopentone also causes profound decrease in CMRO2. Thiopentone increases Cerebral perfusion pressure (CPP). The barbiturates effects increased the amplitudes of subcortical and early cortical components of somatosensory evoked potentials. Even full suppression of
The binding site is called the ‘receptor’ and the mechanism as opioid receptor mechanism . Any pharmacological activity requires an agent, a target organ and a specific binding site in that organ. The receptor due to its affinity to the drug and opioid receptor mechanism , permits attachment of the drug to itself, which then
The chronic pain syndrome pathophysiology is disturbance in the process of acute nociception. The processes of transduction, transmission, modulation and perception have somehow got disturbed. The pain stimuli which were supposed to be sent forward before closing of gate, get more and more intensely forwarded rather than getting modulated. In addition, due to sustained partial
