Sedatives are described as a variety of therapeutic substances that decrease cerebral function and can produce a continuum of cognitive states, from minimal sedation to general anaesthesia. Analgesics have pain relief activity and work on the physiological mechanisms of pain. There are many classes of analgesics, but opioid analgesics, acting through opioid receptors, remain the mainstay of therapy for alleviating pain in critically ill patients. In 2014, Yan and Jiang109 reviewed preclinical and clinical data, suggesting the neurotoxic and neuroprotective effects of ketamine may depend on dose, exposure frequency, and the presence or absence of noxious stimuli. This was highlighted by Brown and colleagues110 in 2015, who found that lower doses (5 mg kg−1) prevented apoptosis, whereas higher doses (20 mg kg−1) induced apoptosis.
Intubation, Hypotension and Shock
Clinically significant vital sign change was defined as an increase or decrease of greater than or equal to 20% from baseline. Although these reactions can be quickly treated with a benzodiazepine, hypertension and tachycardia are often seen during these episodes, along with hallucinations and panic. This can cause an increase in oxygen consumption, as well, that could attribute to observed cardiac effects, specifically in patients with underlying cardiac disease 4-6.

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- Other agents, including propofol, opioid analgesics, and anti-emetics, specifically ondansetron, were administered during the procedural sedations at the discretion of the treating provider (Figure 1).
- This was highlighted by La Via and colleagues79 in 2022, who concluded that the limited number of studies available and large heterogeneity prevented ketamine use in severe asthma from being recommended currently and that large, well-designed studies are required.
- This review highlights the potential of R-ketamine to provide more potent and longer-lasting antidepressant effects compared with S-ketamine.
Certain cardiovascular conditions are contraindications for ketamine therapy because they impair the heart’s ability to tolerate the increased workload. Patients with uncontrolled severe hypertension are at higher risk, as the drug’s effects can elevate blood pressure to dangerous levels. Similarly, individuals who have recently had a heart attack or suffer from unstable angina have compromised coronary arteries that may not supply the necessary oxygen to meet the heightened demand. Although, there is currently a scientific debate on the validity and strength of the data in favor of this drug,22 patient screening and careful monitoring of BP and cardiovascular functioning are important during the time patients are receiving treatment with esketamine. Patients with cardiovascular diseases should not be treated with ketamine if the risk outweighs the benefits in this population, but regardless of psychotropic medication taken it seems safe and well tolerated. Research indicates that the development of post-cardiac arrest brain injury (PCABI) is a critical determinant of mortality and neurological outcomes in patients who have experienced cardiac arrest.
Associated Data
Interest in using ketamine to treat numerous psychiatric conditions has gained traction over recent years. These include major depressive disorder (MDD), posttraumatic stress disorder (PTSD), and substance misuse. Ketamine in this application has the additional benefits of few to no life-threatening adverse effects of accidental intravenous or intrathecal administration. All authors have met authorship requirements, and the final manuscript was approved by all authors. This manuscript has not been published elsewhere and is not under consideration by another journal.
While the use of paralytics for airway management and maintenance of a sedated patient falls within the skillset of an advanced provider, it is good for the medic to have an understanding of the science behind it. Ketamine was first synthesized in 1962 by Calvin Stevens at Parke-Davis Co (now Pfizer) as an alternative anesthetic to phencyclidine. It was first used in humans in 1965 by Corssen and Domino and was introduced into clinical practice by 1970. Ketamine is frequently described as a “unique drug” because it shows hypnotic (sleep-producing), analgesic (pain-relieving) and amnesic (short-term memory loss) effects; no other drug used in clinical practice produces these three important effects at the same time. It is very important that your doctor check your progress very closely while you are receiving this medicine to see if it is working properly and to allow for a change in the dose. Your doctor will monitor your blood, heart function, blood pressure, and breathing after receiving this medicine.
- If studied in isolation, ketamine has a direct mild depressant effect on heart muscle tissue.
- Ketamine has bronchodilating effects, and protective airway reflexes are preserved to some extent.
- We observed that after chronic treatment with ketamine, PARP-1 expression was significantly elevated, suggesting its role in ketamine-induced apoptosis and fibrosis.
- Before treatment begins, a thorough screening process is conducted to identify any pre-existing heart conditions that could elevate risk.
- For example, Saito and colleagues157 demonstrated that lung carcinoma cell lines have greater sensitivity to ketamine than neuroglioma cells; however, both cell types exhibited dose-dependent reductions in cell proliferation and migration and an increase in apoptosis.
Adverse effects
We report a case of an 8-year-old girl, previously diagnosed with tetralogy of Fallot who presented for operative correction of the congenital anomaly. On the second postoperative day, and upon removal of a chest drain with the use of ketamine for sedation, the patient suffered cardiopulmonary arrest. After repeated cycles of resuscitation, the patient returned to spontaneous circulation. The extra work done by the heart eventually starts to damage the cells and tissues that make up the heart muscle. As the heart’s functional capacity weakens, the likelihood of cardiac arrest increases.
The use of ketamine as a neuroprotective agent following cardiac arrest: A scoping review of current literature
Limitations of this article include the lack of systematic review procedures to appraise available evidence and meta‐analyze research results. This limitation could not be addressed due to the lack of clinical trials evaluating the topic of this literature review, in addition to the large heterogeneity of types of studies and reports retrieved by the results of the literature search. As such, the body of knowledge summarized in this article is intended to serve as a scoping review only and not a formal analysis of available evidence. PCABI results in apoptosis of neurons, particularly in the highly metabolically active hippocampal and neocortical areas.
Understanding this relationship is important for its safe administration in clinical settings. A study in Anesthesia and Analgesia journal in 1980 proposed that in severely ill patients, preoperative stress may alter the usual physiologic responses to ketamine administration and adverse effects may predominate. It was found that a single dose of ketamine produced decreases in cardiac and pulmonary performance and in peripheral oxygen transport in this group of patients 6.
In 2000, Berman and colleagues80 published the first placebo-controlled trial of the antidepressant properties of ketamine in MDD, highlighting NMDA receptor modulation as a potential treatment mechanism. Prospectively, a convenience sample of patients older than 50 years receiving ketamine for procedural sedation in the ED was used. Recruitment occurred during hours when the three-person research team members were working clinically in the ED.
In 2024, Shafique and colleagues94 published a comprehensive review of the literature comparing S-ketamine and R-ketamine in depression. This review highlights the potential of R-ketamine to provide more potent and longer-lasting antidepressant effects compared with S-ketamine. Although there are promising animal and preclinical studies, the authors caution that overall data on R-ketamine in humans are limited. Ketamine has gained popularity as an anaesthetic agent owing to its favourable cardiovascular effects in haemodynamically compromised patients.
Pain
An analogous situation occurred for diastolic RR after 1 infusion does ketamine cause cardiac arrest – a higher increase in diastolic RR is observed among people with HA compared to those not suffering from HA. The analyses compared measurements in patients with and without essential hypertension, patients who were treated for TRD-MDD and TRD-BP, patients treated with different classes of psychopharmacological agents are presented in Table 5. She was started on intravenous furosemide drip as well as guideline directed medical therapy (GDMT), which she tolerated well and had adequate urinary output. Repeated echocardiography 2 weeks later revealed an improved EF of 25% along with a decrease in tricuspid regurgitation grade from severe to moderate. Indeed, a direct negative cardiac inotropic effect is usually overshadowed by central sympathetic stimulation. The study took place at an academic medical center with a level-one trauma designation that serves as a regional referral center for orthopedic injuries and other specialty care.
We sought to discover if patients greater than 50 years of age who received ketamine during routine procedural sedation would have changes suggestive of cardiovascular ischemia seen on an ECG performed during the sedation. Strict monitoring protocols are standard practice during ketamine administration. Before treatment begins, a thorough screening process is conducted to identify any pre-existing heart conditions that could elevate risk. This assessment helps ensure that only suitable candidates receive the medication. In effect, ketamine’s mechanism of action within the brain can cause real problems when taken in large amounts, so cardiac arrest is definitely possible.
This means a ketamine abuse problem can easily spin out of control when using this drug on a repeated basis. Under these conditions, the risk of going into cardiac arrest increases exponentially. Ketamine is the medication of choice for traumatically injured patients with moderate to severe pain and whose vital signs are potentially unstable. Ketamine is also a medication of choice for patients with excited delirium, patients requiring disassociation, for rapid sequence airway management, for sedation and the maintenance of sedation. Ketamine also has a place in a number of other pathologies, including its newest area of research, use in depression. Researchers have also considered the neuroprotective properties of ketamine after cardiac arrest.