Pharmacokinetic dosing of aminoglycosides aims to achieve high peak concentrations for efficacy while minimizing toxicity. The volume of distribution and half-life determine dosing frequency, with the goal of peaks above minimum inhibitory concentrations and troughs below toxic levels. Dosing is calculated using equations relating the dose, volume of distribution, elimination rate constant, and desired concentration changes over time.
Statistical softwares used in pharmacoeconomics @ RxVichuZ!! :)RxVichuZ
This summarized outline deals with SOFTWARES USED IN PHARMACOECONOMIC STUDIES, their precise details, merits & summarized relevant applications.
With respect to PHARMACOEPIDEMIOLOGY & PHARMACOECONOMICS subject.
Nomograms and tabulations in design of dosage regimens pavithra vinayak
Nomograms and tabulations in the design of dosage regimens --- NOMOGRAM IN UREMIC PATIENTS: NOMOGRAM FOR RELATIONSHIP BETWEEN CREATININE CLEARANCE AND ELIMINATION RATE CONSTANT FOR FOUR DRUGS clinical pharmacokinetics and therapeutic drug monitoring ---fifth PharmD notes
Statistical softwares used in pharmacoeconomics @ RxVichuZ!! :)RxVichuZ
This summarized outline deals with SOFTWARES USED IN PHARMACOECONOMIC STUDIES, their precise details, merits & summarized relevant applications.
With respect to PHARMACOEPIDEMIOLOGY & PHARMACOECONOMICS subject.
Nomograms and tabulations in design of dosage regimens pavithra vinayak
Nomograms and tabulations in the design of dosage regimens --- NOMOGRAM IN UREMIC PATIENTS: NOMOGRAM FOR RELATIONSHIP BETWEEN CREATININE CLEARANCE AND ELIMINATION RATE CONSTANT FOR FOUR DRUGS clinical pharmacokinetics and therapeutic drug monitoring ---fifth PharmD notes
This presentation will give the students a basic knowledge about the pharmacokinetics of durgs. It will help them clear the basics before digging deep into the topic.
GENETIC POLYMORPHISM IN DRUG METABOLISM.pptxAmeena Kadar
Genetic Polymorphism is one of the factors that affects the Drug metabolism. Cytochrome P - 450, one of the prominent group of metabolizing enzymes. In this ppt, genetic polymorphism of cytochrome p 450 is discussed.
Clinical pharmacokinetics and its application--
1)definition
2) APPLICATIONS OF CLINICAL PHARMACOKINETICS
Design of dosage regimens:
a) Nomograms and Tabulations in designing dosage regimen,
b) Conversion from intravenous to oral dosing,
c) Determination of dose and dosing intervals,
d) Drug dosing in the elderly and pediatrics and obese patients.
Pharmacokinetics of Drug Interaction:
a) Pharmacokinetic drug interactions
b) Inhibition and Induction of Drug metabolism
c) Inhibition of Biliary Excretion.
Therapeutic Drug monitoring:
a) Introduction
b) Individualization of drug dosage regimen (Variability – Genetic, Age and Weight, disease, Interacting drugs).
c) Indications for TDM. Protocol for TDM.
d) Pharmacokinetic/Pharmacodynamic Correlation in drug therapy.
e) TDM of drugs used in the following disease conditions: cardiovascular disease, Seizure disorders, Psychiatric conditions, and Organ transplantations
Dosage adjustment in Renal and Hepatic Disease.
a. Renal impairment
b. Pharmacokinetic considerations
c. General approach for dosage adjustment in renal disease.
d. Measurement of Glomerular Filtration rate and creatinine clearance.
e. Dosage adjustment for uremic patients.
f. Extracorporeal removal of drugs.
g. Effect of Hepatic disease on pharmacokinetics.
Population Pharmacokinetics.
a) Introduction to Bayesian Theory.
b) Adaptive method or Dosing with feedback.
c) Analysis of Population pharmacokinetic Data
Historically, drugs were discovered by identifying the active ingredient from traditional remedies or by serendipitous discovery, as with penicillin. More recently, chemical libraries of synthetic small molecules, natural products or extracts were screened in intact cells or whole organisms to identify substances that had a desirable therapeutic effect in a process known as classical pharmacology. After sequencing of the human genome allowed rapid cloning and synthesis of large quantities of purified proteins, it has become common practice to use high throughput screening of large compounds libraries against isolated biological targets which are hypothesized to be disease-modifying in a process known as reverse pharmacology. Hits from these screens are then tested in cells and then in animals for efficacy
conversion from INTRAVENOUS TO ORAL DOSING----- design of dosage regimenpavithra vinayak
conversion from INTRAVENOUS TO ORAL DOSING----- TYPES OF IV TO PO THERAPY CONVERSIONS: MEDICATIONS INCLUDED IN AN IV TO PO CONVERSION PROGRAM: SELECTION OF PATIENTS FOR IV TO PO THERAPY CONVERSION: design of dosage regimen--clinical pharmacokinetics and therapeutic drug monitoring-- fifth pharm D notes
Defined daily dose-DDD
B Pharm, Pharm D and medicine syllabus
Useful for examination and regulatory function information
Useful for Pharmacovigilance interview and medical coding also.
Good Luck and all the best!!!
This presentation will give the students a basic knowledge about the pharmacokinetics of durgs. It will help them clear the basics before digging deep into the topic.
GENETIC POLYMORPHISM IN DRUG METABOLISM.pptxAmeena Kadar
Genetic Polymorphism is one of the factors that affects the Drug metabolism. Cytochrome P - 450, one of the prominent group of metabolizing enzymes. In this ppt, genetic polymorphism of cytochrome p 450 is discussed.
Clinical pharmacokinetics and its application--
1)definition
2) APPLICATIONS OF CLINICAL PHARMACOKINETICS
Design of dosage regimens:
a) Nomograms and Tabulations in designing dosage regimen,
b) Conversion from intravenous to oral dosing,
c) Determination of dose and dosing intervals,
d) Drug dosing in the elderly and pediatrics and obese patients.
Pharmacokinetics of Drug Interaction:
a) Pharmacokinetic drug interactions
b) Inhibition and Induction of Drug metabolism
c) Inhibition of Biliary Excretion.
Therapeutic Drug monitoring:
a) Introduction
b) Individualization of drug dosage regimen (Variability – Genetic, Age and Weight, disease, Interacting drugs).
c) Indications for TDM. Protocol for TDM.
d) Pharmacokinetic/Pharmacodynamic Correlation in drug therapy.
e) TDM of drugs used in the following disease conditions: cardiovascular disease, Seizure disorders, Psychiatric conditions, and Organ transplantations
Dosage adjustment in Renal and Hepatic Disease.
a. Renal impairment
b. Pharmacokinetic considerations
c. General approach for dosage adjustment in renal disease.
d. Measurement of Glomerular Filtration rate and creatinine clearance.
e. Dosage adjustment for uremic patients.
f. Extracorporeal removal of drugs.
g. Effect of Hepatic disease on pharmacokinetics.
Population Pharmacokinetics.
a) Introduction to Bayesian Theory.
b) Adaptive method or Dosing with feedback.
c) Analysis of Population pharmacokinetic Data
Historically, drugs were discovered by identifying the active ingredient from traditional remedies or by serendipitous discovery, as with penicillin. More recently, chemical libraries of synthetic small molecules, natural products or extracts were screened in intact cells or whole organisms to identify substances that had a desirable therapeutic effect in a process known as classical pharmacology. After sequencing of the human genome allowed rapid cloning and synthesis of large quantities of purified proteins, it has become common practice to use high throughput screening of large compounds libraries against isolated biological targets which are hypothesized to be disease-modifying in a process known as reverse pharmacology. Hits from these screens are then tested in cells and then in animals for efficacy
conversion from INTRAVENOUS TO ORAL DOSING----- design of dosage regimenpavithra vinayak
conversion from INTRAVENOUS TO ORAL DOSING----- TYPES OF IV TO PO THERAPY CONVERSIONS: MEDICATIONS INCLUDED IN AN IV TO PO CONVERSION PROGRAM: SELECTION OF PATIENTS FOR IV TO PO THERAPY CONVERSION: design of dosage regimen--clinical pharmacokinetics and therapeutic drug monitoring-- fifth pharm D notes
Defined daily dose-DDD
B Pharm, Pharm D and medicine syllabus
Useful for examination and regulatory function information
Useful for Pharmacovigilance interview and medical coding also.
Good Luck and all the best!!!
Pharmacokinetic concepts and principles in humans in order to design individualized dosage regimens which optimize the therapeutic response of a medication while minimizing the chance of an adverse drug reaction.
Antibiotic dose modification is crucial on patients with CRRT with sepsis and MOF. This talk highlights the importance of achieving plasma therapeutic drug concentration in ICU patients to enhance their chances of survival while on CRRT
Managment of Resistant Gram Negative InfectionsYazan Kherallah
This presentation discuuses the treatment options among: β-lactam/ β-lactamase inhibitor eg cefoperazone/sulbactam
Fluoroquinolone
Cefepime
Tigecycline
Carbapenem
Colistin
For the management of Resistant Gram Negative Infections
In this presentation we discuss social media definition, social media landscape, social media facts and statistics in 2013, professional use of social media, use of Social Media in research and strategies for putting social media in practice, and lastly challenges, guidelines & regulations. Prepared by Yazan Kherallah
Microbiological Basics and Antimicrobial Susceptibility TastingsYazan Kherallah
Presents the basic concepts of microbiology including colony morphology, blood agar and hemolysis, Cellular Morphology and Arrangement, staining, Antibiotic Killing Curves, and Antimicrobial Susceptibility Testing. Prepared by Yazan Kherallah.
Mechanism of action of major antibiotic classes including betal lactam agents, aminoglycosides, macrolides, tetracyclines, quinolons, vancomycin, oxazolidionons. Detailed review and illustrations
This lecture discusses principles of selecting antifungal agents in the intensive care unit in the treatment of suspected candidasis or confirmed fungemia.
In this presentation we discuss social media definition, social media landscape, social media facts and statistics in 2013, professional use of social media, use of Social Media in research and strategies for putting social media in practice, and lastly challenges, guidelines & regulations. Prepared by Yazan Kherallah
Antifungal Strategies in the Intensive Care UnitsYazan Kherallah
Discuss the different anti-fungal treatment strategies for suspected systemic candidiasis in the intensive care units: prophylaxis, preemptive, empiric and definitive.
This presentation focuses on appropriate selection of antibiotics in the ICU and discusses different strategies to optimize this selection with the aim to decrease resistance and improve appropriateness.
This presentation discusses the latest evidence for blood transfusion triggers in the intensive care unit of various clinical condition including severe sepsis, GI bleed, post surgical cases, and post cardiac surgery among other cnditions
An Updated presentation of the management of severe sepsis including best evidence for fluid resuscitation, vasopressors, blood pressure target, steroid replacement, blood transfusion and other moralities.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
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- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
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The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
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Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
2. Objectives
• Understand the rationale supporting the
pharmacokinetic dosing model
• Discuss and interpret pharmacokinetic
concepts that affect aminoglycoside dosing
– Volume of distribution
– Half-life / Elimination rate
• Utilize pharmacokinetics to properly dose
aminoglycosides
3. Pharmacokinetics (PK) vs.
Pharmacodynamics (PD)
• Definitions:
– PK: The process by which a drug is absorbed,
distributed, metabolized, and eliminated by the
body
– PD: The study of the action or effects of drugs on
living organisms
• In other terms:
– PK: what the body does to the drug
– PD: how the drug acts on the body
• One must understand the PD of a drug before
using PK to design a dosing regimen
5. Literature Support
• Multiple studies have demonstrated the
relationship of PK/PD for aminoglycosides
– Plasma levels and outcome
• Sepsis
• Pneumonia
– Peak:MIC ratio
– Altered Vd in the critically ill
• Goals
– Provide efficacious dosing
– Minimize drug toxicity
6. Association of Serum Levels and
Outcome
• Initial doses of 2 mg/kg gentamicin or
tobramycin (8 mg/kg amikacin) given to septic
patients (n=89)
– In combination with a β-lactam
• Therapeutic initial peaks
– Gent/tobra: > 5 mcg/ml
– Amikacin: > 20 mcg/ml
• Outcome = Mortality
– Therapeutic: 2.4% (1/41)
– Subtherapeutic: 20.9% (9/43)
J Infect Dis 1984;149(3):443-8
7. Association of Serum Levels and
Outcome
• Initial doses of 2 mg/kg gentamicin or tobramycin (8
mg/kg amikacin) given to pneumonia patients (n=37)
– In combination with a β-lactam
• Therapeutic initial peaks
– Gent/tobra: > 7 mcg/ml
– Amikacin: > 28 mcg/ml
• Outcome = “Successful Outcomes”
– Therapeutic: 78% (14/18)
– Subtherapeutic: 32% (6/19)
• Multivariate analysis
– Most important predictor of positive outcome
Am J Med 1984;77:657-662
8. Importance of Peak:MIC Ratio
• Initial doses of 2 mg/kg gentamicin or
tobramycin (8 mg/kg amikacin) given to sepsis
patients (n=236)
– In combination with a β-lactam
• 188/236 patients had favorable response to
antibiotics
• Most important factors for favorable response
(univariate analysis)
– Favorable underlying prognosis (p=0.0001; R=0.36)
– Maximal peak:MIC ratio > 10 (p=0.0005; R=0.21)
J Infect Dis 1987;155(1):93-9
9. Importance of Peak:MIC Ratio
Table of Peak:MIC ratios and relative odds of
favorable response
Max Peak:MIC
(mcg/ml)
Relative Odds 95% Confidence
Interval
< 2 1.00
2-<4 1.63 0.84-3.16
4-<6 1.83 1.09-3.03
6-<8 4.35 2.53-7.46
8-<10 6.49 3.56-11.82
>10 8.41 4.62-15.33
J Infect Dis 1987;155(1):93-9
10. Achieving Acceptable Peak:MIC
Ratios in the Critically Ill
• 53 SICU patients in septic shock given
gent/tobra
– Loading dose: 3 mg/kg of IBW or adjusted BW
• 50% of the difference between IBW and actual weight
• Mean initial peak = 8.1 + 0.3 mcg/ml
– Only achieved in 50% of patients
– Mean Vd = 0.29 L/kg (0.2-0.54 L/kg)
– 34% had increased Vd
• 4mg/kg dose is back-calculated
Surgery 1998;124:73-78
15. Aminoglycoside Dosing Regimen
• Usually based on actual body weight (ABW)
• Administer:
– Gent/Tobra 4 mg/kg IV x 1
– Amikacin 16 mg/kg IV x 1
• Draw 1 hour post-infusion peak and 8-12
hour random level
• Goal peaks
– Gent/Tobra = 8-10 mcg/ml
– Amikacin = 32-40 mcg/ml
16. Pharmacokinetic Equations
• Calculate Vd
– Needed for dose adjustment
– Vd = Dose given (mg) / peak (mg/L)
• Calculate ke and t1/2
– Determine frequency of drug administration
– ke = ln (peak/random) / Δt
– t1/2 = 0.693 / ke
• In how many half lives should you re-dose?
• Predict when appropriate to re-dose
– Ct = Co e (-ke x t)
17. Case: Volume of Distribution
• JK is a 75 yo male is POD 2 ex lap for SBO
and is now septic and hypotensive
• Discussion on rounds leads to the initiation of
antibiotics
– Pip/Tazo 3.375 g IV q6h
– Vancomycin 1 g IV q12h
– Gentamicin….
18. Case: Volume of Distribution
• Patients weight:
– Actual = 85 kg
– IBW = 76 kg
• What dose do you want to give of
gentamicin?
• When do you draw levels to calculate
regimen?
Gentamicin 340 mg IV x 1 over 30 minutes
Draw levels 1 hour and 8 hours post infusion
19. Case: Volume of Distribution
• Gentamicin is ordered and given at 0900
(after speedy pharmacy processing!)
• Levels to follow
– 1030: 11.2 mcg/mL
– 1800: 6.7 mcg/mL
• Calculate Vd
• Normal Vd is:
Vd = 340 mg / 11.2 mg/L = 30.3 L
= 0.36 L/kg
0.25-0.3 L/kg
20. Case: Elimination and Half-life
• JK’s levels
– 1030: 11.2 mcg/mL
– 1800: 6.7 mcg/mL
• Calculate ke
• Calculate T1/2
ke = ln (1 hr level/8 hr level) / change in time
ln (11.2 / 6.7 ) / 7.5
0.0685 hrs-1
t1/2 = 0.693 / ke
≈ 10 hrs
21. Case: When to re-dose?
• If clearance remains stable, it can be
assumed that the next dose could be given in
4 half lives
• Ct = Co e (-ke x t) can be used to predict when a
level will be < 2 mcg/ml
– Re-arrange equation to
– This will give you how many hours until serum
concentration is < 2 mcg/ml
– JK:
t = [ln Co – 0.693] / ke
≈ 18 hours must elapse until level is
< 2 mcg/ml
22. Case: The Next Dose
• Utilizing the patient-specific Vd for JK, what is the
next dose of gentamicin?
• Things to consider…
– Changing Vd
• Active diuresis?
• Third spacing?
– Changing ke
• CVVHD
– Clotting? Increasing flow rates?
• Declining/improving renal function?
Dose = Vd x desired increase in serum level
= 30.3 L x 8 mg/L (why 8 mg/L?)
= 240 mg
23. Take Home Points
• Aminoglycosides should be administered with
the goal of achieving therapeutic peaks early
• Dose is related to Vd
– As volume increases, so does the dose (and the
reverse is true)
– Dose is independent of elimination
• Frequency of dose is related to half-life and
elimination
24. Equations to Know
• Dose is 4 mg/kg of actual or adjusted weight
• Volume of distribution:
– Vd = Dose given (mg) / peak (mg/L)
• Elimination constant (ke)
– ke = ln (peak/random) / Δt
• Half-life
– t1/2 = 0.693 / ke
• Time until level is safe for redosing:
– t = [ln Co – 0.693] / ke (for gent/tobra)
– t = [ln Co – 2.01] / ke (for amikacin)