What is plasma therapy for Covid-19


 

As the world is suffering from pandemic by Covid-19, the effort to find an effective treatment is on a war footing.  Few drugs like HCQS, Remdesvir, and Tocilizumab are being tested, vaccines are being developed. A vaccine may be a mainstay in the future , but till that time, how to control mortality.  Convalescent plasma therapy has been found to be useful in China.

Convalescent plasma is an antibody-rich plasma product prepared from the blood donated by the patients, who have recovered from Covid-19 infection recently. These patients are tested twice negative and ELISA can also be done to check for antibodies. The antibodies are proteins with the capability to fight infection in the body and are important component of the immune system

  Antibody rich plasma can be taken after two weeks after  the patient has recovered. The plasma of such patients has the potential to treat or lessen the severity of Covid -19. Plasma taken from one patient may help three to four patients. A donor can again donate after one week. The subsets of patients who may benefit are sick patients in ICU, on the ventilator and are having a risk of death.

The plasma therapy was used for diphtheria and tetanus  about 120 years ago and  used for viral infections like EBOLA

ICMR has permitted  for clinical  trials  of plasma therapy for Covid -19

FDA  has also permitted to pool the donor volunteers.

Reclaim of Lost Territory by Mighty Nature #COVID-19


 

         For thousands of years, humans have achieved tremendous progress and evolution, which was reflected in advancement and modern science. The evolution was used to acquire natural wealth and the environment to the materialistic advantage of mankind. From butchering animals to control sea waters and skies, humans tried to control everything around. Modern medicine was discovered to attack the germs, bacteria, and viruses in a pursuit to prolong life and interfered severely in natural processes of nature without knowing the bigger picture. A sense of holding masterly gained by possessing superior intelligence prevailed in the modern world.  Except for humans, everything living or non-living was being considered as a captive resource to be exploited and consumed. Animals and birds were farmed, tormented and mercilessly killed in uncountable numbers.

        In a few weeks of invasion by COVID-19, the world looked changed. Greener plants, no air pollution, transparent waters, and clear sky looked, no traffic on roads, as if nature claiming back the lost territory without being even seen.

         All living and non-living elements form an ecosystem. Birds, animals, plants, sea life, the environment on earth, non-visible germs and bacteria form an ecosystem and form a balance. How we have affected this balance, that is still unknown.  Germs have been there before humans and are armed with strange powers to mutate and attack humans if balance is disrupted. The real barriers between deadly nano predators and human beings are still undiscovered. When we pollute and destroy the hills and jungles, deserts and oceans, icy glaciers and lush rain forests, use antibiotics to kill micro- and nano-life for our evolved requirements, we force the barriers to be broken.

     The rapidly recurrent coming pandemics may be warning for the behavior of the human race, and point towards a need for more sustainable evolution. The mighty nature deserves more respect to be kind to humans.

     Human beings need to prove that they are truly evolved. Considering that the current invasion by COVID -19 is not the last one that befell us, there can be many more in future, we need to check our pattern of choices to suit the nature and not vice-versa.

21 occupational risk to doctor and nurses

reel heroes vs real heroes

Myths about medical-Ventilator; Corona may help to burst


Unfortunately, celebrities and media have most of the time fuelled the myths and common allegations against the medical profession and ventilator. The myths have been propagated rather than disseminating the truth. This is no truth in such projected and perceived hearsay.

Someone who is drowning, a small boat can save his life, till sea storm settles or the victim reaches a safe land. The boat will not settle the sea storm, but enough to save a person from catastrophe. In reality, a ventilator is the invention, which should be worshiped. But contrarily, due to wrong projections and misguided perceptions, it has been hated despite saving lives.

Although doctors and ventilators are in a similar situation, projected in the wrong way, hated in spite of doing good work and saving lives. They are hated and despised, despite the only ones of help in life and death situations. The following are a few myths and facts about the ventilator.

  1. Myth: Once on a ventilator, patients do not survive: the common myth is that once the patient is placed on a ventilator, he will not survive. The human body, when it gets severely diseased or under stress, heart and lungs need to be supported for saving the life, till ailment So, when the battle for saving a life is ongoing, almost all the patients will have to be placed on the ventilator. It is a last-ditch attempt made to save the patient’s life. However when the patients do not survive people feel that it’s the ventilator that has caused death, rather than a rational thought about the severe disease as a cause.

In reality, it is the severity of disease and the possibility of death, when the ventilator is required. It is necessary to support life.

  1. Myth: Ventilator is a modality for the mere prolongation of life: every disease has a spectrum. Every disease can progress from a reversible to an irreversible state. As an effort is ongoing while waiting to reverse the process, the patient will need ventilator to sustain life. Unless the disease reaches a stage of irreversibility, the ventilator is indispensable for an absolute need to maintain life. Since in serious condition, it is an uncertain prognosis. In retrospect, combined with the application of average wisdom, the time of uncertainty and institution of the ventilator can be interpreted as a mistake. As the whole exercise is labeled as futile and expensive by relatives. it’s a grey area and the negative thoughts are fuelled because of retrospective wisdom in hindsight. The real prognosis cannot be predicted in real-time.

In reality, Ventilator is a machine which just supports respiration and not responsible for heart beating. Therefore it buys time for healing and treatment of primary disease.

  1. Myth: Ventilator will cause death:

one can understand this simple logic on the basis that patients are placed on dialysis when kidneys fail. Patients are placed in the cast when bones are fractured for a fixed predefined period of time. Similarly, patient is placed on a ventilator when the lungs fail. The ventilator is used till the time lungs recover and become fully functional.

In reality; Risk is because of disease, which needs ventilator and not vice versa. Ventilator is a friendly machine which helps people who have failed lungs.

  1. Myth : Doctors and hospitals keep dead patients on ventilator for financial gains

Fact: placing patient on ventilator is a very critical decision, taken in best interest of patient to buy time, to so as to treat the disease. A patient needing on ventilator is actually so sick, that not instituting ventilator will risk the patient’s life. Knowing all these facts, doctors take a decision to keep the patients on a ventilator.

Once the patient is on ventilator, it is a stress for the doctor to take the patient off the ventilator. As such ventilator is a SANCTUM SANCTORUM lifesaving machine, to be used only in life and death situations.

  1. Myth : Its a miracle if the patient placed on ventilator survives.

Given the fact that placing the patient on ventilator on scientific facts. There are clear indications for putting the patient on ventilator. A much larger patients put on ventilator are actually saved and go home.

Fact: Everyday thousands of patients are placed on ventilator and sent home to lead a normal life: Any patient who is given general anesthesia is placed on ventilator in the operation theater and then taken off the ventilator at the end of the surgery. In these cases patients are placed on ventilator so as patient can be put to deep sleep (called anesthesia) during which surgery on desired part can be carried out. Soon after the surgery patient are taken off the ventilator and soon thereafter discharged for home after few days of healing.

  1. Myth :Doctors place patients on ventilator at their own will:

Fact: there are scientific parameters which decide when the patient should be placed on the ventilator and when the patient should be taken off the ventilator. So the decision to place the patient is scientific and based on objective parameters.

Contrary to this popular myth, it is a compulsion for the doctor to put patient on ventilator to prevent death in serious situations. Doctors are usually thinking several steps ahead of lay person about medical science.

  1. Myth :All patients placed on ventilator are unconscious:

Fact: this is not necessary. Usually patients are sedated for their comfort. they can be made to walk, write and even perform small tasks when on ventilator, depending upon their lung condition.

Patients are also put on ventilator in case of airway failure when unable to protect their airway for various reasons. Another reason why patients are placed on ventilator is inability of the patients to protect his or her airway. Conscious and alert patients can swallow normally formed mouth secretions. When patients consciousness level is dulled the ability of the patient to protect his airway is lost or compromised. This causes secretions from mouth to enter into the lungs through the airway i.e. trachea causing infections in the lungs. The only way to prevent this and protect the patient’s lungs is to place a tube in his airway and then place them on the ventilator.

  1. Myth: Patients can be kept alive by placing on the ventilator:

General masses have a feeling that patient can be kept alive by keeping them on the ventilator. Even a dead person can be kept alive by placing on the ventilator, which is not true.

In reality: It is machine used only for breathing and not heart and brain.

  1. Myth : Ventilating the dead patients:

this is a common allegation on medical profession. This is no truth in this projected and perceived hearsay.

Facts: Assumptions are based on thoughts of lay persons. Patients on ventilator, may look like dead, because of the disease, sedation and paralyzed by drugs. But their heart and brain are working, so they cannot be declared dead.

If there is some incident, it needs to be proved by medical personnel. In reality, it can be a very rare and remote exception. These untrue projection are creating lots of mistrust about life saving machine.

The problem is about correct projection and majority of people without knowledge of medical science do not even know the large number of lives been saved by the ventilators.

In nutshell: serious conditions and life threatening situations need higher technical interventions, to save a life. If correct projections are made, ventilators are lifesaving machines.

About ventilator

History of ventilator

History of Major Pandemics


Disease and illnesses have always been  catastrophe to  humanity since ancient times. The magnitude of the illnesses and death rates have shown a  marked shift. The more civilized humans became – with larger cities, more exotic trade routes, and increased contact with different populations of people, animals, and ecosystems – the more likely pandemics would occur.

Despite the persistence of disease and pandemics throughout,   one trend that has emerged over time is the gradual reduction in the death rate. As the germ theory is discovered and there is a better understanding of the causative agents has led to better control. Healthcare improvements and control of infections have been powerful tools in mitigating their impact.

In many ancient societies, people believed that spirits and gods inflicted disease and destruction upon those that deserved their wrath. This unscientific perception often led to disastrous responses that resulted in the deaths of thousands.

Brief timeline for the major known pandemics :

165  AD  –  Antonine plague-  thought to be small pox or measles  and caused

around   5 million deaths.

735 AD –     Variola major virus–  Japanese smallpox  –     around 1 million deaths

541  AD-     Plague of Justinian – Yersinia pestis/ rat, fleas –   30- 50 million deaths

1347 AD-    Black death (Plague) –- Yersinia pestis/ rat fleas –   200 million  deaths

1520 AD-   Smallpox —                  Variola major virus—                  56 million deaths

1665 AD  Great plague of London–- Yersinia pestis/ rat fleas –     One lac deaths

1629 AD-         Italian plague          Yersinia pestis/ rat fleas –     death 30- 50 million

1817  AD– Cholera pandemic (6) – vibrio cholera: over 100 years-death one million

1850 AD – Third plague     –         Yersinia pestis/ rat fleas –              death –12  million

1880 AD-  Yellow fever –           Viral /     mosquitoes                    death 1 lac to 1.5 lac

1889  AD-        Russian flu-                   H2 N2 (bird)                           deaths    10 million

1918 AD–      Spanish flu  –                 H1 N1 (Pigs)                          deaths 30-50 million

1958 AD  –         -Asian Flu                                  H2 N2                                        1 million

1968 AD  –     Hong Kong flu                        H3 N2                                              1 million

1981 AD- continued -HIV/AIDS               viral/  chimpanzees                     30 -40 million

2002 AD-            SARS–                         corona virus  Civets / Bats-                     770

2009 AD              Swine Flu                        H1N1 – (pigs)                                     200,000

2014 AD –           EBOLA                                 Ebola virus  –                                       11000

2015 AD-            MERS                          Corona virus/ bats, Camel         death count 850

2019 AD           -COVID -19                         Corona virus                            -still continued

 

Antibiotic for resistant super bugs discovered by machine learning (AI) for first time


 

An important breakthrough   towards  discovering new antibiotics, that has potential to change  the ways, new molecules are discovered,  Team at MIT says HALICIN  kills some of the world’s most dangerous strains. Discovery  has been possible using artificial intelligence.  It also signifies the role of artificial intelligence in medicine, in future.

Antibiotic resistance arises when bacteria mutate and evolve to sidestep the mechanisms that antimicrobial drugs use to kill them. Without new antibiotics to tackle resistance, 10 million lives around the world could be at risk each year from infections by 2050.

To find new antibiotics, the researchers first trained a “deep learning” algorithm to identify the sorts of molecules that kill bacteria. To do this, they fed the program information on the atomic and molecular features of nearly 2,500 drugs and natural compounds, and how well or not the substance blocked the growth of the bug E coli.

A powerful antibiotic that kills some of the most dangerous drug-resistant bacteria in the world has been discovered using artificial intelligence.

The drug works in a different way to existing antibacterials and is the first of its kind to be found by setting AI loose on vast digital libraries of pharmaceutical compounds.

Tests showed that the drug wiped out a range of antibiotic-resistant strains of bacteria, including Acinetobacter baumannii and Enterobacteriaceae, two of the three high-priority pathogens that the World Health Organization ranks as “critical” for new antibiotics to target.

“In terms of antibiotic discovery, this is absolutely a first,” said Regina Barzilay, a senior researcher on the project and specialist in machine learning at Massachusetts Institute of Technology (MIT).

“I think this is one of the more powerful antibiotics that has been discovered to date,” added James Collins, a bioengineer on the team at MIT. “It has remarkable activity against a broad range of antibiotic-resistant pathogens.”

Once the algorithm had learned what molecular features made for good antibiotics, the scientists set it working on a library of more than 6,000 compounds under investigation for treating various human diseases. Rather than looking for any potential antimicrobials, the algorithm focused on compounds that looked effective but unlike existing antibiotics. This boosted

the chances that the drugs would work in radical new ways that bugs had yet to develop resistance to.

Jonathan Stokes, the first author of the study, said it took a matter of hours for the algorithm to assess the compounds and come up with some promising antibiotics. One, which the researchers named “halicin” after Hal, the astronaut-bothering AI in the film 2001: A Space Odyssey, looked particularly potent.

Writing in the journal Cell, the researchers describe how they treated numerous drug-resistant infections with halicin, a compound that was originally developed to treat diabetes, but which fell by the wayside before it reached the clinic.

Tests on bacteria collected from patients showed that halicin killed Mycobacterium tuberculosis, the bug that causes TB, and strains of

Enterobacteriaceae that are resistant to carbapenems, a group of antibiotics that are considered the last resort for such infections. Halicin also cleared C difficile and multidrug-resistant Acinetobacter baumannii infections in mice.

To hunt for more new drugs, the team next turned to a massive digital database of about 1.5bn compounds. They set the algorithm working on 107m of these. Three days later, the program returned a shortlist of 23 potential antibiotics, of which two appear to be particularly potent. The scientists now intend to search more of the database.

Stokes said it would have been impossible to screen all 107m compounds by the conventional route of obtaining or making the substances and then testing them in the lab. “Being able to perform these experiments in the computer dramatically reduces the time and cost to look at these compounds,” he said.

Barzilay now wants to use the algorithm to find antibiotics that are more sekills only the bugs causing an infection, and not all the healthy bacteria that live in the gut. More ambitiously, the scientists aim to use the algorithm to design potent new antibiotics from scratch.

“The work really is remarkable,” said Jacob Durrant, who works on computer-aided drug design at the University of Pittsburgh. “Their approach highlights the power of computer-aided drug discovery. It would be impossible to physically test over 100m compounds for antibiotic activity.”

“Given typical drug-development costs, in terms of both time and money, any method that can speed early-stage drug discovery has the potential to make a big impact,” he added.

Antibiotic resistance

 

 

Doctor & nurses at risk from unknown or mutated germs@ Mystery virus in China


 

First pneumonia death from mystery virus in China, world on high alert

          The  viruses, bacteria are germs  had been discovered only in last one century and many more are still not known. Patients carrying specially unknown germs are  handled by doctor and nurses, who have no clue, what they are dealing with.   Time gap in such  patients coming to the  hospital  and  the exact diagnosis of finding a dreaded disease, may be  quite dangerous to doctors and nurses. To add to the problem, In  large number of patients, exact viruses cannot be diagnosed or even suspected. In many cases of ARDS, the causative organism cannot be  isolated or identified.  It is important for  doctors and nurses  to take universal precautions from the beginning. There can be many more viruses or germs which are yet to be discovered or mutated ones that  are unknown.

21 occupational risk to doctor and nurses

H1N1, Zika,  Ebola,  SARS  are few examples,  just to imagine that they existed and handled by health workers as unknown germs, till they were discovered.

The death of a 61-year-old man  due to pneumonia from a mystery virus in the central Chinese city of Wuhan on Saturday has put the world on high alert against another new life-threatening illness. Seven of the 43 others diagnosed with the disease are in a critical condition, but no new cases have been reported since January 3.

To protect the world still smarting from the lightning spread of devastating viral diseases such as H1N1, Zika and Ebola, the World Health Organisation (WHO) issued this year’s first  international travel and trade alert on  on January 10 that advised all international travellers to report symptoms of fever with breathlessness and difficulty breathing, especially if they have travelled from China.

On January 9, China announced that the cluster of pneumonia cases reported in December in Wuhan in the Hubei Province of China was caused by a new coronavirus.

Only six viruses from the coronavirus family infect humans, which would make the new one the seventh to cause human disease. The coronavirus viruses cause diseases ranging from the common cold to very severe and life-threatening illness from Middle-East Respiratory Syndrome that caused 851 deaths since it was identified in 2012, and the Severe Acute Respiratory Syndrome (SARS), which killed 774 of the 8,098 people infected in an outbreak that started in China in 2002.

“Though currently there is no evidence of human-to-human transmission, we need to remain vigilant. WHO has shared with all Member States technical guidelines on surveillance, testing as well as infection prevention and control practices for suspected cases. WHO is in close contact with national authorities in the region and will extend all possible support to ensure core capacities are geared up for addressing potential cases that may come to countries,” said Dr Poonam Khetrapal Singh, WHO regional director, South East Asia Region.

Unknown threat

Some countries in the region, including Indonesia, Myanmar and Thailand, have started screening passengers travelling from China for pneumonia symptoms at airports. The health ministry reviewed the situation with WHO experts on Wednesday and plans to start providing travellers with risk-reduction information at airports and other ports of entry, travel agencies and conveyance operators.

“We are waiting and watching as entry screening at ports of entry like airports, seaports, train stations and border check-posts are not cost-effective. It is resource-intensive but offer little benefit,” said a health ministry official, who did not want to be named.

Though no pneumonia have been reported outside Wuhan, which has a population of 11 million, WHO said there is need for caution as the city is a major domestic and international transport hub with heavy population movement. Travel in the region is expected to significantly increase during the Chinese New Year in the last week of January, which increases the potential of infected travellers carrying to other parts of China and the world.

New viruses are formed when mutate to jump species and cause infection in humans. SARS jumped from the civet cat into humans, MERS from dromedary camel, H1N1 from pigs, and Ebola from bats, just to name a few.

The Wuhan City cases have been linked to the South China Seafood Wholesale Market, where some of the patients worked as dealers or vendors. The Huanan Seafood Wholesale Market deals with fish and other seafood, including sea mammals, along with chicken, bats, rabbits and snakes.

Signs of trouble; The clinical signs of the new lung infection are mainly fever, with a few persons reporting difficulty in breathing. Clinical signs include chest x-rays showing bilateral lung infiltrates (markings) associated with pneumonia and tuberculosis.

With no infection among health care workers treating the patients, preliminary information suggests there is no significant human-to-human transmission, but till the mode of transmission is clearly established, it’s best to take precautions to stay safe.

The WHO advises people travelling in or from affected areas (currently Wuhan) to avoid close contact with people with acute respiratory infections; wash hands frequently, especially after direct contact with ill people or their environment; and avoid close contact with live or dead animals. In case of respiratory symptoms before, during or after travel, travellers must seek medical attention and share their travel history with the doctor.

“The WHO advises against travel or trade restrictions on China based on the information currently available on this event,” said Dr Singh.

 

 

what is Mechanical ventilator? A machine critical to save life


A medical ventilator (or simply ventilator in context) is a machine designed to provide mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently.

While modern ventilators are computerized machines, patients can be ventilated with a simple, hand-operated bag valve mask.

Ventilators are chiefly used in intensive care medicine, home care, and emergency medicine (as standalone units) and in anesthesiology  (as a component of an  anesthesia machine .

Medical ventilators are sometimes colloquially called “respirators”, a term stemming from commonly used devices in the 1950s (particularly the “Bird Respirator”). However, in modern hospital and medical terminology, these machines are never referred to as respirators, and use of “respirator” in this context is now a deprecated anachronism signaling technical unfamiliarity.

Function                                  

In its simplest form, a modern positive pressure ventilator consists of a compressible air  reservoir or turbine, air and oxygen supplies, a set of valves and tubes, and a disposable or reusable “patient circuit”. The air reservoir is pneumatically compressed several times a minute to deliver room-air, or in most cases, an air/oxygen mixture to the patient. If a turbine is used, the turbine pushes air through the ventilator, with a flow valve adjusting pressure to meet patient-specific parameters. When over pressure is released, the patient will exhale passively due to the lungs’ elasticity, the exhaled air being released usually through a one-way valve within the patient circuit called the patient manifold.

Ventilators may also be equipped with monitoring and alarm systems for patient-related parameters (e.g. pressure, volume, and flow) and ventilator function (e.g. air leakage, power failure, mechanical failure), backup batteries, oxygen tanks, and remote control. The pneumatic system is nowadays often replaced by a computer-controlled  turbo-pump.

Modern ventilators are electronically controlled by a small embedded system to allow exact adaptation of pressure and flow characteristics to an individual patient’s needs. Fine-tuned ventilator settings also serve to make ventilation more tolerable and comfortable for the patient. In Canada and the United States and in many parts of world, respiratory therapists are responsible for tuning these settings, while biomedical technologists are responsible for the maintenance.

The patient circuit usually consists of a set of three durable, yet lightweight plastic tubes, separated by function (e.g. inhaled air, patient pressure, exhaled air). Determined by the type of ventilation needed, the patient-end of the circuit may be either noninvasive or invasive.

Noninvasive methods, which are adequate for patients who require a ventilator only while sleeping and resting, mainly employ a nasal mask. Invasive methods require     intubation.  For long-term ventilator dependence will normally be a tracheostomy  cannula, as this is much more comfortable and practical for long-term care than is larynx or nasal intubation.

Life-critical system

Because failure may result in death, mechanical ventilation systems are classified as a life critical-system and precautions must be taken to ensure that they are highly reliable, including their  power supply .

Mechanical ventilators are therefore carefully designed so that no single point of failure can endanger the patient. They may have manual backup mechanisms to enable hand-driven respiration in the absence of power (such as the mechanical ventilator integrated into an  anesthetic machine . They may also have safety valves, which open to atmosphere in the absence of power to act as an anti-suffocation valve for spontaneous breathing of the patient. Some systems are also equipped with compressed-gas tanks, air compressors, and/or backup batteries to provide ventilation in case of power failure or defective gas supplies, and methods to operate or call for help if their mechanisms or software fail.

history of ventilator

source 

History of mechanical ventilator 


                

The history of mechanical ventilation begins with various versions of what was eventually called the iron lung, a form of noninvasive negative pressure ventilator widely used during the polio epidemics of the 20th century after the introduction of the “Drinker respirator” in 1928, improvements introduced by John Haven Emerson in 1931,  and the Both respirator in 1937. Other forms of noninvasive ventilators, also used widely for polio patients, include Biphasic Cuirass Ventilation, the rocking bed, and rather primitive positive pressure machines.

In 1949, John Haven Emerson developed a mechanical assister for anesthesia with the cooperation of the anesthesia department at Harvard University. Mechanical ventilators began to be used increasingly in anesthesia and intensive care during the 1950s. Their development was stimulated both by the need to treat polio patients and the increasing use of muscle relaxants during anesthesia. Relaxant drugs paralyze the patient and improve operating conditions for the surgeon but also paralyze the respiratory muscles.

In the United Kingdom, the East Radcliffe and Beaver models were early examples, the latter using an automotive wiper motor to drive the bellows used to inflate the lungs. Electric motors were, however, a problem in the operating theaters of that time, as their use caused an explosion hazard in the presence of flammable anesthetics such as ether and  cyclopropane .

In 1952, Roger Manley of the Westminster Hospital, London, developed a ventilator which was entirely gas driven, and became the most popular model used in Europe. It was an elegant design, and became a great favorite with European anesthetists for four decades, prior to the introduction of models controlled by electronics. It was independent of electrical power, and caused no explosion hazard. The original Mark I unit was developed to become the Manley Mark II in collaboration with the Blease company, who manufactured many thousands of these units. Its principle of operation was very simple, an incoming gas flow was used to lift a weighted bellows unit, which fell intermittently under gravity, forcing breathing gases into the patient’s lungs. The inflation pressure could be varied by sliding the movable weight on top of the bellows. The volume of gas delivered was adjustable using a curved slider, which restricted bellows excursion. Residual pressure after the completion of expiration was also configurable, using a small weighted arm visible to the lower right of the front panel. This was a robust unit and its availability encouraged the introduction of positive pressure ventilation techniques into mainstream European anesthetic practice.

The 1955 release of Forrest Bird’s “Bird Universal Medical Respirator” in the United States changed the way mechanical ventilation was performed, with the small green box becoming a familiar piece of medical equipment.  The unit was sold as the Bird Mark 7 Respirator and informally called the “Bird”. It was a pneumatic device and therefore required no electrical power source to operate.

Intensive care environments around the world revolutionized in 1971 by the introduction of the first  Servo 900 ventilator Elema – Schonander . It was a small, silent and effective electronic ventilator, with the famous SERVO feedback system controlling what had been set and regulating delivery. For the first time, the machine could deliver the set volume in volume control ventilation.

Ventilators used under increased pressure (hyperbaric) require special precautions and few ventilators can operate under these conditions. In 1979, Sechrist Industries introduced their Model 500A ventilator which was specifically designed for use with hyperbaric chambers.

In 1991 the SERVO 300 ventilator series was introduced. The platform of the SERVO 300 series enabled treatment of all patient categories, from adult to neonate, with one single ventilator. The SERVO 300 series provided a completely new and unique gas delivery system, with rapid flow-triggering response.

In 1999 the LTV (Laptop Ventilator) Series was introduced into the market. The new ventilator was significantly smaller than the ventilators of that time weighing ~14 lbs and around the size of a laptop computer. This new design kept the same functionality of the in hospital ventilators, while now opening up a world of opportunity of mobility for the patients.

A modular concept, meaning that the hospital has one ventilator model throughout the ICU department instead of a fleet with different models and brands for the different user needs, was introduced with SERVO-i in 2001. With this modular concept the ICU departments could choose the modes and options, software and hardware needed for a particular patient category.

mechanical ventilator

Cure for AIDS may be possible in near future


“London patient” becomes second person to be cured of AIDS after stem cell therapy. It has helped them put their infection under remission without medication. The breakthrough offers hope for a potential cure using gene manipulation for an infection. Concept that scientists will one day be able to end AIDS, the doctors said, but does not mean a cure for HIV has been found.

An HIV-positive man in Britain has become the second known adult worldwide to be cleared of the AIDS virus after he received a bone marrow transplant from an HIV resistant donor, his doctors said.

Almost three years after receiving bone marrow stem cells from a donor with a rare genetic mutation that resists HIV infection – and more than 18 months after coming off antiretroviral drugs – highly sensitive tests still show no trace of the man’s previous  HIV infection.

“There is no virus there that we can measure. We can’t detect anything,” said Ravindra Gupta, a professor and HIV biologist who co-led a team of doctors treating the man.

The case is a proof of the concept that scientists will one day be able to end AIDS, the doctors said, but does not mean a cure for HIV has been found.

Gupta described his patient as “functionally cured” and “in remission”, but cautioned: “It’s too early to say he’s cured.”

The man is being called “the London patient”, in part because his case is similar to the first known case of a functional cure of HIV – in an American man, Timothy Brown, who became known as the “ Berlin patient” when he underwent similar treatment in Germany in 2007 which also cleared his HIV.

 

Brown, who had been living in Berlin, has since moved to the United States and, according to HIV experts, is still HIV-free.

Some 37 million people worldwide are currently infected with  HIV  has killed around 35 million people worldwide since it began in the 1980s. Scientific research into the complex virus has in recent years led to the development of drug combinations that can keep it at bay in most patients.

Gupta, now at Cambridge University, treated the London patient when he was working at University College London. The man had contracted HIV in 2003, Gupta said, and in 2012 was also diagnosed with a type of blood cancer called Hodgkin’s Lymphoma.

In 2016, when he was very sick with cancer, doctors decided to seek a transplant match for him. “This was really his last chance of survival,” Gupta told Reuters in an interview.

The donor – who was unrelated – had a genetic mutation known as ‘CCR5 delta 32’, which confers resistance to HIV.

The transplant went relatively smoothly, but there were some side effects, including the patient suffering a period of “graft-versus-host” disease.

Most experts say it is inconceivable such treatments could be a way of curing all patients. The procedure is expensive, complex and risky. To do this in others, exact match donors would have to be found in the tiny proportion of people — most of them of northern European descent — who have the CCR5 mutation that makes them resistant to the virus.

Specialists said it is also not yet clear whether the CCR5 resistance is the only key – or whether the graft versus host disease may have been just as important. Both the Berlin and London patients had this complication, which may have played a role in the loss of HIV-infected cells.

Sharon Lewin, an expert at Australia’s Doherty Institute and co-chair of the International AIDS Society’s cure research advisory board, told Reuters the London case points to new avenues for study. “We haven’t cured HIV, but (this) gives us hope that it’s going to be feasible one day to eliminate the virus,” she said.

Gene manipulation, like any experimental technology, comes with several caveats, including concerns about the “off target effects” that can cause adverse mutations, including cancer.

 

Blog at WordPress.com.

Up ↑

%d bloggers like this: