Textbook of Maritime Medicine

9.6.1   Education for physicians providing medical advice

According to the IMO/ILO solution 164 the TMAS centre should provide medical advice for seafarers 24 h/day, 365 days/year. TMAS should be permanently staffed by physicians qualified in conducting remote consultations and who are well versed in the particular nature of treatment onboard ship.

Maritime healthcare deals with a constant increase in medical knowledge. Giving medical advice to seafarers means to handle a wide range of different diseases in a remote situation.

In this context it is quite important to be able to diagnose a disease without an extensive examination. The responsible physician should be also aware of the wide range of diseases and risks at work of a seafarer population (males of 20-55 years of age). Epidemiological knowledge in Maritime Medicine is as important as practical experience onboard ships in order to assist, advise and treat seafarers evidence based and in the best possible way.

The advising doctors need to have a broad based medical knowledge and experience in order to be able to give advice on best medical treatment. The advising physicians should also have practical experience in maritime emergency medicine (e.g. helicopter evacuations at sea, working knowledge on rescue vessels or with repatriation of seafarers) in order to be able to provide best and instant advice in an emergency situation at sea. The TMAS physicians need therefore continuously to be up to date in rescue techniques at sea.

The physicians working at the TMAS centres usually are specialists in the following areas:

Emergency medicine and anaesthesiology and intensive care, internal medicine (including following sub-specialities: cardiology, gastroenterology, pulmonology, infectious diseases, tropical and travel medicine), surgery (general surgery, orthopaedic surgery, vascular surgery, thoracic surgery and neurosurgery), neurology, pain medicine, radiology, urology, gynaecology and obstetrics, ears-nose and throat diseases, ophthalmology and dermatology. It may be necessary to access further advice from paediatrics and dental surgeons.

Usually the TMAS physician has the role of a GP and must give advice accordingly. Most of the medical cases onboard are not life threatening and are relatively simple to treat. Even today the term “keep it simple and safe” has not lost its significance for medical advice and treatment on board. The success of a best practice treatment is depending on the information given by the responsible ship’s officer onboard. Especially in a remote situation a good communication (onshore/onboard), is fundamental for an effective medical treatment of patients at sea. This fact is even more important if we take in consideration that there is an increased use of interactive audiovisual communication between medical professionals onshore and first aid provider onboard ships.

Physicians onshore, dealing with new communication technologies onboard (e.g. telemedicine equipment, V-SAT video conferences etc.), should have an up to date education in the use of new telecommunication systems  at sea that enables them to use these new technologies and/or media in an efficient way in order to provide best practice medical treatment of seafarers. Furthermore an international standardisation of maritime telemedicine technology onboard ships would be essential in order to communicate more effectively while giving medical advice to seafarers.

9.6.2   Services around the world

The medical support services via radio of all countries are listed in Part D  of “The List of Radiodetermination  and special Service Stations (List VI)  published by the Radiocommunication Sector of the ITU and available at its website at www.itu.int/ITU-R.  This publication is found on almost every vessel. If it is not on board, the ship may call the closest coast radio station and inquire about the availability of  medical support services. The particulars of coast radio stations as well as earth stations are listed in “List of Coast Stations (List 4)” which can be found at the web address as indicated above.

9.6.3   Satellite Systems

A satellite connection can be described as an arrangement with outgoing and incoming data from a computer, via satellite, to another computer. The subscriber needs a satellite dish antenna and a transceiver that operates in the microwave portion of the radio spectrum.

The different types of satellite systems available for use on board ships are:

• Inmarsat Fleet 33, 55, 77
• Inmarsat Fleet Broadband 250 and 500
• Iridium Open Port
• Very Small Aperture Terminal (V-SAT), KU-band and C-band

INMARSAT Fleet 33, 55 & 77 satellite systems

INMARSAT operates a global satellite network, and offers mobile satellite communication services, not only in the maritime marked, but also for land and aeronautical service.

The coverage for the INMARSAT Fleet Systems is arranged by four satellites that move in geosynchronous orbit and cover the area between 75 degrees north and 75 degrees south.

In use on board ships this system is depending on the Global- or Spot-Beam cover. A global beam cover is a satellite signal that covers most of the global area. As you can see in the figure some parts of the world are not covered. This is the northern middle east on the coast of Russia and the Northern Coast of Greenland and Canada.“ A spot beam, in telecommunications parlance, is a satellite signal that is especially concentrated in power (i.e. sent by a high-gain antenna) so that it will cover only a limited geographical  area. Spot beams are used so that only earth stations in a particular intended reception area can properly receive the satellite signal. One notable example of the use of spot beams is on direct broadcast satellite systems such as DirecTV and Dish Network that deliver local broadcast television via satellite only to viewers in the part of North America from which those terrestrial broadcast stations originate. Spot beams allow satellites to transmit different data signals using the same frequency. Because satellites have a limited number of frequencies to use, the ability to re-use a frequency for different geographical locations (without different data interfering with each other at the receiver) allows for more simplified receiver designs.

The Global Beam Fleet 33 and 55 systems and the Fleet 77 system are only voice based, and are the gateway to safe, secure and reliable communications on board the modern ship. The system provides voice, mobile ISDN (up to 64kbps) and Mobile Packet Data Service (MPDS) on the same terminal for all ocean regions.

MPDS  (Mobile Packet Data Service) (satellite-based service), 64kbps(kilo bits per second)

ISDN (Integrated Services Digital Network) and 3,1 Khz audio.

• Spot Beam Fleet 33 - fax, 9,6 kbps data, MPDS
• Spot Beam Fleet 55 – fax, ISDN, MPDS, 3,1 kHz audio    
• Spot Beam Fleet 77 -  128kbps ISDN

Figure 9.6.1: Footprints of the INMARSAT Spot- and Global Beam.Parts of the northern territory are not covered. The yellow parts are the INMARSAT Spot Beam.The footprints are the INMARSAT Global Beam . Source http://www.inmarsat.com/

INMARSAT Fleet Broadband 250 & 500 satellite systems

The Fleet Broadband Satellite System is the first maritime communication service which provides cost-effective broadband data and voice, simultaneously, through a compact antenna on a global basis. The coverage for the Fleet Broadband is supported by three satellites in geosynchronous orbit. The system covers an area between 75 degrees north and 75 degrees south.     

 Figure 9.6.2

 INMARSAT Fleet Broadband 250

antenna; http://www.inmarsat.com/

The INMARSAT Broadband System

This system has a standard IP up to 432 kbps over a shared channel, for e-mail, internet and intranet access. The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched internet work using the Internet Protocol Suite. The Internet Protocol Suite (commonly known as TCP/IP) is the set of communications protocols used for the Internet and other similar networks. It is named from two of the most important protocols in it: the Transmission Control Protocol (TCP) and the Internet Protocol (IP), which were the first two networking protocols defined in this standard. Today's IP networking represents a synthesis of several developments that began to evolve in the 1960s and 1970s, namely the Internet and LANs (Local Area Networks), which emerged in the mid- to late-1980s, together with the advent of the World Wide Web in the early 1990s. The Internet Protocol Suite, like many protocol suites, may be viewed as a set of layers. Each layer solves a set of problems involving the transmission of data, and provides a well-defined service to the upper layer protocols based on using services from some lower layers. Upper layers are logically closer to the user and deal with more abstract data, relying on lower layer protocols to translate data into forms that can eventually be physically transmitted. The Streaming IP – Streamed media are multimedia that are constantly received by, and normally presented to, an end-user while it is being delivered by a streaming provider and the guaranteed data rates on demand is up to 256 kbps.

The Voice – can make phone calls at the same time as accessing data-applications and the ISDN – can support ISDN at 284 kbps for legacy applications. (A legacy system is an old computer system or application program that continues to be used, typically because it still functions for the users' needs, even if a newer technology w usually ould be available. "Legacy" may have little to do with the size or age of the system). A SMS text – can usually be sent by the INMARSAT Fleet Broadband System.

Fleet Broadband (FB) 250 System: FB 250 offers a standard Internet Protocol (IP) up to 284 kbps and Streaming IP up to 128 kbps. The antenna is 25 cm in diameter. Fleet Broadband (FB) 500 System: FB 500 offers a standard Internet Protocol (IP) up to 432 kbps and Streaming IP up to 356 kbps. The antenna is 50 cm in diameter.

 Iridium Open Port Satellite System

Figure 9.6.3:  The open port satellite antenna.                       
 

Marine communications got a new system in 2008. Iridium introduced the Open Port. Worldwide Communication with such a small antenna (9 X 21 inches) and up to 128 Kbps transmission speed. The system is  viable from offshore vessels that are too small for a large dome. The maritime voice and data service, called Iridium Open Port, which is the world’s first global and high speed network satellite system and specifically engineered for the maritime marked. This system offers true IP connectivity with up to three phone lines available for simultaneous use. The system consistis of 66 pieces of low-earth  

 V-SAT Satellite Communication and Satellite Internet Terminals

V-SAT stands for Very Small Aperture Terminal – and is a sundry for every type of satellite product from small components of a system to complete systems. It has been used to describe both one-way and interactive systems. Both data and  voice systems are included. Generally, these systems operate in the Ku-band and C-band frequencies. As a rule of thumb the C band  (can withstand rain, but requires larger antennas) is used in Asia, Africa and Latin America whilst Ku-band (which can use smaller antennas, but suffers from rain fade in heavy rain) is used in Europe and North America. Typically, interactive Ku-band antenna sizes range from 75 centimetres to 1.8 metres and C-band from 1.8 metres to 2.4 metres. One way systems can use antennas as small as 45 centimetres.

Typical C Band antennas have a seize from 1,8 metres to 2,4 metres. The frequencies used 3 to 7 GHz. These systems are normally used for global coverage with the antenna pointing to one satellite.

9.6.4   Communication modes

Aksel Schreiner

Direct communication between shore and vessels became possible in the beginning of the 20^th century based on Marconi’s successful experiments with electromagnetic waves.In 1906 the “Radio Convention” was established in Berlin with the intention to regulate radio communication. Henceforward, radio communication with ships became commonplace.

The mode of communication was the morse code, the binary system with dots and dashes invented by Samuel Morse.  Despite the fact that the morse code is the most efficient of all radio modes in terms of penetration, its use faded out at the end of the 21^st century to make place for a more time efficient system, such as the telex.The telex communication was made possible by the invention of another binary, alphanumeric alphabet invented by Baudot and later developed to the ASCII code. Now, clear text could be transmitted automatically without the need for interpretation.  It represented the predecessor of the e-mail of today. The telex was introduced in the sixties and was widely used in administration, business and shipping. However, the advent of the internet in the eighties made the telex obsolete. It could not compete with  telefax, pc and modern printers,  and  telex networks  were closed down around 2000.

The telefax systems is still active (2009) but is probably also approaching its obsolescence because facsimiles of documents and pictures can easily be transmitted over the internet.

Today telephone communication is the dominating long distance mode for ships. In the early twenties the maritime telephone communication was restricted to coastal and other short distance traffic. It was not until after World War ll – around 1950 - that telephony on HF (short wave) with world wide coverage became available. But even this mode had a limited life span and has to a great part been replaced by satellite communication. The advent of satellite systems (see above) around 1980 provided high quality telephone and data communication with almost world wide coverage.

Frequencies

LF, MF and HF. The early spark radio emitters produced frequencies in LF and MF  (long and medium wave) that required enormous antennas. After 20 years the communication moved to HF (short wave) Telephony on HF and MFis to a certain extent still in use in some countries.

VHF (meter band) has only a limited direct reach and is mostly used for communication in coastal areas and for port services. The band is widely used by leisure boats. Most of the channels in this band are simplex channels i.e. only one person can talk at a time and the use of a microphone button is necessary. However, the maritime VHF offers different channels, such as port service channels, traffic channels and an international emergency channel (Ch 16) Via traffic channels the coast radio stations can setup world wide connections with duplex technique (microphone button not necessary)

UHF (cm band/mobile phone).Radio communication in the UHF segment is not commonly used in shipping. However, the GSM mobile phone system uses this segment. The mobile phone system is widely used by ships and fishing vessels in coastal areas. Some satellites are adapted to the GSM system and can transfer signals to and from mobile users in most parts of the world, even at sea.

Communication modes today

Telephone

Telephone communication via satellite is by far the most used mode for long distance communication in the shipping industry. The signals pass from the land based telephone net or mobile net via an earth station and a satellite to the recipient, and back. The audio is usually of high quality even if some delay or echo may occur.

Data communication. E-mail 

 Digital data communication via satellite opens for many possibilities. The hitherto most used mode is e-mail. The written message offers – and documents - exact and unequivocal information. However, e-mails can be intercepted and tempered with. Therefore, encrypting of the messages is mandatory to obey the duty of confidentiality.  Software that encrypts and decrypts e-mail messages is commercially available. Some software programmes not only take care of the encrypting, but also offer transfer of other information (see below), monitor the consultation, and offer filing systems.

Tranfer of still pictures

The use of still pictures in providing medical advice to ships came into use in the nineties. Most vessels now have a high quality digital camera.Still photos represented a major improvement of the diagnostic possibilities. A high resolution colour photography is specially helpful in the diagnosis of dermatological conditions, but also in other diseases and in many types of injuries. Pictures are commonly transferred as attachments to encrypted e-mail.

 Transfer of video in real time

 In land based medicine, the use of video consultations and video diagnostics has enjoyed great success. It would have been a great advantage if this technology was available also in the maritime setting.  So far, the data transmission speed of satellites and the cost of transmission limit the use of video consultations at sea. However, video consultations with a limited resolution and a fairly satisfactory frame rate are possible even today. It is no doubt that development within data compression technology and reduction in prices for transmission will in the near future make high quality video consultations possible also at sea.

Transfer of vital parameters

  Vital parameters such as oxygen saturation, pulse, blood pressure and ECG are essential in monitoring seriously ill patients. Easy-to-use devices for registration of such parameters are commercially available. Unlike video, the transmission of these data via satellite does not require a large band with.