Suction Machines Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Clinical Use Blood from the surgical field Removing ingested toxins (stomach pump) Unwanted fats (liposuction) Mucosal secretions from the esophagus

Clinical Use In the developed world one normally uses the wall vacuum system instead of suction pumps

History The existence of a vacuum force was first discovered by Otto von Guericke in 1650 in an experiment where air molecules were removed from a sealed container. Once removed, the container's space became a vacuum. Not long after this discovery, the vacuum pump was invented to help chemists better understand the properties of gases. An empty container allowed chemists to refill it with different gases and study them in their pure forms, without the interference of air gases. Since then, vacuum technology has developed to the point where the full effects of this force can be utilized within a variety of applications. Today, there are three main types of vacuum pumps--compressed air pumps, electromechanical pumps and entrapment pumps. Compressed air pumps work to increase the pressure of a gas by decreasing the space that it occupies. They do this by forcing gas molecules through a small space, like a nozzle. When compressed gas is introduced into a high pressure environment, it creates a vacuum effect. Electromechanical pumps trap air inside moving mechanical parts--like rotors--then force it through a pump device. This process creates a vacuum effect. These are motorized devices that require electricity to run. Entrapment pumps are designed to catch gases and confine them in a sealed space, or chamber. All three methods have been adapted for use in various applications. http://www.history-science-technology.com/notes/notes%202.htm The piston pump of Ctesibius (an engineer from Alexandria, Egypt, 3rd century BC) was described by Philo of Byzantium (2nd century BC) because Ctesibius’ book was lost. It was a force pump and was submerged in water; (Fig. 1)[1].

Principles of Operation Pressure units: millimeters of mercury (mm Hg) pascals (Pa or kPa) inches or centimeters of water (inH2O or cmH2O) pounds per square inch (psi) Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA 1 mmHg = 0.133 kPa = 1.36 cmH2O = 0.535 inH2O = 0.193 psi

Principles of Operation Elements Source of suction (Mechanic or thermal pump) Tubing Collection bottle Canister or bottle Manometer Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA

Principles of Operation Mechanical Suction Source (hollow input tube) Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Principles of Operation Mechanic Source of suction (diaphragm type) Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Principles of Operation Electric pump induction motor Stator with windings Squirrel Cage rotor Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA Mirsad Todorovac (2006), 3 phase synchronous electric motor [graphic]. Retrieved from https://commons.wikimedia.org/wiki/File:Sink-320x240-3x-rot.gif

Principles of Operation Electric pump induction motor Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA S.J. de Waard (2011) Opengewerkte elektromotor [photograph]. Retrieved from https://commons.wikimedia.org/wiki/File:Rotterdam_Ahoy_Europort_2011_(14).JPG

Types of Pumps Rotary Vane Piston

Principles of Operation Mechanical Sources of Suction - Electric motor driven - Hand/Foot Pumps - Venturi with compressed air - Vane type  - Diaphragm type - Screw type - Piston type - Typically 20-30inHg maximum - Typically 20-30Lpm air flow Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA

Thermal/Thermotic Pumps Pedal pump Thermal Source of suction coil in the unit heats up for approximately 20-45 seconds cooling creates a suction airflow and pulls fluid from the wound site Typically 90-120 mmHg suction maximum.  Typically 1-2Lpm air flow

Principles of Operation Collection bottle (hollow input tube) Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Principles of Operation Collection bottle Float valve should be in the last canister before the connection Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA

Principles of Operation Fluid trap Energy Discharge: 0 to 360 watt/ seconds (Joules)… around 50 mA Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Operation Position the unit close to patient Plug into AC power (do not use extension cords) Attach first suction tubing from pump suction control to collection bottle outlet Attach second suction tubing to collection bottle inlet Ensure a rising float will block fluid flow to the pump Check all components and connections for tight fit Turn suction pump on (on/off electrical switch) Crimp tubing coming from the collection bottle inlet Adjust suction to desired level while observing vacuum gauge Initiate suction procedure

Circuit Malkin, Robert. Medical Instrumentation in the Developing World. Engineering World Health, 2006

Physical Methods of Microbial Control

Vertical Autoclave Snelling, Guy. “Autoclave Validation-What is Really Required?.” Retrieved from: http://www.frankshospitalworkshop.com/equipment/documents/ autoclaves/background/Autoclave_validation_-_what_is_really_required.pdf

Commercial Examples Massimiliano Mariani, (2009), A portable suction unit from an ambulance [photograph}. Retrieved from https://commons.wikimedia.org/wiki/File:Aspiratore.jpg R-E-A-L (2003), Suction device for use in dentistry [photoraph]. Retrieved from https://commons.wikimedia.org/wiki/File:2003-12-03-Saugmaschine.JPG

Commercial Examples Beukbeuk (2008), Medela breast pump [photograph]. Retrieved from https://commons.wikimedia.org/wiki/File:Medela_lactaline_select_breast_pump.jpg

Safety One should have at least 3 pressure intensity levels: Low (wound suction) Medium (chest tubes) High (airway and gastric suctioning) The staff member using the suction unit should always wear protective gloves. The reason this is important is because it's the user's thumb that occludes a hole on the catheter and the secretions must pass directly under that hole. The chances of coming in contact with those microorganisms are very high if gloves are not worn. They should also wash their hands immediately after suctioning and removal of the protective gloves. If the person using the suction machine is at risk of being splashed by secretions then eye and/or face protection should be worn.

Common Problems Clogs Leaks Collection Bottles Electrical Motor Pump valve contamination/corrosion or wear

Common Problems Clogs Tubes Filters 3 micron size or barb-hose barb PTFE  Lilly_M (2011) 0,22 ul PTFE filter [photograph]. Retrieved from https://commons.wikimedia.org/wiki/File:0,22_ul_PTFE_filter-01.jpg

Common Problems Leaks Apply Water and soap Public Domain Pictures, George Hodan (2012), Spray Bottle Spraying [photograph]. Retrieved from http://www.publicdomainpictures.net/view-image.php?image=67164&picture=spray-bottle-while-spraying

Common Problems Tube leak Jar/lid leak (bad o-ring, possibly) Tube blockage or kink Bad motor Bad power supply No collection bottle Float valve closes air pathway w/ full collection jar No filter Insufficient suction due to pump wear or corrosion.

Common Problems Electrical Pump Vibration between the suction machine and the floor Clogged bacterial filter Insufficient pressure/suction Ventilation grill obstructed Suction control knob is set to a low setting Vanes need replacing (in rotary vane style pump). -Vanes are numbered and need to be replaced in order Diaphragm needs cleaning or replacing Brushes need cleaning Motor needs lubrication

Preventive Maintenance PM (daily) Clean filters Clean air vents Ensure electrical plug and cord are in good condition Sterilize jars, tubing, other components that come into contact w/ patient fluids between each use in solution of water, detergent, and disinfectant Change bacteria filter if wet or discolored Check collection bottle/jar for cracks, chips, and other damage Make sure there is a sufficient supply of bacterial filters Check that float valve moves freely Ensure anti-static tubing is used   PM (1-3 months) Clean or replace air intake filter Clean brushes on motors as necessary Inspect power cord and plug Ensure vacuum works over full range of suction pressures if there is a control/knob Verify that overflow valve (float valve) works properly when container is filled with water Grounding resistance between chassis and ground pin should not exceed 0.5 ohms

Preventive Maintenance Bearings cleaning Hot light oil at 180-200° F may be flushed through the housing while the shaft is slowly rotated Light transformer oils, spindle oils or automotive flushing oils are suitable Oils heavier than light motor oils, such as SAE 10, are not as effective Automotive engine oils are not to be used. The detergents will leave deposits and restrict motor rotation

Preventive Maintenance Calibration: Not possible in most models

Preventive Maintenance One can check the pressure gauges value Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006), Pressure (mmHg) = Height of Water (in inches) ∗ 25.4 (mm/in) 13.6 (mmH20/mmHg

Suction Machine Troubleshooting Robert Malkin, Engineering World Health, “Suction Machine: Use and Operation” (2006),

Summary Quiz Clinical Use History Specifications Principles of Operation Block Diagram Commercial Examples Preventive Maintenance Common Problems Test Procedures

Quiz – Suction Machine What are the techniques to create vacuum?

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