Bosch & Speidel Oscillotonometer

WLMD ID: akgd
Before the advent of automatic blood pressure devices, the oscillotonometer allowed the anesthesiologist to read the patient's blood pressure even when access to the arm was blocked. Another advantage was that it could be operated with one hand. This freed the doctor's other hand to maintain the patient's airway or perform other important tasks. The cuff was applied to the patient before surgery began. Tubing between the cuff and the oscillotonometer allowed the apparatus to sit near the anesthesiologist. The oscillotonometer, popularized by German physiologist Heinrich von Recklinghausen (1867-1942), measures pressure using an aneroid manometer. This type of manometer employs a diaphragm sealed to one wall of a vacuum container to detect pressure changes. It also employs two rubber bladders in a single cuff. One bladder functions to amplify the pulse so that pressure fluctuations readily transfer to visible needle movements (or oscillations) on the pressure gauge. The other bladder is filled with air until the cuff is tight enough to occlude the main artery in the arm. The anesthesiologist used a valve and control lever just below the pressure gauge to control the release of pressure and visually read the blood pressure based on needle movements on the gauge. This example was made by Bosch & Speidel in Germany between 1945 and 1965. It was owned by Dr. John William Pender.

Catalog Record: Bosch & Speidel Oscillotonometer

Access Key: akgd
Accession No.: 1994-11-10-1 A

Title: Oscillotonometer “Scala Alternans” Altera / n. Dr. von Recklinghausen.
Author: Von Recklinghausen, Heinrich, 1867-1942.

Title variation: Alt Title
Title: Von Recklinghausen oscillotonometer.

Title variation: Alt Title
Title: Bocsh & Speidel oscillotonometer.

Title variation: Alt Title
Title: B & S oscillotonometer.

Publisher: [Jungingen, Germany] : [Bosch & Speidel], [1945-1965].

Physical Descript: 1 oscillotonometer : metals, glass ; 13 x 11 x 9 cm.

Subject: Blood Pressure Determination – instrumentation.
Subject: Blood Pressure Monitors.
Subject: Oscillometry – instrumentation.

Note Type: General
Notes: The end year of 1965 for the possible year of manufacture is based on the
year that Bosch & Speidel separated into Speidel & Keller and Bosch & Sons.

Note Type: With
Notes: The oscillotonometer is accompanied by red and black rubber tubing, a metal
pressure release valve, two metal tubing connectors red rubber inflating
built, a fabric cuff which contains two rubber bladders and is lined with
Velcro; The cuff measures approximately 54 cm. in length and 13 cm wide;
“PENDER” is written in black ink on one end of the cuff; The compression
bladder help in the cuff measures only 6 cm in width; All of these are stored
in an accompanying brown leather case that measures approximately 16.5 x 21 x
8.5 cm. (height, width, depth). There are no manufacturer’s markings on the
cuff, tubing or storage case.

Note Type: Citation
Notes: Ball C, Westhorpe RN. Blood pressure monitoring–the von Recklinghausen
oscillotonometer. Anaesth Intensive Care. 2009;37(2):161.

Note Type: Citation
Notes: Corall IM, Strunin L. Assessment of the Von Recklinghausen oscillotonometer.
Anaesthesia. 1975;30(1):59-66.

Note Type: Citation
Notes: Hutton P, Prys-Roberts C. The oscillotonometer in theory and practice. Br J
Anaesth. 1982;54(6):581-591.

Note Type: Citation
Notes: Volger-Ludwig K. Medical Technologies: Case Studies Bayern and
Baden-Württembert, Preliminary Draft. München, Germany: Economix Research &
Consulting; 2004:16.

Note Type: Citation
Notes: Magee PT. Physiological monitoring: principles and non-invasive monitoring.
In:Davey AJ, Diba A, eds. Ward’s Anaesthetic Equipment. 5th ed. Philadelphia:
Elsevier/Saunders; 2005:248-249.

Note Type: Physical Description
Notes: 1 oscillotonometer in nickel or stainless steel housing; The pressure gauge,
or dial, is circular and the face is marked in increments of five mm of
mercury from 0 on the lower left (approximately 7:30 if the gauge were a
clock) to 300 on the lower right (or approximately 4:30); The increments are
numbered in increments of 20; “mm Hg” is marked near the increment 0 and “mm
Hg = Torr” is marked hear the increment 300; The needle is thin and black and
rests at zero when not in use; Markings on the face of the gauge, starting at
the center top include, “Oscillotonometer [new line] n. Dr. von
Recklinghausen [new line] „SCALA ALTERNANS“ [new line] ALTERA”; Marked on the
bottom center of the face of the gauge is the Bosch & Speidel logo, which
includes the letter “B” to the left of a chalice and snake and the letter “S”
to the right; Just below the gauge is a metal pressure release valve and to
the left of this valve is a control lever; A round knob protrudes from the
upper left side of the gauge; A metal plate is attached to the back of the
gauge.

Note Type: Reproduction
Notes: Photographed by Mr. Steve Donisch on January 17, 2013.

Note Type: Acquisition
Notes: Donated to the WLM by John W. Pender, MD.

Note Type: Historical
Notes: Once surgery begins it is not uncommon for the anesthesiologist to have
limited access to much of the patient’s body, including the arms. Today with
the use of automatic blood pressure machines this is no longer a significant
obstacle. Before the advent of automatic devices, the oscillotonometer
allowed the anesthesiologist to read the patient’s blood pressure even when
access to the arm was blocked. Another advantage was that it could be
operated with one hand. This freed the doctor’s other hand to maintain the
patient’s airway or perform other important tasks. The cuff was applied to
the patient before surgery began. Tubing between the cuff and the
oscillotonometer allowed the apparatus to sit near the anesthesiologist.

Note Type: Historical
Notes: The oscillotonometer, popularized by German physiologist Heinrich von
Recklinghausen (1867-1942), measures pressure using an aneroid manometer.
This type of manometer employs a diaphragm sealed to one wall of a vacuum
container to detect pressure changes. It also employs two rubber bladders in
a single cuff. One bladder functions to amplify the pulse so that pressure
fluctuations readily transfer to visible needle movements (or oscillations)
on the pressure gauge. The other bladder is filled with air until the cuff is
tight enough to occlude the main artery in the arm. The anesthesiologist used
a valve and control lever just below the pressure gauge to control the
release of pressure and visually read the blood pressure based on needle
movements on the gauge. This example was made by Bosch & Speidel in Germany
between 1945 and 1965.

Note Type: Exhibition
Notes: Chosen for the WLM website (noted February 26, 2013).