“The brainstem serves as a conduit from the brain to the cranial nerves and spinal cord. As a result, the brainstem is involved with motor, sensory, and special sensory function, as well as regulation of temperature, cardiac function, respiratory function, and consciousness”.
Michael T. Milano, … Louis S. Constine, Organ Function and Clinical Significance; Late Effects after Radiation in Clinical Radiation Oncology (Fourth Edition), 2016. https://www.sciencedirect.com/topics/neuroscience/brainstem#:~:text=The%20brainstem%20serves%20as%20a,%2C%20respiratory%20function%2C%20and%20consciousness. ]
And this is what is so fascinating and disturbing about mental illness in general, but in the discussion of Bipolar illness in particular. As I have discussed in earlier posts, Dr Emile Kraepelin [with the help of his students] found changes to the “regulation of temperature, cardiac function, respiratory function, and consciousness” in the different ranges of physical signs and symptoms that he found in thousands of untreated bipolar illness patients during his long career. Dr Kraepelin discovered patterns of changes to the baseline resting heart rates, heart regularity, blood pressure, body temperature and respiratory rate. This suggests that the brainstem is responding to something, but what is it responding to? Di Kraepelin, upon finding abnormal rates of respiration in all states of bipolar illness, hypothesized that the patient’s body was trying to deal with metabolic dysfunction disturbing acid base balance. Today we might point out respiratory acid base imbalance as being especially problematic due to the abnormal breathing patterns. And respiratory acid base imbalance suggests too much or too little endogenous carbon dioxide, since carbon dioxide is continuously produced by metabolism and the respiratory rate will determine whether the proper quantity is left in the blood stream.
These changes seen in bipolar depression versus bipolar mania are like toxidromes, at least this is what it comes across as to me.
Hypercapnia [too much PaCO2] or hypocapnia {too little PaCO2] is toxic and will leave a clinical fingerprint to be detected by discerning doctors.
A toxic syndrome or toxidrome is a ‘clinical fingerprint’, characterised by a classic constellation of symptoms and signs due to toxic effects of chemicals in the body. It is a signature of a variety of poisoning [s].
Clinical Practice Guidelines : Toxidromes poisoning. https://www.rch.org.au/clinicalguide/guideline_index/Toxidromes_poisoning/
In attacks of depressive insanity, BP is very high, HR is also high-with arythmias, body temperature of low-with pale, cold even blue extremities and RR is too slow [slower than eupnea] , maybe too fast [faster. than eupnea], and can even be irregular [Cheynes-Stokes pattern]. Mania produces a different toxicodroome. [which Kraepelin discribes].
Eupnea is “normal breathing at rest”;….. An average breathing pattern is 12 breaths per minute and 500 mL per breath. There are types of altered breathing patterns that are symptoms of many diseases. Abnormal breathing patterns are important in clinical diagnosis of altered mental and mood and motor status in my opinion.
21.5D: Breathing Patterns – Medicine LibreTexts. Jan 17, 2023 https://med.libretexts.org/Bookshelves/Anatomy_and_Physiology/Anatomy_and_Physiology_(Boundless)/21%3A_Respiratory_System/21.5%3A_Mechanics_of_Breathing/21.5D%3A_Breathing_Patterns
So breathing is abnormal in bipolar attacks. Why do I consider this to be even more important than the other changes to the vital signs [which are very important, make no mistake about it] ?
Breathing rate is organized by the brain stem along with the help of chemical sensors [central and peripheral] and the ventilatory pump [all of which, I think are skeletal muscles].
If the breathing rate AND the mental/motor status are abnormal, then this may be the reason for the changes in the other systems and vital signs of the body, as they try to help manage the pH, PaCO2/PaO2 balance in the blood and other tissues [ie the brain] in order to keep the patient alive, even if it not possible to keep the patient mentally stable.
Ventilation is primarily controlled by the medulla [in the brainstem] , in response to pH changes sensed by the carotid bodies.. An acidotic cerebrospinal fluid pH triggers neuronal output and stimulates peripheral receptors in the lungs and respiratory muscles to augment ventilation. This system is dysfunctional in ventilatory failure, a diagnosis made on the basis of ABG analysis. ……. The signs and symptoms of detrimental breathing include dyspnea, tachypnea, tachycardia, hypertension, intercostal retraction, use of accessory muscles of ventilation, diaphoresis, and mental status changes. A patient with these signs and symptoms who has a normal Paco2 has impending ventilatory failure, a clinical diagnosis. Arterial Blood Gas Measurements, Robin Gross, William Peruzzi, in Critical Care Medicine (Third Edition), 2008 in https://www.sciencedirect.com/topics/nursing-and-health-professions/cerebrospinal-fluid-ph………..
Kraepelin found tachypnea, tachycardia, hypertension, mental status changes and bradypnea [a much rarer physical sign than tachypnea] and motor status changes [psychomotor retardation and excitement].
This suggests possible ventilatory failure due to a dysfunctional ventilatory system as the reason for the range of signs and symptoms in bipolar attacks.
And this is exactly what Kraepelin suspected; in his memoirs [or somewhere else in his copious writings], Kraepelin suggested that patients suffering from manic depressive insanity had ventilatory defects of injury, making respiratory metabolic balance harder to manage, especially when due to chronic exposure, pollution, respiratory illness and recovery, viruses, etc..breathing was made even harder than during periods of health. In periods of physical illness, the broken ventilatory system became overwhelmed and supportive medical care could be useful in restoring the broken system to its baseline state [which is sufficient somehow for normal mental and motor status and restoration of normal vital signs [with the most likely exception of eupnea].
I would like to add the possible hypothesis that eupnea is permanently lost to these patients due to neurological injury affecting the “control of breathing”.
This is why Paula’s case is important. We checked her breathing rate at rest because of kraepelin’s work. We never would have thought of it otherwise. Paula’s breathing looks completely normal and she feels it to be normal. Yet careful counting her breathing for a full minute with a stopwatch shows her to be breathing at a rate of 3 breaths per minute. How can that be? And why do we not notice? And why does Paula not notice?
to be continued………
Of Sound Mind 