Houston Cardiovascular Associates Houston Cardiovascular Associates

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Stages of Sleep

Overview

The sleep cycle is divided into two main stages: non-rapid eye movement (non-REM) and rapid eye movement (REM).

Non-REM sleep

Non–rapid eye movement sleep has three stages:

  • Stage N1 occurs right after you fall asleep and is very short (usually less than 10 minutes). It involves light sleep from which you can be awakened easily.
  • Stage N2 lasts from about 30 to 60 minutes. During this stage, your muscles become more relaxed and you may begin to have slow-wave (delta) brain activity.
  • Stage N3 is deep sleep and lasts about 20 to 40 minutes. During this stage, delta brain activity increases and you may have some body movements. It is very hard to wake up someone in stage N3.

REM sleep

Most dreaming happens during REM sleep. During REM sleep:

  • The eyes and eyelids flutter.
  • Breathing becomes irregular. During REM sleep, it is normal to have short episodes when breathing stops (apnea).
  • The brain paralyzes your muscles so you do not act out the dreams.

During sleep, a person usually progresses through the 3 stages of non-REM sleep before entering REM sleep. This takes about 1 to 2 hours after falling asleep. The sleep cycle is usually repeated about 4 to 6 times each night.

Related Information

Credits

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Dear patient

I am excited to announce that I will be relocating my practice to Houston Methodist DeBakey Cardiology Associates. Starting November 4, 2024, my new address will be:

Houston Methodist DeBakey Cardiology Associates
6550 Fannin St.
Smith Tower, Suite 1901
Houston, TX 77030

Please note that my phone number and fax number will also change to the following:
24-Hour Telephone: 713-441-1100
Fax: 713-790-2643
Clinical Support Telephone (M-F, 8-5): 713-441-3515

I am excited about caring for you in my new office and hope you will make the transition with me. I will also continue to refill your medications as I have in the past. To assist, please provide your pharmacy with my new contact information.

Please consider checking your prescription refills to verify that you have enough medication on hand to last you until your next visit. Please note that your medical records will remain at my former office until you authorize their transfer. If you choose for me to continue providing your medical care, please complete and sign the enclosed “Authorization for Release of Medical Records” form and fax it to 713-790-2643. Once we receive your authorization, we will be happy to process the request for you.

Thank you for entrusting me with your medical care. My new team and I are dedicated to making this transition as seamless as possible. For help scheduling an appointment and transitioning your care, please call my new office number above.

I look forward to continuing your care at my new location.

Sincerely,
Gopi A. Shah, MD

Dear patient

Dr. Albert Raizner, Dr. Michael Raizner, and Dr. Mohamed El-Beheary are excited to announce that our practice, Houston Cardiovascular Associates, will merge with Houston Cardiovascular Associates on November 1, 2024.

Our new offices are similarly located in Houston, near the Texas Medical Center and in Sugar Land. Our in-hospital care will continue at Houston Methodist Hospital in the Texas Medical Center and Houston Methodist Sugar Land Hospital. Importantly, our new offices expand our services with state-of-the-art equipment and amenities. Our core values will always be, as they began over 40 years ago when Dr. Albert Raizner founded HCA:

Integrity – Compassion – Accountability

Our new address and contact information are:

Your medical records are confidential and remain available at our new locations. We consider it a privilege to serve as your cardiologists and look forward to your continuing with us. However, should you desire to transfer to another physician, you may request a copy of your records by contacting us at our new addresses and phone numbers listed above.

We thank you for your trust and loyalty. As always, we will continue to be here to take care of you. Please do not hesitate to contact us if you have any questions or concerns.

Sincerely,

Dr. Albert Raizner,
Dr. Michael Raizner,
Dr. Mohamed El-Beheary