To the Editor In January 2010, we implemented a system similar to that described by Epstein et al.1 to send Short Message Service (SMS) messages to staff of our cardiac surgical team to respond to emergency cases. In addition to sending SMS messages to cell phones, our system was also able to send text messages to hospital provided pagers. (Pager provider: Indiana Paging Network, messages sent to <10 digit pager number @ipnpaging.com>). Staff had the option of receiving a SMS message on either their cell phone or their pager. We also had staff reprogram their phones with a loud ring tone instead of the default chirp when a SMS message arrived. Systems such as that described by Epstein et al. and ours have multiple potential points of failure. The SMS message has to go through an e-mail server, through the cell phone carrier's gateway, and then though the cell tower nearest the cell phone subscriber.2 Should a natural disaster occur, for example, an earthquake, it is more than likely that one of these points would fail, causing a failure of the entire process. It is possible to build redundancy into the system by using more than one e-mail server or more than one SMS gateway. However, the final pathway for the SMS message is still the cell tower nearest the subscriber. Therefore, a method using as few failure points as possible is recommended. This would include an Internet-based option such as Voice over Internet Protocol (VoIP) phones, for example, Skype (Skype provides free computer to computer calls; www.skype.com); use of e-mail with both the sender and receiver using the same e-mail server to limit the number of transfers that the transmission has to make; and use of instant messaging (IM). Most new smart phones have Wi-Fi, and even if the cellular network is inoperable, these phones will still be able to send and receive VoIP-based phone calls, e-mail, and IM, provided they have Internet access.3 These systems are less likely to fail during natural disasters because of the in-built redundancy in the Internet network.4 Rather than concatenating the phone number with a code for the carrier (555-123-4567-V*), as is recommended by Epstein et al., and then having to parse this to determine the carrier, an alternate database design methodology5 would create a new field to store the carrier information. Using nonhospital e-mail systems to send recall messages is limited by restrictions placed by the e-mail provider. The e-mail provider that our application uses, Godaddy.com (http://www.godaddy.com) places a limit of 100 total addresses per e-mail message.6 For departments without the technical skills or manpower to develop a fully integrated response system, Google Voice (www.google.com/voice) provides a free phone number with the ability to send SMS messages to cell phones without having to know the cell phone carrier. However, there is a limit of 5 recipients at a time. It also allows the receipt of SMS replies and the ability to forward replies to an e-mail address. Adejare Windokun, MD Department of Anesthesiology Clarian Arnett Hospital Lafayette, Indiana Zumran Hamid, MD Department of Anesthesiology Methodist Hospital Merrillville, Indiana [email protected]